We don't store the start-line position anymore in the HTX message. Instead we
store the first block position to analyze. For now, it is almost the same. But
once all changes will be made on this part, this position will have to be used
by HTX analyzers, and only in the analysis context, to know where the analyse
should start.
When new blocks are added in an HTX message, if the first block position is not
defined, it is set. When the block pointed by it is removed, it is set to the
block following it. -1 remains the value to unset the position. the first block
position is unset when the HTX message is empty. It may also be unset on a
non-empty message, meaning every blocks were already analyzed.
From HTX analyzers point of view, this position is always set during headers
analysis. When they are waiting for a request or a response, if it is unset, it
means the analysis should wait. But once the analysis is started, and as long as
headers are not forwarded, it points to the message start-line.
As mentionned, outside the HTX analysis, no code must rely on the first block
position. So multiplexers and applets must always use the head position to start
a loop on an HTX message.
The field hdrs_bytes has been added in the structure htx_sl. It should be used
to set how many bytes are help by all headers, from the start-line to the
corresponding EOH block. it must be set to -1 if it is unknown.
This functions should be used to get the maximum size for a block, not exceeding
the max amount of bytes passed in argument. Thus max may be set to -1 to have no
limit.
It is the first block relatively to the start-line. So it is the start-line if
its position is set (sl_pos != -1), otherwise it is the head. The functions
htx_get_first() and htx_get_first_blk() can be used to get it. This change is
mandatory to consider 1xx informational messages as part of a response.
The head of an HTX message is heavily used whereas the wrap position is only
used when a block is added or removed. So it is more logical to store the head
position in the HTX message instead of the wrap one. The wrap position can be
easily deduced. To get it, the new function htx_get_wrap() may be used.
Older compilers (like gcc-3.4) warn about the use of "const" on functions
returning a struct, which makes sense since the return may only be copied :
include/common/htx.h:233: warning: type qualifiers ignored on function return type
Let's simply drop "const" here.
The upgrade is performed when an H2 preface is detected when the first request
on a connection is parsed. The CS is destroyed by setting EOS flag on it. A
special flag is added on the HTX message to warn the HTX analyzers the stream
will be closed because of an upgrade. This way, no error and no log are
emitted. When the mux h1 is released, we create a mux h2, without any CS and
passing the buffer with the unparsed H2 preface.
The function htx_drain() can now be used to drain data from an HTX message.
It will be used by other commits to fix bugs, so it must be backported to 1.9.
The previous patch clarifies the fact that the htx pointer is never null
along all the code. This test for a null will never match, didn't catch
the pointer 1 before the fix for b_is_null(), but it confuses the compiler
letting it think that any dereferences made to this pointer after this
test could actually mean we're dereferencing a null. Let's now drop this
test. This saves us from having to add impossible tests everywhere to
avoid the warning.
This should be backported to 1.9 if the b_is_null() patch is backported.
Update the comments above htxbuf() and htx_from_buf() to make it clear
that they always return valid htx pointers so that callers know they do
not have to test them. This is only true after the fix on b_is_null()
which was the only known corner case.
This should be backported to 1.9 if the b_is_null() patch is backported.
All the HTX definition is self-contained and doesn't really depend on
anything external since it's a mostly protocol. In addition, some
external similar files (like h2) also placed in common used to rely
on it, making it a bit awkward.
This patch moves the two htx.h files into a single self-contained one.
The historical dependency on sample.h could be also removed since it
used to be there only for http_meth_t which is now in http.h.
