Introducing a number of options to the multi interface that
allows for multiple pipelines to the same host, in order to
optimize the balance between the penalty for opening new
connections and the potential pipelining latency.
Two new options for limiting the number of connections:
CURLMOPT_MAX_HOST_CONNECTIONS - Limits the number of running connections
to the same host. When adding a handle that exceeds this limit,
that handle will be put in a pending state until another handle is
finished, so we can reuse the connection.
CURLMOPT_MAX_TOTAL_CONNECTIONS - Limits the number of connections in total.
When adding a handle that exceeds this limit,
that handle will be put in a pending state until another handle is
finished. The free connection will then be reused, if possible, or
closed if the pending handle can't reuse it.
Several new options for pipelining:
CURLMOPT_MAX_PIPELINE_LENGTH - Limits the pipeling length. If a
pipeline is "full" when a connection is to be reused, a new connection
will be opened if the CURLMOPT_MAX_xxx_CONNECTIONS limits allow it.
If not, the handle will be put in a pending state until a connection is
ready (either free or a pipe got shorter).
CURLMOPT_CONTENT_LENGTH_PENALTY_SIZE - A pipelined connection will not
be reused if it is currently processing a transfer with a content
length that is larger than this.
CURLMOPT_CHUNK_LENGTH_PENALTY_SIZE - A pipelined connection will not
be reused if it is currently processing a chunk larger than this.
CURLMOPT_PIPELINING_SITE_BL - A blacklist of hosts that don't allow
pipelining.
CURLMOPT_PIPELINING_SERVER_BL - A blacklist of server types that don't allow
pipelining.
See the curl_multi_setopt() man page for details.
When Curl_do() returns failure, the connection pointer could be NULL so
the code path following needs to that that into account.
Bug: http://curl.haxx.se/mail/lib-2013-03/0062.html
Reported by: Eric Hu
Remove internal separated behavior of the easy vs multi intercace.
curl_easy_perform() is now using the multi interface itself.
Several minor multi interface quirks and bugs have been fixed in the
process.
Much help with debugging this has been provided by: Yang Tse
This commit renames lib/setup.h to lib/curl_setup.h and
renames lib/setup_once.h to lib/curl_setup_once.h.
Removes the need and usage of a header inclusion guard foreign
to libcurl. [1]
Removes the need and presence of an alarming notice we carried
in old setup_once.h [2]
----------------------------------------
1 - lib/setup_once.h used __SETUP_ONCE_H macro as header inclusion guard
up to commit ec691ca3 which changed this to HEADER_CURL_SETUP_ONCE_H,
this single inclusion guard is enough to ensure that inclusion of
lib/setup_once.h done from lib/setup.h is only done once.
Additionally lib/setup.h has always used __SETUP_ONCE_H macro to
protect inclusion of setup_once.h even after commit ec691ca3, this
was to avoid a circular header inclusion triggered when building a
c-ares enabled version with c-ares sources available which also has
a setup_once.h header. Commit ec691ca3 exposes the real nature of
__SETUP_ONCE_H usage in lib/setup.h, it is a header inclusion guard
foreign to libcurl belonging to c-ares's setup_once.h
The renaming this commit does, fixes the circular header inclusion,
and as such removes the need and usage of a header inclusion guard
foreign to libcurl. Macro __SETUP_ONCE_H no longer used in libcurl.
2 - Due to the circular interdependency of old lib/setup_once.h and the
c-ares setup_once.h header, old file lib/setup_once.h has carried
back from 2006 up to now days an alarming and prominent notice about
the need of keeping libcurl's and c-ares's setup_once.h in sync.
Given that this commit fixes the circular interdependency, the need
and presence of mentioned notice is removed.
All mentioned interdependencies come back from now old days when
the c-ares project lived inside a curl subdirectory. This commit
removes last traces of such fact.
This reverts renaming and usage of lib/*.h header files done
28-12-2012, reverting 2 commits:
f871de0... build: make use of 76 lib/*.h renamed files
ffd8e12... build: rename 76 lib/*.h files
This also reverts removal of redundant include guard (redundant thanks
to changes in above commits) done 2-12-2013, reverting 1 commit:
c087374... curl_setup.h: remove redundant include guard
This also reverts renaming and usage of lib/*.c source files done
3-12-2013, reverting 3 commits:
13606bb... build: make use of 93 lib/*.c renamed files
5b6e792... build: rename 93 lib/*.c files
7d83dff... build: commit 13606bbfde follow-up 1
Start of related discussion thread:
http://curl.haxx.se/mail/lib-2013-01/0012.html
Asking for confirmation on pushing this revertion commit:
http://curl.haxx.se/mail/lib-2013-01/0048.html
Confirmation summary:
http://curl.haxx.se/mail/lib-2013-01/0079.html
NOTICE: The list of 2 files that have been modified by other
intermixed commits, while renamed, and also by at least one
of the 6 commits this one reverts follows below. These 2 files
will exhibit a hole in history unless git's '--follow' option
is used when viewing logs.
lib/curl_imap.h
lib/curl_smtp.h
A bundle is a list of all persistent connections to the same host.
The connection cache consists of a hash of bundles, with the
hostname as the key.
The benefits may not be obvious, but they are two:
1) Faster search for connections to reuse, since the hash
lookup only finds connections to the host in question.
2) It lays out the groundworks for an upcoming patch,
which will introduce multiple HTTP pipelines.
This patch also removes the awkward list of "closure handles",
which were needed to send QUIT commands to the FTP server
when closing a connection.
Now we allocate a separate closure handle and use that
one to close all connections.
This has been tested in a live system for a few weeks, and of
course passes the test suite.
