util/ralloc: Add helpers for growing zero-initialized memory

Unfortunately, we can't quite follow the standard C conventions for
these because ralloc doesn't know the sizes of pointers.

Reviewed-by: Eric Anholt <[email protected]>

1 files changed, 25 insertions, 0 deletions

diff --git a/src/util/ralloc.c b/src/util/ralloc.c
index fc35661996d..0d20223d98f 100644
--- a/src/util/ralloc.c
+++ b/src/util/ralloc.c
@@ -198,6 +198,21 @@ reralloc_size(const void *ctx, void *ptr, size_t size)
 }
 
 void *
+rerzalloc_size(const void *ctx, void *ptr, size_t old_size, size_t new_size)
+{
+   if (unlikely(ptr == NULL))
+      return rzalloc_size(ctx, new_size);
+
+   assert(ralloc_parent(ptr) == ctx);
+   ptr = resize(ptr, new_size);
+
+   if (new_size > old_size)
+      memset((char *)ptr + old_size, 0, new_size - old_size);
+
+   return ptr;
+}
+
+void *
 ralloc_array_size(const void *ctx, size_t size, unsigned count)
 {
    if (count > SIZE_MAX/size)
@@ -224,6 +239,16 @@ reralloc_array_size(const void *ctx, void *ptr, size_t size, unsigned count)
    return reralloc_size(ctx, ptr, size * count);
 }
 
+void *
+rerzalloc_array_size(const void *ctx, void *ptr, size_t size,
+                     unsigned old_count, unsigned new_count)
+{
+   if (new_count > SIZE_MAX/size)
+      return NULL;
+
+   return rerzalloc_size(ctx, ptr, size * old_count, size * new_count);
+}
+
 void
 ralloc_free(void *ptr)
 {