From ca6010789e26685d2b19a5a960fc7311fab64856 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 18 Sep 2020 07:40:30 +0530
Subject: [PATCH] Fix a memory leak when changing font sizes

had forgotten to free unused font groups
---
 docs/changelog.rst |  2 ++
 kitty/fonts.c      | 71 +++++++++++++++++++++++-----------------------
 2 files changed, 38 insertions(+), 35 deletions(-)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index 2b01cb6aa..917ef5223 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -59,6 +59,8 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 
 - Fix a regression that broke the ``move_window_to_top`` action (:pull:`2953`)
 
+- Fix a memory leak when changing font sizes
+
 
 0.18.3 [2020-08-11]
 -------------------
diff --git a/kitty/fonts.c b/kitty/fonts.c
index 9869482c3..dad465aaa 100644
--- a/kitty/fonts.c
+++ b/kitty/fonts.c
@@ -130,12 +130,48 @@ font_group_is_unused(FontGroup *fg) {
     return true;
 }
 
+void
+free_maps(Font *font) {
+#define free_a_map(type, attr) {\
+    type *s, *t; \
+    for (size_t i = 0; i < sizeof(font->attr)/sizeof(font->attr[0]); i++) { \
+        s = font->attr[i].next; \
+        while (s) { \
+            t = s; \
+            s = s->next; \
+            free(t); \
+        } \
+    }\
+    memset(font->attr, 0, sizeof(font->attr)); \
+}
+    free_a_map(SpritePosition, sprite_map);
+    free_a_map(SpecialGlyphCache, special_glyph_cache);
+#undef free_a_map
+}
+
+static inline void
+del_font(Font *f) {
+    Py_CLEAR(f->face);
+    free(f->ffs_hb_features); f->ffs_hb_features = NULL;
+    free_maps(f);
+    f->bold = false; f->italic = false;
+}
+
+static inline void
+del_font_group(FontGroup *fg) {
+    free(fg->canvas); fg->canvas = NULL;
+    fg->sprite_map = free_sprite_map(fg->sprite_map);
+    for (size_t i = 0; i < fg->fonts_count; i++) del_font(fg->fonts + i);
+    free(fg->fonts); fg->fonts = NULL;
+}
+
 static inline void
 trim_unused_font_groups(void) {
     save_window_font_groups();
     size_t i = 0;
     while (i < num_font_groups) {
         if (font_group_is_unused(font_groups + i)) {
+            del_font_group(font_groups + i);
             size_t num_to_right = (--num_font_groups) - i;
             if (!num_to_right) break;
             memmove(font_groups + i, font_groups + 1 + i, num_to_right * sizeof(FontGroup));
@@ -282,25 +318,6 @@ sprite_tracker_current_layout(FONTS_DATA_HANDLE data, unsigned int *x, unsigned
     *x = fg->sprite_tracker.xnum; *y = fg->sprite_tracker.ynum; *z = fg->sprite_tracker.z;
 }
 
-void
-free_maps(Font *font) {
-#define free_a_map(type, attr) {\
-    type *s, *t; \
-    for (size_t i = 0; i < sizeof(font->attr)/sizeof(font->attr[0]); i++) { \
-        s = font->attr[i].next; \
-        while (s) { \
-            t = s; \
-            s = s->next; \
-            free(t); \
-        } \
-    }\
-    memset(font->attr, 0, sizeof(font->attr)); \
-}
-    free_a_map(SpritePosition, sprite_map);
-    free_a_map(SpecialGlyphCache, special_glyph_cache);
-#undef free_a_map
-}
-
 void
 clear_sprite_map(Font *font) {
 #define CLEAR(s) s->filled = false; s->rendered = false; s->colored = false; s->glyph = 0; zero_at_ptr(&s->extra_glyphs); s->x = 0; s->y = 0; s->z = 0; s->ligature_index = 0;
@@ -384,22 +401,6 @@ init_font(Font *f, PyObject *face, bool bold, bool italic, bool emoji_presentati
     return true;
 }
 
-static inline void
-del_font(Font *f) {
-    Py_CLEAR(f->face);
-    free(f->ffs_hb_features); f->ffs_hb_features = NULL;
-    free_maps(f);
-    f->bold = false; f->italic = false;
-}
-
-static inline void
-del_font_group(FontGroup *fg) {
-    free(fg->canvas); fg->canvas = NULL;
-    fg->sprite_map = free_sprite_map(fg->sprite_map);
-    for (size_t i = 0; i < fg->fonts_count; i++) del_font(fg->fonts + i);
-    free(fg->fonts); fg->fonts = NULL;
-}
-
 static inline void
 free_font_groups(void) {
     if (font_groups) {