Fix caching of combined bitmaps after complex shaping

3 files changed, 20 insertions, 10 deletions

diff --git a/libass/ass_cache.c b/libass/ass_cache.c
index 6baa924..e5e77fc 100644
--- a/libass/ass_cache.c
+++ b/libass/ass_cache.c
@@ -132,7 +132,7 @@ static void composite_destruct(void *key, void *value)
         ass_free_bitmap(v->bm_o);
     if (v->bm_s)
         ass_free_bitmap(v->bm_s);
-    free(k->str);
+    free(k->str.data);
     free(key);
     free(value);
 }
diff --git a/libass/ass_cache_template.h b/libass/ass_cache_template.h
index c91c897..29b534c 100644
--- a/libass/ass_cache_template.h
+++ b/libass/ass_cache_template.h
@@ -6,6 +6,8 @@
         type member;
 #define STRING(member) \
         char *member;
+#define BINSTRING(member) \
+        struct { size_t size; void *data; } member;
 #define FTVECTOR(member) \
         FT_Vector member;
 #define BITMAPHASHKEY(member) \
@@ -25,6 +27,9 @@
             a->member == b->member &&
 #define STRING(member) \
             strcmp(a->member, b->member) == 0 &&
+#define BINSTRING(member) \
+            a->member.size == b->member.size && \
+            memcmp(a->member.data, b->member.data, a->member.size) == 0 &&
 #define FTVECTOR(member) \
             a->member.x == b->member.x && a->member.y == b->member.y &&
 #define BITMAPHASHKEY(member) \
@@ -44,6 +49,9 @@
         hval = fnv_32a_buf(&p->member, sizeof(p->member), hval);
 #define STRING(member) \
         hval = fnv_32a_str(p->member, hval);
+#define BINSTRING(member) \
+        hval = fnv_32a_buf(&p->member.size, sizeof(p->member.size), hval); \
+        hval = fnv_32a_buf(p->member.data, p->member.size, hval);
 #define FTVECTOR(member) GENERIC(, member.x); GENERIC(, member.y);
 #define BITMAPHASHKEY(member) { \
         unsigned temp = bitmap_hash(&p->member, sizeof(p->member)); \
@@ -152,7 +160,7 @@ START(composite, composite_hash_key)
     GENERIC(int, shift_x)
     GENERIC(int, shift_y)
     FTVECTOR(advance)
-    STRING(str)
+    BINSTRING(str)
 END(CompositeHashKey)
 
 #undef START
diff --git a/libass/ass_render.c b/libass/ass_render.c
index 832ba79..0cec412 100644
--- a/libass/ass_render.c
+++ b/libass/ass_render.c
@@ -1103,7 +1103,8 @@ static void fill_composite_hash(CompositeHashKey *hk, CombinedBitmapInfo *info)
     hk->border_style = info->border_style;
     hk->has_outline = info->has_outline;
     hk->is_drawing = info->is_drawing;
-    hk->str = info->str;
+    hk->str.size = info->str_length;
+    hk->str.data = info->str;
     hk->chars = info->chars;
     hk->shadow_x = info->shadow_x;
     hk->shadow_y = info->shadow_y;
@@ -2447,9 +2448,10 @@ ass_render_event(ASS_Renderer *render_priv, ASS_Event *event,
 
                 current_info->bm = current_info->bm_o = current_info->bm_s = NULL;
 
-                current_info->max_str_length = MAX_STR_LENGTH_INITIAL;
+                current_info->max_str_length =
+                    MAX_STR_LENGTH_INITIAL * sizeof(info->glyph_index);
                 current_info->str_length = 0;
-                current_info->str = malloc(MAX_STR_LENGTH_INITIAL);
+                current_info->str = malloc(current_info->max_str_length);
                 current_info->chars = 0;
 
                 current_info->w = current_info->h = current_info->o_w = current_info->o_h = 0;
@@ -2459,19 +2461,19 @@ ass_render_event(ASS_Renderer *render_priv, ASS_Event *event,
             if(info->drawing){
                 free(current_info->str);
                 current_info->str = strdup(info->drawing->text);
+                current_info->str_length = strlen(info->drawing->text);
                 current_info->is_drawing = 1;
                 ass_drawing_free(info->drawing);
             }else{
-                current_info->str_length +=
-                    ass_utf8_put_char(
-                        current_info->str + current_info->str_length,
-                        info->symbol);
+                int length = current_info->str_length;
                 current_info->chars++;
-                if(current_info->str_length > current_info->max_str_length - 5){
+                current_info->str_length += sizeof(info->glyph_index);
+                if(current_info->str_length > current_info->max_str_length){
                     current_info->max_str_length *= 2;
                     current_info->str = realloc(current_info->str,
                                                 current_info->max_str_length);
                 }
+                *(int *)(current_info->str + length) = info->glyph_index;
             }
 
             current_info->has_outline = current_info->has_outline || !!info->bm_o;