builtins/evalfile.c

   1 /* evalfile.c - read and evaluate commands from a file or file descriptor */
   2
   3 /* Copyright (C) 1996-2009 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   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.
  11
  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.
  16
  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/>.
  19 */
  20
  21 #include <config.h>
  22
  23 #if defined (HAVE_UNISTD_H)
  24 #  include <unistd.h>
  25 #endif
  26
  27 #include "../bashtypes.h"
  28 #include "posixstat.h"
  29 #include "filecntl.h"
  30
  31 #include <stdio.h>
  32 #include <signal.h>
  33 #include <errno.h>
  34
  35 #include "../bashansi.h"
  36 #include "../bashintl.h"
  37
  38 #include "../shell.h"
  39 #include "../jobs.h"
  40 #include "../builtins.h"
  41 #include "../flags.h"
  42 #include "../input.h"
  43 #include "../execute_cmd.h"
  44 #include "../trap.h"
  45
  46 #if defined (HISTORY)
  47 #  include "../bashhist.h"
  48 #endif
  49
  50 #include <typemax.h>
  51
  52 #include "common.h"
  53
  54 #if !defined (errno)
  55 extern int errno;
  56 #endif
  57
  58 /* Flags for _evalfile() */
  59 #define FEVAL_ENOENTOK          0x001
  60 #define FEVAL_BUILTIN           0x002
  61 #define FEVAL_UNWINDPROT        0x004
  62 #define FEVAL_NONINT            0x008
  63 #define FEVAL_LONGJMP           0x010
  64 #define FEVAL_HISTORY           0x020
  65 #define FEVAL_CHECKBINARY       0x040
  66 #define FEVAL_REGFILE           0x080
  67 #define FEVAL_NOPUSHARGS        0x100
  68
  69 extern int posixly_correct;
  70 extern int indirection_level, subshell_environment;
  71 extern int return_catch_flag, return_catch_value;
  72 extern int last_command_exit_value;
  73 extern int executing_command_builtin;
  74
  75 /* How many `levels' of sourced files we have. */
  76 int sourcelevel = 0;
  77
  78 static int
  79 _evalfile (filename, flags)
  80      const char *filename;
  81      int flags;
  82 {
  83   volatile int old_interactive;
  84   procenv_t old_return_catch;
  85   int return_val, fd, result, pflags, i, nnull;
  86   ssize_t nr;                   /* return value from read(2) */
  87   char *string;
  88   struct stat finfo;
  89   size_t file_size;
  90   sh_vmsg_func_t *errfunc;
  91 #if defined (ARRAY_VARS)
  92   SHELL_VAR *funcname_v, *nfv, *bash_source_v, *bash_lineno_v;
  93   ARRAY *funcname_a, *bash_source_a, *bash_lineno_a;
  94 #  if defined (DEBUGGER)
  95   SHELL_VAR *bash_argv_v, *bash_argc_v;
  96   ARRAY *bash_argv_a, *bash_argc_a;
  97 #  endif
  98   char *t, tt[2];
  99 #endif
 100
 101   USE_VAR(pflags);
 102
 103 #if defined (ARRAY_VARS)
 104   GET_ARRAY_FROM_VAR ("FUNCNAME", funcname_v, funcname_a);
 105   GET_ARRAY_FROM_VAR ("BASH_SOURCE", bash_source_v, bash_source_a);
 106   GET_ARRAY_FROM_VAR ("BASH_LINENO", bash_lineno_v, bash_lineno_a);
 107 #  if defined (DEBUGGER)
 108   GET_ARRAY_FROM_VAR ("BASH_ARGV", bash_argv_v, bash_argv_a);
 109   GET_ARRAY_FROM_VAR ("BASH_ARGC", bash_argc_v, bash_argc_a);
 110 #  endif
 111 #endif
 112
 113   fd = open (filename, O_RDONLY);
 114
 115   if (fd < 0 || (fstat (fd, &finfo) == -1))
 116     {
 117 file_error_and_exit:
 118       if (((flags & FEVAL_ENOENTOK) == 0) || errno != ENOENT)
 119         file_error (filename);
 120
 121       if (flags & FEVAL_LONGJMP)
 122         {
 123           last_command_exit_value = 1;
 124           jump_to_top_level (EXITPROG);
 125         }
 126
