Only define PyObject_GetBuffer etc. if really needed

Cython/Compiler/ModuleNode.py

@@ -260,7 +260,6 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         self.generate_module_cleanup_func(env, code)
         self.generate_filename_table(code)
         self.generate_utility_functions(env, code)
-        self.generate_buffer_compatability_functions(env, code)
 
         self.generate_declarations_for_modules(env, modules, code.h)
 
@@ -441,8 +440,6 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         code.putln("  #define PyBUF_ANY_CONTIGUOUS (0x0080 | PyBUF_STRIDES)")
         code.putln("  #define PyBUF_INDIRECT (0x0100 | PyBUF_STRIDES)")
         code.putln("")
-        code.putln("  static int PyObject_GetBuffer(PyObject *obj, Py_buffer *view, int flags);")
-        code.putln("  static void PyObject_ReleaseBuffer(PyObject *obj, Py_buffer *view);")
         code.putln("#endif")
 
         code.put(builtin_module_name_utility_code[0])
@@ -1956,106 +1953,6 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         code.put(PyrexTypes.type_conversion_functions)
         code.putln("")
 
-    def generate_buffer_compatability_functions(self, env, code):
-        # will be refactored
-        try:
-            env.entries[u'numpy']
-            code.put("""
-static int numpy_getbuffer(PyObject *obj, Py_buffer *view, int flags) {
-  /* This function is always called after a type-check; safe to cast */
-  PyArrayObject *arr = (PyArrayObject*)obj;
-  PyArray_Descr *type = (PyArray_Descr*)arr->descr;
-
-  
-  int typenum = PyArray_TYPE(obj);
-  if (!PyTypeNum_ISNUMBER(typenum)) {
-    PyErr_Format(PyExc_TypeError, "Only numeric NumPy types currently supported.");
-    return -1;
-  }
-
-  /*
-  NumPy format codes doesn't completely match buffer codes;
-  seems safest to retranslate.
-                            01234567890123456789012345*/
-  const char* base_codes = "?bBhHiIlLqQfdgfdgO";
-
-  char* format = (char*)malloc(4);
-  char* fp = format;
-  *fp++ = type->byteorder;
-  if (PyTypeNum_ISCOMPLEX(typenum)) *fp++ = 'Z';
-  *fp++ = base_codes[typenum];
-  *fp = 0;
-
-  view->buf = arr->data;
-  view->readonly = !PyArray_ISWRITEABLE(obj);
-  view->ndim = PyArray_NDIM(arr);
-  view->strides = PyArray_STRIDES(arr);
-  view->shape = PyArray_DIMS(arr);
-  view->suboffsets = NULL;
-  view->format = format;
-  view->itemsize = type->elsize;
-
-  view->internal = 0;
-  return 0;
-}
-
-static void numpy_releasebuffer(PyObject *obj, Py_buffer *view) {
-  free((char*)view->format);
-  view->format = NULL;
-}
-
-""")
-        except KeyError:
-            pass
-
-        # Search all types for __getbuffer__ overloads
-        types = []
-        def find_buffer_types(scope):
-            for m in scope.cimported_modules:
-                find_buffer_types(m)
-            for e in scope.type_entries:
-                t = e.type
-                if t.is_extension_type:
-                    release = get = None
-                    for x in t.scope.pyfunc_entries:
-                        if x.name == u"__getbuffer__": get = x.func_cname
-                        elif x.name == u"__releasebuffer__": release = x.func_cname
-                    if get:
-                        types.append((t.typeptr_cname, get, release))
-                                     
-        find_buffer_types(self.scope)
-        
-        # For now, hard-code numpy imported as "numpy"
-        try:
-            ndarrtype = env.entries[u'numpy'].as_module.entries['ndarray'].type
-            types.append((ndarrtype.typeptr_cname, "numpy_getbuffer", "numpy_releasebuffer"))
-        except KeyError:
-            pass
-        code.putln("#if PY_VERSION_HEX < 0x02060000")
-        code.putln("static int PyObject_GetBuffer(PyObject *obj, Py_buffer *view, int flags) {")
-        if len(types) > 0:
-            clause = "if"
-            for t, get, release in types:
-                code.putln("%s (PyObject_TypeCheck(obj, %s)) return %s(obj, view, flags);" % (clause, t, get))
-                clause = "else if"
-            code.putln("else {")
-        code.putln("PyErr_Format(PyExc_TypeError, \"'%100s' does not have the buffer interface\", Py_TYPE(obj)->tp_name);")
-        code.putln("return -1;")
-        if len(types) > 0: code.putln("}")
-        code.putln("}")
-        code.putln("")
-        code.putln("static void PyObject_ReleaseBuffer(PyObject *obj, Py_buffer *view) {")
-        if len(types) > 0:
-            clause = "if"
-            for t, get, release in types:
-                if release:
-                    code.putln("%s (PyObject_TypeCheck(obj, %s)) %s(obj, view);" % (clause, t, release))
-                    clause = "else if"
-        code.putln("}")
-        code.putln("")
-        code.putln("#endif")
-
-
 #------------------------------------------------------------------------------------
 #
 #  Runtime support code

