First steps towards a generalized converter of Python object

hierarchies to CoreFoundation object hierarchies and vice versa.

Mac/Modules/cf/pycfbridge.c

+/*
+** Convert objects from Python to CoreFoundation and vice-versa.
+*/
+
+#ifdef WITHOUT_FRAMEWORKS
+#include <CFBase.h>
+#include <CFArray.h>
+#include <CFData.h>
+#include <CFDictionary.h>
+#include <CFString.h>
+#include <CFURL.h>
+#else
+#include <CoreServices/CoreServices.h>
+#endif
+
+#include "Python.h"
+#include "macglue.h"
+#include "pycfbridge.h"
+
+
+/* ---------------------------------------- */
+/* CoreFoundation objects to Python objects */
+/* ---------------------------------------- */
+
+PyObject *
+PyCF_CF2Python(CFTypeRef src) {
+	CFTypeID typeid;
+	
+	typeid = CFGetTypeID(src);
+	if (typeid == CFArrayGetTypeID())
+		return PyCF_CF2Python_sequence((CFArrayRef)src);
+	if (typeid == CFDictionaryGetTypeID())
+		return PyCF_CF2Python_mapping((CFDictionaryRef)src);
+	return PyCF_CF2Python_simple(src);
+}
+
+PyObject *
+PyCF_CF2Python_sequence(CFArrayRef src) {
+	PyErr_SetString(PyExc_SystemError, "Not yet implemented");
+	return NULL;
+}
+
+PyObject *
+PyCF_CF2Python_mapping(CFTypeRef src) {
+	PyErr_SetString(PyExc_SystemError, "Not yet implemented");
+	return NULL;
+}
+
+PyObject *
+PyCF_CF2Python_simple(CFTypeRef src) {
+	CFTypeID typeid;
+	
+	typeid = CFGetTypeID(src);
+	if (typeid == CFStringGetTypeID())
+		return PyCF_CF2Python_string((CFStringRef)src);
+	PyMac_Error(resNotFound);
+	return NULL;
+}
+
+/* Unsure - Return unicode or 8 bit strings? */
+PyObject *
+PyCF_CF2Python_string(CFStringRef src) {
+	int size = CFStringGetLength(src)+1;
+	Py_UNICODE *data = malloc(size*sizeof(Py_UNICODE));
+	CFRange range;
+	PyObject *rv;
+
+	range.location = 0;
+	range.length = size;
+	if( data == NULL ) return PyErr_NoMemory();
+	CFStringGetCharacters(src, range, data);
+	rv = (PyObject *)PyUnicode_FromUnicode(data, size);
+	free(data);
+	return rv;
+}
+
+/* ---------------------------------------- */
+/* Python objects to CoreFoundation objects */
+/* ---------------------------------------- */
+
+int
+PyCF_Python2CF(PyObject *src, CFTypeRef *dst) {
+
+	if (PySequence_Check(src))
+		return PyCF_Python2CF_sequence(src, (CFArrayRef *)dst);
+	if (PyMapping_Check(src))
+		return PyCF_Python2CF_mapping(src, (CFDictionaryRef *)dst);
+	return PyCF_Python2CF_simple(src, dst);
+}
+
+int
+PyCF_Python2CF_sequence(PyObject *src, CFArrayRef *dst) {
+	CFArrayRef rv = NULL;
+	CFTypeRef item_cf = NULL;
+	PyObject *item_py = NULL;
+	int size, i;
+	
+	size = PySequence_Size(src);
+	rv = CFArrayCreateMutable((CFAllocatorRef)NULL, size, &kCFTypeArrayCallBacks);
+	if (rv == NULL) {
+		PyMac_Error(resNotFound); 
+		goto err;
+	}
+
+	for( i=0; i<size; i++) {
+		item_py = PySequence_GetItem(src, i);
+		if (item_py == NULL) goto err;
+		if ( !PyCF_Python2CF(item_py, &item_cf)) goto err;
+		Py_DECREF(item_py);
+		CFArraySetValueAtIndex(rv, i, item_cf);
+		CFRelease(item_cf);
+		item_cf = NULL;
+	}
+	*dst = rv;
+	return 1;
+err:
+	Py_XDECREF(item_py);
+	if (rv) CFRelease(rv);
+	if (item_cf) CFRelease(item_cf);
+	return 0;		
+}
+
+int
