RFC 7541 requires that dynamic table size update must occur at the
beginning of the first header block, and is signaled as SETTINGS
acknowledgement. This commit checks these conditions. If dynamic
table size update appears other than the beginning of the first header
block, it is treated as error. If SETTINGS ACK is received, and next
HEADERS header block does not have dynamic table size update, it is
treated as error.
Previously in inflater we reserve new ringbuffer when table size is
changed. This may be potentially a problem if new table size is very
large number. When inflater is not used directly by application, this
is not a problem because application can choose the buffer size. On
the other hand, if application uses inflater directly and it does not
have control of new buffer size (e.g., protocol dissector), then we
just fail to allocate large buffer in
nghttp2_hd_inflate_change_table_size() without actually use such huge
buffer. This change defers the actual allocation of buffer when it is
actually needed so that we will fail when it is absolutely needed.
* Use 1 Huffman code table for both request and response
* Remove complicated deflater side table size management
* Add encoding context update
* Fix memory leak in inflater
Tatsuhiro Tsujikawa