This handling already works with the easy-interface code. When a request
is sent on a re-used connection that gets closed by the server at the
same time as the request is sent, the situation may occur so that we can
send the request and we discover the broken connection as a RECV_ERROR
in the PERFORM state and then the request needs to be retried on a fresh
connection. Test 64 broke with 'multi-always-internally'.
DNS cache entries populated with CURLOPT_RESOLVE were not properly freed
again when done using the multi interface.
Test case 1502 added to verify.
Bug: http://curl.haxx.se/bug/view.cgi?id=3575448
Reported by: Alex Gruz
This is a minor change in behavior after having been pointed out by Mark
Tully and discussed on the list. Initially this case would internally
call poll() with no sockets and a timeout which would equal a sleep for
that specified time.
Bug: http://curl.haxx.se/mail/lib-2012-10/0076.html
Reported by: Mark Tully
During the periods of rate limitation, the speedcheck function wasn't
called and thus the values weren't updated accordingly and it would then
easily trigger wrongly once data got transferred again.
Also, the progress callback's return code was not acknowledged in this
state so it could make an "abort" return code to get ignored and not
have the documented effect of aborting an ongoing transfer.
Bug: http://curl.haxx.se/mail/lib-2012-09/0081.html
Reported by: Jie He
/*
* Name: curl_multi_wait()
*
* Desc: Poll on all fds within a CURLM set as well as any
* additional fds passed to the function.
*
* Returns: CURLMcode type, general multi error code.
*/
CURL_EXTERN CURLMcode curl_multi_wait(CURLM *multi_handle,
struct curl_waitfd extra_fds[],
unsigned int extra_nfds,
int timeout_ms);
By reading the ->head pointer and using that instead of the ->size
number to figure out if there's a list remaining we avoid the (false
positive) clang-analyzer warning that we might dereference of a null
pointer.
In many states the easy_conn pointer is referenced and just assumed to
be working. This is an added extra check since analyzing indicates
there's a risk we can end up in these states with a NULL pointer there.
The refactoring of HTTP CONNECT handling in commit 41b0237834 that
made it protocol independent broke it for the multi interface. This fix
now introduce a better state handling and moved some logic to the
http_proxy.c source file.
Reported by: Yang Tse
Bug: http://curl.haxx.se/mail/lib-2012-03/0162.html
Backpedaled out the funny double-change of state in the multi state
machine by adding a new argument to the do_more() function to signal
completion. This way it can remain in the DO_MORE state properly until
done. Long term, the entire DO_MORE logic should be moved into the FTP
code and be hidden from the multi code as the logic is only used for
FTP.
1- Two new error codes are introduced.
CURLE_FTP_ACCEPT_FAILED to be set whenever ACCEPTing fails because of
FTP server connected.
CURLE_FTP_ACCEPT_TIMEOUT to be set whenever ACCEPTing timeouts.
Neither of these errors are considered fatal and control connection
remains OK because it could just be a firewall blocking server to
connect to the client.
2- One new setopt option was introduced.
CURLOPT_ACCEPTTIMEOUT_MS
It sets the maximum amount of time FTP client is going to wait for a
server to connect. Internal default accept timeout is 60 seconds.
If the first name server is not available, the multi interface does
not invoke the socket_cb when the DNS request to the first name server
timesout. Ensure that the list of sockets are always updated after
calling Curl_resolver_is_resolved.
This bug can be reproduced if Curl is complied with --enable_ares and
your code uses the multi socket interfaces and the
CURLMOPT_SOCKETFUNCTION option. To test try:
iptables -I INPUT \
-s $(sed -n -e '/name/{s/.* //p;q}' /etc/resolv.conf)/32 \
-j REJECT
and then run a program which uses the multi-interface.
This extends the fix from commit d7934b8bd4
When the multi state is changed within the multi_runsingle from DOING to
DO_MORE, we didn't immediately start the FTP state machine again. That
then left the FTP state in FTP_STOP. When curl_multi_fdset() was
subsequently called, the ftp_domore_getsock() function would return the
wrong fd info.
Reported by: Gokhan Sengun
After a PORT has been issued, and the multi handle would switch to the
CURLM_STATE_DO_MORE state (which is unique for FTP), libcurl would
return the wrong fdset to wait for when curl_multi_fdset() is
called. The code would blindly assume that it was waiting for a connect
of the second connection, while that isn't true immediately after the
PORT command.
Also, the function multi.c:domore_getsock() was highly FTP-centric and
therefore ugly to keep in protocol-agnostic code. I solved this problem
by introducing a new function pointer in the Curl_handler struct called
domore_getsock() which is only called during the DOMORE state for
protocols that set that pointer.
The new ftp.c:ftp_domore_getsock() function now returns fdset info about
the control connection's command/response handling while such a state is
in use, and goes over to waiting for a writable second connection first
once the commands are done.
The original problem could be seen by running test 525 and checking the
time stamps in the FTP server log. I can verify that this fix at least
fixes this problem.
Bug: http://curl.haxx.se/mail/lib-2011-10/0250.html
Reported by: Gokhan Sengun
Prevent modification of easy handle being added with curl_multi_add_handle()
unless this function actually suceeds.
Run Curl_posttransfer() to allow restoring of SIGPIPE handler when
Curl_connect() fails early in multi_runsingle().
When the progress function returns to cancel the request, we must mark
the connection to get closed and it must do to the DONE state.
do_init() must be called as early as possible so that state variables
for new connections are reset early. We could otherwise see that the old
values were still there when a connection was to be disconnected very
early and it would make it behave wrongly.
Bug: http://curl.haxx.se/mail/lib-2011-10/0006.html
Reported by: Vladimir Grishchenko
If a socket is larger than FD_SETSIZE, avoid using FD_SET() on the
platforms where this is possible.
Bug: http://curl.haxx.se/bug/view.cgi?id=3413274
Reported by: Tim Starling
Steve Holme