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Diffstat (limited to 'execute_cmd.c')
| -rw-r--r-- | execute_cmd.c | 5936 |
1 files changed, 5936 insertions, 0 deletions
diff --git a/execute_cmd.c b/execute_cmd.c new file mode 100644 index 0000000..8b3c83a --- /dev/null +++ b/execute_cmd.c @@ -0,0 +1,5936 @@ +/* execute_cmd.c -- Execute a COMMAND structure. */ + +/* Copyright (C) 1987-2018 Free Software Foundation, Inc. + + This file is part of GNU Bash, the Bourne Again SHell. + + Bash is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + Bash is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with Bash. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "config.h" + +#if !defined (__GNUC__) && !defined (HAVE_ALLOCA_H) && defined (_AIX) + #pragma alloca +#endif /* _AIX && RISC6000 && !__GNUC__ */ + +#include <stdio.h> +#include "chartypes.h" +#include "bashtypes.h" +#if !defined (_MINIX) && defined (HAVE_SYS_FILE_H) +# include <sys/file.h> +#endif +#include "filecntl.h" +#include "posixstat.h" +#include <signal.h> +#if defined (HAVE_SYS_PARAM_H) +# include <sys/param.h> +#endif + +#if defined (HAVE_UNISTD_H) +# include <unistd.h> +#endif + +#include "posixtime.h" + +#if defined (HAVE_SYS_RESOURCE_H) && !defined (RLIMTYPE) +# include <sys/resource.h> +#endif + +#if defined (HAVE_SYS_TIMES_H) && defined (HAVE_TIMES) +# include <sys/times.h> +#endif + +#include <errno.h> + +#if !defined (errno) +extern int errno; +#endif + +#define NEED_FPURGE_DECL +#define NEED_SH_SETLINEBUF_DECL + +#include "bashansi.h" +#include "bashintl.h" + +#include "memalloc.h" +#include "shell.h" +#include <y.tab.h> /* use <...> so we pick it up from the build directory */ +#include "parser.h" +#include "flags.h" +#include "builtins.h" +#include "hashlib.h" +#include "jobs.h" +#include "execute_cmd.h" +#include "findcmd.h" +#include "redir.h" +#include "trap.h" +#include "pathexp.h" +#include "hashcmd.h" + +#if defined (COND_COMMAND) +# include "test.h" +#endif + +#include "builtins/common.h" +#include "builtins/builtext.h" /* list of builtins */ + +#include "builtins/getopt.h" + +#include <glob/strmatch.h> +#include <tilde/tilde.h> + +#if defined (BUFFERED_INPUT) +# include "input.h" +#endif + +#if defined (ALIAS) +# include "alias.h" +#endif + +#if defined (HISTORY) +# include "bashhist.h" +#endif + +#if defined (HAVE_MBSTR_H) && defined (HAVE_MBSCHR) +# include <mbstr.h> /* mbschr */ +#endif + +extern int command_string_index; +extern char *the_printed_command; +extern time_t shell_start_time; +#if 0 +extern char *glob_argv_flags; +#endif + +extern int close __P((int)); + +/* Static functions defined and used in this file. */ +static void close_pipes __P((int, int)); +static void do_piping __P((int, int)); +static void bind_lastarg __P((char *)); +static int shell_control_structure __P((enum command_type)); +static void cleanup_redirects __P((REDIRECT *)); + +#if defined (JOB_CONTROL) +static int restore_signal_mask __P((sigset_t *)); +#endif + +static void async_redirect_stdin __P((void)); + +static int builtin_status __P((int)); + +static int execute_for_command __P((FOR_COM *)); +#if defined (SELECT_COMMAND) +static int displen __P((const char *)); +static int print_index_and_element __P((int, int, WORD_LIST *)); +static void indent __P((int, int)); +static void print_select_list __P((WORD_LIST *, int, int, int)); +static char *select_query __P((WORD_LIST *, int, char *, int)); +static int execute_select_command __P((SELECT_COM *)); +#endif +#if defined (DPAREN_ARITHMETIC) +static int execute_arith_command __P((ARITH_COM *)); +#endif +#if defined (COND_COMMAND) +static int execute_cond_node __P((COND_COM *)); +static int execute_cond_command __P((COND_COM *)); +#endif +#if defined (COMMAND_TIMING) +static int mkfmt __P((char *, int, int, time_t, int)); +static void print_formatted_time __P((FILE *, char *, + time_t, int, time_t, int, + time_t, int, int)); +static int time_command __P((COMMAND *, int, int, int, struct fd_bitmap *)); +#endif +#if defined (ARITH_FOR_COMMAND) +static intmax_t eval_arith_for_expr __P((WORD_LIST *, int *)); +static int execute_arith_for_command __P((ARITH_FOR_COM *)); +#endif +static int execute_case_command __P((CASE_COM *)); +static int execute_while_command __P((WHILE_COM *)); +static int execute_until_command __P((WHILE_COM *)); +static int execute_while_or_until __P((WHILE_COM *, int)); +static int execute_if_command __P((IF_COM *)); +static int execute_null_command __P((REDIRECT *, int, int, int)); +static void fix_assignment_words __P((WORD_LIST *)); +static int execute_simple_command __P((SIMPLE_COM *, int, int, int, struct fd_bitmap *)); +static int execute_builtin __P((sh_builtin_func_t *, WORD_LIST *, int, int)); +static int execute_function __P((SHELL_VAR *, WORD_LIST *, int, struct fd_bitmap *, int, int)); +static int execute_builtin_or_function __P((WORD_LIST *, sh_builtin_func_t *, + SHELL_VAR *, + REDIRECT *, struct fd_bitmap *, int)); +static void execute_subshell_builtin_or_function __P((WORD_LIST *, REDIRECT *, + sh_builtin_func_t *, + SHELL_VAR *, + int, int, int, + struct fd_bitmap *, + int)); +static int execute_disk_command __P((WORD_LIST *, REDIRECT *, char *, + int, int, int, struct fd_bitmap *, int)); + +static char *getinterp __P((char *, int, int *)); +static void initialize_subshell __P((void)); +static int execute_in_subshell __P((COMMAND *, int, int, int, struct fd_bitmap *)); +#if defined (COPROCESS_SUPPORT) +static void coproc_setstatus __P((struct coproc *, int)); +static int execute_coproc __P((COMMAND *, int, int, struct fd_bitmap *)); +#endif + +static int execute_pipeline __P((COMMAND *, int, int, int, struct fd_bitmap *)); + +static int execute_connection __P((COMMAND *, int, int, int, struct fd_bitmap *)); + +static int execute_intern_function __P((WORD_DESC *, FUNCTION_DEF *)); + +/* Set to 1 if fd 0 was the subject of redirection to a subshell. Global + so that reader_loop can set it to zero before executing a command. */ +int stdin_redir; + +/* The name of the command that is currently being executed. + `test' needs this, for example. */ +char *this_command_name; + +/* The printed representation of the currently-executing command (same as + the_printed_command), except when a trap is being executed. Useful for + a debugger to know where exactly the program is currently executing. */ +char *the_printed_command_except_trap; + +/* For catching RETURN in a function. */ +int return_catch_flag; +int return_catch_value; +procenv_t return_catch; + +/* The value returned by the last synchronous command. */ +volatile int last_command_exit_value; + +/* Whether or not the last command (corresponding to last_command_exit_value) + was terminated by a signal, and, if so, which one. */ +int last_command_exit_signal; + +/* Are we currently ignoring the -e option for the duration of a builtin's + execution? */ +int builtin_ignoring_errexit = 0; + +/* The list of redirections to perform which will undo the redirections + that I made in the shell. */ +REDIRECT *redirection_undo_list = (REDIRECT *)NULL; + +/* The list of redirections to perform which will undo the internal + redirections performed by the `exec' builtin. These are redirections + that must be undone even when exec discards redirection_undo_list. */ +REDIRECT *exec_redirection_undo_list = (REDIRECT *)NULL; + +/* When greater than zero, value is the `level' of builtins we are + currently executing (e.g. `eval echo a' would have it set to 2). */ +int executing_builtin = 0; + +/* Non-zero if we are executing a command list (a;b;c, etc.) */ +int executing_list = 0; + +/* Non-zero if failing commands in a command substitution should not exit the + shell even if -e is set. Used to pass the CMD_IGNORE_RETURN flag down to + commands run in command substitutions by parse_and_execute. */ +int comsub_ignore_return = 0; + +/* Non-zero if we have just forked and are currently running in a subshell + environment. */ +int subshell_environment; + +/* Count of nested subshells, like SHLVL. Available via $BASH_SUBSHELL */ +int subshell_level = 0; + +/* Currently-executing shell function. */ +SHELL_VAR *this_shell_function; + +/* If non-zero, matches in case and [[ ... ]] are case-insensitive */ +int match_ignore_case = 0; + +int executing_command_builtin = 0; + +struct stat SB; /* used for debugging */ + +static int special_builtin_failed; + +static COMMAND *currently_executing_command; + +/* The line number that the currently executing function starts on. */ +static int function_line_number; + +/* XXX - set to 1 if we're running the DEBUG trap and we want to show the line + number containing the function name. Used by executing_line_number to + report the correct line number. Kind of a hack. */ +static int showing_function_line; + +static int connection_count; + +/* $LINENO ($BASH_LINENO) for use by an ERR trap. Global so parse_and_execute + can save and restore it. */ +int line_number_for_err_trap; + +/* A sort of function nesting level counter */ +int funcnest = 0; +int funcnest_max = 0; + +int evalnest = 0; +int evalnest_max = EVALNEST_MAX; + +int sourcenest = 0; +int sourcenest_max = SOURCENEST_MAX; + +volatile int from_return_trap = 0; + +int lastpipe_opt = 0; + +struct fd_bitmap *current_fds_to_close = (struct fd_bitmap *)NULL; + +#define FD_BITMAP_DEFAULT_SIZE 32 + +/* Functions to allocate and deallocate the structures used to pass + information from the shell to its children about file descriptors + to close. */ +struct fd_bitmap * +new_fd_bitmap (size) + int size; +{ + struct fd_bitmap *ret; + + ret = (struct fd_bitmap *)xmalloc (sizeof (struct fd_bitmap)); + + ret->size = size; + + if (size) + { + ret->bitmap = (char *)xmalloc (size); + memset (ret->bitmap, '\0', size); + } + else + ret->bitmap = (char *)NULL; + return (ret); +} + +void +dispose_fd_bitmap (fdbp) + struct fd_bitmap *fdbp; +{ + FREE (fdbp->bitmap); + free (fdbp); +} + +void +close_fd_bitmap (fdbp) + struct fd_bitmap *fdbp; +{ + register int i; + + if (fdbp) + { + for (i = 0; i < fdbp->size; i++) + if (fdbp->bitmap[i]) + { + close (i); + fdbp->bitmap[i] = 0; + } + } +} + +/* Return the line number of the currently executing command. */ +int +executing_line_number () +{ + if (executing && showing_function_line == 0 && + (variable_context == 0 || interactive_shell == 0) && + currently_executing_command) + { +#if defined (COND_COMMAND) + if (currently_executing_command->type == cm_cond) + return currently_executing_command->value.Cond->line; +#endif +#if defined (DPAREN_ARITHMETIC) + if (currently_executing_command->type == cm_arith) + return currently_executing_command->value.Arith->line; +#endif +#if defined (ARITH_FOR_COMMAND) + if (currently_executing_command->type == cm_arith_for) + return currently_executing_command->value.ArithFor->line; +#endif + + return line_number; + } + else + return line_number; +} + +/* Execute the command passed in COMMAND. COMMAND is exactly what + read_command () places into GLOBAL_COMMAND. See "command.h" for the + details of the command structure. + + EXECUTION_SUCCESS or EXECUTION_FAILURE are the only possible + return values. Executing a command with nothing in it returns + EXECUTION_SUCCESS. */ +int +execute_command (command) + COMMAND *command; +{ + struct fd_bitmap *bitmap; + int result; + + current_fds_to_close = (struct fd_bitmap *)NULL; + bitmap = new_fd_bitmap (FD_BITMAP_DEFAULT_SIZE); + begin_unwind_frame ("execute-command"); + add_unwind_protect (dispose_fd_bitmap, (char *)bitmap); + + /* Just do the command, but not asynchronously. */ + result = execute_command_internal (command, 0, NO_PIPE, NO_PIPE, bitmap); + + dispose_fd_bitmap (bitmap); + discard_unwind_frame ("execute-command"); + +#if defined (PROCESS_SUBSTITUTION) + /* don't unlink fifos if we're in a shell function; wait until the function + returns. */ + if (variable_context == 0 && executing_list == 0) + unlink_fifo_list (); +#endif /* PROCESS_SUBSTITUTION */ + + QUIT; + return (result); +} + +/* Return 1 if TYPE is a shell control structure type. */ +static int +shell_control_structure (type) + enum command_type type; +{ + switch (type) + { +#if defined (ARITH_FOR_COMMAND) + case cm_arith_for: +#endif +#if defined (SELECT_COMMAND) + case cm_select: +#endif +#if defined (DPAREN_ARITHMETIC) + case cm_arith: +#endif +#if defined (COND_COMMAND) + case cm_cond: +#endif + case cm_case: + case cm_while: + case cm_until: + case cm_if: + case cm_for: + case cm_group: + case cm_function_def: + return (1); + + default: + return (0); + } +} + +/* A function to use to unwind_protect the redirection undo list + for loops. */ +static void +cleanup_redirects (list) + REDIRECT *list; +{ + do_redirections (list, RX_ACTIVE); + dispose_redirects (list); +} + +void +undo_partial_redirects () +{ + if (redirection_undo_list) + { + cleanup_redirects (redirection_undo_list); + redirection_undo_list = (REDIRECT *)NULL; + } +} + +#if 0 +/* Function to unwind_protect the redirections for functions and builtins. */ +static void +cleanup_func_redirects (list) + REDIRECT *list; +{ + do_redirections (list, RX_ACTIVE); +} +#endif + +void +dispose_exec_redirects () +{ + if (exec_redirection_undo_list) + { + dispose_redirects (exec_redirection_undo_list); + exec_redirection_undo_list = (REDIRECT *)NULL; + } +} + +void +dispose_partial_redirects () +{ + if (redirection_undo_list) + { + dispose_redirects (redirection_undo_list); + redirection_undo_list = (REDIRECT *)NULL; + } +} + +#if defined (JOB_CONTROL) +/* A function to restore the signal mask to its proper value when the shell + is interrupted or errors occur while creating a pipeline. */ +static int +restore_signal_mask (set) + sigset_t *set; +{ + return (sigprocmask (SIG_SETMASK, set, (sigset_t *)NULL)); +} +#endif /* JOB_CONTROL */ + +#ifdef DEBUG +/* A debugging function that can be called from gdb, for instance. */ +void +open_files () +{ + register int i; + int f, fd_table_size; + + fd_table_size = getdtablesize (); + + fprintf (stderr, "pid %ld open files:", (long)getpid ()); + for (i = 3; i < fd_table_size; i++) + { + if ((f = fcntl (i, F_GETFD, 0)) != -1) + fprintf (stderr, " %d (%s)", i, f ? "close" : "open"); + } + fprintf (stderr, "\n"); +} +#endif + +static void +async_redirect_stdin () +{ + int fd; + + fd = open ("/dev/null", O_RDONLY); + if (fd > 0) + { + dup2 (fd, 0); + close (fd); + } + else if (fd < 0) + internal_error (_("cannot redirect standard input from /dev/null: %s"), strerror (errno)); +} + +#define DESCRIBE_PID(pid) do { if (interactive) describe_pid (pid); } while (0) + +/* Execute the command passed in COMMAND, perhaps doing it asynchronously. + COMMAND is exactly what read_command () places into GLOBAL_COMMAND. + ASYNCHROUNOUS, if non-zero, says to do this command in the background. + PIPE_IN and PIPE_OUT are file descriptors saying where input comes + from and where it goes. They can have the value of NO_PIPE, which means + I/O is stdin/stdout. + FDS_TO_CLOSE is a list of file descriptors to close once the child has + been forked. This list often contains the unusable sides of pipes, etc. + + EXECUTION_SUCCESS or EXECUTION_FAILURE are the only possible + return values. Executing a command with nothing in it returns + EXECUTION_SUCCESS. */ +int +execute_command_internal (command, asynchronous, pipe_in, pipe_out, + fds_to_close) + COMMAND *command; + int asynchronous; + int pipe_in, pipe_out; + struct fd_bitmap *fds_to_close; +{ + int exec_result, user_subshell, invert, ignore_return, was_error_trap; + REDIRECT *my_undo_list, *exec_undo_list; + char *tcmd; + volatile int save_line_number; +#if defined (PROCESS_SUBSTITUTION) + volatile int ofifo, nfifo, osize, saved_fifo; + volatile char *ofifo_list; +#endif + + if (breaking || continuing) + return (last_command_exit_value); + if (command == 0 || read_but_dont_execute) + return (EXECUTION_SUCCESS); + + QUIT; + run_pending_traps (); + +#if 0 + if (running_trap == 0) +#endif + currently_executing_command = command; + + invert = (command->flags & CMD_INVERT_RETURN) != 0; + + /* If we're inverting the return value and `set -e' has been executed, + we don't want a failing command to inadvertently cause the shell + to exit. */ + if (exit_immediately_on_error && invert) /* XXX */ + command->flags |= CMD_IGNORE_RETURN; /* XXX */ + + exec_result = EXECUTION_SUCCESS; + + /* If a command was being explicitly run in a subshell, or if it is + a shell control-structure, and it has a pipe, then we do the command + in a subshell. */ + if (command->type == cm_subshell && (command->flags & CMD_NO_FORK)) + return (execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close)); + +#if defined (COPROCESS_SUPPORT) + if (command->type == cm_coproc) + return (last_command_exit_value = execute_coproc (command, pipe_in, pipe_out, fds_to_close)); +#endif + + user_subshell = command->type == cm_subshell || ((command->flags & CMD_WANT_SUBSHELL) != 0); + +#if defined (TIME_BEFORE_SUBSHELL) + if ((command->flags & CMD_TIME_PIPELINE) && user_subshell && asynchronous == 0) + { + command->flags |= CMD_FORCE_SUBSHELL; + exec_result = time_command (command, asynchronous, pipe_in, pipe_out, fds_to_close); + currently_executing_command = (COMMAND *)NULL; + return (exec_result); + } +#endif + + if (command->type == cm_subshell || + (command->flags & (CMD_WANT_SUBSHELL|CMD_FORCE_SUBSHELL)) || + (shell_control_structure (command->type) && + (pipe_out != NO_PIPE || pipe_in != NO_PIPE || asynchronous))) + { + pid_t paren_pid; + int s; + char *p; + + /* Fork a subshell, turn off the subshell bit, turn off job + control and call execute_command () on the command again. */ + if (command->type == cm_subshell) + line_number_for_err_trap = line_number = command->value.Subshell->line; /* XXX - save value? */ + /* Otherwise we defer setting line_number */ + tcmd = make_command_string (command); + paren_pid = make_child (p = savestring (tcmd), asynchronous); + + if (user_subshell && signal_is_trapped (ERROR_TRAP) && + signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + if (paren_pid == 0) + { +#if defined (JOB_CONTROL) + FREE (p); /* child doesn't use pointer */ +#endif + /* We want to run the exit trap for forced {} subshells, and we + want to note this before execute_in_subshell modifies the + COMMAND struct. Need to keep in mind that execute_in_subshell + runs the exit trap for () subshells itself. */ + /* This handles { command; } & */ + s = user_subshell == 0 && command->type == cm_group && pipe_in == NO_PIPE && pipe_out == NO_PIPE && asynchronous; + /* run exit trap for : | { ...; } and { ...; } | : */ + /* run exit trap for : | ( ...; ) and ( ...; ) | : */ + s += user_subshell == 0 && command->type == cm_group && (pipe_in != NO_PIPE || pipe_out != NO_PIPE) && asynchronous == 0; + + last_command_exit_value = execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close); + if (s) + subshell_exit (last_command_exit_value); + else + sh_exit (last_command_exit_value); + /* NOTREACHED */ + } + else + { + close_pipes (pipe_in, pipe_out); + +#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) + if (variable_context == 0) /* wait until shell function completes */ + unlink_fifo_list (); +#endif + /* If we are part of a pipeline, and not the end of the pipeline, + then we should simply return and let the last command in the + pipe be waited for. If we are not in a pipeline, or are the + last command in the pipeline, then we wait for the subshell + and return its exit status as usual. */ + if (pipe_out != NO_PIPE) + return (EXECUTION_SUCCESS); + + stop_pipeline (asynchronous, (COMMAND *)NULL); + + if (asynchronous == 0) + { + was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0; + invert = (command->flags & CMD_INVERT_RETURN) != 0; + ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0; + + exec_result = wait_for (paren_pid); + + /* If we have to, invert the return value. */ + if (invert) + exec_result = ((exec_result == EXECUTION_SUCCESS) + ? EXECUTION_FAILURE + : EXECUTION_SUCCESS); + + last_command_exit_value = exec_result; + if (user_subshell && was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS) + { + save_line_number = line_number; + line_number = line_number_for_err_trap; + run_error_trap (); + line_number = save_line_number; + } + + if (user_subshell && ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS) + { + run_pending_traps (); + jump_to_top_level (ERREXIT); + } + + return (last_command_exit_value); + } + else + { + DESCRIBE_PID (paren_pid); + + run_pending_traps (); + + /* Posix 2013 2.9.3.1: "the exit status of an asynchronous list + shall be zero." */ + last_command_exit_value = 0; + return (EXECUTION_SUCCESS); + } + } + } + +#if defined (COMMAND_TIMING) + if (command->flags & CMD_TIME_PIPELINE) + { + if (asynchronous) + { + command->flags |= CMD_FORCE_SUBSHELL; + exec_result = execute_command_internal (command, 1, pipe_in, pipe_out, fds_to_close); + } + else + { + exec_result = time_command (command, asynchronous, pipe_in, pipe_out, fds_to_close); +#if 0 + if (running_trap == 0) +#endif + currently_executing_command = (COMMAND *)NULL; + } + return (exec_result); + } +#endif /* COMMAND_TIMING */ + + if (shell_control_structure (command->type) && command->redirects) + stdin_redir = stdin_redirects (command->redirects); + +#if defined (PROCESS_SUBSTITUTION) +# if !defined (HAVE_DEV_FD) + reap_procsubs (); +# endif + + if (variable_context != 0) /* XXX - also if sourcelevel != 0? */ + { + ofifo = num_fifos (); + ofifo_list = copy_fifo_list ((int *)&osize); + begin_unwind_frame ("internal_fifos"); + add_unwind_protect (xfree, ofifo_list); + saved_fifo = 1; + } + else + saved_fifo = 0; +#endif + + /* Handle WHILE FOR CASE etc. with redirections. (Also '&' input + redirection.) */ + if (do_redirections (command->redirects, RX_ACTIVE|RX_UNDOABLE) != 0) + { + undo_partial_redirects (); + dispose_exec_redirects (); +#if defined (PROCESS_SUBSTITUTION) + if (saved_fifo) + { + free ((void *)ofifo_list); + discard_unwind_frame ("internal_fifos"); + } +#endif + return (last_command_exit_value = EXECUTION_FAILURE); + } + +#if 0 + if (redirection_undo_list) + { + /* XXX - why copy here? */ + my_undo_list = (REDIRECT *)copy_redirects (redirection_undo_list); + dispose_partial_redirects (); + } + else + my_undo_list = (REDIRECT *)NULL; +#else + my_undo_list = redirection_undo_list; + redirection_undo_list = (REDIRECT *)NULL; +#endif + +#if 0 + if (exec_redirection_undo_list) + { + /* XXX - why copy here? */ + exec_undo_list = (REDIRECT *)copy_redirects (exec_redirection_undo_list); + dispose_exec_redirects (); + } + else + exec_undo_list = (REDIRECT *)NULL; +#else + exec_undo_list = exec_redirection_undo_list; + exec_redirection_undo_list = (REDIRECT *)NULL; +#endif + + if (my_undo_list || exec_undo_list) + begin_unwind_frame ("loop_redirections"); + + if (my_undo_list) + add_unwind_protect ((Function *)cleanup_redirects, my_undo_list); + + if (exec_undo_list) + add_unwind_protect ((Function *)dispose_redirects, exec_undo_list); + + ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0; + + QUIT; + + switch (command->type) + { + case cm_simple: + { + save_line_number = line_number; + /* We can't rely on variables retaining their values across a + call to execute_simple_command if a longjmp occurs as the + result of a `return' builtin. This is true for sure with gcc. */ +#if defined (RECYCLES_PIDS) + last_made_pid = NO_PID; +#endif + was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0; + + if (ignore_return && command->value.Simple) + command->value.Simple->flags |= CMD_IGNORE_RETURN; + if (command->flags & CMD_STDIN_REDIR) + command->value.Simple->flags |= CMD_STDIN_REDIR; + + line_number_for_err_trap = line_number = command->value.Simple->line; + exec_result = + execute_simple_command (command->value.Simple, pipe_in, pipe_out, + asynchronous, fds_to_close); + line_number = save_line_number; + + /* The temporary environment should be used for only the simple + command immediately following its definition. */ + dispose_used_env_vars (); + +#if (defined (ultrix) && defined (mips)) || defined (C_ALLOCA) + /* Reclaim memory allocated with alloca () on machines which + may be using the alloca emulation code. */ + (void) alloca (0); +#endif /* (ultrix && mips) || C_ALLOCA */ + + /* If we forked to do the command, then we must wait_for () + the child. */ + + /* XXX - this is something to watch out for if there are problems + when the shell is compiled without job control. Don't worry about + whether or not last_made_pid == last_pid; already_making_children + tells us whether or not there are unwaited-for children to wait + for and reap. */ + if (already_making_children && pipe_out == NO_PIPE) + { + stop_pipeline (asynchronous, (COMMAND *)NULL); + + if (asynchronous) + { + DESCRIBE_PID (last_made_pid); + exec_result = EXECUTION_SUCCESS; + invert = 0; /* async commands always succeed */ + } + else +#if !defined (JOB_CONTROL) + /* Do not wait for asynchronous processes started from + startup files. */ + if (last_made_pid != NO_PID && last_made_pid != last_asynchronous_pid) +#else + if (last_made_pid != NO_PID) +#endif + /* When executing a shell function that executes other + commands, this causes the last simple command in + the function to be waited for twice. This also causes + subshells forked to execute builtin commands (e.g., in + pipelines) to be waited for twice. */ + exec_result = wait_for (last_made_pid); + } + } + + /* 2009/02/13 -- pipeline failure is processed elsewhere. This handles + only the failure of a simple command. We don't want to run the error + trap if the command run by the `command' builtin fails; we want to + defer that until the command builtin itself returns failure. */ + if (was_error_trap && ignore_return == 0 && invert == 0 && + pipe_in == NO_PIPE && pipe_out == NO_PIPE && + (command->value.Simple->flags & CMD_COMMAND_BUILTIN) == 0 && + exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + line_number = line_number_for_err_trap; + run_error_trap (); + line_number = save_line_number; + } + + if (ignore_return == 0 && invert == 0 && + ((posixly_correct && interactive == 0 && special_builtin_failed) || + (exit_immediately_on_error && pipe_in == NO_PIPE && pipe_out == NO_PIPE && exec_result != EXECUTION_SUCCESS))) + { + last_command_exit_value = exec_result; + run_pending_traps (); + + /* Undo redirections before running exit trap on the way out of + set -e. Report by Mark Farrell 5/19/2014 */ + if (exit_immediately_on_error && signal_is_trapped (0) && + unwind_protect_tag_on_stack ("saved-redirects")) + run_unwind_frame ("saved-redirects"); + + jump_to_top_level (ERREXIT); + } + + break; + + case cm_for: + if (ignore_return) + command->value.For->flags |= CMD_IGNORE_RETURN; + exec_result = execute_for_command (command->value.For); + break; + +#if defined (ARITH_FOR_COMMAND) + case cm_arith_for: + if (ignore_return) + command->value.ArithFor->flags |= CMD_IGNORE_RETURN; + exec_result = execute_arith_for_command (command->value.ArithFor); + break; +#endif + +#if defined (SELECT_COMMAND) + case cm_select: + if (ignore_return) + command->value.Select->flags |= CMD_IGNORE_RETURN; + exec_result = execute_select_command (command->value.Select); + break; +#endif + + case cm_case: + if (ignore_return) + command->value.Case->flags |= CMD_IGNORE_RETURN; + exec_result = execute_case_command (command->value.Case); + break; + + case cm_while: + if (ignore_return) + command->value.While->flags |= CMD_IGNORE_RETURN; + exec_result = execute_while_command (command->value.While); + break; + + case cm_until: + if (ignore_return) + command->value.While->flags |= CMD_IGNORE_RETURN; + exec_result = execute_until_command (command->value.While); + break; + + case cm_if: + if (ignore_return) + command->value.If->flags |= CMD_IGNORE_RETURN; + exec_result = execute_if_command (command->value.If); + break; + + case cm_group: + + /* This code can be executed from either of two paths: an explicit + '{}' command, or via a function call. If we are executed via a + function call, we have already taken care of the function being + executed in the background (down there in execute_simple_command ()), + and this command should *not* be marked as asynchronous. If we + are executing a regular '{}' group command, and asynchronous == 1, + we must want to execute the whole command in the background, so we + need a subshell, and we want the stuff executed in that subshell + (this group command) to be executed in the foreground of that + subshell (i.e. there will not be *another* subshell forked). + + What we do is to force a subshell if asynchronous, and then call + execute_command_internal again with asynchronous still set to 1, + but with the original group command, so the printed command will + look right. + + The code above that handles forking off subshells will note that + both subshell and async are on, and turn off async in the child + after forking the subshell (but leave async set in the parent, so + the normal call to describe_pid is made). This turning off + async is *crucial*; if it is not done, this will fall into an + infinite loop of executions through this spot in subshell after + subshell until the process limit is exhausted. */ + + if (asynchronous) + { + command->flags |= CMD_FORCE_SUBSHELL; + exec_result = + execute_command_internal (command, 1, pipe_in, pipe_out, + fds_to_close); + } + else + { + if (ignore_return && command->value.Group->command) + command->value.Group->command->flags |= CMD_IGNORE_RETURN; + exec_result = + execute_command_internal (command->value.Group->command, + asynchronous, pipe_in, pipe_out, + fds_to_close); + } + break; + + case cm_connection: + exec_result = execute_connection (command, asynchronous, + pipe_in, pipe_out, fds_to_close); + if (asynchronous) + invert = 0; /* XXX */ + + break; + +#if defined (DPAREN_ARITHMETIC) + case cm_arith: + was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0; + if (ignore_return) + command->value.Arith->flags |= CMD_IGNORE_RETURN; + line_number_for_err_trap = save_line_number = line_number; + exec_result = execute_arith_command (command->value.Arith); + line_number = save_line_number; + + if (was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + save_line_number = line_number; + line_number = line_number_for_err_trap; + run_error_trap (); + line_number = save_line_number; + } + + if (ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + run_pending_traps (); + jump_to_top_level (ERREXIT); + } + + break; +#endif + +#if defined (COND_COMMAND) + case cm_cond: + was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0; + if (ignore_return) + command->value.Cond->flags |= CMD_IGNORE_RETURN; + + line_number_for_err_trap = save_line_number = line_number; + exec_result = execute_cond_command (command->value.Cond); + line_number = save_line_number; + + if (was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + save_line_number = line_number; + line_number = line_number_for_err_trap; + run_error_trap (); + line_number = save_line_number; + } + + if (ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + run_pending_traps (); + jump_to_top_level (ERREXIT); + } + + break; +#endif + + case cm_function_def: + exec_result = execute_intern_function (command->value.Function_def->name, + command->value.Function_def); + break; + + default: + command_error ("execute_command", CMDERR_BADTYPE, command->type, 0); + } + + if (my_undo_list) + cleanup_redirects (my_undo_list); + + if (exec_undo_list) + dispose_redirects (exec_undo_list); + + if (my_undo_list || exec_undo_list) + discard_unwind_frame ("loop_redirections"); + +#if defined (PROCESS_SUBSTITUTION) + if (saved_fifo) + { + nfifo = num_fifos (); + if (nfifo > ofifo) + close_new_fifos ((char *)ofifo_list, osize); + free ((void *)ofifo_list); + discard_unwind_frame ("internal_fifos"); + } +#endif + + /* Invert the return value if we have to */ + if (invert) + exec_result = (exec_result == EXECUTION_SUCCESS) + ? EXECUTION_FAILURE + : EXECUTION_SUCCESS; + +#if defined (DPAREN_ARITHMETIC) || defined (COND_COMMAND) + /* This is where we set PIPESTATUS from the exit status of the appropriate + compound commands (the ones that look enough like simple commands to + cause confusion). We might be able to optimize by not doing this if + subshell_environment != 0. */ + switch (command->type) + { +# if defined (DPAREN_ARITHMETIC) + case cm_arith: +# endif +# if defined (COND_COMMAND) + case cm_cond: +# endif + set_pipestatus_from_exit (exec_result); + break; + default: + break; + } +#endif + + last_command_exit_value = exec_result; + run_pending_traps (); +#if 0 + if (running_trap == 0) +#endif + currently_executing_command = (COMMAND *)NULL; + + return (last_command_exit_value); +} + +#if defined (COMMAND_TIMING) + +#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY) +extern struct timeval *difftimeval __P((struct timeval *, struct timeval *, struct timeval *)); +extern struct timeval *addtimeval __P((struct timeval *, struct timeval *, struct timeval *)); +extern int timeval_to_cpu __P((struct timeval *, struct timeval *, struct timeval *)); +#endif + +#define POSIX_TIMEFORMAT "real %2R\nuser %2U\nsys %2S" +#define BASH_TIMEFORMAT "\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS" + +static const int precs[] = { 0, 100, 10, 1 }; + +/* Expand one `%'-prefixed escape sequence from a time format string. */ +static int +mkfmt (buf, prec, lng, sec, sec_fraction) + char *buf; + int prec, lng; + time_t sec; + int sec_fraction; +{ + time_t min; + char abuf[INT_STRLEN_BOUND(time_t) + 1]; + int ind, aind; + + ind = 0; + abuf[sizeof(abuf) - 1] = '\0'; + + /* If LNG is non-zero, we want to decompose SEC into minutes and seconds. */ + if (lng) + { + min = sec / 60; + sec %= 60; + aind = sizeof(abuf) - 2; + do + abuf[aind--] = (min % 10) + '0'; + while (min /= 10); + aind++; + while (abuf[aind]) + buf[ind++] = abuf[aind++]; + buf[ind++] = 'm'; + } + + /* Now add the seconds. */ + aind = sizeof (abuf) - 2; + do + abuf[aind--] = (sec % 10) + '0'; + while (sec /= 10); + aind++; + while (abuf[aind]) + buf[ind++] = abuf[aind++]; + + /* We want to add a decimal point and PREC places after it if PREC is + nonzero. PREC is not greater than 3. SEC_FRACTION is between 0 + and 999. */ + if (prec != 0) + { + buf[ind++] = locale_decpoint (); + for (aind = 1; aind <= prec; aind++) + { + buf[ind++] = (sec_fraction / precs[aind]) + '0'; + sec_fraction %= precs[aind]; + } + } + + if (lng) + buf[ind++] = 's'; + buf[ind] = '\0'; + + return (ind); +} + +/* Interpret the format string FORMAT, interpolating the following escape + sequences: + %[prec][l][RUS] + + where the optional `prec' is a precision, meaning the number of + characters after the decimal point, the optional `l' means to format + using minutes and seconds (MMmNN[.FF]s), like the `times' builtin', + and the last character is one of + + R number of seconds of `real' time + U number of seconds of `user' time + S number of seconds of `system' time + + An occurrence of `%%' in the format string is translated to a `%'. The + result is printed to FP, a pointer to a FILE. The other variables are + the seconds and thousandths of a second of real, user, and system time, + resectively. */ +static void +print_formatted_time (fp, format, rs, rsf, us, usf, ss, ssf, cpu) + FILE *fp; + char *format; + time_t rs; + int rsf; + time_t us; + int usf; + time_t ss; + int ssf, cpu; +{ + int prec, lng, len; + char *str, *s, ts[INT_STRLEN_BOUND (time_t) + sizeof ("mSS.FFFF")]; + time_t sum; + int sum_frac; + int sindex, ssize; + + len = strlen (format); + ssize = (len + 64) - (len % 64); + str = (char *)xmalloc (ssize); + sindex = 0; + + for (s = format; *s; s++) + { + if (*s != '%' || s[1] == '\0') + { + RESIZE_MALLOCED_BUFFER (str, sindex, 1, ssize, 64); + str[sindex++] = *s; + } + else if (s[1] == '%') + { + s++; + RESIZE_MALLOCED_BUFFER (str, sindex, 1, ssize, 64); + str[sindex++] = *s; + } + else if (s[1] == 'P') + { + s++; +#if 0 + /* clamp CPU usage at 100% */ + if (cpu > 10000) + cpu = 10000; +#endif + sum = cpu / 100; + sum_frac = (cpu % 100) * 10; + len = mkfmt (ts, 2, 0, sum, sum_frac); + RESIZE_MALLOCED_BUFFER (str, sindex, len, ssize, 64); + strcpy (str + sindex, ts); + sindex += len; + } + else + { + prec = 3; /* default is three places past the decimal point. */ + lng = 0; /* default is to not use minutes or append `s' */ + s++; + if (DIGIT (*s)) /* `precision' */ + { + prec = *s++ - '0'; + if (prec > 3) prec = 3; + } + if (*s == 'l') /* `length extender' */ + { + lng = 1; + s++; + } + if (*s == 'R' || *s == 'E') + len = mkfmt (ts, prec, lng, rs, rsf); + else if (*s == 'U') + len = mkfmt (ts, prec, lng, us, usf); + else if (*s == 'S') + len = mkfmt (ts, prec, lng, ss, ssf); + else + { + internal_error (_("TIMEFORMAT: `%c': invalid format character"), *s); + free (str); + return; + } + RESIZE_MALLOCED_BUFFER (str, sindex, len, ssize, 64); + strcpy (str + sindex, ts); + sindex += len; + } + } + + str[sindex] = '\0'; + fprintf (fp, "%s\n", str); + fflush (fp); + + free (str); +} + +static int +time_command (command, asynchronous, pipe_in, pipe_out, fds_to_close) + COMMAND *command; + int asynchronous, pipe_in, pipe_out; + struct fd_bitmap *fds_to_close; +{ + int rv, posix_time, old_flags, nullcmd, code; + time_t rs, us, ss; + int rsf, usf, ssf; + int cpu; + char *time_format; + volatile procenv_t save_top_level; + +#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY) + struct timeval real, user, sys; + struct timeval before, after; +# if defined (HAVE_STRUCT_TIMEZONE) + struct timezone dtz; /* posix doesn't define this */ +# endif + struct rusage selfb, selfa, kidsb, kidsa; /* a = after, b = before */ +#else +# if defined (HAVE_TIMES) + clock_t tbefore, tafter, real, user, sys; + struct tms before, after; +# endif +#endif + +#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY) +# if defined (HAVE_STRUCT_TIMEZONE) + gettimeofday (&before, &dtz); +# else + gettimeofday (&before, (void *)NULL); +# endif /* !HAVE_STRUCT_TIMEZONE */ + getrusage (RUSAGE_SELF, &selfb); + getrusage (RUSAGE_CHILDREN, &kidsb); +#else +# if defined (HAVE_TIMES) + tbefore = times (&before); +# endif +#endif + + posix_time = command && (command->flags & CMD_TIME_POSIX); + + nullcmd = (command == 0) || (command->type == cm_simple && command->value.Simple->words == 0 && command->value.Simple->redirects == 0); + if (posixly_correct && nullcmd) + { +#if defined (HAVE_GETRUSAGE) + selfb.ru_utime.tv_sec = kidsb.ru_utime.tv_sec = selfb.ru_stime.tv_sec = kidsb.ru_stime.tv_sec = 0; + selfb.ru_utime.tv_usec = kidsb.ru_utime.tv_usec = selfb.ru_stime.tv_usec = kidsb.ru_stime.tv_usec = 0; + before.tv_sec = shell_start_time; + before.tv_usec = 0; +#else + before.tms_utime = before.tms_stime = before.tms_cutime = before.tms_cstime = 0; + tbefore = shell_start_time; +#endif + } + + old_flags = command->flags; + COPY_PROCENV (top_level, save_top_level); + command->flags &= ~(CMD_TIME_PIPELINE|CMD_TIME_POSIX); + code = setjmp_nosigs (top_level); + if (code == NOT_JUMPED) + { + rv = execute_command_internal (command, asynchronous, pipe_in, pipe_out, fds_to_close); + command->flags = old_flags; + } + COPY_PROCENV (save_top_level, top_level); + + rs = us = ss = 0; + rsf = usf = ssf = cpu = 0; + +#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY) +# if defined (HAVE_STRUCT_TIMEZONE) + gettimeofday (&after, &dtz); +# else + gettimeofday (&after, (void *)NULL); +# endif /* !HAVE_STRUCT_TIMEZONE */ + getrusage (RUSAGE_SELF, &selfa); + getrusage (RUSAGE_CHILDREN, &kidsa); + + difftimeval (&real, &before, &after); + timeval_to_secs (&real, &rs, &rsf); + + addtimeval (&user, difftimeval(&after, &selfb.ru_utime, &selfa.ru_utime), + difftimeval(&before, &kidsb.ru_utime, &kidsa.ru_utime)); + timeval_to_secs (&user, &us, &usf); + + addtimeval (&sys, difftimeval(&after, &selfb.ru_stime, &selfa.ru_stime), + difftimeval(&before, &kidsb.ru_stime, &kidsa.ru_stime)); + timeval_to_secs (&sys, &ss, &ssf); + + cpu = timeval_to_cpu (&real, &user, &sys); +#else +# if defined (HAVE_TIMES) + tafter = times (&after); + + real = tafter - tbefore; + clock_t_to_secs (real, &rs, &rsf); + + user = (after.tms_utime - before.tms_utime) + (after.tms_cutime - before.tms_cutime); + clock_t_to_secs (user, &us, &usf); + + sys = (after.tms_stime - before.tms_stime) + (after.tms_cstime - before.tms_cstime); + clock_t_to_secs (sys, &ss, &ssf); + + cpu = (real == 0) ? 