Rework the event based handling of transfers and connections to
be "localized" into a single source file with clearer dependencies.
- add multi_ev.c and multi_ev.h
- add docs/internal/MULTI-EV.md to explain the overall workings
- only do event handling book keeping when the socket callback
is set
- add handling for "connection only" event tracking, when internal
easy handles are used that are not really tied to a connection.
Used in connection pool.
- remove transfer member "last_poll" and connections "shutdown_poll"
and keep all that internal to multi_ev.c
- add CURL_TRC_M() for tracing of "multi" related things, including
event handling and connection pool operations. Add new trace
feature "multi" for trace config.
multi traces will show exactly what is going on in regard to
event handling.
- multi: trace transfers "mstate" in every CURL_TRC_M() call
- make internal trace buffer 2048 bytes and end the silliness
with +n here -m there. Adjust test 1652 expectations of resulting
length and input edge cases.
- add trace feature "lib-ids" to perfix libcurl traces with transfer
and connection ids. Useful for debugging libcurl applications.
Closes#16308
The TLS session cache is now held by the multi handle unless it is
shared, so that all easy handles within a multi handle get the benefit
of sharing the same, larger, cache.
The multi handle session cache size is set to 25, unless it is the
internal one used for the easy interface - which still uses only 3.
Closes#15982
This is a better match for what they do and the general "cpool"
var/function prefix works well.
The pool now handles very long hostnames correctly.
The following changes have been made:
* 'struct connectdata', e.g. connections, keep new members
named `destination` and ' destination_len' that fully specifies
interface+port+hostname of where the connection is going to.
This is used in the pool for "bundling" of connections with
the same destination. There is no limit on the length any more.
* Locking: all locks are done inside conncache.c when calling
into the pool and released on return. This eliminates hazards
of the callers keeping track.
* 'struct connectbundle' is now internal to the pool. It is no
longer referenced by a connection.
* 'bundle->multiuse' no longer exists. HTTP/2 and 3 and TLS filters
no longer need to set it. Instead, the multi checks on leaving
MSTATE_CONNECT or MSTATE_CONNECTING if the connection is now
multiplexed and new, e.g. not conn->bits.reuse. In that case
the processing of pending handles is triggered.
* The pool's init is provided with a callback to invoke on all
connections being discarded. This allows the cleanups in
`Curl_disconnect` to run, wherever it is decided to retire
a connection.
* Several pool operations can now be fully done with one call.
Pruning dead connections, upkeep and checks on pool limits
can now directly discard connections and need no longer return
those to the caller for doing that (as we have now the callback
described above).
* Finding a connection for reuse is now done via `Curl_cpool_find()`
and the caller provides callbacks to evaluate the connection
candidates.
* The 'Curl_cpool_check_limits()' now directly uses the max values
that may be set in the transfer's multi. No need to pass them
around. Curl_multi_max_host_connections() and
Curl_multi_max_total_connections() are gone.
* Add method 'Curl_node_llist()' to get the llist a node is in.
Used in cpool to verify connection are indeed in the list (or
not in any list) as they need to.
I left the conncache.[ch] as is for now and also did not touch the
documentation. If we update that outside the feature window, we can
do this in a separate PR.
Multi-thread safety is not achieved by this PR, but since more details
on how pools operate are now "internal" it is a better starting
point to go for this in the future.
Closes#14662
- Renames Curl_readwrite() to Curl_sendrecv() to reflect that it
is mainly about talking to the server, not reads or writes to the
client. Add a `nowp` parameter since the single caller already
has this.
- Curl_sendrecv() now runs all possible operations whenever it is
called and either it had been polling sockets or the 'select_bits'
are set.
POLL_IN/POLL_OUT are not always directly related to send/recv
operations. Filters like HTTP/2, QUIC or TLS may monitor reverse
directions. If a transfer does not want to send (KEEP_SEND), it
will not do so, as before. Same for receives.
