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2019-02-25io: Remove redundant read/write_coroutine assignmentsKevin Wolf
qio_channel_yield() now updates ioc->read_write/coroutine and calls qio_channel_set_aio_fd_handlers(), so the code in the handlers has become redundant and can be removed. This does not make a difference in intermediate states because aio_co_wake() really enters the coroutine immediately here: These handlers are never run in coroutine context, and we're in the right AioContext because qio_channel_attach_aio_context() asserts that the handlers are inactive. To make these conditions more obvious, assert the right AioContext. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-02-25io: Make qio_channel_yield() interruptibleKevin Wolf
Similar to how qemu_co_sleep_ns() allows preemption from an external coroutine entry, allow reentering qio_channel_yield() early. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-02-12io: add qio_task_wait_thread to join with a background threadDaniel P. Berrangé
Add the ability for a caller to wait for completion of the background thread to synchronously dispatch its result, without needing to wait for the main loop to run the idle callback. This method needs very careful usage to avoid a dangerous race condition with the free'ing of the task. The completion callback is normally invoked from an idle callback registered with the main loop context. The qio_task_wait_thread method must only be called if the completion callback has not yet run. The only safe way to achieve this is to run the qio_task_wait_thread method from the thread that executes the main loop. It is generally a bad idea to use this method since it will block execution of the main loop, however, the design of the character devices and its usage from vhostuser already requires blocking execution. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-3-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-12io: store reference to thread information in the QIOTask structDaniel P. Berrangé
Currently the struct QIOTaskThreadData is only needed by the worker thread, but a subsequent patch will need to access it from another context. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20190211182442.8542-2-berrange@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-01-24io: ensure UNIX client doesn't unlink server socketDaniel P. Berrangé
The qio_channel_socket_close method for was mistakenly unlinking the UNIX server socket, even if the channel was a client connection. This was not noticed with chardevs, since they never call close, but with the VNC server, this caused the VNC server socket to be deleted after the first client quit. The qio_channel_socket_close method also needlessly reimplemented the logic that already exists in socket_listen_cleanup(). Just call that method directly, for listen sockets only. This fixes a regression introduced in QEMU 3.0.0 with commit d66f78e1eaa832f73c771d9df1b606fe75d52a50 Author: Pavel Balaev <mail@void.so> Date: Mon May 21 19:17:35 2018 +0300 Delete AF_UNIX socket after close Fixes launchpad #1795100 Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-11-19io: return 0 for EOF in TLS session read after shutdownDaniel P. Berrangé
GNUTLS takes a paranoid approach when seeing 0 bytes returned by the underlying OS read() function. It will consider this an error and return GNUTLS_E_PREMATURE_TERMINATION instead of propagating the 0 return value. It expects apps to arrange for clean termination at the protocol level and not rely on seeing EOF from a read call to detect shutdown. This is to harden apps against a malicious 3rd party causing termination of the sockets layer. This is unhelpful for the QEMU NBD code which does have a clean protocol level shutdown, but still relies on seeing 0 from the I/O channel read in the coroutine handling incoming replies. The upshot is that when using a plain NBD connection shutdown is silent, but when using TLS, the client spams the console with Cannot read from TLS channel: Broken pipe The NBD connection has, however, called qio_channel_shutdown() at this point to indicate that it is done with I/O. This gives the opportunity to optimize the code such that when the channel has been shutdown in the read direction, the error code GNUTLS_E_PREMATURE_TERMINATION gets turned into a '0' return instead of an error. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20181119134228.11031-1-berrange@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2018-11-01websock: fix handshake leakMarc-André Lureau
