import.c

python s60 1.4.5版本的源代码

	Py_DECREF(m); /* Yes, it still exists, in modules! */

	return m;
}


/* Execute a code object in a module and return the module object
   WITH INCREMENTED REFERENCE COUNT */

DL_EXPORT(PyObject *)
PyImport_ExecCodeModule(char *name, PyObject *co)
{
	return PyImport_ExecCodeModuleEx(name, co, (char *)NULL);
}

DL_EXPORT(PyObject *)
PyImport_ExecCodeModuleEx(char *name, PyObject *co, char *pathname)
{
	PyObject *modules = PyImport_GetModuleDict();
	PyObject *m, *d, *v;

	m = PyImport_AddModule(name);
	if (m == NULL)
		return NULL;
	d = PyModule_GetDict(m);
	if (PyDict_GetItemString(d, "__builtins__") == NULL) {
		if (PyDict_SetItemString(d, "__builtins__",
					 PyEval_GetBuiltins()) != 0)
			return NULL;
	}
	/* Remember the filename as the __file__ attribute */
	v = NULL;
	if (pathname != NULL) {
		v = PyString_FromString(pathname);
		if (v == NULL)
			PyErr_Clear();
	}
	if (v == NULL) {
		v = ((PyCodeObject *)co)->co_filename;
		Py_INCREF(v);
	}
	if (PyDict_SetItemString(d, "__file__", v) != 0)
		PyErr_Clear(); /* Not important enough to report */
	Py_DECREF(v);

	v = PyEval_EvalCode((PyCodeObject *)co, d, d);
	if (v == NULL)
		return NULL;
	Py_DECREF(v);

	if ((m = PyDict_GetItemString(modules, name)) == NULL) {
		PyErr_Format(PyExc_ImportError,
			     "Loaded module %.200s not found in sys.modules",
			     name);
		return NULL;
	}

	Py_INCREF(m);

	return m;
}


/* Given a pathname for a Python source file, fill a buffer with the
   pathname for the corresponding compiled file.  Return the pathname
   for the compiled file, or NULL if there's no space in the buffer.
   Doesn't set an exception. */

static char *
make_compiled_pathname(char *pathname, char *buf, size_t buflen)
{
	size_t len = strlen(pathname);
	if (len+2 > buflen)
		return NULL;

#ifdef MS_WIN32
	/* Treat .pyw as if it were .py.  The case of ".pyw" must match
	   that used in _PyImport_StandardFiletab. */
	if (len >= 4 && strcmp(&pathname[len-4], ".pyw") == 0)
		--len;	/* pretend 'w' isn't there */
#endif
	memcpy(buf, pathname, len);
	buf[len] = Py_OptimizeFlag ? 'o' : 'c';
	buf[len+1] = '\0';

	return buf;
}


/* Given a pathname for a Python source file, its time of last
   modification, and a pathname for a compiled file, check whether the
   compiled file represents the same version of the source.  If so,
   return a FILE pointer for the compiled file, positioned just after
   the header; if not, return NULL.
   Doesn't set an exception. */

static FILE *
check_compiled_module(char *pathname, long mtime, char *cpathname)
{
	FILE *fp;
	long magic;
	long pyc_mtime;

	fp = fopen(cpathname, "rb");
	if (fp == NULL)
		return NULL;
	magic = PyMarshal_ReadLongFromFile(fp);
	if (magic != pyc_magic) {
		if (Py_VerboseFlag)
			PySys_WriteStderr("# %s has bad magic\n", cpathname);
		fclose(fp);
		return NULL;
	}
	pyc_mtime = PyMarshal_ReadLongFromFile(fp);
	if (pyc_mtime != mtime) {
		if (Py_VerboseFlag)
			PySys_WriteStderr("# %s has bad mtime\n", cpathname);
		fclose(fp);
		return NULL;
	}
	if (Py_VerboseFlag)
		PySys_WriteStderr("# %s matches %s\n", cpathname, pathname);
	return fp;
}


