Instead, we now use the htx_sl coming from the HTX message. It avoids to have
too H1 specific code in version-agnostic parts. Of course, the concept of the
start-line is higly influenced by the H1, but the structure htx_sl can be
adapted, if necessary. And many things depend on a start-line during HTTP
analyzis. Using the structure htx_sl also avoid boring conversions between HTX
version and H1 version.
If there is no start-line, this offset is set to -1. Otherwise, it is the
relative address where the start-line is stored in the data block. When the
start-line is added, replaced or removed, this offset is updated accordingly. On
remove, if the start-line is no set and if the next block is a start-line, the
offset is updated. Finally, when an HTX structure is defragmented, the offset is
also updated accordingly.
The HTX start-line is now a struct. It will be easier to extend, if needed. Same
info can be found, of course. In addition it is now possible to set flags on
it. It will be used to set some infos about the message.
Some macros and functions have been added in proto/htx.h to help accessing
different parts of the start-line.
The function htx_find_blk() returns the HTX block containing data with a given
offset, relatively to the beginning of the HTX message. It is a good way to skip
outgoing data and find the first HTX block not already processed.
the functions htx_get_next() and htx_get_prev() are used to iterate on an HTX
message using blocks position. With htx_get_next_blk() and htx_get_prev_blk(),
it is possible to do the same, but with HTX blocks. Of course, internally, we
rely on position's versions to do so. But it is handy for callers to not take
care of the blocks position.
The function htx_add_data_before() can be used to add an HTX block before
another one. For instance, it could be used to add some data before the
end-of-message marker.
htx_cut_data_blk() is used to cut the beginning of a DATA block after a
part of it was tranferred. It simply advances the address, reduces the
advertised length and updates the htx's total data count.
Building with musl and gcc-5.3 for MIPS returns this :
include/common/buf.h: In function 'b_dist':
include/common/buf.h:252:2: error: unknown type name 'ssize_t'
ssize_t dist = to - from;
^
Including stdint or stddef is not sufficient there to get ssize_t,
unistd is needed as well. It's likely that other platforms will have
the same issue. This patch also addresses it in ist.h and memory.h.
Building on 32 bits gives this :
include/proto/htx.h: In function 'htx_dump':
include/proto/htx.h:443:25: warning: format '%lu' expects argument of type 'long unsigned int', but argument 8 has type 'uint64_t {aka long long unsigned int}' [-Wformat=]
fprintf(stderr, "htx:%p [ size=%u - data=%u - used=%u - wrap=%s - extra=%lu]\n",
^
In htx_dump(), fprintf() uses %lu but the value is an uint64_t so it
doesn't match on 32-bit. Let's cast this to unsigned long long and use
%llu instead.
The internal representation of an HTTP message, called HTX, is a structured
representation, unlike the old one which is a raw representation of
messages. Idea is to have a version-agnostic representation of the HTTP
messages, which can be easily used by to handle HTTP/1, HTTP/2 and hopefully
QUIC messages, and communication from one of them to another.
In this patch, we add types to define the internal representation itself and the
main functions to manipulate them.
