blob: e9d969bd1f261c52a73373a757bad52cf97a09c7 [file] [log] [blame]
Guido van Rossum582646a1996-05-28 22:30:17 +00001/* Return the initial module search path. */
2
Guido van Rossum667d7041995-08-04 04:20:48 +00003#include "Python.h"
4#include "osdefs.h"
5
Guido van Rossum305e5d01997-04-11 17:18:45 +00006#include <sys/types.h>
Guido van Rossum21f84971997-06-02 22:18:31 +00007#include <string.h>
Guido van Rossum667d7041995-08-04 04:20:48 +00008
Brett Cannonf6af76d2004-06-26 04:03:06 +00009#ifdef __APPLE__
Guido van Rossum54ecc3d1999-01-27 17:53:11 +000010#include <mach-o/dyld.h>
11#endif
12
Guido van Rossum305e5d01997-04-11 17:18:45 +000013/* Search in some common locations for the associated Python libraries.
14 *
15 * Two directories must be found, the platform independent directory
Barry Warsaw90126031997-04-11 20:27:03 +000016 * (prefix), containing the common .py and .pyc files, and the platform
17 * dependent directory (exec_prefix), containing the shared library
18 * modules. Note that prefix and exec_prefix can be the same directory,
19 * but for some installations, they are different.
Guido van Rossum305e5d01997-04-11 17:18:45 +000020 *
Barry Warsaw90126031997-04-11 20:27:03 +000021 * Py_GetPath() carries out separate searches for prefix and exec_prefix.
22 * Each search tries a number of different locations until a ``landmark''
23 * file or directory is found. If no prefix or exec_prefix is found, a
24 * warning message is issued and the preprocessor defined PREFIX and
25 * EXEC_PREFIX are used (even though they will not work); python carries on
26 * as best as is possible, but most imports will fail.
Guido van Rossum305e5d01997-04-11 17:18:45 +000027 *
28 * Before any searches are done, the location of the executable is
Georg Brandl74780962007-03-10 07:38:14 +000029 * determined. If argv[0] has one or more slashes in it, it is used
Barry Warsaw90126031997-04-11 20:27:03 +000030 * unchanged. Otherwise, it must have been invoked from the shell's path,
31 * so we search $PATH for the named executable and use that. If the
32 * executable was not found on $PATH (or there was no $PATH environment
33 * variable), the original argv[0] string is used.
Guido van Rossum305e5d01997-04-11 17:18:45 +000034 *
Barry Warsaw90126031997-04-11 20:27:03 +000035 * Next, the executable location is examined to see if it is a symbolic
36 * link. If so, the link is chased (correctly interpreting a relative
37 * pathname if one is found) and the directory of the link target is used.
Guido van Rossum305e5d01997-04-11 17:18:45 +000038 *
Barry Warsaw90126031997-04-11 20:27:03 +000039 * Finally, argv0_path is set to the directory containing the executable
40 * (i.e. the last component is stripped).
Guido van Rossum305e5d01997-04-11 17:18:45 +000041 *
Barry Warsaw90126031997-04-11 20:27:03 +000042 * With argv0_path in hand, we perform a number of steps. The same steps
43 * are performed for prefix and for exec_prefix, but with a different
44 * landmark.
Guido van Rossum305e5d01997-04-11 17:18:45 +000045 *
46 * Step 1. Are we running python out of the build directory? This is
47 * checked by looking for a different kind of landmark relative to
Barry Warsaw90126031997-04-11 20:27:03 +000048 * argv0_path. For prefix, the landmark's path is derived from the VPATH
49 * preprocessor variable (taking into account that its value is almost, but
50 * not quite, what we need). For exec_prefix, the landmark is
51 * Modules/Setup. If the landmark is found, we're done.
Guido van Rossum305e5d01997-04-11 17:18:45 +000052 *
53 * For the remaining steps, the prefix landmark will always be
Jeremy Hylton847a9962000-05-26 21:49:07 +000054 * lib/python$VERSION/os.py and the exec_prefix will always be
Guido van Rossum266033e1997-10-20 23:20:32 +000055 * lib/python$VERSION/lib-dynload, where $VERSION is Python's version
Barry Warsaw90126031997-04-11 20:27:03 +000056 * number as supplied by the Makefile. Note that this means that no more
57 * build directory checking is performed; if the first step did not find
58 * the landmarks, the assumption is that python is running from an
59 * installed setup.
Guido van Rossum305e5d01997-04-11 17:18:45 +000060 *
61 * Step 2. See if the $PYTHONHOME environment variable points to the
Barry Warsaw90126031997-04-11 20:27:03 +000062 * installed location of the Python libraries. If $PYTHONHOME is set, then
63 * it points to prefix and exec_prefix. $PYTHONHOME can be a single
64 * directory, which is used for both, or the prefix and exec_prefix
65 * directories separated by a colon.
Guido van Rossum305e5d01997-04-11 17:18:45 +000066 *
67 * Step 3. Try to find prefix and exec_prefix relative to argv0_path,
Barry Warsaw90126031997-04-11 20:27:03 +000068 * backtracking up the path until it is exhausted. This is the most common
69 * step to succeed. Note that if prefix and exec_prefix are different,
70 * exec_prefix is more likely to be found; however if exec_prefix is a
71 * subdirectory of prefix, both will be found.