Missed in f69a8bde293. Thanks Valgrind: ==955== 217 bytes in 1 blocks are definitely lost in loss record 275 of 321 ==955== at 0x483A965: realloc (vg_replace_malloc.c:785) ==955== by 0x50B6839: __vasprintf_chk (in /usr/lib64/libc-2.28.so) ==955== by 0x49AA05C: g_vasprintf (in /usr/lib64/libglib-2.0.so.0.5800.1) ==955== by 0x4983440: g_strdup_vprintf (in /usr/lib64/libglib-2.0.so.0.5800.1) ==955== by 0x126048: qio_channel_websock_handshake_send_res (channel-websock.c:162) ==955== by 0x1266E6: qio_channel_websock_handshake_send_res_ok (channel-websock.c:362) ==955== by 0x126D3E: qio_channel_websock_handshake_process (channel-websock.c:468) ==955== by 0x126EF2: qio_channel_websock_handshake_read (channel-websock.c:511) ==955== by 0x12715B: qio_channel_websock_handshake_io (channel-websock.c:571) ==955== by 0x125027: qio_channel_fd_source_dispatch (channel-watch.c:84) ==955== by 0x496326C: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.5800.1) ==955== by 0x169EC3: glib_pollfds_poll (main-loop.c:215) Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2018-06-28Delete AF_UNIX socket after closePavel Balaev
Since version 2.12.0 AF_UNIX socket created for QMP exchange is not deleted on instance shutdown. This is due to the fact that function qio_channel_socket_finalize() is called after qio_channel_socket_close(). Signed-off-by: Pavel Balaev <mail@void.so> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-20Remove unnecessary variables for function return valueLaurent Vivier
Re-run Coccinelle script scripts/coccinelle/return_directly.cocci Signed-off-by: Laurent Vivier <lvivier@redhat.com> ppc part Acked-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2018-03-27error: Remove NULL checks on error_propagate() callsLaurent Vivier
Re-run Coccinelle patch scripts/coccinelle/error_propagate_null.cocci Signed-off-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20180323143202.28879-4-lvivier@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-13sockets: move fd_is_socket() into common sockets codeDaniel P. Berrange
The fd_is_socket() helper method is useful in a few places, so put it in the common sockets code. Make the code more compact while moving it. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-03-06qio: non-default context for TLS handshakePeter Xu
A new parameter "context" is added to qio_channel_tls_handshake() is to allow the TLS to be run on a non-default context. Still, no functional change. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06qio: non-default context for async connPeter Xu
We have worked on qio_task_run_in_thread() already. Further, let all the qio channel APIs use that context. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06qio: non-default context for threaded qtaskPeter Xu
qio_task_run_in_thread() allows main thread to run blocking operations in the background. However it has an assumption on that it's always working with the default context. This patch tries to allow the threaded QIO task framework to run with non-default gcontext. Currently no functional change so far, so the QIOTasks are still always running on main context. Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06qio: store gsources for net listenersPeter Xu
Originally we were storing the GSources tag IDs. That'll be not enough if we are going to support non-default gcontext for QIO code. Switch to GSources without changing anything real. Now we still always pass in NULL, which means the default gcontext. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06qio: introduce qio_channel_add_watch_{full|source}Peter Xu
Firstly, introduce an internal qio_channel_add_watch_full(), which enhances qio_channel_add_watch() that context can be specified. Then add a new API wrapper qio_channel_add_watch_source() to return a GSource pointer rather than a tag ID. Note that the _source() call will keep a reference of GSource so that callers need to unref them explicitly when finished using the GSource. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06qio: rename qio_task_thread_resultPeter Xu
It is strange that it was called gio_task_thread_result. Rename it to follow the naming rule of the file. Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-02Include less of the generated modular QAPI headersMarkus Armbruster
In my "build everything" tree, a change to the types in qapi-schema.json triggers a recompile of about 4800 out of 5100 objects. The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h, qapi-types.h. Each of these headers still includes all its shards. Reduce compile time by including just the shards we actually need. To illustrate the benefits: adding a type to qapi/migration.json now recompiles some 2300 instead of 4800 objects. The next commit will improve it further. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-24-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
2018-02-15io/channel-command: Do not kill the child process after closing the pipeThomas Huth
