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, 1989, 1991 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 it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License along
  19 with Bash; see the file COPYING.  If not, write to the Free Software
  20 Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA.
  21
  22 $PRODUCES source.c
  23
  24 $BUILTIN source
  25 $FUNCTION source_builtin
  26 $SHORT_DOC source filename
  27 Read and execute commands from FILENAME and return.  The pathnames
  28 in $PATH are used to find the directory containing FILENAME.
  29 $END
  30 $BUILTIN .
  31 $DOCNAME dot
  32 $FUNCTION source_builtin
  33 $SHORT_DOC . filename
  34 Read and execute commands from FILENAME and return.  The pathnames
  35 in $PATH are used to find the directory containing FILENAME.
  36 $END
  37 /* source.c - Implements the `.' and `source' builtins. */
  38
  39 #include <config.h>
  40
  41 #include "../bashtypes.h"
  42 #include "posixstat.h"
  43 #include "filecntl.h"
  44 #ifndef _MINIX
  45 #  include <sys/file.h>
  46 #endif
  47 #include <errno.h>
  48
  49 #if defined (HAVE_UNISTD_H)
  50 #  include <unistd.h>
  51 #endif
  52
  53 #include "../bashansi.h"
  54
  55 #include "../shell.h"
  56 #include "../findcmd.h"
  57 #include "common.h"
  58
  59 #if !defined (errno)
  60 extern int errno;
  61 #endif /* !errno */
  62
  63 #if defined (RESTRICTED_SHELL)
  64 extern int restricted;
  65 #endif
  66
  67 /* If non-zero, `.' uses $PATH to look up the script to be sourced. */
  68 int source_uses_path = 1;
  69
  70 /* If non-zero, `.' looks in the current directory if the filename argument
  71    is not found in the $PATH. */
  72 int source_searches_cwd = 1;
  73
  74 /* If this . script is supplied arguments, we save the dollar vars and
  75    replace them with the script arguments for the duration of the script's
  76    execution.  If the script does not change the dollar vars, we restore
  77    what we saved.  If the dollar vars are changed in the script, and we are
  78    not executing a shell function, we leave the new values alone and free
  79    the saved values. */
  80 static void
  81 maybe_pop_dollar_vars ()
  82 {
  83   if (variable_context == 0 && dollar_vars_changed ())
  84     {
  85       dispose_saved_dollar_vars ();
  86       set_dollar_vars_unchanged ();
  87     }
  88   else
  89     pop_dollar_vars ();
  90 }
  91
  92 /* Read and execute commands from the file passed as argument.  Guess what.
  93    This cannot be done in a subshell, since things like variable assignments
  94    take place in there.  So, I open the file, place it into a large string,
  95    close the file, and then execute the string. */
  96 int
  97 source_builtin (list)
  98      WORD_LIST *list;
  99 {
 100   int result;
 101   char *filename;
 102
 103   if (list == 0)
 104     {
 105       builtin_error ("filename argument required");
 106       builtin_usage ();
 107       return (EX_USAGE);
 108     }
 109
 110   if (no_options (list))
 111     return (EX_USAGE);
 112
 113 #if defined (RESTRICTED_SHELL)
 114   if (restricted && strchr (list->word->word, '/'))
 115     {
 116       builtin_error ("%s: restricted", list->word->word);
 117       return (EXECUTION_FAILURE);
 118     }
 119 #endif
 120
 121   filename = (char *)NULL;
 122   if (source_uses_path)
 123     filename = find_path_file (list->word->word);
 124   if (filename == 0)
 125     {
 126       if (source_searches_cwd == 0)
 127         {
 128           builtin_error ("%s: file not found", list->word->word);
 129           return (EXECUTION_FAILURE);
 130         }
 131       else
 132         filename = savestring (list->word->word);
 133     }
 134
 135   begin_unwind_frame ("source");
 136   add_unwind_protect ((Function *)xfree, filename);
 137
 138   if (list->next)
 139     {
 140       push_dollar_vars ();
 141       add_unwind_protect ((Function *)maybe_pop_dollar_vars, (char *)NULL);
 142       remember_args (list->next, 1);
 143     }
 144   set_dollar_vars_unchanged ();
 145
 146   result = source_file (filename);
 147
 148   run_unwind_frame ("source");
 149
 150   return (result);
 151 }