Guido van Rossum305e5d01997-04-11 17:18:45 +000072 *
Barry Warsaw90126031997-04-11 20:27:03 +000073 * Step 4. Search the directories pointed to by the preprocessor variables
74 * PREFIX and EXEC_PREFIX. These are supplied by the Makefile but can be
75 * passed in as options to the configure script.
Guido van Rossum305e5d01997-04-11 17:18:45 +000076 *
Barry Warsaw90126031997-04-11 20:27:03 +000077 * That's it!
78 *
79 * Well, almost. Once we have determined prefix and exec_prefix, the
Thomas Wouters7e474022000-07-16 12:04:32 +000080 * preprocessor variable PYTHONPATH is used to construct a path. Each
Barry Warsaw90126031997-04-11 20:27:03 +000081 * relative path on PYTHONPATH is prefixed with prefix. Then the directory
82 * containing the shared library modules is appended. The environment
83 * variable $PYTHONPATH is inserted in front of it all. Finally, the
84 * prefix and exec_prefix globals are tweaked so they reflect the values
85 * expected by other code, by stripping the "lib/python$VERSION/..." stuff
86 * off. If either points to the build directory, the globals are reset to
87 * the corresponding preprocessor variables (so sys.prefix will reflect the
88 * installation location, even though sys.path points into the build
89 * directory). This seems to make more sense given that currently the only
90 * known use of sys.prefix and sys.exec_prefix is for the ILU installation
91 * process to find the installed Python tree.
92 */
Guido van Rossum305e5d01997-04-11 17:18:45 +000093
Anthony Baxterac6bd462006-04-13 02:06:09 +000094#ifdef __cplusplus
95 extern "C" {
96#endif
97
98
Benjamin Petersone7257772016-06-02 12:41:35 -070099#if !defined(PREFIX) || !defined(EXEC_PREFIX) || !defined(VERSION) || !defined(VPATH)
100#error "PREFIX, EXEC_PREFIX, VERSION, and VPATH must be constant defined"
Guido van Rossum305e5d01997-04-11 17:18:45 +0000101#endif
Guido van Rossum667d7041995-08-04 04:20:48 +0000102
Guido van Rossum305e5d01997-04-11 17:18:45 +0000103#ifndef LANDMARK
Jeremy Hylton847a9962000-05-26 21:49:07 +0000104#define LANDMARK "os.py"
Guido van Rossum305e5d01997-04-11 17:18:45 +0000105#endif
Guido van Rossume296ced2001-09-28 20:00:29 +0000106
Nan Zhangced27512017-06-19 18:01:34 -0700107#ifndef INTERNALDIR
108#define INTERNALDIR "internal"
109#endif
110
111#ifndef STDLIBDIR
112#define STDLIBDIR "stdlib"
113#endif
114
Guido van Rossum305e5d01997-04-11 17:18:45 +0000115static char prefix[MAXPATHLEN+1];
116static char exec_prefix[MAXPATHLEN+1];
Guido van Rossum7929c6f1997-05-20 22:38:21 +0000117static char progpath[MAXPATHLEN+1];
Guido van Rossum305e5d01997-04-11 17:18:45 +0000118static char *module_search_path = NULL;
Fred Drakeb64c2232000-09-28 14:32:29 +0000119static char lib_python[] = "lib/python" VERSION;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000120
121static void
Fred Drakeedabdc12000-07-08 06:16:37 +0000122reduce(char *dir)
Guido van Rossum305e5d01997-04-11 17:18:45 +0000123{
Fred Drakeedabdc12000-07-08 06:16:37 +0000124 size_t i = strlen(dir);
125 while (i > 0 && dir[i] != SEP)
126 --i;
127 dir[i] = '\0';
Guido van Rossum305e5d01997-04-11 17:18:45 +0000128}
Guido van Rossumd29806c1998-01-19 22:06:22 +0000129
130
Guido van Rossum305e5d01997-04-11 17:18:45 +0000131static int
Guido van Rossume296ced2001-09-28 20:00:29 +0000132isfile(char *filename) /* Is file, not directory */
Guido van Rossum305e5d01997-04-11 17:18:45 +0000133{
Fred Drakeedabdc12000-07-08 06:16:37 +0000134 struct stat buf;
135 if (stat(filename, &buf) != 0)
136 return 0;
137 if (!S_ISREG(buf.st_mode))
138 return 0;
139 return 1;
Guido van Rossumd29806c1998-01-19 22:06:22 +0000140}
141
142
143static int
Guido van Rossume296ced2001-09-28 20:00:29 +0000144ismodule(char *filename) /* Is module -- check for .pyc/.pyo too */
Guido van Rossumd29806c1998-01-19 22:06:22 +0000145{
Fred Drakeedabdc12000-07-08 06:16:37 +0000146 if (isfile(filename))
147 return 1;
Guido van Rossumd29806c1998-01-19 22:06:22 +0000148
Fred Drakeedabdc12000-07-08 06:16:37 +0000149 /* Check for the compiled version of prefix. */
150 if (strlen(filename) < MAXPATHLEN) {
151 strcat(filename, Py_OptimizeFlag ? "o" : "c");
152 if (isfile(filename))
153 return 1;
154 }
155 return 0;
Guido van Rossumd29806c1998-01-19 22:06:22 +0000156}
157
158
159static int
Guido van Rossume296ced2001-09-28 20:00:29 +0000160isxfile(char *filename) /* Is executable file */
Guido van Rossumd29806c1998-01-19 22:06:22 +0000161{
Fred Drakeedabdc12000-07-08 06:16:37 +0000162 struct stat buf;
163 if (stat(filename, &buf) != 0)
164 return 0;
165 if (!S_ISREG(buf.st_mode))
166 return 0;
167 if ((buf.st_mode & 0111) == 0)
168 return 0;
169 return 1;
Guido van Rossumd29806c1998-01-19 22:06:22 +0000170}
171
172
173static int
Guido van Rossume296ced2001-09-28 20:00:29 +0000174isdir(char *filename) /* Is directory */
Guido van Rossumd29806c1998-01-19 22:06:22 +0000175{
Fred Drakeedabdc12000-07-08 06:16:37 +0000176 struct stat buf;
177 if (stat(filename, &buf) != 0)
178 return 0;
179 if (!S_ISDIR(buf.st_mode))
180 return 0;
181 return 1;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000182}
183
184
Tim Petersec8c5a92004-08-08 01:00:47 +0000185/* Add a path component, by appending stuff to buffer.