0 : ((user + sys) * 10000) / real; + +# else + rs = us = ss = 0; + rsf = usf = ssf = cpu = 0; +# endif +#endif + + if (posix_time) + time_format = POSIX_TIMEFORMAT; + else if ((time_format = get_string_value ("TIMEFORMAT")) == 0) + { + if (posixly_correct && nullcmd) + time_format = "user\t%2lU\nsys\t%2lS"; + else + time_format = BASH_TIMEFORMAT; + } + + if (time_format && *time_format) + print_formatted_time (stderr, time_format, rs, rsf, us, usf, ss, ssf, cpu); + + if (code) + sh_longjmp (top_level, code); + + return rv; +} +#endif /* COMMAND_TIMING */ + +/* Execute a command that's supposed to be in a subshell. This must be + called after make_child and we must be running in the child process. + The caller will return or exit() immediately with the value this returns. */ +static int +execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close) + COMMAND *command; + int asynchronous; + int pipe_in, pipe_out; + struct fd_bitmap *fds_to_close; +{ + volatile int user_subshell, user_coproc, invert; + int return_code, function_value, should_redir_stdin, ois, result; + volatile COMMAND *tcom; + + USE_VAR(user_subshell); + USE_VAR(user_coproc); + USE_VAR(invert); + USE_VAR(tcom); + USE_VAR(asynchronous); + + subshell_level++; + should_redir_stdin = (asynchronous && (command->flags & CMD_STDIN_REDIR) && + pipe_in == NO_PIPE && + stdin_redirects (command->redirects) == 0); + + invert = (command->flags & CMD_INVERT_RETURN) != 0; + user_subshell = command->type == cm_subshell || ((command->flags & CMD_WANT_SUBSHELL) != 0); + user_coproc = command->type == cm_coproc; + + command->flags &= ~(CMD_FORCE_SUBSHELL | CMD_WANT_SUBSHELL | CMD_INVERT_RETURN); + + /* If a command is asynchronous in a subshell (like ( foo ) & or + the special case of an asynchronous GROUP command where the + the subshell bit is turned on down in case cm_group: below), + turn off `asynchronous', so that two subshells aren't spawned. + XXX - asynchronous used to be set to 0 in this block, but that + means that setup_async_signals was never run. Now it's set to + 0 after subshell_environment is set appropriately and setup_async_signals + is run. + + This seems semantically correct to me. For example, + ( foo ) & seems to say ``do the command `foo' in a subshell + environment, but don't wait for that subshell to finish'', + and "{ foo ; bar ; } &" seems to me to be like functions or + builtins in the background, which executed in a subshell + environment. I just don't see the need to fork two subshells. */ + + /* Don't fork again, we are already in a subshell. A `doubly + async' shell is not interactive, however. */ + if (asynchronous) + { +#if defined (JOB_CONTROL) + /* If a construct like ( exec xxx yyy ) & is given while job + control is active, we want to prevent exec from putting the + subshell back into the original process group, carefully + undoing all the work we just did in make_child. */ + original_pgrp = -1; +#endif /* JOB_CONTROL */ + ois = interactive_shell; + interactive_shell = 0; + /* This test is to prevent alias expansion by interactive shells that + run `(command) &' but to allow scripts that have enabled alias + expansion with `shopt -s expand_alias' to continue to expand + aliases. */ + if (ois != interactive_shell) + expand_aliases = 0; + } + + /* Subshells are neither login nor interactive. */ + login_shell = interactive = 0; + + /* And we're no longer in a loop. See Posix interp 842 (we are not in the + "same execution environment"). */ + if (shell_compatibility_level > 44) + loop_level = 0; + + if (user_subshell) + { + subshell_environment = SUBSHELL_PAREN; /* XXX */ + if (asynchronous) + subshell_environment |= SUBSHELL_ASYNC; + } + else + { + subshell_environment = 0; /* XXX */ + if (asynchronous) + subshell_environment |= SUBSHELL_ASYNC; + if (pipe_in != NO_PIPE || pipe_out != NO_PIPE) + subshell_environment |= SUBSHELL_PIPE; + if (user_coproc) + subshell_environment |= SUBSHELL_COPROC; + } + + reset_terminating_signals (); /* in sig.c */ + /* Cancel traps, in trap.c. */ + /* Reset the signal handlers in the child, but don't free the + trap strings. Set a flag noting that we have to free the + trap strings if we run trap to change a signal disposition. */ + reset_signal_handlers (); + subshell_environment |= SUBSHELL_RESETTRAP; +#if 0 /* TAG:bash-5.1 */ + /* We are in a subshell, so forget that we are running a trap handler or + that the signal handler has changed (we haven't changed it!) */ + if (running_trap > 0) + { + run_trap_cleanup (running_trap - 1); + running_trap = 0; + } +#endif + + /* Make sure restore_original_signals doesn't undo the work done by + make_child to ensure that asynchronous children are immune to SIGINT + and SIGQUIT. Turn off asynchronous to make sure more subshells are + not spawned. */ + if (asynchronous) + { + setup_async_signals (); + asynchronous = 0; + } + else + set_sigint_handler (); + +#if defined (JOB_CONTROL) + set_sigchld_handler (); +#endif /* JOB_CONTROL */ + + /* Delete all traces that there were any jobs running. This is + only for subshells. */ + without_job_control (); + + if (fds_to_close) + close_fd_bitmap (fds_to_close); + + do_piping (pipe_in, pipe_out); + +#if defined (COPROCESS_SUPPORT) + coproc_closeall (); +#endif + + /* If this is a user subshell, set a flag if stdin was redirected. + This is used later to decide whether to redirect fd 0 to + /dev/null for async commands in the subshell. This adds more + sh compatibility, but I'm not sure it's the right thing to do. + Note that an input pipe to a compound command suffices to inhibit + the implicit /dev/null redirection for asynchronous commands + executed as part of that compound command. */ + if (user_subshell) + { + stdin_redir = stdin_redirects (command->redirects) || pipe_in != NO_PIPE; +#if 0 + restore_default_signal (EXIT_TRAP); /* XXX - reset_signal_handlers above */ +#endif + } + else if (shell_control_structure (command->type) && pipe_in != NO_PIPE) + stdin_redir = 1; + + /* If this is an asynchronous command (command &), we want to + redirect the standard input from /dev/null in the absence of + any specific redirection involving stdin. */ + if (should_redir_stdin && stdin_redir == 0) + async_redirect_stdin (); + +#if 0 + /* XXX - TAG:bash-5.1 */ + if (user_subshell && command->type == cm_subshell) + optimize_subshell_command (command->value.Subshell->command); +#endif + + /* Do redirections, then dispose of them before recursive call. */ + if (command->redirects) + { + if (do_redirections (command->redirects, RX_ACTIVE) != 0) + exit (invert ? EXECUTION_SUCCESS : EXECUTION_FAILURE); + + dispose_redirects (command->redirects); + command->redirects = (REDIRECT *)NULL; + } + + if (command->type == cm_subshell) + tcom = command->value.Subshell->command; + else if (user_coproc) + tcom = command->value.Coproc->command; + else + tcom = command; + + if (command->flags & CMD_TIME_PIPELINE) + tcom->flags |= CMD_TIME_PIPELINE; + if (command->flags & CMD_TIME_POSIX) + tcom->flags |= CMD_TIME_POSIX; + + /* Make sure the subshell inherits any CMD_IGNORE_RETURN flag. */ + if ((command->flags & CMD_IGNORE_RETURN) && tcom != command) + tcom->flags |= CMD_IGNORE_RETURN; + + /* If this is a simple command, tell execute_disk_command that it + might be able to get away without forking and simply exec. + This means things like ( sleep 10 ) will only cause one fork. + If we're timing the command or inverting its return value, however, + we cannot do this optimization. */ + if ((user_subshell || user_coproc) && (tcom->type == cm_simple || tcom->type == cm_subshell) && + ((tcom->flags & CMD_TIME_PIPELINE) == 0) && + ((tcom->flags & CMD_INVERT_RETURN) == 0)) + { + tcom->flags |= CMD_NO_FORK; + if (tcom->type == cm_simple) + tcom->value.Simple->flags |= CMD_NO_FORK; + } + + invert = (tcom->flags & CMD_INVERT_RETURN) != 0; + tcom->flags &= ~CMD_INVERT_RETURN; + + result = setjmp_nosigs (top_level); + + /* If we're inside a function while executing this subshell, we + need to handle a possible `return'. */ + function_value = 0; + if (return_catch_flag) + function_value = setjmp_nosigs (return_catch); + + /* If we're going to exit the shell, we don't want to invert the return + status. */ + if (result == EXITPROG) + invert = 0, return_code = last_command_exit_value; + else if (result) + return_code = (last_command_exit_value == EXECUTION_SUCCESS) ? EXECUTION_FAILURE : last_command_exit_value; + else if (function_value) + return_code = return_catch_value; + else + return_code = execute_command_internal ((COMMAND *)tcom, asynchronous, NO_PIPE, NO_PIPE, fds_to_close); + + /* If we are asked to, invert the return value. */ + if (invert) + return_code = (return_code == EXECUTION_SUCCESS) ? EXECUTION_FAILURE + : EXECUTION_SUCCESS; + + + /* If we were explicitly placed in a subshell with (), we need + to do the `shell cleanup' things, such as running traps[0]. */ + if (user_subshell && signal_is_trapped (0)) + { + last_command_exit_value = return_code; + return_code = run_exit_trap (); + } + +#if 0 + subshell_level--; /* don't bother, caller will just exit */ +#endif + return (return_code); + /* NOTREACHED */ +} + +#if defined (COPROCESS_SUPPORT) +#define COPROC_MAX 16 + +typedef struct cpelement + { + struct cpelement *next; + struct coproc *coproc; + } +cpelement_t; + +typedef struct cplist + { + struct cpelement *head; + struct cpelement *tail; + int ncoproc; + int lock; + } +cplist_t; + +static struct cpelement *cpe_alloc __P((struct coproc *)); +static void cpe_dispose __P((struct cpelement *)); +static struct cpelement *cpl_add __P((struct coproc *)); +static struct cpelement *cpl_delete __P((pid_t)); +static void cpl_reap __P((void)); +static void cpl_flush __P((void)); +static void cpl_closeall __P((void)); +static struct cpelement *cpl_search __P((pid_t)); +static struct cpelement *cpl_searchbyname __P((const char *)); +static void cpl_prune __P((void)); + +static void coproc_free __P((struct coproc *)); + +/* Will go away when there is fully-implemented support for multiple coprocs. */ +Coproc sh_coproc = { 0, NO_PID, -1, -1, 0, 0, 0, 0, 0 }; + +cplist_t coproc_list = {0, 0, 0}; + +/* Functions to manage the list of coprocs */ + +static struct cpelement * +cpe_alloc (cp) + Coproc *cp; +{ + struct cpelement *cpe; + + cpe = (struct cpelement *)xmalloc (sizeof (struct cpelement)); + cpe->coproc = cp; + cpe->next = (struct cpelement *)0; + return cpe; +} + +static void +cpe_dispose (cpe) + struct cpelement *cpe; +{ + free (cpe); +} + +static struct cpelement * +cpl_add (cp) + Coproc *cp; +{ + struct cpelement *cpe; + + cpe = cpe_alloc (cp); + + if (coproc_list.head == 0) + { + coproc_list.head = coproc_list.tail = cpe; + coproc_list.ncoproc = 0; /* just to make sure */ + } + else + { + coproc_list.tail->next = cpe; + coproc_list.tail = cpe; + } + coproc_list.ncoproc++; + + return cpe; +} + +static struct cpelement * +cpl_delete (pid) + pid_t pid; +{ + struct cpelement *prev, *p; + + for (prev = p = coproc_list.head; p; prev = p, p = p->next) + if (p->coproc->c_pid == pid) + { + prev->next = p->next; /* remove from list */ + break; + } + + if (p == 0) + return 0; /* not found */ + +#if defined (DEBUG) + itrace("cpl_delete: deleting %d", pid); +#endif + + /* Housekeeping in the border cases. */ + if (p == coproc_list.head) + coproc_list.head = coproc_list.head->next; + else if (p == coproc_list.tail) + coproc_list.tail = prev; + + coproc_list.ncoproc--; + if (coproc_list.ncoproc == 0) + coproc_list.head = coproc_list.tail = 0; + else if (coproc_list.ncoproc == 1) + coproc_list.tail = coproc_list.head; /* just to make sure */ + + return (p); +} + +static void +cpl_reap () +{ + struct cpelement *p, *next, *nh, *nt; + + /* Build a new list by removing dead coprocs and fix up the coproc_list + pointers when done. */ + nh = nt = next = (struct cpelement *)0; + for (p = coproc_list.head; p; p = next) + { + next = p->next; + if (p->coproc->c_flags & COPROC_DEAD) + { + coproc_list.ncoproc--; /* keep running count, fix up pointers later */ + +#if defined (DEBUG) + itrace("cpl_reap: deleting %d", p->coproc->c_pid); +#endif + + coproc_dispose (p->coproc); + cpe_dispose (p); + } + else if (nh == 0) + nh = nt = p; + else + { + nt->next = p; + nt = nt->next; + } + } + + if (coproc_list.ncoproc == 0) + coproc_list.head = coproc_list.tail = 0; + else + { + if (nt) + nt->next = 0; + coproc_list.head = nh; + coproc_list.tail = nt; + if (coproc_list.ncoproc == 1) + coproc_list.tail = coproc_list.head; /* just to make sure */ + } +} + +/* Clear out the list of saved statuses */ +static void +cpl_flush () +{ + struct cpelement *cpe, *p; + + for (cpe = coproc_list.head; cpe; ) + { + p = cpe; + cpe = cpe->next; + + coproc_dispose (p->coproc); + cpe_dispose (p); + } + + coproc_list.head = coproc_list.tail = 0; + coproc_list.ncoproc = 0; +} + +static void +cpl_closeall () +{ + struct cpelement *cpe; + + for (cpe = coproc_list.head; cpe; cpe = cpe->next) + coproc_close (cpe->coproc); +} + +static void +cpl_fdchk (fd) + int fd; +{ + struct cpelement *cpe; + + for (cpe = coproc_list.head; cpe; cpe = cpe->next) + coproc_checkfd (cpe->coproc, fd); +} + +/* Search for PID in the list of coprocs; return the cpelement struct if + found. If not found, return NULL. */ +static struct cpelement * +cpl_search (pid) + pid_t pid; +{ + struct cpelement *cpe; + + for (cpe = coproc_list.head ; cpe; cpe = cpe->next) + if (cpe->coproc->c_pid == pid) + return cpe; + return (struct cpelement *)NULL; +} + +/* Search for the coproc named NAME in the list of coprocs; return the + cpelement struct if found. If not found, return NULL. */ +static struct cpelement * +cpl_searchbyname (name) + const char *name; +{ + struct cpelement *cp; + + for (cp = coproc_list.head ; cp; cp = cp->next) + if (STREQ (cp->coproc->c_name, name)) + return cp; + return (struct cpelement *)NULL; +} + +static pid_t +cpl_firstactive () +{ + struct cpelement *cpe; + + for (cpe = coproc_list.head ; cpe; cpe = cpe->next) + if ((cpe->coproc->c_flags & COPROC_DEAD) == 0) + return cpe->coproc->c_pid; + return (pid_t)NO_PID; +} + +#if 0 +static void +cpl_prune () +{ + struct cpelement *cp; + + while (coproc_list.head && coproc_list.ncoproc > COPROC_MAX) + { + cp = coproc_list.head; + coproc_list.head = coproc_list.head->next; + coproc_dispose (cp->coproc); + cpe_dispose (cp); + coproc_list.ncoproc--; + } +} +#endif + +/* These currently use a single global "shell coproc" but are written in a + way to not preclude additional coprocs later (using the list management + package above). */ + +struct coproc * +getcoprocbypid (pid) + pid_t pid; +{ +#if MULTIPLE_COPROCS + struct cpelement *p; + + p = cpl_search (pid); + return (p ? p->coproc : 0); +#else + return (pid == sh_coproc.c_pid ? &sh_coproc : 0); +#endif +} + +struct coproc * +getcoprocbyname (name) + const char *name; +{ +#if MULTIPLE_COPROCS + struct cpelement *p; + + p = cpl_searchbyname (name); + return (p ? p->coproc : 0); +#else + return ((sh_coproc.c_name && STREQ (sh_coproc.c_name, name)) ? &sh_coproc : 0); +#endif +} + +void +coproc_init (cp) + struct coproc *cp; +{ + cp->c_name = 0; + cp->c_pid = NO_PID; + cp->c_rfd = cp->c_wfd = -1; + cp->c_rsave = cp->c_wsave = -1; + cp->c_flags = cp->c_status = cp->c_lock = 0; +} + +struct coproc * +coproc_alloc (name, pid) + char *name; + pid_t pid; +{ + struct coproc *cp; + +#if MULTIPLE_COPROCS + cp = (struct coproc *)xmalloc (sizeof (struct coproc)); +#else + cp = &sh_coproc; +#endif + coproc_init (cp); + cp->c_lock = 2; + + cp->c_pid = pid; + cp->c_name = savestring (name); +#if MULTIPLE_COPROCS + cpl_add (cp); +#endif + cp->c_lock = 0; + return (cp); +} + +static void +coproc_free (cp) + struct coproc *cp; +{ + free (cp); +} + +void +coproc_dispose (cp) + struct coproc *cp; +{ + sigset_t set, oset; + + if (cp == 0) + return; + + BLOCK_SIGNAL (SIGCHLD, set, oset); + cp->c_lock = 3; + coproc_unsetvars (cp); + FREE (cp->c_name); + coproc_close (cp); +#if MULTIPLE_COPROCS + coproc_free (cp); +#else + coproc_init (cp); + cp->c_lock = 0; +#endif + UNBLOCK_SIGNAL (oset); +} + +/* Placeholder for now. Will require changes for multiple coprocs */ +void +coproc_flush () +{ +#if MULTIPLE_COPROCS + cpl_flush (); +#else + coproc_dispose (&sh_coproc); +#endif +} + +void +coproc_close (cp) + struct coproc *cp; +{ + if (cp->c_rfd >= 0) + { + close (cp->c_rfd); + cp->c_rfd = -1; + } + if (cp->c_wfd >= 0) + { + close (cp->c_wfd); + cp->c_wfd = -1; + } + cp->c_rsave = cp->c_wsave = -1; +} + +void +coproc_closeall () +{ +#if MULTIPLE_COPROCS + cpl_closeall (); +#else + coproc_close (&sh_coproc); /* XXX - will require changes for multiple coprocs */ +#endif +} + +void +coproc_reap () +{ +#if MULTIPLE_COPROCS + cpl_reap (); +#else + struct coproc *cp; + + cp = &sh_coproc; /* XXX - will require changes for multiple coprocs */ + if (cp && (cp->c_flags & COPROC_DEAD)) + coproc_dispose (cp); +#endif +} + +void +coproc_rclose (cp, fd) + struct coproc *cp; + int fd; +{ + if (cp->c_rfd >= 0 && cp->c_rfd == fd) + { + close (cp->c_rfd); + cp->c_rfd = -1; + } +} + +void +coproc_wclose (cp, fd) + struct coproc *cp; + int fd; +{ + if (cp->c_wfd >= 0 && cp->c_wfd == fd) + { + close (cp->c_wfd); + cp->c_wfd = -1; + } +} + +void +coproc_checkfd (cp, fd) + struct coproc *cp; + int fd; +{ + int update; + + update = 0; + if (cp->c_rfd >= 0 && cp->c_rfd == fd) + update = cp->c_rfd = -1; + if (cp->c_wfd >= 0 && cp->c_wfd == fd) + update = cp->c_wfd = -1; + if (update) + coproc_setvars (cp); +} + +void +coproc_fdchk (fd) + int fd; +{ +#if MULTIPLE_COPROCS + cpl_fdchk (fd); +#else + coproc_checkfd (&sh_coproc, fd); +#endif +} + +void +coproc_fdclose (cp, fd) + struct coproc *cp; + int fd; +{ + coproc_rclose (cp, fd); + coproc_wclose (cp, fd); + coproc_setvars (cp); +} + +void +coproc_fdsave (cp) + struct coproc *cp; +{ + cp->c_rsave = cp->c_rfd; + cp->c_wsave = cp->c_wfd; +} + +void +coproc_fdrestore (cp) + struct coproc *cp; +{ + cp->c_rfd = cp->c_rsave; + cp->c_wfd = cp->c_wsave; +} + +static void +coproc_setstatus (cp, status) + struct coproc *cp; + int status; +{ + cp->c_lock = 4; + cp->c_status = status; + cp->c_flags |= COPROC_DEAD; + cp->c_flags &= ~COPROC_RUNNING; + /* Don't dispose the coproc or unset the COPROC_XXX variables because + this is executed in a signal handler context. Wait until coproc_reap + takes care of it. */ + cp->c_lock = 0; +} + +void +coproc_pidchk (pid, status) + pid_t pid; + int status; +{ + struct coproc *cp; + +#if MULTIPLE_COPROCS + struct cpelement *cpe; + + /* We're not disposing the coproc because this is executed in a signal + handler context */ + cpe = cpl_search (pid); + cp = cpe ? cpe->coproc : 0; +#else + cp = getcoprocbypid (pid); +#endif + if (cp) + coproc_setstatus (cp, status); +} + +pid_t +coproc_active () +{ +#if MULTIPLE_COPROCS + return (cpl_firstactive ()); +#else + return ((sh_coproc.c_flags & COPROC_DEAD) ? NO_PID : sh_coproc.c_pid); +#endif +} +void +coproc_setvars (cp) + struct coproc *cp; +{ + SHELL_VAR *v; + char *namevar, *t; + int l; + WORD_DESC w; +#if defined (ARRAY_VARS) + arrayind_t ind; +#endif + + if (cp->c_name == 0) + return; + + /* We could do more here but right now we only check the name, warn if it's + not a valid identifier, and refuse to create variables with invalid names + if a coproc with such a name is supplied. */ + w.word = cp->c_name; + w.flags = 0; + if (check_identifier (&w, 1) == 0) + return; + + l = strlen (cp->c_name); + namevar = xmalloc (l + 16); + +#if defined (ARRAY_VARS) + v = find_variable (cp->c_name); + + /* This is the same code as in find_or_make_array_variable */ + if (v == 0) + { + v = find_variable_nameref_for_create (cp->c_name, 1); + if (v == INVALID_NAMEREF_VALUE) + { + free (namevar); + return; + } + if (v && nameref_p (v)) + { + free (cp->c_name); + cp->c_name = savestring (nameref_cell (v)); + v = make_new_array_variable (cp->c_name); + } + } + + if (v && (readonly_p (v) || noassign_p (v))) + { + if (readonly_p (v)) + err_readonly (cp->c_name); + free (namevar); + return; + } + if (v == 0) + v = make_new_array_variable (cp->c_name); + if (array_p (v) == 0) + v = convert_var_to_array (v); + + t = itos (cp->c_rfd); + ind = 0; + v = bind_array_variable (cp->c_name, ind, t, 0); + free (t); + + t = itos (cp->c_wfd); + ind = 1; + v = bind_array_variable (cp->c_name, ind, t, 0); + free (t); +#else + sprintf (namevar, "%s_READ", cp->c_name); + t = itos (cp->c_rfd); + bind_variable (namevar, t, 0); + free (t); + sprintf (namevar, "%s_WRITE", cp->c_name); + t = itos (cp->c_wfd); + bind_variable (namevar, t, 0); + free (t); +#endif + + sprintf (namevar, "%s_PID", cp->c_name); + t = itos (cp->c_pid); + v = bind_variable (namevar, t, 0); + free (t); + + free (namevar); +} + +void +coproc_unsetvars (cp) + struct coproc *cp; +{ + int l; + char *namevar; + + if (cp->c_name == 0) + return; + + l = strlen (cp->c_name); + namevar = xmalloc (l + 16); + + sprintf (namevar, "%s_PID", cp->c_name); + unbind_variable_noref (namevar); + +#if defined (ARRAY_VARS) + check_unbind_variable (cp->c_name); +#else + sprintf (namevar, "%s_READ", cp->c_name); + unbind_variable (namevar); + sprintf (namevar, "%s_WRITE", cp->c_name); + unbind_variable (namevar); +#endif + + free (namevar); +} + +static int +execute_coproc (command, pipe_in, pipe_out, fds_to_close) + COMMAND *command; + int pipe_in, pipe_out; + struct fd_bitmap *fds_to_close; +{ + int rpipe[2], wpipe[2], estat, invert; + pid_t coproc_pid; + Coproc *cp; + char *tcmd, *p, *name; + sigset_t set, oset; + + /* XXX -- can be removed after changes to handle multiple coprocs */ +#if !MULTIPLE_COPROCS + if (sh_coproc.c_pid != NO_PID && (sh_coproc.c_rfd >= 0 || sh_coproc.c_wfd >= 0)) + internal_warning (_("execute_coproc: coproc [%d:%s] still exists"), sh_coproc.c_pid, sh_coproc.c_name); + coproc_init (&sh_coproc); +#endif + + invert = (command->flags & CMD_INVERT_RETURN) != 0; + + /* expand name without splitting - could make this dependent on a shopt option */ + name = expand_string_unsplit_to_string (command->value.Coproc->name, 0); + /* Optional check -- could be relaxed */ + if (legal_identifier (name) == 0) + { + internal_error (_("`%s': not a valid identifier"), name); + return (invert ? EXECUTION_SUCCESS : EXECUTION_FAILURE); + } + else + { + free (command->value.Coproc->name); + command->value.Coproc->name = name; + } + + command_string_index = 0; + tcmd = make_command_string (command); + + sh_openpipe ((int *)&rpipe); /* 0 = parent read, 1 = child write */ + sh_openpipe ((int *)&wpipe); /* 0 = child read, 1 = parent write */ + + BLOCK_SIGNAL (SIGCHLD, set, oset); + + coproc_pid = make_child (p = savestring (tcmd), 1); + + if (coproc_pid == 0) + { + close (rpipe[0]); + close (wpipe[1]); + +#if defined (JOB_CONTROL) + FREE (p); +#endif + + UNBLOCK_SIGNAL (oset); + estat = execute_in_subshell (command, 1, wpipe[0], rpipe[1], fds_to_close); + + fflush (stdout); + fflush (stderr); + + exit (estat); + } + + close (rpipe[1]); + close (wpipe[0]); + + cp = coproc_alloc (command->value.Coproc->name, coproc_pid); + cp->c_rfd = rpipe[0]; + cp->c_wfd = wpipe[1]; + + cp->c_flags |= COPROC_RUNNING; + + SET_CLOSE_ON_EXEC (cp->c_rfd); + SET_CLOSE_ON_EXEC (cp->c_wfd); + + coproc_setvars (cp); + + UNBLOCK_SIGNAL (oset); + +#if 0 + itrace ("execute_coproc (%s): [%d] %s", command->value.Coproc->name, coproc_pid, the_printed_command); +#endif + + close_pipes (pipe_in, pipe_out); +#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) + unlink_fifo_list (); +#endif + stop_pipeline (1, (COMMAND *)NULL); + DESCRIBE_PID (coproc_pid); + run_pending_traps (); + + return (invert ? EXECUTION_FAILURE : EXECUTION_SUCCESS); +} +#endif + +static void +restore_stdin (s) + int s; +{ + dup2 (s, 0); + close (s); +} + +/* Catch-all cleanup function for lastpipe code for unwind-protects */ +static void +lastpipe_cleanup (s) + int s; +{ + set_jobs_list_frozen (s); +} + +static int +execute_pipeline (command, asynchronous, pipe_in, pipe_out, fds_to_close) + COMMAND *command; + int asynchronous, pipe_in, pipe_out; + struct fd_bitmap *fds_to_close; +{ + int prev, fildes[2], new_bitmap_size, dummyfd, ignore_return, exec_result; + int lstdin, lastpipe_flag, lastpipe_jid, old_frozen; + COMMAND *cmd; + struct fd_bitmap *fd_bitmap; + pid_t lastpid; + +#if defined (JOB_CONTROL) + sigset_t set, oset; + BLOCK_CHILD (set, oset); +#endif /* JOB_CONTROL */ + + ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0; + + prev = pipe_in; + cmd = command; + + while (cmd && cmd->type == cm_connection && + cmd->value.Connection && cmd->value.Connection->connector == '|') + { + /* Make a pipeline between the two commands. */ + if (pipe (fildes) < 0) + { + sys_error (_("pipe error")); +#if defined (JOB_CONTROL) + terminate_current_pipeline (); + kill_current_pipeline (); + UNBLOCK_CHILD (oset); +#endif /* JOB_CONTROL */ + last_command_exit_value = EXECUTION_FAILURE; + /* The unwind-protects installed below will take care + of closing all of the open file descriptors. */ + throw_to_top_level (); + return (EXECUTION_FAILURE); /* XXX */ + } + + /* Here is a problem: with the new file close-on-exec + code, the read end of the pipe (fildes[0]) stays open + in the first process, so that process will never get a + SIGPIPE. There is no way to signal the first process + that it should close fildes[0] after forking, so it + remains open. No SIGPIPE is ever sent because there + is still a file descriptor open for reading connected + to the pipe. We take care of that here. This passes + around a bitmap of file descriptors that must be + closed after making a child process in execute_simple_command. */ + + /* We need fd_bitmap to be at least as big as fildes[0]. + If fildes[0] is less than fds_to_close->size, then + use fds_to_close->size. */ + new_bitmap_size = (fildes[0] < fds_to_close->size) + ? fds_to_close->size + : fildes[0] + 8; + + fd_bitmap = new_fd_bitmap (new_bitmap_size); + + /* Now copy the old information into the new bitmap. */ + xbcopy ((char *)fds_to_close->bitmap, (char *)fd_bitmap->bitmap, fds_to_close->size); + + /* And mark the pipe file descriptors to be closed. */ + fd_bitmap->bitmap[fildes[0]] = 1; + + /* In case there are pipe or out-of-processes errors, we + want all these file descriptors to be closed when + unwind-protects are run, and the storage used for the + bitmaps freed up. */ + begin_unwind_frame ("pipe-file-descriptors"); + add_unwind_protect (dispose_fd_bitmap, fd_bitmap); + add_unwind_protect (close_fd_bitmap, fd_bitmap); + if (prev >= 0) + add_unwind_protect (close, prev); + dummyfd = fildes[1]; + add_unwind_protect (close, dummyfd); + +#if defined (JOB_CONTROL) + add_unwind_protect (restore_signal_mask, &oset); +#endif /* JOB_CONTROL */ + + if (ignore_return && cmd->value.Connection->first) + cmd->value.Connection->first->flags |= CMD_IGNORE_RETURN; + execute_command_internal (cmd->value.Connection->first, asynchronous, + prev, fildes[1], fd_bitmap); + + if (prev >= 0) + close (prev); + + prev = fildes[0]; + close (fildes[1]); + + dispose_fd_bitmap (fd_bitmap); + discard_unwind_frame ("pipe-file-descriptors"); + + cmd = cmd->value.Connection->second; + } + + lastpid = last_made_pid; + + /* Now execute the rightmost command in the pipeline. */ + if (ignore_return && cmd) + cmd->flags |= CMD_IGNORE_RETURN; + + lastpipe_flag = 0; + + begin_unwind_frame ("lastpipe-exec"); + lstdin = -1; + /* If the `lastpipe' option is set with shopt, and job control is not + enabled, execute the last element of non-async pipelines in the + current shell environment. */ + if (lastpipe_opt && job_control == 0 && asynchronous == 0 && pipe_out == NO_PIPE && prev > 0) + { + lstdin = move_to_high_fd (0, 1, -1); + if (lstdin > 0) + { + do_piping (prev, pipe_out); + prev = NO_PIPE; + add_unwind_protect (restore_stdin, lstdin); + lastpipe_flag = 1; + old_frozen = freeze_jobs_list (); + lastpipe_jid = stop_pipeline (0, (COMMAND *)NULL); /* XXX */ + add_unwind_protect (lastpipe_cleanup, old_frozen); + } + if (cmd) + cmd->flags |= CMD_LASTPIPE; + } + if (prev >= 0) + add_unwind_protect (close, prev); + + exec_result = execute_command_internal (cmd, asynchronous, prev, pipe_out, fds_to_close); + + if (lstdin > 0) + restore_stdin (lstdin); + + if (prev >= 0) + close (prev); + +#if defined (JOB_CONTROL) + UNBLOCK_CHILD (oset); +#endif + + QUIT; + + if (lastpipe_flag) + { +#if defined (JOB_CONTROL) + if (INVALID_JOB (lastpipe_jid) == 0) + { + append_process (savestring (the_printed_command_except_trap), dollar_dollar_pid, exec_result, lastpipe_jid); + lstdin = wait_for (lastpid); + } + else + lstdin = wait_for_single_pid (lastpid, 0); /* checks bgpids list */ +#else + lstdin = wait_for (lastpid); +#endif + +#if defined (JOB_CONTROL) + /* If wait_for removes the job from the jobs table, use result of last + command as pipeline's exit status as usual. The jobs list can get + frozen and unfrozen at inconvenient times if there are multiple pipelines + running simultaneously. */ + if (INVALID_JOB (lastpipe_jid) == 0) + exec_result = job_exit_status (lastpipe_jid); + else if (pipefail_opt) + exec_result = exec_result | lstdin; /* XXX */ + /* otherwise we use exec_result */ +#endif + + set_jobs_list_frozen (old_frozen); + } + + discard_unwind_frame ("lastpipe-exec"); + + return (exec_result); +} + +static int +execute_connection (command, asynchronous, pipe_in, pipe_out, fds_to_close) + COMMAND *command; + int asynchronous, pipe_in, pipe_out; + struct fd_bitmap *fds_to_close; +{ + COMMAND *tc, *second; + int ignore_return, exec_result, was_error_trap, invert; + volatile int save_line_number; + + ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0; + + switch (command->value.Connection->connector) + { + /* Do the first command asynchronously. */ + case '&': + tc = command->value.Connection->first; + if (tc == 0) + return (EXECUTION_SUCCESS); + + if (ignore_return) + tc->flags |= CMD_IGNORE_RETURN; + tc->flags |= CMD_AMPERSAND; + + /* If this shell was compiled without job control support, + if we are currently in a subshell via `( xxx )', or if job + control is not active then the standard input for an + asynchronous command is forced to /dev/null. */ +#if defined (JOB_CONTROL) + if ((subshell_environment || !job_control) && !stdin_redir) +#else + if (!stdin_redir) +#endif /* JOB_CONTROL */ + tc->flags |= CMD_STDIN_REDIR; + + exec_result = execute_command_internal (tc, 1, pipe_in, pipe_out, fds_to_close); + QUIT; + + if (tc->flags & CMD_STDIN_REDIR) + tc->flags &= ~CMD_STDIN_REDIR; + + second = command->value.Connection->second; + if (second) + { + if (ignore_return) + second->flags |= CMD_IGNORE_RETURN; + + exec_result = execute_command_internal (second, asynchronous, pipe_in, pipe_out, fds_to_close); + } + + break; + + /* Just call execute command on both sides. */ + case ';': + if (ignore_return) + { + if (command->value.Connection->first) + command->value.Connection->first->flags |= CMD_IGNORE_RETURN; + if (command->value.Connection->second) + command->value.Connection->second->flags |= CMD_IGNORE_RETURN; + } + executing_list++; + QUIT; + execute_command (command->value.Connection->first); + QUIT; + exec_result = execute_command_internal (command->value.Connection->second, + asynchronous, pipe_in, pipe_out, + fds_to_close); + executing_list--; + break; + + case '|': + was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0; + invert = (command->flags & CMD_INVERT_RETURN) != 0; + ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0; + + line_number_for_err_trap = line_number; /* XXX - save value? */ + exec_result = execute_pipeline (command, asynchronous, pipe_in, pipe_out, fds_to_close); + + if (asynchronous) + { + exec_result = EXECUTION_SUCCESS; + invert = 0; + } + + if (was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + save_line_number = line_number; + line_number = line_number_for_err_trap; + run_error_trap (); + line_number = save_line_number; + } + + if (ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS) + { + last_command_exit_value = exec_result; + run_pending_traps (); + jump_to_top_level (ERREXIT); + } + + break; + + case AND_AND: + case OR_OR: + if (asynchronous) + { + /* If we have something like `a && b &' or `a || b &', run the + && or || stuff in a subshell. Force a subshell and just call + execute_command_internal again. Leave asynchronous on + so that we get a report from the parent shell about the + background job. */ + command->flags |= CMD_FORCE_SUBSHELL; + exec_result = execute_command_internal (command, 1, pipe_in, pipe_out, fds_to_close); + break; + } + + /* Execute the first command. If the result of that is successful + and the connector is AND_AND, or the result is not successful + and the connector is OR_OR, then execute the second command, + otherwise return. */ + + executing_list++; + if (command->value.Connection->first) + command->value.Connection->first->flags |= CMD_IGNORE_RETURN; + + exec_result = execute_command (command->value.Connection->first); + QUIT; + if (((command->value.Connection->connector == AND_AND) && + (exec_result == EXECUTION_SUCCESS)) || + ((command->value.Connection->connector == OR_OR) && + (exec_result != EXECUTION_SUCCESS))) + { + second = command->value.Connection->second; + if (ignore_return && second) + second->flags |= CMD_IGNORE_RETURN; + + exec_result = execute_command (second); + } + executing_list--; + break; + + default: + command_error ("execute_connection", CMDERR_BADCONN, command->value.Connection->connector, 0); + jump_to_top_level (DISCARD); + exec_result = EXECUTION_FAILURE; + } + + return exec_result; +} + +/* The test used to be only for interactive_shell, but we don't want to report + job status when the shell is not interactive or when job control isn't + enabled. */ +#define REAP() \ + do \ + { \ + if (job_control == 0 || interactive_shell == 0) \ + reap_dead_jobs (); \ + } \ + while (0) + +/* Execute a FOR command. The syntax is: FOR word_desc IN word_list; + DO command; DONE */ +static int +execute_for_command (for_command) + FOR_COM *for_command; +{ + register WORD_LIST *releaser, *list; + SHELL_VAR *v; + char *identifier; + int retval, save_line_number; +#if 0 + SHELL_VAR *old_value = (SHELL_VAR *)NULL; /* Remember the old value of x. */ +#endif + + save_line_number = line_number; + if (check_identifier (for_command->name, 1) == 0) + { + if (posixly_correct && interactive_shell == 0) + { + last_command_exit_value = EX_BADUSAGE; + jump_to_top_level (ERREXIT); + } + return (EXECUTION_FAILURE); + } + + loop_level++; + identifier = for_command->name->word; + + line_number = for_command->line; /* for expansion error messages */ + list = releaser = expand_words_no_vars (for_command->map_list); + + begin_unwind_frame ("for"); + add_unwind_protect (dispose_words, releaser); + +#if 0 + if (lexical_scoping) + { + old_value = copy_variable (find_variable (identifier)); + if (old_value) + add_unwind_protect (dispose_variable, old_value); + } +#endif + + if (for_command->flags & CMD_IGNORE_RETURN) + for_command->action->flags |= CMD_IGNORE_RETURN; + + for (retval = EXECUTION_SUCCESS; list; list = list->next) + { + QUIT; + + line_number = for_command->line; + + /* Remember what this command looks like, for debugger. */ + command_string_index = 0; + print_for_command_head (for_command); + + if (echo_command_at_execute) + xtrace_print_for_command_head (for_command); + + /* Save this command unless it's a trap command and we're not running + a debug trap. */ + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + retval = run_debug_trap (); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode && retval != EXECUTION_SUCCESS) + continue; +#endif + + this_command_name = (char *)NULL; + /* XXX - special ksh93 for command index variable handling */ + v = find_variable_last_nameref (identifier, 1); + if (v && nameref_p (v)) + { + if (valid_nameref_value (list->word->word, 1) == 0) + { + sh_invalidid (list->word->word); + v = 0; + } + else if (readonly_p (v)) + err_readonly (name_cell (v)); + else + v = bind_variable_value (v, list->word->word, ASS_NAMEREF); + } + else + v = bind_variable (identifier, list->word->word, 0); + + if (v == 0 || readonly_p (v) || noassign_p (v)) + { + line_number = save_line_number; + if (v && readonly_p (v) && interactive_shell == 0 && posixly_correct) + { + last_command_exit_value = EXECUTION_FAILURE; + jump_to_top_level (FORCE_EOF); + } + else + { + dispose_words (releaser); + discard_unwind_frame ("for"); + loop_level--; + return (EXECUTION_FAILURE); + } + } + + if (ifsname (identifier)) + setifs (v); + + retval = execute_command (for_command->action); + REAP (); + QUIT; + + if (breaking) + { + breaking--; + break; + } + + if (continuing) + { + continuing--; + if (continuing) + break; + } + } + + loop_level--; + line_number = save_line_number; + +#if 0 + if (lexical_scoping) + { + if (!old_value) + unbind_variable (identifier); + else + { + SHELL_VAR *new_value; + + new_value = bind_variable (identifier, value_cell (old_value), 0); + new_value->attributes = old_value->attributes; + dispose_variable (old_value); + } + } +#endif + + dispose_words (releaser); + discard_unwind_frame ("for"); + return (retval); +} + +#if defined (ARITH_FOR_COMMAND) +/* Execute an arithmetic for command. The syntax is + + for (( init ; step ; test )) + do + body + done + + The execution should be exactly equivalent to + + eval \(\( init \)\) + while eval \(\( test \)\) ; do + body; + eval \(\( step \)\) + done +*/ +static intmax_t +eval_arith_for_expr (l, okp) + WORD_LIST *l; + int *okp; +{ + WORD_LIST *new; + intmax_t expresult; + int r; + + new = expand_words_no_vars (l); + if (new) + { + if (echo_command_at_execute) + xtrace_print_arith_cmd (new); + this_command_name = "(("; /* )) for expression error messages */ + + command_string_index = 0; + print_arith_command (new); + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + r = run_debug_trap (); + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ +#if defined (DEBUGGER) + if (debugging_mode == 0 || r == EXECUTION_SUCCESS) + expresult = evalexp (new->word->word, EXP_EXPANDED, okp); + else + { + expresult = 0; + if (okp) + *okp = 1; + } +#else + expresult = evalexp (new->word->word, EXP_EXPANDED, okp); +#endif + dispose_words (new); + } + else + { + expresult = 0; + if (okp) + *okp = 1; + } + return (expresult); +} + +static int +execute_arith_for_command (arith_for_command) + ARITH_FOR_COM *arith_for_command; +{ + intmax_t expresult; + int expok, body_status, arith_lineno, save_lineno; + + body_status = EXECUTION_SUCCESS; + loop_level++; + save_lineno = line_number; + + if (arith_for_command->flags & CMD_IGNORE_RETURN) + arith_for_command->action->flags |= CMD_IGNORE_RETURN; + + this_command_name = "(("; /* )) for expression error messages */ + + /* save the starting line number of the command so we can reset + line_number before executing each expression -- for $LINENO + and the DEBUG trap. */ + line_number = arith_lineno = arith_for_command->line; + if (variable_context && interactive_shell && sourcelevel == 0) + { + /* line numbers in a function start at 1 */ + line_number -= function_line_number - 1; + if (line_number <= 0) + line_number = 1; + } + + /* Evaluate the initialization expression. */ + expresult = eval_arith_for_expr (arith_for_command->init, &expok); + if (expok == 0) + { + line_number = save_lineno; + return (EXECUTION_FAILURE); + } + + while (1) + { + /* Evaluate the test expression. */ + line_number = arith_lineno; + expresult = eval_arith_for_expr (arith_for_command->test, &expok); + line_number = save_lineno; + + if (expok == 0) + { + body_status = EXECUTION_FAILURE; + break; + } + REAP (); + if (expresult == 0) + break; + + /* Execute the body of the arithmetic for command. */ + QUIT; + body_status = execute_command (arith_for_command->action); + QUIT; + + /* Handle any `break' or `continue' commands executed by the body. */ + if (breaking) + { + breaking--; + break; + } + + if (continuing) + { + continuing--; + if (continuing) + break; + } + + /* Evaluate the step expression. */ + line_number = arith_lineno; + expresult = eval_arith_for_expr (arith_for_command->step, &expok); + line_number = save_lineno; + + if (expok == 0) + { + body_status = EXECUTION_FAILURE; + break; + } + } + + loop_level--; + line_number = save_lineno; + + return (body_status); +} +#endif + +#if defined (SELECT_COMMAND) +static int LINES, COLS, tabsize; + +#define RP_SPACE ") " +#define RP_SPACE_LEN 2 + +/* XXX - does not handle numbers > 1000000 at all. */ +#define NUMBER_LEN(s) \ +((s < 10) ? 