This makes sure the number of reallocs is in O(log N).
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id:
1446203414-4013-2-git-send-email-kraxel@redhat.com
[ rebased to util/buffer.c ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
#include "qemu/buffer.h"
+#define BUFFER_MIN_INIT_SIZE 4096
+
void buffer_reserve(Buffer *buffer, size_t len)
{
if ((buffer->capacity - buffer->offset) < len) {
- buffer->capacity += (len + 1024);
+ buffer->capacity = pow2ceil(buffer->offset + len);
+ buffer->capacity = MAX(buffer->capacity, BUFFER_MIN_INIT_SIZE);
buffer->buffer = g_realloc(buffer->buffer, buffer->capacity);
}
}