/* Read a code object from a file and check it for validity */

static PyCodeObject *
read_compiled_module(char *cpathname, FILE *fp)
{
	PyObject *co;

	co = PyMarshal_ReadLastObjectFromFile(fp);
	/* Ugly: rd_object() may return NULL with or without error */
	if (co == NULL || !PyCode_Check(co)) {
		if (!PyErr_Occurred())
			PyErr_Format(PyExc_ImportError,
			    "Non-code object in %.200s", cpathname);
		Py_XDECREF(co);
		return NULL;
	}
	return (PyCodeObject *)co;
}


/* Load a module from a compiled file, execute it, and return its
   module object WITH INCREMENTED REFERENCE COUNT */

static PyObject *
load_compiled_module(char *name, char *cpathname, FILE *fp)
{
	long magic;
	PyCodeObject *co;
	PyObject *m;

	magic = PyMarshal_ReadLongFromFile(fp);
	if (magic != pyc_magic) {
		PyErr_Format(PyExc_ImportError,
			     "Bad magic number in %.200s", cpathname);
		return NULL;
	}
	(void) PyMarshal_ReadLongFromFile(fp);
	co = read_compiled_module(cpathname, fp);
	if (co == NULL)
		return NULL;
	if (Py_VerboseFlag)
		PySys_WriteStderr("import %s # precompiled from %s\n",
			name, cpathname);
	m = PyImport_ExecCodeModuleEx(name, (PyObject *)co, cpathname);
	Py_DECREF(co);

	return m;
}

/* Parse a source file and return the corresponding code object */

static PyCodeObject *
parse_source_module(char *pathname, FILE *fp)
{
	PyCodeObject *co;
	node *n;

	n = PyParser_SimpleParseFile(fp, pathname, Py_file_input);
	if (n == NULL)
		return NULL;
	co = PyNode_Compile(n, pathname);
	PyNode_Free(n);

	return co;
}

#ifndef SYMBIAN
/* Helper to open a bytecode file for writing in exclusive mode */

static FILE *
open_exclusive(char *filename)
{
#if defined(O_EXCL)&&defined(O_CREAT)&&defined(O_WRONLY)&&defined(O_TRUNC)
	/* Use O_EXCL to avoid a race condition when another process tries to
	   write the same file.  When that happens, our open() call fails,
	   which is just fine (since it's only a cache).
	   XXX If the file exists and is writable but the directory is not
	   writable, the file will never be written.  Oh well.
	*/
	int fd;
	(void) unlink(filename);
	fd = open(filename, O_EXCL|O_CREAT|O_WRONLY|O_TRUNC
#ifdef O_BINARY
				|O_BINARY   /* necessary for Windows */
#endif

			, 0666);
	if (fd < 0)
		return NULL;
	return fdopen(fd, "wb");
#else
	/* Best we can do -- on Windows this can't happen anyway */
	return fopen(filename, "wb");
#endif
}

/* Write a compiled module to a file, placing the time of last
   modification of its source into the header.
   Errors are ignored, if a write error occurs an attempt is made to
   remove the file. */

static void
write_compiled_module(PyCodeObject *co, char *cpathname, long mtime)
{
	FILE *fp;

	if (CANT_WRITE(co->co_argcount) ||
	    CANT_WRITE(co->co_nlocals) ||
	    CANT_WRITE(co->co_stacksize) ||
	    CANT_WRITE(co->co_flags) ||
	    CANT_WRITE(co->co_firstlineno)) {
		if (Py_VerboseFlag)
			PySys_WriteStderr(
				"# code too large: can't write %s\n",
				cpathname);
		return;
	}

