As reported here
http://libwebsockets.org/trac/ticket/11
the code for connection storm handling had rotted, fds[0] is no longer
always related to the listen socket when serving.
This patch updates it to determine the listen socket correctly to stop
infinite recursion here.
Reported-by: amn
Signed-off-by: Andy Green <andy.green@linaro.org>
*** This patch changes an API all apps use ***
Context creation parameters are getting a bit out of control, this
patch creates a struct to contain them.
All the test apps are updated accordingly.
Signed-off-by: Andy Green <andy.green@linaro.org>
A new protocol member is defined that controls the size of rx
buffer allocation per connection. For compatibility 0 size
allocates 4096, but you should adapt your protocol definition
array in the user code to declare an appropriate value.
See the changelog for more detail.
The advantage is the rx frame buffer size is now tailored to
what is expected from the protocol, rather than being fixed
to a default of 4096. If your protocol only sends frames of
a dozen bytes this allows you to only allocate an rx frame
buffer of the same size.
For example the per-connection allocation (excluding headers)
for the test server fell from ~4500 to < 750 bytes with this.
Signed-off-by: Andy Green <andy.green@linaro.org>
This gets rid of the stack buffer while serving files, and the
PATH_MAX char array that used to hold the filepath in the wsi.
It holds an extra file descriptor open while serving the file,
however it attempts to stuff the socket with as much of the
file as it can take. For files of a few KB, that typically
completes (without blocking) in the call to
libwebsockets_serve_http_file() and then closes the file
descriptor before returning.
Signed-off-by: Andy Green <andy.green@linaro.org>
- For some reason the "extern int pid_daemon" usage in libwebsockets.c would cause an "undefined symbols" linker error for the test-apps. This only happens with the CMake project, not the normal Makefiles. I have no clue why this is. Fixed it by getting the pid via a function instead.
- Added test-server-extpoll
- Renamed the library from libwebsocket -> libwebsockets
- Finalized CMake support (tested on windows only so far).
- Uses a generated lws_config.h that is included in
private-libwebsocket to pass defines, only used if CMAKE_BUILD is set.
- Support for SSL on Windows.
- Initial support for CyaSSL replacement of OpenSSL (This has been added
to my older CMake-fork but haven't been tested on this version yet).
- Fixed windows build (see below for details).
- Fixed at least the 32-bit Debug build for the existing Visual Studio
Project. (Not to keen fixing all the others when we have CMake support
anyway (which can generate much better project files)...)
- BUGFIXES:
- handshake.c
- used C99 definition of handshake_0405 function
- libwebsocket.c
- syslog not available on windows, put in ifdefs.
- Fixed previous known crash bug on Windows where WSAPoll in
Ws2_32.dll would not be present, causing the poll function pointer
being set to NULL.
- Uninitialized variable context->listen_service_extraseen would
result in stack overflow because of infinite recursion. Fixed by
initializing in libwebsocket_create_context
- SO_REUSADDR means something different on Windows compared to Unix.
- Setting a socket to nonblocking is done differently on Windows.
(This should probably broken out into a helper function instead)
- lwsl_emit_syslog -> lwsl_emit_stderr on Windows.
- private-libwebsocket.h
- PATH_MAX is not available on Windows, define as MAX_PATH
- Always define LWS_NO_DAEMONIZE on windows.
- Don't define lws_latency as inline that does nothing. inline is not
support by the Microsoft compiler, replaced with an empty define
instead. (It's __inline in MSVC)
- server.c
- Fixed nonblock call on windows
- test-ping.c
- Don't use C99 features (Microsoft compiler does not support it).
- Move non-win32 headers into ifdefs.
- Skip use of sighandler on Windows.
- test-server.c
- ifdef syslog parts on Windows.
This exposes the library version and git head hash it was built from
into LWS_LIBRARY_VERSION and LWS_BUILD_HASH.
These are combined into a version string that's both printed as a
notice log by the library and made available to the app using a new
api lws_get_library_version(). The version looks like
1.1 178d78c
Signed-off-by: Andy Green <andy.green@linaro.org>
Libwebsockets is fundamentally singlethreaded... the existence of the
fork and broadcast support, especially in the sample server is
giving the wrong idea about how to use it.
This replaces broadcast in the sample server with
libwebsocket_callback_on_writable_all_protocol(). The whole idea of
'broadcast' is removed.
All of the broadcast proxy stuff is removed: data must now be sent
from the callback only. Doing othherwise is not reliable since the
service loop may close the socket and free the wsi at any time,
invalidating a wsi pointer held by another thread (don't do that!)
