From 1f01c670c5fac1829e46ed8bc6b033e3680e645f Mon Sep 17 00:00:00 2001
From: N-R-K <79544946+N-R-K@users.noreply.github.com>
Date: Tue, 26 Oct 2021 23:41:11 +0600
Subject: [PATCH] fix: memory leak in img_load_webp (#135)

if `multi.cap` is >0 that means `multi.frames` has already been malloc-ed. by
unconditionally malloc-ing again, we're losing all the old memory.

this makes it so we're only malloc-ing (or realloc-ing) when needed.
---
 image.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/image.c b/image.c
index 062f7ad..4440497 100644
--- a/image.c
+++ b/image.c
@@ -380,12 +380,18 @@ bool img_load_webp(const fileinfo_t *file, Imlib_Image *fframe, img_t *img)
 		flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
 		img->w = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
 		img->h = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
-		img->multi.cap = info.frame_count;
-		img->multi.sel = 0;
-		img->multi.frames = emalloc(info.frame_count * sizeof(img_frame_t));
+
+		if (img->multi.cap == 0) {
+			img->multi.cap = info.frame_count;
+			img->multi.frames = emalloc(img->multi.cap * sizeof(img_frame_t));
+		} else if (info.frame_count > img->multi.cap) {
+			img->multi.cap = info.frame_count;
+			img->multi.frames = erealloc(img->multi.frames,
+			                             img->multi.cap * sizeof(img_frame_t));
+		}
 
 		/* Load and decode frames (also works on images with only 1 frame) */
-		img->multi.cnt = 0;
+		img->multi.cnt = img->multi.sel = 0;
 		while (WebPAnimDecoderGetNext(dec, &buf, &ts)) {
 			im = imlib_create_image_using_copied_data(
 			     info.canvas_width, info.canvas_height, (DATA32*)buf);