1 /* shell.c -- GNU's idea of the POSIX shell specification. */
3 /* Copyright (C) 1987-2012 Free Software Foundation, Inc.
5 This file is part of GNU Bash, the Bourne Again SHell.
7 Bash is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 Bash is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with Bash. If not, see <http://www.gnu.org/licenses/>.
23 Sunday, January 10th, 1988.
24 Initial author: Brian Fox
26 #define INSTALL_DEBUG_MODE
30 #include "bashtypes.h"
31 #if !defined (_MINIX) && defined (HAVE_SYS_FILE_H)
32 # include <sys/file.h>
34 #include "posixstat.h"
35 #include "posixtime.h"
43 #if defined (HAVE_UNISTD_H)
49 #define NEED_SH_SETLINEBUF_DECL /* used in externs.h */
54 #include "mailcheck.h"
56 #include "builtins/common.h"
58 #if defined (JOB_CONTROL)
60 #endif /* JOB_CONTROL */
63 #include "execute_cmd.h"
66 #if defined (USING_BASH_MALLOC) && defined (DEBUG) && !defined (DISABLE_MALLOC_WRAPPERS)
67 # include <malloc/shmalloc.h>
71 # include "bashhist.h"
72 # include <readline/history.h>
75 #if defined (READLINE)
76 # include "bashline.h"
79 #include <tilde/tilde.h>
80 #include <glob/strmatch.h>
82 #if defined (__OPENNT)
83 # include <opennt/opennt.h>
86 #if !defined (HAVE_GETPW_DECLS)
87 extern struct passwd *getpwuid ();
88 #endif /* !HAVE_GETPW_DECLS */
94 #if defined (NO_MAIN_ENV_ARG)
95 extern char **environ; /* used if no third argument to main() */
98 extern char *dist_version, *release_status;
99 extern int patch_level, build_version;
100 extern int shell_level;
101 extern int subshell_environment;
102 extern int last_command_exit_value;
103 extern int line_number;
104 extern int expand_aliases;
105 extern int array_needs_making;
106 extern int gnu_error_format;
107 extern char *primary_prompt, *secondary_prompt;
108 extern char *this_command_name;
110 /* Non-zero means that this shell has already been run; i.e. you should
111 call shell_reinitialize () if you need to start afresh. */
112 int shell_initialized = 0;
114 COMMAND *global_command = (COMMAND *)NULL;
116 /* Information about the current user. */
117 struct user_info current_user =
119 (uid_t)-1, (uid_t)-1, (gid_t)-1, (gid_t)-1,
120 (char *)NULL, (char *)NULL, (char *)NULL
123 /* The current host's name. */
124 char *current_host_name = (char *)NULL;
126 /* Non-zero means that this shell is a login shell.
129 1 = login shell from getty (or equivalent fake out)
130 -1 = login shell from "--login" (or -l) flag.
131 -2 = both from getty, and from flag.
135 /* Non-zero means that at this moment, the shell is interactive. In
136 general, this means that the shell is at this moment reading input
137 from the keyboard. */
140 /* Non-zero means that the shell was started as an interactive shell. */
141 int interactive_shell = 0;
143 /* Non-zero means to send a SIGHUP to all jobs when an interactive login
147 /* Non-zero means to list status of running and stopped jobs at shell exit */
148 int check_jobs_at_exit = 0;
150 /* Non-zero means to change to a directory name supplied as a command name */
153 /* Tells what state the shell was in when it started:
154 0 = non-interactive shell script
157 3 = wordexp evaluation
158 This is a superset of the information provided by interactive_shell.
160 int startup_state = 0;
162 /* Special debugging helper. */
163 int debugging_login_shell = 0;
165 /* The environment that the shell passes to other commands. */
166 char **shell_environment;
168 /* Non-zero when we are executing a top-level command. */
171 /* The number of commands executed so far. */
172 int current_command_number = 1;
174 /* Non-zero is the recursion depth for commands. */
175 int indirection_level = 0;
177 /* The name of this shell, as taken from argv[0]. */
178 char *shell_name = (char *)NULL;
180 /* time in seconds when the shell was started */
181 time_t shell_start_time;
183 /* Are we running in an emacs shell window? */
184 int running_under_emacs;
186 /* Do we have /dev/fd? */
188 int have_devfd = HAVE_DEV_FD;
193 /* The name of the .(shell)rc file. */
194 static char *bashrc_file = "~/.bashrc";
196 /* Non-zero means to act more like the Bourne shell on startup. */
197 static int act_like_sh;
199 /* Non-zero if this shell is being run by `su'. */
202 /* Non-zero if we have already expanded and sourced $ENV. */
203 static int sourced_env;
205 /* Is this shell running setuid? */
206 static int running_setuid;
208 /* Values for the long-winded argument names. */
209 static int debugging; /* Do debugging things. */
210 static int no_rc; /* Don't execute ~/.bashrc */
211 static int no_profile; /* Don't execute .profile */
212 static int do_version; /* Display interesting version info. */
213 static int make_login_shell; /* Make this shell be a `-bash' shell. */
214 static int want_initial_help; /* --help option */
216 int debugging_mode = 0; /* In debugging mode with --debugger */
217 #if defined (READLINE)
218 int no_line_editing = 0; /* non-zero -> don't do fancy line editing. */
220 int no_line_editing = 1; /* can't have line editing without readline */
222 int dump_translatable_strings; /* Dump strings in $"...", don't execute. */
223 int dump_po_strings; /* Dump strings in $"..." in po format */
224 int wordexp_only = 0; /* Do word expansion only */
225 int protected_mode = 0; /* No command substitution with --wordexp */
227 #if defined (STRICT_POSIX)
228 int posixly_correct = 1; /* Non-zero means posix.2 superset. */
230 int posixly_correct = 0; /* Non-zero means posix.2 superset. */
233 /* Some long-winded argument names. These are obviously new. */
236 static const struct {
242 { "debug", Int, &debugging, (char **)0x0 },
243 #if defined (DEBUGGER)
244 { "debugger", Int, &debugging_mode, (char **)0x0 },
246 { "dump-po-strings", Int, &dump_po_strings, (char **)0x0 },
247 { "dump-strings", Int, &dump_translatable_strings, (char **)0x0 },
248 { "help", Int, &want_initial_help, (char **)0x0 },
249 { "init-file", Charp, (int *)0x0, &bashrc_file },
250 { "login", Int, &make_login_shell, (char **)0x0 },
251 { "noediting", Int, &no_line_editing, (char **)0x0 },
252 { "noprofile", Int, &no_profile, (char **)0x0 },
253 { "norc", Int, &no_rc, (char **)0x0 },