1 \ + : ((s < 100) ? 2 \ + : ((s < 1000) ? 3 \ + : ((s < 10000) ? 4 \ + : ((s < 100000) ? 5 \ + : 6))))) + +static int +displen (s) + const char *s; +{ +#if defined (HANDLE_MULTIBYTE) + wchar_t *wcstr; + size_t slen; + int wclen; + + wcstr = 0; + slen = mbstowcs (wcstr, s, 0); + if (slen == -1) + slen = 0; + wcstr = (wchar_t *)xmalloc (sizeof (wchar_t) * (slen + 1)); + mbstowcs (wcstr, s, slen + 1); + wclen = wcswidth (wcstr, slen); + free (wcstr); + return (wclen < 0 ? STRLEN(s) : wclen); +#else + return (STRLEN (s)); +#endif +} + +static int +print_index_and_element (len, ind, list) + int len, ind; + WORD_LIST *list; +{ + register WORD_LIST *l; + register int i; + + if (list == 0) + return (0); + for (i = ind, l = list; l && --i; l = l->next) + ; + if (l == 0) /* don't think this can happen */ + return (0); + fprintf (stderr, "%*d%s%s", len, ind, RP_SPACE, l->word->word); + return (displen (l->word->word)); +} + +static void +indent (from, to) + int from, to; +{ + while (from < to) + { + if ((to / tabsize) > (from / tabsize)) + { + putc ('\t', stderr); + from += tabsize - from % tabsize; + } + else + { + putc (' ', stderr); + from++; + } + } +} + +static void +print_select_list (list, list_len, max_elem_len, indices_len) + WORD_LIST *list; + int list_len, max_elem_len, indices_len; +{ + int ind, row, elem_len, pos, cols, rows; + int first_column_indices_len, other_indices_len; + + if (list == 0) + { + putc ('\n', stderr); + return; + } + + cols = max_elem_len ? COLS / max_elem_len : 1; + if (cols == 0) + cols = 1; + rows = list_len ? list_len / cols + (list_len % cols != 0) : 1; + cols = list_len ? list_len / rows + (list_len % rows != 0) : 1; + + if (rows == 1) + { + rows = cols; + cols = 1; + } + + first_column_indices_len = NUMBER_LEN (rows); + other_indices_len = indices_len; + + for (row = 0; row < rows; row++) + { + ind = row; + pos = 0; + while (1) + { + indices_len = (pos == 0) ? first_column_indices_len : other_indices_len; + elem_len = print_index_and_element (indices_len, ind + 1, list); + elem_len += indices_len + RP_SPACE_LEN; + ind += rows; + if (ind >= list_len) + break; + indent (pos + elem_len, pos + max_elem_len); + pos += max_elem_len; + } + putc ('\n', stderr); + } +} + +/* Print the elements of LIST, one per line, preceded by an index from 1 to + LIST_LEN. Then display PROMPT and wait for the user to enter a number. + If the number is between 1 and LIST_LEN, return that selection. If EOF + is read, return a null string. If a blank line is entered, or an invalid + number is entered, the loop is executed again. */ +static char * +select_query (list, list_len, prompt, print_menu) + WORD_LIST *list; + int list_len; + char *prompt; + int print_menu; +{ + int max_elem_len, indices_len, len; + intmax_t reply; + WORD_LIST *l; + char *repl_string, *t; + + COLS = default_columns (); + +#if 0 + t = get_string_value ("TABSIZE"); + tabsize = (t && *t) ? atoi (t) : 8; + if (tabsize <= 0) + tabsize = 8; +#else + tabsize = 8; +#endif + + max_elem_len = 0; + for (l = list; l; l = l->next) + { + len = displen (l->word->word); + if (len > max_elem_len) + max_elem_len = len; + } + indices_len = NUMBER_LEN (list_len); + max_elem_len += indices_len + RP_SPACE_LEN + 2; + + while (1) + { + if (print_menu) + print_select_list (list, list_len, max_elem_len, indices_len); + fprintf (stderr, "%s", prompt); + fflush (stderr); + QUIT; + + if (read_builtin ((WORD_LIST *)NULL) != EXECUTION_SUCCESS) + { + putchar ('\n'); + return ((char *)NULL); + } + repl_string = get_string_value ("REPLY"); + if (repl_string == 0) + return ((char *)NULL); + if (*repl_string == 0) + { + print_menu = 1; + continue; + } + if (legal_number (repl_string, &reply) == 0) + return ""; + if (reply < 1 || reply > list_len) + return ""; + + for (l = list; l && --reply; l = l->next) + ; + return (l->word->word); /* XXX - can't be null? */ + } +} + +/* Execute a SELECT command. The syntax is: + SELECT word IN list DO command_list DONE + Only `break' or `return' in command_list will terminate + the command. */ +static int +execute_select_command (select_command) + SELECT_COM *select_command; +{ + WORD_LIST *releaser, *list; + SHELL_VAR *v; + char *identifier, *ps3_prompt, *selection; + int retval, list_len, show_menu, save_line_number; + + if (check_identifier (select_command->name, 1) == 0) + return (EXECUTION_FAILURE); + + save_line_number = line_number; + line_number = select_command->line; + + command_string_index = 0; + print_select_command_head (select_command); + + if (echo_command_at_execute) + xtrace_print_select_command_head (select_command); + +#if 0 + if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0))) +#else + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) +#endif + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + retval = run_debug_trap (); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode && retval != EXECUTION_SUCCESS) + return (EXECUTION_SUCCESS); +#endif + + loop_level++; + identifier = select_command->name->word; + + /* command and arithmetic substitution, parameter and variable expansion, + word splitting, pathname expansion, and quote removal. */ + list = releaser = expand_words_no_vars (select_command->map_list); + list_len = list_length (list); + if (list == 0 || list_len == 0) + { + if (list) + dispose_words (list); + line_number = save_line_number; + return (EXECUTION_SUCCESS); + } + + begin_unwind_frame ("select"); + add_unwind_protect (dispose_words, releaser); + + if (select_command->flags & CMD_IGNORE_RETURN) + select_command->action->flags |= CMD_IGNORE_RETURN; + + retval = EXECUTION_SUCCESS; + show_menu = 1; + + while (1) + { + line_number = select_command->line; + ps3_prompt = get_string_value ("PS3"); + if (ps3_prompt == 0) + ps3_prompt = "#? "; + + QUIT; + selection = select_query (list, list_len, ps3_prompt, show_menu); + QUIT; + if (selection == 0) + { + /* select_query returns EXECUTION_FAILURE if the read builtin + fails, so we want to return failure in this case. */ + retval = EXECUTION_FAILURE; + break; + } + + v = bind_variable (identifier, selection, 0); + if (v == 0 || readonly_p (v) || noassign_p (v)) + { + if (v && readonly_p (v) && interactive_shell == 0 && posixly_correct) + { + last_command_exit_value = EXECUTION_FAILURE; + jump_to_top_level (FORCE_EOF); + } + else + { + dispose_words (releaser); + discard_unwind_frame ("select"); + loop_level--; + line_number = save_line_number; + return (EXECUTION_FAILURE); + } + } + + retval = execute_command (select_command->action); + + REAP (); + QUIT; + + if (breaking) + { + breaking--; + break; + } + + if (continuing) + { + continuing--; + if (continuing) + break; + } + +#if defined (KSH_COMPATIBLE_SELECT) + show_menu = 0; + selection = get_string_value ("REPLY"); + if (selection && *selection == '\0') + show_menu = 1; +#endif + } + + loop_level--; + line_number = save_line_number; + + dispose_words (releaser); + discard_unwind_frame ("select"); + return (retval); +} +#endif /* SELECT_COMMAND */ + +/* Execute a CASE command. The syntax is: CASE word_desc IN pattern_list ESAC. + The pattern_list is a linked list of pattern clauses; each clause contains + some patterns to compare word_desc against, and an associated command to + execute. */ +static int +execute_case_command (case_command) + CASE_COM *case_command; +{ + register WORD_LIST *list; + WORD_LIST *wlist, *es; + PATTERN_LIST *clauses; + char *word, *pattern; + int retval, match, ignore_return, save_line_number, qflags; + + save_line_number = line_number; + line_number = case_command->line; + + command_string_index = 0; + print_case_command_head (case_command); + + if (echo_command_at_execute) + xtrace_print_case_command_head (case_command); + +#if 0 + if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0))) +#else + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) +#endif + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + retval = run_debug_trap(); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode && retval != EXECUTION_SUCCESS) + { + line_number = save_line_number; + return (EXECUTION_SUCCESS); + } +#endif + + /* Use the same expansions (the ones POSIX specifies) as the patterns; + dequote the resulting string (as POSIX specifies) since the quotes in + patterns are handled specially below. We have to do it in this order + because we're not supposed to perform word splitting. */ + wlist = expand_word_leave_quoted (case_command->word, 0); + if (wlist) + { + char *t; + t = string_list (wlist); + word = dequote_string (t); + free (t); + } + else + word = savestring (""); + dispose_words (wlist); + + retval = EXECUTION_SUCCESS; + ignore_return = case_command->flags & CMD_IGNORE_RETURN; + + begin_unwind_frame ("case"); + add_unwind_protect (xfree, word); + +#define EXIT_CASE() goto exit_case_command + + for (clauses = case_command->clauses; clauses; clauses = clauses->next) + { + QUIT; + for (list = clauses->patterns; list; list = list->next) + { + es = expand_word_leave_quoted (list->word, 0); + + if (es && es->word && es->word->word && *(es->word->word)) + { + /* Convert quoted null strings into empty strings. */ + qflags = QGLOB_CVTNULL; + + /* We left CTLESC in place quoting CTLESC and CTLNUL after the + call to expand_word_leave_quoted; tell quote_string_for_globbing + to remove those here. This works for both unquoted portions of + the word (which call quote_escapes) and quoted portions + (which call quote_string). */ + qflags |= QGLOB_CTLESC; + pattern = quote_string_for_globbing (es->word->word, qflags); + } + else + { + pattern = (char *)xmalloc (1); + pattern[0] = '\0'; + } + + /* Since the pattern does not undergo quote removal (as per + Posix.2, section 3.9.4.3), the strmatch () call must be able + to recognize backslashes as escape characters. */ + match = strmatch (pattern, word, FNMATCH_EXTFLAG|FNMATCH_IGNCASE) != FNM_NOMATCH; + free (pattern); + + dispose_words (es); + + if (match) + { + do + { + if (clauses->action && ignore_return) + clauses->action->flags |= CMD_IGNORE_RETURN; + retval = execute_command (clauses->action); + } + while ((clauses->flags & CASEPAT_FALLTHROUGH) && (clauses = clauses->next)); + if (clauses == 0 || (clauses->flags & CASEPAT_TESTNEXT) == 0) + EXIT_CASE (); + else + break; + } + + QUIT; + } + } + +exit_case_command: + free (word); + discard_unwind_frame ("case"); + line_number = save_line_number; + return (retval); +} + +#define CMD_WHILE 0 +#define CMD_UNTIL 1 + +/* The WHILE command. Syntax: WHILE test DO action; DONE. + Repeatedly execute action while executing test produces + EXECUTION_SUCCESS. */ +static int +execute_while_command (while_command) + WHILE_COM *while_command; +{ + return (execute_while_or_until (while_command, CMD_WHILE)); +} + +/* UNTIL is just like WHILE except that the test result is negated. */ +static int +execute_until_command (while_command) + WHILE_COM *while_command; +{ + return (execute_while_or_until (while_command, CMD_UNTIL)); +} + +/* The body for both while and until. The only difference between the + two is that the test value is treated differently. TYPE is + CMD_WHILE or CMD_UNTIL. The return value for both commands should + be EXECUTION_SUCCESS if no commands in the body are executed, and + the status of the last command executed in the body otherwise. */ +static int +execute_while_or_until (while_command, type) + WHILE_COM *while_command; + int type; +{ + int return_value, body_status; + + body_status = EXECUTION_SUCCESS; + loop_level++; + + while_command->test->flags |= CMD_IGNORE_RETURN; + if (while_command->flags & CMD_IGNORE_RETURN) + while_command->action->flags |= CMD_IGNORE_RETURN; + + while (1) + { + return_value = execute_command (while_command->test); + REAP (); + + /* Need to handle `break' in the test when we would break out of the + loop. The job control code will set `breaking' to loop_level + when a job in a loop is stopped with SIGTSTP. If the stopped job + is in the loop test, `breaking' will not be reset unless we do + this, and the shell will cease to execute commands. The same holds + true for `continue'. */ + if (type == CMD_WHILE && return_value != EXECUTION_SUCCESS) + { + if (breaking) + breaking--; + if (continuing) + continuing--; + break; + } + if (type == CMD_UNTIL && return_value == EXECUTION_SUCCESS) + { + if (breaking) + breaking--; + if (continuing) + continuing--; + break; + } + + QUIT; + body_status = execute_command (while_command->action); + QUIT; + + if (breaking) + { + breaking--; + break; + } + + if (continuing) + { + continuing--; + if (continuing) + break; + } + } + loop_level--; + + return (body_status); +} + +/* IF test THEN command [ELSE command]. + IF also allows ELIF in the place of ELSE IF, but + the parser makes *that* stupidity transparent. */ +static int +execute_if_command (if_command) + IF_COM *if_command; +{ + int return_value, save_line_number; + + save_line_number = line_number; + if_command->test->flags |= CMD_IGNORE_RETURN; + return_value = execute_command (if_command->test); + line_number = save_line_number; + + if (return_value == EXECUTION_SUCCESS) + { + QUIT; + + if (if_command->true_case && (if_command->flags & CMD_IGNORE_RETURN)) + if_command->true_case->flags |= CMD_IGNORE_RETURN; + + return (execute_command (if_command->true_case)); + } + else + { + QUIT; + + if (if_command->false_case && (if_command->flags & CMD_IGNORE_RETURN)) + if_command->false_case->flags |= CMD_IGNORE_RETURN; + + return (execute_command (if_command->false_case)); + } +} + +#if defined (DPAREN_ARITHMETIC) +static int +execute_arith_command (arith_command) + ARITH_COM *arith_command; +{ + int expok, save_line_number, retval; + intmax_t expresult; + WORD_LIST *new; + char *exp; + + expresult = 0; + + save_line_number = line_number; + this_command_name = "(("; /* )) */ + line_number_for_err_trap = line_number = arith_command->line; + /* If we're in a function, update the line number information. */ + if (variable_context && interactive_shell && sourcelevel == 0) + { + /* line numbers in a function start at 1 */ + line_number -= function_line_number - 1; + if (line_number <= 0) + line_number = 1; + } + + command_string_index = 0; + print_arith_command (arith_command->exp); + + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + /* Run the debug trap before each arithmetic command, but do it after we + update the line number information and before we expand the various + words in the expression. */ + retval = run_debug_trap (); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode && retval != EXECUTION_SUCCESS) + { + line_number = save_line_number; + return (EXECUTION_SUCCESS); + } +#endif + + new = expand_words_no_vars (arith_command->exp); + + /* If we're tracing, make a new word list with `((' at the front and `))' + at the back and print it. */ + if (echo_command_at_execute) + xtrace_print_arith_cmd (new); + + if (new) + { + exp = new->next ? string_list (new) : new->word->word; + expresult = evalexp (exp, EXP_EXPANDED, &expok); + line_number = save_line_number; + if (exp != new->word->word) + free (exp); + dispose_words (new); + } + else + { + expresult = 0; + expok = 1; + } + + if (expok == 0) + return (EXECUTION_FAILURE); + + return (expresult == 0 ? EXECUTION_FAILURE : EXECUTION_SUCCESS); +} +#endif /* DPAREN_ARITHMETIC */ + +#if defined (COND_COMMAND) + +static char * const nullstr = ""; + +/* XXX - can COND ever be NULL when this is called? */ +static int +execute_cond_node (cond) + COND_COM *cond; +{ + int result, invert, patmatch, rmatch, mflags, ignore; + char *arg1, *arg2; +#if 0 + char *t1, *t2; +#endif + + invert = (cond->flags & CMD_INVERT_RETURN); + ignore = (cond->flags & CMD_IGNORE_RETURN); + if (ignore) + { + if (cond->left) + cond->left->flags |= CMD_IGNORE_RETURN; + if (cond->right) + cond->right->flags |= CMD_IGNORE_RETURN; + } + + if (cond->type == COND_EXPR) + result = execute_cond_node (cond->left); + else if (cond->type == COND_OR) + { + result = execute_cond_node (cond->left); + if (result != EXECUTION_SUCCESS) + result = execute_cond_node (cond->right); + } + else if (cond->type == COND_AND) + { + result = execute_cond_node (cond->left); + if (result == EXECUTION_SUCCESS) + result = execute_cond_node (cond->right); + } + else if (cond->type == COND_UNARY) + { + if (ignore) + comsub_ignore_return++; + arg1 = cond_expand_word (cond->left->op, 0); + if (ignore) + comsub_ignore_return--; + if (arg1 == 0) + arg1 = nullstr; + if (echo_command_at_execute) + xtrace_print_cond_term (cond->type, invert, cond->op, arg1, (char *)NULL); + result = unary_test (cond->op->word, arg1) ? EXECUTION_SUCCESS : EXECUTION_FAILURE; + if (arg1 != nullstr) + free (arg1); + } + else if (cond->type == COND_BINARY) + { + rmatch = 0; + patmatch = (((cond->op->word[1] == '=') && (cond->op->word[2] == '\0') && + (cond->op->word[0] == '!' || cond->op->word[0] == '=')) || + (cond->op->word[0] == '=' && cond->op->word[1] == '\0')); +#if defined (COND_REGEXP) + rmatch = (cond->op->word[0] == '=' && cond->op->word[1] == '~' && + cond->op->word[2] == '\0'); +#endif + + if (ignore) + comsub_ignore_return++; + arg1 = cond_expand_word (cond->left->op, 0); + if (ignore) + comsub_ignore_return--; + if (arg1 == 0) + arg1 = nullstr; + if (ignore) + comsub_ignore_return++; + arg2 = cond_expand_word (cond->right->op, + (rmatch && shell_compatibility_level > 31) ? 2 : (patmatch ? 