symbian-qemu-0.9.1-12/python-2.6.1/Modules/getpath.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Modules/getpath.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,694 @@
+/* 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
+
+
+#ifndef VERSION
+#define VERSION "2.1"
+#endif
+
+#ifndef VPATH
+#define VPATH "."
+#endif
+
+#ifndef PREFIX
+#  ifdef __VMS
+#    define PREFIX ""
+#  else
+#    define PREFIX "/usr/local"
+#  endif
+#endif
+
+#ifndef EXEC_PREFIX
+#define EXEC_PREFIX PREFIX
+#endif
+
+#ifndef PYTHONPATH
+#define PYTHONPATH PREFIX "/lib/python" VERSION ":" \
+              EXEC_PREFIX "/lib/python" VERSION "/lib-dynload"
+#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;
+static char lib_python[] = "lib/python" VERSION;
+
+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 {
+        getcwd(path, MAXPATHLEN);
+        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 */
+    strcpy(exec_prefix, argv0_path);
+    joinpath(exec_prefix, "Modules/Setup");
+    if (isfile(exec_prefix)) {
+        reduce(exec_prefix);
+        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)
+		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, prog, 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;
+    }
+
+    bufsz += strlen(zip_path) + 1;
+    bufsz += strlen(exec_prefix) + 1;
+
+    /* 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 */
+        strcat(buf, zip_path);
+        strcat(buf, delimiter);
+
+        /* 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);
+                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;
+        }
+        strcat(buf, delimiter);
+
+        /* Finally, on goes the directory for dynamic-load modules */
+        strcat(buf, exec_prefix);
+
+        /* 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
+