186 buffer must have at least MAXPATHLEN + 1 bytes allocated, and contain a
187 NUL-terminated string with no more than MAXPATHLEN characters (not counting
188 the trailing NUL). It's a fatal error if it contains a string longer than
189 that (callers must be careful!). If these requirements are met, it's
190 guaranteed that buffer will still be a NUL-terminated string with no more
191 than MAXPATHLEN characters at exit. If stuff is too long, only as much of
192 stuff as fits will be appended.
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000193*/
Guido van Rossum305e5d01997-04-11 17:18:45 +0000194static void
Fred Drakeedabdc12000-07-08 06:16:37 +0000195joinpath(char *buffer, char *stuff)
Guido van Rossum305e5d01997-04-11 17:18:45 +0000196{
Fred Drakeedabdc12000-07-08 06:16:37 +0000197 size_t n, k;
198 if (stuff[0] == SEP)
199 n = 0;
200 else {
201 n = strlen(buffer);
202 if (n > 0 && buffer[n-1] != SEP && n < MAXPATHLEN)
203 buffer[n++] = SEP;
204 }
Tim Petersec8c5a92004-08-08 01:00:47 +0000205 if (n > MAXPATHLEN)
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000206 Py_FatalError("buffer overflow in getpath.c's joinpath()");
Fred Drakeedabdc12000-07-08 06:16:37 +0000207 k = strlen(stuff);
208 if (n + k > MAXPATHLEN)
209 k = MAXPATHLEN - n;
210 strncpy(buffer+n, stuff, k);
211 buffer[n+k] = '\0';
Guido van Rossum305e5d01997-04-11 17:18:45 +0000212}
213
Guido van Rossume296ced2001-09-28 20:00:29 +0000214/* copy_absolute requires that path be allocated at least
215 MAXPATHLEN + 1 bytes and that p be no more than MAXPATHLEN bytes. */
Jeremy Hylton7198ba92000-09-25 17:00:24 +0000216static void
Guido van Rossume296ced2001-09-28 20:00:29 +0000217copy_absolute(char *path, char *p)
Jeremy Hylton7198ba92000-09-25 17:00:24 +0000218{
Guido van Rossume296ced2001-09-28 20:00:29 +0000219 if (p[0] == SEP)
220 strcpy(path, p);
Jeremy Hylton7198ba92000-09-25 17:00:24 +0000221 else {
Victor Stinner354fe7e2010-10-07 23:37:08 +0000222 if (!getcwd(path, MAXPATHLEN)) {
223 /* unable to get the current directory */
224 strcpy(path, p);
225 return;
226 }
Guido van Rossume296ced2001-09-28 20:00:29 +0000227 if (p[0] == '.' && p[1] == SEP)
228 p += 2;
229 joinpath(path, p);
Jeremy Hylton7198ba92000-09-25 17:00:24 +0000230 }
231}
Guido van Rossum305e5d01997-04-11 17:18:45 +0000232
Guido van Rossume296ced2001-09-28 20:00:29 +0000233/* absolutize() requires that path be allocated at least MAXPATHLEN+1 bytes. */
234static void
235absolutize(char *path)
236{
237 char buffer[MAXPATHLEN + 1];
238
239 if (path[0] == SEP)
240 return;
241 copy_absolute(buffer, path);
242 strcpy(path, buffer);
243}
244
245/* search_for_prefix requires that argv0_path be no more than MAXPATHLEN
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000246 bytes long.
247*/
Guido van Rossum305e5d01997-04-11 17:18:45 +0000248static int
Fred Drakeedabdc12000-07-08 06:16:37 +0000249search_for_prefix(char *argv0_path, char *home)
Guido van Rossum305e5d01997-04-11 17:18:45 +0000250{
Fred Drakeedabdc12000-07-08 06:16:37 +0000251 size_t n;
252 char *vpath;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000253
Fred Drakeedabdc12000-07-08 06:16:37 +0000254 /* If PYTHONHOME is set, we believe it unconditionally */
255 if (home) {
256 char *delim;
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000257 strncpy(prefix, home, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000258 delim = strchr(prefix, DELIM);
259 if (delim)
260 *delim = '\0';
261 joinpath(prefix, lib_python);
262 joinpath(prefix, LANDMARK);
263 return 1;
264 }
Jeremy Hylton847a9962000-05-26 21:49:07 +0000265
Nan Zhangced27512017-06-19 18:01:34 -0700266 // GOOGLE(nanzhang): Always set prefix with hermetic executable full path.
