1 /* Provide relocatable programs.
2 Copyright (C) 2003-2017 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 <https://www.gnu.org/licenses/>. */
19 #define _GL_USE_STDLIB_ALLOC 1
33 /* Get declaration of _NSGetExecutablePath on Mac OS X 10.2 or newer. */
34 #if HAVE_MACH_O_DYLD_H
35 # include <mach-o/dyld.h>
38 #if (defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__
39 # define WINDOWS_NATIVE
43 # define WIN32_LEAN_AND_MEAN
52 #include "relocatable.h"
55 # include "areadlink.h"
56 # define xreadlink areadlink
58 # include "xreadlink.h"
62 # define xmalloc malloc
63 # define xstrdup strdup
69 # define O_EXEC O_RDONLY /* This is often close enough in older systems. */
72 /* Declare canonicalize_file_name.
73 The <stdlib.h> included above may be the system's one, not the gnulib
75 extern char * canonicalize_file_name (const char *name
);
78 ISSLASH(C) tests whether C is a directory separator character.
79 IS_PATH_WITH_DIR(P) tests whether P contains a directory specification.
81 #if ((defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__) || defined __EMX__ || defined __DJGPP__
82 /* Native Windows, OS/2, DOS */
83 # define ISSLASH(C) ((C) == '/' || (C) == '\\')
84 # define HAS_DEVICE(P) \
85 ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \
87 # define IS_PATH_WITH_DIR(P) \
88 (strchr (P, '/') != NULL || strchr (P, '\\') != NULL || HAS_DEVICE (P))
89 # define FILE_SYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0)
92 # define ISSLASH(C) ((C) == '/')
93 # define IS_PATH_WITH_DIR(P) (strchr (P, '/') != NULL)
94 # define FILE_SYSTEM_PREFIX_LEN(P) 0
97 /* Use the system functions, not the gnulib overrides in this file. */
100 #undef set_program_name
103 #if ENABLE_RELOCATABLE
105 #if defined __linux__ || defined __CYGWIN__
106 /* File descriptor of the executable.
107 (Only used to verify that we find the correct executable.) */
108 static int executable_fd
= -1;
111 /* Tests whether a given pathname may belong to the executable. */
113 maybe_executable (const char *filename
)
115 /* The native Windows API lacks the access() function. */
116 #if !defined WINDOWS_NATIVE
117 if (access (filename
, X_OK
) < 0)
121 #if defined __linux__ || defined __CYGWIN__
122 if (executable_fd
>= 0)
124 /* If we already have an executable_fd, check that filename points to
127 struct stat statfile
;
129 if (fstat (executable_fd
, &statexe
) >= 0)
131 if (stat (filename
, &statfile
) < 0)
133 if (!(statfile
.st_dev
134 && statfile
.st_dev
== statexe
.st_dev
135 && statfile
.st_ino
== statexe
.st_ino
))
144 /* Determine the full pathname of the current executable, freshly allocated.
145 Return NULL if unknown.
146 Guaranteed to work on Linux and native Windows. Likely to work on the
147 other Unixes (maybe except BeOS), under most conditions. */
149 find_executable (const char *argv0
)
151 #if defined WINDOWS_NATIVE
152 /* Native Windows only.
153 On Cygwin, it is better to use the Cygwin provided /proc interface, than
154 to use native Windows API and cygwin_conv_to_posix_path, because it
155 supports longer file names
156 (see <https://cygwin.com/ml/cygwin/2011-01/msg00410.html>). */
157 char location
[MAX_PATH
];
158 int length
= GetModuleFileName (NULL
, location
, sizeof (location
));
161 if (!IS_PATH_WITH_DIR (location
))
162 /* Shouldn't happen. */
164 return xstrdup (location
);
165 #elif defined __EMX__
167 char location
[CCHMAXPATH
];
169 /* See http://cyberkinetica.homeunix.net/os2tk45/cp1/619_L2H_DosGetInfoBlocksSynt.html
170 for specification of DosGetInfoBlocks(). */
171 if (DosGetInfoBlocks (NULL
, &ppib
))
174 /* See http://cyberkinetica.homeunix.net/os2tk45/cp1/1247_L2H_DosQueryModuleNameSy.html
175 for specification of DosQueryModuleName(). */
176 if (DosQueryModuleName (ppib
->pib_hmte
, sizeof (location
), location
))
179 _fnslashify (location
);
181 return xstrdup (location
);
184 /* The executable is accessible as /proc/<pid>/exe. In newer Linux
185 versions, also as /proc/self/exe. Linux >= 2.1 provides a symlink
186 to the true pathname; older Linux versions give only device and ino,
187 enclosed in brackets, which we cannot use here. */
191 link
= xreadlink ("/proc/self/exe");
192 if (link
!= NULL
&& link
[0] != '[')
194 if (executable_fd
< 0)
195 executable_fd
= open ("/proc/self/exe", O_EXEC
, 0);
199 sprintf (buf
, "/proc/%d/exe", getpid ());
200 link
= xreadlink (buf
);
201 if (link
!= NULL
&& link
[0] != '[')
203 if (executable_fd
< 0)
204 executable_fd
= open (buf
, O_EXEC
, 0);
209 /* The executable is accessible as /proc/<pid>/exe, at least in
214 link
= xreadlink ("/proc/self/exe");
217 if (executable_fd
< 0)
218 executable_fd
= open ("/proc/self/exe", O_EXEC
, 0);
221 # if HAVE_MACH_O_DYLD_H && HAVE__NSGETEXECUTABLEPATH
222 /* On Mac OS X 10.2 or newer, the function
223 int _NSGetExecutablePath (char *buf, uint32_t *bufsize);
224 can be used to retrieve the executable's full path. */
226 unsigned int length
= sizeof (location
);
227 if (_NSGetExecutablePath (location
, &length
) == 0
228 && location
[0] == '/')
229 return canonicalize_file_name (location
);
231 /* Guess the executable's full path. We assume the executable has been
232 called via execlp() or execvp() with properly set up argv[0]. The
233 login(1) convention to add a '-' prefix to argv[0] is not supported. */
235 bool has_slash
= false;
238 for (p
= argv0
; *p
; p
++)
247 /* exec searches paths without slashes in the directory list given
249 const char *path
= getenv ("PATH");
256 for (p
= path
; *p
; p
= p_next
)
266 p_next
= (*q
== '\0' ? q
: q
+ 1);
268 /* We have a path item at p, of length p_len.
