| /* Return the initial module search path. */ |
| |
| #include "Python.h" |
| #include "osdefs.h" |
| |
| #include <sys/types.h> |
| #include <string.h> |
| |
| #ifdef __APPLE__ |
| #include <mach-o/dyld.h> |
| #endif |
| |
| /* Search in some common locations for the associated Python libraries. |
| * |
| * Two directories must be found, the platform independent directory |
| * (prefix), containing the common .py and .pyc files, and the platform |
| * dependent directory (exec_prefix), containing the shared library |
| * modules. Note that prefix and exec_prefix can be the same directory, |
| * but for some installations, they are different. |
| * |
| * Py_GetPath() carries out separate searches for prefix and exec_prefix. |
| * Each search tries a number of different locations until a ``landmark'' |
| * file or directory is found. If no prefix or exec_prefix is found, a |
| * warning message is issued and the preprocessor defined PREFIX and |
| * EXEC_PREFIX are used (even though they will not work); python carries on |
| * as best as is possible, but most imports will fail. |
| * |
| * Before any searches are done, the location of the executable is |
| * determined. If argv[0] has one or more slashes in it, it is used |
| * unchanged. Otherwise, it must have been invoked from the shell's path, |
| * so we search $PATH for the named executable and use that. If the |
| * executable was not found on $PATH (or there was no $PATH environment |
| * variable), the original argv[0] string is used. |
| * |
| * Next, the executable location is examined to see if it is a symbolic |
| * link. If so, the link is chased (correctly interpreting a relative |
| * pathname if one is found) and the directory of the link target is used. |
| * |
| * Finally, argv0_path is set to the directory containing the executable |
| * (i.e. the last component is stripped). |
| * |
| * With argv0_path in hand, we perform a number of steps. The same steps |
| * are performed for prefix and for exec_prefix, but with a different |
| * landmark. |
| * |
| * Step 1. Are we running python out of the build directory? This is |
| * checked by looking for a different kind of landmark relative to |
| * argv0_path. For prefix, the landmark's path is derived from the VPATH |
| * preprocessor variable (taking into account that its value is almost, but |
| * not quite, what we need). For exec_prefix, the landmark is |
| * Modules/Setup. If the landmark is found, we're done. |
| * |
| * For the remaining steps, the prefix landmark will always be |
| * lib/python$VERSION/os.py and the exec_prefix will always be |
| * lib/python$VERSION/lib-dynload, where $VERSION is Python's version |
| * number as supplied by the Makefile. Note that this means that no more |
| * build directory checking is performed; if the first step did not find |
| * the landmarks, the assumption is that python is running from an |
| * installed setup. |
| * |
| * Step 2. See if the $PYTHONHOME environment variable points to the |
| * installed location of the Python libraries. If $PYTHONHOME is set, then |
| * it points to prefix and exec_prefix. $PYTHONHOME can be a single |
| * directory, which is used for both, or the prefix and exec_prefix |
| * directories separated by a colon. |
| * |
| * Step 3. Try to find prefix and exec_prefix relative to argv0_path, |
| * backtracking up the path until it is exhausted. This is the most common |
| * step to succeed. Note that if prefix and exec_prefix are different, |
| * exec_prefix is more likely to be found; however if exec_prefix is a |
