1 /* Common code for use by all hashlib related modules. */
2 
3 /*
4  * Given a PyObject* obj, fill in the Py_buffer* viewp with the result
5  * of PyObject_GetBuffer.  Sets an exception and issues the erraction
6  * on any errors, e.g. 'return NULL' or 'goto error'.
7  */
8 #define GET_BUFFER_VIEW_OR_ERROR(obj, viewp, erraction) do { \
9         if (PyUnicode_Check((obj))) { \
10             PyErr_SetString(PyExc_TypeError, \
11                             "Unicode-objects must be encoded before hashing");\
12             erraction; \
13         } \
14         if (!PyObject_CheckBuffer((obj))) { \
15             PyErr_SetString(PyExc_TypeError, \
16                             "object supporting the buffer API required"); \
17             erraction; \
18         } \
19         if (PyObject_GetBuffer((obj), (viewp), PyBUF_SIMPLE) == -1) { \
20             erraction; \
21         } \
22         if ((viewp)->ndim > 1) { \
23             PyErr_SetString(PyExc_BufferError, \
24                             "Buffer must be single dimension"); \
25             PyBuffer_Release((viewp)); \
26             erraction; \
27         } \
28     } while(0)
29 
30 #define GET_BUFFER_VIEW_OR_ERROUT(obj, viewp) \
31     GET_BUFFER_VIEW_OR_ERROR(obj, viewp, return NULL)
32 
33 /*
34  * Helper code to synchronize access to the hash object when the GIL is
35  * released around a CPU consuming hashlib operation. All code paths that
36  * access a mutable part of obj must be enclosed in an ENTER_HASHLIB /
37  * LEAVE_HASHLIB block or explicitly acquire and release the lock inside
38  * a PY_BEGIN / END_ALLOW_THREADS block if they wish to release the GIL for
39  * an operation.
40  */
41 
42 #ifdef WITH_THREAD
43 #include "pythread.h"
44     #define ENTER_HASHLIB(obj) \
45         if ((obj)->lock) { \
46             if (!PyThread_acquire_lock((obj)->lock, 0)) { \
47                 Py_BEGIN_ALLOW_THREADS \
48                 PyThread_acquire_lock((obj)->lock, 1); \
49                 Py_END_ALLOW_THREADS \
50             } \
51         }
52     #define LEAVE_HASHLIB(obj) \
53         if ((obj)->lock) { \
54             PyThread_release_lock((obj)->lock); \
55         }
56 #else
57     #define ENTER_HASHLIB(obj)
58     #define LEAVE_HASHLIB(obj)
59 #endif
60 
61 /* TODO(gps): We should probably make this a module or EVPobject attribute
62  * to allow the user to optimize based on the platform they're using. */
63 #define HASHLIB_GIL_MINSIZE 2048
64 
65