254 { "posix", Int, &posixly_correct, (char **)0x0 },
255 #if defined (WORDEXP_OPTION)
256 { "protected", Int, &protected_mode, (char **)0x0 },
258 { "rcfile", Charp, (int *)0x0, &bashrc_file },
259 #if defined (RESTRICTED_SHELL)
260 { "restricted", Int, &restricted, (char **)0x0 },
262 { "verbose", Int, &echo_input_at_read, (char **)0x0 },
263 { "version", Int, &do_version, (char **)0x0 },
264 #if defined (WORDEXP_OPTION)
265 { "wordexp", Int, &wordexp_only, (char **)0x0 },
267 { (char *)0x0, Int, (int *)0x0, (char **)0x0 }
270 /* These are extern so execute_simple_command can set them, and then
271 longjmp back to main to execute a shell script, instead of calling
272 main () again and resulting in indefinite, possibly fatal, stack
274 procenv_t subshell_top_level;
276 char **subshell_argv;
277 char **subshell_envp;
281 #if defined (BUFFERED_INPUT)
282 /* The file descriptor from which the shell is reading input. */
283 int default_buffered_input = -1;
286 /* The following two variables are not static so they can show up in $-. */
287 int read_from_stdin; /* -s flag supplied */
288 int want_pending_command; /* -c flag supplied */
290 /* This variable is not static so it can be bound to $BASH_EXECUTION_STRING */
291 char *command_execution_string; /* argument to -c option */
293 int malloc_trace_at_exit = 0;
295 static int shell_reinitialized = 0;
297 static FILE *default_input;
299 static STRING_INT_ALIST *shopt_alist;
300 static int shopt_ind = 0, shopt_len = 0;
302 static int parse_long_options __P((char **, int, int));
303 static int parse_shell_options __P((char **, int, int));
304 static int bind_args __P((char **, int, int, int));
306 static void start_debugger __P((void));
308 static void add_shopt_to_alist __P((char *, int));
309 static void run_shopt_alist __P((void));
311 static void execute_env_file __P((char *));
312 static void run_startup_files __P((void));
313 static int open_shell_script __P((char *));
314 static void set_bash_input __P((void));
315 static int run_one_command __P((char *));
316 #if defined (WORDEXP_OPTION)
317 static int run_wordexp __P((char *));
320 static int uidget __P((void));
322 static void init_interactive __P((void));
323 static void init_noninteractive __P((void));
324 static void init_interactive_script __P((void));
326 static void set_shell_name __P((char *));
327 static void shell_initialize __P((void));
328 static void shell_reinitialize __P((void));
330 static void show_shell_usage __P((FILE *, int));
334 _cygwin32_check_tmp ()
338 if (stat ("/tmp", &sb) < 0)
339 internal_warning (_("could not find /tmp, please create!"));
342 if (S_ISDIR (sb.st_mode) == 0)
343 internal_warning (_("/tmp must be a valid directory name"));
346 #endif /* __CYGWIN__ */
348 #if defined (NO_MAIN_ENV_ARG)
349 /* systems without third argument to main() */
354 #else /* !NO_MAIN_ENV_ARG */
356 main (argc, argv, env)
359 #endif /* !NO_MAIN_ENV_ARG */
362 int code, old_errexit_flag;
363 #if defined (RESTRICTED_SHELL)
366 volatile int locally_skip_execution;
367 volatile int arg_index, top_level_arg_index;
372 #endif /* __OPENNT */
378 USE_VAR(old_errexit_flag);
379 #if defined (RESTRICTED_SHELL)
383 /* Catch early SIGINTs. */
384 code = setjmp_nosigs (top_level);
390 #if defined (USING_BASH_MALLOC) && defined (DEBUG) && !defined (DISABLE_MALLOC_WRAPPERS)
392 malloc_set_register (1);
399 _cygwin32_check_tmp ();
400 #endif /* __CYGWIN__ */
402 /* Wait forever if we are debugging a login shell. */
403 while (debugging_login_shell) sleep (3);
405 set_default_locale ();
407 running_setuid = uidget ();
409 if (getenv ("POSIXLY_CORRECT") || getenv ("POSIX_PEDANTIC"))
412 #if defined (USE_GNU_MALLOC_LIBRARY)
413 mcheck (programming_error, (void (*) ())0);
414 #endif /* USE_GNU_MALLOC_LIBRARY */
416 if (setjmp (subshell_top_level))
418 argc = subshell_argc;
419 argv = subshell_argv;
424 shell_reinitialized = 0;
426 /* Initialize `local' variables for all `invocations' of main (). */
428 if (arg_index > argc)
430 command_execution_string = (char *)NULL;
431 want_pending_command = locally_skip_execution = read_from_stdin = 0;
432 default_input = stdin;
433 #if defined (BUFFERED_INPUT)
434 default_buffered_input = -1;
437 /* Fix for the `infinite process creation' bug when running shell scripts
438 from startup files on System V. */
439 login_shell = make_login_shell = 0;
441 /* If this shell has already been run, then reinitialize it to a
443 if (shell_initialized || shell_name)
445 /* Make sure that we do not infinitely recurse as a login shell. */
446 if (*shell_name == '-')
449 shell_reinitialize ();
450 if (setjmp_nosigs (top_level))
454 shell_environment = env;
455 set_shell_name (argv[0]);
456 shell_start_time = NOW; /* NOW now defined in general.h */
458 /* Parse argument flags from the input line. */
460 /* Find full word arguments first. */
461 arg_index = parse_long_options (argv, arg_index, argc);
463 if (want_initial_help)
465 show_shell_usage (stdout, 1);
466 exit (EXECUTION_SUCCESS);
471 show_shell_version (1);
472 exit (EXECUTION_SUCCESS);
475 /* All done with full word options; do standard shell option parsing.*/
476 this_command_name = shell_name; /* for error reporting */
477 arg_index = parse_shell_options (argv, arg_index, argc);
479 /* If user supplied the "--login" (or -l) flag, then set and invert
481 if (make_login_shell)
484 login_shell = -login_shell;
487 set_login_shell ("login_shell", login_shell != 0);
490 dump_translatable_strings = 1;
492 if (dump_translatable_strings)
493 read_but_dont_execute = 1;
495 if (running_setuid && privileged_mode == 0)
496 disable_priv_mode ();
498 /* Need to get the argument to a -c option processed in the
499 above loop. The next arg is a command to execute, and the
500 following args are $0...$n respectively. */
501 if (want_pending_command)
503 command_execution_string = argv[arg_index];
504 if (command_execution_string == 0)
506 report_error (_("%s: option requires an argument"), "-c");
511 this_command_name = (char *)NULL;
513 cmd_init(); /* initialize the command object caches */
515 /* First, let the outside world know about our interactive status.
