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import.c
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3391 lines (3026 loc) · 83.3 KB
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/* Module definition and import implementation */
#include "Python.h"
#include "Python-ast.h"
#undef Yield /* undefine macro conflicting with winbase.h */
#include "pyarena.h"
#include "pythonrun.h"
#include "errcode.h"
#include "marshal.h"
#include "code.h"
#include "compile.h"
#include "eval.h"
#include "osdefs.h"
#include "importdl.h"
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif
#ifdef MS_WINDOWS
/* for stat.st_mode */
typedef unsigned short mode_t;
#endif
/* Magic word to reject .pyc files generated by other Python versions.
It should change for each incompatible change to the bytecode.
The value of CR and LF is incorporated so if you ever read or write
a .pyc file in text mode the magic number will be wrong; also, the
Apple MPW compiler swaps their values, botching string constants.
The magic numbers must be spaced apart atleast 2 values, as the
-U interpeter flag will cause MAGIC+1 being used. They have been
odd numbers for some time now.
There were a variety of old schemes for setting the magic number.
The current working scheme is to increment the previous value by
10.
Known values:
Python 1.5: 20121
Python 1.5.1: 20121
Python 1.5.2: 20121
Python 1.6: 50428
Python 2.0: 50823
Python 2.0.1: 50823
Python 2.1: 60202
Python 2.1.1: 60202
Python 2.1.2: 60202
Python 2.2: 60717
Python 2.3a0: 62011
Python 2.3a0: 62021
Python 2.3a0: 62011 (!)
Python 2.4a0: 62041
Python 2.4a3: 62051
Python 2.4b1: 62061
Python 2.5a0: 62071
Python 2.5a0: 62081 (ast-branch)
Python 2.5a0: 62091 (with)
Python 2.5a0: 62092 (changed WITH_CLEANUP opcode)
Python 2.5b3: 62101 (fix wrong code: for x, in ...)
Python 2.5b3: 62111 (fix wrong code: x += yield)
Python 2.5c1: 62121 (fix wrong lnotab with for loops and
storing constants that should have been removed)
Python 2.5c2: 62131 (fix wrong code: for x, in ... in listcomp/genexp)
Python 2.6a0: 62151 (peephole optimizations and STORE_MAP opcode)
Python 2.6a1: 62161 (WITH_CLEANUP optimization)
Python 2.7a0: 62171 (optimize list comprehensions/change LIST_APPEND)
.
*/
#define MAGIC (62171 | ((long)'\r'<<16) | ((long)'\n'<<24))
/* Magic word as global; note that _PyImport_Init() can change the
value of this global to accommodate for alterations of how the
compiler works which are enabled by command line switches. */
static long pyc_magic = MAGIC;
/* See _PyImport_FixupExtension() below */
static PyObject *extensions = NULL;
/* This table is defined in config.c: */
extern struct _inittab _PyImport_Inittab[];
struct _inittab *PyImport_Inittab = _PyImport_Inittab;
/* these tables define the module suffixes that Python recognizes */
struct filedescr * _PyImport_Filetab = NULL;
#ifdef RISCOS
static const struct filedescr _PyImport_StandardFiletab[] = {
{"/py", "U", PY_SOURCE},
{"/pyc", "rb", PY_COMPILED},
{0, 0}
};
#else
static const struct filedescr _PyImport_StandardFiletab[] = {
{".py", "U", PY_SOURCE},
#ifdef MS_WINDOWS
{".pyw", "U", PY_SOURCE},
#endif
{".pyc", "rb", PY_COMPILED},
{0, 0}
};
#endif
/* Initialize things */
void
_PyImport_Init(void)
{
const struct filedescr *scan;
struct filedescr *filetab;
int countD = 0;
int countS = 0;
/* prepare _PyImport_Filetab: copy entries from
_PyImport_DynLoadFiletab and _PyImport_StandardFiletab.