Fred Drakeedabdc12000-07-08 06:16:37 +0000267 strcpy(prefix, argv0_path);
Nan Zhangced27512017-06-19 18:01:34 -0700268 return 1;
269
270 /* Check to see if argv[0] is in the build directory */
Fred Drakeedabdc12000-07-08 06:16:37 +0000271 joinpath(prefix, "Modules/Setup");
272 if (isfile(prefix)) {
Neil Schemenauer6cf07022001-01-24 17:13:11 +0000273 /* Check VPATH to see if argv0_path is in the build directory. */
Fred Drakeedabdc12000-07-08 06:16:37 +0000274 vpath = VPATH;
Fred Drakeedabdc12000-07-08 06:16:37 +0000275 strcpy(prefix, argv0_path);
276 joinpath(prefix, vpath);
Fred Drakeedabdc12000-07-08 06:16:37 +0000277 joinpath(prefix, "Lib");
278 joinpath(prefix, LANDMARK);
279 if (ismodule(prefix))
280 return -1;
281 }
Guido van Rossum305e5d01997-04-11 17:18:45 +0000282
Fred Drakeedabdc12000-07-08 06:16:37 +0000283 /* Search from argv0_path, until root is found */
Guido van Rossume296ced2001-09-28 20:00:29 +0000284 copy_absolute(prefix, argv0_path);
Fred Drakeedabdc12000-07-08 06:16:37 +0000285 do {
286 n = strlen(prefix);
287 joinpath(prefix, lib_python);
288 joinpath(prefix, LANDMARK);
289 if (ismodule(prefix))
290 return 1;
291 prefix[n] = '\0';
292 reduce(prefix);
293 } while (prefix[0]);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000294
Fred Drakeedabdc12000-07-08 06:16:37 +0000295 /* Look at configure's PREFIX */
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000296 strncpy(prefix, PREFIX, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000297 joinpath(prefix, lib_python);
298 joinpath(prefix, LANDMARK);
299 if (ismodule(prefix))
300 return 1;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000301
Fred Drakeedabdc12000-07-08 06:16:37 +0000302 /* Fail */
303 return 0;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000304}
305
306
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000307/* search_for_exec_prefix requires that argv0_path be no more than
Guido van Rossume296ced2001-09-28 20:00:29 +0000308 MAXPATHLEN bytes long.
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000309*/
Guido van Rossum305e5d01997-04-11 17:18:45 +0000310static int
Fred Drakeedabdc12000-07-08 06:16:37 +0000311search_for_exec_prefix(char *argv0_path, char *home)
Guido van Rossum305e5d01997-04-11 17:18:45 +0000312{
Fred Drakeedabdc12000-07-08 06:16:37 +0000313 size_t n;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000314
Fred Drakeedabdc12000-07-08 06:16:37 +0000315 /* If PYTHONHOME is set, we believe it unconditionally */
316 if (home) {
317 char *delim;
318 delim = strchr(home, DELIM);
319 if (delim)
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000320 strncpy(exec_prefix, delim+1, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000321 else
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000322 strncpy(exec_prefix, home, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000323 joinpath(exec_prefix, lib_python);
324 joinpath(exec_prefix, "lib-dynload");
325 return 1;
326 }
Guido van Rossum305e5d01997-04-11 17:18:45 +0000327
Nan Zhangced27512017-06-19 18:01:34 -0700328 // GOOGLE(nanzhang): Always set exec_prefix with hermetic executable full path.
329 strcpy(exec_prefix, argv0_path);
330 return 1;
331
doko@ubuntu.com6cb43432013-04-08 21:20:09 +0200332 /* Check to see if argv[0] is in the build directory. "pybuilddir.txt"
333 is written by setup.py and contains the relative path to the location
334 of shared library modules. */
doko@ubuntu.com6cb43432013-04-08 21:20:09 +0200335 joinpath(exec_prefix, "pybuilddir.txt");
Fred Drakeedabdc12000-07-08 06:16:37 +0000336 if (isfile(exec_prefix)) {
doko@ubuntu.com6cb43432013-04-08 21:20:09 +0200337 FILE *f = fopen(exec_prefix, "r");
338 if (f == NULL)
339 errno = 0;
340 else {
341 char rel_builddir_path[MAXPATHLEN+1];
342 size_t n;
343 n = fread(rel_builddir_path, 1, MAXPATHLEN, f);
344 rel_builddir_path[n] = '\0';
345 fclose(f);
Serhiy Storchaka6a35bf62016-10-08 09:58:08 +0300346 strcpy(exec_prefix, argv0_path);
347 joinpath(exec_prefix, rel_builddir_path);
348 return -1;
doko@ubuntu.com6cb43432013-04-08 21:20:09 +0200349 }
Fred Drakeedabdc12000-07-08 06:16:37 +0000350 }
Jeremy Hylton847a9962000-05-26 21:49:07 +0000351
Fred Drakeedabdc12000-07-08 06:16:37 +0000352 /* Search from argv0_path, until root is found */
Guido van Rossume296ced2001-09-28 20:00:29 +0000353 copy_absolute(exec_prefix, argv0_path);
Fred Drakeedabdc12000-07-08 06:16:37 +0000354 do {