| * subdirectory of prefix, both will be found. |
| * |
| * Step 4. Search the directories pointed to by the preprocessor variables |
| * PREFIX and EXEC_PREFIX. These are supplied by the Makefile but can be |
| * passed in as options to the configure script. |
| * |
| * That's it! |
| * |
| * Well, almost. Once we have determined prefix and exec_prefix, the |
| * preprocessor variable PYTHONPATH is used to construct a path. Each |
| * relative path on PYTHONPATH is prefixed with prefix. Then the directory |
| * containing the shared library modules is appended. The environment |
| * variable $PYTHONPATH is inserted in front of it all. Finally, the |
| * prefix and exec_prefix globals are tweaked so they reflect the values |
| * expected by other code, by stripping the "lib/python$VERSION/..." stuff |
| * off. If either points to the build directory, the globals are reset to |
| * the corresponding preprocessor variables (so sys.prefix will reflect the |
| * installation location, even though sys.path points into the build |
| * directory). This seems to make more sense given that currently the only |
| * known use of sys.prefix and sys.exec_prefix is for the ILU installation |
| * process to find the installed Python tree. |
| */ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| |
| #if !defined(PREFIX) || !defined(EXEC_PREFIX) || !defined(VERSION) || !defined(VPATH) |
| #error "PREFIX, EXEC_PREFIX, VERSION, and VPATH must be constant defined" |
| #endif |
| |
| #ifndef LANDMARK |
| #define LANDMARK "os.py" |
| #endif |
| |
| static char prefix[MAXPATHLEN+1]; |
| static char exec_prefix[MAXPATHLEN+1]; |
| static char progpath[MAXPATHLEN+1]; |
| static char *module_search_path = NULL; |
| #ifdef ANDROID_LIB_PYTHON_PATH |
| static char lib_python[] = ANDROID_LIB_PYTHON_PATH; |
| #else |
| static char lib_python[] = "lib/python" VERSION; |
| #endif |
| |
| static void |
| reduce(char *dir) |
| { |
| size_t i = strlen(dir); |
| while (i > 0 && dir[i] != SEP) |
| --i; |
| dir[i] = '\0'; |
| } |
| |
| |
| static int |
| isfile(char *filename) /* Is file, not directory */ |
| { |
| struct stat buf; |
| if (stat(filename, &buf) != 0) |
| return 0; |
| if (!S_ISREG(buf.st_mode)) |
| return 0; |
| return 1; |
| } |
| |
| |
| static int |
| ismodule(char *filename) /* Is module -- check for .pyc/.pyo too */ |
| { |
| if (isfile(filename)) |
| return 1; |
| |
| /* Check for the compiled version of prefix. */ |
| if (strlen(filename) < MAXPATHLEN) { |
| strcat(filename, Py_OptimizeFlag ? "o" : "c"); |
| if (isfile(filename)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| |
| static int |
| isxfile(char *filename) /* Is executable file */ |
| { |
| struct stat buf; |
| if (stat(filename, &buf) != 0) |
| return 0; |
| if (!S_ISREG(buf.st_mode)) |
| return 0; |
| if ((buf.st_mode & 0111) == 0) |
| return 0; |
| return 1; |
| } |
| |
| |
| static int |
| isdir(char *filename) /* Is directory */ |
| { |
| struct stat buf; |
| if (stat(filename, &buf) != 0) |
| return 0; |
| if (!S_ISDIR(buf.st_mode)) |
| return 0; |
| return 1; |
| } |
| |
| |
| /* Add a path component, by appending stuff to buffer. |
| buffer must have at least MAXPATHLEN + 1 bytes allocated, and contain a |
| NUL-terminated string with no more than MAXPATHLEN characters (not counting |
| the trailing NUL). It's a fatal error if it contains a string longer than |
| that (callers must be careful!). If these requirements are met, it's |
| guaranteed that buffer will still be a NUL-terminated string with no more |