1 : 0)); + if (ignore) + comsub_ignore_return--; + if (arg2 == 0) + arg2 = nullstr; + + if (echo_command_at_execute) + xtrace_print_cond_term (cond->type, invert, cond->op, arg1, arg2); + +#if defined (COND_REGEXP) + if (rmatch) + { + mflags = SHMAT_PWARN; +#if defined (ARRAY_VARS) + mflags |= SHMAT_SUBEXP; +#endif + +#if 0 + t1 = strescape(arg1); + t2 = strescape(arg2); + itrace("execute_cond_node: sh_regmatch on `%s' and `%s'", t1, t2); + free(t1); + free(t2); +#endif + + result = sh_regmatch (arg1, arg2, mflags); + } + else +#endif /* COND_REGEXP */ + { + int oe; + oe = extended_glob; + extended_glob = 1; + result = binary_test (cond->op->word, arg1, arg2, TEST_PATMATCH|TEST_ARITHEXP|TEST_LOCALE) + ? EXECUTION_SUCCESS + : EXECUTION_FAILURE; + extended_glob = oe; + } + if (arg1 != nullstr) + free (arg1); + if (arg2 != nullstr) + free (arg2); + } + else + { + command_error ("execute_cond_node", CMDERR_BADTYPE, cond->type, 0); + jump_to_top_level (DISCARD); + result = EXECUTION_FAILURE; + } + + if (invert) + result = (result == EXECUTION_SUCCESS) ? EXECUTION_FAILURE : EXECUTION_SUCCESS; + + return result; +} + +static int +execute_cond_command (cond_command) + COND_COM *cond_command; +{ + int retval, save_line_number; + + save_line_number = line_number; + + this_command_name = "[["; + line_number_for_err_trap = line_number = cond_command->line; + /* If we're in a function, update the line number information. */ + if (variable_context && interactive_shell && sourcelevel == 0) + { + /* line numbers in a function start at 1 */ + line_number -= function_line_number - 1; + if (line_number <= 0) + line_number = 1; + } + command_string_index = 0; + print_cond_command (cond_command); + + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = savestring (the_printed_command); + } + + /* Run the debug trap before each conditional command, but do it after we + update the line number information. */ + retval = run_debug_trap (); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode && retval != EXECUTION_SUCCESS) + { + line_number = save_line_number; + return (EXECUTION_SUCCESS); + } +#endif + +#if 0 + debug_print_cond_command (cond_command); +#endif + + last_command_exit_value = retval = execute_cond_node (cond_command); + line_number = save_line_number; + return (retval); +} +#endif /* COND_COMMAND */ + +static void +bind_lastarg (arg) + char *arg; +{ + SHELL_VAR *var; + + if (arg == 0) + arg = ""; + var = bind_variable ("_", arg, 0); + if (var) + VUNSETATTR (var, att_exported); +} + +/* Execute a null command. Fork a subshell if the command uses pipes or is + to be run asynchronously. This handles all the side effects that are + supposed to take place. */ +static int +execute_null_command (redirects, pipe_in, pipe_out, async) + REDIRECT *redirects; + int pipe_in, pipe_out, async; +{ + int r; + int forcefork; + REDIRECT *rd; + + for (forcefork = 0, rd = redirects; rd; rd = rd->next) + { + forcefork += rd->rflags & REDIR_VARASSIGN; + /* Safety */ + forcefork += (rd->redirector.dest == 0 || fd_is_bash_input (rd->redirector.dest)) && (INPUT_REDIRECT (rd->instruction) || TRANSLATE_REDIRECT (rd->instruction) || rd->instruction == r_close_this); + } + + if (forcefork || pipe_in != NO_PIPE || pipe_out != NO_PIPE || async) + { + /* We have a null command, but we really want a subshell to take + care of it. Just fork, do piping and redirections, and exit. */ + if (make_child ((char *)NULL, async) == 0) + { + /* Cancel traps, in trap.c. */ + restore_original_signals (); /* XXX */ + + do_piping (pipe_in, pipe_out); + +#if defined (COPROCESS_SUPPORT) + coproc_closeall (); +#endif + + interactive = 0; /* XXX */ + + subshell_environment = 0; + if (async) + subshell_environment |= SUBSHELL_ASYNC; + if (pipe_in != NO_PIPE || pipe_out != NO_PIPE) + subshell_environment |= SUBSHELL_PIPE; + + if (do_redirections (redirects, RX_ACTIVE) == 0) + exit (EXECUTION_SUCCESS); + else + exit (EXECUTION_FAILURE); + } + else + { + close_pipes (pipe_in, pipe_out); +#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) + if (pipe_out == NO_PIPE) + unlink_fifo_list (); +#endif + return (EXECUTION_SUCCESS); + } + } + else + { + /* Even if there aren't any command names, pretend to do the + redirections that are specified. The user expects the side + effects to take place. If the redirections fail, then return + failure. Otherwise, if a command substitution took place while + expanding the command or a redirection, return the value of that + substitution. Otherwise, return EXECUTION_SUCCESS. */ + + r = do_redirections (redirects, RX_ACTIVE|RX_UNDOABLE); + cleanup_redirects (redirection_undo_list); + redirection_undo_list = (REDIRECT *)NULL; + + if (r != 0) + return (EXECUTION_FAILURE); + else if (last_command_subst_pid != NO_PID) + return (last_command_exit_value); + else + return (EXECUTION_SUCCESS); + } +} + +/* This is a hack to suppress word splitting for assignment statements + given as arguments to builtins with the ASSIGNMENT_BUILTIN flag set. */ +static void +fix_assignment_words (words) + WORD_LIST *words; +{ + WORD_LIST *w, *wcmd; + struct builtin *b; + int assoc, global, array, integer; + + if (words == 0) + return; + + b = 0; + assoc = global = array = integer = 0; + + /* Skip over assignment statements preceding a command name */ + wcmd = words; + for (wcmd = words; wcmd; wcmd = wcmd->next) + if ((wcmd->word->flags & W_ASSIGNMENT) == 0) + break; + /* Posix (post-2008) says that `command' doesn't change whether + or not the builtin it shadows is a `declaration command', even + though it removes other special builtin properties. In Posix + mode, we skip over one or more instances of `command' and + deal with the next word as the assignment builtin. */ + while (posixly_correct && wcmd && wcmd->word && wcmd->word->word && STREQ (wcmd->word->word, "command")) + wcmd = wcmd->next; + + for (w = wcmd; w; w = w->next) + if (w->word->flags & W_ASSIGNMENT) + { + /* Lazy builtin lookup, only do it if we find an assignment */ + if (b == 0) + { + b = builtin_address_internal (wcmd->word->word, 0); + if (b == 0 || (b->flags & ASSIGNMENT_BUILTIN) == 0) + return; + else if (b && (b->flags & ASSIGNMENT_BUILTIN)) + wcmd->word->flags |= W_ASSNBLTIN; + } + w->word->flags |= (W_NOSPLIT|W_NOGLOB|W_TILDEEXP|W_ASSIGNARG); +#if defined (ARRAY_VARS) + if (assoc) + w->word->flags |= W_ASSIGNASSOC; + if (array) + w->word->flags |= W_ASSIGNARRAY; +#endif + if (global) + w->word->flags |= W_ASSNGLOBAL; + + /* If we have an assignment builtin that does not create local variables, + make sure we create global variables even if we internally call + `declare'. The CHKLOCAL flag means to set attributes or values on + an existing local variable, if there is one. */ + if (b && ((b->flags & (ASSIGNMENT_BUILTIN|LOCALVAR_BUILTIN)) == ASSIGNMENT_BUILTIN)) + w->word->flags |= W_ASSNGLOBAL|W_CHKLOCAL; +#if 0 + else if (b && (b->flags & ASSIGNMENT_BUILTIN) && (b->flags & LOCALVAR_BUILTIN)) + w->word->flags |= W_CHKLOCAL; +#endif + } +#if defined (ARRAY_VARS) + /* Note that we saw an associative array option to a builtin that takes + assignment statements. This is a bit of a kludge. */ + else if (w->word->word[0] == '-' && (strpbrk (w->word->word+1, "Aag") != 0)) +#else + else if (w->word->word[0] == '-' && strchr (w->word->word+1, 'g')) +#endif + { + if (b == 0) + { + b = builtin_address_internal (wcmd->word->word, 0); + if (b == 0 || (b->flags & ASSIGNMENT_BUILTIN) == 0) + return; + else if (b && (b->flags & ASSIGNMENT_BUILTIN)) + wcmd->word->flags |= W_ASSNBLTIN; + } + if ((wcmd->word->flags & W_ASSNBLTIN) && strchr (w->word->word+1, 'A')) + assoc = 1; + else if ((wcmd->word->flags & W_ASSNBLTIN) && strchr (w->word->word+1, 'a')) + array = 1; + if ((wcmd->word->flags & W_ASSNBLTIN) && strchr (w->word->word+1, 'g')) + global = 1; + } +} + +/* Return 1 if the file found by searching $PATH for PATHNAME, defaulting + to PATHNAME, is a directory. Used by the autocd code below. */ +static int +is_dirname (pathname) + char *pathname; +{ + char *temp; + int ret; + + temp = search_for_command (pathname, 0); + ret = temp ? file_isdir (temp) : file_isdir (pathname); + free (temp); + return ret; +} + +/* The meaty part of all the executions. We have to start hacking the + real execution of commands here. Fork a process, set things up, + execute the command. */ +static int +execute_simple_command (simple_command, pipe_in, pipe_out, async, fds_to_close) + SIMPLE_COM *simple_command; + int pipe_in, pipe_out, async; + struct fd_bitmap *fds_to_close; +{ + WORD_LIST *words, *lastword; + char *command_line, *lastarg, *temp; + int first_word_quoted, result, builtin_is_special, already_forked, dofork; + pid_t old_last_async_pid; + sh_builtin_func_t *builtin; + SHELL_VAR *func; + volatile int old_builtin, old_command_builtin; + + result = EXECUTION_SUCCESS; + special_builtin_failed = builtin_is_special = 0; + command_line = (char *)0; + + QUIT; + + /* If we're in a function, update the line number information. */ + if (variable_context && interactive_shell && sourcelevel == 0) + { + /* line numbers in a function start at 1 */ + line_number -= function_line_number - 1; + if (line_number <= 0) + line_number = 1; + } + + /* Remember what this command line looks like at invocation. */ + command_string_index = 0; + print_simple_command (simple_command); + +#if 0 + if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0))) +#else + if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0) +#endif + { + FREE (the_printed_command_except_trap); + the_printed_command_except_trap = the_printed_command ? savestring (the_printed_command) : (char *)0; + } + + /* Run the debug trap before each simple command, but do it after we + update the line number information. */ + result = run_debug_trap (); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode && result != EXECUTION_SUCCESS) + return (EXECUTION_SUCCESS); +#endif + + first_word_quoted = + simple_command->words ? (simple_command->words->word->flags & W_QUOTED) : 0; + + last_command_subst_pid = NO_PID; + old_last_async_pid = last_asynchronous_pid; + + already_forked = 0; + + /* If we're in a pipeline or run in the background, set DOFORK so we + make the child early, before word expansion. This keeps assignment + statements from affecting the parent shell's environment when they + should not. */ + dofork = pipe_in != NO_PIPE || pipe_out != NO_PIPE || async; + + /* Something like `%2 &' should restart job 2 in the background, not cause + the shell to fork here. */ + if (dofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE && + simple_command->words && simple_command->words->word && + simple_command->words->word->word && + (simple_command->words->word->word[0] == '%')) + dofork = 0; + + if (dofork) + { + char *p; + + /* Do this now, because execute_disk_command will do it anyway in the + vast majority of cases. */ + maybe_make_export_env (); + + /* Don't let a DEBUG trap overwrite the command string to be saved with + the process/job associated with this child. */ + if (make_child (p = savestring (the_printed_command_except_trap), async) == 0) + { + already_forked = 1; + simple_command->flags |= CMD_NO_FORK; + + subshell_environment = SUBSHELL_FORK; /* XXX */ + if (pipe_in != NO_PIPE || pipe_out != NO_PIPE) + subshell_environment |= SUBSHELL_PIPE; + if (async) + subshell_environment |= SUBSHELL_ASYNC; + + /* We need to do this before piping to handle some really + pathological cases where one of the pipe file descriptors + is < 2. */ + if (fds_to_close) + close_fd_bitmap (fds_to_close); + + /* If we fork because of an input pipe, note input pipe for later to + inhibit async commands from redirecting stdin from /dev/null */ + stdin_redir |= pipe_in != NO_PIPE; + + do_piping (pipe_in, pipe_out); + pipe_in = pipe_out = NO_PIPE; +#if defined (COPROCESS_SUPPORT) + coproc_closeall (); +#endif + + last_asynchronous_pid = old_last_async_pid; + + CHECK_SIGTERM; + + if (async) + subshell_level++; /* not for pipes yet */ + +#if defined (JOB_CONTROL) + FREE (p); /* child doesn't use pointer */ +#endif + } + else + { + /* Don't let simple commands that aren't the last command in a + pipeline change $? for the rest of the pipeline (or at all). */ + if (pipe_out != NO_PIPE) + result = last_command_exit_value; + close_pipes (pipe_in, pipe_out); +#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) +#if 0 + /* Close /dev/fd file descriptors in the parent after forking the + last child in a (possibly one-element) pipeline. Defer this + until any running shell function completes. */ + if (pipe_out == NO_PIPE && variable_context == 0) /* XXX */ + unlink_fifo_list (); /* XXX */ +#endif +#endif + command_line = (char *)NULL; /* don't free this. */ +#if 0 + bind_lastarg ((char *)NULL); +#endif + return (result); + } + } + + QUIT; /* XXX */ + + /* If we are re-running this as the result of executing the `command' + builtin, do not expand the command words a second time. */ + if ((simple_command->flags & CMD_INHIBIT_EXPANSION) == 0) + { + current_fds_to_close = fds_to_close; + fix_assignment_words (simple_command->words); + /* Pass the ignore return flag down to command substitutions */ + if (simple_command->flags & CMD_IGNORE_RETURN) /* XXX */ + comsub_ignore_return++; + words = expand_words (simple_command->words); + if (simple_command->flags & CMD_IGNORE_RETURN) + comsub_ignore_return--; + current_fds_to_close = (struct fd_bitmap *)NULL; + } + else + words = copy_word_list (simple_command->words); + + /* It is possible for WORDS not to have anything left in it. + Perhaps all the words consisted of `$foo', and there was + no variable `$foo'. */ + if (words == 0) + { + this_command_name = 0; + result = execute_null_command (simple_command->redirects, + pipe_in, pipe_out, + already_forked ? 0 : async); + if (already_forked) + sh_exit (result); + else + { + bind_lastarg ((char *)NULL); + set_pipestatus_from_exit (result); + return (result); + } + } + + lastarg = (char *)NULL; + + begin_unwind_frame ("simple-command"); + + if (echo_command_at_execute) + xtrace_print_word_list (words, 1); + + builtin = (sh_builtin_func_t *)NULL; + func = (SHELL_VAR *)NULL; + if ((simple_command->flags & CMD_NO_FUNCTIONS) == 0) + { + /* Posix.2 says special builtins are found before functions. We + don't set builtin_is_special anywhere other than here, because + this path is followed only when the `command' builtin is *not* + being used, and we don't want to exit the shell if a special + builtin executed with `command builtin' fails. `command' is not + a special builtin. */ + if (posixly_correct) + { + builtin = find_special_builtin (words->word->word); + if (builtin) + builtin_is_special = 1; + } + if (builtin == 0) + func = find_function (words->word->word); + } + + /* In POSIX mode, assignment errors in the temporary environment cause a + non-interactive shell to exit. */ + if (posixly_correct && builtin_is_special && interactive_shell == 0 && tempenv_assign_error) + { + last_command_exit_value = EXECUTION_FAILURE; + jump_to_top_level (ERREXIT); + } + tempenv_assign_error = 0; /* don't care about this any more */ + + add_unwind_protect (dispose_words, words); + QUIT; + + /* Bind the last word in this command to "$_" after execution. */ + for (lastword = words; lastword->next; lastword = lastword->next) + ; + lastarg = lastword->word->word; + +#if defined (JOB_CONTROL) + /* Is this command a job control related thing? */ + if (words->word->word[0] == '%' && already_forked == 0) + { + this_command_name = async ? "bg" : "fg"; + last_shell_builtin = this_shell_builtin; + this_shell_builtin = builtin_address (this_command_name); + result = (*this_shell_builtin) (words); + goto return_result; + } + + /* One other possibililty. The user may want to resume an existing job. + If they do, find out whether this word is a candidate for a running + job. */ + if (job_control && already_forked == 0 && async == 0 && + !first_word_quoted && + !words->next && + words->word->word[0] && + !simple_command->redirects && + pipe_in == NO_PIPE && + pipe_out == NO_PIPE && + (temp = get_string_value ("auto_resume"))) + { + int job, jflags, started_status; + + jflags = JM_STOPPED|JM_FIRSTMATCH; + if (STREQ (temp, "exact")) + jflags |= JM_EXACT; + else if (STREQ (temp, "substring")) + jflags |= JM_SUBSTRING; + else + jflags |= JM_PREFIX; + job = get_job_by_name (words->word->word, jflags); + if (job != NO_JOB) + { + run_unwind_frame ("simple-command"); + this_command_name = "fg"; + last_shell_builtin = this_shell_builtin; + this_shell_builtin = builtin_address ("fg"); + + started_status = start_job (job, 1); + return ((started_status < 0) ? EXECUTION_FAILURE : started_status); + } + } +#endif /* JOB_CONTROL */ + +run_builtin: + /* Remember the name of this command globally. */ + this_command_name = words->word->word; + + QUIT; + + /* This command could be a shell builtin or a user-defined function. + We have already found special builtins by this time, so we do not + set builtin_is_special. If this is a function or builtin, and we + have pipes, then fork a subshell in here. Otherwise, just execute + the command directly. */ + if (func == 0 && builtin == 0) + builtin = find_shell_builtin (this_command_name); + + last_shell_builtin = this_shell_builtin; + this_shell_builtin = builtin; + + if (builtin || func) + { + if (builtin) + { + old_builtin = executing_builtin; + old_command_builtin = executing_command_builtin; + unwind_protect_int (executing_builtin); /* modified in execute_builtin */ + unwind_protect_int (executing_command_builtin); /* ditto */ + } + if (already_forked) + { + /* reset_terminating_signals (); */ /* XXX */ + /* Reset the signal handlers in the child, but don't free the + trap strings. Set a flag noting that we have to free the + trap strings if we run trap to change a signal disposition. */ + reset_signal_handlers (); + subshell_environment |= SUBSHELL_RESETTRAP; + + if (async) + { + if ((simple_command->flags & CMD_STDIN_REDIR) && + pipe_in == NO_PIPE && + (stdin_redirects (simple_command->redirects) == 0)) + async_redirect_stdin (); + setup_async_signals (); + } + + if (async == 0) + subshell_level++; + execute_subshell_builtin_or_function + (words, simple_command->redirects, builtin, func, + pipe_in, pipe_out, async, fds_to_close, + simple_command->flags); + subshell_level--; + } + else + { + result = execute_builtin_or_function + (words, builtin, func, simple_command->redirects, fds_to_close, + simple_command->flags); + if (builtin) + { + if (result > EX_SHERRBASE) + { + switch (result) + { + case EX_REDIRFAIL: + case EX_BADASSIGN: + case EX_EXPFAIL: + /* These errors cause non-interactive posix mode shells to exit */ + if (posixly_correct && builtin_is_special && interactive_shell == 0) + { + last_command_exit_value = EXECUTION_FAILURE; + jump_to_top_level (ERREXIT); + } + break; + case EX_DISKFALLBACK: + /* XXX - experimental */ + executing_builtin = old_builtin; + executing_command_builtin = old_command_builtin; + builtin = 0; + /* XXX - redirections will have to be performed again */ + goto execute_from_filesystem; + } + result = builtin_status (result); + if (builtin_is_special) + special_builtin_failed = 1; /* XXX - take command builtin into account? */ + } + /* In POSIX mode, if there are assignment statements preceding + a special builtin, they persist after the builtin + completes. */ + if (posixly_correct && builtin_is_special && temporary_env) + merge_temporary_env (); + } + else /* function */ + { + if (result == EX_USAGE) + result = EX_BADUSAGE; + else if (result > EX_SHERRBASE) + result = EXECUTION_FAILURE; + } + + set_pipestatus_from_exit (result); + + goto return_result; + } + } + + if (autocd && interactive && words->word && is_dirname (words->word->word)) + { + words = make_word_list (make_word ("--"), words); + words = make_word_list (make_word ("cd"), words); + xtrace_print_word_list (words, 0); + func = find_function ("cd"); + goto run_builtin; + } + +execute_from_filesystem: + if (command_line == 0) + command_line = savestring (the_printed_command_except_trap ? the_printed_command_except_trap : ""); + +#if defined (PROCESS_SUBSTITUTION) + /* The old code did not test already_forked and only did this if + subshell_environment&SUBSHELL_COMSUB != 0 (comsubs and procsubs). Other + uses of the no-fork optimization left FIFOs in $TMPDIR */ + if (already_forked == 0 && (simple_command->flags & CMD_NO_FORK) && fifos_pending() > 0) + simple_command->flags &= ~CMD_NO_FORK; +#endif + result = execute_disk_command (words, simple_command->redirects, command_line, + pipe_in, pipe_out, async, fds_to_close, + simple_command->flags); + + return_result: + bind_lastarg (lastarg); + FREE (command_line); + dispose_words (words); + if (builtin) + { + executing_builtin = old_builtin; + executing_command_builtin = old_command_builtin; + } + discard_unwind_frame ("simple-command"); + this_command_name = (char *)NULL; /* points to freed memory now */ + return (result); +} + +/* Translate the special builtin exit statuses. We don't really need a + function for this; it's a placeholder for future work. */ +static int +builtin_status (result) + int result; +{ + int r; + + switch (result) + { + case EX_USAGE: + r = EX_BADUSAGE; + break; + case EX_REDIRFAIL: + case EX_BADSYNTAX: + case EX_BADASSIGN: + case EX_EXPFAIL: + r = EXECUTION_FAILURE; + break; + default: + r = EXECUTION_SUCCESS; + break; + } + return (r); +} + +static int +execute_builtin (builtin, words, flags, subshell) + sh_builtin_func_t *builtin; + WORD_LIST *words; + int flags, subshell; +{ + int result, eval_unwind, ignexit_flag; + int isbltinenv, should_keep; + char *error_trap; + + error_trap = 0; + should_keep = 0; + + /* The eval builtin calls parse_and_execute, which does not know about + the setting of flags, and always calls the execution functions with + flags that will exit the shell on an error if -e is set. If the + eval builtin is being called, and we're supposed to ignore the exit + value of the command, we turn the -e flag off ourselves and disable + the ERR trap, then restore them when the command completes. This is + also a problem (as below) for the command and source/. builtins. */ + if (subshell == 0 && (flags & CMD_IGNORE_RETURN) && + (builtin == eval_builtin || builtin == command_builtin || builtin == source_builtin)) + { + begin_unwind_frame ("eval_builtin"); + unwind_protect_int (exit_immediately_on_error); + unwind_protect_int (builtin_ignoring_errexit); + error_trap = TRAP_STRING (ERROR_TRAP); + if (error_trap) + { + error_trap = savestring (error_trap); + add_unwind_protect (xfree, error_trap); + add_unwind_protect (set_error_trap, error_trap); + restore_default_signal (ERROR_TRAP); + } + exit_immediately_on_error = 0; + ignexit_flag = builtin_ignoring_errexit; + builtin_ignoring_errexit = 1; + eval_unwind = 1; + } + else + eval_unwind = 0; + + /* The temporary environment for a builtin is supposed to apply to + all commands executed by that builtin. Currently, this is a + problem only with the `unset', `source' and `eval' builtins. + `mapfile' is a special case because it uses evalstring (same as + eval or source) to run its callbacks. */ + /* SHOULD_KEEP is for the pop_scope call below; it only matters when + posixly_correct is set, but we should propagate the temporary environment + to the enclosing environment only for special builtins. */ + isbltinenv = (builtin == source_builtin || builtin == eval_builtin || builtin == unset_builtin || builtin == mapfile_builtin); + should_keep = isbltinenv && builtin != mapfile_builtin; +#if defined (HISTORY) && defined (READLINE) + if (builtin == fc_builtin || builtin == read_builtin) + { + isbltinenv = 1; + should_keep = 0; + } +#endif + + if (isbltinenv) + { + if (subshell == 0) + begin_unwind_frame ("builtin_env"); + + if (temporary_env) + { + push_scope (VC_BLTNENV, temporary_env); + if (flags & CMD_COMMAND_BUILTIN) + should_keep = 0; + if (subshell == 0) + add_unwind_protect (pop_scope, should_keep ? "1" : 0); + temporary_env = (HASH_TABLE *)NULL; + } + } + + if (subshell == 0 && builtin == eval_builtin) + { + if (evalnest_max > 0 && evalnest >= evalnest_max) + { + internal_error (_("eval: maximum eval nesting level exceeded (%d)"), evalnest); + evalnest = 0; + jump_to_top_level (DISCARD); + } + unwind_protect_int (evalnest); + /* The test for subshell == 0 above doesn't make a difference */ + evalnest++; /* execute_subshell_builtin_or_function sets this to 0 */ + } + else if (subshell == 0 && builtin == source_builtin) + { + if (sourcenest_max > 0 && sourcenest >= sourcenest_max) + { + internal_error (_("%s: maximum source nesting level exceeded (%d)"), this_command_name, sourcenest); + sourcenest = 0; + jump_to_top_level (DISCARD); + } + unwind_protect_int (sourcenest); + /* The test for subshell == 0 above doesn't make a difference */ + sourcenest++; /* execute_subshell_builtin_or_function sets this to 0 */ + } + + /* `return' does a longjmp() back to a saved environment in execute_function. + If a variable assignment list preceded the command, and the shell is + running in POSIX mode, we need to merge that into the shell_variables + table, since `return' is a POSIX special builtin. We don't do this if + it's being run by the `command' builtin, since that's supposed to inhibit + the special builtin properties. */ + if (posixly_correct && subshell == 0 && builtin == return_builtin && (flags & CMD_COMMAND_BUILTIN) == 0 && temporary_env) + { + begin_unwind_frame ("return_temp_env"); + add_unwind_protect (merge_temporary_env, (char *)NULL); + } + + executing_builtin++; + executing_command_builtin |= builtin == command_builtin; + result = ((*builtin) (words->next)); + + /* This shouldn't happen, but in case `return' comes back instead of + longjmp'ing, we need to unwind. */ + if (posixly_correct && subshell == 0 && builtin == return_builtin && temporary_env) + discard_unwind_frame ("return_temp_env"); + + if (subshell == 0 && isbltinenv) + run_unwind_frame ("builtin_env"); + + if (eval_unwind) + { + builtin_ignoring_errexit = ignexit_flag; + exit_immediately_on_error = builtin_ignoring_errexit ? 0 : errexit_flag; + if (error_trap) + { + set_error_trap (error_trap); + free (error_trap); + } + discard_unwind_frame ("eval_builtin"); + } + + return (result); +} + +static void +maybe_restore_getopt_state (gs) + sh_getopt_state_t *gs; +{ + /* If we have a local copy of OPTIND and it's at the right (current) + context, then we restore getopt's internal state. If not, we just + let it go. We know there is a local OPTIND if gs->gs_flags & 1. + This is set below in execute_function() before the context is run. */ + if (gs->gs_flags & 1) + sh_getopt_restore_istate (gs); + else + free (gs); +} + +#if defined (ARRAY_VARS) +void +restore_funcarray_state (fa) + struct func_array_state *fa; +{ + SHELL_VAR *nfv; + ARRAY *funcname_a; + + array_pop (fa->source_a); + array_pop (fa->lineno_a); + + GET_ARRAY_FROM_VAR ("FUNCNAME", nfv, funcname_a); + if (nfv == fa->funcname_v) + array_pop (funcname_a); + + free (fa); +} +#endif + +static int +execute_function (var, words, flags, fds_to_close, async, subshell) + SHELL_VAR *var; + WORD_LIST *words; + int flags; + struct fd_bitmap *fds_to_close; + int async, subshell; +{ + int return_val, result; + COMMAND *tc, *fc, *save_current; + char *debug_trap, *error_trap, *return_trap; +#if defined (ARRAY_VARS) + SHELL_VAR *funcname_v, *bash_source_v, *bash_lineno_v; + ARRAY *funcname_a; + volatile ARRAY *bash_source_a; + volatile ARRAY *bash_lineno_a; + struct func_array_state *fa; +#endif + FUNCTION_DEF *shell_fn; + char *sfile, *t; + sh_getopt_state_t *gs; + SHELL_VAR *gv; + + USE_VAR(fc); + + if (funcnest_max > 0 && funcnest >= funcnest_max) + { + internal_error (_("%s: maximum function nesting level exceeded (%d)"), var->name, funcnest); + funcnest = 0; /* XXX - should we reset it somewhere else? */ + jump_to_top_level (DISCARD); + } + +#if defined (ARRAY_VARS) + GET_ARRAY_FROM_VAR ("FUNCNAME", funcname_v, funcname_a); + GET_ARRAY_FROM_VAR ("BASH_SOURCE", bash_source_v, bash_source_a); + GET_ARRAY_FROM_VAR ("BASH_LINENO", bash_lineno_v, bash_lineno_a); +#endif + + tc = (COMMAND *)copy_command (function_cell (var)); + if (tc && (flags & CMD_IGNORE_RETURN)) + tc->flags |= CMD_IGNORE_RETURN; + + gs = sh_getopt_save_istate (); + if (subshell == 0) + { + begin_unwind_frame ("function_calling"); + /* If the shell is in posix mode, this will push the variables in + the temporary environment to the "current shell environment" (the + global scope), and dispose the temporary env before setting it to + NULL later. This behavior has disappeared from the latest edition + of the standard, so I will eventually remove it from variables.c: + push_var_context. */ + push_context (var->name, subshell, temporary_env); + /* This has to be before the pop_context(), because the unwinding of + local variables may cause the restore of a local declaration of + OPTIND to force a getopts state reset. */ + add_unwind_protect (maybe_restore_getopt_state, gs); + add_unwind_protect (pop_context, (char *)NULL); + unwind_protect_int (line_number); + unwind_protect_int (line_number_for_err_trap); + unwind_protect_int (function_line_number); + unwind_protect_int (return_catch_flag); + unwind_protect_jmp_buf (return_catch); + add_unwind_protect (dispose_command, (char *)tc); + unwind_protect_pointer (this_shell_function); + unwind_protect_int (funcnest); + unwind_protect_int (loop_level); + } + else + push_context (var->name, subshell, temporary_env); /* don't unwind-protect for subshells */ + + temporary_env = (HASH_TABLE *)NULL; + + this_shell_function = var; + make_funcname_visible (1); + + debug_trap = TRAP_STRING(DEBUG_TRAP); + error_trap = TRAP_STRING(ERROR_TRAP); + return_trap = TRAP_STRING(RETURN_TRAP); + + /* The order of the unwind protects for debug_trap, error_trap and + return_trap is important here! unwind-protect commands are run + in reverse order of registration. If this causes problems, take + out the xfree unwind-protect calls and live with the small memory leak. */ + + /* function_trace_mode != 0 means that all functions inherit the DEBUG trap. + if the function has the trace attribute set, it inherits the DEBUG trap */ + if (debug_trap && ((trace_p (var) == 0) && function_trace_mode == 0)) + { + if (subshell == 0) + { + debug_trap = savestring (debug_trap); + add_unwind_protect (xfree, debug_trap); + add_unwind_protect (maybe_set_debug_trap, debug_trap); + } + restore_default_signal (DEBUG_TRAP); + } + + /* error_trace_mode != 0 means that functions inherit the ERR trap. */ + if (error_trap && error_trace_mode == 0) + { + if (subshell == 0) + { + error_trap = savestring (error_trap); + add_unwind_protect (xfree, error_trap); + add_unwind_protect (maybe_set_error_trap, error_trap); + } + restore_default_signal (ERROR_TRAP); + } + + /* Shell functions inherit the RETURN trap if function tracing is on + globally or on individually for this function. */ + if (return_trap && (signal_in_progress (DEBUG_TRAP) || ((trace_p (var) == 0) && function_trace_mode == 0))) + { + if (subshell == 0) + { + return_trap = savestring (return_trap); + add_unwind_protect (xfree, return_trap); + add_unwind_protect (maybe_set_return_trap, return_trap); + } + restore_default_signal (RETURN_TRAP); + } + + funcnest++; +#if defined (ARRAY_VARS) + /* This is quite similar to the code in shell.c and elsewhere. */ + shell_fn = find_function_def (this_shell_function->name); + sfile = shell_fn ? shell_fn->source_file : ""; + array_push ((ARRAY *)funcname_a, this_shell_function->name); + + array_push ((ARRAY *)bash_source_a, sfile); + t = itos (executing_line_number ()); + array_push ((ARRAY *)bash_lineno_a, t); + free (t); +#endif + +#if defined (ARRAY_VARS) + fa = (struct func_array_state *)xmalloc (sizeof (struct func_array_state)); + fa->source_a = (ARRAY *)bash_source_a; + fa->source_v = bash_source_v; + fa->lineno_a = (ARRAY *)bash_lineno_a; + fa->lineno_v = bash_lineno_v; + fa->funcname_a = (ARRAY *)funcname_a; + fa->funcname_v = funcname_v; + if (subshell == 0) + add_unwind_protect (restore_funcarray_state, fa); +#endif + + /* The temporary environment for a function is supposed to apply to + all commands executed within the function body. */ + + /* Initialize BASH_ARGC and BASH_ARGV before we blow away the positional + parameters */ + if (debugging_mode || shell_compatibility_level <= 44) + init_bash_argv (); + + remember_args (words->next, 1); + + /* Update BASH_ARGV and BASH_ARGC */ + if (debugging_mode) + { + push_args (words->next); + if (subshell == 0) + add_unwind_protect (pop_args, 0); + } + + /* Number of the line on which the function body starts. */ + line_number = function_line_number = tc->line; + +#if defined (JOB_CONTROL) + if (subshell) + stop_pipeline (async, (COMMAND *)NULL); +#endif + + if (shell_compatibility_level > 43) + loop_level = 0; + + fc = tc; + + from_return_trap = 0; + + return_catch_flag++; + return_val = setjmp_nosigs (return_catch); + + if (return_val) + { + result = return_catch_value; + /* Run the RETURN trap in the function's context. */ + save_current = currently_executing_command; + if (from_return_trap == 0) + run_return_trap (); + currently_executing_command = save_current; + } + else + { + /* Run the debug trap here so we can trap at the start of a function's + execution rather than the execution of the body's first command. */ + showing_function_line = 1; + save_current = currently_executing_command; + result = run_debug_trap (); +#if defined (DEBUGGER) + /* In debugging mode, if the DEBUG trap returns a non-zero status, we + skip the command. */ + if (debugging_mode == 0 || result == EXECUTION_SUCCESS) + { + showing_function_line = 0; + currently_executing_command = save_current; + result = execute_command_internal (fc, 0, NO_PIPE, NO_PIPE, fds_to_close); + + /* Run the RETURN trap in the function's context */ + save_current = currently_executing_command; + run_return_trap (); + currently_executing_command = save_current; + } +#else + result = execute_command_internal (fc, 0, NO_PIPE, NO_PIPE, fds_to_close); + + save_current = currently_executing_command; + run_return_trap (); + currently_executing_command = save_current; +#endif + showing_function_line = 0; + } + + /* If we have a local copy of OPTIND, note it in the saved getopts state. */ + gv = find_variable ("OPTIND"); + if (gv && gv->context == variable_context) + gs->gs_flags |= 1; + + if (subshell == 0) + run_unwind_frame ("function_calling"); +#if defined (ARRAY_VARS) + else + { + restore_funcarray_state (fa); + /* Restore BASH_ARGC and BASH_ARGV */ + if (debugging_mode) + pop_args (); + } +#endif + + if (variable_context == 0 || this_shell_function == 0) + { + make_funcname_visible (0); +#if defined (PROCESS_SUBSTITUTION) + unlink_fifo_list (); +#endif + } + + return (result); +} + +/* A convenience routine for use by other parts of the shell to execute + a particular shell function. */ +int +execute_shell_function (var, words) + SHELL_VAR *var; + WORD_LIST *words; +{ + int ret; + struct fd_bitmap *bitmap; + + bitmap = new_fd_bitmap (FD_BITMAP_DEFAULT_SIZE); + begin_unwind_frame ("execute-shell-function"); + add_unwind_protect (dispose_fd_bitmap, (char *)bitmap); + + ret = execute_function (var, words, 0, bitmap, 0, 0); + + dispose_fd_bitmap (bitmap); + discard_unwind_frame ("execute-shell-function"); + + return ret; +} + +/* Execute a shell builtin or function in a subshell environment. This + routine does not return; it only calls exit(). If BUILTIN is non-null, + it points to a function to call to execute a shell builtin; otherwise + VAR points at the body of a function to execute. WORDS is the arguments + to the command, REDIRECTS specifies redirections to perform before the + command is executed. */ +static void +execute_subshell_builtin_or_function (words, redirects, builtin, var, + pipe_in, pipe_out, async, fds_to_close, + flags) + WORD_LIST *words; + REDIRECT *redirects; + sh_builtin_func_t *builtin; + SHELL_VAR *var; + int pipe_in, pipe_out, async; + struct fd_bitmap *fds_to_close; + int flags; +{ + int result, r, funcvalue; +#if defined (JOB_CONTROL) + int jobs_hack; + + jobs_hack = (builtin == jobs_builtin) && + ((subshell_environment & SUBSHELL_ASYNC) == 0 || pipe_out != NO_PIPE); +#endif + + /* A subshell is neither a login shell nor interactive. */ + login_shell = interactive = 0; + if (builtin == eval_builtin) + evalnest = 0; + else if (builtin == source_builtin) + sourcenest = 0; + + if (async) + subshell_environment |= SUBSHELL_ASYNC; + if (pipe_in != NO_PIPE || pipe_out != NO_PIPE) + subshell_environment |= SUBSHELL_PIPE; + + maybe_make_export_env (); /* XXX - is this needed? */ + +#if defined (JOB_CONTROL) + /* Eradicate all traces of job control after we fork the subshell, so + all jobs begun by this subshell are in the same process group as + the shell itself. */ + + /* Allow the output of `jobs' to be piped. */ + if (jobs_hack) + kill_current_pipeline (); + else + without_job_control (); + + set_sigchld_handler (); +#else + without_job_control (); +#endif /* JOB_CONTROL */ + + set_sigint_handler (); + + if (fds_to_close) + close_fd_bitmap (fds_to_close); + + do_piping (pipe_in, pipe_out); + + if (do_redirections (redirects, RX_ACTIVE) != 0) + exit (EXECUTION_FAILURE); + + if (builtin) + { + /* Give builtins a place to jump back to on failure, + so we don't go back up to main(). */ + result = setjmp_nosigs (top_level); + + /* Give the return builtin a place to jump to when executed in a subshell + or pipeline */ + funcvalue = 0; + if (return_catch_flag && builtin == return_builtin) + funcvalue = setjmp_nosigs (return_catch); + + if (result == EXITPROG) + exit (last_command_exit_value); + else if (result) + exit (EXECUTION_FAILURE); + else if (funcvalue) + exit (return_catch_value); + else + { + r = execute_builtin (builtin, words, flags, 1); + fflush (stdout); + if (r == EX_USAGE) + r = EX_BADUSAGE; + /* XXX - experimental */ + else if (r == EX_DISKFALLBACK) + { + char *command_line; + + command_line = savestring (the_printed_command_except_trap ? the_printed_command_except_trap : ""); + r = execute_disk_command (words, (REDIRECT *)0, command_line, + -1, -1, async, (struct fd_bitmap *)0, flags|CMD_NO_FORK); + } + sh_exit (r); + } + } + else + { + r = execute_function (var, words, flags, fds_to_close, async, 1); + fflush (stdout); + sh_exit (r); + } +} + +/* Execute a builtin or function in the current shell context. If BUILTIN + is non-null, it is the builtin command to execute, otherwise VAR points + to the body of a function. WORDS are the command's arguments, REDIRECTS + are the redirections to perform. FDS_TO_CLOSE is the usual bitmap of + file descriptors to close. + + If BUILTIN is exec_builtin, the redirections specified in REDIRECTS are + not undone before this function returns. */ +static int +execute_builtin_or_function (words, builtin, var, redirects, + fds_to_close, flags) + WORD_LIST *words; + sh_builtin_func_t *builtin; + SHELL_VAR *var; + REDIRECT *redirects; + struct fd_bitmap *fds_to_close; + int flags; +{ + int result; + REDIRECT *saved_undo_list; +#if defined (PROCESS_SUBSTITUTION) + int ofifo, nfifo, osize; + char *ofifo_list; +#endif + +#if defined (PROCESS_SUBSTITUTION) + begin_unwind_frame ("saved_fifos"); + /* If we return, we longjmp and don't get a chance to restore the old + fifo list, so we add an unwind protect to free it */ + ofifo = num_fifos (); + ofifo_list = copy_fifo_list (&osize); + if (ofifo_list) + add_unwind_protect (xfree, ofifo_list); +#endif + + if (do_redirections (redirects, RX_ACTIVE|RX_UNDOABLE) != 0) + { + undo_partial_redirects (); + dispose_exec_redirects (); +#if defined (PROCESS_SUBSTITUTION) + free (ofifo_list); +#endif + return (EX_REDIRFAIL); /* was EXECUTION_FAILURE */ + } + + saved_undo_list = redirection_undo_list; + + /* Calling the "exec" builtin changes redirections forever. */ + if (builtin == exec_builtin) + { + dispose_redirects (saved_undo_list); + saved_undo_list = exec_redirection_undo_list; + exec_redirection_undo_list = (REDIRECT *)NULL; + } + else + dispose_exec_redirects (); + + if (saved_undo_list) + { + begin_unwind_frame ("saved-redirects"); + add_unwind_protect (cleanup_redirects, (char *)saved_undo_list); + } + + redirection_undo_list = (REDIRECT *)NULL; + + if (builtin) + result = execute_builtin (builtin, words, flags, 0); + else + result = execute_function (var, words, flags, fds_to_close, 0, 0); + + /* We do this before undoing the effects of any redirections. */ + fflush (stdout); + fpurge (stdout); + if (ferror (stdout)) + clearerr (stdout); + + /* If we are executing the `command' builtin, but this_shell_builtin is + set to `exec_builtin', we know that we have something like + `command exec [redirection]', since otherwise `exec' would have + overwritten the shell and we wouldn't get here. In this case, we + want to behave as if the `command' builtin had not been specified + and preserve the redirections. */ + if (builtin == command_builtin && this_shell_builtin == exec_builtin) + { + int discard; + + discard = 0; + if (saved_undo_list) + { + dispose_redirects (saved_undo_list); + discard = 1; + } + redirection_undo_list = exec_redirection_undo_list; + saved_undo_list = exec_redirection_undo_list = (REDIRECT *)NULL; + if (discard) + discard_unwind_frame ("saved-redirects"); + } + + if (saved_undo_list) + { + redirection_undo_list = saved_undo_list; + discard_unwind_frame ("saved-redirects"); + } + + undo_partial_redirects (); + +#if defined (PROCESS_SUBSTITUTION) + /* Close any FIFOs created by this builtin or function. */ + nfifo = num_fifos (); + if (nfifo > ofifo) + close_new_fifos (ofifo_list, osize); + if (ofifo_list) + free (ofifo_list); + discard_unwind_frame ("saved_fifos"); +#endif + + return (result); +} + +void +setup_async_signals () +{ +#if defined (__BEOS__) + set_signal_handler (SIGHUP, SIG_IGN); /* they want csh-like behavior */ +#endif + +#if defined (JOB_CONTROL) + if (job_control == 0) +#endif + { + /* Make sure we get the original signal dispositions now so we don't + confuse the trap builtin later if the subshell tries to use it to + reset SIGINT/SIGQUIT. Don't call set_signal_ignored; that sets + the value of original_signals to SIG_IGN. Posix interpretation 751. */ + get_original_signal (SIGINT); + set_signal_handler (SIGINT, SIG_IGN); + + get_original_signal (SIGQUIT); + set_signal_handler (SIGQUIT, SIG_IGN); + } +} + +/* Execute a simple command that is hopefully defined in a disk file + somewhere. + + 1) fork () + 2) connect pipes + 3) look up the command + 4) do redirections + 5) execve () + 6) If the execve failed, see if the file has executable mode set. + If so, and it isn't a directory, then execute its contents as + a shell script. + + Note that the filename hashing stuff has to take place up here, + in the parent. This is probably why the Bourne style shells + don't handle it, since that would require them to go through + this gnarly hair, for no good reason. + + NOTE: callers expect this to fork or exit(). */ + +/* Name of a shell function to call when a command name is not found. */ +#ifndef NOTFOUND_HOOK +# define NOTFOUND_HOOK "command_not_found_handle" +#endif + +static int +execute_disk_command (words, redirects, command_line, pipe_in, pipe_out, + async, fds_to_close, cmdflags) + WORD_LIST *words; + REDIRECT *redirects; + char *command_line; + int pipe_in, pipe_out, async; + struct fd_bitmap *fds_to_close; + int cmdflags; +{ + char *pathname, *command, **args, *p; + int nofork, stdpath, result; + pid_t pid; + SHELL_VAR *hookf; + WORD_LIST *wl; + + stdpath = (cmdflags & CMD_STDPATH); /* use command -p path */ + nofork = (cmdflags & CMD_NO_FORK); /* Don't fork, just exec, if no pipes */ + pathname = words->word->word; + + p = 0; + result = EXECUTION_SUCCESS; +#if defined (RESTRICTED_SHELL) + command = (char *)NULL; + if (restricted && mbschr (pathname, '/')) + { + internal_error (_("%s: restricted: cannot specify `/' in command names"), + pathname); + result = last_command_exit_value = EXECUTION_FAILURE; + + /* If we're not going to fork below, we must already be in a child + process or a context in which it's safe to call exit(2). */ + if (nofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE) + exit (last_command_exit_value); + else + goto parent_return; + } +#endif /* RESTRICTED_SHELL */ + + command = search_for_command (pathname, CMDSRCH_HASH|(stdpath ? CMDSRCH_STDPATH : 0)); + QUIT; + + if (command) + { + /* If we're optimizing out the fork (implicit `exec'), decrement the + shell level like `exec' would do. */ + if (nofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE) + adjust_shell_level (-1); + + maybe_make_export_env (); + put_command_name_into_env (command); + } + + /* We have to make the child before we check for the non-existence + of COMMAND, since we want the error messages to be redirected. */ + /* If we can get away without forking and there are no pipes to deal with, + don't bother to fork, just directly exec the command. */ + if (nofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE) + pid = 0; + else + pid = make_child (p = savestring (command_line), async); + + if (pid == 0) + { + int old_interactive; + + reset_terminating_signals (); /* XXX */ + /* Cancel traps, in trap.c. */ + restore_original_signals (); + + CHECK_SIGTERM; + +#if defined (JOB_CONTROL) + FREE (p); +#endif + + /* restore_original_signals may have undone the work done + by make_child to ensure that SIGINT and SIGQUIT are ignored + in asynchronous children. */ + if (async) + { + if ((cmdflags & CMD_STDIN_REDIR) && + pipe_in == NO_PIPE && + (stdin_redirects (redirects) == 0)) + async_redirect_stdin (); + setup_async_signals (); + } + + /* This functionality is now provided by close-on-exec of the + file descriptors manipulated by redirection and piping. + Some file descriptors still need to be closed in all children + because of the way bash does pipes; fds_to_close is a + bitmap of all such file descriptors. */ + if (fds_to_close) + close_fd_bitmap (fds_to_close); + + do_piping (pipe_in, pipe_out); + + old_interactive = interactive; + if (async) + interactive = 0; + + subshell_environment |= SUBSHELL_FORK; /* XXX - was just = */ + + if (redirects && (do_redirections (redirects, RX_ACTIVE) != 0)) + { +#if defined (PROCESS_SUBSTITUTION) + /* Try to remove named pipes that may have been created as the + result of redirections. */ + unlink_fifo_list (); +#endif /* PROCESS_SUBSTITUTION */ + exit (EXECUTION_FAILURE); + } + + if (async) + interactive = old_interactive; + + if (command == 0) + { + hookf = find_function (NOTFOUND_HOOK); + if (hookf == 0) + { + /* Make sure filenames are displayed using printable characters */ + pathname = printable_filename (pathname, 0); + internal_error (_("%s: command not found"), pathname); + exit (EX_NOTFOUND); /* Posix.2 says the exit status is 127 */ + } + + /* We don't want to manage process groups for processes we start + from here, so we turn off job control and don't attempt to + manipulate the terminal's process group. */ + without_job_control (); + +#if defined (JOB_CONTROL) + set_sigchld_handler (); +#endif + + wl = make_word_list (make_word (NOTFOUND_HOOK), words); + exit (execute_shell_function (hookf, wl)); + } + + CHECK_SIGTERM; + + /* Execve expects the command name to be in args[0]. So we + leave it there, in the same format that the user used to + type it in. */ + args = strvec_from_word_list (words, 0, 0, (int *)NULL); + exit (shell_execve (command, args, export_env)); + } + else + { +parent_return: + QUIT; + + /* Make sure that the pipes are closed in the parent. */ + close_pipes (pipe_in, pipe_out); +#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD) +#if 0 + if (variable_context == 0) + unlink_fifo_list (); +#endif +#endif + FREE (command); + return (result); + } +} + +/* CPP defines to decide whether a particular index into the #! line + corresponds to a valid interpreter name or argument character, or + whitespace. The MSDOS define is to allow \r to be treated the same + as \n. */ + +#if !defined (MSDOS) +# define STRINGCHAR(ind) \ + (ind < sample_len && !whitespace (sample[ind]) && sample[ind] != '\n') +# define WHITECHAR(ind) \ + (ind < sample_len && whitespace (sample[ind])) +#else /* MSDOS */ +# define STRINGCHAR(ind) \ + (ind < sample_len && !whitespace (sample[ind]) && sample[ind] != '\n' && sample[ind] != '\r') +# define WHITECHAR(ind) \ + (ind < sample_len && whitespace (sample[ind])) +#endif /* MSDOS */ + +static char * +getinterp (sample, sample_len, endp) + char *sample; + int sample_len, *endp; +{ + register int i; + char *execname; + int start; + + /* Find the name of the interpreter to exec. */ + for (i = 2; i < sample_len && whitespace (sample[i]); i++) + ; + + for (start = i; STRINGCHAR(i); i++) + ; + + execname = substring (sample, start, i); + + if (endp) + *endp = i; + return execname; +} + +#if !defined (HAVE_HASH_BANG_EXEC) +/* If the operating system on which we're running does not handle + the #! executable format, then help out. SAMPLE is the text read + from the file, SAMPLE_LEN characters. COMMAND is the name of + the script; it and ARGS, the arguments given by the user, will + become arguments to the specified interpreter. ENV is the environment + to pass to the interpreter. + + The word immediately following the #! is the interpreter to execute. + A single argument to the interpreter is allowed. */ + +static int +execute_shell_script (sample, sample_len, command, args, env) + char *sample; + int sample_len; + char *command; + char **args, **env; +{ + char *execname, *firstarg; + int i, start, size_increment, larry; + + /* Find the name of the interpreter to exec. */ + execname = getinterp (sample, sample_len, &i); + size_increment = 1; + + /* Now the argument, if any. */ + for (firstarg = (char *)NULL, start = i; WHITECHAR(i); i++) + ; + + /* If there is more text on the line, then it is an argument for the + interpreter. */ + + if (STRINGCHAR(i)) + { + for (start = i; STRINGCHAR(i); i++) + ; + firstarg = substring ((char *)sample, start, i); + size_increment = 2; + } + + larry = strvec_len (args) + size_increment; + args = strvec_resize (args, larry + 1); + + for (i = larry - 1; i; i--) + args[i] = args[i - size_increment]; + + args[0] = execname; + if (firstarg) + { + args[1] = firstarg; + args[2] = command; + } + else + args[1] = command; + + args[larry] = (char *)NULL; + + return (shell_execve (execname, args, env)); +} +#undef STRINGCHAR +#undef WHITECHAR + +#endif /* !HAVE_HASH_BANG_EXEC */ + +static void +initialize_subshell () +{ +#if defined (ALIAS) + /* Forget about any aliases that we knew of. We are in a subshell. */ + delete_all_aliases (); +#endif /* ALIAS */ + +#if defined (HISTORY) + /* Forget about the history lines we have read. This is a non-interactive + subshell. */ + history_lines_this_session = 0; +#endif + + /* Forget about the way job control was working. We are in a subshell. */ + without_job_control (); + +#if defined (JOB_CONTROL) + set_sigchld_handler (); + init_job_stats (); +#endif /* JOB_CONTROL */ + + /* Reset the values of the shell flags and options. */ + reset_shell_flags (); + reset_shell_options (); + reset_shopt_options (); + + /* Zero out builtin_env, since this could be a shell script run from a + sourced file with a temporary environment supplied to the `source/.' + builtin. Such variables are not supposed to be exported (empirical + testing with sh and ksh). Just throw it away; don't worry about a + memory leak. */ + if (vc_isbltnenv (shell_variables)) + shell_variables = shell_variables->down; + + clear_unwind_protect_list (0); + /* XXX -- are there other things we should be resetting here? */ + parse_and_execute_level = 0; /* nothing left to restore it */ + + /* We're no longer inside a shell function. */ + variable_context = return_catch_flag = funcnest = evalnest = sourcenest = 0; + + executing_list = 0; /* XXX */ + + /* If we're not interactive, close the file descriptor from which we're + reading the current shell script. */ + if (interactive_shell == 0) + unset_bash_input (0); +} + +#if defined (HAVE_SETOSTYPE) && defined (_POSIX_SOURCE) +# define SETOSTYPE(x) __setostype(x) +#else +# define SETOSTYPE(x) +#endif + +#define HASH_BANG_BUFSIZ 128 + +#define READ_SAMPLE_BUF(file, buf, len) \ + do \ + { \ + fd = open(file, O_RDONLY); \ + if (fd >= 0) \ + { \ + len = read (fd, buf, HASH_BANG_BUFSIZ); \ + close (fd); \ + } \ + else \ + len = -1; \ + } \ + while (0) + +/* Call execve (), handling interpreting shell scripts, and handling + exec failures. */ +int +shell_execve (command, args, env) + char *command; + char **args, **env; +{ + int larray, i, fd; + char sample[HASH_BANG_BUFSIZ]; + int sample_len; + + SETOSTYPE (0); /* Some systems use for USG/POSIX semantics */ + execve (command, args, env); + i = errno; /* error from execve() */ + CHECK_TERMSIG; + SETOSTYPE (1); + + /* If we get to this point, then start checking out the file. + Maybe it is something we can hack ourselves. */ + if (i != ENOEXEC) + { + /* make sure this is set correctly for file_error/report_error */ + last_command_exit_value = (i == ENOENT) ? EX_NOTFOUND : EX_NOEXEC; /* XXX Posix.2 says that exit status is 126 */ + if (file_isdir (command)) +#if defined (EISDIR) + internal_error (_("%s: %s"), command, strerror (EISDIR)); +#else + internal_error (_("%s: is a directory"), command); +#endif + else if (executable_file (command) == 0) + { + errno = i; + file_error (command); + } + /* errors not involving the path argument to execve. */ + else if (i == E2BIG || i == ENOMEM) + { + errno = i; + file_error (command); + } + else + { + /* The file has the execute bits set, but the kernel refuses to + run it for some reason. See why. */ +#if defined (HAVE_HASH_BANG_EXEC) + READ_SAMPLE_BUF (command, sample, sample_len); + if (sample_len > 0) + sample[sample_len - 1] = '\0'; + if (sample_len > 2 && sample[0] == '#' && sample[1] == '!') + { + char *interp; + int ilen; + + interp = getinterp (sample, sample_len, (int *)NULL); + ilen = strlen (interp); + errno = i; + if (interp[ilen - 1] == '\r') + { + interp = xrealloc (interp, ilen + 2); + interp[ilen - 1] = '^'; + interp[ilen] = 'M'; + interp[ilen + 1] = '\0'; + } + sys_error (_("%s: %s: bad interpreter"), command, interp ? interp : ""); + FREE (interp); + return (EX_NOEXEC); + } +#endif + errno = i; + file_error (command); + } + return (last_command_exit_value); + } + + /* This file is executable. + If it begins with #!, then help out people with losing operating + systems. Otherwise, check to see if it is a binary file by seeing + if the contents of the first line (or up to 80 characters) are in the + ASCII set. If it's a text file, execute the contents as shell commands, + otherwise return 126 (EX_BINARY_FILE). */ + READ_SAMPLE_BUF (command, sample, sample_len); + + if (sample_len == 0) + return (EXECUTION_SUCCESS); + + /* Is this supposed to be an executable script? + If so, the format of the line is "#! interpreter [argument]". + A single argument is allowed. The BSD kernel restricts + the length of the entire line to 32 characters (32 bytes + being the size of the BSD exec header), but we allow 80 + characters. */ + if (sample_len > 0) + { +#if !defined (HAVE_HASH_BANG_EXEC) + if (sample_len > 2 && sample[0] == '#' && sample[1] == '!') + return (execute_shell_script (sample, sample_len, command, args, env)); + else +#endif + if (check_binary_file (sample, sample_len)) + { + internal_error (_("%s: cannot execute binary file: %s"), command, strerror (i)); + errno = i; + return (EX_BINARY_FILE); + } + } + + /* We have committed to attempting to execute the contents of this file + as shell commands. */ + + reset_parser (); + initialize_subshell (); + + set_sigint_handler (); + + /* Insert the name of this shell into the argument list. */ + larray = strvec_len (args) + 1; + args = strvec_resize (args, larray + 1); + + for (i = larray - 1; i; i--) + args[i] = args[i - 1]; + + args[0] = shell_name; + args[1] = command; + args[larray] = (char *)NULL; + + if (args[0][0] == '-') + args[0]++; + +#if defined (RESTRICTED_SHELL) + if (restricted) + change_flag ('r', FLAG_OFF); +#endif + + if (subshell_argv) + { + /* Can't free subshell_argv[0]; that is shell_name. */ + for (i = 1; i < subshell_argc; i++) + free (subshell_argv[i]); + free (subshell_argv); + } + + dispose_command (currently_executing_command); /* XXX */ + currently_executing_command = (COMMAND *)NULL; + + subshell_argc = larray; + subshell_argv = args; + subshell_envp = env; + + unbind_args (); /* remove the positional parameters */ + +#if defined (PROCESS_SUBSTITUTION) + clear_fifo_list (); /* pipe fds are what they are now */ +#endif + + sh_longjmp (subshell_top_level, 1); + /*NOTREACHED*/ +} + +static int +execute_intern_function (name, funcdef) + WORD_DESC *name; + FUNCTION_DEF *funcdef; +{ + SHELL_VAR *var; + char *t; + + if (check_identifier (name, posixly_correct) == 0) + { + if (posixly_correct && interactive_shell == 0) + { + last_command_exit_value = EX_BADUSAGE; + jump_to_top_level (ERREXIT); + } + return (EXECUTION_FAILURE); + } + + if (strchr (name->word, CTLESC)) /* WHY? */ + { + t = dequote_escapes (name->word); + free (name->word); + name->word = t; + } + + /* Posix interpretation 383 */ + if (posixly_correct && find_special_builtin (name->word)) + { + internal_error (_("`%s': is a special builtin"), name->word); + last_command_exit_value = EX_BADUSAGE; + jump_to_top_level (interactive_shell ? DISCARD : ERREXIT); + } + + var = find_function (name->word); + if (var && (readonly_p (var) || noassign_p (var))) + { + if (readonly_p (var)) + internal_error (_("%s: readonly function"), var->name); + return (EXECUTION_FAILURE); + } + +#if defined (DEBUGGER) + bind_function_def (name->word, funcdef, 1); +#endif + + bind_function (name->word, funcdef->command); + return (EXECUTION_SUCCESS); +} + +#if defined (INCLUDE_UNUSED) +#if defined (PROCESS_SUBSTITUTION) +void +close_all_files () +{ + register int i, fd_table_size; + + fd_table_size = getdtablesize (); + if (fd_table_size > 256) /* clamp to a reasonable value */ + fd_table_size = 256; + + for (i = 3; i < fd_table_size; i++) + close (i); +} +#endif /* PROCESS_SUBSTITUTION */ +#endif + +static void +close_pipes (in, out) + int in, out; +{ + if (in >= 0) + close (in); + if (out >= 0) + close (out); +} + +static void +dup_error (oldd, newd) + int oldd, newd; +{ + sys_error (_("cannot duplicate fd %d to fd %d"), oldd, newd); +} + +/* Redirect input and output to be from and to the specified pipes. + NO_PIPE and REDIRECT_BOTH are handled correctly. */ +static void +do_piping (pipe_in, pipe_out) + int pipe_in, pipe_out; +{ + if (pipe_in != NO_PIPE) + { + if (dup2 (pipe_in, 0) < 0) + dup_error (pipe_in, 0); + if (pipe_in > 0) + close (pipe_in); +#ifdef __CYGWIN__ + /* Let stdio know the fd may have changed from text to binary mode. */ + freopen (NULL, "r", stdin); +#endif /* __CYGWIN__ */ + } + if (pipe_out != NO_PIPE) + { + if (pipe_out != REDIRECT_BOTH) + { + if (dup2 (pipe_out, 1) < 0) + dup_error (pipe_out, 1); + if (pipe_out == 0 || pipe_out > 1) + close (pipe_out); + } + else + { + if (dup2 (1, 2) < 0) + dup_error (1, 2); + } +#ifdef __CYGWIN__ + /* Let stdio know the fd may have changed from text to binary mode, and + make sure to preserve stdout line buffering. */ + freopen (NULL, "w", stdout); + sh_setlinebuf (stdout); +#endif /* __CYGWIN__ */ + } +} |