[cairo-commit] src/cairo-mempool.c

[Chris Wilson]

 src/cairo-mempool.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

New commits:
commit 01a8bf01c6508a4fea8d40371c3049e7a2f7908a
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Fri Mar 15 09:08:00 2013 +0000

    mempool: Reduce an assert into an error return for get_buddy()
    
    If we ask for a buddy that is outside of our allocation that is an
    error that should not happen with a power-of-two allocated zone...
    However, since it has been seen in the wild, we can safely return that
    there is no buddy rather than die in a too-late assert.
    
    Reported-by: Anton Eliasson <devel at antoneliasson.se>
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

diff --git a/src/cairo-mempool.c b/src/cairo-mempool.c
index 96e4a62..751ede3 100644
--- a/src/cairo-mempool.c
+++ b/src/cairo-mempool.c
@@ -157,7 +157,8 @@ get_buddy (cairo_mempool_t *pool, size_t offset, int bits)
 {
     struct _cairo_memblock *block;
 
-    assert (offset + (1 << bits) <= pool->num_blocks);
+    if (offset + (1 << bits) >= pool->num_blocks)
+	return NULL; /* invalid */
 
     if (BITTEST (pool, offset + (1 << bits) - 1))
 	return NULL; /* buddy is allocated */