	fp = open_exclusive(cpathname);
	if (fp == NULL) {
		if (Py_VerboseFlag)
			PySys_WriteStderr(
				"# can't create %s\n", cpathname);
		return;
	}
	PyMarshal_WriteLongToFile(pyc_magic, fp);
#ifndef SYMBIAN
	/* First write a 0 for mtime */
	PyMarshal_WriteLongToFile(0L, fp);
#else
	PyMarshal_WriteLongToFile(mtime, fp);
#endif
	PyMarshal_WriteObjectToFile((PyObject *)co, fp);
	if (ferror(fp)) {
		if (Py_VerboseFlag)
			PySys_WriteStderr("# can't write %s\n", cpathname);
		/* Don't keep partial file */
		fclose(fp);
		(void) unlink(cpathname);
		return;
	}
#ifndef SYMBIAN
	/* Now write the true mtime */
	fseek(fp, 4L, 0);
	PyMarshal_WriteLongToFile(mtime, fp);
#endif
	fflush(fp);
	fclose(fp);
	if (Py_VerboseFlag)
		PySys_WriteStderr("# wrote %s\n", cpathname);
#ifdef macintosh
	PyMac_setfiletype(cpathname, 'Pyth', 'PYC ');
#endif
}
#endif /* SYMBIAN */

/* Load a source module from a given file and return its module
   object WITH INCREMENTED REFERENCE COUNT.  If there's a matching
   byte-compiled file, use that instead. */

static PyObject *
load_source_module(char *name, char *pathname, FILE *fp)
{
	time_t mtime;
	FILE *fpc;
	char buf[MAXPATHLEN+1];
	char *cpathname;
	PyCodeObject *co;
	PyObject *m;

	mtime = PyOS_GetLastModificationTime(pathname, fp);
	if (mtime == (time_t)(-1)) 
	  /* It is possible for the time to be beyond the range of
	   * UNIX time, which will cause fstat() to fail. Such
	   * timestamps are sometimes created when transferring files
	   * to the phone. It's unclear if this is a firmware bug or a
	   * bug in the file transmission software.
	   *
	   * For convenience we work around the problem by just
	   * swallowing the error and assuming the file is old if we
	   * PyOS_GetLastModificationTime fails. This is of no major
	   * consequence since we don't save .pyc's dynamically.
	   */
	  mtime=0;
#if SIZEOF_TIME_T > 4
	/* Python's .pyc timestamp handling presumes that the timestamp fits
	   in 4 bytes. This will be fine until sometime in the year 2038,
	   when a 4-byte signed time_t will overflow.
	 */
	if (mtime >> 32) {
		PyErr_SetString(PyExc_OverflowError,
			"modification time overflows a 4 byte field");
		return NULL;
	}
#endif
	cpathname = make_compiled_pathname(pathname, buf,
					   (size_t)MAXPATHLEN + 1);
	if (cpathname != NULL &&
	    (fpc = check_compiled_module(pathname, mtime, cpathname))) {
		co = read_compiled_module(cpathname, fpc);
		fclose(fpc);
		if (co == NULL)
			return NULL;
		if (Py_VerboseFlag)
			PySys_WriteStderr("import %s # precompiled from %s\n",
				name, cpathname);
		pathname = cpathname;
	}
	else {
		co = parse_source_module(pathname, fp);
		if (co == NULL)
			return NULL;
		if (Py_VerboseFlag)
			PySys_WriteStderr("import %s # from %s\n",
				name, pathname);
#if !defined SYMBIAN
		write_compiled_module(co, cpathname, mtime);
#endif
	}
	m = PyImport_ExecCodeModuleEx(name, (PyObject *)co, pathname);
	Py_DECREF(co);

	return m;
}


/* Forward */
static PyObject *load_module(char *, FILE *, char *, int);
static struct filedescr *find_module(char *, PyObject *,
				     char *, size_t, FILE **);
static struct _frozen *find_frozen(char *name);

/* Load a package and return its module object WITH INCREMENTED
   REFERENCE COUNT */

static PyObject *
load_package(char *name, char *pathname)
{
	PyObject *m, *d, *file, *path;
	int err;
	char buf[MAXPATHLEN+1];
	FILE *fp = NULL;
	struct filedescr *fdp;