*/
#ifdef HAVE_DYNAMIC_LOADING
for (scan = _PyImport_DynLoadFiletab; scan->suffix != NULL; ++scan)
++countD;
#endif
for (scan = _PyImport_StandardFiletab; scan->suffix != NULL; ++scan)
++countS;
filetab = PyMem_NEW(struct filedescr, countD + countS + 1);
if (filetab == NULL)
Py_FatalError("Can't initialize import file table.");
#ifdef HAVE_DYNAMIC_LOADING
memcpy(filetab, _PyImport_DynLoadFiletab,
countD * sizeof(struct filedescr));
#endif
memcpy(filetab + countD, _PyImport_StandardFiletab,
countS * sizeof(struct filedescr));
filetab[countD + countS].suffix = NULL;
_PyImport_Filetab = filetab;
if (Py_OptimizeFlag) {
/* Replace ".pyc" with ".pyo" in _PyImport_Filetab */
for (; filetab->suffix != NULL; filetab++) {
#ifndef RISCOS
if (strcmp(filetab->suffix, ".pyc") == 0)
filetab->suffix = ".pyo";
#else
if (strcmp(filetab->suffix, "/pyc") == 0)
filetab->suffix = "/pyo";
#endif
}
}
if (Py_UnicodeFlag) {
/* Fix the pyc_magic so that byte compiled code created
using the all-Unicode method doesn't interfere with
code created in normal operation mode. */
pyc_magic = MAGIC + 1;
}
}
void
_PyImportHooks_Init(void)
{
PyObject *v, *path_hooks = NULL, *zimpimport;
int err = 0;
/* adding sys.path_hooks and sys.path_importer_cache, setting up
zipimport */
if (PyType_Ready(&PyNullImporter_Type) < 0)
goto error;
if (Py_VerboseFlag)
PySys_WriteStderr("# installing zipimport hook\n");
v = PyList_New(0);
if (v == NULL)
goto error;
err = PySys_SetObject("meta_path", v);
Py_DECREF(v);
if (err)
goto error;
v = PyDict_New();
if (v == NULL)
goto error;
err = PySys_SetObject("path_importer_cache", v);
Py_DECREF(v);
if (err)
goto error;
path_hooks = PyList_New(0);
if (path_hooks == NULL)
goto error;
err = PySys_SetObject("path_hooks", path_hooks);
if (err) {
error:
PyErr_Print();
Py_FatalError("initializing sys.meta_path, sys.path_hooks, "
"path_importer_cache, or NullImporter failed"
);
}
zimpimport = PyImport_ImportModule("zipimport");
if (zimpimport == NULL) {
PyErr_Clear(); /* No zip import module -- okay */
if (Py_VerboseFlag)
PySys_WriteStderr("# can't import zipimport\n");
}
else {
PyObject *zipimporter = PyObject_GetAttrString(zimpimport,
"zipimporter");
Py_DECREF(zimpimport);
if (zipimporter == NULL) {
PyErr_Clear(); /* No zipimporter object -- okay */
if (Py_VerboseFlag)
PySys_WriteStderr(
"# can't import zipimport.zipimporter\n");
}
else {
/* sys.path_hooks.append(zipimporter) */
err = PyList_Append(path_hooks, zipimporter);
Py_DECREF(zipimporter);
if (err)
goto error;
if (Py_VerboseFlag)
PySys_WriteStderr(
"# installed zipimport hook\n");
}
}
Py_DECREF(path_hooks);
}
void
_PyImport_Fini(void)
{
Py_XDECREF(extensions);
extensions = NULL;
PyMem_DEL(_PyImport_Filetab);
_PyImport_Filetab = NULL;
}
/* Locking primitives to prevent parallel imports of the same module
in different threads to return with a partially loaded module.
