This framework offers all other subsystems the ability to register
ACL matching criteria. Some generic matching functions are already
provided. Others will come soon and the framework shall evolve.
There are multiple places where the client's destination address is
required. Let's store it in the session when needed, and add a flag
to inform that it has been retrieved.
Problem reported by Andy Smith. If a client sends TCP data
and quickly closes the connection before the server connection
is established, AND the whole buffer can be sent at once when
the connection establishes, then the server side believes that
it can simply abort the connection because the buffer is empty,
without checking that some work was performed.
Fix: ensure that nothing was written before closing.
It is important when parsing configuration file to ensure that at
least one word is empty to mark the end of the line. This will be
required with ACLs in order to avoid reading past the end of line.
Since the introduction of speculative I/O, it was not always possible
to correctly detect a connection establishment. Particularly, in TCP
mode, there is no data to send and getsockopt() returns no error. The
solution consists in trying a connect() again to get its diagnostic.
tv_cmp2_ms handles multiple combinations of tv1 and tv2, but only
one form is used: (tv1 <= tv2). So it is overkill to use it everywhere.
A new function designed to do exactly this has been written for that
purpose: tv_cmp2_le. Also, removed old unused tv_* functions.
The fact that TV_ETERNITY was 0 was very awkward because it
required that comparison functions handled the special case.
Now it is ~0 and all comparisons are performed on unsigned
values, so that it is naturally greater than any other value.
A performance gain of about 2-5% has been noticed.
The rbtree-based wait queue consumes a lot of CPU. Use the ul2tree
instead. Lots of cleanups and code reorganizations made it possible
to reduce the task struct and simplify the code a bit.
The principle behind speculative I/O is to speculatively try to
perform I/O before registering the events in the system. This
considerably reduces the number of calls to epoll_ctl() and
sometimes even epoll_wait(), and manages to increase overall
performance by about 10%.
The new poller has been called "sepoll". It is used by default
on Linux when it works. A corresponding option "nosepoll" and
the command line argument "-ds" allow to disable it.
Gcc provides __attribute__((constructor)) which is very convenient
to execute functions at startup right before main(). All the pollers
have been converted to have their register() function declared like
this, so that it is not necessary anymore to call them from a centralized
file.
The pollers will now be able to speculatively call the I/O
processing functions and decide whether or not they want to
poll on those FDs. The changes primarily consist in teaching
those functions how to pass the info they got an EAGAIN.
Now fdtab can contain the FD_POLL_* events so that the pollers
which can fill them can give userful information to readers and
writers about the precise condition of wakeup.
It may be dangerous to play with fdtab before doing fd_insert()
because this last one is responsible for growing maxfd as needed.
Call fd_insert() before instead.
Some pollers such as kqueue lose their FD across fork(), meaning that
the registered file descriptors are lost too. Now when the proxies are
started by start_proxies(), the file descriptors are not registered yet,
leaving enough time for the fork() to take place and to get a new pollfd.
It will be the first call to maintain_proxies that will register them.
select, poll and epoll now have their dedicated functions and have
been split into distinct files. Several FD manipulation primitives
have been provided with each poller.
The rest of the code needs to be cleaned to remove traces of
StaticReadEvent/StaticWriteEvent. A trick involving a macro has
temporarily been used right now. Some work needs to be done to
factorize tests and sets everywhere.
Before calling http_parse_{sts,req}line(), it is necessary
to make msg->sol point to the beginning of the line. This
was not done, resulting in the proxy sometimes crashing when
URI rewriting or result rewriting was used.
logs are handled better with dedicated functions. The HTTP implementation
moved to proto_http.c. It has been cleaned up a bit. Now a frontend with
option httplog and no log will not call the function anymore.
The fiprm and beprm were added to ease the transition between
a single listener mode to frontends+backends. They are no longer
needed and make the code a bit more complicated. Remove them.