	m = PyImport_AddModule(name);
	if (m == NULL)
		return NULL;
	if (Py_VerboseFlag)
		PySys_WriteStderr("import %s # directory %s\n",
			name, pathname);
	d = PyModule_GetDict(m);
	file = PyString_FromString(pathname);
	if (file == NULL)
		return NULL;
	path = Py_BuildValue("[O]", file);
	if (path == NULL) {
		Py_DECREF(file);
		return NULL;
	}
	err = PyDict_SetItemString(d, "__file__", file);
	if (err == 0)
		err = PyDict_SetItemString(d, "__path__", path);
	if (err != 0) {
		m = NULL;
		goto cleanup;
	}
	buf[0] = '\0';
	fdp = find_module("__init__", path, buf, sizeof(buf), &fp);
	if (fdp == NULL) {
		if (PyErr_ExceptionMatches(PyExc_ImportError)) {
			PyErr_Clear();
		}
		else
			m = NULL;
		goto cleanup;
	}
	m = load_module(name, fp, buf, fdp->type);
	if (fp != NULL)
		fclose(fp);
  cleanup:
	Py_XDECREF(path);
	Py_XDECREF(file);
	return m;
}


/* Helper to test for built-in module */

static int
is_builtin(char *name)
{
	int i;
	for (i = 0; PyImport_Inittab[i].name != NULL; i++) {
		if (strcmp(name, PyImport_Inittab[i].name) == 0) {
			if (PyImport_Inittab[i].initfunc == NULL)
				return -1;
			else
				return 1;
		}
	}
	return 0;
}


/* Search the path (default sys.path) for a module.  Return the
   corresponding filedescr struct, and (via return arguments) the
   pathname and an open file.  Return NULL if the module is not found. */

#ifdef MS_COREDLL
extern FILE *PyWin_FindRegisteredModule(const char *, struct filedescr **,
					char *, int);
#endif

static int case_ok(char *, int, int, char *);
static int find_init_module(char *); /* Forward */

static struct filedescr *
find_module(char *realname, PyObject *path, char *buf, size_t buflen,
	    FILE **p_fp)
{
	int i, npath;
	size_t len, namelen;
	struct filedescr *fdp = NULL;
	FILE *fp = NULL;
#ifndef RISCOS
	struct stat statbuf;
#endif
	char name[MAXPATHLEN+1];
#ifndef SYMBIAN
	static struct filedescr fd_frozen = {"", "", PY_FROZEN};
	static struct filedescr fd_builtin = {"", "", C_BUILTIN};
	static struct filedescr fd_package = {"", "", PKG_DIRECTORY};
#else
	SPy_Python_globals* pyglobals = PYTHON_GLOBALS; // avoid TLS calls
#define fd_frozen (pyglobals->imp_fd_frozen)
#define fd_builtin (pyglobals->imp_fd_builtin)
#define fd_package (pyglobals->imp_fd_package)
	if (fd_frozen.type == UNINITIALIZED) {
	  fd_frozen.suffix = "";
	  fd_frozen.mode = "";
	  fd_frozen.type = PY_FROZEN;
	}

	if (fd_builtin.type == UNINITIALIZED) {
	  fd_builtin.suffix = "";
	  fd_builtin.mode = "";
	  fd_builtin.type = C_BUILTIN;
	}

	if (fd_package.type == UNINITIALIZED) {
	  fd_package.suffix = "";
	  fd_package.mode = "";
	  fd_package.type = PKG_DIRECTORY;
	}
#endif /* SYMBIAN */

	if (strlen(realname) > MAXPATHLEN) {
		PyErr_SetString(PyExc_OverflowError,
				"module name is too long");
		return NULL;
	}
	strcpy(name, realname);

	if (path != NULL && PyString_Check(path)) {
		/* The only type of submodule allowed inside a "frozen"
		   package are other frozen modules or packages. */
		if (PyString_Size(path) + 1 + strlen(name) >= (size_t)buflen) {
			PyErr_SetString(PyExc_ImportError,
					"full frozen module name too long");
			return NULL;
		}
		strcpy(buf, PyString_AsString(path));
		strcat(buf, ".");
		strcat(buf, name);
		strcpy(name, buf);
#ifdef macintosh
		/* Freezing on the mac works different, and the modules are
		** actually on sys.path. So we don't take the quick exit but
		** continue with the normal flow.
		*/
		path = NULL;
#else
		if (find_frozen(name) != NULL) {
			strcpy(buf, name);
			return &fd_frozen;
		}
		PyErr_Format(PyExc_ImportError,
			     "No frozen submodule named %.200s", name);