These calls are serialized by the global interpreter lock. */
#ifdef WITH_THREAD
#include "pythread.h"
static PyThread_type_lock import_lock = 0;
static long import_lock_thread = -1;
static int import_lock_level = 0;
static void
lock_import(void)
{
long me = PyThread_get_thread_ident();
if (me == -1)
return; /* Too bad */
if (import_lock == NULL) {
import_lock = PyThread_allocate_lock();
if (import_lock == NULL)
return; /* Nothing much we can do. */
}
if (import_lock_thread == me) {
import_lock_level++;
return;
}
if (import_lock_thread != -1 || !PyThread_acquire_lock(import_lock, 0))
{
PyThreadState *tstate = PyEval_SaveThread();
PyThread_acquire_lock(import_lock, 1);
PyEval_RestoreThread(tstate);
}
import_lock_thread = me;
import_lock_level = 1;
}
static int
unlock_import(void)
{
long me = PyThread_get_thread_ident();
if (me == -1 || import_lock == NULL)
return 0; /* Too bad */
if (import_lock_thread != me)
return -1;
import_lock_level--;
if (import_lock_level == 0) {
import_lock_thread = -1;
PyThread_release_lock(import_lock);
}
return 1;
}
/* This function is called from PyOS_AfterFork to ensure that newly
created child processes do not share locks with the parent. */
void
_PyImport_ReInitLock(void)
{
#ifdef _AIX
if (import_lock != NULL)
import_lock = PyThread_allocate_lock();
#endif
}
#else
#define lock_import()
#define unlock_import() 0
#endif
static PyObject *
imp_lock_held(PyObject *self, PyObject *noargs)
{
#ifdef WITH_THREAD
return PyBool_FromLong(import_lock_thread != -1);
#else
return PyBool_FromLong(0);
#endif
}
static PyObject *
imp_acquire_lock(PyObject *self, PyObject *noargs)
{
#ifdef WITH_THREAD
lock_import();
#endif
Py_INCREF(Py_None);
return Py_None;
}
static PyObject *
imp_release_lock(PyObject *self, PyObject *noargs)
{
#ifdef WITH_THREAD
if (unlock_import() < 0) {
PyErr_SetString(PyExc_RuntimeError,
"not holding the import lock");
return NULL;
}
#endif
Py_INCREF(Py_None);
return Py_None;
}
static void
imp_modules_reloading_clear(void)
{
PyInterpreterState *interp = PyThreadState_Get()->interp;
if (interp->modules_reloading != NULL)
PyDict_Clear(interp->modules_reloading);
}
/* Helper for sys */
PyObject *
PyImport_GetModuleDict(void)
{
PyInterpreterState *interp = PyThreadState_GET()->interp;
if (interp->modules == NULL)
Py_FatalError("PyImport_GetModuleDict: no module dictionary!");
return interp->modules;
}
/* List of names to clear in sys */
static char* sys_deletes[] = {
"path", "argv", "ps1", "ps2", "exitfunc",
"exc_type", "exc_value", "exc_traceback",
"last_type", "last_value", "last_traceback",
"path_hooks", "path_importer_cache", "meta_path",
/* misc stuff */
"flags", "float_info",
NULL
};
static char* sys_files[] = {
"stdin", "__stdin__",
"stdout", "__stdout__",
"stderr", "__stderr__",
NULL
};
/* Un-initialize things, as good as we can */
void
PyImport_Cleanup(void)
{
Py_ssize_t pos, ndone;
char *name;
PyObject *key, *value, *dict;
PyInterpreterState *interp = PyThreadState_GET()->interp;
PyObject *modules = interp->modules;
if (modules == NULL)
return; /* Already done */
/* Delete some special variables first. These are common
places where user values hide and people complain when their
destructors fail. Since the modules containing them are
