Skip to main content

Browse the archive

Staging
v0.8.1
Revision 55e0836849c14fb474e1ba7f37851e07660eea3c authored by Pablo Galindo on 15 September 2020, 18:32:56 UTC, committed by GitHub on 15 September 2020, 18:32:56 UTC 
[3.9] bpo-41631: _ast module uses again a global state (GH-21961) (GH-22258)
 
Partially revert commit ac46eb4ad6662cf6d771b20d8963658b2186c48c:
"bpo-38113: Update the Python-ast.c generator to PEP384 (gh-15957)".

Using a module state per module instance is causing subtle practical
problems.

For example, the Mercurial project replaces the __import__() function
to implement lazy import, whereas Python expected that "import _ast"
always return a fully initialized _ast module.

Add _PyAST_Fini() to clear the state at exit.

The _ast module has no state (set _astmodule.m_size to 0). Remove
astmodule_traverse(), astmodule_clear() and astmodule_free()
functions..
(cherry picked from commit e5fbe0cbd4be99ced5f000ad382208ad2a561c90)

Co-authored-by: Victor Stinner <vstinner@python.org>
1 parent 0cc037f
Raw File
hashlib.h 
/* 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, \
                            "Unicode-objects 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.
 */

#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(gps): We should probably make this a module or EVPobject attribute
 * to allow the user to optimize based on the platform they're using. */
#define HASHLIB_GIL_MINSIZE 2048
back to top