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Diffstat (limited to 'builtins/set.def')
| -rw-r--r-- | builtins/set.def | 1028 |
1 files changed, 1028 insertions, 0 deletions
diff --git a/builtins/set.def b/builtins/set.def new file mode 100644 index 0000000..44f1769 --- /dev/null +++ b/builtins/set.def @@ -0,0 +1,1028 @@ +This file is set.def, from which is created set.c. +It implements the "set" and "unset" builtins in Bash. + +Copyright (C) 1987-2021 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/>. + +$PRODUCES set.c + +#include <config.h> + +#if defined (HAVE_UNISTD_H) +# ifdef _MINIX +# include <sys/types.h> +# endif +# include <unistd.h> +#endif + +#include <stdio.h> + +#include "../bashansi.h" +#include "../bashintl.h" + +#include "../shell.h" +#include "../parser.h" +#include "../flags.h" +#include "common.h" +#include "bashgetopt.h" + +#if defined (READLINE) +# include "../input.h" +# include "../bashline.h" +# include <readline/readline.h> +#endif + +#if defined (HISTORY) +# include "../bashhist.h" +#endif + +$BUILTIN set +$FUNCTION set_builtin +$SHORT_DOC set [-abefhkmnptuvxBCEHPT] [-o option-name] [--] [-] [arg ...] +Set or unset values of shell options and positional parameters. + +Change the value of shell attributes and positional parameters, or +display the names and values of shell variables. + +Options: + -a Mark variables which are modified or created for export. + -b Notify of job termination immediately. + -e Exit immediately if a command exits with a non-zero status. + -f Disable file name generation (globbing). + -h Remember the location of commands as they are looked up. + -k All assignment arguments are placed in the environment for a + command, not just those that precede the command name. + -m Job control is enabled. + -n Read commands but do not execute them. + -o option-name + Set the variable corresponding to option-name: + allexport same as -a + braceexpand same as -B +#if defined (READLINE) + emacs use an emacs-style line editing interface +#endif /* READLINE */ + errexit same as -e + errtrace same as -E + functrace same as -T + hashall same as -h +#if defined (BANG_HISTORY) + histexpand same as -H +#endif /* BANG_HISTORY */ +#if defined (HISTORY) + history enable command history +#endif + ignoreeof the shell will not exit upon reading EOF + interactive-comments + allow comments to appear in interactive commands + keyword same as -k +#if defined (JOB_CONTROL) + monitor same as -m +#endif + noclobber same as -C + noexec same as -n + noglob same as -f + nolog currently accepted but ignored +#if defined (JOB_CONTROL) + notify same as -b +#endif + nounset same as -u + onecmd same as -t + physical same as -P + pipefail the return value of a pipeline is the status of + the last command to exit with a non-zero status, + or zero if no command exited with a non-zero status + posix change the behavior of bash where the default + operation differs from the Posix standard to + match the standard + privileged same as -p + verbose same as -v +#if defined (READLINE) + vi use a vi-style line editing interface +#endif /* READLINE */ + xtrace same as -x + -p Turned on whenever the real and effective user ids do not match. + Disables processing of the $ENV file and importing of shell + functions. Turning this option off causes the effective uid and + gid to be set to the real uid and gid. + -t Exit after reading and executing one command. + -u Treat unset variables as an error when substituting. + -v Print shell input lines as they are read. + -x Print commands and their arguments as they are executed. +#if defined (BRACE_EXPANSION) + -B the shell will perform brace expansion +#endif /* BRACE_EXPANSION */ + -C If set, disallow existing regular files to be overwritten + by redirection of output. + -E If set, the ERR trap is inherited by shell functions. +#if