516 A shell is interactive if the `-i' flag was given, or if all of
517 the following conditions are met:
519 no arguments remaining or the -s flag given
520 standard input is a terminal
521 standard error is a terminal
522 Refer to Posix.2, the description of the `sh' utility. */
524 if (forced_interactive || /* -i flag */
525 (!command_execution_string && /* No -c command and ... */
526 wordexp_only == 0 && /* No --wordexp and ... */
527 ((arg_index == argc) || /* no remaining args or... */
528 read_from_stdin) && /* -s flag with args, and */
529 isatty (fileno (stdin)) && /* Input is a terminal and */
530 isatty (fileno (stderr)))) /* error output is a terminal. */
533 init_noninteractive ();
536 * Some systems have the bad habit of starting login shells with lots of open
537 * file descriptors. For instance, most systems that have picked up the
538 * pre-4.0 Sun YP code leave a file descriptor open each time you call one
539 * of the getpw* functions, and it's set to be open across execs. That
540 * means one for login, one for xterm, one for shelltool, etc. There are
541 * also systems that open persistent FDs to other agents or files as part
542 * of process startup; these need to be set to be close-on-exec.
544 if (login_shell && interactive_shell)
546 for (i = 3; i < 20; i++)
547 SET_CLOSE_ON_EXEC (i);
550 /* If we're in a strict Posix.2 mode, turn on interactive comments,
551 alias expansion in non-interactive shells, and other Posix.2 things. */
554 bind_variable ("POSIXLY_CORRECT", "y", 0);
555 sv_strict_posix ("POSIXLY_CORRECT");
558 /* Now we run the shopt_alist and process the options. */
562 /* From here on in, the shell must be a normal functioning shell.
563 Variables from the environment are expected to be set, etc. */
567 set_default_locale_vars ();
570 * M-x term -> TERM=eterm EMACS=22.1 (term:0.96) (eterm)
571 * M-x shell -> TERM=dumb EMACS=t (no line editing)
572 * M-x terminal -> TERM=emacs-em7955 EMACS= (line editing)
574 if (interactive_shell)
578 term = get_string_value ("TERM");
579 emacs = get_string_value ("EMACS");
581 /* Not sure any emacs terminal emulator sets TERM=emacs any more */
582 no_line_editing |= term && (STREQ (term, "emacs"));
583 no_line_editing |= emacs && emacs[0] == 't' && emacs[1] == '\0' && STREQ (term, "dumb");
585 /* running_under_emacs == 2 for `eterm' */
586 running_under_emacs = (emacs != 0) || (term && STREQN (term, "emacs", 5));
587 running_under_emacs += term && STREQN (term, "eterm", 5) && emacs && strstr (emacs, "term");
589 if (running_under_emacs)
590 gnu_error_format = 1;
593 top_level_arg_index = arg_index;
594 old_errexit_flag = exit_immediately_on_error;
596 /* Give this shell a place to longjmp to before executing the
597 startup files. This allows users to press C-c to abort the
599 code = setjmp (top_level);
602 if (code == EXITPROG || code == ERREXIT)
603 exit_shell (last_command_exit_value);
606 #if defined (JOB_CONTROL)
607 /* Reset job control, since run_startup_files turned it off. */
608 set_job_control (interactive_shell);
610 /* Reset value of `set -e', since it's turned off before running
611 the startup files. */
612 exit_immediately_on_error += old_errexit_flag;
613 locally_skip_execution++;
617 arg_index = top_level_arg_index;
619 /* Execute the start-up scripts. */
621 if (interactive_shell == 0)
623 unbind_variable ("PS1");
624 unbind_variable ("PS2");
627 /* This has already been done by init_noninteractive */
628 expand_aliases = posixly_correct;
633 change_flag ('i', FLAG_ON);
637 #if defined (RESTRICTED_SHELL)
638 /* Set restricted_shell based on whether the basename of $0 indicates that
639 the shell should be restricted or if the `-r' option was supplied at
641 restricted_shell = shell_is_restricted (shell_name);
643 /* If the `-r' option is supplied at invocation, make sure that the shell
644 is not in restricted mode when running the startup files. */
645 saverst = restricted;
649 /* The startup files are run with `set -e' temporarily disabled. */
650 if (locally_skip_execution == 0 && running_setuid == 0)
652 old_errexit_flag = exit_immediately_on_error;
653 exit_immediately_on_error = 0;
655 run_startup_files ();
656 exit_immediately_on_error += old_errexit_flag;
659 /* If we are invoked as `sh', turn on Posix mode. */
662 bind_variable ("POSIXLY_CORRECT", "y", 0);
663 sv_strict_posix ("POSIXLY_CORRECT");
666 #if defined (RESTRICTED_SHELL)
667 /* Turn on the restrictions after executing the startup files. This
668 means that `bash -r' or `set -r' invoked from a startup file will
669 turn on the restrictions after the startup files are executed. */
670 restricted = saverst || restricted;
671 if (shell_reinitialized == 0)
672 maybe_make_restricted (shell_name);
673 #endif /* RESTRICTED_SHELL */
675 #if defined (WORDEXP_OPTION)
679 last_command_exit_value = run_wordexp (argv[arg_index]);
680 exit_shell (last_command_exit_value);
684 if (command_execution_string)
686 arg_index = bind_args (argv, arg_index, argc, 0);
692 #if defined (ONESHOT)
694 run_one_command (command_execution_string);
695 exit_shell (last_command_exit_value);
697 with_input_from_string (command_execution_string, "-c");
698 goto read_and_execute;
699 #endif /* !ONESHOT */
702 /* Get possible input filename and set up default_buffered_input or
703 default_input as appropriate. */
704 if (arg_index != argc && read_from_stdin == 0)
706 open_shell_script (argv[arg_index]);
709 else if (interactive == 0)
710 /* In this mode, bash is reading a script from stdin, which is a
711 pipe or redirected file. */
712 #if defined (BUFFERED_INPUT)
713 default_buffered_input = fileno (stdin); /* == 0 */
