Attachment 71266 Details for Bug 155246

posix/execvp.c from glibc-2.3.5-40.src.rpm

execvp.c (text/plain), 5.22 KB, created by Jeff Hollensen on 2006-03-05 00:49:07 UTC

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Creator: Jeff Hollensen

Created: 2006-03-05 00:49:07 UTC

Size: 5.22 KB

patch

obsolete

>/* Copyright (C) 1991,92,1995-99,2002,2004,2005 Free Software Foundation, Inc.
>   This file is part of the GNU C Library.
>
>   The GNU C Library is free software; you can redistribute it and/or
>   modify it under the terms of the GNU Lesser General Public
>   License as published by the Free Software Foundation; either
>   version 2.1 of the License, or (at your option) any later version.
>
>   The GNU C Library is distributed in the hope that it will be useful,
>   but WITHOUT ANY WARRANTY; without even the implied warranty of
>   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
>   Lesser General Public License for more details.
>
>   You should have received a copy of the GNU Lesser General Public
>   License along with the GNU C Library; if not, write to the Free
>   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
>   02111-1307 USA.  */
>
>#include <unistd.h>
>#include <stdarg.h>
>#include <stdbool.h>
>#include <stdlib.h>
>#include <string.h>
>#include <errno.h>
>#include <paths.h>
>
>
>/* The file is accessible but it is not an executable file.  Invoke
>   the shell to interpret it as a script.  */
>static char **
>internal_function
>allocate_scripts_argv (const char *file, char *const argv[])
>{
>  /* Count the arguments.  */
>  int argc = 0;
>  while (argv[argc++])
>    ;
>
>  /* Construct an argument list for the shell.  */
>  char **new_argv = (char **) malloc ((argc + 1) * sizeof (char *));
>  if (new_argv != NULL)
>    {
>      new_argv[0] = (char *) _PATH_BSHELL;
>      new_argv[1] = (char *) file;
>      while (argc > 1)
>	{
>	  new_argv[argc] = argv[argc - 1];
>	  --argc;
>	}
>    }
>
>  return new_argv;
>}
>
>
>/* Execute FILE, searching in the `PATH' environment variable if it contains
>   no slashes, with arguments ARGV and environment from `environ'.  */
>int
>execvp (file, argv)
>     const char *file;
>     char *const argv[];
>{
>  if (*file == '\0')
>    {
>      /* We check the simple case first. */
>      __set_errno (ENOENT);
>      return -1;
>    }
>
>  char **script_argv = NULL;
>
>  if (strchr (file, '/') != NULL)
>    {
>      /* Don't search when it contains a slash.  */
>      __execve (file, argv, __environ);
>
>      if (errno == ENOEXEC)
>	{
>	  script_argv = allocate_scripts_argv (file, argv);
>	  if (script_argv != NULL)
>	    {
>	      __execve (script_argv[0], script_argv, __environ);
>
>	      free (script_argv);
>	    }
>	}
>    }
>  else
>    {
>      char *path = getenv ("PATH");
>      bool path_malloc = false;
>      if (path == NULL)
>	{
>	  /* There is no `PATH' in the environment.
>	     The default search path is the current directory
>	     followed by the path `confstr' returns for `_CS_PATH'.  */
>	  size_t len = confstr (_CS_PATH, (char *) NULL, 0);
>	  path = (char *) malloc (1 + len);
>	  if (path == NULL)
>	    return -1;
>	  path[0] = ':';
>	  (void) confstr (_CS_PATH, path + 1, len);
>	  path_malloc = true;
>	}
>
>      size_t len = strlen (file) + 1;
>      size_t pathlen = strlen (path);
>      char *name = malloc (pathlen + len + 1);
>      if (name == NULL)
>	{
>	  if (path_malloc)
>	    free (path);
>	  return -1;
>	}
>      /* Copy the file name at the top.  */
>      name = (char *) memcpy (name + pathlen + 1, file, len);
>      /* And add the slash.  */
>      *--name = '/';
>
>      bool got_eacces = false;
>      char *p = path;
>      do
>	{
>	  char *startp;
>
>	  path = p;
>	  p = __strchrnul (path, ':');
>
>	  if (p == path)
>	    /* Two adjacent colons, or a colon at the beginning or the end
>	       of `PATH' means to search the current directory.  */
>	    startp = name + 1;
>	  else
>	    startp = (char *) memcpy (name - (p - path), path, p - path);
>
>	  /* Try to execute this name.  If it works, execve will not return. */
>	  __execve (startp, argv, __environ);
>
>	  if (errno == ENOEXEC)
>	    {
>	      if (script_argv == NULL)
>		{
>		  script_argv = allocate_scripts_argv (startp, argv);
>		  if (script_argv == NULL)
>		    {
>		      /* A possible EACCES error is not as important as
>			 the ENOMEM.  */
>		      got_eacces = false;
>		      break;
>		    }
>		}
>
>	      __execve (script_argv[0], script_argv, __environ);
>	    }
>
>	  switch (errno)
>	    {
>	    case EACCES:
>	      /* Record the we got a `Permission denied' error.  If we end
>		 up finding no executable we can use, we want to diagnose
>		 that we did find one but were denied access.  */
>	      got_eacces = true;
>	    case ENOENT:
>	    case ESTALE:
>	    case ENOTDIR:
>	      /* Those errors indicate the file is missing or not executable
>		 by us, in which case we want to just try the next path
>		 directory.  */
>	    case ENODEV:
>	    case ETIMEDOUT:
>	      /* Some strange filesystems like AFS return even
>		 stranger error numbers.  They cannot reasonably mean
>		 anything else so ignore those, too.  */
>	      break;
>
>	    default:
>	      /* Some other error means we found an executable file, but
>		 something went wrong executing it; return the error to our
>		 caller.  */
>	      return -1;
>	    }
>	}
>      while (*p++ != '\0');
>
>      /* We tried every element and none of them worked.  */
>      if (got_eacces)
>	/* At least one failure was due to permissions, so report that
>           error.  */
>	__set_errno (EACCES);
>
>      free (script_argv);
>      free (name - pathlen);
>      if (path_malloc)
>	free (path);
>    }
>
>  /* Return the error from the last attempt (probably ENOENT).  */
>  return -1;
>}
>libc_hidden_def (execvp)

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Attachments on bug 155246: 71266