355 n = strlen(exec_prefix);
356 joinpath(exec_prefix, lib_python);
357 joinpath(exec_prefix, "lib-dynload");
358 if (isdir(exec_prefix))
359 return 1;
360 exec_prefix[n] = '\0';
361 reduce(exec_prefix);
362 } while (exec_prefix[0]);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000363
Fred Drakeedabdc12000-07-08 06:16:37 +0000364 /* Look at configure's EXEC_PREFIX */
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000365 strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000366 joinpath(exec_prefix, lib_python);
367 joinpath(exec_prefix, "lib-dynload");
368 if (isdir(exec_prefix))
369 return 1;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000370
Fred Drakeedabdc12000-07-08 06:16:37 +0000371 /* Fail */
372 return 0;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000373}
374
375
376static void
Thomas Woutersf3f33dc2000-07-21 06:00:07 +0000377calculate_path(void)
Guido van Rossum305e5d01997-04-11 17:18:45 +0000378{
Thomas Woutersbd4bc4e2000-07-22 23:57:55 +0000379 extern char *Py_GetProgramName(void);
Fred Drakeedabdc12000-07-08 06:16:37 +0000380 static char delimiter[2] = {DELIM, '\0'};
381 static char separator[2] = {SEP, '\0'};
382 char *pythonpath = PYTHONPATH;
Fred Drakeedabdc12000-07-08 06:16:37 +0000383 char *home = Py_GetPythonHome();
Nan Zhangced27512017-06-19 18:01:34 -0700384 // We have overrided argv[0] using the full path to the hermetic Python
385 // launcher itself. And then Py_SetProgramName(argv[0]) was invoked at
386 // launcher_main.cpp. The launcher_main.cpp has guaranteed that
387 // strlen(Py_GetProgramName()) must not exceed MAXPATHLEN.
Fred Drakeedabdc12000-07-08 06:16:37 +0000388 char *prog = Py_GetProgramName();
389 char argv0_path[MAXPATHLEN+1];
Fred Drakeedabdc12000-07-08 06:16:37 +0000390 char *buf;
391 size_t bufsz;
Nan Zhangced27512017-06-19 18:01:34 -0700392
393 strncpy(progpath, prog, MAXPATHLEN);
394 progpath[MAXPATHLEN] = '\0' /* In case of no NUL-termination. */;
395 strncpy(argv0_path, prog, MAXPATHLEN);
396 argv0_path[MAXPATHLEN] = '\0' /* In case of no NUL-termination. */;
397
398 // We don't reduce the path of prefix, and exec_prefix.
399 search_for_prefix(argv0_path, home);
400 search_for_exec_prefix(argv0_path, home);
401
402 // Calculate size of return buffer.
403 bufsz = strlen(prog) + 1 + sizeof(INTERNALDIR) /* 1 is for SEP */;
404 bufsz += strlen(prog) + 1 + sizeof(INTERNALDIR) + 1 + sizeof(STDLIBDIR) /* 1 is for SEP */;
405
406 /* This is the only malloc call in this file */
407 buf = (char *)PyMem_Malloc(bufsz);
408
409 if (buf == NULL) {
410 /* We can't exit, so print a warning and limp along */
411 fprintf(stderr, "Not enough memory for dynamic PYTHONPATH.\n");
412 fprintf(stderr, "Using default static PYTHONPATH.\n");
413 exit(1);
414 } else {
415 buf[0] = '\0';
416 strcat(buf, prefix);
417 strcat(buf, separator);
418 strcat(buf, INTERNALDIR);
419 strcat(buf, delimiter);
420
421 strcat(buf, prefix);
422 strcat(buf, separator);
423 strcat(buf, INTERNALDIR);
424 strcat(buf, separator);
425 strcat(buf, STDLIBDIR);
426
427 module_search_path = buf;
428 }
429 // GOOGLE(nanzhang): Don't need all the code below for embedded Python launcher.
430 return;
431
432 char *path = getenv("PATH");
433 char *rtpypath = Py_GETENV("PYTHONPATH");
434 char zip_path[MAXPATHLEN+1];
435 int pfound, efound; /* 1 if found; -1 if found build directory */
Fred Drakeedabdc12000-07-08 06:16:37 +0000436 size_t prefixsz;
437 char *defpath = pythonpath;
Guido van Rossum54ecc3d1999-01-27 17:53:11 +0000438#ifdef WITH_NEXT_FRAMEWORK
Fred Drakeedabdc12000-07-08 06:16:37 +0000439 NSModule pythonModule;
Guido van Rossum54ecc3d1999-01-27 17:53:11 +0000440#endif
Jack Jansen1afd4802004-06-03 14:33:03 +0000441#ifdef __APPLE__
Skip Montanaro2b474452006-01-05 10:49:13 +0000442#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
Brett Cannonbd9c3f72005-09-16 02:43:35 +0000443 uint32_t nsexeclength = MAXPATHLEN;
Skip Montanaro2b474452006-01-05 10:49:13 +0000444#else
445 unsigned long nsexeclength = MAXPATHLEN;
446#endif
Jack Jansen1afd4802004-06-03 14:33:03 +0000447#endif
Guido van Rossume296ced2001-09-28 20:00:29 +0000448
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000449 /* If there is no slash in the argv0 path, then we have to
450 * assume python is on the user's $PATH, since there's no
451 * other way to find a directory to start the search from. If
452 * $PATH isn't exported, you lose.
