[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [33462] trunk/blender/source/blender/ python/intern/bpy_rna.c: disallow setting RNA attributes while drawing, this is bad practice so enforcing here has the benifit of making sure people are not manipulating blender scene data in a drawing panel for eg .

[Campbell Barton]

Revision: 33462
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=33462
Author:   campbellbarton
Date:     2010-12-04 07:25:36 +0100 (Sat, 04 Dec 2010)

Log Message:
-----------
disallow setting RNA attributes while drawing, this is bad practice so enforcing here has the benifit of making sure people are not manipulating blender scene data in a drawing panel for eg.

This is ifdef'd and may be disabled later on, or only enabled in debug mode.

This applies to setting any RNA value that has an ID and is not a screen or window-manager datablock.

Some addons break this rule and need fixing but from my tests blender UI scripts are ok.

Modified Paths:
--------------
    trunk/blender/source/blender/python/intern/bpy_rna.c

Modified: trunk/blender/source/blender/python/intern/bpy_rna.c
===================================================================
--- trunk/blender/source/blender/python/intern/bpy_rna.c	2010-12-04 06:21:08 UTC (rev 33461)
+++ trunk/blender/source/blender/python/intern/bpy_rna.c	2010-12-04 06:25:36 UTC (rev 33462)
@@ -50,6 +50,7 @@
 #include "DNA_anim_types.h"
 #include "ED_keyframing.h"
 
+#define USE_PEDANTIC_WRITE
 #define USE_MATHUTILS
 #define USE_STRING_COERCE
 
@@ -67,7 +68,32 @@
 
 /* bpyrna vector/euler/quat callbacks */
 static int mathutils_rna_array_cb_index= -1; /* index for our callbacks */
+#ifdef USE_PEDANTIC_WRITE
+static short rna_disallow_writes= FALSE;
 
+static int rna_id_write_error(PointerRNA *ptr, PyObject *key)
+{
+	ID *id= ptr->id.data;
+	if(id) {
+		const short idcode= GS(id->name);
+		if(!ELEM(idcode, ID_WM, ID_SCR)) { /* may need more added here */
+			const char *idtype= BKE_idcode_to_name(idcode);
+			const char *pyname;
+			if(key && PyUnicode_Check(key))	pyname= _PyUnicode_AsString(key);
+			else							pyname= "<UNKNOWN>";
+	
+			/* make a nice string error */
+			assert(idtype != NULL);
+			PyErr_Format(PyExc_RuntimeError, "Writing to ID classes in this context is not allowed: %.200s, %.200s datablock, error setting %.200s.%.200s", id->name+2, idtype, RNA_struct_identifier(ptr->type), pyname);
+	
+			return TRUE;
+		}
+	}
+	return FALSE;
+}
+
+#endif
+
 /* subtype not used much yet */
 #define MATHUTILS_CB_SUBTYPE_EUL 0
 #define MATHUTILS_CB_SUBTYPE_VEC 1
@@ -104,7 +130,13 @@
 	float min, max;
 	if(self->prop==NULL)
 		return 0;
-	
+
+#ifdef USE_PEDANTIC_WRITE
+	if(rna_disallow_writes && rna_id_write_error(&self->ptr, NULL)) {
+		return 0;
+	}
+#endif
+
 	if (!RNA_property_editable_flag(&self->ptr, self->prop)) {
 		PyErr_Format(PyExc_AttributeError, "bpy_prop \"%.200s.%.200s\" is read-only", RNA_struct_identifier(self->ptr.type), RNA_property_identifier(self->prop));
 		return 0;
@@ -157,6 +189,12 @@
 	if(self->prop==NULL)
 		return 0;
 	
+#ifdef USE_PEDANTIC_WRITE
+	if(rna_disallow_writes && rna_id_write_error(&self->ptr, NULL)) {
+		return 0;
+	}
+#endif
+	
 	if (!RNA_property_editable_flag(&self->ptr, self->prop)) {
 		PyErr_Format(PyExc_AttributeError, "bpy_prop \"%.200s.%.200s\" is read-only", RNA_struct_identifier(self->ptr.type), RNA_property_identifier(self->prop));
 		return 0;
@@ -201,7 +239,13 @@
 	
 	if(self->prop==NULL)
 		return 0;
-	
+
+#ifdef USE_PEDANTIC_WRITE
+	if(rna_disallow_writes && rna_id_write_error(&self->ptr, NULL)) {
+		return 0;
+	}
+#endif
+
 	if (!RNA_property_editable_flag(&self->ptr, self->prop)) {
 		PyErr_Format(PyExc_AttributeError, "bpy_prop \"%.200s.%.200s\" is read-only", RNA_struct_identifier(self->ptr.type), RNA_property_identifier(self->prop));
 		return 0;
@@ -1903,6 +1947,12 @@
 {
 	IDProperty *group= RNA_struct_idprops(&self->ptr, 1);
 
+#ifdef USE_PEDANTIC_WRITE
+	if(rna_disallow_writes && rna_id_write_error(&self->ptr, key)) {
+		return -1;
+	}
+#endif
+
 	if(group==NULL) {
 		PyErr_SetString(PyExc_TypeError, "bpy_struct[key] = val: id properties not supported for this type");
 		return -1;
@@ -2727,6 +2777,12 @@
 	char *name = _PyUnicode_AsString(pyname);
 	PropertyRNA *prop= NULL;
 
+#ifdef USE_PEDANTIC_WRITE
+	if(rna_disallow_writes && rna_id_write_error(&self->ptr, pyname)) {
+		return -1;
+	}
+#endif
+
 	if(name == NULL) {
 		PyErr_SetString(PyExc_AttributeError, "bpy_struct: __setattr__ must be a string");
 		return -1;
@@ -2840,6 +2896,12 @@
 	PropertyRNA *prop;
 	PointerRNA r_ptr;
 
+#ifdef USE_PEDANTIC_WRITE
+	if(rna_disallow_writes && rna_id_write_error(&self->ptr, pyname)) {
+		return -1;
+	}
+#endif
+
 	if(name == NULL) {
 		PyErr_SetString(PyExc_AttributeError, "bpy_prop: __setattr__ must be a string");
 		return -1;
@@ -5080,7 +5142,11 @@
 	PyGILState_STATE gilstate;
 
 	bContext *C= BPy_GetContext(); // XXX - NEEDS FIXING, QUITE BAD.
-	
+#ifdef USE_PEDANTIC_WRITE
+	/* testing, for correctness, not operator and not draw function */
+	const short is_readonly= strstr("draw", RNA_function_identifier(func)) || !RNA_struct_is_a(ptr->type, &RNA_Operator);
+#endif
+
 	py_class= RNA_struct_py_type_get(ptr->type);
 	
 	/* rare case. can happen when registering subclasses */
@@ -5177,8 +5243,19 @@
 				i++;
 			}
 
+#ifdef USE_PEDANTIC_WRITE
+			rna_disallow_writes= is_readonly ? TRUE:FALSE;	
+#endif
+			/* *** Main Caller *** */
+			
 			ret = PyObject_Call(item, args, NULL);
 
+			/* *** Done Calling *** */
+
+#ifdef USE_PEDANTIC_WRITE
+			rna_disallow_writes= FALSE;
+#endif
+
 			RNA_parameter_list_end(&iter);
 			Py_DECREF(item);
 			Py_DECREF(args);