deleted *last* of all, they would come too late in the normal
destruction order. Sigh. */
value = PyDict_GetItemString(modules, "__builtin__");
if (value != NULL && PyModule_Check(value)) {
dict = PyModule_GetDict(value);
if (Py_VerboseFlag)
PySys_WriteStderr("# clear __builtin__._\n");
PyDict_SetItemString(dict, "_", Py_None);
}
value = PyDict_GetItemString(modules, "sys");
if (value != NULL && PyModule_Check(value)) {
char **p;
PyObject *v;
dict = PyModule_GetDict(value);
for (p = sys_deletes; *p != NULL; p++) {
if (Py_VerboseFlag)
PySys_WriteStderr("# clear sys.%s\n", *p);
PyDict_SetItemString(dict, *p, Py_None);
}
for (p = sys_files; *p != NULL; p+=2) {
if (Py_VerboseFlag)
PySys_WriteStderr("# restore sys.%s\n", *p);
v = PyDict_GetItemString(dict, *(p+1));
if (v == NULL)
v = Py_None;
PyDict_SetItemString(dict, *p, v);
}
}
/* First, delete __main__ */
value = PyDict_GetItemString(modules, "__main__");
if (value != NULL && PyModule_Check(value)) {
if (Py_VerboseFlag)
PySys_WriteStderr("# cleanup __main__\n");
_PyModule_Clear(value);
PyDict_SetItemString(modules, "__main__", Py_None);
}
/* The special treatment of __builtin__ here is because even
when it's not referenced as a module, its dictionary is
referenced by almost every module's __builtins__. Since
deleting a module clears its dictionary (even if there are
references left to it), we need to delete the __builtin__
module last. Likewise, we don't delete sys until the very
end because it is implicitly referenced (e.g. by print).
Also note that we 'delete' modules by replacing their entry
in the modules dict with None, rather than really deleting
them; this avoids a rehash of the modules dictionary and
also marks them as "non existent" so they won't be
re-imported. */
/* Next, repeatedly delete modules with a reference count of
one (skipping __builtin__ and sys) and delete them */
do {
ndone = 0;
pos = 0;
while (PyDict_Next(modules, &pos, &key, &value)) {
if (value->ob_refcnt != 1)
continue;
if (PyString_Check(key) && PyModule_Check(value)) {
name = PyString_AS_STRING(key);
if (strcmp(name, "__builtin__") == 0)
continue;
if (strcmp(name, "sys") == 0)
continue;
if (Py_VerboseFlag)
PySys_WriteStderr(
"# cleanup[1] %s\n", name);
_PyModule_Clear(value);
PyDict_SetItem(modules, key, Py_None);
ndone++;
}
}
} while (ndone > 0);
/* Next, delete all modules (still skipping __builtin__ and sys) */
pos = 0;
while (PyDict_Next(modules, &pos, &key, &value)) {
if (PyString_Check(key) && PyModule_Check(value)) {
name = PyString_AS_STRING(key);
if (strcmp(name, "__builtin__") == 0)
continue;
if (strcmp(name, "sys") == 0)
continue;
if (Py_VerboseFlag)
PySys_WriteStderr("# cleanup[2] %s\n", name);
_PyModule_Clear(value);
PyDict_SetItem(modules, key, Py_None);
}
}
/* Next, delete sys and __builtin__ (in that order) */
value = PyDict_GetItemString(modules, "sys");
if (value != NULL && PyModule_Check(value)) {
if (Py_VerboseFlag)
PySys_WriteStderr("# cleanup sys\n");
_PyModule_Clear(value);
PyDict_SetItemString(modules, "sys", Py_None);
}
value = PyDict_GetItemString(modules, "__builtin__");
if (value != NULL && PyModule_Check(value)) {
if (Py_VerboseFlag)
PySys_WriteStderr("# cleanup __builtin__\n");
_PyModule_Clear(value);
PyDict_SetItemString(modules, "__builtin__", Py_None);