 127       return ((flags & FEVAL_BUILTIN) ? EXECUTION_FAILURE
 128                                       : ((errno == ENOENT) ? 0 : -1));
 129     }
 130
 131   errfunc = ((flags & FEVAL_BUILTIN) ? builtin_error : internal_error);
 132
 133   if (S_ISDIR (finfo.st_mode))
 134     {
 135       (*errfunc) (_("%s: is a directory"), filename);
 136       return ((flags & FEVAL_BUILTIN) ? EXECUTION_FAILURE : -1);
 137     }
 138   else if ((flags & FEVAL_REGFILE) && S_ISREG (finfo.st_mode) == 0)
 139     {
 140       (*errfunc) (_("%s: not a regular file"), filename);
 141       return ((flags & FEVAL_BUILTIN) ? EXECUTION_FAILURE : -1);
 142     }
 143
 144   file_size = (size_t)finfo.st_size;
 145   /* Check for overflow with large files. */
 146   if (file_size != finfo.st_size || file_size + 1 < file_size)
 147     {
 148       (*errfunc) (_("%s: file is too large"), filename);
 149       return ((flags & FEVAL_BUILTIN) ? EXECUTION_FAILURE : -1);
 150     }
 151
 152   if (S_ISREG (finfo.st_mode) && file_size <= SSIZE_MAX)
 153     {
 154       string = (char *)xmalloc (1 + file_size);
 155       nr = read (fd, string, file_size);
 156       if (nr >= 0)
 157         string[nr] = '\0';
 158     }
 159   else
 160     nr = zmapfd (fd, &string, 0);
 161
 162   return_val = errno;
 163   close (fd);
 164   errno = return_val;
 165
 166   if (nr < 0)           /* XXX was != file_size, not < 0 */
 167     {
 168       free (string);
 169       goto file_error_and_exit;
 170     }
 171
 172   if (nr == 0)
 173     {
 174       free (string);
 175       return ((flags & FEVAL_BUILTIN) ? EXECUTION_SUCCESS : 1);
 176     }
 177
 178   if ((flags & FEVAL_CHECKBINARY) &&
 179       check_binary_file (string, (nr > 80) ? 80 : nr))
 180     {
 181       free (string);
 182       (*errfunc) (_("%s: cannot execute binary file"), filename);
 183       return ((flags & FEVAL_BUILTIN) ? EX_BINARY_FILE : -1);
 184     }
 185
 186   i = strlen (string);
 187   if (i < nr)
 188     {
 189       for (nnull = i = 0; i < nr; i++)
 190         if (string[i] == '\0')
 191           {
 192             memmove (string+i, string+i+1, nr - i);
 193             nr--;
 194             /* Even if the `check binary' flag is not set, we want to avoid
 195                sourcing files with more than 256 null characters -- that
 196                probably indicates a binary file. */
 197             if ((flags & FEVAL_BUILTIN) && ++nnull > 256)
 198               {
 199                 free (string);
 200                 (*errfunc) (_("%s: cannot execute binary file"), filename);
 201                 return ((flags & FEVAL_BUILTIN) ? EX_BINARY_FILE : -1);
 202               }
 203           }
 204     }
 205
 206   if (flags & FEVAL_UNWINDPROT)
 207     {
 208       begin_unwind_frame ("_evalfile");
 209
 210       unwind_protect_int (return_catch_flag);
 211       unwind_protect_jmp_buf (return_catch);
 212       if (flags & FEVAL_NONINT)
 213         unwind_protect_int (interactive);
 214       unwind_protect_int (sourcelevel);
 215     }
 216   else
 217     {
 218       COPY_PROCENV (return_catch, old_return_catch);
 219       if (flags & FEVAL_NONINT)
 220         old_interactive = interactive;
 221     }
 222
 223   if (flags & FEVAL_NONINT)
 224     interactive = 0;
 225
 226   return_catch_flag++;
 227   sourcelevel++;
 228
 229 #if defined (ARRAY_VARS)
 230   array_push (bash_source_a, (char *)filename);
 231   t = itos (executing_line_number ());