715 setbuf (default_input, (char *)NULL);
716 #endif /* !BUFFERED_INPUT */
720 /* Bind remaining args to $1 ... $n */
721 arg_index = bind_args (argv, arg_index, argc, 1);
723 if (debugging_mode && locally_skip_execution == 0 && running_setuid == 0 && dollar_vars[1])
726 /* Do the things that should be done only for interactive shells. */
727 if (interactive_shell)
729 /* Set up for checking for presence of mail. */
733 #if defined (HISTORY)
734 /* Initialize the interactive history stuff. */
735 bash_initialize_history ();
736 /* Don't load the history from the history file if we've already
737 saved some lines in this session (e.g., by putting `history -s xx'
738 into one of the startup files). */
739 if (shell_initialized == 0 && history_lines_this_session == 0)
743 /* Initialize terminal state for interactive shells after the
744 .bash_profile and .bashrc are interpreted. */
748 #if !defined (ONESHOT)
750 #endif /* !ONESHOT */
752 shell_initialized = 1;
754 /* Read commands until exit condition. */
756 exit_shell (last_command_exit_value);
760 parse_long_options (argv, arg_start, arg_end)
762 int arg_start, arg_end;
764 int arg_index, longarg, i;
767 arg_index = arg_start;
768 while ((arg_index != arg_end) && (arg_string = argv[arg_index]) &&
769 (*arg_string == '-'))
773 /* Make --login equivalent to -login. */
774 if (arg_string[1] == '-' && arg_string[2])
780 for (i = 0; long_args[i].name; i++)
782 if (STREQ (arg_string + 1, long_args[i].name))
784 if (long_args[i].type == Int)
785 *long_args[i].int_value = 1;
786 else if (argv[++arg_index] == 0)
788 report_error (_("%s: option requires an argument"), long_args[i].name);
792 *long_args[i].char_value = argv[arg_index];
797 if (long_args[i].name == 0)
801 report_error (_("%s: invalid option"), argv[arg_index]);
802 show_shell_usage (stderr, 0);
805 break; /* No such argument. Maybe flag arg. */
815 parse_shell_options (argv, arg_start, arg_end)
817 int arg_start, arg_end;
820 int arg_character, on_or_off, next_arg, i;
821 char *o_option, *arg_string;
823 arg_index = arg_start;
824 while (arg_index != arg_end && (arg_string = argv[arg_index]) &&
825 (*arg_string == '-' || *arg_string == '+'))
827 /* There are flag arguments, so parse them. */
828 next_arg = arg_index + 1;
830 /* A single `-' signals the end of options. From the 4.3 BSD sh.
831 An option `--' means the same thing; this is the standard
832 getopt(3) meaning. */
833 if (arg_string[0] == '-' &&
834 (arg_string[1] == '\0' ||
835 (arg_string[1] == '-' && arg_string[2] == '\0')))
839 on_or_off = arg_string[0];
840 while (arg_character = arg_string[i++])
842 switch (arg_character)
845 want_pending_command = 1;
849 make_login_shell = 1;
857 o_option = argv[next_arg];
860 list_minus_o_opts (-1, (on_or_off == '-') ? 0 : 1);
863 if (set_minus_o_option (on_or_off, o_option) != EXECUTION_SUCCESS)
869 /* Since some of these can be overridden by the normal
870 interactive/non-interactive shell initialization or
871 initializing posix mode, we save the options and process
872 them after initialization. */
873 o_option = argv[next_arg];
876 shopt_listopt (o_option, (on_or_off == '-') ? 0 : 1);
879 add_shopt_to_alist (o_option, on_or_off);
884 dump_translatable_strings = 1;
888 if (change_flag (arg_character, on_or_off) == FLAG_ERROR)
890 report_error (_("%c%c: invalid option"), on_or_off, arg_character);
891 show_shell_usage (stderr, 0);
896 /* Can't do just a simple increment anymore -- what about
897 "bash -abouo emacs ignoreeof -hP"? */
898 arg_index = next_arg;
904 /* Exit the shell with status S. */
909 fflush (stdout); /* XXX */
912 /* Do trap[0] if defined. Allow it to override the exit status
914 if (signal_is_trapped (0))
915 s = run_exit_trap ();
917 #if defined (PROCESS_SUBSTITUTION)
919 #endif /* PROCESS_SUBSTITUTION */
921 #if defined (HISTORY)
922 if (remember_on_history)
923 maybe_save_shell_history ();
926 #if defined (COPROCESS_SUPPORT)
930 #if defined (JOB_CONTROL)
931 /* If the user has run `shopt -s huponexit', hangup all jobs when we exit
932 an interactive login shell. ksh does this unconditionally. */
933 if (interactive_shell && login_shell && hup_on_exit)
936 /* If this shell is interactive, terminate all stopped jobs and
937 restore the original terminal process group. Don't do this if we're
938 in a subshell and calling exit_shell after, for example, a failed
940 if (subshell_environment == 0)
942 #endif /* JOB_CONTROL */
944 /* Always return the exit status of the last command to our parent. */
948 /* A wrapper for exit that (optionally) can do other things, like malloc
949 statistics tracing. */
954 #if defined (MALLOC_DEBUG) && defined (USING_BASH_MALLOC)
955 if (malloc_trace_at_exit)
956 trace_malloc_stats (get_name_for_error (), (char *)NULL);
962 /* Exit a subshell, which includes calling the exit trap. We don't want to
963 do any more cleanup, since a subshell is created as an exact copy of its
972 /* Do trap[0] if defined. Allow it to override the exit status
974 if (signal_is_trapped (0))
975 s = run_exit_trap ();
980 /* Source the bash startup files. If POSIXLY_CORRECT is non-zero, we obey
981 the Posix.2 startup file rules: $ENV is expanded, and if the file it
982 names exists, that file is sourced. The Posix.2 rules are in effect
983 for interactive shells only. (section 4.56.5.3) */
985 /* Execute ~/.bashrc for most shells. Never execute it if
986 ACT_LIKE_SH is set, or if NO_RC is set.
988 If the executable file "/usr/gnu/src/bash/foo" contains:
995 COMMAND EXECUTE BASHRC
996 --------------------------------
1000 rsh machine ls YES (for rsh, which calls `bash -c')
1001 rsh machine foo YES (for shell started by rsh) NO (for foo!)