defined (BANG_HISTORY) + -H Enable ! style history substitution. This flag is on + by default when the shell is interactive. +#endif /* BANG_HISTORY */ + -P If set, do not resolve symbolic links when executing commands + such as cd which change the current directory. + -T If set, the DEBUG and RETURN traps are inherited by shell functions. + -- Assign any remaining arguments to the positional parameters. + If there are no remaining arguments, the positional parameters + are unset. + - Assign any remaining arguments to the positional parameters. + The -x and -v options are turned off. + +Using + rather than - causes these flags to be turned off. The +flags can also be used upon invocation of the shell. The current +set of flags may be found in $-. The remaining n ARGs are positional +parameters and are assigned, in order, to $1, $2, .. $n. If no +ARGs are given, all shell variables are printed. + +Exit Status: +Returns success unless an invalid option is given. +$END + +typedef int setopt_set_func_t PARAMS((int, char *)); +typedef int setopt_get_func_t PARAMS((char *)); + +static int find_minus_o_option PARAMS((char *)); + +static void print_minus_o_option PARAMS((char *, int, int)); +static void print_all_shell_variables PARAMS((void)); + +static int set_ignoreeof PARAMS((int, char *)); +static int set_posix_mode PARAMS((int, char *)); + +#if defined (READLINE) +static int set_edit_mode PARAMS((int, char *)); +static int get_edit_mode PARAMS((char *)); +#endif + +#if defined (HISTORY) +static int bash_set_history PARAMS((int, char *)); +#endif + +static const char * const on = "on"; +static const char * const off = "off"; + +static int previous_option_value; + +/* A struct used to match long options for set -o to the corresponding + option letter or internal variable. The functions can be called to + dynamically generate values. If you add a new variable name here + that doesn't have a corresponding single-character option letter, make + sure to set the value appropriately in reset_shell_options. */ +const struct { + char *name; + int letter; + int *variable; + setopt_set_func_t *set_func; + setopt_get_func_t *get_func; +} o_options[] = { + { "allexport", 'a', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#if defined (BRACE_EXPANSION) + { "braceexpand",'B', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#endif +#if defined (READLINE) + { "emacs", '\0', (int *)NULL, set_edit_mode, get_edit_mode }, +#endif + { "errexit", 'e', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "errtrace", 'E', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "functrace", 'T', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "hashall", 'h', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#if defined (BANG_HISTORY) + { "histexpand", 'H', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#endif /* BANG_HISTORY */ +#if defined (HISTORY) + { "history", '\0', &enable_history_list, bash_set_history, (setopt_get_func_t *)NULL }, +#endif + { "ignoreeof", '\0', &ignoreeof, set_ignoreeof, (setopt_get_func_t *)NULL }, + { "interactive-comments", '\0', &interactive_comments, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "keyword", 'k', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#if defined (JOB_CONTROL) + { "monitor", 'm', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#endif + { "noclobber", 'C', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "noexec", 'n', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "noglob", 'f', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#if defined (HISTORY) + { "nolog", '\0', &dont_save_function_defs, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#endif +#if defined (JOB_CONTROL) + { "notify", 'b', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#endif /* JOB_CONTROL */ + { "nounset", 