 232   array_push (bash_lineno_a, t);
 233   free (t);
 234   array_push (funcname_a, "source");    /* not exactly right */
 235 #  if defined (DEBUGGER)
 236   /* Have to figure out a better way to do this when `source' is supplied
 237      arguments */
 238   if ((flags & FEVAL_NOPUSHARGS) == 0)
 239     {
 240       array_push (bash_argv_a, (char *)filename);
 241       tt[0] = '1'; tt[1] = '\0';
 242       array_push (bash_argc_a, tt);
 243     }
 244 #  endif
 245 #endif
 246
 247   /* set the flags to be passed to parse_and_execute */
 248   pflags = SEVAL_RESETLINE;
 249   pflags |= (flags & FEVAL_HISTORY) ? 0 : SEVAL_NOHIST;
 250
 251   if (flags & FEVAL_BUILTIN)
 252     result = EXECUTION_SUCCESS;
 253
 254   return_val = setjmp (return_catch);
 255
 256   /* If `return' was seen outside of a function, but in the script, then
 257      force parse_and_execute () to clean up. */
 258   if (return_val)
 259     {
 260       parse_and_execute_cleanup ();
 261       result = return_catch_value;
 262     }
 263   else
 264     result = parse_and_execute (string, filename, pflags);
 265
 266   if (flags & FEVAL_UNWINDPROT)
 267     run_unwind_frame ("_evalfile");
 268   else
 269     {
 270       if (flags & FEVAL_NONINT)
 271         interactive = old_interactive;
 272       return_catch_flag--;
 273       sourcelevel--;
 274       COPY_PROCENV (old_return_catch, return_catch);
 275     }
 276
 277 #if defined (ARRAY_VARS)
 278   /* These two variables cannot be unset, and cannot be affected by the
 279      sourced file. */
 280   array_pop (bash_source_a);
 281   array_pop (bash_lineno_a);
 282
 283   /* FUNCNAME can be unset, and so can potentially be changed by the
 284      sourced file. */
 285   GET_ARRAY_FROM_VAR ("FUNCNAME", nfv, funcname_a);
 286   if (nfv == funcname_v)
 287     array_pop (funcname_a);
 288 #  if defined (DEBUGGER)
 289   if ((flags & FEVAL_NOPUSHARGS) == 0)
 290     {
 291       array_pop (bash_argc_a);
 292       array_pop (bash_argv_a);
 293     }
 294 #  endif
 295 #endif
 296
 297   return ((flags & FEVAL_BUILTIN) ? result : 1);
 298 }
 299
 300 int
 301 maybe_execute_file (fname, force_noninteractive)
 302      const char *fname;
 303      int force_noninteractive;
 304 {
 305   char *filename;
 306   int result, flags;
 307
 308   filename = bash_tilde_expand (fname, 0);
 309   flags = FEVAL_ENOENTOK;
 310   if (force_noninteractive)
 311     flags |= FEVAL_NONINT;
 312   result = _evalfile (filename, flags);
 313   free (filename);
 314   return result;
 315 }
 316
 317 #if defined (HISTORY)
 318 int
 319 fc_execute_file (filename)
 320      const char *filename;
 321 {
 322   int flags;
 323
 324   /* We want these commands to show up in the history list if
 325      remember_on_history is set. */
 326   flags = FEVAL_ENOENTOK|FEVAL_HISTORY|FEVAL_REGFILE;
 327   return (_evalfile (filename, flags));
 328 }
 329 #endif /* HISTORY */
 330
 331 int
 332 source_file (filename, sflags)
 333      const char *filename;
 334      int sflags;
 335 {
 336   int flags, rval;
 337
 338   flags = FEVAL_BUILTIN|FEVAL_UNWINDPROT|FEVAL_NONINT;
 339   if (sflags)
 340     flags |= FEVAL_NOPUSHARGS;
 341   /* POSIX shells exit if non-interactive and file error. */
 342   if (posixly_correct && interactive_shell == 0 && executing_command_builtin == 0)
 343     flags |= FEVAL_LONGJMP;
 344   rval = _evalfile (filename, flags);
 345
 346   run_return_trap ();
 347   return rval;
 348 }