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Diffstat (limited to 'builtins/common.c')
| -rw-r--r-- | builtins/common.c | 1017 |
1 files changed, 1017 insertions, 0 deletions
diff --git a/builtins/common.c b/builtins/common.c new file mode 100644 index 0000000..3c9ac49 --- /dev/null +++ b/builtins/common.c @@ -0,0 +1,1017 @@ +/* common.c - utility functions for all builtins */ + +/* Copyright (C) 1987-2020 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 (HAVE_UNISTD_H) +# ifdef _MINIX +# include <sys/types.h> +# endif +# include <unistd.h> +#endif + +#include <stdio.h> +#include <chartypes.h> +#include "../bashtypes.h" +#include "posixstat.h" +#include <signal.h> + +#include <errno.h> + +#if defined (PREFER_STDARG) +# include <stdarg.h> +#else +# include <varargs.h> +#endif + +#include "../bashansi.h" +#include "../bashintl.h" + +#define NEED_FPURGE_DECL + +#include "../shell.h" +#include "maxpath.h" +#include "../flags.h" +#include "../parser.h" +#include "../jobs.h" +#include "../builtins.h" +#include "../input.h" +#include "../execute_cmd.h" +#include "../trap.h" +#include "bashgetopt.h" +#include "common.h" +#include "builtext.h" +#include <tilde/tilde.h> + +#if defined (HISTORY) +# include "../bashhist.h" +#endif + +#if !defined (errno) +extern int errno; +#endif /* !errno */ + +extern const char * const bash_getcwd_errstr; + +/* Used by some builtins and the mainline code. */ +sh_builtin_func_t *last_shell_builtin = (sh_builtin_func_t *)NULL; +sh_builtin_func_t *this_shell_builtin = (sh_builtin_func_t *)NULL; + +/* **************************************************************** */ +/* */ +/* Error reporting, usage, and option processing */ +/* */ +/* **************************************************************** */ + +/* This is a lot like report_error (), but it is for shell builtins + instead of shell control structures, and it won't ever exit the + shell. */ + +static void +builtin_error_prolog () +{ + char *name; + + name = get_name_for_error (); + fprintf (stderr, "%s: ", name); + + if (interactive_shell == 0) + fprintf (stderr, _("line %d: "), executing_line_number ()); + + if (this_command_name && *this_command_name) + fprintf (stderr, "%s: ", this_command_name); +} + +void +#if defined (PREFER_STDARG) +builtin_error (const char *format, ...) +#else +builtin_error (format, va_alist) + const char *format; + va_dcl +#endif +{ + va_list args; + + builtin_error_prolog (); + + SH_VA_START (args, format); + + vfprintf (stderr, format, args); + va_end (args); + fprintf (stderr, "\n"); +} + +void +#if defined (PREFER_STDARG) +builtin_warning (const char *format, ...) +#else +builtin_warning (format, va_alist) + const char *format; + va_dcl +#endif +{ + va_list args; + + builtin_error_prolog (); + fprintf (stderr, _("warning: ")); + + SH_VA_START (args, format); + + vfprintf (stderr, format, args); + va_end (args); + fprintf (stderr, "\n"); +} + +/* Print a usage summary for the currently-executing builtin command. */ +void +builtin_usage () +{ + if (this_command_name && *this_command_name) + fprintf (stderr, _("%s: usage: "), this_command_name); + fprintf (stderr, "%s\n", _(current_builtin->short_doc)); + fflush (stderr); +} + +/* Return if LIST is NULL else barf and jump to top_level. Used by some + builtins that do not accept arguments. */ +void +no_args (list) + WORD_LIST *list; +{ + if (list) + { + builtin_error (_("too many arguments")); + top_level_cleanup (); + jump_to_top_level (DISCARD); + } +} + +/* Check that no options were given to the currently-executing builtin, + and return 0 if there were options. */ +int +no_options (list) + WORD_LIST *list; +{ + int opt; + + reset_internal_getopt (); + if ((opt = internal_getopt (list, "")) != -1) + { + if (opt == GETOPT_HELP) + { + builtin_help (); + return (2); + } + builtin_usage (); + return (1); + } + return (0); +} + +void +sh_needarg (s) + char *s; +{ + builtin_error (_("%s: option requires an argument"), s); +} + +void +sh_neednumarg (s) + char *s; +{ + builtin_error (_("%s: numeric argument required"), s); +} + +void +sh_notfound (s) + char *s; +{ + builtin_error (_("%s: not found"), s); +} + +/* Function called when one of the builtin commands detects an invalid + option. */ +void +sh_invalidopt (s) + char *s; +{ + builtin_error (_("%s: invalid option"), s); +} + +void +sh_invalidoptname (s) + char *s; +{ + builtin_error (_("%s: invalid option name"), s); +} + +void +sh_invalidid (s) + char *s; +{ + builtin_error (_("`%s': not a valid identifier"), s); +} + +void +sh_invalidnum (s) + char *s; +{ + char *msg; + + if (*s == '0' && isdigit ((unsigned char)s[1])) + msg = _("invalid octal number"); + else if (*s == '0' && s[1] == 'x') + msg = _("invalid hex number"); + else + msg = _("invalid number"); + builtin_error ("%s: %s", s, msg); +} + +void +sh_invalidsig (s) + char *s; +{ + builtin_error (_("%s: invalid signal specification"), s); +} + +void +sh_badpid (s) + char *s; +{ + builtin_error (_("`%s': not a pid or valid job spec"), s); +} + +void +sh_readonly (s) + const char *s; +{ + builtin_error (_("%s: readonly variable"), s); +} + +void +sh_erange (s, desc) + char *s, *desc; +{ + if (s) + builtin_error (_("%s: %s out of range"), s, desc ? desc : _("argument")); + else + builtin_error (_("%s out of range"), desc ? desc : _("argument")); +} + +#if defined (JOB_CONTROL) +void +sh_badjob (s) + char *s; +{ + builtin_error (_("%s: no such job"), s); +} + +void +sh_nojobs (s) + char *s; +{ + if (s) + builtin_error (_("%s: no job control"), s); + else + builtin_error (_("no job control")); +} +#endif + +#if defined (RESTRICTED_SHELL) +void +sh_restricted (s) + char *s; +{ + if (s) + builtin_error (_("%s: restricted"), s); + else + builtin_error (_("restricted")); +} +#endif + +void +sh_notbuiltin (s) + char *s; +{ + builtin_error (_("%s: not a shell builtin"), s); +} + +void +sh_wrerror () +{ +#if defined (DONT_REPORT_BROKEN_PIPE_WRITE_ERRORS) && defined (EPIPE) + if (errno != EPIPE) +#endif /* DONT_REPORT_BROKEN_PIPE_WRITE_ERRORS && EPIPE */ + builtin_error (_("write error: %s"), strerror (errno)); +} + +void +sh_ttyerror (set) + int set; +{ + if (set) + builtin_error (_("error setting terminal attributes: %s"), strerror (errno)); + else + builtin_error (_("error getting terminal attributes: %s"), strerror (errno)); +} + +int +sh_chkwrite (s) + int s; +{ + QUIT; + fflush (stdout); + QUIT; + if (ferror (stdout)) + { + sh_wrerror (); + fpurge (stdout); + clearerr (stdout); + return (EXECUTION_FAILURE); + } + return (s); +} + +/* **************************************************************** */ +/* */ +/* Shell positional parameter manipulation */ +/* */ +/* **************************************************************** */ + +/* Convert a WORD_LIST into a C-style argv. Return the number of elements + in the list in *IP, if IP is non-null. A convenience function for + loadable builtins; also used by `test'. */ +char ** +make_builtin_argv (list, ip) + WORD_LIST *list; + int *ip; +{ + char **argv; + + argv = strvec_from_word_list (list, 0, 1, ip); + argv[0] = this_command_name; + return argv; +} + +/* Remember LIST in $1 ... $9, and REST_OF_ARGS. If DESTRUCTIVE is + non-zero, then discard whatever the existing arguments are, else + only discard the ones that are to be replaced. Set