453 */
454 if (strchr(prog, SEP))
455 strncpy(progpath, prog, MAXPATHLEN);
Jack Jansen1afd4802004-06-03 14:33:03 +0000456#ifdef __APPLE__
457 /* On Mac OS X, if a script uses an interpreter of the form
458 * "#!/opt/python2.3/bin/python", the kernel only passes "python"
459 * as argv[0], which falls through to the $PATH search below.
460 * If /opt/python2.3/bin isn't in your path, or is near the end,
461 * this algorithm may incorrectly find /usr/bin/python. To work
462 * around this, we can use _NSGetExecutablePath to get a better
463 * hint of what the intended interpreter was, although this
464 * will fail if a relative path was used. but in that case,
465 * absolutize() should help us out below
466 */
467 else if(0 == _NSGetExecutablePath(progpath, &nsexeclength) && progpath[0] == SEP)
468 ;
Brett Cannon6cc48142004-06-24 00:48:44 +0000469#endif /* __APPLE__ */
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000470 else if (path) {
471 while (1) {
472 char *delim = strchr(path, DELIM);
Jack Jansen55070f52001-12-02 23:56:28 +0000473
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000474 if (delim) {
475 size_t len = delim - path;
476 if (len > MAXPATHLEN)
477 len = MAXPATHLEN;
478 strncpy(progpath, path, len);
479 *(progpath + len) = '\0';
480 }
481 else
482 strncpy(progpath, path, MAXPATHLEN);
Jack Jansen55070f52001-12-02 23:56:28 +0000483
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000484 joinpath(progpath, prog);
485 if (isxfile(progpath))
486 break;
Jack Jansen55070f52001-12-02 23:56:28 +0000487
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000488 if (!delim) {
489 progpath[0] = '\0';
490 break;
491 }
492 path = delim + 1;
493 }
494 }
495 else
496 progpath[0] = '\0';
497 if (progpath[0] != SEP && progpath[0] != '\0')
498 absolutize(progpath);
499 strncpy(argv0_path, progpath, MAXPATHLEN);
500 argv0_path[MAXPATHLEN] = '\0';
Jack Jansen55070f52001-12-02 23:56:28 +0000501
Guido van Rossum54ecc3d1999-01-27 17:53:11 +0000502#ifdef WITH_NEXT_FRAMEWORK
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000503 /* On Mac OS X we have a special case if we're running from a framework.
504 ** This is because the python home should be set relative to the library,
505 ** which is in the framework, not relative to the executable, which may
506 ** be outside of the framework. Except when we're in the build directory...
507 */
Fred Drakeedabdc12000-07-08 06:16:37 +0000508 pythonModule = NSModuleForSymbol(NSLookupAndBindSymbol("_Py_Initialize"));
509 /* Use dylib functions to find out where the framework was loaded from */
Jack Jansen0a116f32002-12-23 21:03:36 +0000510 buf = (char *)NSLibraryNameForModule(pythonModule);
Fred Drakeedabdc12000-07-08 06:16:37 +0000511 if (buf != NULL) {
512 /* We're in a framework. */
Jack Jansene925faf2001-08-15 01:14:40 +0000513 /* See if we might be in the build directory. The framework in the
514 ** build directory is incomplete, it only has the .dylib and a few
515 ** needed symlinks, it doesn't have the Lib directories and such.
516 ** If we're running with the framework from the build directory we must
517 ** be running the interpreter in the build directory, so we use the
518 ** build-directory-specific logic to find Lib and such.
519 */
520 strncpy(argv0_path, buf, MAXPATHLEN);
521 reduce(argv0_path);
522 joinpath(argv0_path, lib_python);
523 joinpath(argv0_path, LANDMARK);
524 if (!ismodule(argv0_path)) {
Guido van Rossume296ced2001-09-28 20:00:29 +0000525 /* We are in the build directory so use the name of the
526 executable - we know that the absolute path is passed */
Ronald Oussorenc22b7182010-07-23 16:12:28 +0000527 strncpy(argv0_path, progpath, MAXPATHLEN);
Jack Jansene925faf2001-08-15 01:14:40 +0000528 }
529 else {
Guido van Rossume296ced2001-09-28 20:00:29 +0000530 /* Use the location of the library as the progpath */
Jack Jansen55070f52001-12-02 23:56:28 +0000531 strncpy(argv0_path, buf, MAXPATHLEN);
Jack Jansene925faf2001-08-15 01:14:40 +0000532 }
Fred Drakeedabdc12000-07-08 06:16:37 +0000533 }
Guido van Rossum54ecc3d1999-01-27 17:53:11 +0000534#endif
Guido van Rossume296ced2001-09-28 20:00:29 +0000535
Guido van Rossum305e5d01997-04-11 17:18:45 +0000536#if HAVE_READLINK
Fred Drakeedabdc12000-07-08 06:16:37 +0000537 {
538 char tmpbuffer[MAXPATHLEN+1];
539 int linklen = readlink(progpath, tmpbuffer, MAXPATHLEN);
540 while (linklen != -1) {
541 /* It's not null terminated! */
542 tmpbuffer[linklen] = '\0';
543 if (tmpbuffer[0] == SEP)
Guido van Rossume296ced2001-09-28 20:00:29 +0000544 /* tmpbuffer should never be longer than MAXPATHLEN,
545 but extra check does not hurt */
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000546 strncpy(argv0_path, tmpbuffer, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000547 else {
548 /* Interpret relative to progpath */
549 reduce(argv0_path);
550 joinpath(argv0_path, tmpbuffer);
551 }
552 linklen = readlink(argv0_path, tmpbuffer, MAXPATHLEN);
553 }
554 }
Guido van Rossum305e5d01997-04-11 17:18:45 +0000555#endif /* HAVE_READLINK */
556
Fred Drakeedabdc12000-07-08 06:16:37 +0000557 reduce(argv0_path);
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000558 /* At this point, argv0_path is guaranteed to be less than
