Fix segfault with bad setting in the Image node.

The limit in the UI tooltips to set the amount of
images used in animation allow the zero value,
that cause a segfault.

This commit fix the UI, add a init value of 1 to
the node and also check in case that
node_composit_get_image return NULL.

1 files changed, 22 insertions, 19 deletions

diff --git a/source/blender/nodes/intern/CMP_nodes/CMP_image.c b/source/blender/nodes/intern/CMP_nodes/CMP_image.c
index 6a82e8a9254..be5a1d7241b 100644
--- a/source/blender/nodes/intern/CMP_nodes/CMP_image.c
+++ b/source/blender/nodes/intern/CMP_nodes/CMP_image.c
@@ -201,31 +201,33 @@ static void node_composit_exec_image(void *data, bNode *node, bNodeStack **in, b
 		}
 		else {
 			stackbuf= node_composit_get_image(rd, ima, iuser);
+
+			if (stackbuf) {
+				/*respect image premul option*/
+				if (stackbuf->type==CB_RGBA && ima->flag & IMA_DO_PREMUL) {
+					int i;
+					float *pixel;
 			
-			/*respect image premul option*/
-			if (stackbuf->type==CB_RGBA && ima->flag & IMA_DO_PREMUL) {
-				int i;
-				float *pixel;
-			
-				/*first duplicate stackbuf->rect, since it's just a pointer
-				  to the source imbuf, and we don't want to change that.*/
-				stackbuf->rect = MEM_dupallocN(stackbuf->rect);
+					/*first duplicate stackbuf->rect, since it's just a pointer
+					  to the source imbuf, and we don't want to change that.*/
+					stackbuf->rect = MEM_dupallocN(stackbuf->rect);
 				
-				/*premul the image*/
+					/*premul the image*/
 				
-				pixel = stackbuf->rect;
-				for (i=0; i<stackbuf->x*stackbuf->y; i++, pixel += 4) {
-					pixel[0] *= pixel[3];
-					pixel[1] *= pixel[3];
-					pixel[2] *= pixel[3];
+					pixel = stackbuf->rect;
+					for (i=0; i<stackbuf->x*stackbuf->y; i++, pixel += 4) {
+						pixel[0] *= pixel[3];
+						pixel[1] *= pixel[3];
+						pixel[2] *= pixel[3];
+					}
 				}
-			}
 			
-			/* put image on stack */	
-			out[0]->data= stackbuf;
+				/* put image on stack */	
+				out[0]->data= stackbuf;
 			
-			if(out[2]->hasoutput)
-				out[2]->data= node_composit_get_zimage(node, rd);
+				if(out[2]->hasoutput)
+					out[2]->data= node_composit_get_zimage(node, rd);
+			}
 		}
 		
 		/* alpha and preview for both types */
@@ -242,6 +244,7 @@ static void node_composit_init_image(bNode* node)
 {
    ImageUser *iuser= MEM_callocN(sizeof(ImageUser), "node image user");
    node->storage= iuser;
+   iuser->frames= 1;
    iuser->sfra= 1;
    iuser->fie_ima= 2;
    iuser->ok= 1;