- Curl_update_timer() now checks the absolute timestamp of an expiry
and the last/new timeout to determine if the application needs
to stop/start/restart its timer. This fixes edge cases where
updates did not happen as they should have.
- improved --test-event curl_easy_perform() simulation to handle
situations where no sockets are registered but a timeout is
in place.
- fixed bug in events_socket() that complained about removing
a socket that was unknown, when indeed it had removed the socket
just before, only it was the last in the list
- fixed conncache's internal handle to carry the multi instance
(where the cache has one) so that operations on the closure handle
trigger event callbacks correctly.
- fixed conncache to not POLL_REMOVE a socket twice when a conneciton
was closed.
Closes#14561
`data->id` is unique in *most* situations, but not in all. If a libcurl
application uses more than one connection cache, they will overlap. This
is a rare situations, but libcurl apps do crazy things. However, for
informative things, like tracing, `data->id` is superior, since it
assigns new ids in curl's serial curl_easy_perform() use.
Introduce `data->mid` which is a unique identifer inside one multi
instance, assigned on multi_add_handle() and cleared on
multi_remove_handle().
Use the `mid` in DoH operations and also in h2/h3 stream hashes.
Reported-by: 罗朝辉
Fixes#14414Closes#14499
- implement the socket hash user/reader/writer processing also
for connections that are being shut down by the connection cache.
- split out handling of current vs. last pollset socket event handling
into a function available in other code parts
- add `shutdown_poll` pollset to `connectdata` struct so that changes
in the pollset can be recorded during shutdown. (The internal handle
cannot keep it since it might be used for many connections)
Reported-by: calvin2021y on github
Fixes#14252Closes#14257
Based on the standards and guidelines we use for our documentation.
- expand contractions (they're => they are etc)
- host name = > hostname
- file name => filename
- user name = username
- man page => manpage
- run-time => runtime
- set-up => setup
- back-end => backend
- a HTTP => an HTTP
- Two spaces after a period => one space after period
Closes#14073
- Use data->multi and not data->multi_easy to refer to the active multi.
The easy handle's active multi is always data->multi.
This is a follow up to 757dfdf which changed curl so that an easy handle
used with the easy interface and then multi interface cannot have two
different multi handles associated with it at the same time
(data->multi_easy from the easy interface and data->multi from the multi
interface).
Closes https://github.com/curl/curl/pull/12665
- Move all the "upload_done" handling to request.c
- add possibility to abort sending of a request
- add `Curl_req_done_sending()` for checks
- transfer.c: readwrite_upload() now clean
- removing data->state.ulbuf and data->req.upload_fromhere
- as well as data->req.upload_present
- set data->req.upload_done on having read all from
the client and completely flushed the send buffer
- tftp, remove setting of data->req.upload_fromhere
- serves no purpose as `upload_present` is not set
and the data itself is directly `sendto()` anyway
- smtp, make upload EOB conversion a client reader
- xfer_ulbuf addition
- add xfer_ulbuf for borrowing, similar to xfer_buf
- use in file upload
- use in c-hyper body sending
- h1-proxy, remove init of data->state.uilbuf that is never used
- smb, add own send_buf instead of using data->state.ulbuf
Closes#13010
- can be borrowed by transfer during recv-write operation
- needs to be released before borrowing again
- adjustis size to `data->set.buffer_size`
- used in transfer.c readwrite_data()
Closes#12805
HTTP/1 connections that are upgraded to HTTP/2 should not be picked up
for reuse and multiplexing by other handles until the 101 switching
process is completed.
Lots-of-debgging-by: Stefan Eissing
Reported-by: Richard W.M. Jones
Bug: https://curl.se/mail/lib-2023-07/0045.htmlCloses#11557
- they are mostly pointless in all major jurisdictions
- many big corporations and projects already don't use them
- saves us from pointless churn
- git keeps history for us
- the year range is kept in COPYING
checksrc is updated to allow non-year using copyright statements
Closes#10205
Have curl_multi_init() use a much larger DNS hash table than used for
the easy interface to scale and perform better when used with _many_
host names.
curl_share_init() sets an in-between size.