559 MAXPATHLEN bytes long.
560 */
Guido van Rossum305e5d01997-04-11 17:18:45 +0000561
Fred Drakeedabdc12000-07-08 06:16:37 +0000562 if (!(pfound = search_for_prefix(argv0_path, home))) {
563 if (!Py_FrozenFlag)
564 fprintf(stderr,
Guido van Rossume296ced2001-09-28 20:00:29 +0000565 "Could not find platform independent libraries <prefix>\n");
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000566 strncpy(prefix, PREFIX, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000567 joinpath(prefix, lib_python);
568 }
569 else
570 reduce(prefix);
Guido van Rossume296ced2001-09-28 20:00:29 +0000571
Just van Rossum52e14d62002-12-30 22:08:05 +0000572 strncpy(zip_path, prefix, MAXPATHLEN);
Neal Norwitzb70557f2002-12-31 12:45:12 +0000573 zip_path[MAXPATHLEN] = '\0';
Just van Rossum52e14d62002-12-30 22:08:05 +0000574 if (pfound > 0) { /* Use the reduced prefix returned by Py_GetPrefix() */
575 reduce(zip_path);
576 reduce(zip_path);
577 }
578 else
579 strncpy(zip_path, PREFIX, MAXPATHLEN);
580 joinpath(zip_path, "lib/python00.zip");
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000581 bufsz = strlen(zip_path); /* Replace "00" with version */
Just van Rossum52e14d62002-12-30 22:08:05 +0000582 zip_path[bufsz - 6] = VERSION[0];
583 zip_path[bufsz - 5] = VERSION[2];
584
Fred Drakeedabdc12000-07-08 06:16:37 +0000585 if (!(efound = search_for_exec_prefix(argv0_path, home))) {
586 if (!Py_FrozenFlag)
587 fprintf(stderr,
Guido van Rossume296ced2001-09-28 20:00:29 +0000588 "Could not find platform dependent libraries <exec_prefix>\n");
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000589 strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN);
Fred Drakeedabdc12000-07-08 06:16:37 +0000590 joinpath(exec_prefix, "lib/lib-dynload");
591 }
592 /* If we found EXEC_PREFIX do *not* reduce it! (Yet.) */
Guido van Rossum305e5d01997-04-11 17:18:45 +0000593
Fred Drakeedabdc12000-07-08 06:16:37 +0000594 if ((!pfound || !efound) && !Py_FrozenFlag)
595 fprintf(stderr,
596 "Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]\n");
Guido van Rossum305e5d01997-04-11 17:18:45 +0000597
Fred Drakeedabdc12000-07-08 06:16:37 +0000598 /* Calculate size of return buffer.
599 */
600 bufsz = 0;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000601
Fred Drakeedabdc12000-07-08 06:16:37 +0000602 if (rtpypath)
603 bufsz += strlen(rtpypath) + 1;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000604
Fred Drakeedabdc12000-07-08 06:16:37 +0000605 prefixsz = strlen(prefix) + 1;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000606
Fred Drakeedabdc12000-07-08 06:16:37 +0000607 while (1) {
608 char *delim = strchr(defpath, DELIM);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000609
Fred Drakeedabdc12000-07-08 06:16:37 +0000610 if (defpath[0] != SEP)
611 /* Paths are relative to prefix */
612 bufsz += prefixsz;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000613
Fred Drakeedabdc12000-07-08 06:16:37 +0000614 if (delim)
615 bufsz += delim - defpath + 1;
616 else {
617 bufsz += strlen(defpath) + 1;
618 break;
619 }
620 defpath = delim + 1;
621 }
Guido van Rossum305e5d01997-04-11 17:18:45 +0000622
Just van Rossum52e14d62002-12-30 22:08:05 +0000623 bufsz += strlen(zip_path) + 1;
Fred Drakeedabdc12000-07-08 06:16:37 +0000624 bufsz += strlen(exec_prefix) + 1;
Guido van Rossum305e5d01997-04-11 17:18:45 +0000625
Fred Drakeedabdc12000-07-08 06:16:37 +0000626 /* This is the only malloc call in this file */
Anthony Baxter64182fe2006-04-11 12:14:09 +0000627 buf = (char *)PyMem_Malloc(bufsz);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000628
Fred Drakeedabdc12000-07-08 06:16:37 +0000629 if (buf == NULL) {
630 /* We can't exit, so print a warning and limp along */
631 fprintf(stderr, "Not enough memory for dynamic PYTHONPATH.\n");
632 fprintf(stderr, "Using default static PYTHONPATH.\n");
633 module_search_path = PYTHONPATH;
634 }
635 else {
636 /* Run-time value of $PYTHONPATH goes first */
637 if (rtpypath) {
638 strcpy(buf, rtpypath);
639 strcat(buf, delimiter);
640 }
641 else
642 buf[0] = '\0';
Guido van Rossum305e5d01997-04-11 17:18:45 +0000643
Just van Rossum52e14d62002-12-30 22:08:05 +0000644 /* Next is the default zip path */
645 strcat(buf, zip_path);
646 strcat(buf, delimiter);
647
Fred Drakeedabdc12000-07-08 06:16:37 +0000648 /* Next goes merge of compile-time $PYTHONPATH with
649 * dynamically located prefix.
