- 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
- add set/get functions for the custom data in a tree node
- use Curl_timediff for time comparisons instead of the custom macro, as they
do the exact same things.
- add asserts to catch mistakes better
- updated test 1309 accordingly
Closes#14562
Previously an error from the callback accidentally made libcurl keep the
hash entry which would lead to the entry remaining and then potentially
getting removed *again* which would lead to internal confusions.
This is an old issue (introduced in 2b3dd01b77), caught by the new
asserts from c0233a35da.
Closes#14557
- converted the Curl_hash_count() macro to a function
- Discourage accessing struct fields directly
- Document the internal API in HASH.md
Closes#14503
`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
- Turned them all into functions to also do asserts etc.
- The llist related structs got all their fields renamed in order to make
sure no existing code remains using direct access.
- Each list node struct now points back to the list it "lives in", so
Curl_node_remove() no longer needs the list pointer.
- Rename the node struct and some of the access functions.
- Added lots of ASSERTs to verify API being used correctly
- Fix some cases of API misuse
Add docs/LLIST.md documenting the internal linked list API.
Closes#14485
Instead of having an especially "unique" linked list handler for the
main list of easy handles within the multi handle, this now uses a
regular Curl_llist for this as well.
With this change, it is also clearer that every easy handle added to a
multi handle belongs to one and only one out of three different lists:
process - the general one for normal transfer processing
pending - queued up waiting to get a connection (MSTATE_PENDING)
msgsent - transfer completed (MSTATE_MSGSENT)
An easy handle must therefore be removed from the current list before it
gets added to another.
Closes#14474
Use these words and casing more consistently across text, comments and
one curl tool output:
AIX, ALPN, ANSI, BSD, Cygwin, Darwin, FreeBSD, GitHub, HP-UX, Linux,
macOS, MS-DOS, MSYS, MinGW, NTLM, POSIX, Solaris, UNIX, Unix, Unicode,
WINE, WebDAV, Win32, winbind, WinIDN, Windows, Windows CE, Winsock.
Mostly OS names and a few more.
Also a couple of other minor text fixups.
Closes#14360
Since data can be held in connection filter buffers when sending gives
EAGAIN, add methods to query this and perform flushing of those buffers.
The transfer loop will continue sending until all upload data is
processed and the connection is flushed.
- add `CF_QUERY_SEND_PENDING` to query filters
- add `CF_CTRL_DATA_SEND_FLUSH` to flush filters
- change `Curl_req_want_send()` to query the connection
if it needs flushing
- use `Curl_req_want_send()` to determine the POLLOUT
in the PERFORMING multi state
- implement flush handling in the HTTP/2 connection filter
Closes#14271
Replace Curl_resolv_unlock() with Curl_resolv_unlink():
-replace inuse member with refcount in Curl_dns_entry
- pass Curl_dns_entry ** to unlink, so it gets always cleared
- solve potential (but unlikley) UAF in FTP's handling of looked up
Curl_dns_entry. Esp. do not use addr information after unlinking an entry.
In reality, the unlink will not free memory, as the dns entry is still
referenced by the hostcache. But this is not safe and relying on no other
code pruning the cache in the meantime.
- pass permanent flag when adding a dns entry instead of fixing timestamp
afterwards.
url.c: fold several static *resolve_* functions into one.
Closes#14195
- multi.c: when ratelimiting a transfer stops (MSTATE_RATELIMITING ->
MSTATE_PERFORMING), run the MSTATE_PERFORMING state right away
- urldata.h: factor out upload and download progress counters into a
struct, use that for passing these to progress update functions
- progress.c/getinfo.c: change names of moved progress counters
- progress.c: use new structs and a helper struct to factor repeated
calculation into static helpers
Closes#14335
connections being shutdown would register sockets for events, but then
never remove these sockets again. Nor would the shutdown effectively
been performed.
- If a socket event involves a transfer, check if that is the
connection cache internal handle and run its multi_perform()
instead (the internal handle is used for all shutdowns).
- When a timer triggers for a transfer, check also if it is
about the connection cache internal handle.
- During processing shutdowns in the connection cache, assess
the shutdown timeouts. Register a Curl_expire() of the lowest
value for the cache's internal handle.
Reported-by: Gordon Parke
Fixes#14280Closes#14296
The input string pointer to:
curl_escape
curl_easy_escape
curl_unescape
curl_easy_unescape
The running_handles pointer to:
curl_multi_perform
curl_multi_socket_action
curl_multi_socket_all
curl_multi_socket
Reported-by: icy17 on github
Fixes#14247Closes#14262
- 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
When removing an easy handle that had DoH sub-easy handles going, those
were not removed from the multi handle. Their memory was reclaimed on
curl_easy_cleanup() of the owning handle, but multi still had them in
their list.