1008 execute_env_file (env_file)
1013 if (env_file && *env_file)
1015 fn = expand_string_unsplit_to_string (env_file, Q_DOUBLE_QUOTES);
1017 maybe_execute_file (fn, 1);
1023 run_startup_files ()
1025 #if defined (JOB_CONTROL)
1026 int old_job_control;
1028 int sourced_login, run_by_ssh;
1030 /* get the rshd/sshd case out of the way first. */
1031 if (interactive_shell == 0 && no_rc == 0 && login_shell == 0 &&
1032 act_like_sh == 0 && command_execution_string)
1034 #ifdef SSH_SOURCE_BASHRC
1035 run_by_ssh = (find_variable ("SSH_CLIENT") != (SHELL_VAR *)0) ||
1036 (find_variable ("SSH2_CLIENT") != (SHELL_VAR *)0);
1041 /* If we were run by sshd or we think we were run by rshd, execute
1042 ~/.bashrc if we are a top-level shell. */
1043 if ((run_by_ssh || isnetconn (fileno (stdin))) && shell_level < 2)
1046 # if defined (__OPENNT)
1047 maybe_execute_file (_prefixInstallPath(SYS_BASHRC, NULL, 0), 1);
1049 maybe_execute_file (SYS_BASHRC, 1);
1052 maybe_execute_file (bashrc_file, 1);
1057 #if defined (JOB_CONTROL)
1058 /* Startup files should be run without job control enabled. */
1059 old_job_control = interactive_shell ? set_job_control (0) : 0;
1064 /* A shell begun with the --login (or -l) flag that is not in posix mode
1065 runs the login shell startup files, no matter whether or not it is
1066 interactive. If NON_INTERACTIVE_LOGIN_SHELLS is defined, run the
1067 startup files if argv[0][0] == '-' as well. */
1068 #if defined (NON_INTERACTIVE_LOGIN_SHELLS)
1069 if (login_shell && posixly_correct == 0)
1071 if (login_shell < 0 && posixly_correct == 0)
1074 /* We don't execute .bashrc for login shells. */
1077 /* Execute /etc/profile and one of the personal login shell
1078 initialization files. */
1079 if (no_profile == 0)
1081 maybe_execute_file (SYS_PROFILE, 1);
1083 if (act_like_sh) /* sh */
1084 maybe_execute_file ("~/.profile", 1);
1085 else if ((maybe_execute_file ("~/.bash_profile", 1) == 0) &&
1086 (maybe_execute_file ("~/.bash_login", 1) == 0)) /* bash */
1087 maybe_execute_file ("~/.profile", 1);
1093 /* A non-interactive shell not named `sh' and not in posix mode reads and
1094 executes commands from $BASH_ENV. If `su' starts a shell with `-c cmd'
1095 and `-su' as the name of the shell, we want to read the startup files.
1096 No other non-interactive shells read any startup files. */
1097 if (interactive_shell == 0 && !(su_shell && login_shell))
1099 if (posixly_correct == 0 && act_like_sh == 0 && privileged_mode == 0 &&
1101 execute_env_file (get_string_value ("BASH_ENV"));
1105 /* Interactive shell or `-su' shell. */
1106 if (posixly_correct == 0) /* bash, sh */
1108 if (login_shell && sourced_login++ == 0)
1110 /* We don't execute .bashrc for login shells. */
1113 /* Execute /etc/profile and one of the personal login shell
1114 initialization files. */
1115 if (no_profile == 0)
1117 maybe_execute_file (SYS_PROFILE, 1);
1119 if (act_like_sh) /* sh */
1120 maybe_execute_file ("~/.profile", 1);
1121 else if ((maybe_execute_file ("~/.bash_profile", 1) == 0) &&
1122 (maybe_execute_file ("~/.bash_login", 1) == 0)) /* bash */
1123 maybe_execute_file ("~/.profile", 1);
1128 if (act_like_sh == 0 && no_rc == 0)
1131 # if defined (__OPENNT)
1132 maybe_execute_file (_prefixInstallPath(SYS_BASHRC, NULL, 0), 1);
1134 maybe_execute_file (SYS_BASHRC, 1);
1137 maybe_execute_file (bashrc_file, 1);
1140 else if (act_like_sh && privileged_mode == 0 && sourced_env++ == 0)
1141 execute_env_file (get_string_value ("ENV"));
1143 else /* bash --posix, sh --posix */
1146 if (interactive_shell && privileged_mode == 0 && sourced_env++ == 0)
1147 execute_env_file (get_string_value ("ENV"));
1150 #if defined (JOB_CONTROL)
1151 set_job_control (old_job_control);
1155 #if defined (RESTRICTED_SHELL)
1156 /* Return 1 if the shell should be a restricted one based on NAME or the
1157 value of `restricted'. Don't actually do anything, just return a
1160 shell_is_restricted (name)
1167 temp = base_pathname (name);
1170 return (STREQ (temp, RESTRICTED_SHELL_NAME));
1173 /* Perhaps make this shell a `restricted' one, based on NAME. If the
1174 basename of NAME is "rbash", then this shell is restricted. The
1175 name of the restricted shell is a configurable option, see config.h.