650 */
651 defpath = pythonpath;
652 while (1) {
653 char *delim = strchr(defpath, DELIM);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000654
Fred Drakeedabdc12000-07-08 06:16:37 +0000655 if (defpath[0] != SEP) {
656 strcat(buf, prefix);
Serhiy Storchaka1e4b73f2016-11-11 12:11:55 +0200657 if (prefixsz >= 2 && prefix[prefixsz - 2] != SEP &&
658 defpath[0] != (delim ? DELIM : L'\0')) { /* not empty */
659 strcat(buf, separator);
660 }
Fred Drakeedabdc12000-07-08 06:16:37 +0000661 }
Guido van Rossum305e5d01997-04-11 17:18:45 +0000662
Fred Drakeedabdc12000-07-08 06:16:37 +0000663 if (delim) {
664 size_t len = delim - defpath + 1;
665 size_t end = strlen(buf) + len;
666 strncat(buf, defpath, len);
667 *(buf + end) = '\0';
668 }
669 else {
670 strcat(buf, defpath);
671 break;
672 }
673 defpath = delim + 1;
674 }
675 strcat(buf, delimiter);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000676
Fred Drakeedabdc12000-07-08 06:16:37 +0000677 /* Finally, on goes the directory for dynamic-load modules */
678 strcat(buf, exec_prefix);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000679
Fred Drakeedabdc12000-07-08 06:16:37 +0000680 /* And publish the results */
681 module_search_path = buf;
682 }
Guido van Rossum305e5d01997-04-11 17:18:45 +0000683
Fred Drakeedabdc12000-07-08 06:16:37 +0000684 /* Reduce prefix and exec_prefix to their essence,
685 * e.g. /usr/local/lib/python1.5 is reduced to /usr/local.
686 * If we're loading relative to the build directory,
687 * return the compiled-in defaults instead.
688 */
689 if (pfound > 0) {
690 reduce(prefix);
691 reduce(prefix);
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000692 /* The prefix is the root directory, but reduce() chopped
693 * off the "/". */
694 if (!prefix[0])
695 strcpy(prefix, separator);
Fred Drakeedabdc12000-07-08 06:16:37 +0000696 }
697 else
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000698 strncpy(prefix, PREFIX, MAXPATHLEN);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000699
Fred Drakeedabdc12000-07-08 06:16:37 +0000700 if (efound > 0) {
701 reduce(exec_prefix);
702 reduce(exec_prefix);
703 reduce(exec_prefix);
Antoine Pitrouc83ea132010-05-09 14:46:46 +0000704 if (!exec_prefix[0])
705 strcpy(exec_prefix, separator);
Fred Drakeedabdc12000-07-08 06:16:37 +0000706 }
707 else
Jeremy Hylton6372fe12000-09-27 20:51:17 +0000708 strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN);
Guido van Rossum305e5d01997-04-11 17:18:45 +0000709}
710
711
712/* External interface */
Guido van Rossum667d7041995-08-04 04:20:48 +0000713
714char *
Thomas Woutersf3f33dc2000-07-21 06:00:07 +0000715Py_GetPath(void)
Guido van Rossum667d7041995-08-04 04:20:48 +0000716{
Fred Drakeedabdc12000-07-08 06:16:37 +0000717 if (!module_search_path)
718 calculate_path();
719 return module_search_path;
Guido van Rossum667d7041995-08-04 04:20:48 +0000720}
Guido van Rossumc34c9a51996-06-12 04:20:27 +0000721
Guido van Rossumc34c9a51996-06-12 04:20:27 +0000722char *
Thomas Woutersf3f33dc2000-07-21 06:00:07 +0000723Py_GetPrefix(void)
Guido van Rossumc34c9a51996-06-12 04:20:27 +0000724{
Fred Drakeedabdc12000-07-08 06:16:37 +0000725 if (!module_search_path)
726 calculate_path();
727 return prefix;
Guido van Rossumc34c9a51996-06-12 04:20:27 +0000728}
729
730char *
Thomas Woutersf3f33dc2000-07-21 06:00:07 +0000731Py_GetExecPrefix(void)
Guido van Rossumc34c9a51996-06-12 04:20:27 +0000732{
Fred Drakeedabdc12000-07-08 06:16:37 +0000733 if (!module_search_path)
734 calculate_path();
735 return exec_prefix;
Guido van Rossumc34c9a51996-06-12 04:20:27 +0000736}
Guido van Rossum7929c6f1997-05-20 22:38:21 +0000737
738char *
Thomas Woutersf3f33dc2000-07-21 06:00:07 +0000739Py_GetProgramFullPath(void)
Guido van Rossum7929c6f1997-05-20 22:38:21 +0000740{
Fred Drakeedabdc12000-07-08 06:16:37 +0000741 if (!module_search_path)
742 calculate_path();
743 return progpath;
Guido van Rossum7929c6f1997-05-20 22:38:21 +0000744}
Anthony Baxterac6bd462006-04-13 02:06:09 +0000745
746
747#ifdef __cplusplus
748}
749#endif
750