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
This replacing of eight leading spaces into tabs was already done for
the embedded uncompressed version in tool_hugehelp.c so it does not save
anything there. But the gzip compressed version ends up almost 2K
smaller.
The output in a terminal should be identical.
Before using TABs:
curl.txt 282492 bytes
curl.txt.gz 73261 bytes
With this change applied:
curl.txt 249382 bytes
curl.txt.gz 71470 bytes
Closes#14016
- Parse etag and content-disposition headers for 3xx replies.
For example, a server may send a content-disposition filename header
with a redirect reply (3xx) but not with the final response (2xx).
Without this change curl would ignore the server's specified filename
and continue to use the filename extracted from the user-specified URL.
Prior to this change, 75d79a4 had limited etag and content-disposition
to 2xx replies only.
Tests-by: Daniel Stenberg
Reported-by: Morgan Willcock
Fixes https://github.com/curl/curl/issues/13302Closes#13484
A newly introduced use of getsockname() in the cli tool makes it require
the ascii wrapper module, which is not available outside of the library:
as the tool only uses the address family field (binary), disable
wrappers outside of libcurl.
Fix setsockopt() parameter type mismatch using a (void *) cast.
Sync ILE/RPG binding.
Closes#13930
As the list of variable names grows, doing a simple loop to find the
name get increasingly worse. This switches to a bsearch.
Also: do a case sensitive check for the variable name. The names have
not been documented to be case insensitive and there is no point in
having them so.
Closes#13914
Multipath TCP (MPTCP), standardized in RFC8684 [1], is a TCP extension
that enables a TCP connection to use different paths.
Multipath TCP has been used for several use cases. On smartphones, MPTCP
enables seamless handovers between cellular and Wi-Fi networks while
preserving established connections. This use-case is what pushed Apple
to use MPTCP since 2013 in multiple applications [2]. On dual-stack
hosts, Multipath TCP enables the TCP connection to automatically use the
best performing path, either IPv4 or IPv6. If one path fails, MPTCP
automatically uses the other path.
To benefit from MPTCP, both the client and the server have to support
it. Multipath TCP is a backward-compatible TCP extension that is enabled
by default on recent Linux distributions (Debian, Ubuntu, Redhat, ...).
Multipath TCP is included in the Linux kernel since version 5.6 [3]. To
use it on Linux, an application must explicitly enable it when creating
the socket. No need to change anything else in the application.
This attached patch adds an --mptcp option which allows the creation of
an MPTCP socket instead of TCP on Linux. If Multipath TCP is not
supported on the system, an error will be reported. It is important to
note that if the end server doesn't support MPTCP, the connection will
continue after a seamless fallback to TCP.
Link: https://www.rfc-editor.org/rfc/rfc8684.html [1]
Link: https://www.tessares.net/apples-mptcp-story-so-far/ [2]
Link: https://www.mptcp.dev [3]
Co-developed-by: Dorian Craps (@CrapsDorian) <doriancraps@gmail.com>
Co-developed-by: Olivier Bonaventure (@obonaventure) <Olivier.Bonaventure@uclouvain.be>
Co-developed-by: Matthieu Baerts (@matttbe) <matttbe@kernel.org>
Signed-off-by: Dorian Craps <dorian.craps@student.vinci.be>
Closes#13278
Add new job to test building for UWP (aka `CURL_WINDOWS_APP`).
Fix fallouts when building for UWP:
- rand: do not use `BCryptGenRandom()`.
- cmake: disable using win32 LDAP.
- cmake: disable telnet.
- version_win32: fix code before declaration.
- schannel: disable `HAS_MANUAL_VERIFY_API`.
- schannel: disable `SSLSUPP_PINNEDPUBKEY`
and make `schannel_checksum()` a stub.
Ref: e178fbd40a#1429
- schannel: make `cert_get_name_string()` a failing stub.
- system_win32: make `Curl_win32_impersonating()` a failing stub.
- system_win32: try to fix `Curl_win32_init()` (untested).
- threads: fix to use `CreateThread()`.
- src: disable searching `PATH` for the CA bundle.
- src: disable bold text support and capability detection.
- src: disable `getfiletime()`/`setfiletime()`.
- tests: make `win32_load_system_library()` a failing stub.
- tests/server/util: make it compile.
- tests/server/sockfilt: make it compile.
- tests/lib3026: fix to use `CreateThread()`.
See individual commits for build error details.
Some of these fixes may have better solutions, and some may not work
as expected. The goal of this patch is to make curl build for UWP.
Closes#13870
This removes unnecessary line wraps when the terminal is wider than 79
columns and it also makes messages look better in narrower terminals.
The get_terminal_columns() function is not split out into its own source
file.