Add `Curl_doh_close()` and `Curl_doh_cleanup()` as common point for
handling the DoH resource management. Use the `multi` present in the doh
handles (if so), for removal, as the `data->multi` might already have
been NULLed at this time.
Reported-by: 罗朝辉
Fixes#14207Closes#14212
Give warning for an empty pollset only when the connection has at least
IP connectivity. There are cases where the connect in QUIC makes another
attempt on a timeout and no socket will be available during that.
Closes#14108
- add a DEBUGASSERT for when a transfer's pollset should not be empty.
- move write unpausing from transfer loop into curl_easy_pause. This
make sure that the url_updatesocket() finds the correct state when
updating socket events.
- fix HTTP/2 proxy during connect phase to set sockets correctly
- fix test2600 to simulate a socket set
- move write unpausing from transfer loop into curl_easy_pause. This
make sure that the url_updatesocket() finds the correct state when
updating socket events.
- waiting for the resolver to deliver might not involve any sockets to
wait for. Do not generate a warning.
Fixes#14047Closes#14074
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
When libcurl discards a connection there are two phases this may go
through: "shutdown" and "closing". If a connection is aborted, the
shutdown phase is skipped and it is closed right away.
The connection filters attached to the connection implement the phases
in their `do_shutdown()` and `do_close()` callbacks. Filters carry now a
`shutdown` flags next to `connected` to keep track of the shutdown
operation.
Filters are shut down from top to bottom. If a filter is not connected,
its shutdown is skipped. Notable filters that *do* something during
shutdown are HTTP/2 and TLS. HTTP/2 sends the GOAWAY frame. TLS sends
its close notify and expects to receive a close notify from the server.
As sends and receives may EAGAIN on the network, a shutdown is often not
successful right away and needs to poll the connection's socket(s). To
facilitate this, such connections are placed on a new shutdown list
inside the connection cache.
Since managing this list requires the cooperation of a multi handle,
only the connection cache belonging to a multi handle is used. If a
connection was in another cache when being discarded, it is removed
there and added to the multi's cache. If no multi handle is available at
that time, the connection is shutdown and closed in a one-time,
best-effort attempt.
When a multi handle is destroyed, all connection still on the shutdown
list are discarded with a final shutdown attempt and close. In curl
debug builds, the environment variable `CURL_GRACEFUL_SHUTDOWN` can be
set to make this graceful with a timeout in milliseconds given by the
variable.
The shutdown list is limited to the max number of connections configured
for a multi cache. Set via CURLMOPT_MAX_TOTAL_CONNECTIONS. When the
limit is reached, the oldest connection on the shutdown list is
discarded.
- In multi_wait() and multi_waitfds(), collect all connection caches
involved (each transfer might carry its own) into a temporary list.
Let each connection cache on the list contribute sockets and
POLLIN/OUT events it's connections are waiting for.
- in multi_perform() collect the connection caches the same way and let
them peform their maintenance. This will make another non-blocking
attempt to shutdown all connections on its shutdown list.
- for event based multis (multi->socket_cb set), add the sockets and
their poll events via the callback. When `multi_socket()` is invoked
for a socket not known by an active transfer, forward this to the
multi's cache for processing. On closing a connection, remove its
socket(s) via the callback.
TLS connection filters MUST NOT send close nofity messages in their
`do_close()` implementation. The reason is that a TLS close notify
signals a success. When a connection is aborted and skips its shutdown
phase, the server needs to see a missing close notify to detect
something has gone wrong.
A graceful shutdown of FTP's data connection is performed implicitly
before regarding the upload/download as complete and continuing on the
control connection. For FTP without TLS, there is just the socket close
happening. But with TLS, the sent/received close notify signals that the
transfer is complete and healthy. Servers like `vsftpd` verify that and
reject uploads without a TLS close notify.
- added test_19_* for shutdown related tests
- test_19_01 and test_19_02 test for TCP RST packets
which happen without a graceful shutdown and should
no longer appear otherwise.
- add test_19_03 for handling shutdowns by the server
- add test_19_04 for handling shutdowns by curl
- add test_19_05 for event based shutdowny by server
- add test_30_06/07 and test_31_06/07 for shutdown checks
on FTP up- and downloads.
Closes#13976
- in phase CONNECTING/TUNNELING/PROTOCONNECT, retrieve
the socket from the connection filters and do not rely
on `conn->sockfd` being already set by the transfer.
- this applies to the default behaviour, a protocol handler
may override this via its callbacks.
- add a warning message in multi_getsock() when the transfer
is expected to have something in its pollset, but instead
it is empty.