1176 In a restricted shell, PATH, SHELL, ENV, and BASH_ENV are read-only
1178 Do this also if `restricted' is already set to 1; maybe the shell was
1181 maybe_make_restricted (name)
1186 temp = base_pathname (name);
1189 if (restricted || (STREQ (temp, RESTRICTED_SHELL_NAME)))
1191 set_var_read_only ("PATH");
1192 set_var_read_only ("SHELL");
1193 set_var_read_only ("ENV");
1194 set_var_read_only ("BASH_ENV");
1197 return (restricted);
1199 #endif /* RESTRICTED_SHELL */
1201 /* Fetch the current set of uids and gids and return 1 if we're running
1202 setuid or setgid. */
1209 if (current_user.uid != u)
1211 FREE (current_user.user_name);
1212 FREE (current_user.shell);
1213 FREE (current_user.home_dir);
1214 current_user.user_name = current_user.shell = current_user.home_dir = (char *)NULL;
1216 current_user.uid = u;
1217 current_user.gid = getgid ();
1218 current_user.euid = geteuid ();
1219 current_user.egid = getegid ();
1221 /* See whether or not we are running setuid or setgid. */
1222 return (current_user.uid != current_user.euid) ||
1223 (current_user.gid != current_user.egid);
1227 disable_priv_mode ()
1229 setuid (current_user.uid);
1230 setgid (current_user.gid);
1231 current_user.euid = current_user.uid;
1232 current_user.egid = current_user.gid;
1235 #if defined (WORDEXP_OPTION)
1241 WORD_LIST *wl, *tl, *result;
1243 code = setjmp_nosigs (top_level);
1245 if (code != NOT_JUMPED)
1249 /* Some kind of throw to top_level has occurred. */
1251 return last_command_exit_value = 127;
1254 return last_command_exit_value;
1256 return last_command_exit_value = 1;
1258 command_error ("run_wordexp", CMDERR_BADJUMP, code, 0);
1262 /* Run it through the parser to get a list of words and expand them */
1263 if (words && *words)
1265 with_input_from_string (words, "--wordexp");
1266 if (parse_command () != 0)
1268 if (global_command == 0)
1273 if (global_command->type != cm_simple)
1275 wl = global_command->value.Simple->words;
1277 for (tl = wl; tl; tl = tl->next)
1278 tl->word->flags |= W_NOCOMSUB|W_NOPROCSUB;
1279 result = wl ? expand_words_no_vars (wl) : (WORD_LIST *)0;
1282 result = (WORD_LIST *)0;
1284 last_command_exit_value = 0;
1292 /* Count up the number of words and bytes, and print them. Don't count
1293 the trailing NUL byte. */
1294 for (nw = nb = 0, wl = result; wl; wl = wl->next)
1297 nb += strlen (wl->word->word);
1299 printf ("%u\n%u\n", nw, nb);
1300 /* Print each word on a separate line. This will have to be changed when
1301 the interface to glibc is completed. */
1302 for (wl = result; wl; wl = wl->next)
1303 printf ("%s\n", wl->word->word);
1309 #if defined (ONESHOT)
1310 /* Run one command, given as the argument to the -c option. Tell
1311 parse_and_execute not to fork for a simple command. */
1313 run_one_command (command)
1318 code = setjmp_nosigs (top_level);
1320 if (code != NOT_JUMPED)
1322 #if defined (PROCESS_SUBSTITUTION)
1323 unlink_fifo_list ();
1324 #endif /* PROCESS_SUBSTITUTION */
1327 /* Some kind of throw to top_level has occurred. */
1329 return last_command_exit_value = 127;
1332 return last_command_exit_value;
1334 return last_command_exit_value = 1;
1336 command_error ("run_one_command", CMDERR_BADJUMP, code, 0);
1339 return (parse_and_execute (savestring (command), "-c", SEVAL_NOHIST));
1341 #endif /* ONESHOT */
1344 bind_args (argv, arg_start, arg_end, start_index)
1346 int arg_start, arg_end, start_index;
1351 for (i = arg_start, args = (WORD_LIST *)NULL; i < arg_end; i++)
1352 args = make_word_list (make_word (argv[i]), args);
1355 args = REVERSE_LIST (args, WORD_LIST *);
1356 if (start_index == 0) /* bind to $0...$n for sh -c command */
1358 /* Posix.2 4.56.3 says that the first argument after sh -c command
1359 becomes $0, and the rest of the arguments become $1...$n */
1360 shell_name = savestring (args->word->word);
1361 FREE (dollar_vars[0]);
1362 dollar_vars[0] = savestring (args->word->word);
1363 remember_args (args->next, 1);
1364 push_args (args->next); /* BASH_ARGV and BASH_ARGC */
1366 else /* bind to $1...$n for shell script */
1368 remember_args (args, 1);
1369 push_args (args); /* BASH_ARGV and BASH_ARGC */
1372 dispose_words (args);
1381 remember_args ((WORD_LIST *)NULL, 1);
1382 pop_args (); /* Reset BASH_ARGV and BASH_ARGC */
1388 #if defined (DEBUGGER) && defined (DEBUGGER_START_FILE)
1391 old_errexit = exit_immediately_on_error;
1392 exit_immediately_on_error = 0;
1394 maybe_execute_file (DEBUGGER_START_FILE, 1);
1395 function_trace_mode = 1;
1397 exit_immediately_on_error += old_errexit;
1402 open_shell_script (script_name)
1405 int fd, e, fd_is_tty;
1406 char *filename, *path_filename, *t;
1410 #if defined (ARRAY_VARS)
1411 SHELL_VAR *funcname_v, *bash_source_v, *bash_lineno_v;
1412 ARRAY *funcname_a, *bash_source_a, *bash_lineno_a;
1415 filename = savestring (script_name);
1417 fd = open (filename, O_RDONLY);
1418 if ((fd < 0) && (errno == ENOENT) && (absolute_program (filename) == 0))
1421 /* If it's not in the current directory, try looking through PATH
1423 path_filename = find_path_file (script_name);
1427 filename = path_filename;
1428 fd = open (filename, O_RDONLY);
1437 file_error (filename);
1438 exit ((e == ENOENT) ? EX_NOTFOUND : EX_NOINPUT);
1441 free (dollar_vars[0]);
1442 dollar_vars[0] = exec_argv0 ? savestring (exec_argv0) : savestring (script_name);
1446 exec_argv0 = (char *)NULL;
1449 #if defined (ARRAY_VARS)
1450 GET_ARRAY_FROM_VAR ("FUNCNAME", funcname_v, funcname_a);
1451 GET_ARRAY_FROM_VAR ("BASH_SOURCE", bash_source_v, bash_source_a);
1452 GET_ARRAY_FROM_VAR ("BASH_LINENO", bash_lineno_v, bash_lineno_a);
1454 array_push (bash_source_a, filename);
1457 t = itos (executing_line_number ());
