1 /* Provide relocatable programs.
2 Copyright (C) 2003-2010 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 "relocatable.h"
49 # include "areadlink.h"
50 # define xreadlink areadlink
52 # include "xreadlink.h"
56 # define xmalloc malloc
57 # define xstrdup strdup
62 /* Declare canonicalize_file_name.
63 The <stdlib.h> included above may be the system's one, not the gnulib
65 extern char * canonicalize_file_name (const char *name);
68 ISSLASH(C) tests whether C is a directory separator character.
69 IS_PATH_WITH_DIR(P) tests whether P contains a directory specification.
71 #if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__
72 /* Win32, Cygwin, OS/2, DOS */
73 # define ISSLASH(C) ((C) == '/' || (C) == '\\')
74 # define HAS_DEVICE(P) \
75 ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \
77 # define IS_PATH_WITH_DIR(P) \
78 (strchr (P, '/') != NULL || strchr (P, '\\') != NULL || HAS_DEVICE (P))
79 # define FILE_SYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0)
82 # define ISSLASH(C) ((C) == '/')
83 # define IS_PATH_WITH_DIR(P) (strchr (P, '/') != NULL)
84 # define FILE_SYSTEM_PREFIX_LEN(P) 0
87 /* The results of open() in this file are not used with fchdir,
88 therefore save some unnecessary work in fchdir.c. */
92 /* Use the system functions, not the gnulib overrides in this file. */
96 #undef set_program_name
99 #if ENABLE_RELOCATABLE
102 /* File descriptor of the executable.
103 (Only used to verify that we find the correct executable.) */
104 static int executable_fd = -1;
107 /* Tests whether a given pathname may belong to the executable. */
109 maybe_executable (const char *filename)
111 /* Woe32 lacks the access() function, but Cygwin doesn't. */
112 #if !(defined WIN32_NATIVE && !defined __CYGWIN__)
113 if (access (filename, X_OK) < 0)
117 if (executable_fd >= 0)
119 /* If we already have an executable_fd, check that filename points to
122 struct stat statfile;
124 if (fstat (executable_fd, &statexe) >= 0)
126 if (stat (filename, &statfile) < 0)
128 if (!(statfile.st_dev
129 && statfile.st_dev == statexe.st_dev
130 && statfile.st_ino == statexe.st_ino))
140 /* Determine the full pathname of the current executable, freshly allocated.
141 Return NULL if unknown.
142 Guaranteed to work on Linux and Woe32. Likely to work on the other
143 Unixes (maybe except BeOS), under most conditions. */
145 find_executable (const char *argv0)
147 #if defined WIN32_NATIVE || defined __CYGWIN__
148 char location[MAX_PATH];
149 int length = GetModuleFileName (NULL, location, sizeof (location));
152 if (!IS_PATH_WITH_DIR (location))
153 /* Shouldn't happen. */
156 #if defined __CYGWIN__
157 /* cygwin-1.5.13 (2005-03-01) or newer would also allow a Linux-like
158 implementation: readlink of "/proc/self/exe". But using the
159 result of the Win32 system call is simpler and is consistent with the
160 code in relocatable.c. */
161 /* On Cygwin, we need to convert paths coming from Win32 system calls
162 to the Unix-like slashified notation. */
163 static char location_as_posix_path[2 * MAX_PATH];
164 /* There's no error return defined for cygwin_conv_to_posix_path.
165 See cygwin-api/func-cygwin-conv-to-posix-path.html.
166 Does it overflow the buffer of expected size MAX_PATH or does it
167 truncate the path? I don't know. Let's catch both. */
168 cygwin_conv_to_posix_path (location, location_as_posix_path);
169 location_as_posix_path[MAX_PATH - 1] = '\0';
170 if (strlen (location_as_posix_path) >= MAX_PATH - 1)
171 /* A sign of buffer overflow or path truncation. */
173 /* Call canonicalize_file_name, because Cygwin supports symbolic links. */
174 return canonicalize_file_name (location_as_posix_path);
176 return xstrdup (location);
179 #else /* Unix && !Cygwin */
181 /* The executable is accessible as /proc/<pid>/exe. In newer Linux
182 versions, also as /proc/self/exe. Linux >= 2.1 provides a symlink
183 to the true pathname; older Linux versions give only device and ino,
184 enclosed in brackets, which we cannot use here. */
188 link = xreadlink ("/proc/self/exe");
189 if (link != NULL && link[0] != '[')
191 if (executable_fd < 0)
192 executable_fd = open ("/proc/self/exe", O_RDONLY, 0);
196 sprintf (buf, "/proc/%d/exe", getpid ());
197 link = xreadlink (buf);
198 if (link != NULL && link[0] != '[')
200 if (executable_fd < 0)
201 executable_fd = open (buf, O_RDONLY, 0);
205 #if HAVE_MACH_O_DYLD_H && HAVE__NSGETEXECUTABLEPATH
206 /* On MacOS X 10.2 or newer, the function
207 int _NSGetExecutablePath (char *buf, uint32_t *bufsize);
208 can be used to retrieve the executable's full path. */
210 unsigned int length = sizeof (location);
211 if (_NSGetExecutablePath (location, &length) == 0
212 && location[0] == '/')
213 return canonicalize_file_name (location);
215 /* Guess the executable's full path. We assume the executable has been
216 called via execlp() or execvp() with properly set up argv[0]. The
217 login(1) convention to add a '-' prefix to argv[0] is not supported. */
219 bool has_slash = false;
222 for (p = argv0; *p; p++)
231 /* exec searches paths without slashes in the directory list given
233 const char *path = getenv ("PATH");
240 for (p = path; *p; p = p_next)
250 p_next = (*q == '\0' ? q : q + 1);
252 /* We have a path item at p, of length p_len.
