X-Git-Url: https://git.draconx.ca/gitweb/liblbx.git/blobdiff_plain/ea9655907d37782a2a505caee22f2458058784ee..a5ebd4f7732ad6846b0dc992c8d43cac636f580d:/src/image.c

diff --git a/src/image.c b/src/image.c
index 81f66e0..c1ad351 100644
--- a/src/image.c
+++ b/src/image.c
@@ -29,7 +29,7 @@ struct lbx_image {
 
 struct lbx_image *lbximg_fopen(FILE *f)
 {
-	struct lbx_image tmp = {.f = f}, *new;
+	struct lbx_image tmp = {.f = f}, *new = NULL;
 
 	if (fread(&tmp.width,  sizeof tmp.width,   1, f) != 1) goto readerr;
 	if (fread(&tmp.height, sizeof tmp.height,  1, f) != 1) goto readerr;
@@ -45,6 +45,15 @@ struct lbx_image *lbximg_fopen(FILE *f)
 	tmp.frames = letohs(tmp.frames); tmp.foff += sizeof tmp.frames;
 	tmp.wtf2   = letohs(tmp.wtf2);   tmp.foff += sizeof tmp.wtf2;
 
+	/* For some reason, the format seems to need this. */
+	tmp.offs++;
+	tmp.frames++;
+
+	if (tmp.offs <= tmp.frames) {
+		lbx_errno = LBX_EFORMAT;
+		return NULL;
+	}
+
 	/*
 	 * DEBUG ONLY.  These assertions exist to catch otherwise valid image
 	 * files which differ from what I believe to be true of all LBX images.
@@ -100,14 +109,14 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
 	if (type == 0) {
 		if (fread(&yval,  sizeof yval,  1, img->f) != 1) goto readerr;
 		yval = letohs(yval); img->foff += sizeof yval;
-
 		if (yval == 1000)
 			return 1;
-
 		if (fread(&count, sizeof count, 1, img->f) != 1) goto readerr;
 		count = letohs(count); img->foff += sizeof count;
 		if (fread(&xval,  sizeof xval,  1, img->f) != 1) goto readerr;
 		xval = letohs(xval); img->foff += sizeof xval;
+		if (xval == 1000)
+			return 1;
 
 		/* Ensure that the row fits in the image. */
 		if (img->height - img->currenty <= yval || xval >= img->width) {
@@ -211,7 +220,7 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
 				return NULL;
 			first = 0;
 
-			if (img->foff > img->offsets[frame+1]) {
+			if (!rc && img->foff > img->offsets[frame+1]) {
 				lbx_errno = LBX_EFORMAT;
 				return NULL;
 			}
@@ -272,6 +281,10 @@ lbximg_getpalette(struct lbx_image *img, struct lbx_colour palette[static 256])
 
 		if (entry[0] == 0) {
 			index++;
+			if (index >= 256) {
+				lbx_errno = LBX_EFORMAT;
+				return -1;
+			}
 		} else {
 			index = entry[0];
 		}
@@ -292,6 +305,15 @@ readerr:
 	return -1;
 }
 
+void lbximg_getinfo(struct lbx_image *img, struct lbx_imginfo *info)
+{
+	*info = (struct lbx_imginfo) {
+		.width   = img->width,
+		.height  = img->height,
+		.nframes = img->frames,
+	};
+}
+
 void lbximg_close(struct lbx_image *img)
 {
 	if (!img) return;