1 /* Provide relocatable programs.
2 Copyright (C) 2003-2006 Free Software Foundation, Inc.
3 Written by Bruno Haible <bruno@clisp.org>, 2003.
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.
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.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
32 /* Get declaration of _NSGetExecutablePath on MacOS X 10.2 or newer. */
33 #if HAVE_MACH_O_DYLD_H
34 # include <mach-o/dyld.h>
37 #if defined _WIN32 || defined __WIN32__
41 #if defined WIN32_NATIVE || defined __CYGWIN__
42 # define WIN32_LEAN_AND_MEAN
46 #include "xreadlink.h"
47 #include "canonicalize.h"
48 #include "relocatable.h"
51 # define xmalloc malloc
52 # define xstrdup strdup
58 ISSLASH(C) tests whether C is a directory separator character.
59 IS_PATH_WITH_DIR(P) tests whether P contains a directory specification.
61 #if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__
62 /* Win32, Cygwin, OS/2, DOS */
63 # define ISSLASH(C) ((C) == '/' || (C) == '\\')
64 # define HAS_DEVICE(P) \
65 ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \
67 # define IS_PATH_WITH_DIR(P) \
68 (strchr (P, '/') != NULL || strchr (P, '\\') != NULL || HAS_DEVICE (P))
69 # define FILE_SYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0)
72 # define ISSLASH(C) ((C) == '/')
73 # define IS_PATH_WITH_DIR(P) (strchr (P, '/') != NULL)
74 # define FILE_SYSTEM_PREFIX_LEN(P) 0
77 /* The results of open() in this file are not used with fchdir,
78 therefore save some unnecessary work in fchdir.c. */
82 #undef set_program_name
85 #if ENABLE_RELOCATABLE
88 /* File descriptor of the executable.
89 (Only used to verify that we find the correct executable.) */
90 static int executable_fd = -1;
93 /* Tests whether a given pathname may belong to the executable. */
95 maybe_executable (const char *filename)
97 /* Woe32 lacks the access() function, but Cygwin doesn't. */
98 #if !(defined WIN32_NATIVE && !defined __CYGWIN__)
99 if (access (filename, X_OK) < 0)
103 if (executable_fd >= 0)
105 /* If we already have an executable_fd, check that filename points to
108 struct stat statfile;
110 if (fstat (executable_fd, &statexe) >= 0)
112 if (stat (filename, &statfile) < 0)
114 if (!(statfile.st_dev
115 && statfile.st_dev == statexe.st_dev
116 && statfile.st_ino == statexe.st_ino))
126 /* Determine the full pathname of the current executable, freshly allocated.
127 Return NULL if unknown.
128 Guaranteed to work on Linux and Woe32. Likely to work on the other
129 Unixes (maybe except BeOS), under most conditions. */
131 find_executable (const char *argv0)
133 #if defined WIN32_NATIVE || defined __CYGWIN__
134 char location[MAX_PATH];
135 int length = GetModuleFileName (NULL, location, sizeof (location));
138 if (!IS_PATH_WITH_DIR (location))
139 /* Shouldn't happen. */
142 #if defined __CYGWIN__
143 /* cygwin-1.5.13 (2005-03-01) or newer would also allow a Linux-like
144 implementation: readlink of "/proc/self/exe". But using the
145 result of the Win32 system call is simpler and is consistent with the
146 code in relocatable.c. */
147 /* On Cygwin, we need to convert paths coming from Win32 system calls
148 to the Unix-like slashified notation. */
149 static char location_as_posix_path[2 * MAX_PATH];
150 /* There's no error return defined for cygwin_conv_to_posix_path.
151 See cygwin-api/func-cygwin-conv-to-posix-path.html.
152 Does it overflow the buffer of expected size MAX_PATH or does it
153 truncate the path? I don't know. Let's catch both. */
154 cygwin_conv_to_posix_path (location, location_as_posix_path);
155 location_as_posix_path[MAX_PATH - 1] = '\0';
156 if (strlen (location_as_posix_path) >= MAX_PATH - 1)
157 /* A sign of buffer overflow or path truncation. */
159 /* Call canonicalize_file_name, because Cygwin supports symbolic links. */
160 return canonicalize_file_name (location_as_posix_path);
162 return xstrdup (location);
165 #else /* Unix && !Cygwin */
167 /* The executable is accessible as /proc/<pid>/exe. In newer Linux
168 versions, also as /proc/self/exe. Linux >= 2.1 provides a symlink
169 to the true pathname; older Linux versions give only device and ino,
170 enclosed in brackets, which we cannot use here. */
174 link = xreadlink ("/proc/self/exe");
175 if (link != NULL && link[0] != '[')
177 if (executable_fd < 0)
178 executable_fd = open ("/proc/self/exe", O_RDONLY, 0);
182 sprintf (buf, "/proc/%d/exe", getpid ());
183 link = xreadlink (buf);
184 if (link != NULL && link[0] != '[')
186 if (executable_fd < 0)
187 executable_fd = open (buf, O_RDONLY, 0);
191 #if HAVE_MACH_O_DYLD_H && HAVE__NSGETEXECUTABLEPATH
192 /* On MacOS X 10.2 or newer, the function
193 int _NSGetExecutablePath (char *buf, unsigned long *bufsize);
194 can be used to retrieve the executable's full path. */
196 unsigned long length = sizeof (location);
197 if (_NSGetExecutablePath (location, &length) == 0
198 && location[0] == '/')
199 return canonicalize_file_name (location);
201 /* Guess the executable's full path. We assume the executable has been
202 called via execlp() or execvp() with properly set up argv[0]. The
203 login(1) convention to add a '-' prefix to argv[0] is not supported. */
205 bool has_slash = false;
208 for (p = argv0; *p; p++)
217 /* exec searches paths without slashes in the directory list given
219 const char *path = getenv ("PATH");
226 for (p = path; *p; p = p_next)
236 p_next = (*q == '\0' ? q : q + 1);
238 /* We have a path item at p, of length p_len.