269 Now concatenate the path item and argv0. */
270 concat_name
= (char *) xmalloc (p_len
+ strlen (argv0
) + 2);
272 if (concat_name
== NULL
)
276 /* An empty PATH element designates the current directory. */
277 strcpy (concat_name
, argv0
);
280 memcpy (concat_name
, p
, p_len
);
281 concat_name
[p_len
] = '/';
282 strcpy (concat_name
+ p_len
+ 1, argv0
);
284 if (maybe_executable (concat_name
))
285 return canonicalize_file_name (concat_name
);
289 /* Not found in the PATH, assume the current directory. */
291 /* exec treats paths containing slashes as relative to the current
293 if (maybe_executable (argv0
))
294 return canonicalize_file_name (argv0
);
296 /* No way to find the executable. */
301 /* Full pathname of executable, or NULL. */
302 static char *executable_fullname
;
305 prepare_relocate (const char *orig_installprefix
, const char *orig_installdir
,
310 /* Determine the full pathname of the current executable. */
311 executable_fullname
= find_executable (argv0
);
313 /* Determine the current installation prefix from it. */
314 curr_prefix
= compute_curr_prefix (orig_installprefix
, orig_installdir
,
315 executable_fullname
);
316 if (curr_prefix
!= NULL
)
318 /* Now pass this prefix to all copies of the relocate.c source file. */
319 set_relocation_prefix (orig_installprefix
, curr_prefix
);
325 /* Set program_name, based on argv[0], and original installation prefix and
326 directory, for relocatability. */
328 set_program_name_and_installdir (const char *argv0
,
329 const char *orig_installprefix
,
330 const char *orig_installdir
)
332 const char *argv0_stripped
= argv0
;
334 /* Relocatable programs are renamed to .bin by install-reloc. Or, more
335 generally, their suffix is changed from $exeext to .bin$exeext.
336 Remove the ".bin" here. */
338 size_t argv0_len
= strlen (argv0
);
339 const size_t exeext_len
= sizeof (EXEEXT
) - sizeof ("");
340 if (argv0_len
> 4 + exeext_len
)
341 if (memcmp (argv0
+ argv0_len
- exeext_len
- 4, ".bin", 4) == 0)
343 if (sizeof (EXEEXT
) > sizeof (""))
345 /* Compare using an inlined copy of c_strncasecmp(), because
346 the filenames may have undergone a case conversion since
347 they were packaged. In other words, EXEEXT may be ".exe"
348 on one system and ".EXE" on another. */
349 static const char exeext
[] = EXEEXT
;
350 const char *s1
= argv0
+ argv0_len
- exeext_len
;
351 const char *s2
= exeext
;
352 for (; *s1
!= '\0'; s1
++, s2
++)
354 unsigned char c1
= *s1
;
355 unsigned char c2
= *s2
;
356 if ((c1
>= 'A' && c1
<= 'Z' ? c1
- 'A' + 'a' : c1
)
357 != (c2
>= 'A' && c2
<= 'Z' ? c2
- 'A' + 'a' : c2
))
361 /* Remove ".bin" before EXEEXT or its equivalent. */
363 char *shorter
= (char *) xmalloc (argv0_len
- 4 + 1);
368 memcpy (shorter
, argv0
, argv0_len
- exeext_len
- 4);
369 if (sizeof (EXEEXT
) > sizeof (""))
370 memcpy (shorter
+ argv0_len
- exeext_len
- 4,
371 argv0
+ argv0_len
- exeext_len
- 4,
373 shorter
[argv0_len
- 4] = '\0';
374 argv0_stripped
= shorter
;
381 set_program_name (argv0_stripped
);
383 prepare_relocate (orig_installprefix
, orig_installdir
, argv0
);
386 /* Return the full pathname of the current executable, based on the earlier
387 call to set_program_name_and_installdir. Return NULL if unknown. */
389 get_full_program_name (void)
391 return executable_fullname
;