'u', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "onecmd", 't', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "physical", 'P', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "pipefail", '\0', &pipefail_opt, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "posix", '\0', &posixly_correct, set_posix_mode, (setopt_get_func_t *)NULL }, + { "privileged", 'p', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + { "verbose", 'v', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +#if defined (READLINE) + { "vi", '\0', (int *)NULL, set_edit_mode, get_edit_mode }, +#endif + { "xtrace", 'x', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, + {(char *)NULL, 0 , (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL }, +}; + +#define N_O_OPTIONS (sizeof (o_options) / sizeof (o_options[0])) + +#define GET_BINARY_O_OPTION_VALUE(i, name) \ + ((o_options[i].get_func) ? (*o_options[i].get_func) (name) \ + : (*o_options[i].variable)) + +#define SET_BINARY_O_OPTION_VALUE(i, onoff, name) \ + ((o_options[i].set_func) ? (*o_options[i].set_func) (onoff, name) \ + : (*o_options[i].variable = (onoff == FLAG_ON))) + +static int +find_minus_o_option (name) + char *name; +{ + register int i; + + for (i = 0; o_options[i].name; i++) + if (STREQ (name, o_options[i].name)) + return i; + return -1; +} + +int +minus_o_option_value (name) + char *name; +{ + register int i; + int *on_or_off; + + i = find_minus_o_option (name); + if (i < 0) + return (-1); + + if (o_options[i].letter) + { + on_or_off = find_flag (o_options[i].letter); + return ((on_or_off == FLAG_UNKNOWN) ? -1 : *on_or_off); + } + else + return (GET_BINARY_O_OPTION_VALUE (i, name)); +} + +#define MINUS_O_FORMAT "%-15s\t%s\n" + +static void +print_minus_o_option (name, value, pflag) + char *name; + int value, pflag; +{ + if (pflag == 0) + printf (MINUS_O_FORMAT, name, value ? on : off); + else + printf ("set %co %s\n", value ? '-' : '+', name); +} + +void +list_minus_o_opts (mode, reusable) + int mode, reusable; +{ + register int i; + int *on_or_off, value; + + for (i = 0; o_options[i].name; i++) + { + if (o_options[i].letter) + { + value = 0; + on_or_off = find_flag (o_options[i].letter); + if (on_or_off == FLAG_UNKNOWN) + on_or_off = &value; + if (mode == -1 || mode == *on_or_off) + print_minus_o_option (o_options[i].name, *on_or_off, reusable); + } + else + { + value = GET_BINARY_O_OPTION_VALUE (i, o_options[i].name); + if (mode == -1 || mode == value) + print_minus_o_option (o_options[i].name, value, reusable); + } + } +} + +char ** +get_minus_o_opts () +{ + char **ret; + int i; + + ret = strvec_create (N_O_OPTIONS + 1); + for (i = 0; o_options[i].name; i++) + ret[i] = o_options[i].name; + ret[i] = (char *)NULL; + return ret; +} + +char * +get_current_options () +{ + char *temp; + int i, posixopts; + + posixopts = num_posix_options (); /* shopts modified by posix mode */ + /* Make the buffer big enough to hold the set -o options and the shopt + options modified by posix mode. */ + temp = (char *)xmalloc (1 + N_O_OPTIONS + posixopts); + for (i = 0; o_options[i].name; i++) + { + if (o_options[i].letter) + temp[i] = *(find_flag (o_options[i].letter)); + else + temp[i] = GET_BINARY_O_OPTION_VALUE (i, o_options[i].name); + } + + /* Add the shell options that are modified by posix mode to the end of the + bitmap. They will be handled in set_current_options() */ + get_posix_options (temp+i); + temp[i+posixopts] = '\0'; + return (temp); +} + +void +set_current_options (bitmap) + const char *bitmap; +{ + int i, v, cv, *on_or_off; + + if (bitmap == 0) + return; + + for (i = 0; o_options[i].name; i++) + { + v = bitmap[i] ? FLAG_ON : FLAG_OFF; + if (o_options[i].letter) + { + /* We should not get FLAG_UNKNOWN here */ + on_or_off = find_flag (o_options[i].letter); + cv = *on_or_off ? FLAG_ON : FLAG_OFF; + if (v != cv) + change_flag (o_options[i].letter, v); + } + else + { + cv = GET_BINARY_O_OPTION_VALUE (i, o_options[i].name); + cv = cv ? FLAG_ON : FLAG_OFF; + if (v != cv) + SET_BINARY_O_OPTION_VALUE (i, v, o_options[i].name); + } + } + + /* Now reset the variables changed by posix mode */ + set_posix_options (bitmap+i); +} + +static int +set_ignoreeof (on_or_off, option_name) + int on_or_off; + char *option_name; +{ + ignoreeof = on_or_off == FLAG_ON; + unbind_variable_noref ("ignoreeof"); + if (ignoreeof) + bind_variable ("IGNOREEOF", "10", 0); + else + unbind_variable_noref ("IGNOREEOF"); + sv_ignoreeof ("IGNOREEOF"); + return 0; +} + +static int +set_posix_mode (on_or_off, option_name) + int on_or_off; + char *option_name; +{ + /* short-circuit on no-op */ + if ((on_or_off == FLAG_ON && posixly_correct) || + (on_or_off == FLAG_OFF && posixly_correct == 0)) + return 0; + + posixly_correct = on_or_off == FLAG_ON; + if (posixly_correct == 0) + unbind_variable_noref ("POSIXLY_CORRECT"); + else + bind_variable ("POSIXLY_CORRECT", "y", 0); + sv_strict_posix ("POSIXLY_CORRECT"); + return (0); +} + +#if defined (READLINE) +/* Magic. This code `knows' how readline handles rl_editing_mode. */ +static int +set_edit_mode (on_or_off, option_name) + int on_or_off; + char *option_name; +{ + int isemacs; + + if (on_or_off == FLAG_ON) + { + rl_variable_bind ("editing-mode", option_name); + + if (interactive) + with_input_from_stdin (); + no_line_editing = 0; + } + else + { + isemacs = rl_editing_mode == 1; + if ((isemacs && *option_name == 'e') || (!isemacs && *option_name == 'v')) + { + if (interactive) + with_input_from_stream (stdin, "stdin"); + no_line_editing = 1; + } + } + return 1-no_line_editing; +} + +static int +get_edit_mode (name) + char *name; +{ + return (*name == 'e' ? no_line_editing == 0 && rl_editing_mode == 1 + : no_line_editing == 0 && rl_editing_mode == 0); +} +#endif /* READLINE */ + +#if defined (HISTORY) +static int +bash_set_history (on_or_off, option_name) + int on_or_off; + char *option_name; +{ + if (on_or_off == FLAG_ON) + { + enable_history_list = 1; + bash_history_enable (); + if (history_lines_this_session == 0) + load_history (); + } + else + { + enable_history_list = 0; + bash_history_disable (); + } + return (1 - enable_history_list); +} +#endif + +int +set_minus_o_option (on_or_off, option_name) + int on_or_off; + char *option_name; +{ + register int i; + + i = find_minus_o_option (option_name); + if (i < 0) + { + sh_invalidoptname (option_name); + return (EX_USAGE); + } + + if (o_options[i].letter == 0) + { + previous_option_value = GET_BINARY_O_OPTION_VALUE (i, o_options[i].name); + SET_BINARY_O_OPTION_VALUE (i, on_or_off, option_name); + return (EXECUTION_SUCCESS); + } + else + { + if ((previous_option_value = change_flag (o_options[i].letter, on_or_off)) == FLAG_ERROR) + { + sh_invalidoptname (option_name); + return (EXECUTION_FAILURE); + } + else + return (EXECUTION_SUCCESS); + } +} + +static void +print_all_shell_variables () +{ + SHELL_VAR **vars; + + vars = all_shell_variables (); + if (vars) + { + print_var_list (vars); + free (vars); + } + + /* POSIX.2 does not allow function names and definitions to be output when + `set' is invoked without options (PASC Interp #202). */ + if (posixly_correct == 0) + { + vars = all_shell_functions (); + if (vars) + { + print_func_list (vars); + free (vars); + } + } +} + +void +set_shellopts () +{ + char *value; + char tflag[N_O_OPTIONS]; + int vsize, i, vptr, *ip, exported; + SHELL_VAR *v; + + for (vsize = i = 0; o_options[i].name; i++) + { + tflag[i] = 0; + if (o_options[i].letter) + { + ip = find_flag (o_options[i].letter); + if (ip && *ip) + { + vsize += strlen (o_options[i].name) + 1; + tflag[i] = 1; + } + } + else if (GET_BINARY_O_OPTION_VALUE (i, o_options[i].name)) + { + vsize += strlen (o_options[i].name) + 1; + tflag[i] = 1; + } + } + + value = (char *)xmalloc (vsize + 1); + + for (i = vptr = 0; o_options[i].name; i++) + { + if (tflag[i]) + { + strcpy (value + vptr, o_options[i].name); + vptr += strlen (o_options[i].name); + value[vptr++] = ':'; + } + } + + if (vptr) + vptr--; /* cut off trailing colon */ + value[vptr] = '\0'; + + v = find_variable ("SHELLOPTS"); + + /* Turn off the read-only attribute so we can bind the new value, and + note whether or not the variable was exported. */ + if (v) + { + VUNSETATTR (v, att_readonly); + exported = exported_p (v); + } + else + exported = 0; + + v = bind_variable ("SHELLOPTS", value, 0); + + /* Turn the read-only attribute back on, and turn off the export attribute + if it was set implicitly by mark_modified_vars and SHELLOPTS was not + exported before we bound the new value. */ + VSETATTR (v, att_readonly); + if (mark_modified_vars && exported == 0 && exported_p (v)) + VUNSETATTR (v, att_exported); + + free (value); +} + +void +parse_shellopts (value) + char *value; +{ + char *vname; + int vptr; + + vptr = 0; + while (vname = extract_colon_unit (value, &vptr)) + { + set_minus_o_option (FLAG_ON, vname); + free (vname); + } +} + +void +initialize_shell_options (no_shellopts) + int no_shellopts; +{ + char *temp; + SHELL_VAR *var; + + if (no_shellopts == 0) + { + var = find_variable ("SHELLOPTS"); + /* set up any shell options we may have inherited. */ + if (var && imported_p (var)) + { + temp = (array_p (var) || assoc_p (var)) ? (char *)NULL : savestring (value_cell (var)); + if (temp) + { + parse_shellopts (temp); + free (temp); + } + } + } + + /* Set up the $SHELLOPTS variable. */ + set_shellopts (); +} + +/* Reset the values of the -o options that are not also shell flags. This is + called from execute_cmd.c:initialize_subshell() when setting up a subshell + to run an executable shell script without a leading `#!'. */ +void +reset_shell_options () +{ + pipefail_opt = 0; + ignoreeof = 0; + +#if defined (STRICT_POSIX) + posixly_correct = 1; +#else + posixly_correct = 0; +#endif +#if defined (HISTORY) + dont_save_function_defs = 0; + remember_on_history = enable_history_list = 1; /* XXX */ +#endif +} + +/* Set some flags from the word values in the input list. If LIST is empty, + then print out the values of the variables instead. If LIST contains + non-flags, then set $1 - $9 to the successive words of LIST. */ +int +set_builtin (list) + WORD_LIST *list; +{ + int on_or_off, flag_name, force_assignment, opts_changed, rv, r; + register char *arg; + char s[3]; + + if (list == 0) + { + print_all_shell_variables (); + return (sh_chkwrite (EXECUTION_SUCCESS)); + } + + /* Check validity of flag arguments. */ + rv = EXECUTION_SUCCESS; + reset_internal_getopt (); + while ((flag_name = internal_getopt (list, optflags)) != -1) + { + switch (flag_name) + { + case 'i': /* don't allow set -i */ + s[0] = list_opttype; + s[1] = 'i'; + s[2] = '\0'; + sh_invalidopt (s); + builtin_usage (); + return (EX_USAGE); + CASE_HELPOPT; + case '?': + builtin_usage (); + return (list_optopt == '?' ? EXECUTION_SUCCESS : EX_USAGE); + default: + break; + } + } + + /* Do the set command. While the list consists of words starting with + '-' or '+' treat them as flags, otherwise, start assigning them to + $1 ... $n. */ + for (force_assignment = opts_changed = 0; list; ) + { + arg = list->word->word; + + /* If the argument is `--' or `-' then signal the end of the list + and remember the remaining arguments. */ + if (arg[0] == '-' && (!arg[1] || (arg[1] == '-' && !arg[2]))) + { + list = list->next; + + /* `set --' unsets the positional parameters. */ + if (arg[1] == '-') + force_assignment = 1; + + /* Until told differently, the old shell behaviour of + `set - [arg ...]' being equivalent to `set +xv [arg ...]' + stands. Posix.2 says the behaviour is marked as obsolescent. */ + else + { + change_flag ('x', '+'); + change_flag ('v', '+'); + opts_changed = 1; + } + + break; + } + + if ((on_or_off = *arg) && (on_or_off == '-' || on_or_off == '+')) + { + while (flag_name = *++arg) + { + if (flag_name == '?') + { + builtin_usage (); + return (EXECUTION_SUCCESS); + } + else if (flag_name == 'o') /* -+o option-name */ + { + char *option_name; + WORD_LIST *opt; + + opt = list->next; + + if (opt == 0) + { + list_minus_o_opts (-1, (on_or_off == '+')); + rv = sh_chkwrite (rv); + continue; + } + + option_name = opt->word->word; + + if (option_name == 0 || *option_name == '\0' || + *option_name == '-' || *option_name == '+') + { + list_minus_o_opts (-1, (on_or_off == '+')); + continue; + } + list = list->next; /* Skip over option name. */ + + opts_changed = 1; + if ((r = set_minus_o_option (on_or_off, option_name)) != EXECUTION_SUCCESS) + { + set_shellopts (); + return (r); + } + } + else if (change_flag (flag_name, on_or_off) == FLAG_ERROR) + { + s[0] = on_or_off; + s[1] = flag_name; + s[2] = '\0'; + sh_invalidopt (s); + builtin_usage (); + set_shellopts (); + return (EXECUTION_FAILURE); + } + opts_changed = 1; + } + } + else + { + break; + } + list = list->next; + } + + /* Assigning $1 ... $n */ + if (list || force_assignment) + remember_args (list, 1); + /* Set up new value of $SHELLOPTS */ + if (opts_changed) + set_shellopts (); + return (rv); +} + +$BUILTIN unset +$FUNCTION unset_builtin +$SHORT_DOC unset [-f] [-v] [-n] [name ...] +Unset values and attributes of shell variables and functions. + +For each NAME, remove the corresponding variable or function. + +Options: + -f treat each NAME as a shell function + -v treat each NAME as a shell variable + -n treat each NAME as a name reference and unset the variable itself + rather than the variable it references + +Without options, unset first tries to unset a variable, and if that fails, +tries to unset a function. + +Some variables cannot be unset; also see `readonly'. + +Exit Status: +Returns success unless an invalid option is given or a NAME is read-only. +$END + +#define NEXT_VARIABLE() any_failed++; list = list->next; continue; + +int +unset_builtin (list) + WORD_LIST *list; +{ + int unset_function, unset_variable, unset_array, opt, nameref, any_failed; + int global_unset_func, global_unset_var, vflags, base_vflags, valid_id; + char *name, *tname; + + unset_function = unset_variable = unset_array = nameref = any_failed = 0; + global_unset_func = global_unset_var = 0; + + reset_internal_getopt (); + while ((opt = internal_getopt (list, "fnv")) != -1) + { + switch (opt) + { + case 'f': + global_unset_func = 1; + break; + case 'v': + global_unset_var = 1; + break; + case 'n': + nameref = 1; + break; + CASE_HELPOPT; + default: + builtin_usage (); + return (EX_USAGE); + } + } + + list = loptend; + + if (global_unset_func && global_unset_var) + { + builtin_error (_("cannot simultaneously unset a function and a variable")); + return (EXECUTION_FAILURE); + } + else if (unset_function && nameref) + nameref = 0; + +#if defined (ARRAY_VARS) + base_vflags = assoc_expand_once ? VA_NOEXPAND : 0; +#endif + + while (list) + { + SHELL_VAR *var; + int tem; +#if defined (ARRAY_VARS) + char *t; +#endif + + name = list->word->word; + + unset_function = global_unset_func; + unset_variable = global_unset_var; + +#if defined (ARRAY_VARS) + vflags = builtin_arrayref_flags (list->word, base_vflags); +#endif + +#if defined (ARRAY_VARS) + unset_array = 0; + /* XXX valid array reference second arg was 0 */ + if (!unset_function && nameref == 0 && tokenize_array_reference (name, vflags, &t)) + unset_array = 1; +#endif + /* Get error checking out of the way first. The low-level functions + just perform the unset, relying on the caller to verify. */ + valid_id = legal_identifier (name); + + /* Whether or not we are in posix mode, if neither -f nor -v appears, + skip over trying