| than MAXPATHLEN characters at exit. If stuff is too long, only as much of |
| stuff as fits will be appended. |
| */ |
| static void |
| joinpath(char *buffer, char *stuff) |
| { |
| size_t n, k; |
| if (stuff[0] == SEP) |
| n = 0; |
| else { |
| n = strlen(buffer); |
| if (n > 0 && buffer[n-1] != SEP && n < MAXPATHLEN) |
| buffer[n++] = SEP; |
| } |
| if (n > MAXPATHLEN) |
| Py_FatalError("buffer overflow in getpath.c's joinpath()"); |
| k = strlen(stuff); |
| if (n + k > MAXPATHLEN) |
| k = MAXPATHLEN - n; |
| strncpy(buffer+n, stuff, k); |
| buffer[n+k] = '\0'; |
| } |
| |
| /* copy_absolute requires that path be allocated at least |
| MAXPATHLEN + 1 bytes and that p be no more than MAXPATHLEN bytes. */ |
| static void |
| copy_absolute(char *path, char *p) |
| { |
| if (p[0] == SEP) |
| strcpy(path, p); |
| else { |
| if (!getcwd(path, MAXPATHLEN)) { |
| /* unable to get the current directory */ |
| strcpy(path, p); |
| return; |
| } |
| if (p[0] == '.' && p[1] == SEP) |
| p += 2; |
| joinpath(path, p); |
| } |
| } |
| |
| /* absolutize() requires that path be allocated at least MAXPATHLEN+1 bytes. */ |
| static void |
| absolutize(char *path) |
| { |
| char buffer[MAXPATHLEN + 1]; |
| |
| if (path[0] == SEP) |
| return; |
| copy_absolute(buffer, path); |
| strcpy(path, buffer); |
| } |
| |
| /* search_for_prefix requires that argv0_path be no more than MAXPATHLEN |
| bytes long. |
| */ |
| static int |
| search_for_prefix(char *argv0_path, char *home) |
| { |
| size_t n; |
| char *vpath; |
| |
| /* If PYTHONHOME is set, we believe it unconditionally */ |
| if (home) { |
| char *delim; |
| strncpy(prefix, home, MAXPATHLEN); |
| delim = strchr(prefix, DELIM); |
| if (delim) |
| *delim = '\0'; |
| joinpath(prefix, lib_python); |
| joinpath(prefix, LANDMARK); |
| return 1; |
| } |
| |
| /* Check to see if argv[0] is in the build directory */ |
| strcpy(prefix, argv0_path); |
| joinpath(prefix, "Modules/Setup"); |
| if (isfile(prefix)) { |
| /* Check VPATH to see if argv0_path is in the build directory. */ |
| vpath = VPATH; |
| strcpy(prefix, argv0_path); |
| joinpath(prefix, vpath); |
| joinpath(prefix, "Lib"); |
| joinpath(prefix, LANDMARK); |
| if (ismodule(prefix)) |
| return -1; |
| } |
| |
| /* Search from argv0_path, until root is found */ |
| copy_absolute(prefix, argv0_path); |
| do { |
| n = strlen(prefix); |
| joinpath(prefix, lib_python); |
| joinpath(prefix, LANDMARK); |
| if (ismodule(prefix)) |
| return 1; |
| prefix[n] = '\0'; |
| reduce(prefix); |
| } while (prefix[0]); |
| |
| /* Look at configure's PREFIX */ |
| strncpy(prefix, PREFIX, MAXPATHLEN); |
| joinpath(prefix, lib_python); |
| joinpath(prefix, LANDMARK); |
| if (ismodule(prefix)) |
| return 1; |
| |
| /* Fail */ |
| return 0; |
| } |
| |
| |
| /* search_for_exec_prefix requires that argv0_path be no more than |
| MAXPATHLEN bytes long. |
| */ |
| static int |
| search_for_exec_prefix(char *argv0_path, char *home) |
| { |
| size_t n; |
| |
| /* If PYTHONHOME is set, we believe it unconditionally */ |
| if (home) { |
| char *delim; |
| delim = strchr(home, DELIM); |
| if (delim) |
| strncpy(exec_prefix, delim+1, MAXPATHLEN); |
| else |
| strncpy(exec_prefix, home, MAXPATHLEN); |
| joinpath(exec_prefix, lib_python); |
| joinpath(exec_prefix, "lib-dynload"); |
| return 1; |
| } |
| |
| /* Check to see if argv[0] is in the build directory. "pybuilddir.txt" |
| is written by setup.py and contains the relative path to the location |
| of shared library modules. */ |
