mirror of
https://github.com/python/cpython.git
synced 2025-11-03 23:21:29 +00:00
2e5d8a90aa
This matches the GIL releasing behavior of our existing `_hashopenssl` module, extending it to the HACL* built-ins. Includes adding comments to better describe the ENTER/LEAVE macros purpose and explain the lock strategy in both existing and new code.
66 lines
2.5 KiB
C
66 lines
2.5 KiB
C
/* Common code for use by all hashlib related modules. */
|
|
|
|
/*
|
|
* Given a PyObject* obj, fill in the Py_buffer* viewp with the result
|
|
* of PyObject_GetBuffer. Sets an exception and issues the erraction
|
|
* on any errors, e.g. 'return NULL' or 'goto error'.
|
|
*/
|
|
#define GET_BUFFER_VIEW_OR_ERROR(obj, viewp, erraction) do { \
|
|
if (PyUnicode_Check((obj))) { \
|
|
PyErr_SetString(PyExc_TypeError, \
|
|
"Strings must be encoded before hashing");\
|
|
erraction; \
|
|
} \
|
|
if (!PyObject_CheckBuffer((obj))) { \
|
|
PyErr_SetString(PyExc_TypeError, \
|
|
"object supporting the buffer API required"); \
|
|
erraction; \
|
|
} \
|
|
if (PyObject_GetBuffer((obj), (viewp), PyBUF_SIMPLE) == -1) { \
|
|
erraction; \
|
|
} \
|
|
if ((viewp)->ndim > 1) { \
|
|
PyErr_SetString(PyExc_BufferError, \
|
|
"Buffer must be single dimension"); \
|
|
PyBuffer_Release((viewp)); \
|
|
erraction; \
|
|
} \
|
|
} while(0)
|
|
|
|
#define GET_BUFFER_VIEW_OR_ERROUT(obj, viewp) \
|
|
GET_BUFFER_VIEW_OR_ERROR(obj, viewp, return NULL)
|
|
|
|
/*
|
|
* Helper code to synchronize access to the hash object when the GIL is
|
|
* released around a CPU consuming hashlib operation. All code paths that
|
|
* access a mutable part of obj must be enclosed in an ENTER_HASHLIB /
|
|
* LEAVE_HASHLIB block or explicitly acquire and release the lock inside
|
|
* a PY_BEGIN / END_ALLOW_THREADS block if they wish to release the GIL for
|
|
* an operation.
|
|
*
|
|
* These only drop the GIL if the lock acquisition itself is likely to
|
|
* block. Thus the non-blocking acquire gating the GIL release for a
|
|
* blocking lock acquisition. The intent of these macros is to surround
|
|
* the assumed always "fast" operations that you aren't releasing the
|
|
* GIL around. Otherwise use code similar to what you see in hash
|
|
* function update() methods.
|
|
*/
|
|
|
|
#include "pythread.h"
|
|
#define ENTER_HASHLIB(obj) \
|
|
if ((obj)->lock) { \
|
|
if (!PyThread_acquire_lock((obj)->lock, 0)) { \
|
|
Py_BEGIN_ALLOW_THREADS \
|
|
PyThread_acquire_lock((obj)->lock, 1); \
|
|
Py_END_ALLOW_THREADS \
|
|
} \
|
|
}
|
|
#define LEAVE_HASHLIB(obj) \
|
|
if ((obj)->lock) { \
|
|
PyThread_release_lock((obj)->lock); \
|
|
}
|
|
|
|
/* TODO(gpshead): We should make this a module or class attribute
|
|
* to allow the user to optimize based on the platform they're using. */
|
|
#define HASHLIB_GIL_MINSIZE 2048
|
|
|