Inspired-by: Ivan Tsybulin
See #9340Closes#9376
Add licensing and copyright information for all files in this repository. This
either happens in the file itself as a comment header or in the file
`.reuse/dep5`.
This commit also adds a Github workflow to check pull requests and adapts
copyright.pl to the changes.
Closes#8869
The callbacks were partially documented to support this. Now the
behavior is documented and returning error from either of these
callbacks will effectively kill all currently ongoing transfers.
Added test 530 to verify
Reported-by: Marcelo Juchem
Fixes#8083Closes#8089
... in most cases instead of 'struct connectdata *' but in some cases in
addition to.
- We mostly operate on transfers and not connections.
- We need the transfer handle to log, store data and more. Everything in
libcurl is driven by a transfer (the CURL * in the public API).
- This work clarifies and separates the transfers from the connections
better.
- We should avoid "conn->data". Since individual connections can be used
by many transfers when multiplexing, making sure that conn->data
points to the current and correct transfer at all times is difficult
and has been notoriously error-prone over the years. The goal is to
ultimately remove the conn->data pointer for this reason.
Closes#6425
Follow-up to c4e6968127
When a new transfer is created, as a resuly of an acknowledged push,
that transfer needs a download buffer allocated.
Closes#5590
More connection cache accesses are protected by locks.
CONNCACHE_* is a beter prefix for the connection cache lock macros.
Curl_attach_connnection: now called as soon as there's a connection
struct available and before the connection is added to the connection
cache.
Curl_disconnect: now assumes that the connection is already removed from
the connection cache.
Ref: #4915Closes#5009
A regression made the code use 'multiplexed' as a boolean instead of the
counter it is intended to be. This made curl try to "over-populate"
connections with new streams.
This regression came with 41fcdf71a1, shipped in curl 7.65.0.
Also, respect the CURLMOPT_MAX_CONCURRENT_STREAMS value in the same
check.
Reported-by: Kunal Ekawde
Fixes#4779Closes#4784
Repeatedly we see problems where using curl_multi_wait() is difficult or
just awkward because if it has no file descriptor to wait for
internally, it returns immediately and leaves it to the caller to wait
for a small amount of time in order to avoid occasional busy-looping.
This is often missed or misunderstood, leading to underperforming
applications.
This change introduces curl_multi_poll() as a replacement drop-in
function that accepts the exact same set of arguments. This function
works identically to curl_multi_wait() - EXCEPT - for the case when
there's nothing to wait for internally, as then this function will by
itself wait for a "suitable" short time before it returns. This
effectiely avoids all risks of busy-looping and should also make it less
likely that apps "over-wait".
This also changes the curl tool to use this funtion internally when
doing parallel transfers and changes curl_easy_perform() to use it
internally.
Closes#4163
There were a leftover few prototypes of Curl_ functions that we used to
export but no longer do, this removes those prototypes and cleans up any
comments still referring to them.
Curl_write32_le(), Curl_strcpy_url(), Curl_strlen_url(), Curl_up_free()
Curl_concat_url(), Curl_detach_connnection(), Curl_http_setup_conn()
were made static in 05b100aee2.
Curl_http_perhapsrewind() made static in 574aecee20.
For the remainder, I didn't trawl the Git logs hard enough to capture
their exact time of deletion, but they were all gone: Curl_splayprint(),
Curl_http2_send_request(), Curl_global_host_cache_dtor(),
Curl_scan_cache_used(), Curl_hostcache_destroy(), Curl_second_connect(),
Curl_http_auth_stage() and Curl_close_connections().
Closes#4096
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
... so that timeouts or other state machine actions get going again
after a changing pause state. For example, if the last delivery was
paused there's no pending socket activity.