POSPARAM_COUNT + to the number of args assigned (length of LIST). */ +void +remember_args (list, destructive) + WORD_LIST *list; + int destructive; +{ + register int i; + + posparam_count = 0; + + for (i = 1; i < 10; i++) + { + if ((destructive || list) && dollar_vars[i]) + { + free (dollar_vars[i]); + dollar_vars[i] = (char *)NULL; + } + + if (list) + { + dollar_vars[posparam_count = i] = savestring (list->word->word); + list = list->next; + } + } + + /* If arguments remain, assign them to REST_OF_ARGS. + Note that copy_word_list (NULL) returns NULL, and + that dispose_words (NULL) does nothing. */ + if (destructive || list) + { + dispose_words (rest_of_args); + rest_of_args = copy_word_list (list); + posparam_count += list_length (list); + } + + if (destructive) + set_dollar_vars_changed (); + + invalidate_cached_quoted_dollar_at (); +} + +void +shift_args (times) + int times; +{ + WORD_LIST *temp; + int count; + + if (times <= 0) /* caller should check */ + return; + + while (times-- > 0) + { + if (dollar_vars[1]) + free (dollar_vars[1]); + + for (count = 1; count < 9; count++) + dollar_vars[count] = dollar_vars[count + 1]; + + if (rest_of_args) + { + temp = rest_of_args; + dollar_vars[9] = savestring (temp->word->word); + rest_of_args = rest_of_args->next; + temp->next = (WORD_LIST *)NULL; + dispose_words (temp); + } + else + dollar_vars[9] = (char *)NULL; + + posparam_count--; + } +} + +int +number_of_args () +{ +#ifdef DEBUG + register WORD_LIST *list; + int n; + + for (n = 0; n < 9 && dollar_vars[n+1]; n++) + ; + for (list = rest_of_args; list; list = list->next) + n++; + +if (n != posparam_count) + itrace("number_of_args: n (%d) != posparam_count (%d)", n, posparam_count); +#endif + + return posparam_count; +} + +static int changed_dollar_vars; + +/* Have the dollar variables been reset to new values since we last + checked? */ +int +dollar_vars_changed () +{ + return (changed_dollar_vars); +} + +void +set_dollar_vars_unchanged () +{ + changed_dollar_vars = 0; +} + +void +set_dollar_vars_changed () +{ + if (variable_context) + changed_dollar_vars |= ARGS_FUNC; + else if (this_shell_builtin == set_builtin) + changed_dollar_vars |= ARGS_SETBLTIN; + else + changed_dollar_vars |= ARGS_INVOC; +} + +/* **************************************************************** */ +/* */ +/* Validating numeric input and arguments */ +/* */ +/* **************************************************************** */ + +/* Read a numeric arg for this_command_name, the name of the shell builtin + that wants it. LIST is the word list that the arg is to come from. + Accept only the numeric argument; report an error if other arguments + follow. If FATAL is 1, call throw_to_top_level, which exits the + shell; if it's 2, call jump_to_top_level (DISCARD), which aborts the + current command; if FATAL is 0, return an indication of an invalid + number by setting *NUMOK == 0 and return -1. */ +int +get_numeric_arg (list, fatal, count) + WORD_LIST *list; + int fatal; + intmax_t *count; +{ + char *arg; + + if (count) + *count = 1; + + if (list && list->word && ISOPTION (list->word->word, '-')) + list = list->next; + + if (list) + { + arg = list->word->word; + if (arg == 0 || (legal_number (arg, count) == 0)) + { + sh_neednumarg (list->word->word ? list->word->word : "`'"); + if (fatal == 0) + return 0; + else if (fatal == 1) /* fatal == 1; abort */ + throw_to_top_level (); + else /* fatal == 2; discard current command */ + { + top_level_cleanup (); + jump_to_top_level (DISCARD); + } + } + no_args (list->next); + } + + return (1); +} + +/* Get an eight-bit status value from LIST */ +int +get_exitstat (list) + WORD_LIST *list; +{ + int status; + intmax_t sval; + char *arg; + + if (list && list->word && ISOPTION (list->word->word, '-')) + list = list->next; + + if (list == 0) + { + /* If we're not running the DEBUG trap, the return builtin, when not + given any arguments, uses the value of $? before the trap ran. If + given an argument, return uses it. This means that the trap can't + change $?. The DEBUG trap gets to change $?, though, since that is + part of its reason for existing, and because the extended debug mode + does things with the return value. */ + if (this_shell_builtin == return_builtin && running_trap > 0 && running_trap != DEBUG_TRAP+1) + return (trap_saved_exit_value); + return (last_command_exit_value); + } + + arg = list->word->word; + if (arg == 0 || legal_number (arg, &sval) == 0) + { + sh_neednumarg (list->word->word ? list->word->word : "`'"); + return EX_BADUSAGE; + } + no_args (list->next); + + status = sval & 255; + return status; +} + +/* Return the octal number parsed from STRING, or -1 to indicate + that the string contained a bad number. */ +int +read_octal (string) + char *string; +{ + int result, digits; + + result = digits = 0; + while (*string && ISOCTAL (*string)) + { + digits++; + result = (result * 8) + (*string++ - '0'); + if (result > 07777) + return -1; + } + + if (digits == 0 || *string) + result = -1; + + return (result); +} + +/* **************************************************************** */ +/* */ +/* Manipulating the current working directory */ +/* */ +/* **************************************************************** */ + +/* Return a consed string which is the current working directory. + FOR_WHOM is the name of the caller for error printing. */ +char *the_current_working_directory = (char *)NULL; + +char * +get_working_directory (for_whom) + char *for_whom; +{ + if (no_symbolic_links) + { + FREE (the_current_working_directory); + the_current_working_directory = (char *)NULL; + } + + if (the_current_working_directory == 0) + { +#if defined (GETCWD_BROKEN) + the_current_working_directory = getcwd (0, PATH_MAX); +#else + the_current_working_directory = getcwd (0, 0); +#endif + if (the_current_working_directory == 0) + { + fprintf (stderr, _("%s: error retrieving current directory: %s: %s\n"), + (for_whom && *for_whom) ? for_whom : get_name_for_error (), + _(bash_getcwd_errstr), strerror (errno)); + return (char *)NULL; + } + } + + return (savestring (the_current_working_directory)); +} + +/* Make NAME our internal idea of the current working directory. */ +void +set_working_directory (name) + char *name; +{ + FREE (the_current_working_directory); + the_current_working_directory = savestring (name); +} + +/* **************************************************************** */ +/* */ +/* Job control support functions */ +/* */ +/* **************************************************************** */ + +#if defined (JOB_CONTROL) +int +get_job_by_name (name, flags) + const char *name; + int flags; +{ + register int i, wl, cl, match, job; + register PROCESS *p; + register JOB *j; + + job = NO_JOB; + wl = strlen (name); + for (i = js.j_jobslots - 1; i >= 0; i--) + { + j = get_job_by_jid (i); + if (j == 0 || ((flags & JM_STOPPED) && J_JOBSTATE(j) != JSTOPPED)) + continue; + + p = j->pipe; + do + { + if (flags & JM_EXACT) + { + cl = strlen (p->command); + match = STREQN (p->command, name, cl); + } + else if (flags & JM_SUBSTRING) + match = strcasestr (p->command, name) != (char *)0; + else + match = STREQN (p->command, name, wl); + + if (match == 0) + { + p = p->next; + continue; + } + else if (flags & JM_FIRSTMATCH) + return i; /* return first