1458 array_push (bash_lineno_a, t);
1461 array_push (funcname_a, "main");
1465 fd_is_tty = isatty (fd);
1470 /* Only do this with non-tty file descriptors we can seek on. */
1471 if (fd_is_tty == 0 && (lseek (fd, 0L, 1) != -1))
1473 /* Check to see if the `file' in `bash file' is a binary file
1474 according to the same tests done by execute_simple_command (),
1475 and report an error and exit if it is. */
1476 sample_len = read (fd, sample, sizeof (sample));
1480 if ((fstat (fd, &sb) == 0) && S_ISDIR (sb.st_mode))
1481 internal_error (_("%s: is a directory"), filename);
1485 file_error (filename);
1489 else if (sample_len > 0 && (check_binary_file (sample, sample_len)))
1491 internal_error (_("%s: cannot execute binary file"), filename);
1492 exit (EX_BINARY_FILE);
1494 /* Now rewind the file back to the beginning. */
1498 /* Open the script. But try to move the file descriptor to a randomly
1499 large one, in the hopes that any descriptors used by the script will
1500 not match with ours. */
1501 fd = move_to_high_fd (fd, 1, -1);
1503 #if defined (BUFFERED_INPUT)
1504 default_buffered_input = fd;
1505 SET_CLOSE_ON_EXEC (default_buffered_input);
1506 #else /* !BUFFERED_INPUT */
1507 default_input = fdopen (fd, "r");
1509 if (default_input == 0)
1511 file_error (filename);
1515 SET_CLOSE_ON_EXEC (fd);
1516 if (fileno (default_input) != fd)
1517 SET_CLOSE_ON_EXEC (fileno (default_input));
1518 #endif /* !BUFFERED_INPUT */
1520 /* Just about the only way for this code to be executed is if something
1521 like `bash -i /dev/stdin' is executed. */
1522 if (interactive_shell && fd_is_tty)
1527 #if defined (BUFFERED_INPUT)
1528 default_buffered_input = 0;
1530 fclose (default_input);
1531 default_input = stdin;
1534 else if (forced_interactive && fd_is_tty == 0)
1535 /* But if a script is called with something like `bash -i scriptname',
1536 we need to do a non-interactive setup here, since we didn't do it
1538 init_interactive_script ();
1544 /* Initialize the input routines for the parser. */
1548 /* Make sure the fd from which we are reading input is not in
1550 #if defined (BUFFERED_INPUT)
1551 if (interactive == 0)
1552 sh_unset_nodelay_mode (default_buffered_input);
1554 #endif /* !BUFFERED_INPUT */
1555 sh_unset_nodelay_mode (fileno (stdin));
1557 /* with_input_from_stdin really means `with_input_from_readline' */
1558 if (interactive && no_line_editing == 0)
1559 with_input_from_stdin ();
1560 #if defined (BUFFERED_INPUT)
1561 else if (interactive == 0)
1562 with_input_from_buffered_stream (default_buffered_input, dollar_vars[0]);
1563 #endif /* BUFFERED_INPUT */
1565 with_input_from_stream (default_input, dollar_vars[0]);
1568 /* Close the current shell script input source and forget about it. This is
1569 extern so execute_cmd.c:initialize_subshell() can call it. If CHECK_ZERO
1570 is non-zero, we close default_buffered_input even if it's the standard
1573 unset_bash_input (check_zero)
1576 #if defined (BUFFERED_INPUT)
1577 if ((check_zero && default_buffered_input >= 0) ||
1578 (check_zero == 0 && default_buffered_input > 0))
1580 close_buffered_fd (default_buffered_input);
1581 default_buffered_input = bash_input.location.buffered_fd = -1;
1582 bash_input.type = st_none; /* XXX */
1584 #else /* !BUFFERED_INPUT */
1587 fclose (default_input);
1588 default_input = (FILE *)NULL;
1590 #endif /* !BUFFERED_INPUT */
1594 #if !defined (PROGRAM)
1595 # define PROGRAM "bash"
1599 set_shell_name (argv0)
1602 /* Here's a hack. If the name of this shell is "sh", then don't do
1603 any startup files; just try to be more like /bin/sh. */
1604 shell_name = argv0 ? base_pathname (argv0) : PROGRAM;
1606 if (argv0 && *argv0 == '-')
1608 if (*shell_name == '-')
1613 if (shell_name[0] == 's' && shell_name[1] == 'h' && shell_name[2] == '\0')
1615 if (shell_name[0] == 's' && shell_name[1] == 'u' && shell_name[2] == '\0')
1618 shell_name = argv0 ? argv0 : PROGRAM;
1619 FREE (dollar_vars[0]);
1620 dollar_vars[0] = savestring (shell_name);
1622 /* A program may start an interactive shell with
1623 "execl ("/bin/bash", "-", NULL)".
1624 If so, default the name of this shell to our name. */
1625 if (!shell_name || !*shell_name || (shell_name[0] == '-' && !shell_name[1]))
1626 shell_name = PROGRAM;
1632 expand_aliases = interactive_shell = startup_state = 1;
1637 init_noninteractive ()
1639 #if defined (HISTORY)
1640 bash_history_reinit (0);
1641 #endif /* HISTORY */
1642 interactive_shell = startup_state = interactive = 0;
1643 expand_aliases = posixly_correct; /* XXX - was 0 not posixly_correct */
1644 no_line_editing = 1;
1645 #if defined (JOB_CONTROL)
1646 /* Even if the shell is not interactive, enable job control if the -i or
1647 -m option is supplied at startup. */
1648 set_job_control (forced_interactive||jobs_m_flag);
1649 #endif /* JOB_CONTROL */
1653 init_interactive_script ()
1655 init_noninteractive ();
1656 expand_aliases = interactive_shell = startup_state = 1;
1660 get_current_user_info ()
1662 struct passwd *entry;
1664 /* Don't fetch this more than once. */
1665 if (current_user.user_name == 0)
1667 #if defined (__TANDEM)
1668 entry = getpwnam (getlogin ());
1670 entry = getpwuid (current_user.uid);
1674 current_user.user_name = savestring (entry->pw_name);
1675 current_user.shell = (entry->pw_shell && entry->pw_shell[0])
1676 ? savestring (entry->pw_shell)
1677 : savestring ("/bin/sh");
1678 current_user.home_dir = savestring (entry->pw_dir);
1682 current_user.user_name = _("I have no name!");
1683 current_user.user_name = savestring (current_user.user_name);
1684 current_user.shell = savestring ("/bin/sh");
1685 current_user.home_dir = savestring ("/");
1691 /* Do whatever is necessary to initialize the shell.
