From 8701c535d63551b6d42d396c106e844d5b0f4abd Mon Sep 17 00:00:00 2001
From: Oneric <oneric@oneric.stub>
Date: Fri, 26 Mar 2021 16:28:29 +0100
Subject: library: replace grow_array with ASS_REALLOC_ARRAY

The latter has overflow protections for size_t indexation and element
size > 1, the former none whatsoever. Change all related vars to size_t.
Additionally, switch to exponential buffer growth.
---
 libass/ass_fontselect.c |  3 +--
 libass/ass_library.c    | 20 ++++----------------
 libass/ass_library.h    |  2 +-
 3 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/libass/ass_fontselect.c b/libass/ass_fontselect.c
index 3bf034b..d8313c5 100644
--- a/libass/ass_fontselect.c
+++ b/libass/ass_fontselect.c
@@ -992,7 +992,6 @@ static ASS_FontProvider *
 ass_embedded_fonts_add_provider(ASS_Library *lib, ASS_FontSelector *selector,
                                 FT_Library ftlib)
 {
-    int i;
     ASS_FontProvider *priv = ass_font_provider_new(selector, &ft_funcs, NULL);
     if (priv == NULL)
         return NULL;
@@ -1001,7 +1000,7 @@ ass_embedded_fonts_add_provider(ASS_Library *lib, ASS_FontSelector *selector,
         load_fonts_from_dir(lib, lib->fonts_dir);
     }
 
-    for (i = 0; i < lib->num_fontdata; ++i)
+    for (size_t i = 0; i < lib->num_fontdata; i++)
         process_fontdata(priv, lib, ftlib, i);
 
     return priv;
diff --git a/libass/ass_library.c b/libass/ass_library.c
index 21deea5..745798e 100644
--- a/libass/ass_library.c
+++ b/libass/ass_library.c
@@ -95,24 +95,13 @@ void ass_set_style_overrides(ASS_Library *priv, char **list)
         *q = strdup(*p);
 }
 
-static int grow_array(void **array, int nelem, size_t elsize)
-{
-    if (!(nelem & 31)) {
-        void *ptr = realloc(*array, (nelem + 32) * elsize);
-        if (!ptr)
-            return 0;
-        *array = ptr;
-    }
-    return 1;
-}
-
 void ass_add_font(ASS_Library *priv, const char *name, const char *data, int size)
 {
-    int idx = priv->num_fontdata;
+    size_t idx = priv->num_fontdata;
     if (!name || !data || !size)
         return;
-    if (!grow_array((void **) &priv->fontdata, priv->num_fontdata,
-                    sizeof(*priv->fontdata)))
+    if (!(idx & (idx - 32)) && // power of two >= 32, or zero --> time for realloc
+            !ASS_REALLOC_ARRAY(priv->fontdata, FFMAX(2 * idx, 32)))
         return;
 
     priv->fontdata[idx].name = strdup(name);
@@ -135,8 +124,7 @@ error:
 
 void ass_clear_fonts(ASS_Library *priv)
 {
-    int i;
-    for (i = 0; i < priv->num_fontdata; ++i) {
+    for (size_t i = 0; i < priv->num_fontdata; i++) {
         free(priv->fontdata[i].name);
         free(priv->fontdata[i].data);
     }
diff --git a/libass/ass_library.h b/libass/ass_library.h
index 8144f8e..674e06c 100644
--- a/libass/ass_library.h
+++ b/libass/ass_library.h
@@ -33,7 +33,7 @@ struct ass_library {
     char **style_overrides;
 
     ASS_Fontdata *fontdata;
-    int num_fontdata;
+    size_t num_fontdata;
     void (*msg_callback)(int, const char *, va_list, void *);
     void *msg_callback_data;
 };
-- 
cgit v1.2.3