getpath.c

来自「python s60 1.4.5版本的源代码」· C语言 代码 · 共 665 行 · 第 1/2 页

        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];
    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

	/* 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);
	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 = 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);

    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(exec_prefix) + 1;

    /* This is the only malloc call in this file */
    buf = 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 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);
    }
    else
        strncpy(prefix, PREFIX, MAXPATHLEN);

    if (efound > 0) {
        reduce(exec_prefix);
        reduce(exec_prefix);
        reduce(exec_prefix);
    }
    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;
}
#else /* SYMBIAN */
const static char *const prefix = "\0";
const static char *const progpath = "\0";

/* External interface */

/* We'd like to get this from CSPyInterpreter.h but that's a C++ header... */
extern char* SPy_get_path(void);
DL_EXPORT(char *)
Py_GetPath(void)
{
  return SPy_get_path();
}

DL_EXPORT(char *)
Py_GetPrefix(void)
{
  // XXX:CW32
  return (char *)prefix;
}

DL_EXPORT(char *)
Py_GetExecPrefix(void)
{
  return Py_GetPrefix();
}

DL_EXPORT(char *)
Py_GetProgramFullPath(void)
{
  // XXX:CW32
  return (char *)progpath;
}
#endif /* SYMBIAN */