We are currently facing some migration failure on s390x when running certain avocado-vt tests, e.g. when running the test type_specific.io-github-autotest-qemu.migrate.with_reboot.exec.gzip_exec. This test is using 'migrate -d "exec:nc localhost 5200"' for the migration. The problem is detected at the receiving side, where the migration stream apparently ends too early. However, the cause for the problem is at the sending side: After writing the migration stream into the pipe to netcat, the source QEMU calls qio_channel_command_close() which closes the pipe and immediately (!) kills the child process afterwards (via the function qio_channel_command_abort()). So if the sending netcat did not read the final bytes from the pipe yet, or if it did not manage to send out all its buffers yet, it is killed before the whole migration stream is passed to the destination side. QEMU can not know how much time is required by the child process to send over all migration data, so we should not kill it, neither directly nor after a delay. Let's simply wait for the child process to exit gracefully instead (this was also the behaviour of pclose() that was used in "exec:" migration before the QIOChannel rework). Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-02-15io: Add /dev/fdset/ support to QIOChannelFileRoss Lagerwall
Add /dev/fdset/ support to QIOChannelFile by calling qemu_open() instead of open() and qemu_close() instead of close(). There is a subtle semantic change since qemu_open() automatically sets O_CLOEXEC, but this doesn't affect any of the users of the function. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-02-15io: Don't call close multiple times in QIOChannelFileRoss Lagerwall
If the file descriptor underlying QIOChannelFile is closed in the io_close() method, don't close it again in the finalize() method since the file descriptor number may have been reused in the meantime. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-02-15io: Fix QIOChannelFile when creating and opening read-writeRoss Lagerwall
The code wrongly passes the mode to open() only if O_WRONLY is set. Instead, the mode should be passed when O_CREAT is set (or O_TMPFILE on Linux). Fix this by always passing the mode since open() will correctly ignore the mode if it is not needed. Add a testcase which exercises this bug and also change the existing testcase to check that the mode of the created file is correct. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-02-15io/channel-websock: handle continuous reads without any dataEdgar Kaziakhmedov
According to the current implementation of websocket protocol in QEMU, qio_channel_websock_handshake_io tries to read handshake from the channel to start communication over socket. But this approach doesn't cover scenario when socket was closed while handshaking. Therefore, if G_IO_IN is caught and qio_channel_read returns zero, error has to be set and connection has to be done. Such behaviour causes 100% CPU load in main QEMU loop, because main loop poll continues to receive and handle G_IO_IN events from websocket. Step to reproduce 100% CPU load: 1) start qemu with the simplest configuration $ qemu -vnc [::1]:1,websocket=7500 2) open any vnc listener (which doesn't follow websocket protocol) $ vncviewer :7500 3) kill listener 4) qemu main thread eats 100% CPU Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-02-15io: fix QIONetListener memory leakPaolo Bonzini
The sources array does not escape out of qio_net_listener_wait_client, so we have to free it. Reported by Coverity. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-02-09Clean up includesMarkus Armbruster
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes, with the change to target/s390x/gen-features.c manually reverted, and blank lines around deletions collapsed. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180201111846.21846-3-armbru@redhat.com>
2017-12-15io: introduce a network socket listener APIDaniel P. Berrange
The existing QIOChannelSocket class provides the ability to listen on a single socket at a time. This patch introduces a QIONetListener class that provides a higher level API concept around listening for network services, allowing for listening on multiple sockets. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-17Merge remote-tracking branch 'remotes/mjt/tags/trivial-patches-fetch' into ↵Peter Maydell
