bpo-32030: Add _PyImport_Fini2() (#4737)

PyImport_ExtendInittab() now uses PyMem_RawRealloc() rather than
PyMem_Realloc(). PyImport_ExtendInittab() can be called before
Py_Initialize() whereas only the PyMem_Raw allocator is supposed to
be used before Py_Initialize().

Add _PyImport_Fini2() to release the memory allocated by
PyImport_ExtendInittab() at exit. PyImport_ExtendInittab() now forces
the usage of the default raw allocator, to be able to release memory
in _PyImport_Fini2().

Don't export these functions anymore to be C API, only to
Py_BUILD_CORE:

* _PyExc_Fini()
* _PyImport_Fini()
* _PyGC_DumpShutdownStats()
* _PyGC_Fini()
* _PyType_Fini()
* _Py_HashRandomization_Fini()
This commit is contained in:
Victor Stinner 2017-12-06 18:12:59 +01:00 committed by GitHub
parent 1b4587a246
commit 92a3c6f493
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 78 additions and 35 deletions

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@ -137,9 +137,18 @@ PyAPI_FUNC(_PyInitError) _Py_HashRandomization_Init(_PyCoreConfig *core_config);
#endif
/* Various internal finalizers */
#ifndef Py_LIMITED_API
#ifdef Py_BUILD_CORE
PyAPI_FUNC(void) _PyExc_Fini(void);
PyAPI_FUNC(void) _PyImport_Fini(void);
PyAPI_FUNC(void) _PyImport_Fini2(void);
PyAPI_FUNC(void) _PyGC_DumpShutdownStats(void);
PyAPI_FUNC(void) _PyGC_Fini(void);
PyAPI_FUNC(void) _PyType_Fini(void);
PyAPI_FUNC(void) _Py_HashRandomization_Fini(void);
#endif /* Py_BUILD_CORE */
#ifndef Py_LIMITED_API
PyAPI_FUNC(void) PyMethod_Fini(void);
PyAPI_FUNC(void) PyFrame_Fini(void);
PyAPI_FUNC(void) PyCFunction_Fini(void);
@ -151,15 +160,11 @@ PyAPI_FUNC(void) PyBytes_Fini(void);
PyAPI_FUNC(void) PyByteArray_Fini(void);
PyAPI_FUNC(void) PyFloat_Fini(void);
PyAPI_FUNC(void) PyOS_FiniInterrupts(void);
PyAPI_FUNC(void) _PyGC_DumpShutdownStats(void);
PyAPI_FUNC(void) _PyGC_Fini(void);
PyAPI_FUNC(void) PySlice_Fini(void);
PyAPI_FUNC(void) _PyType_Fini(void);
PyAPI_FUNC(void) _Py_HashRandomization_Fini(void);
PyAPI_FUNC(void) PyAsyncGen_Fini(void);
PyAPI_FUNC(int) _Py_IsFinalizing(void);
#endif
#endif /* !Py_LIMITED_API */
/* Signals */
typedef void (*PyOS_sighandler_t)(int);