Reported-by: sstruchtrup on github
Fixes#3994Closes#4001
As soon as a TLS backend gets ALPN conformation about the specific HTTP
version it can now set the multiplex situation for the "bundle" and
trigger moving potentially queued up transfers to the CONNECT state.
We use "conn" everywhere to be a pointer to the connection.
Introduces two functions that "attaches" and "detaches" the connection
to and from the transfer.
Going forward, we should favour using "data->conn" (since a transfer
always only has a single connection or none at all) to "conn->data"
(since a connection can have none, one or many transfers associated with
it and updating conn->data to be correct is error prone and a frequent
reason for internal issues).
Closes#3442
curl_multi_wait() was erroneously used from within
curl_easy_perform(). It could lead to it believing there was no socket
to wait for and then instead sleep for a while instead of monitoring the
socket and then miss acting on that activity as swiftly as it should
(causing an up to 1000 ms delay).
Reported-by: Antoni Villalonga
Fixes#3305Closes#3306Closes#3308
When using c-ares for asyn dns, the dns socket fd was silently closed
by c-ares without curl being aware. curl would then 'realize' the fd
has been removed at next call of Curl_resolver_getsock, and only then
notify the CURLMOPT_SOCKETFUNCTION to remove fd from its poll set with
CURL_POLL_REMOVE. At this point the fd is already closed.
By using ares socket state callback (ARES_OPT_SOCK_STATE_CB), this
patch allows curl to be notified that the fd is not longer needed
for neither for write nor read. At this point by calling
Curl_multi_closed we are able to notify multi with CURL_POLL_REMOVE
before the fd is actually closed by ares.
In asyn-ares.c Curl_resolver_duphandle we can't use ares_dup anymore
since it does not allow passing a different sock_state_cb_data
Closes#3238
When a transfer is requested to get done and it is put in the pending
queue when limited by number of connections, total or per-host, libcurl
would previously very aggressively retry *ALL* pending transfers to get
them transferring. That was very time consuming.
By reducing the aggressiveness in how pending are being retried, we
waste MUCH less time on putting transfers back into pending again.
Some test cases got a factor 30(!) speed improvement with this change.
Reported-by: Cyril B
Fixes#2369Closes#2383
Especially unpausing a transfer might have to move the socket back to the
"currently used sockets" hash to get monitored. Otherwise it would never get
any more data and get stuck. Easily triggered with pausing using the
multi_socket API.
Reported-by: Philip Prindeville
Bug: https://curl.haxx.se/mail/lib-2018-03/0048.htmlFixes#2393Closes#2391
With the introduction of expire IDs and the fact that existing timers
can be removed now and thus never expire, the concept with adding a
"latest" timer is not working anymore as it risks to not expire at all.
So, to be certain the timers actually are in line and will expire, the
plain Curl_expire() needs to be used. The _latest() function was added
as a sort of shortcut in the past that's quite simply not necessary
anymore.
Follow-up to 31b39c40cf
Reported-by: Paul Harris
Closes#1555
... since the total amount is low this is faster, easier and reduces
memory overhead.
Also, Curl_expire_done() can now mark an expire timeout as done so that
it never times out.
Closes#1472
A) reduces the timeout lists drastically
B) prevents a lot of superfluous loops for timers that expires "in vain"
when it has actually already been extended to fire later on
Visual C++ now complains about implicitly casting time_t (64-bit) to
long (32-bit). Fix this by changing some variables from long to time_t,
or explicitly casting to long where the public interface would be
affected.
Closes#1131
Previously, passing a timeout of zero to Curl_expire() was a magic code
for clearing all timeouts for the handle. That is now instead made with
the new Curl_expire_clear() function and thus a 0 timeout is fine to set
and will trigger a timeout ASAP.
This will help removing short delays, in particular notable when doing
HTTP/2.
to allow code to act differently on the situation.
Also added some more info message for the connection re-use function to
make it clearer when connections are not re-used.