| strcpy(exec_prefix, argv0_path); |
| joinpath(exec_prefix, "pybuilddir.txt"); |
| if (isfile(exec_prefix)) { |
| FILE *f = fopen(exec_prefix, "r"); |
| if (f == NULL) |
| errno = 0; |
| else { |
| char rel_builddir_path[MAXPATHLEN+1]; |
| size_t n; |
| n = fread(rel_builddir_path, 1, MAXPATHLEN, f); |
| rel_builddir_path[n] = '\0'; |
| fclose(f); |
| strcpy(exec_prefix, argv0_path); |
| joinpath(exec_prefix, rel_builddir_path); |
| return -1; |
| } |
| } |
| |
| /* Search from argv0_path, until root is found */ |
| copy_absolute(exec_prefix, argv0_path); |
| do { |
| n = strlen(exec_prefix); |
| joinpath(exec_prefix, lib_python); |
| joinpath(exec_prefix, "lib-dynload"); |
| if (isdir(exec_prefix)) |
| return 1; |
| exec_prefix[n] = '\0'; |
| reduce(exec_prefix); |
| } while (exec_prefix[0]); |
| |
| /* Look at configure's EXEC_PREFIX */ |
| strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN); |
| joinpath(exec_prefix, lib_python); |
| joinpath(exec_prefix, "lib-dynload"); |
| if (isdir(exec_prefix)) |
| return 1; |
| |
| /* Fail */ |
| return 0; |
| } |
| |
| |
| static void |
| calculate_path(void) |
| { |
| extern char *Py_GetProgramName(void); |
| |
| static char delimiter[2] = {DELIM, '\0'}; |
| static char separator[2] = {SEP, '\0'}; |
| char *pythonpath = PYTHONPATH; |
| char *rtpypath = Py_GETENV("PYTHONPATH"); |
| char *home = Py_GetPythonHome(); |
| char *path = getenv("PATH"); |
| char *prog = Py_GetProgramName(); |
| char argv0_path[MAXPATHLEN+1]; |
| char zip_path[MAXPATHLEN+1]; |
| int pfound, efound; /* 1 if found; -1 if found build directory */ |
| char *buf; |
| size_t bufsz; |
| size_t prefixsz; |
| char *defpath = pythonpath; |
| #ifdef WITH_NEXT_FRAMEWORK |
| NSModule pythonModule; |
| #endif |
| #ifdef __APPLE__ |
| #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4 |
| uint32_t nsexeclength = MAXPATHLEN; |
| #else |
| unsigned long nsexeclength = MAXPATHLEN; |
| #endif |
| #endif |
| |
| /* If there is no slash in the argv0 path, then we have to |
| * assume python is on the user's $PATH, since there's no |
| * other way to find a directory to start the search from. If |
| * $PATH isn't exported, you lose. |
| */ |
| if (strchr(prog, SEP)) |
| strncpy(progpath, prog, MAXPATHLEN); |
| #ifdef __APPLE__ |
| /* On Mac OS X, if a script uses an interpreter of the form |
| * "#!/opt/python2.3/bin/python", the kernel only passes "python" |
| * as argv[0], which falls through to the $PATH search below. |
| * If /opt/python2.3/bin isn't in your path, or is near the end, |
| * this algorithm may incorrectly find /usr/bin/python. To work |
| * around this, we can use _NSGetExecutablePath to get a better |
| * hint of what the intended interpreter was, although this |
| * will fail if a relative path was used. but in that case, |
| * absolutize() should help us out below |
| */ |
| else if(0 == _NSGetExecutablePath(progpath, &nsexeclength) && progpath[0] == SEP) |
| ; |
| #endif /* __APPLE__ */ |
| else if (path) { |
| while (1) { |
| char *delim = strchr(path, DELIM); |
| |
| if (delim) { |
| size_t len = delim - path; |
| if (len > MAXPATHLEN) |
| len = MAXPATHLEN; |
| strncpy(progpath, path, len); |
| *(progpath + len) = '\0'; |
| } |
| else |
| strncpy(progpath, path, MAXPATHLEN); |
| |
| joinpath(progpath, prog); |
| if (isxfile(progpath)) |
| break; |
| |
| if (!delim) { |
| progpath[0] = '\0'; |
| break; |
| } |
| path = delim + 1; |
| } |
| } |
| else |
| progpath[0] = '\0'; |
| if (progpath[0] != SEP && progpath[0] != '\0') |
| absolutize(progpath); |