to unset variables with invalid names and just + treat them as potential shell function names. */ + if (global_unset_func == 0 && global_unset_var == 0 && valid_id == 0) + { + unset_variable = unset_array = 0; + unset_function = 1; + } + + /* Bash allows functions with names which are not valid identifiers + to be created when not in posix mode, so check only when in posix + mode when unsetting a function. */ + if (unset_function == 0 && valid_id == 0) + { + sh_invalidid (name); + NEXT_VARIABLE (); + } + + /* Search for functions here if -f supplied or if NAME cannot be a + variable name. */ + var = unset_function ? find_function (name) + : (nameref ? find_variable_last_nameref (name, 0) : find_variable (name)); + + /* Some variables (but not functions yet) cannot be unset, period. */ + if (var && unset_function == 0 && non_unsettable_p (var)) + { + builtin_error (_("%s: cannot unset"), name); + NEXT_VARIABLE (); + } + + /* if we have a nameref we want to use it */ + if (var && unset_function == 0 && nameref == 0 && STREQ (name, name_cell(var)) == 0) + name = name_cell (var); + + /* Posix.2 says try variables first, then functions. If we would + find a function after unsuccessfully searching for a variable, + note that we're acting on a function now as if -f were + supplied. The readonly check below takes care of it. */ + if (var == 0 && nameref == 0 && unset_variable == 0 && unset_function == 0) + { + if (var = find_function (name)) + unset_function = 1; + } + + /* Posix.2 says that unsetting readonly variables is an error. */ + if (var && readonly_p (var)) + { + builtin_error (_("%s: cannot unset: readonly %s"), + var->name, unset_function ? "function" : "variable"); + NEXT_VARIABLE (); + } + + /* Unless the -f option is supplied, the name refers to a variable. */ +#if defined (ARRAY_VARS) + if (var && unset_array) + { + if (shell_compatibility_level <= 51) + vflags |= VA_ALLOWALL; + + /* Let unbind_array_element decide what to do with non-array vars */ + tem = unbind_array_element (var, t, vflags); /* XXX new third arg */ + if (tem == -2 && array_p (var) == 0 && assoc_p (var) == 0) + { + builtin_error (_("%s: not an array variable"), var->name); + NEXT_VARIABLE (); + } + else if (tem < 0) + any_failed++; + } + else +#endif /* ARRAY_VARS */ + /* If we're trying to unset a nameref variable whose value isn't a set + variable, make sure we still try to unset the nameref's value */ + if (var == 0 && nameref == 0 && unset_function == 0) + { + var = find_variable_last_nameref (name, 0); + if (var && nameref_p (var)) + { +#if defined (ARRAY_VARS) + if (valid_array_reference (nameref_cell (var), 0)) + { + int len; + + tname = savestring (nameref_cell (var)); + if (var = array_variable_part (tname, 0, &t, &len)) + { + /* change to what unbind_array_element now expects */ + if (t[len - 1] == ']') + t[len - 1] = 0; + tem = unbind_array_element (var, t, vflags); /* XXX new third arg */ + } + free (tname); + } + else +#endif + tem = unbind_variable (nameref_cell (var)); + } + else + tem = unbind_variable (name); + } + else + tem = unset_function ? unbind_func (name) : (nameref ? unbind_nameref (name) : unbind_variable (name)); + + /* This is what Posix.2 says: ``If neither -f nor -v + is specified, the name refers to a variable; if a variable by + that name does not exist, a function by that name, if any, + shall be unset.'' */ + if (tem == -1 && nameref == 0 && unset_function == 0 && unset_variable == 0) + tem = unbind_func (name); + + name = list->word->word; /* reset above for namerefs */ + + /* SUSv3, POSIX.1-2001 say: ``Unsetting a variable or function that + was not previously set shall not be considered an error.'' */ + + if (unset_function == 0) + stupidly_hack_special_variables (name); + + list = list->next; + } + + return (any_failed ? EXECUTION_FAILURE : EXECUTION_SUCCESS); +} |