match */ + else if (job != NO_JOB) + { + if (this_shell_builtin) + builtin_error (_("%s: ambiguous job spec"), name); + else + internal_error (_("%s: ambiguous job spec"), name); + return (DUP_JOB); + } + else + job = i; + } + while (p != j->pipe); + } + + return (job); +} + +/* Return the job spec found in LIST. */ +int +get_job_spec (list) + WORD_LIST *list; +{ + register char *word; + int job, jflags; + + if (list == 0) + return (js.j_current); + + word = list->word->word; + + if (*word == '\0') + return (NO_JOB); + + if (*word == '%') + word++; + + if (DIGIT (*word) && all_digits (word)) + { + job = atoi (word); + return ((job < 0 || job > js.j_jobslots) ? NO_JOB : job - 1); + } + + jflags = 0; + switch (*word) + { + case 0: + case '%': + case '+': + return (js.j_current); + + case '-': + return (js.j_previous); + + case '?': /* Substring search requested. */ + jflags |= JM_SUBSTRING; + word++; + /* FALLTHROUGH */ + + default: + return get_job_by_name (word, jflags); + } +} +#endif /* JOB_CONTROL */ + +/* + * NOTE: `kill' calls this function with forcecols == 0 + */ +int +display_signal_list (list, forcecols) + WORD_LIST *list; + int forcecols; +{ + register int i, column; + char *name; + int result, signum, dflags; + intmax_t lsignum; + + result = EXECUTION_SUCCESS; + if (!list) + { + for (i = 1, column = 0; i < NSIG; i++) + { + name = signal_name (i); + if (STREQN (name, "SIGJUNK", 7) || STREQN (name, "Unknown", 7)) + continue; + + if (posixly_correct && !forcecols) + { + /* This is for the kill builtin. POSIX.2 says the signal names + are displayed without the `SIG' prefix. */ + if (STREQN (name, "SIG", 3)) + name += 3; + printf ("%s%s", name, (i == NSIG - 1) ? "" : " "); + } + else + { + printf ("%2d) %s", i, name); + + if (++column < 5) + printf ("\t"); + else + { + printf ("\n"); + column = 0; + } + } + } + + if ((posixly_correct && !forcecols) || column != 0) + printf ("\n"); + return result; + } + + /* List individual signal names or numbers. */ + while (list) + { + if (legal_number (list->word->word, &lsignum)) + { + /* This is specified by Posix.2 so that exit statuses can be + mapped into signal numbers. */ + if (lsignum > 128) + lsignum -= 128; + if (lsignum < 0 || lsignum >= NSIG) + { + sh_invalidsig (list->word->word); + result = EXECUTION_FAILURE; + list = list->next; + continue; + } + + signum = lsignum; + name = signal_name (signum); + if (STREQN (name, "SIGJUNK", 7) || STREQN (name, "Unknown", 7)) + { + list = list->next; + continue; + } + /* POSIX.2 says that `kill -l signum' prints the signal name without + the `SIG' prefix. */ + printf ("%s\n", (this_shell_builtin == kill_builtin && signum > 0) ? name + 3 : name); + } + else + { + dflags = DSIG_NOCASE; + if (posixly_correct == 0 || this_shell_builtin != kill_builtin) + dflags |= DSIG_SIGPREFIX; + signum = decode_signal (list->word->word, dflags); + if (signum == NO_SIG) + { + sh_invalidsig (list->word->word); + result = EXECUTION_FAILURE; + list = list->next; + continue; + } + printf ("%d\n", signum); + } + list = list->next; + } + return (result); +} + +/* **************************************************************** */ +/* */ +/* Finding builtin commands and their functions */ +/* */ +/* **************************************************************** */ + +/* Perform a binary search and return the address of the builtin function + whose name is NAME. If the function couldn't be found, or the builtin + is disabled or has no function associated with it, return NULL. + Return the address of the builtin. + DISABLED_OKAY means find it even if the builtin is disabled. */ +struct builtin * +builtin_address_internal (name, disabled_okay) + char *name; + int disabled_okay; +{ + int hi, lo, mid, j; + + hi = num_shell_builtins - 1; + lo = 0; + + while (lo <= hi) + { + mid = (lo + hi) / 2; + + j = shell_builtins[mid].name[0] - name[0]; + + if (j == 0) + j = strcmp (shell_builtins[mid].name, name); + + if (j == 0) + { + /* It must have a function pointer. It must be enabled, or we + must have explicitly allowed disabled functions to be found, + and it must not have been deleted. */ + if (shell_builtins[mid].function && + ((shell_builtins[mid].flags & BUILTIN_DELETED) == 0) && + ((shell_builtins[mid].flags & BUILTIN_ENABLED) || disabled_okay)) + return (&shell_builtins[mid]); + else + return ((struct builtin *)NULL); + } + if (j > 0) + hi = mid - 1; + else + lo = mid + 1; + } + return ((struct builtin *)NULL); +} + +/* Return the pointer to the function implementing builtin command NAME. */ +sh_builtin_func_t * +find_shell_builtin (name) + char *name; +{ + current_builtin = builtin_address_internal (name, 0); + return (current_builtin ? current_builtin->function : (sh_builtin_func_t *)NULL); +} + +/* Return the address of builtin with NAME, whether it is enabled or not. */ +sh_builtin_func_t * +builtin_address (name) + char *name; +{ + current_builtin = builtin_address_internal (name, 1); + return (current_builtin ? current_builtin->function : (sh_builtin_func_t *)NULL); +} + +/* Return the function implementing the builtin NAME, but only if it is a + POSIX.2 special builtin. */ +sh_builtin_func_t * +find_special_builtin (name) + char *name; +{ + current_builtin = builtin_address_internal (name, 0); + return ((current_builtin && (current_builtin->flags & SPECIAL_BUILTIN)) ? + current_builtin->function : + (sh_builtin_func_t *)NULL); +} + +static int +shell_builtin_compare (sbp1, sbp2) + struct builtin *sbp1, *sbp2; +{ + int result; + + if ((result = sbp1->name[0] - sbp2->name[0]) == 0) + result = strcmp (sbp1->name, sbp2->name); + + return (result); +} + +/* Sort the table of shell builtins so that the binary search will work + in find_shell_builtin. */ +void +initialize_shell_builtins () +{ + qsort (shell_builtins, num_shell_builtins, sizeof (struct builtin), + (QSFUNC *)shell_builtin_compare); +} + +#if !defined (HELP_BUILTIN) +void +builtin_help () +{ + printf ("%s: %s\n", this_command_name, _("help not available in this version")); +} +#endif + +/* **************************************************************** */ +/* */ +/* Variable assignments during builtin commands */ +/* */ +/* **************************************************************** */ + +SHELL_VAR * +builtin_bind_variable (name, value, flags) + char *name; + char *value; + int flags; +{ + SHELL_VAR *v; + +#if defined (ARRAY_VARS) + if (valid_array_reference (name, assoc_expand_once ? (VA_NOEXPAND|VA_ONEWORD) : 0) == 0) + v = bind_variable (name, value, flags); + else + v = assign_array_element (name, value, flags | (assoc_expand_once ? ASS_NOEXPAND : 0)); +#else /* !ARRAY_VARS */ + v = bind_variable (name, value, flags); +#endif /* !ARRAY_VARS */ + + if (v && readonly_p (v) == 0 && noassign_p (v) == 0) + VUNSETATTR (v, att_invisible); + + return v; +} + +/* Like check_unbind_variable, but for use by builtins (only matters for + error messages). */ +int +builtin_unbind_variable (vname) + const char *vname; +{ + SHELL_VAR *v; + + v = find_variable (vname); + if (v && readonly_p (v)) + { + builtin_error (_("%s: cannot unset: readonly %s"), vname, "variable"); + return -2; + } + else if (v && non_unsettable_p (v)) + { + builtin_error (_("%s: cannot unset"), vname); + return -2; + } + return (unbind_variable (vname)); +} |