BUG/MINOR: qpack: fix buffer API usage on prefix integer encoding

Replace bogus call b_data() by b_room() to check if there is enough
space left in the buffer before encoding a prefix integer.

At this moment, no real scenario was found to trigger a bug related to
this change. This is probably because the buffer always contains data
(field section line and status code) before calling
qpack_encode_prefix_integer() which prevents an occurrence of this bug.

diff --git a/src/qpack-enc.c b/src/qpack-enc.c
index fca2539f4a950283d3c080cc6745453bcd1f82e5..5c4b99f4109a07356c9857d4252fda7ecd064c3e 100644 (file)
--- a/src/qpack-enc.c
+++ b/src/qpack-enc.c
@@ -33,13 +33,13 @@ static int qpack_encode_prefix_integer(struct buffer *out, int i, int prefix_siz
        BUG_ON(!prefix_size);
 
        if (i < (1 << prefix_size) - 1) {
-               if (b_data(out) < 1)
+               if (b_room(out) < 1)
                        return 1;
 
                b_putchr(out, before_prefix | i);
        }
        else {
-               if (b_data(out) < 2)
+               if (b_room(out) < 2)
                        return 1;
 
                b_putchr(out, before_prefix | ((1 << prefix_size) - 1));