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}".  */
61 static char *
add_dotbin(const char * filename)62 add_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.  */
113 static const char *libdirs[] = { LIBDIRS NULL };
114 /* Verify that at least one directory is given.  */
115 typedef int verify1[2 * (sizeof (libdirs) / sizeof (libdirs[0]) > 1) - 1];
116 
117 /* Relocate the list of directories that contain the libraries.  */
118 static void
relocate_libdirs()119 relocate_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.  */
128 static void
activate_libdirs()129 activate_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 
172 int
main(int argc,char * argv[])173 main (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