}
/* Finally, clear and delete the modules directory */
PyDict_Clear(modules);
interp->modules = NULL;
Py_DECREF(modules);
Py_CLEAR(interp->modules_reloading);
}
/* Helper for pythonrun.c -- return magic number */
long
PyImport_GetMagicNumber(void)
{
return pyc_magic;
}
/* Magic for extension modules (built-in as well as dynamically
loaded). To prevent initializing an extension module more than
once, we keep a static dictionary 'extensions' keyed by module name
(for built-in modules) or by filename (for dynamically loaded
modules), containing these modules. A copy of the module's
dictionary is stored by calling _PyImport_FixupExtension()
immediately after the module initialization function succeeds. A
copy can be retrieved from there by calling
_PyImport_FindExtension(). */
PyObject *
_PyImport_FixupExtension(char *name, char *filename)
{
PyObject *modules, *mod, *dict, *copy;
if (extensions == NULL) {
extensions = PyDict_New();
if (extensions == NULL)
return NULL;
}
modules = PyImport_GetModuleDict();
mod = PyDict_GetItemString(modules, name);
if (mod == NULL || !PyModule_Check(mod)) {
PyErr_Format(PyExc_SystemError,
"_PyImport_FixupExtension: module %.200s not loaded", name);
return NULL;
}
dict = PyModule_GetDict(mod);
if (dict == NULL)
return NULL;
copy = PyDict_Copy(dict);
if (copy == NULL)
return NULL;
PyDict_SetItemString(extensions, filename, copy);
Py_DECREF(copy);
return copy;
}
PyObject *
_PyImport_FindExtension(char *name, char *filename)
{
PyObject *dict, *mod, *mdict;
if (extensions == NULL)
return NULL;
dict = PyDict_GetItemString(extensions, filename);
if (dict == NULL)
return NULL;
mod = PyImport_AddModule(name);
if (mod == NULL)
return NULL;
mdict = PyModule_GetDict(mod);
if (mdict == NULL)
return NULL;
if (PyDict_Update(mdict, dict))
return NULL;
if (Py_VerboseFlag)
PySys_WriteStderr("import %s # previously loaded (%s)\n",
name, filename);
return mod;
}
/* Get the module object corresponding to a module name.
First check the modules dictionary if there's one there,
if not, create a new one and insert it in the modules dictionary.
Because the former action is most common, THIS DOES NOT RETURN A
'NEW' REFERENCE! */
PyObject *
PyImport_AddModule(const char *name)
{
PyObject *modules = PyImport_GetModuleDict();
PyObject *m;
if ((m = PyDict_GetItemString(modules, name)) != NULL &&
PyModule_Check(m))
return m;
m = PyModule_New(name);
if (m == NULL)
return NULL;
if (PyDict_SetItemString(modules, name, m) != 0) {
Py_DECREF(m);
return NULL;
}
Py_DECREF(m); /* Yes, it still exists, in modules! */
return m;
}
/* Remove name from sys.modules, if it's there. */
static void
_RemoveModule(const char *name)
{
PyObject *modules = PyImport_GetModuleDict();
if (PyDict_GetItemString(modules, name) == NULL)
return;
if (PyDict_DelItemString(modules, name) < 0)
Py_FatalError("import: deleting existing key in"
"sys.modules failed");
}
/* Execute a code object in a module and return the module object
* WITH INCREMENTED REFERENCE COUNT. If an error occurs, name is
* removed from sys.modules, to avoid leaving damaged module objects
* in sys.modules. The caller may wish to restore the original
* module object (if any) in this case; PyImport_ReloadModule is an
* example.
