1/* Relocating wrapper program.
2   Copyright (C) 2003, 2005-2006 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#include <config.h>
46
47#include <stdio.h>
48#include <stdlib.h>
49#include <string.h>
50#if HAVE_UNISTD_H
51# include <unistd.h>
52#endif
53#include <errno.h>
54
55#include "progname.h"
56#include "relocatable.h"
57#include "setenv.h"
58
59/* Return a copy of the filename, with an extra ".bin" at the end.
60   More generally, it replaces "${EXEEXT}" at the end with ".bin${EXEEXT}".  */
61static char *
62add_dotbin (const char *filename)
63{
64  size_t filename_len = strlen (filename);
65  char *result = (char *) malloc (filename_len + 4 + 1);
66
67  if (result != NULL)
68    {
69      if (sizeof (EXEEXT) > sizeof (""))
70	{
71	  /* EXEEXT handling.  */
72	  const size_t exeext_len = sizeof (EXEEXT) - sizeof ("");
73	  static const char exeext[] = EXEEXT;
74	  if (filename_len > exeext_len)
75	    {
76	      /* Compare using an inlined copy of c_strncasecmp(), because
77		 the filenames may have undergone a case conversion since
78		 they were packaged.  In other words, EXEEXT may be ".exe"
79		 on one system and ".EXE" on another.  */
80	      const char *s1 = filename + filename_len - exeext_len;
81	      const char *s2 = exeext;
82	      for (; *s1 != '\0'; s1++, s2++)
83		{
84		  unsigned char c1 = *s1;
85		  unsigned char c2 = *s2;
86		  if ((c1 >= 'A' && c1 <= 'Z' ? c1 - 'A' + 'a' : c1)
87		      != (c2 >= 'A' && c2 <= 'Z' ? c2 - 'A' + 'a' : c2))
88		    goto simple_append;
89		}
90	      /* Insert ".bin" before EXEEXT or its equivalent.  */
91	      memcpy (result, filename, filename_len - exeext_len);
92	      memcpy (result + filename_len - exeext_len, ".bin", 4);
93	      memcpy (result + filename_len - exeext_len + 4,
94		      filename + filename_len - exeext_len,
95		      exeext_len + 1);
96	      return result;
97	    }
98	}
99     simple_append:
100      /* Simply append ".bin".  */
101      memcpy (result, filename, filename_len);
102      memcpy (result + filename_len, ".bin", 4 + 1);
103      return result;
104    }
105  else
106    {
107      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
108      exit (1);
109    }
110}
111
112/* List of directories that contain the libraries.  */
113static const char *libdirs[] = { LIBDIRS NULL };
114/* Verify that at least one directory is given.  */
115typedef int verify1[2 * (sizeof (libdirs) / sizeof (libdirs[0]) > 1) - 1];
116
117/* Relocate the list of directories that contain the libraries.  */
118static void
119relocate_libdirs ()
120{
121  size_t i;
122
123  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
124    libdirs[i] = relocate (libdirs[i]);
125}
126
127/* Activate the list of directories in the LIBPATHVAR.  */
128static void
129activate_libdirs ()
130{
131  const char *old_value;
132  size_t total;
133  size_t i;
134  char *value;
135  char *p;
136
137  old_value = getenv (LIBPATHVAR);
138  if (old_value == NULL)
139    old_value = "";
140
141  total = 0;
142  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
143    total += strlen (libdirs[i]) + 1;
144  total += strlen (old_value) + 1;
145
146  value = (char *) malloc (total);
147  if (value == NULL)
148    {
149      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
150      exit (1);
151    }
152  p = value;
153  for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
154    {
155      size_t len = strlen (libdirs[i]);
156      memcpy (p, libdirs[i], len);
157      p += len;
158      *p++ = ':';
159    }
160  if (old_value[0] != '\0')
161    strcpy (p, old_value);
162  else
163    p[-1] = '\0';
164
165  if (setenv (LIBPATHVAR, value, 1) < 0)
166    {
167      fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
168      exit (1);
169    }
170}
171
172int
173main (int argc, char *argv[])
174{
175  char *full_program_name;
176
177  /* Set the program name and perform preparations for
178     get_full_program_name() and relocate().  */
179  set_program_name_and_installdir (argv[0], INSTALLPREFIX, INSTALLDIR);
180
181  /* Get the full program path.  (Important if accessed through a symlink.)  */
182  full_program_name = get_full_program_name ();
183  if (full_program_name == NULL)
184    full_program_name = argv[0];
185
186  /* Invoke the real program, with suffix ".bin".  */
187  argv[0] = add_dotbin (full_program_name);
188  relocate_libdirs ();
189  activate_libdirs ();
190  execv (argv[0], argv);
191  fprintf (stderr, "%s: could not execute %s: %s\n",
192	   program_name, argv[0], strerror (errno));
193  exit (127);
194}
195