| strncpy(argv0_path, progpath, MAXPATHLEN); |
| argv0_path[MAXPATHLEN] = '\0'; |
| |
| #ifdef WITH_NEXT_FRAMEWORK |
| /* On Mac OS X we have a special case if we're running from a framework. |
| ** This is because the python home should be set relative to the library, |
| ** which is in the framework, not relative to the executable, which may |
| ** be outside of the framework. Except when we're in the build directory... |
| */ |
| pythonModule = NSModuleForSymbol(NSLookupAndBindSymbol("_Py_Initialize")); |
| /* Use dylib functions to find out where the framework was loaded from */ |
| buf = (char *)NSLibraryNameForModule(pythonModule); |
| if (buf != NULL) { |
| /* We're in a framework. */ |
| /* See if we might be in the build directory. The framework in the |
| ** build directory is incomplete, it only has the .dylib and a few |
| ** needed symlinks, it doesn't have the Lib directories and such. |
| ** If we're running with the framework from the build directory we must |
| ** be running the interpreter in the build directory, so we use the |
| ** build-directory-specific logic to find Lib and such. |
| */ |
| strncpy(argv0_path, buf, MAXPATHLEN); |
| reduce(argv0_path); |
| joinpath(argv0_path, lib_python); |
| joinpath(argv0_path, LANDMARK); |
| if (!ismodule(argv0_path)) { |
| /* We are in the build directory so use the name of the |
| executable - we know that the absolute path is passed */ |
| strncpy(argv0_path, progpath, MAXPATHLEN); |
| } |
| else { |
| /* Use the location of the library as the progpath */ |
| strncpy(argv0_path, buf, MAXPATHLEN); |
| } |
| } |
| #endif |
| |
| #if HAVE_READLINK |
| { |
| char tmpbuffer[MAXPATHLEN+1]; |
| int linklen = readlink(progpath, tmpbuffer, MAXPATHLEN); |
| while (linklen != -1) { |
| /* It's not null terminated! */ |
| tmpbuffer[linklen] = '\0'; |
| if (tmpbuffer[0] == SEP) |
| /* tmpbuffer should never be longer than MAXPATHLEN, |
| but extra check does not hurt */ |
| strncpy(argv0_path, tmpbuffer, MAXPATHLEN); |
| else { |
| /* Interpret relative to progpath */ |
| reduce(argv0_path); |
| joinpath(argv0_path, tmpbuffer); |
| } |
| linklen = readlink(argv0_path, tmpbuffer, MAXPATHLEN); |
| } |
| } |
| #endif /* HAVE_READLINK */ |
| |
| reduce(argv0_path); |
| /* At this point, argv0_path is guaranteed to be less than |
| MAXPATHLEN bytes long. |
| */ |
| |
| if (!(pfound = search_for_prefix(argv0_path, home))) { |
| if (!Py_FrozenFlag) |
| fprintf(stderr, |
| "Could not find platform independent libraries <prefix>\n"); |
| strncpy(prefix, PREFIX, MAXPATHLEN); |
| joinpath(prefix, lib_python); |
| } |
| else |
| reduce(prefix); |
| |
| strncpy(zip_path, prefix, MAXPATHLEN); |
| zip_path[MAXPATHLEN] = '\0'; |
| if (pfound > 0) { /* Use the reduced prefix returned by Py_GetPrefix() */ |
| reduce(zip_path); |
| reduce(zip_path); |
| } |
| else |
| strncpy(zip_path, PREFIX, MAXPATHLEN); |
| joinpath(zip_path, "lib/python00.zip"); |
| bufsz = strlen(zip_path); /* Replace "00" with version */ |
| zip_path[bufsz - 6] = VERSION[0]; |
| zip_path[bufsz - 5] = VERSION[2]; |
| |
| if (!(efound = search_for_exec_prefix(argv0_path, home))) { |
| if (!Py_FrozenFlag) |
| fprintf(stderr, |
| "Could not find platform dependent libraries <exec_prefix>\n"); |
| strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN); |
| joinpath(exec_prefix, "lib/lib-dynload"); |
| } |
| /* If we found EXEC_PREFIX do *not* reduce it! (Yet.) */ |
| |
| if ((!pfound || !efound) && !Py_FrozenFlag) |
| fprintf(stderr, |
| "Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]\n"); |