+PyCF_Python2CF_mapping(PyObject *src, CFDictionaryRef *dst) {
+	CFDictionaryRef rv = NULL;
+	PyObject *aslist = NULL;
+	CFTypeRef key_cf = NULL, value_cf = NULL;
+	PyObject *item_py = NULL, *key_py = NULL, *value_py = NULL;
+	int size, i;
+	
+	size = PyMapping_Size(src);
+	rv = CFDictionaryCreateMutable((CFAllocatorRef)NULL, size,
+									&kCFTypeDictionaryKeyCallBacks,
+	                                &kCFTypeDictionaryValueCallBacks);
+	if (rv == NULL) {
+		PyMac_Error(resNotFound); 
+		goto err;
+	}
+	if ( (aslist = PyMapping_Items(src)) == NULL ) goto err;
+
+	for( i=0; i<size; i++) {
+		item_py = PySequence_GetItem(aslist, i);
+		if (item_py == NULL) goto err;
+		if (!PyArg_ParseTuple(item_py, "OO", key_py, value_py)) goto err;
+		if ( !PyCF_Python2CF(key_py, &key_cf) ) goto err;
+		Py_DECREF(key_py);
+		if ( !PyCF_Python2CF(value_cf, &key_cf) ) goto err;
+		Py_DECREF(value_py);
+		CFDictionaryAddValue(rv, key_cf, value_cf);
+		CFRelease(key_cf);
+		key_cf = NULL;
+		CFRelease(value_cf);
+		value_cf = NULL;
+	}
+	*dst = rv;
+	return 1;
+err:
+	Py_XDECREF(item_py);
+	Py_XDECREF(key_py);
+	Py_XDECREF(value_py);
+	Py_XDECREF(aslist);
+	if (rv) CFRelease(rv);
+	if (key_cf) CFRelease(key_cf);
+	if (value_cf) CFRelease(value_cf);
+	return 0;		
+}
+
+int
+PyCF_Python2CF_simple(PyObject *src, CFTypeRef *dst) {
+	
+	if (PyObject_HasAttrString(src, "CFType")) {
+		*dst = PyObject_CallMethod(src, "CFType", "");
+		return (*dst != NULL);
+	}
+	if (PyString_Check(src) || PyUnicode_Check(src)) 
+		return PyCF_Python2CF_string(src, (CFStringRef *)dst);
+	PyErr_Format(PyExc_TypeError,
+		  "Cannot convert %.500s objects to CF",
+				     src->ob_type->tp_name);
+	return 0;
+}
+
+int
+PyCF_Python2CF_string(PyObject *src, CFStringRef *dst) {
+	char *chars;
+	CFIndex size;
+	UniChar *unichars;
+	
+	if (PyString_Check(src)) {
+		if ((chars = PyString_AsString(src)) == NULL ) goto err;
+		*dst = CFStringCreateWithCString((CFAllocatorRef)NULL, chars, 0);
+		return 1;
+	}
+	if (PyUnicode_Check(src)) {
+		/* We use the CF types here, if Python was configured differently that will give an error */
+		size = PyUnicode_GetSize(src);
+		if ((unichars = PyUnicode_AsUnicode(src)) == NULL ) goto err;
+		*dst = CFStringCreateWithCharacters((CFAllocatorRef)NULL, unichars, size);
+		return 1;
+	}
+err:
+	PyErr_Format(PyExc_TypeError,
+		  "Cannot convert %.500s objects to CF",
+				     src->ob_type->tp_name);
+	return 0;
+}

Mac/Modules/cf/pycfbridge.h

+extern PyObject *PyCF_CF2Python(CFTypeRef src);
+extern PyObject *PyCF_CF2Python_sequence(CFArrayRef src);
+extern PyObject *PyCF_CF2Python_mapping(CFTypeRef src);
+extern PyObject *PyCF_CF2Python_simple(CFTypeRef src);
+extern PyObject *PyCF_CF2Python_string(CFStringRef src);
+
+extern int PyCF_Python2CF(PyObject *src, CFTypeRef *dst);
+extern int PyCF_Python2CF_sequence(PyObject *src, CFArrayRef *dst);
+extern int PyCF_Python2CF_mapping(PyObject *src, CFDictionaryRef *dst);
+extern int PyCF_Python2CF_simple(PyObject *src, CFTypeRef *dst);
+extern int PyCF_Python2CF_string(PyObject *src, CFStringRef *dst);
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