Suggested-by: Elliott Balsley
Fixes#13804Closes#13808
`CURLDEBUG` is meant to enable memory tracking, but in a bunch of cases,
it was protecting debug features that were supposed to be guarded with
`DEBUGBUILD`.
Replace these uses with `DEBUGBUILD`.
This leaves `CURLDEBUG` uses solely for its intended purpose: to enable
the memory tracking debug feature.
Also:
- autotools: rely on `DEBUGBUILD` to enable `checksrc`.
Instead of `CURLDEBUG`, which worked in most cases because debug
builds enable `CURLDEBUG` by default, but it's not accurate.
- include `lib/easyif.h` instead of keeping a copy of a declaration.
- add CI test jobs for the build issues discovered.
Ref: https://github.com/curl/curl/pull/13694#issuecomment-2120311894Closes#13718
To avoid getting stuck in a busy-loop when nothing is read from stdin,
this function now checks the call rate and might enforce a short sleep
when called repeatedly without uploading anything. It is a crude
work-around to avoid a 100% busy CPU.
Reported-by: magisterquis on hackerone
Fixes#13174Closes#13506
This fixes a regression of 75d79a4486. The
code in tool-operate truncated the etag save file, under the assumption
that the file would be written with a new etag value. However since
75d79a4486 that might not be the case
anymore and could result in the file being truncated when --etag-compare
and --etag-save was used and that the etag value matched with what the
server responded. Instead the truncation should not be done when a new
etag value should be written.
Test 3204 was added to verify that the file with the etag value doesn't
change the contents when used by --etag-compare and --etage-save and
that value matches with what the server returns on a non 2xx response.
Closes#13432
... in the option argument.
Typically this is a mistake done when copying example command lines from
online documentation using the wrong quote character.
Presumably there are also other potential quote characters that might be
used, and this check is done without even knowing that unicode is used!
Reported-by: Sanjay Pujare
Fixes#13214Closes#13215
The curlx one was once introduced when we still considered dropping the
libcurl function at some point. To reduce confusion and to make it
easier to understand when curl_free() should be used, use the actual
libcurl function call directly instead.
Closes#13230
The option is really two enums ORed together, so it needs special
attention to make the code output nice.
Added test 1481 to verify. Both the server and the proxy versions.
Reported-by: Boris Verkhovskiy
Fixes#13127Closes#13129
... correctly, even when they follow an existing one without a space in
between.
Verify with test 467
Follow-up to 07dd60c05b
Reported-by: Geeknik Labs
Fixes#13101Closes#13102
```
src\tool_operate.c(541,33): warning C4459: declaration of 'm' hides global declaration [_bld\src\curl.vcxproj]
_bld\src\tool_hugehelp.c(8,27):
see declaration of 'm'
src\tool_paramhlp.c(307,14): warning C4459: declaration of 'm' hides global declaration [_bld\src\curl.vcxproj]
src\tool_progress.c(118,16): warning C4459: declaration of 'm' hides global declaration [_bld\src\curl.vcxproj]
src\tool_writeout.c(288,31): warning C4459: declaration of 'm' hides global declaration [_bld\src\curl.vcxproj]
```
Ref: https://ci.appveyor.com/project/curlorg/curl/builds/49348159/job/51ee75cd2n0wj6lc#L614
Reviewed-by: Daniel Stenberg
Closes#13077
All CR and LF bytes should be stripped, as documented, and all other
bytes are inluded in the data. Starting now, it also excludes null bytes
as they would otherwise also cut the data short.
Reported-by: Simon K
Fixes#13063Closes#13064
Use a plain array and puts() every line, also allows us to provide the
strings without ending newlines.
- merge blank lines into the next one as a prefixed newline.
- turn eight consecutive spaces into a tab (since they can only be on the
left side of text)
- the newly generated tool_hugehelp is 3K lines shorter and 50K smaller
- modifies the top logo layout a little by reducing the indent
Closes#13047
Create ASCII version of manpage without nroff
- build src/tool_hugegelp.c from the ascii manpage
- move the the manpage and the ascii version build to docs/cmdline-opts
- remove all use of nroff from the build process
- should make the build entirely reproducible (by avoiding nroff)
- partly reverts 2620aa9 to build libcurl option man pages one by one
in cmake because the appveyor builds got all crazy until I did
The ASCII version of the manpage
- is built with gen.pl, just like the manpage is
- has a right-justified column making the appearance similar to the previous
version
- uses a 4-space indent per level (instead of the old version's 7)
- does not do hyphenation of words (which nroff does)
History
We first made the curl build use nroff for building the hugehelp file in
December 1998, for curl 5.2.
Closes#13047
