lib: check the integrity of the default picture allocator

Ensure both the allocator and release callbacks are pointing to the default
functions, and that no cookie was provided.
This prevents the user from configuring a mix of custom and default callbacks.

1 files changed, 9 insertions, 1 deletions

diff --git a/src/lib.c b/src/lib.c
index 164a50c..af928d6 100644
--- a/src/lib.c
+++ b/src/lib.c
@@ -136,9 +136,17 @@ COLD int dav1d_open(Dav1dContext **const c_out, const Dav1dSettings *const s) {
     {
         goto error;
     }
-    if (c->allocator.alloc_picture_callback == dav1d_default_picture_alloc) {
+
+    if (c->allocator.alloc_picture_callback   == dav1d_default_picture_alloc &&
+        c->allocator.release_picture_callback == dav1d_default_picture_release)
+    {
+        if (c->allocator.cookie) goto error;
         if (dav1d_mem_pool_init(&c->picture_pool)) goto error;
         c->allocator.cookie = c->picture_pool;
+    } else if (c->allocator.alloc_picture_callback   == dav1d_default_picture_alloc ||
+               c->allocator.release_picture_callback == dav1d_default_picture_release)
+    {
+        goto error;
     }
 
     /* On 32-bit systems extremely large frame sizes can cause overflows in