1692 Put new initializations in here. */
1698 /* Line buffer output for stderr and stdout. */
1699 if (shell_initialized == 0)
1701 sh_setlinebuf (stderr);
1702 sh_setlinebuf (stdout);
1705 /* Sort the array of shell builtins so that the binary search in
1706 find_shell_builtin () works correctly. */
1707 initialize_shell_builtins ();
1709 /* Initialize the trap signal handlers before installing our own
1710 signal handlers. traps.c:restore_original_signals () is responsible
1711 for restoring the original default signal handlers. That function
1712 is called when we make a new child. */
1713 initialize_traps ();
1714 initialize_signals (0);
1716 /* It's highly unlikely that this will change. */
1717 if (current_host_name == 0)
1719 /* Initialize current_host_name. */
1720 if (gethostname (hostname, 255) < 0)
1721 current_host_name = "??host??";
1723 current_host_name = savestring (hostname);
1726 /* Initialize the stuff in current_user that comes from the password
1727 file. We don't need to do this right away if the shell is not
1729 if (interactive_shell)
1730 get_current_user_info ();
1732 /* Initialize our interface to the tilde expander. */
1733 tilde_initialize ();
1735 /* Initialize internal and environment variables. Don't import shell
1736 functions from the environment if we are running in privileged or
1737 restricted mode or if the shell is running setuid. */
1738 #if defined (RESTRICTED_SHELL)
1739 initialize_shell_variables (shell_environment, privileged_mode||restricted||running_setuid);
1741 initialize_shell_variables (shell_environment, privileged_mode||running_setuid);
1744 /* Initialize the data structures for storing and running jobs. */
1745 initialize_job_control (jobs_m_flag);
1747 /* Initialize input streams to null. */
1748 initialize_bash_input ();
1750 initialize_flags ();
1752 /* Initialize the shell options. Don't import the shell options
1753 from the environment variables $SHELLOPTS or $BASHOPTS if we are
1754 running in privileged or restricted mode or if the shell is running
1756 #if defined (RESTRICTED_SHELL)
1757 initialize_shell_options (privileged_mode||restricted||running_setuid);
1758 initialize_bashopts (privileged_mode||restricted||running_setuid);
1760 initialize_shell_options (privileged_mode||running_setuid);
1761 initialize_bashopts (privileged_mode||running_setuid);
1765 /* Function called by main () when it appears that the shell has already
1766 had some initialization performed. This is supposed to reset the world
1767 back to a pristine state, as if we had been exec'ed. */
1769 shell_reinitialize ()
1771 /* The default shell prompts. */
1772 primary_prompt = PPROMPT;
1773 secondary_prompt = SPROMPT;
1775 /* Things that get 1. */
1776 current_command_number = 1;
1778 /* We have decided that the ~/.bashrc file should not be executed
1779 for the invocation of each shell script. If the variable $ENV
1780 (or $BASH_ENV) is set, its value is used as the name of a file
1782 no_rc = no_profile = 1;
1784 /* Things that get 0. */
1785 login_shell = make_login_shell = interactive = executing = 0;
1786 debugging = do_version = line_number = last_command_exit_value = 0;
1787 forced_interactive = interactive_shell = subshell_environment = 0;
1790 /* XXX - should we set jobs_m_flag to 0 here? */
1792 #if defined (HISTORY)
1793 bash_history_reinit (0);
1794 #endif /* HISTORY */
1796 #if defined (RESTRICTED_SHELL)
1798 #endif /* RESTRICTED_SHELL */
1800 /* Ensure that the default startup file is used. (Except that we don't
1801 execute this file for reinitialized shells). */
1802 bashrc_file = "~/.bashrc";
1804 /* Delete all variables and functions. They will be reinitialized when
1805 the environment is parsed. */
1806 delete_all_contexts (shell_variables);
1807 delete_all_variables (shell_functions);
1809 reinit_special_variables ();
1811 #if defined (READLINE)
1812 bashline_reinitialize ();
1815 shell_reinitialized = 1;
1819 show_shell_usage (fp, extra)
1824 char *set_opts, *s, *t;
1827 fprintf (fp, _("GNU bash, version %s-(%s)\n"), shell_version_string (), MACHTYPE);
1828 fprintf (fp, _("Usage:\t%s [GNU long option] [option] ...\n\t%s [GNU long option] [option] script-file ...\n"),
1829 shell_name, shell_name);
1830 fputs (_("GNU long options:\n"), fp);
1831 for (i = 0; long_args[i].name; i++)
1832 fprintf (fp, "\t--%s\n", long_args[i].name);
1834 fputs (_("Shell options:\n"), fp);
1835 fputs (_("\t-ilrsD or -c command or -O shopt_option\t\t(invocation only)\n"), fp);
1837 for (i = 0, set_opts = 0; shell_builtins[i].name; i++)
1838 if (STREQ (shell_builtins[i].name, "set"))
1839 set_opts = savestring (shell_builtins[i].short_doc);
1842 s = strchr (set_opts, '[');
1847 t = strchr (s, ']');
1850 fprintf (fp, _("\t-%s or -o option\n"), s);
1856 fprintf (fp, _("Type `%s -c \"help set\"' for more information about shell options.\n"), shell_name);
1857 fprintf (fp, _("Type `%s -c help' for more information about shell builtin commands.\n"), shell_name);
1858 fprintf (fp, _("Use the `bashbug' command to report bugs.\n"));
1863 add_shopt_to_alist (opt, on_or_off)
1867 if (shopt_ind >= shopt_len)
1870 shopt_alist = (STRING_INT_ALIST *)xrealloc (shopt_alist, shopt_len * sizeof (shopt_alist[0]));
1872 shopt_alist[shopt_ind].word = opt;
1873 shopt_alist[shopt_ind].token = on_or_off;
1882 for (i = 0; i < shopt_ind; i++)
1883 if (shopt_setopt (shopt_alist[i].word, (shopt_alist[i].token == '-')) != EXECUTION_SUCCESS)
1887 shopt_ind = shopt_len = 0;