builtins/source.def

   1 This file is source.def, from which is created source.c.
   2 It implements the builtins "." and  "source" in Bash.
   3
   4 Copyright (C) 1987-2009 Free Software Foundation, Inc.
   5
   6 This file is part of GNU Bash, the Bourne Again SHell.
   7
   8 Bash is free software: you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation, either version 3 of the License, or
  11 (at your option) any later version.
  12
  13 Bash is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  20
  21 $PRODUCES source.c
  22
  23 $BUILTIN source
  24 $FUNCTION source_builtin
  25 $SHORT_DOC source filename [arguments]
  26 Execute commands from a file in the current shell.
  27
  28 Read and execute commands from FILENAME in the current shell.  The
  29 entries in $PATH are used to find the directory containing FILENAME.
  30 If any ARGUMENTS are supplied, they become the positional parameters
  31 when FILENAME is executed.
  32
  33 Exit Status:
  34 Returns the status of the last command executed in FILENAME; fails if
  35 FILENAME cannot be read.
  36 $END
  37
  38 $BUILTIN .
  39 $DOCNAME dot
  40 $FUNCTION source_builtin
  41 $SHORT_DOC . filename [arguments]
  42 Execute commands from a file in the current shell.
  43
  44 Read and execute commands from FILENAME in the current shell.  The
  45 entries in $PATH are used to find the directory containing FILENAME.
  46 If any ARGUMENTS are supplied, they become the positional parameters
  47 when FILENAME is executed.
  48
  49 Exit Status:
  50 Returns the status of the last command executed in FILENAME; fails if
  51 FILENAME cannot be read.
  52 $END
  53
  54 #include <config.h>
  55
  56 #include "../bashtypes.h"
  57 #include "posixstat.h"
  58 #include "filecntl.h"
  59 #if ! defined(_MINIX) && defined (HAVE_SYS_FILE_H)
  60 #  include <sys/file.h>
  61 #endif
  62 #include <errno.h>
  63
  64 #if defined (HAVE_UNISTD_H)
  65 #  include <unistd.h>
  66 #endif
  67
  68 #include "../bashansi.h"
  69 #include "../bashintl.h"
  70
  71 #include "../shell.h"
  72 #include "../flags.h"
  73 #include "../findcmd.h"
  74 #include "common.h"
  75 #include "bashgetopt.h"
  76 #include "../trap.h"
  77
  78 #if !defined (errno)
  79 extern int errno;
  80 #endif /* !errno */
  81
  82 extern int posixly_correct;
  83 extern int last_command_exit_value;
  84 extern int executing_command_builtin;
  85
  86 static void maybe_pop_dollar_vars __P((void));
  87
  88 /* If non-zero, `.' uses $PATH to look up the script to be sourced. */
  89 int source_uses_path = 1;
  90
  91 /* If non-zero, `.' looks in the current directory if the filename argument
  92    is not found in the $PATH. */
  93 int source_searches_cwd = 1;
  94
  95 /* If this . script is supplied arguments, we save the dollar vars and
  96    replace them with the script arguments for the duration of the script's
  97    execution.  If the script does not change the dollar vars, we restore
  98    what we saved.  If the dollar vars are changed in the script, and we are
  99    not executing a shell function, we leave the new values alone and free
 100    the saved values. */
 101 static void
 102 maybe_pop_dollar_vars ()
 103 {
 104   if (variable_context == 0 && (dollar_vars_changed () & ARGS_SETBLTIN))
 105     dispose_saved_dollar_vars ();
 106   else
 107     pop_dollar_vars ();
 108   if (debugging_mode)
 109     pop_args ();        /* restore BASH_ARGC and BASH_ARGV */
 110   set_dollar_vars_unchanged ();
 111 }
 112
 113 /* Read and execute commands from the file passed as argument.  Guess what.
 114    This cannot be done in a subshell, since things like variable assignments
 115    take place in there.  So, I open the file, place it into a large string,
 116    close the file, and then execute the string. */
 117 int
 118 source_builtin (list)
 119      WORD_LIST *list;
 120 {
 121   int result;
 122   char *filename, *debug_trap;
 123
 124   if (no_options (list))
 125     return (EX_USAGE);
 126   list = loptend;
 127
 128   if (list == 0)
 129     {
 130       builtin_error (_("filename argument required"));
 131       builtin_usage ();
 132       return (EX_USAGE);
 133     }
 134
 135 #if defined (RESTRICTED_SHELL)
 136   if (restricted && strchr (list->word->word, '/'))
 137     {
 138       sh_restricted (list->word->word);
 139       return (EXECUTION_FAILURE);
 140     }
 141 #endif
 142
 143   filename = (char *)NULL;
 144   /* XXX -- should this be absolute_pathname? */
 145   if (posixly_correct && strchr (list->word->word, '/'))
 146     filename = savestring (list->word->word);
 147   else if (absolute_pathname (list->word->word))
 148     filename = savestring (list->word->word);
 149   else if (source_uses_path)
 150     filename = find_path_file (list->word->word);
 151   if (filename == 0)
 152     {
 153       if (source_searches_cwd == 0)
 154         {
 155           builtin_error (_("%s: file not found"), list->word->word);
 156           if (posixly_correct && interactive_shell == 0 && executing_command_builtin == 0)
 157             {
 158               last_command_exit_value = 1;
 159               jump_to_top_level (EXITPROG);
 160             }
 161           return (EXECUTION_FAILURE);
 162         }
 163       else
 164         filename = savestring (list->word->word);
 165     }
 166
 167   begin_unwind_frame ("source");
 168   add_unwind_protect ((Function *)xfree, filename);
 169
 170   if (list->next)
 171     {
 172       push_dollar_vars ();
 173       add_unwind_protect ((Function *)maybe_pop_dollar_vars, (char *)NULL);
 174       remember_args (list->next, 1);
 175       if (debugging_mode)
 176         push_args (list->next); /* Update BASH_ARGV and BASH_ARGC */
 177     }
 178   set_dollar_vars_unchanged ();
 179
 180   /* Don't inherit the DEBUG trap unless function_trace_mode (overloaded)
 181      is set.  XXX - should sourced files inherit the RETURN trap?  Functions
 182      don't. */
 183   debug_trap = TRAP_STRING (DEBUG_TRAP);
 184   if (debug_trap && function_trace_mode == 0)
 185     {
 186       debug_trap = savestring (debug_trap);
 187       add_unwind_protect (xfree, debug_trap);
 188       add_unwind_protect (set_debug_trap, debug_trap);
 189       restore_default_signal (DEBUG_TRAP);
 190     }
 191
 192   result = source_file (filename, (list && list->next));
 193
 194   run_unwind_frame ("source");
 195
 196   return (result);
 197 }