239 Now concatenate the path item and argv0. */
240 concat_name = (char *) xmalloc (p_len + strlen (argv0) + 2);
242 if (concat_name == NULL)
246 /* An empty PATH element designates the current directory. */
247 strcpy (concat_name, argv0);
250 memcpy (concat_name, p, p_len);
251 concat_name[p_len] = '/';
252 strcpy (concat_name + p_len + 1, argv0);
254 if (maybe_executable (concat_name))
255 return canonicalize_file_name (concat_name);
259 /* Not found in the PATH, assume the current directory. */
261 /* exec treats paths containing slashes as relative to the current
263 if (maybe_executable (argv0))
264 return canonicalize_file_name (argv0);
266 /* No way to find the executable. */
271 /* Full pathname of executable, or NULL. */
272 static char *executable_fullname;
275 prepare_relocate (const char *orig_installprefix, const char *orig_installdir,
278 const char *curr_prefix;
280 /* Determine the full pathname of the current executable. */
281 executable_fullname = find_executable (argv0);
283 /* Determine the current installation prefix from it. */
284 curr_prefix = compute_curr_prefix (orig_installprefix, orig_installdir,
285 executable_fullname);
286 if (curr_prefix != NULL)
287 /* Now pass this prefix to all copies of the relocate.c source file. */
288 set_relocation_prefix (orig_installprefix, curr_prefix);
291 /* Set program_name, based on argv[0], and original installation prefix and
292 directory, for relocatability. */
294 set_program_name_and_installdir (const char *argv0,
295 const char *orig_installprefix,
296 const char *orig_installdir)
298 const char *argv0_stripped = argv0;
300 /* Relocatable programs are renamed to .bin by install-reloc. Or, more
301 generally, their suffix is changed from $exeext to .bin$exeext.
302 Remove the ".bin" here. */
304 size_t argv0_len = strlen (argv0);
305 const size_t exeext_len = sizeof (EXEEXT) - sizeof ("");
306 if (argv0_len > 4 + exeext_len)
307 if (memcmp (argv0 + argv0_len - exeext_len - 4, ".bin", 4) == 0)
309 if (sizeof (EXEEXT) > sizeof (""))
311 /* Compare using an inlined copy of c_strncasecmp(), because
312 the filenames may have undergone a case conversion since
313 they were packaged. In other words, EXEEXT may be ".exe"
314 on one system and ".EXE" on another. */
315 static const char exeext[] = EXEEXT;
316 const char *s1 = argv0 + argv0_len - exeext_len;
317 const char *s2 = exeext;
318 for (; *s1 != '\0'; s1++, s2++)
320 unsigned char c1 = *s1;
321 unsigned char c2 = *s2;
322 if ((c1 >= 'A' && c1 <= 'Z' ? c1 - 'A' + 'a' : c1)
323 != (c2 >= 'A' && c2 <= 'Z' ? c2 - 'A' + 'a' : c2))
327 /* Remove ".bin" before EXEEXT or its equivalent. */
329 char *shorter = (char *) xmalloc (argv0_len - 4 + 1);
334 memcpy (shorter, argv0, argv0_len - exeext_len - 4);
335 if (sizeof (EXEEXT) > sizeof (""))
336 memcpy (shorter + argv0_len - exeext_len - 4,
337 argv0 + argv0_len - exeext_len - 4,
339 shorter[argv0_len - 4] = '\0';
340 argv0_stripped = shorter;
347 set_program_name (argv0_stripped);
349 prepare_relocate (orig_installprefix, orig_installdir, argv0);
352 /* Return the full pathname of the current executable, based on the earlier
353 call to set_program_name_and_installdir. Return NULL if unknown. */
355 get_full_program_name (void)
357 return executable_fullname;