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@ -446,17 +446,18 @@ pymain_optlist_clear(_Py_OptList *list)
list->options = NULL;
}
/* Free global variables which cannot be freed in Py_Finalize():
configuration options set before Py_Initialize() which should
remain valid after Py_Finalize(), since Py_Initialize()/Py_Finalize() can
be called multiple times.
Called with the current memory allocators. */
static void
pymain_free_impl(_PyMain *pymain)
pymain_free_globals(_PyMain *pymain)
{
_Py_CommandLineDetails *cmdline = &pymain->cmdline;
pymain_optlist_clear(&cmdline->warning_options);
pymain_optlist_clear(&cmdline->xoptions);
PyMem_RawFree(cmdline->command);
pymain_optlist_clear(&pymain->env_warning_options);
Py_CLEAR(pymain->main_importer_path);
_PyPathConfig_Clear(&_Py_path_config);
_PyImport_Fini2();
_PyMainInterpreterConfig_Clear(&pymain->config);
#ifdef __INSURE__
@ -473,6 +474,20 @@ pymain_free_impl(_PyMain *pymain)
#endif /* __INSURE__ */
}
static void
pymain_free_pymain(_PyMain *pymain)
{
_Py_CommandLineDetails *cmdline = &pymain->cmdline;
pymain_optlist_clear(&cmdline->warning_options);
pymain_optlist_clear(&cmdline->xoptions);
PyMem_RawFree(cmdline->command);
pymain_optlist_clear(&pymain->env_warning_options);
Py_CLEAR(pymain->main_importer_path);
}
static void
pymain_free(_PyMain *pymain)
{
@ -480,12 +495,12 @@ pymain_free(_PyMain *pymain)
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
pymain_free_impl(pymain);
pymain_free_pymain(pymain);
pymain_free_globals(pymain);
PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
}
static int
pymain_run_main_from_importer(_PyMain *pymain)
{
@ -1719,13 +1734,6 @@ pymain_impl(_PyMain *pymain)
pymain->status = 120;
}
/* _PyPathConfig_Clear() cannot be called in Py_FinalizeEx().
Py_Initialize() and Py_Finalize() can be called multiple times, but it
must not "forget" parameters set by Py_SetProgramName(), Py_SetPath() or
Py_SetPythonHome(), whereas _PyPathConfig_Clear() clear all these
parameters. */
_PyPathConfig_Clear(&_Py_path_config);
return 0;
}

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@ -30,6 +30,7 @@ static PyObject *extensions = NULL;
extern struct _inittab _PyImport_Inittab[];
struct _inittab *PyImport_Inittab = _PyImport_Inittab;
static struct _inittab *inittab_copy = NULL;
/*[clinic input]
module _imp
@ -285,6 +286,19 @@ _PyImport_Fini(void)
}
}
void
_PyImport_Fini2(void)
{
/* Use the same memory allocator than PyImport_ExtendInittab(). */
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
/* Free memory allocated by PyImport_ExtendInittab() */
PyMem_RawFree(inittab_copy);
PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
}
/* Helper for sys */
PyObject *
@ -2233,9 +2247,9 @@ PyInit_imp(void)
int
PyImport_ExtendInittab(struct _inittab *newtab)
{
static struct _inittab *our_copy = NULL;
struct _inittab *p;
int i, n;
Py_ssize_t i, n;
int res = 0;
/* Count the number of entries in both tables */
for (n = 0; newtab[n].name != NULL; n++)
@ -2245,19 +2259,35 @@ PyImport_ExtendInittab(struct _inittab *newtab)
for (i = 0; PyImport_Inittab[i].name != NULL; i++)
;
/* Force default raw memory allocator to get a known allocator to be able
to release the memory in _PyImport_Fini2() */
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
/* Allocate new memory for the combined table */
p = our_copy;
PyMem_RESIZE(p, struct _inittab, i+n+1);
if (p == NULL)
return -1;
if ((i + n + 1) <= PY_SSIZE_T_MAX / sizeof(struct _inittab)) {
size_t size = sizeof(struct _inittab) * (i + n + 1);
p = PyMem_RawRealloc(inittab_copy, size);
}
else {
p = NULL;
}
if (p == NULL) {
res = -1;
goto done;
}
/* Copy the tables into the new memory */
if (our_copy != PyImport_Inittab)
/* Copy the tables into the new memory at the first call
to PyImport_ExtendInittab(). */
if (inittab_copy != PyImport_Inittab) {
memcpy(p, PyImport_Inittab, (i+1) * sizeof(struct _inittab));
PyImport_Inittab = our_copy = p;
memcpy(p+i, newtab, (n+1) * sizeof(struct _inittab));
}
memcpy(p + i, newtab, (n + 1) * sizeof(struct _inittab));
PyImport_Inittab = inittab_copy = p;
return 0;
done:
PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
return res;
}
/* Shorthand to add a single entry given a name and a function */