Remove locking from buffer protocol as-per discussion.

Include/object.h

@@ -163,7 +163,6 @@ typedef void (*releasebufferproc)(PyObject *, Py_buffer *);
 #define PyBUF_WRITABLE 0x0001
 /*  we used to include an E, backwards compatible alias  */
 #define PyBUF_WRITEABLE PyBUF_WRITABLE
-#define PyBUF_LOCK 0x0002
 #define PyBUF_FORMAT 0x0004
 #define PyBUF_ND 0x0008
 #define PyBUF_STRIDES (0x0010 | PyBUF_ND)
@@ -174,25 +173,15 @@ typedef void (*releasebufferproc)(PyObject *, Py_buffer *);
 
 #define PyBUF_CONTIG (PyBUF_ND | PyBUF_WRITABLE)
 #define PyBUF_CONTIG_RO (PyBUF_ND)
-#define PyBUF_CONTIG_LCK (PyBUF_ND | PyBUF_LOCK)
-#define PyBUF_CONTIG_XLCK (PyBUF_ND | PyBUF_LOCK | PyBUF_WRITABLE)
 
 #define PyBUF_STRIDED (PyBUF_STRIDES | PyBUF_WRITABLE)
 #define PyBUF_STRIDED_RO (PyBUF_STRIDES)
-#define PyBUF_STRIDED_LCK (PyBUF_STRIDES | PyBUF_LOCK)
-#define PyBUF_STRIDED_XLCK (PyBUF_STRIDES | PyBUF_LOCK | PyBUF_WRITABLE)
 
 #define PyBUF_RECORDS (PyBUF_STRIDES | PyBUF_WRITABLE | PyBUF_FORMAT)
 #define PyBUF_RECORDS_RO (PyBUF_STRIDES | PyBUF_FORMAT)
-#define PyBUF_RECORDS_LCK (PyBUF_STRIDES | PyBUF_LOCK | PyBUF_FORMAT)
-#define PyBUF_RECORDS_XLCK (PyBUF_STRIDES | PyBUF_LOCK | PyBUF_WRITABLE \
-			    | PyBUF_FORMAT)
 
 #define PyBUF_FULL (PyBUF_INDIRECT | PyBUF_WRITABLE | PyBUF_FORMAT)
 #define PyBUF_FULL_RO (PyBUF_INDIRECT | PyBUF_FORMAT)
-#define PyBUF_FULL_LCK (PyBUF_INDIRECT | PyBUF_LOCK | PyBUF_FORMAT)
-#define PyBUF_FULL_XLCK (PyBUF_INDIRECT | PyBUF_LOCK | PyBUF_WRITABLE \
-			 | PyBUF_FORMAT)
 
 
 #define PyBUF_READ  0x100

Modules/_bsddb.c

@@ -312,12 +312,6 @@ static Py_buffer * _malloc_view(PyObject *obj)
                         "Py_buffer malloc failed");
         return NULL;
     }
-    /* We use PyBUF_LOCK to prevent other threads from trashing the data
-       buffer while we release the GIL.  http://bugs.python.org/issue1035 */
-    if (PyObject_GetBuffer(obj, view, PyBUF_LOCK) == -1) {
-        PyMem_Free(view);
-        return NULL;
-    }
     if (view->ndim > 1) {
         PyErr_SetString(PyExc_BufferError,
                         "buffers must be single dimension");

Modules/_ctypes/_ctypes.c

@@ -2449,11 +2449,6 @@ static int CData_GetBuffer(PyObject *_self, Py_buffer *view, int flags)
 	Py_ssize_t i;
 
 	if (view == NULL) return 0;
-	if (((flags & PyBUF_LOCK) == PyBUF_LOCK)) {
-		PyErr_SetString(PyExc_BufferError,
-				"Cannot lock this object.");
-		return -1;
-	}
 
 	view->buf = self->b_ptr;
 	view->len = self->b_size;

Modules/arraymodule.c

@@ -1779,11 +1779,6 @@ static const void *emptybuf = "";
 static int
 array_buffer_getbuf(arrayobject *self, Py_buffer *view, int flags)
 {
-        if ((flags & PyBUF_LOCK)) {
-                PyErr_SetString(PyExc_BufferError,
-                                "Cannot lock data");
-                return -1;
-        }
         if (view==NULL) goto finish;
 
         view->buf = (void *)self->ob_item;

Objects/abstract.c

@@ -672,12 +672,6 @@ PyBuffer_FillInfo(Py_buffer *view, void *buf, Py_ssize_t len,
 	      int readonly, int flags)
 {
 	if (view == NULL) return 0;
-	if (((flags & PyBUF_LOCK) == PyBUF_LOCK) &&
-	    readonly != 0) {
-		PyErr_SetString(PyExc_BufferError,
-				"Cannot lock this object.");
-		return -1;
-	}
 	if (((flags & PyBUF_WRITABLE) == PyBUF_WRITABLE) &&
 	    (readonly == 1)) {
 		PyErr_SetString(PyExc_BufferError,

Objects/memoryobject.c

@@ -230,9 +230,6 @@ PyMemoryView_GetContiguous(PyObject *obj, int buffertype, char fort)
         case PyBUF_WRITE:
                 flags = PyBUF_FULL;
                 break;
-        case PyBUF_SHADOW:
-                flags = PyBUF_FULL_XLCK;
-                break;
         }
 
         if (PyObject_GetBuffer(obj, view, flags) != 0) {