Cython/Compiler/Symtab.py

@@ -15,6 +15,7 @@ from TypeSlots import \
     get_special_method_signature, get_property_accessor_signature
 import ControlFlow
 import __builtin__
+from sets import Set as set
 
 possible_identifier = re.compile(ur"(?![0-9])\w+$", re.U).match
 nice_identifier = re.compile('^[a-zA-Z0-0_]+$').match
@@ -626,9 +627,12 @@ class Scope:
         return [entry for entry in self.temp_entries
             if entry not in self.free_temp_entries]
     
-    def use_utility_code(self, new_code):
-        self.global_scope().use_utility_code(new_code)
+    def use_utility_code(self, new_code, name=None):
+        self.global_scope().use_utility_code(new_code, name)
     
+    def has_utility_code(self, name):
+        return self.global_scope().has_utility_code(name)
+
     def generate_library_function_declarations(self, code):
         # Generate extern decls for C library funcs used.
         #if self.pow_function_used:
@@ -748,6 +752,7 @@ class ModuleScope(Scope):
     # doc_cname            string             C name of module doc string
     # const_counter        integer            Counter for naming constants
     # utility_code_used    [string]           Utility code to be included
+    # utility_code_names   set(string)        (Optional) names for named (often generated) utility code
     # default_entries      [Entry]            Function argument default entries
     # python_include_files [string]           Standard  Python headers to be included
     # include_files        [string]           Other C headers to be included
@@ -782,6 +787,7 @@ class ModuleScope(Scope):
         self.doc_cname = Naming.moddoc_cname
         self.const_counter = 1
         self.utility_code_used = []
+        self.utility_code_names = set()
         self.default_entries = []
         self.module_entries = {}
         self.python_include_files = ["Python.h", "structmember.h"]
@@ -940,13 +946,25 @@ class ModuleScope(Scope):
         self.const_counter = n + 1
         return "%s%s%d" % (Naming.const_prefix, prefix, n)
     
-    def use_utility_code(self, new_code):
+    def use_utility_code(self, new_code, name=None):
         #  Add string to list of utility code to be included,
-        #  if not already there (tested using 'is').
+        #  if not already there (tested using the provided name,
+        #  or 'is' if name=None -- if the utility code is dynamically
+        #  generated, use the name, otherwise it is not needed).
+        if name is not None:
+            if name in self.utility_code_names:
+                return
         for old_code in self.utility_code_used:
             if old_code is new_code:
                 return
         self.utility_code_used.append(new_code)
+        self.utility_code_names.add(name)
+
+    def has_utility_code(self, name):
+        # Checks if utility code (that is registered by name) has
+        # previously been registered. This is useful if the utility code
+        # is dynamically generated to avoid re-generation.
+        return name in self.utility_code_names
     
     def declare_c_class(self, name, pos, defining = 0, implementing = 0,
         module_name = None, base_type = None, objstruct_cname = None,