/* Relocating wrapper program.

   Copyright (C) 2003, 2005-2007, 2009-2015 Free Software Foundation, Inc.

   Written by Bruno Haible <bruno@clisp.org>, 2003.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Dependencies:

   relocwrapper

    -> progname

    -> progreloc

        -> areadlink

           -> careadlinkat

             -> allocator

           -> readlink

        -> canonicalize-lgpl

           -> malloca

           -> readlink

    -> relocatable

    -> setenv

       -> malloca

    -> c-ctype

   Macros that need to be set while compiling this file:

     - ENABLE_RELOCATABLE 1

     - INSTALLPREFIX the base installation directory

     - INSTALLDIR the directory into which this program is installed

     - LIBPATHVAR the platform dependent runtime library path variable

     - LIBDIRS a comma-terminated list of strings representing the list of

       directories that contain the libraries at installation time

   We don't want to internationalize this wrapper because then it would

   depend on libintl and therefore need relocation itself.  So use only

   libc functions, no gettext(), no error(), no xmalloc(), no xsetenv().

 */

#define _GL_USE_STDLIB_ALLOC 1

#include <config.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <errno.h>

#include "progname.h"

#include "relocatable.h"

#include "c-ctype.h"

#include "verify.h"

/* Use the system functions, not the gnulib overrides in this file.  */

#undef fprintf

/* Return a copy of the filename, with an extra ".bin" at the end.

   More generally, it replaces "${EXEEXT}" at the end with ".bin${EXEEXT}".  */

static char *

add_dotbin (const char *filename)

{

  size_t filename_len = strlen (filename);

  char *result = (char *) malloc (filename_len + 4 + 1);

  if (result != NULL)

    {

      if (sizeof (EXEEXT) > sizeof (""))

        {

          /* EXEEXT handling.  */

          const size_t exeext_len = sizeof (EXEEXT) - sizeof ("");

          static const char exeext[] = EXEEXT;

          if (filename_len > exeext_len)

            {

              /* Compare using an inlined copy of c_strncasecmp(), because

                 the filenames may have undergone a case conversion since

                 they were packaged.  In other words, EXEEXT may be ".exe"

                 on one system and ".EXE" on another.  */

              const char *s1 = filename + filename_len - exeext_len;

              const char *s2 = exeext;

              for (; *s1 != '\0'; s1++, s2++)

                {

                  unsigned char c1 = *s1;

                  unsigned char c2 = *s2;

                  if (c_tolower (c1) != c_tolower (c2))

                    goto simple_append;

                }

              /* Insert ".bin" before EXEEXT or its equivalent.  */

              memcpy (result, filename, filename_len - exeext_len);

              memcpy (result + filename_len - exeext_len, ".bin", 4);

              memcpy (result + filename_len - exeext_len + 4,

                      filename + filename_len - exeext_len,

                      exeext_len + 1);

              return result;

            }

        }

     simple_append:

      /* Simply append ".bin".  */

      memcpy (result, filename, filename_len);

      memcpy (result + filename_len, ".bin", 4 + 1);

      return result;

    }

  else

    {

      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");

      exit (1);

    }

}

/* List of directories that contain the libraries.  */

static const char *libdirs[] = { LIBDIRS NULL };

/* Verify that at least one directory is given.  */

verify (sizeof (libdirs) / sizeof (libdirs[0]) > 1);

/* Relocate the list of directories that contain the libraries.  */

static void

relocate_libdirs ()

{

  size_t i;

  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)

    libdirs[i] = relocate (libdirs[i]);

}

/* Activate the list of directories in the LIBPATHVAR.  */

static void

activate_libdirs ()

{

  const char *old_value;

  size_t total;

  size_t i;

  char *value;

  char *p;

  old_value = getenv (LIBPATHVAR);

  if (old_value == NULL)

    old_value = "";

  total = 0;

  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)

    total += strlen (libdirs[i]) + 1;

  total += strlen (old_value) + 1;

  value = (char *) malloc (total);

  if (value == NULL)

    {

      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");

      exit (1);

    }

  p = value;

  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)

    {

      size_t len = strlen (libdirs[i]);

      memcpy (p, libdirs[i], len);

      p += len;

      *p++ = ':';

    }

  if (old_value[0] != '\0')

    strcpy (p, old_value);

  else

    p[-1] = '\0';

  if (setenv (LIBPATHVAR, value, 1) < 0)

    {

      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");

      exit (1);

    }

}

int

main (int argc, char *argv[])

{

  char *full_program_name;

  /* Set the program name and perform preparations for

     get_full_program_name() and relocate().  */

  set_program_name_and_installdir (argv[0], INSTALLPREFIX, INSTALLDIR);

  /* Get the full program path.  (Important if accessed through a symlink.)  */

  full_program_name = get_full_program_name ();

  if (full_program_name == NULL)

    full_program_name = argv[0];

  /* Invoke the real program, with suffix ".bin".  */

  argv[0] = add_dotbin (full_program_name);

  relocate_libdirs ();

  activate_libdirs ();

  execv (argv[0], argv);

  fprintf (stderr, "%s: could not execute %s: %s\n",

           program_name, argv[0], strerror (errno));

  exit (127);

}