Reported-by: saurabhsingh-dev on github
Fixes#13998Closes#14011
- When a transfer sets `data->state.select_bits`, it is
scheduled for rerun with EXPIRE_NOW. If such a transfer
is blocked (due to PAUSE, for example), this will lead to
a busy loop.
- multi.c: check for transfer block
- sendf.*: add Curl_xfer_is_blocked()
- sendf.*: add client reader `is_paused()` callback
- implement is_paused()` callback where needed
Closes#13908
- new struct curl_pollfds and struct curl_waitfds
- add structs and methods to init/add/cleanup an array of pollfd and
struct curl_waitfd. Use in multi_wait() and multi_waitfds() to
populate the sets for polling.
- place USE_WINSOCK WSAEventSelect() setting into a separate loop over
all collected pfds
Closes#13900
Currently, we use `pipe` for `wakeup_create`, which requires ***two***
file descriptors. Furthermore, given its complexity inside, `pipe` is a
bit heavyweight for just a simple event wait/notify mechanism.
`eventfd` would be a more suitable solution for this kind of scenario,
kernel also advocates for developers to use `eventfd` instead of `pipe`
in some simple use cases:
Applications can use an eventfd file descriptor instead of a pipe
(see pipe(2) in all cases where a pipe is used simply to signal
events. The kernel overhead of an eventfd file descriptor is much
lower than that of a pipe, and only one file descriptor is required
(versus the two required for a pipe).
This change adds the new backend of `eventfd` for `wakeup_create` and
uses it where available, eliminating the overhead of `pipe`. Also, it
optimizes the `wakeup_create` to eliminate the system calls that make
file descriptors non-blocking by moving the logic of setting
non-blocking flags on file descriptors to `socketpair.c` and using
`SOCK_NONBLOCK` for `socketpair(2)`, `EFD_NONBLOCK` for `eventfd(2)`.
Ref:
https://man7.org/linux/man-pages/man7/pipe.7.htmlhttps://man7.org/linux/man-pages/man2/eventfd.2.htmlhttps://man7.org/linux/man-pages/man2/socketpair.2.htmlhttps://www.gnu.org/software/gnulib/manual/html_node/eventfd.htmlCloses#13874
- determine the actual poll timeout *after* all sockets
have been collected. Protocols and connection filters may
install new timeouts during collection.
- add debug logging to test1533 where the mistake was noticed
Reported-by: Matt Jolly
Fixes#13782Closes#13825
- add `Curl_hash_add2()` that passes a destructor function for
the element added. Call element destructor instead of hash
destructor if present.
- multi: add `proto_hash` for protocol related information,
remove `struct multi_ssl_backend_data`.
- openssl: use multi->proto_hash to keep x509 shared store
- schannel: use multi->proto_hash to keep x509 shared store
- vtls: remove Curl_free_multi_ssl_backend_data() and its
equivalents in the TLS backends
Closes#13345
- Clear data->state.os_errno before transfer.
- Explain the change in behavior in the CURLINFO_OS_ERRNO doc.
- Add to the CURLINFO_OS_ERRNO doc the list of libcurl network-related
errors that may cause the errno to be saved.
data->state.os_errno is saved before libcurl returns a network-related
failure such as connection failure. It is accessible to the user via
CURLINFO_OS_ERRNO so they can get more information about the failure.
Prior to this change it wasn't cleared before transfer, so if a user
retrieved the saved errno it could be from a previous transfer. That is
because an errno is not always saved for network-related errors.
Closes https://github.com/curl/curl/pull/13574
'newurl' is allocated in some conditions and used in a few scenarios,
but there were theoretical combinations in which it would not get freed.
Move the free to happen unconditionally. Never triggered by tests, but
spotted by Coverity.
Closes#13471
- remember error encountered in invoking write callback and always fail
afterwards without further invokes
- check behaviour in test_02_17 with h2-pausing client
Reported-by: Pavel Kropachev
Fixes#13337Closes#13340
Since we can go to the CONNECT state from PENDING, potentially multiple
times for a single transfer, this change introdues a SETUP state that
happens before CONNECT when doing a new transfer.
Now, doing a redirect on a handle goes back to SETUP (not CONNECT like
before) and we initilize the connect timeout etc in SETUP. Previously,
we would do it in CONNECT but that would make it unreliable in cases
where a transfer goes in and out between CONNECT and PENDING multiple
times.
SETUP is transient, so the handle never actually stays in that state.
Additionally: take care of timeouts of PENDING transfers in
curl_multi_perform()
Ref: #13227Closes#13371
When there is a "change" in a multi handle and pending handles are moved
back to the main list to be retested if they can proceed further (for
example a previous transfer completed or a connection has a confirmed
multiplexed state), the timeout check in multi_runsingle() would not
trigger because it required an established connection.