Likewise the confirm_legit_wsi api added recently does not help the
other thread case, since if the wsi has been freed dereferencing the
wsi to study if it is legit or not will segfault in that case. So
this is removed too.
The overall effect is to push user code to only operate inside the
protocol callbacks or external poll loops, ie, single thread context.
Signed-off-by: Andy Green <andy.green@linaro.org>
Large chunks of struct libwebsocket members actually have a mutually
exclusive lifecycle, eg, once the http headers are finished they sit
there unused until the instance is destroyed.
This makes a big improvement in memory efficiency by making four
categories of member: always needed, needed for header processing,
needed for http processing, and needed for ws processing. The last
three are mutually exclusive and bound into a union inside the wsi.
Care needs taking now at "union transitions", although we zeroed down
the struct at init, the other union siblings have been writing the
same memory by the time later member siblings start to use it. So
it must be cleared down appropriately when we cross from one
mutually-exclusive use to another.
Signed-off-by: Andy Green <andy.green@linaro.org>
Since v13 was defined as the released ietf version the older versions
are deprecated. This patch strips out everything to do with the older
versions and gets rid of the option to send stuff unmasked.
The in-tree md5 implementation is then also deleted as nothing needs
it any more, 1280 loc are shed in all
Signed-off-by: Andy Green <andy.green@linaro.org>
The whole thing about count_protocols + 1 broadcast sockets and
associated dummy wsis is a workaround for getting a broadcast from
a different process context, if we are running with --enable-no-fork
then we don't need any of it in.
Signed-off-by: Andy Green <andy.green@linaro.org>
The new --without-extensions config flag completely removes all code
and data related to extensions from the build throughout the library
when given.
Signed-off-by: Andy Green <andy.green@linaro.org>
Move server-only stuff into their own files and make building
that depend on not having --without-server on the configure
Make fragments in other places conditional as well
Remove client-related members from struct libwebscket when
building LWS_NO_CLIENT
Apps:
normal: build test server, client, fraggle, ping
--without-client: build test server
--without-server: build test client, ping
Signed-off-by: Andy Green <andy.green@linaro.org>
Problems with rx flow control implementation were the underlying cause
of the connection stalling issue that was covered up with the udelay()
patch that was removed recently.
This get rx flow control working properly and corrects problems with
fifo management in the test server mirror protocol code too.
The rxfow control api has been changed to just set a flag, so it's very cheap
to call from user code. After the callbacks that might use the rxflow control
api the flag is checked and any pending actions done.
rx flow control now stops any rx packet coming immediately, with compessed
connections "just what was left in the pipe" might be hundreds of KBytes. To
implement that the current packet being decoded is copied into a malloc'd buffer
by the rx processing code now.
When rxflow is allows to come again, the buffer is drained and freed before any
new packet content is accepted.
Signed-off-by: Andy Green <andy.green@linaro.org>
This rips out the connection hashtable implementation along with
MAX_CLIENTS and replaces it with a dynamically allocated fds array
and lookup table along the same lines as the new extpoll implementation
from Edwin van den Oetelaar.
It detects the max number of file descriptors possible at context init
time and allocates accordingly; this can be externally controlled by
ulimit and the server run as a specific user to facilitate targeting
specific ulimit rules at it.
Many operations that translated between socket descriptors and struct
websocket or pollfd objects have had iteration removed by this patch
and under load will be a lot faster.
Signed-off-by: Andy Green <andy.green@linaro.org>
This leverages the refactor patches to introduce the ability to
disable building any client side code in the library or the client
side test apps.
This will be a considerable size saving for embedded server-only
case.
Signed-off-by: Andy Green <andy.green@linaro.org>
From an idea by Edwin van den Oetelaar <oetelaar.automatisering@gmail.com>
When testing libwebsockets with ab, Edwin found an unexpected bump in
the distribution of latencies, some connections were held back almost
the whole test duration.
http://ml.libwebsockets.org/pipermail/libwebsockets/2013-January/000006.html
Studying the problem revealed that when there are mass pending connections
amongst many active connections, we do not service the listen socket often
enough to clear the backlog, some seem to get stale violating FIFO ordering.
This patch introduces listen socket service "piggybacking", where every n
normal socket service actions we also check the listen socket and deal with
pending connections there.
Normally, it checks the listen socket gratuitously every 10 normal socket
services. However, if it finds something waiting, it forces a check on the
next normal socket service too by keeping stats on how often something was
waiting. If the probability of something waiting each time becomes high,
it will allow up to two waiting connections to be serviced for each normal
socket service.
In that way it has low burden in the normal case, but rapidly adapts by
detecting mass connection loads as found in ab.
Signed-off-by: Andy Green <andy.green@linaro.org>