253 Now concatenate the path item and argv0. */
254 concat_name = (char *) xmalloc (p_len + strlen (argv0) + 2);
256 if (concat_name == NULL)
260 /* An empty PATH element designates the current directory. */
261 strcpy (concat_name, argv0);
264 memcpy (concat_name, p, p_len);
265 concat_name[p_len] = '/';
266 strcpy (concat_name + p_len + 1, argv0);
268 if (maybe_executable (concat_name))
269 return canonicalize_file_name (concat_name);
273 /* Not found in the PATH, assume the current directory. */
275 /* exec treats paths containing slashes as relative to the current
277 if (maybe_executable (argv0))
278 return canonicalize_file_name (argv0);
280 /* No way to find the executable. */
285 /* Full pathname of executable, or NULL. */
286 static char *executable_fullname;
289 prepare_relocate (const char *orig_installprefix, const char *orig_installdir,
294 /* Determine the full pathname of the current executable. */
295 executable_fullname = find_executable (argv0);
297 /* Determine the current installation prefix from it. */
298 curr_prefix = compute_curr_prefix (orig_installprefix, orig_installdir,
299 executable_fullname);
300 if (curr_prefix != NULL)
302 /* Now pass this prefix to all copies of the relocate.c source file. */
303 set_relocation_prefix (orig_installprefix, curr_prefix);
309 /* Set program_name, based on argv[0], and original installation prefix and
310 directory, for relocatability. */
312 set_program_name_and_installdir (const char *argv0,
313 const char *orig_installprefix,
314 const char *orig_installdir)
316 const char *argv0_stripped = argv0;
318 /* Relocatable programs are renamed to .bin by install-reloc. Or, more
319 generally, their suffix is changed from $exeext to .bin$exeext.
320 Remove the ".bin" here. */
322 size_t argv0_len = strlen (argv0);
323 const size_t exeext_len = sizeof (EXEEXT) - sizeof ("");
324 if (argv0_len > 4 + exeext_len)
325 if (memcmp (argv0 + argv0_len - exeext_len - 4, ".bin", 4) == 0)
327 if (sizeof (EXEEXT) > sizeof (""))
329 /* Compare using an inlined copy of c_strncasecmp(), because
330 the filenames may have undergone a case conversion since
331 they were packaged. In other words, EXEEXT may be ".exe"
332 on one system and ".EXE" on another. */
333 static const char exeext[] = EXEEXT;
334 const char *s1 = argv0 + argv0_len - exeext_len;
335 const char *s2 = exeext;
336 for (; *s1 != '\0'; s1++, s2++)
338 unsigned char c1 = *s1;
339 unsigned char c2 = *s2;
340 if ((c1 >= 'A' && c1 <= 'Z' ? c1 - 'A' + 'a' : c1)
341 != (c2 >= 'A' && c2 <= 'Z' ? c2 - 'A' + 'a' : c2))
345 /* Remove ".bin" before EXEEXT or its equivalent. */
347 char *shorter = (char *) xmalloc (argv0_len - 4 + 1);
352 memcpy (shorter, argv0, argv0_len - exeext_len - 4);
353 if (sizeof (EXEEXT) > sizeof (""))
354 memcpy (shorter + argv0_len - exeext_len - 4,
355 argv0 + argv0_len - exeext_len - 4,
357 shorter[argv0_len - 4] = '\0';
358 argv0_stripped = shorter;
365 set_program_name (argv0_stripped);
367 prepare_relocate (orig_installprefix, orig_installdir, argv0);
370 /* Return the full pathname of the current executable, based on the earlier
371 call to set_program_name_and_installdir. Return NULL if unknown. */
373 get_full_program_name (void)
375 return executable_fullname;