1 /* Relocating wrapper program.
2 Copyright (C) 2003, 2005-2007, 2009-2021 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 3 of the License, or
8 (at your option) 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, see <https://www.gnu.org/licenses/>. */
17
18 /* Dependencies:
19 relocwrapper
20 -> progname
21 -> progreloc
22 -> stat
23 -> filename
24 -> pathmax
25 -> verify
26 -> areadlink
27 -> careadlinkat
28 -> allocator
29 -> readlink
30 -> stat
31 -> canonicalize-lgpl
32 -> libc-config
33 -> errno
34 -> fcntl-h
35 -> stdbool
36 -> sys_stat
37 -> unistd
38 -> eloop-threshold
39 -> filename
40 -> idx
41 -> intprops
42 -> scratch_buffer
43 -> malloc-posix
44 -> realloc-posix
45 -> free-posix
46 -> pathmax
47 -> mempcpy
48 -> rawmemchr
49 -> readlink
50 -> stat
51 -> double-slash-root
52 -> relocatable
53 -> setenv
54 -> malloca
55 -> fprintf-posix [ignore, cut dependency tree here]
56 -> strerror [ignore, cut dependency tree here]
57 -> c-ctype
58
59 Macros that need to be set while compiling this file:
60 - ENABLE_RELOCATABLE 1
61 - INSTALLPREFIX the base installation directory
62 - INSTALLDIR the directory into which this program is installed
63 - LIBPATHVAR the platform dependent runtime library path variable
64 - LIBDIRS a comma-terminated list of strings representing the list of
65 directories that contain the libraries at installation time
66
67 We don't want to internationalize this wrapper because then it would
68 depend on libintl and therefore need relocation itself. So use only
69 libc functions, no gettext(), no error(), no xmalloc(), no xsetenv().
70 */
71
72 #define _GL_USE_STDLIB_ALLOC 1
73 #include <config.h>
74
75 #include <stdio.h>
76 #include <stdlib.h>
77 #include <string.h>
78 #include <unistd.h>
79 #include <errno.h>
80
81 #include "progname.h"
82 #include "relocatable.h"
83 #include "c-ctype.h"
84 #include "verify.h"
85
86 /* Use the system functions, not the gnulib overrides in this file. */
87 #undef fprintf
88 #undef strerror
89
90 /* Return a copy of the filename, with an extra ".bin" at the end.
91 More generally, it replaces "${EXEEXT}" at the end with ".bin${EXEEXT}". */
92 static char *
93 add_dotbin (const char *filename)
94 {
95 size_t filename_len = strlen (filename);
96 char *result = (char *) malloc (filename_len + 4 + 1);
97
98 if (result != NULL)
99 {
100 if (sizeof (EXEEXT) > sizeof (""))
101 {
102 /* EXEEXT handling. */
103 const size_t exeext_len = sizeof (EXEEXT) - sizeof ("");
104 static const char exeext[] = EXEEXT;
105 if (filename_len > exeext_len)
106 {
107 /* Compare using an inlined copy of c_strncasecmp(), because
108 the filenames may have undergone a case conversion since
109 they were packaged. In other words, EXEEXT may be ".exe"
110 on one system and ".EXE" on another. */
111 const char *s1 = filename + filename_len - exeext_len;
112 const char *s2 = exeext;
113 for (; *s1 != '\0'; s1++, s2++)
114 {
115 unsigned char c1 = *s1;
116 unsigned char c2 = *s2;
117 if (c_tolower (c1) != c_tolower (c2))
118 goto simple_append;
119 }
120 /* Insert ".bin" before EXEEXT or its equivalent. */
121 memcpy (result, filename, filename_len - exeext_len);
122 memcpy (result + filename_len - exeext_len, ".bin", 4);
123 memcpy (result + filename_len - exeext_len + 4,
124 filename + filename_len - exeext_len,
125 exeext_len + 1);
126 return result;
127 }
128 }
129 simple_append:
130 /* Simply append ".bin". */
131 memcpy (result, filename, filename_len);
132 memcpy (result + filename_len, ".bin", 4 + 1);
133 return result;
134 }
135 else
136 {
137 fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
138 exit (1);
139 }
140 }
141
142 /* List of directories that contain the libraries. */
143 static const char *libdirs[] = { LIBDIRS NULL };
144 /* Verify that at least one directory is given. */
145 verify (sizeof (libdirs) / sizeof (libdirs[0]) > 1);
146
147 /* Relocate the list of directories that contain the libraries. */
148 static void
149 relocate_libdirs ()
150 {
151 size_t i;
152
153 for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
154 libdirs[i] = relocate (libdirs[i]);
155 }
156
157 /* Activate the list of directories in the LIBPATHVAR. */
158 static void
159 activate_libdirs ()
160 {
161 const char *old_value;
162 size_t total;
163 size_t i;
164 char *value;
165 char *p;
166
167 old_value = getenv (LIBPATHVAR);
168 if (old_value == NULL)
169 old_value = "";
170
171 total = 0;
172 for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
173 total += strlen (libdirs[i]) + 1;
174 total += strlen (old_value) + 1;
175
176 value = (char *) malloc (total);
177 if (value == NULL)
178 {
179 fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
180 exit (1);
181 }
182 p = value;
183 for (i = 0; i < sizeof (libdirs) / sizeof (libdirs[0]) - 1; i++)
184 {
185 size_t len = strlen (libdirs[i]);
186 memcpy (p, libdirs[i], len);
187 p += len;
188 *p++ = ':';
189 }
190 if (old_value[0] != '\0')
191 strcpy (p, old_value);
192 else
193 p[-1] = '\0';
194
195 if (setenv (LIBPATHVAR, value, 1) < 0)
196 {
197 fprintf (stderr, "%s: %s\n", program_name, "memory exhausted");
198 exit (1);
199 }
200 }
201
202 int
203 main (int argc, char *argv[])
204 {
205 char *full_program_name;
206
207 /* Set the program name and perform preparations for
208 get_full_program_name() and relocate(). */
209 set_program_name_and_installdir (argv[0], INSTALLPREFIX, INSTALLDIR);
210
211 /* Get the full program path. (Important if accessed through a symlink.) */
212 full_program_name = get_full_program_name ();
213 if (full_program_name == NULL)
214 full_program_name = argv[0];
215
216 /* Invoke the real program, with suffix ".bin". */
217 argv[0] = add_dotbin (full_program_name);
218 relocate_libdirs ();
219 activate_libdirs ();
220 execv (argv[0], argv);
221 fprintf (stderr, "%s: could not execute %s: %s\n",
222 program_name, argv[0], strerror (errno));
223 exit (127);
224 }