| |
| /* Calculate size of return buffer. |
| */ |
| bufsz = 0; |
| |
| if (rtpypath) |
| bufsz += strlen(rtpypath) + 1; |
| |
| prefixsz = strlen(prefix) + 1; |
| |
| while (1) { |
| char *delim = strchr(defpath, DELIM); |
| |
| if (defpath[0] != SEP) |
| /* Paths are relative to prefix */ |
| bufsz += prefixsz; |
| |
| if (delim) |
| bufsz += delim - defpath + 1; |
| else { |
| bufsz += strlen(defpath) + 1; |
| break; |
| } |
| defpath = delim + 1; |
| } |
| |
| #ifndef ANDROID_SKIP_ZIP_PATH |
| bufsz += strlen(zip_path) + 1; |
| #endif |
| #ifndef ANDROID_SKIP_EXEC_PREFIX_PATH |
| bufsz += strlen(exec_prefix) + 1; |
| #endif |
| |
| /* This is the only malloc call in this file */ |
| buf = (char *)PyMem_Malloc(bufsz); |
| |
| if (buf == NULL) { |
| /* We can't exit, so print a warning and limp along */ |
| fprintf(stderr, "Not enough memory for dynamic PYTHONPATH.\n"); |
| fprintf(stderr, "Using default static PYTHONPATH.\n"); |
| module_search_path = PYTHONPATH; |
| } |
| else { |
| /* Run-time value of $PYTHONPATH goes first */ |
| if (rtpypath) { |
| strcpy(buf, rtpypath); |
| strcat(buf, delimiter); |
| } |
| else |
| buf[0] = '\0'; |
| |
| /* Next is the default zip path */ |
| #ifndef ANDROID_SKIP_ZIP_PATH |
| strcat(buf, zip_path); |
| strcat(buf, delimiter); |
| #endif |
| |
| /* Next goes merge of compile-time $PYTHONPATH with |
| * dynamically located prefix. |
| */ |
| defpath = pythonpath; |
| while (1) { |
| char *delim = strchr(defpath, DELIM); |
| |
| if (defpath[0] != SEP) { |
| strcat(buf, prefix); |
| if (prefixsz >= 2 && prefix[prefixsz - 2] != SEP && |
| defpath[0] != (delim ? DELIM : L'\0')) { /* not empty */ |
| strcat(buf, separator); |
| } |
| } |
| |
| if (delim) { |
| size_t len = delim - defpath + 1; |
| size_t end = strlen(buf) + len; |
| strncat(buf, defpath, len); |
| *(buf + end) = '\0'; |
| } |
| else { |
| strcat(buf, defpath); |
| break; |
| } |
| defpath = delim + 1; |
| } |
| #ifndef ANDROID_SKIP_EXEC_PREFIX_PATH |
| strcat(buf, delimiter); |
| |
| /* Finally, on goes the directory for dynamic-load modules */ |
| strcat(buf, exec_prefix); |
| #endif |
| |
| /* And publish the results */ |
| module_search_path = buf; |
| } |
| |
| /* Reduce prefix and exec_prefix to their essence, |
| * e.g. /usr/local/lib/python1.5 is reduced to /usr/local. |
| * If we're loading relative to the build directory, |
| * return the compiled-in defaults instead. |
| */ |
| if (pfound > 0) { |
| reduce(prefix); |
| reduce(prefix); |
| /* The prefix is the root directory, but reduce() chopped |
| * off the "/". */ |
| if (!prefix[0]) |
| strcpy(prefix, separator); |
| } |
| else |
| strncpy(prefix, PREFIX, MAXPATHLEN); |
| |
| if (efound > 0) { |
| reduce(exec_prefix); |
| reduce(exec_prefix); |
| reduce(exec_prefix); |
| if (!exec_prefix[0]) |
| strcpy(exec_prefix, separator); |
| } |
| else |
| strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN); |
| } |
| |
| |
| /* External interface */ |
| |
| char * |
| Py_GetPath(void) |
| { |
| if (!module_search_path) |
| calculate_path(); |
| return module_search_path; |
| } |
| |
| char * |
| Py_GetPrefix(void) |
| { |
| if (!module_search_path) |
| calculate_path(); |
| return prefix; |
| } |
| |
| char * |
| Py_GetExecPrefix(void) |
| { |
| if (!module_search_path) |
| calculate_path(); |
| return exec_prefix; |
| } |
| |
| char * |
| Py_GetProgramFullPath(void) |
| { |
| if (!module_search_path) |
| calculate_path(); |
| return progpath; |
| } |
| |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