This could make a pending tranfer go back to pending state even though
it had been "in progress" for a longer time than permitted. By removing
the requirement for an associated connection, the timeout check will be
done proper even for transfers that has not yet been assigned one.
Ref #13227
Reported-by: Rahul Krishna M
Closes#13276
- 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
A transfer may do several `SingleRequest`s for its success. This happens
regularly for authentication, follows and retries on failed connections.
The "readwrite()" calls and functions connected to those carried a `bool
*done` parameter to indicate that the current `SingleRequest` is over.
This may happen before `upload_done` or `download_done` bits of
`SingleRequest` are set.
The problem with that is now `write_resp()` protocol handlers are
invoked in places where the `bool *done` cannot be passed up to the
caller. Instead of being a bool in the call chain, it needs to become a
member of `SingleRequest`, reflecting its state.
This removes the `bool *done` parameter and adds the `done` bit to
`SingleRequest` instead. It adds `Curl_req_soft_reset()` for using a
`SingleRequest` in a follow up, clearing `done` and other
flags/counters.
Closes#13096
new struct ip_quadruple for holding local/remote addr+port
- used in data->info and conn and cf-socket.c
- copy back and forth complete struct
- add 'secondary' to conn
- use secondary in reporting success for ftp 2nd connection
Reported-by: DasKutti on github
Fixes#13084Closes#13090
- update client reader documentation
- client reader, add rewind capabilities
- tell creader to rewind on next start
- Curl_client_reset() will keep reader for future rewind if requested
- add Curl_client_cleanup() for freeing all resources independent of
rewinds
- add Curl_client_start() to trigger rewinds
- move rewind code from multi.c to sendf.c and make part of
"cr-in"'s implementation
- http, move the "resume_from" handling into the client readers
- the setup of a HTTP request is reshuffled to follow:
* determine method, target, auth negotiation
* install the client reader(s) for the request, including crlf
conversions and "chunked" encoding
* apply ranges to client reader
* concat request headers, upgrades, cookies, etc.
* complete request by determining Content-Length of installed
readers in combination with method
* send
- add methods for client readers to
* return the overall length they will generate (or -1 when unknown)
* return the amount of data on the CLIENT level, so that
expect-100 can decide if it want to apply itself
* set a "resume_from" offset or fail if unsupported
- struct HTTP has become largely empty now
- rename `Client_reader_*` to `Curl_creader_*`
Closes#13026
- 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
If the easy handle that is being added to a multi handle has previously
been used for curl_easy_perform(), there is a private multi handle here
that we can kill off. While it flushes some caches etc for the easy
handle would it be used for an easy interface transfer again after being
used in the multi stack, this cleanup simplifies behavior and uses less
memory.
Closes#12992
Curl_read/Curl_write clarifications
- replace `Curl_read()`, `Curl_write()` and `Curl_nwrite()` to 1clarify
when and at what level they operate
- send/recv of transfer related data is now done via
`Curl_xfer_send()/Curl_xfer_recv()` which no longer has
socket/socketindex as parameter. It decides on the transfer setup of
`conn->sockfd` and `conn->writesockfd` on which connection filter
chain to operate.
- send/recv on a specific connection filter chain is done via
`Curl_conn_send()/Curl_conn_recv()` which get the socket index as
parameter.
- rename `Curl_setup_transfer()` to `Curl_xfer_setup()` for naming
consistency
- clarify that the special CURLE_AGAIN handling to return `CURLE_OK`
with length 0 only applies to `Curl_xfer_send()` and CURLE_AGAIN is
returned by all other send() variants.
SingleRequest reshuffling
- move functions into request.[ch]
- differentiate between reset and free
- add Curl_req_done() to perform last actions
- add a send `bufq` to SingleRequest for future use in keeping upload data
Closes#12963
Refactoring of the client writer that passes the data to the
client/application's callback functions.
- split out into own source cw-out.[ch] from sendf.c
- move tempwrite and tempcount from data->state into the context of the
client writer
- redesign the 3 tempwrite dynbufs as a linked list of dynbufs. On
paused transfers, this allows to "record" interleaved HEADER/BODY
chunks to be "played back" in the same order on unpausing.
- keep the overall size limit of all buffered data to DYN_PAUSE_BUFFER.
On exceeding that, return CURLE_TOO_LARGE instead of
CURLE_OUT_OF_MEMORY as before.
- add method to be called when a transfer is DONE to allow writing of
any data still buffered
- when paused, record HEADER writes exactly as they come for later
playback. HEADERs are documented to be written one-by-one.
Closes#12898
