1/* Relocating wrapper program.
2   Copyright (C) 2003, 2005 Free Software Foundation, Inc.
3   Written by Bruno Haible <bruno@clisp.org>, 2003.
4
5   This program is free software; you can redistribute it and/or modify
6   it under the terms of the GNU General Public License as published by
7   the Free Software Foundation; either version 2, or (at your option)
8   any later version.
9
10   This program is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   GNU General Public License for more details.
14
15   You should have received a copy of the GNU General Public License
16   along with this program; if not, write to the Free Software Foundation,
17   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
18
19/* Dependencies:
20   relocwrapper
21    -> progname
22    -> progreloc
23        -> xreadlink
24           -> readlink
25        -> canonicalize
26           -> allocsa
27    -> relocatable
28    -> setenv
29       -> allocsa
30    -> strerror
31
32   Macros that need to be set while compiling this file:
33     - ENABLE_RELOCATABLE 1
34     - INSTALLPREFIX the base installation directory
35     - INSTALLDIR the directory into which this program is installed
36     - LIBPATHVAR the platform dependent runtime library path variable
37     - LIBDIRS a comma-terminated list of strings representing the list of
38       directories that contain the libraries at installation time
39
40   We don't want to internationalize this wrapper because then it would
41   depend on libintl and therefore need relocation itself.  So use only
42   libc functions, no gettext(), no error(), no xmalloc(), no xsetenv().
43 */
44
45#ifdef HAVE_CONFIG_H
46# include <config.h>
47#endif
48
49#include <stdio.h>
50#include <stdlib.h>
51#include <string.h>
52#if HAVE_UNISTD_H
53# include <unistd.h>
54#endif
55#include <errno.h>
56
57#include "progname.h"
58#include "relocatable.h"
59#include "setenv.h"
60
61/* Return a copy of the filename, with an extra ".bin" at the end.
62   More generally, it replaces "${EXEEXT}" at the end with ".bin${EXEEXT}".  */
63static char *
64add_dotbin (const char *filename)
65{
66  size_t filename_len = strlen (filename);
67  char *result = (char *) malloc (filename_len + 4 + 1);
68
69  if (result != NULL)
70    {
71      if (sizeof (EXEEXT) > sizeof (""))
72	{
73	  /* EXEEXT handling.  */
74	  const size_t exeext_len = sizeof (EXEEXT) - sizeof ("");
75	  static const char exeext[] = EXEEXT;
76	  if (filename_len > exeext_len)
77	    {
78	      /* Compare using an inlined copy of c_strncasecmp(), because
79		 the filenames may have undergone a case conversion since
80		 they were packaged.  In other words, EXEEXT may be ".exe"
81		 on one system and ".EXE" on another.  */
82	      const char *s1 = filename + filename_len - exeext_len;
83	      const char *s2 = exeext;
84	      for (; *s1 != '\0'; s1++, s2++)
85		{
86		  unsigned char c1 = *s1;
87		  unsigned char c2 = *s2;
88		  if ((c1 >= 'A' && c1 <= 'Z' ? c1 - 'A' + 'a' : c1)
89		      != (c2 >= 'A' && c2 <= 'Z' ? c2 - 'A' + 'a' : c2))
90		    goto simple_append;
91		}
92	      /* Insert ".bin" before EXEEXT or its equivalent.  */
93	      memcpy (result, filename, filename_len - exeext_len);
94	      memcpy (result + filename_len - exeext_len, ".bin", 4);
95	      memcpy (result + filename_len - exeext_len + 4,
96		      filename + filename_len - exeext_len,
97		      exeext_len + 1);
98	      return result;
99	    }
100	}
101     simple_append:
102      /* Simply append ".bin".  */
103      memcpy (result, filename, filename_len);
104      memcpy (result + filename_len, ".bin", 4 + 1);
105      return result;
106    }
107  else
108    {
109      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
110      exit (1);
111    }
112}
113
114/* List of directories that contain the libraries.  */
115static const char *libdirs[] = { LIBDIRS NULL };
116/* Verify that at least one directory is given.  */
117typedef int verify1[2 * (sizeof (libdirs) / sizeof (libdirs[0]) > 1) - 1];
118
119/* Relocate the list of directories that contain the libraries.  */
120static void
121relocate_libdirs ()
122{
123  size_t i;
124
125  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
126    libdirs[i] = relocate (libdirs[i]);
127}
128
129/* Activate the list of directories in the LIBPATHVAR.  */
130static void
131activate_libdirs ()
132{
133  const char *old_value;
134  size_t total;
135  size_t i;
136  char *value;
137  char *p;
138
139  old_value = getenv (LIBPATHVAR);
140  if (old_value == NULL)
141    old_value = "";
142
143  total = 0;
144  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
145    total += strlen (libdirs[i]) + 1;
146  total += strlen (old_value) + 1;
147
148  value = (char *) malloc (total);
149  if (value == NULL)
150    {
151      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
152      exit (1);
153    }
154  p = value;
155  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
156    {
157      size_t len = strlen (libdirs[i]);
158      memcpy (p, libdirs[i], len);
159      p += len;
160      *p++ = ':';
161    }
162  if (old_value[0] != '\0')
163    strcpy (p, old_value);
164  else
165    p[-1] = '\0';
166
167  if (setenv (LIBPATHVAR, value, 1) < 0)
168    {
169      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
170      exit (1);
171    }
172}
173
174int
175main (int argc, char *argv[])
176{
177  char *full_program_name;
178
179  /* Set the program name and perform preparations for
180     get_full_program_name() and relocate().  */
181  set_program_name_and_installdir (argv[0], INSTALLPREFIX, INSTALLDIR);
182
183  /* Get the full program path.  (Important if accessed through a symlink.)  */
184  full_program_name = get_full_program_name ();
185  if (full_program_name == NULL)
186    full_program_name = argv[0];
187
188  /* Invoke the real program, with suffix ".bin".  */
189  argv[0] = add_dotbin (full_program_name);
190  relocate_libdirs ();
191  activate_libdirs ();
192  execv (argv[0], argv);
193  fprintf (stderr, "%s: could not execute %s: %s\n",
194	   program_name, argv[0], strerror (errno));
195  exit (127);
196}
197