*/
PyObject *
PyImport_ExecCodeModule(char *name, PyObject *co)
{
return PyImport_ExecCodeModuleEx(name, co, (char *)NULL);
}
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;
/* If the module is being reloaded, we get the old module back
and re-use its dict to exec the new code. */
d = PyModule_GetDict(m);
if (PyDict_GetItemString(d, "__builtins__") == NULL) {
if (PyDict_SetItemString(d, "__builtins__",
PyEval_GetBuiltins()) != 0)
goto error;
}
/* 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)
goto error;
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;
error:
_RemoveModule(name);
return NULL;
}
/* 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_WINDOWS
/* 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, time_t 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);
if (co == NULL)
return NULL;
if (!PyCode_Check(co)) {
PyErr_Format(PyExc_ImportError,
"Non-code object in %.200s", cpathname);
Py_DECREF(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(const char *pathname, FILE *fp)
{
PyCodeObject *co = NULL;
mod_ty mod;
PyCompilerFlags flags;
PyArena *arena = PyArena_New();
if (arena == NULL)
return NULL;
flags.cf_flags = 0;
mod = PyParser_ASTFromFile(fp, pathname, Py_file_input, 0, 0, &flags,
NULL, arena);
if (mod) {
co = PyAST_Compile(mod, pathname, NULL, arena);
}
PyArena_Free(arena);
return co;
}
/* Helper to open a bytecode file for writing in exclusive mode */
static FILE *
open_exclusive(char *filename, mode_t mode)
{
#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
#ifdef __VMS
, mode, "ctxt=bin", "shr=nil"
#else
, mode
#endif
);
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, struct stat *srcstat)
{
FILE *fp;
time_t mtime = srcstat->st_mtime;
mode_t mode = srcstat->st_mode;
fp = open_exclusive(cpathname, mode);
if (fp == NULL) {
if (Py_VerboseFlag)
PySys_WriteStderr(
"# can't create %s\n", cpathname);
return;
}
PyMarshal_WriteLongToFile(pyc_magic, fp, Py_MARSHAL_VERSION);
/* First write a 0 for mtime */
PyMarshal_WriteLongToFile(0L, fp, Py_MARSHAL_VERSION);
PyMarshal_WriteObjectToFile((PyObject *)co, fp, Py_MARSHAL_VERSION);
if (fflush(fp) != 0 || ferror(fp)) {
if (Py_VerboseFlag)
PySys_WriteStderr("# can't write %s\n", cpathname);
/* Don't keep partial file */
fclose(fp);
(void) unlink(cpathname);
return;
}
/* Now write the true mtime */
fseek(fp, 4L, 0);
assert(mtime < LONG_MAX);
PyMarshal_WriteLongToFile((long)mtime, fp, Py_MARSHAL_VERSION);
fflush(fp);
fclose(fp);
if (Py_VerboseFlag)
PySys_WriteStderr("# wrote %s\n", cpathname);
}
static void
update_code_filenames(PyCodeObject *co, PyObject *oldname, PyObject *newname)
{
PyObject *constants, *tmp;
Py_ssize_t i, n;
if (!_PyString_Eq(co->co_filename, oldname))
return;
tmp = co->co_filename;
co->co_filename = newname;
Py_INCREF(co->co_filename);
Py_DECREF(tmp);
constants = co->co_consts;
n = PyTuple_GET_SIZE(constants);
for (i = 0; i < n; i++) {
tmp = PyTuple_GET_ITEM(constants, i);
if (PyCode_Check(tmp))
update_code_filenames((PyCodeObject *)tmp,
oldname, newname);
}
}
static int
update_compiled_module(PyCodeObject *co, char *pathname)
{
PyObject *oldname, *newname;
if (strcmp(PyString_AsString(co->co_filename), pathname) == 0)
return 0;
newname = PyString_FromString(pathname);
if (newname == NULL)
return -1;
oldname = co->co_filename;
Py_INCREF(oldname);
update_code_filenames(co, oldname, newname);
Py_DECREF(oldname);
Py_DECREF(newname);
return 1;
}
/* 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)
{
struct stat st;
FILE *fpc;
char buf[MAXPATHLEN+1];
char *cpathname;
PyCodeObject *co;
PyObject *m;
if (fstat(fileno(fp), &st) != 0) {
PyErr_Format(PyExc_RuntimeError,
"unable to get file status from '%s'",
pathname);
return NULL;
}
#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 (st.st_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, st.st_mtime, cpathname))) {
co = read_compiled_module(cpathname, fpc);
fclose(fpc);
if (co == NULL)
return NULL;
if (update_compiled_module(co, pathname) < 0)
return NULL;
if (Py_VerboseFlag)
PySys_WriteStderr("import %s # precompiled from %s\n",
name, cpathname);
pathname = cpathname;