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) 1987-2015 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   invalidate_cached_quoted_dollar_at ();        /* just invalidate to be safe */
 112 }
 113
 114 /* Read and execute commands from the file passed as argument.  Guess what.
 115    This cannot be done in a subshell, since things like variable assignments
 116    take place in there.  So, I open the file, place it into a large string,
 117    close the file, and then execute the string. */
 118 int
 119 source_builtin (list)
 120      WORD_LIST *list;
 121 {
 122   int result;
 123   char *filename, *debug_trap, *x;
 124
 125   if (no_options (list))
 126     return (EX_USAGE);
 127   list = loptend;
 128
 129   if (list == 0)
 130     {
 131       builtin_error (_("filename argument required"));
 132       builtin_usage ();
 133       return (EX_USAGE);
 134     }
 135
 136 #if defined (RESTRICTED_SHELL)
 137   if (restricted && strchr (list->word->word, '/'))
 138     {
 139       sh_restricted (list->word->word);
 140       return (EXECUTION_FAILURE);
 141     }
 142 #endif
 143
 144   filename = (char *)NULL;
 145   /* XXX -- should this be absolute_pathname? */
 146   if (posixly_correct && strchr (list->word->word, '/'))
 147     filename = savestring (list->word->word);
 148   else if (absolute_pathname (list->word->word))
 149     filename = savestring (list->word->word);
 150   else if (source_uses_path)
 151     filename = find_path_file (list->word->word);
 152   if (filename == 0)
 153     {
 154       if (source_searches_cwd == 0)
 155         {
 156           x = printable_filename (list->word->word, 0);
 157           builtin_error (_("%s: file not found"), x);
 158           if (x != list->word->word)
 159             free (x);
 160           if (posixly_correct && interactive_shell == 0 && executing_command_builtin == 0)
 161             {
 162               last_command_exit_value = 1;
 163               jump_to_top_level (EXITPROG);
 164             }
 165           return (EXECUTION_FAILURE);
 166         }
 167       else
 168         filename = savestring (list->word->word);
 169     }
 170
 171   begin_unwind_frame ("source");
 172   add_unwind_protect ((Function *)xfree, filename);
 173
 174   if (list->next)
 175     {
 176       push_dollar_vars ();
 177       add_unwind_protect ((Function *)maybe_pop_dollar_vars, (char *)NULL);
 178       remember_args (list->next, 1);
 179       if (debugging_mode)
 180         push_args (list->next); /* Update BASH_ARGV and BASH_ARGC */
 181     }
 182   set_dollar_vars_unchanged ();
 183
 184   /* Don't inherit the DEBUG trap unless function_trace_mode (overloaded)
 185      is set.  XXX - should sourced files inherit the RETURN trap?  Functions
 186      don't. */
 187   debug_trap = TRAP_STRING (DEBUG_TRAP);
 188   if (debug_trap && function_trace_mode == 0)
 189     {
 190       debug_trap = savestring (debug_trap);
 191       add_unwind_protect (xfree, debug_trap);
 192       add_unwind_protect (maybe_set_debug_trap, debug_trap);
 193       restore_default_signal (DEBUG_TRAP);
 194     }
 195
 196   result = source_file (filename, (list && list->next));
 197
 198   run_unwind_frame ("source");
 199
 200   return (result);
 201 }