staging trivial patches for 2017-10-16 # gpg: Signature made Mon 16 Oct 2017 21:32:05 BST # gpg: using RSA key 0x701B4F6B1A693E59 # gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>" # gpg: aka "Michael Tokarev <mjt@corpit.ru>" # gpg: aka "Michael Tokarev <mjt@debian.org>" # Primary key fingerprint: 6EE1 95D1 886E 8FFB 810D 4324 457C E0A0 8044 65C5 # Subkey fingerprint: 7B73 BAD6 8BE7 A2C2 8931 4B22 701B 4F6B 1A69 3E59 * remotes/mjt/tags/trivial-patches-fetch: Add myself as maintainer for TPM code filter-mirror: segfault when specifying non existent device MAINTAINERS: Track default-configs/pci.mak MAINTAINERS: Fix Sun4v file MAINTAINERS: Clean up SCSI device section include/hw/or-irq.h: Drop unused in_irqs field io: Add missing GCC_FMT_ATTR (fix -Werror=suggest-attribute=format) os-posix: Drop misleading comment linux-user: Add some random ioctls futex: add missing header guards ui/gtk: Fix deprecation of vte_terminal_copy_clipboard gitignore: ignore check-qlit test linux-user: remove duplicate break in syscall qemu-doc.texi: remove trailing whitespace Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-10-16io: Add missing GCC_FMT_ATTR (fix -Werror=suggest-attribute=format)Stefan Weil
This fixes a compiler warning: /qemu/io/channel-websock.c:163:5: error: function might be possible candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format] Signed-off-by: Stefan Weil <sw@weilnetz.de> Acked-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-10-16io: fix mem leak in websock error pathDaniel P. Berrange
Coverity pointed out the 'date' is not free()d in the error path Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: add trace points for websocket HTTP protocol headersDaniel P. Berrange
Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: cope with websock 'Connection' header having multiple valuesDaniel P. Berrange
The noVNC server sends a header "Connection: keep-alive, Upgrade" which fails our simple equality test. Split the header on ',', trim whitespace and then check for 'upgrade' token. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: get rid of bounce buffering in websock write pathDaniel P. Berrange
Currently most outbound I/O on the websock channel gets copied into the rawoutput buffer, and then immediately copied again into the encoutput buffer, with a header prepended. Now that qio_channel_websock_encode accepts a struct iovec, we can trivially remove this bounce buffering and write directly to encoutput. In doing so, we also now correctly validate the encoutput size against the QIO_CHANNEL_WEBSOCK_MAX_BUFFER limit. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: pass a struct iovec into qio_channel_websock_encodeDaniel P. Berrange
Instead of requiring use of another Buffer, pass a struct iovec into qio_channel_websock_encode, which gives callers more flexibility in how they process data. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: get rid of qio_channel_websock_encode helper methodDaniel P. Berrange
The qio_channel_websock_encode method is only used in one place, everything else calls qio_channel_websock_encode_buffer directly. It can also be pushed up a level into the qio_channel_websock_writev method, since every other caller of qio_channel_websock_write_wire has already filled encoutput. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: simplify websocket ping reply handlingDaniel P. Berrange
We must ensure we don't get flooded with ping replies if the outbound channel is slow. Currently we do this by keeping the ping reply in a separate temporary buffer and only writing it if the encoutput buffer is completely empty. This is overly pessimistic, as it is reasonable to add a ping reply to the encoutput buffer even if it has previous data in it, as long as that previous data doesn't include a ping reply. To track this better, put the ping reply directly into the encoutput buffer, and then record the size of encoutput at this time in pong_remain. As we write encoutput to the underlying channel, we can decrement the pong_remain counter. Once it hits zero, we can accept further ping replies for transmission. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16io: monitor encoutput buffer size from websocket GSourceDaniel P. Berrange
The websocket GSource is monitoring the size of the rawoutput buffer to determine if the channel can accepts more writes. The rawoutput buffer, however, is merely a temporary staging buffer before data is copied into the encoutput buffer. Thus its size will always be zero when the GSource runs. This flaw causes the encoutput buffer to grow without bound if the other end of the underlying data channel doesn't read data being sent. This can be seen with VNC if a client is on a slow WAN link and the guest OS is sending many screen updates. A malicious VNC client can act like it is on a slow link by playing a video in the guest and then reading data very slowly, causing QEMU host memory to expand arbitrarily. This issue is assigned CVE-2017-15268, publically reported in https://bugs.launchpad.net/qemu/+bug/1718964 Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: add trace events for websockets frame handlingDaniel P. Berrange
It is useful to trace websockets frame encoding/decoding when debugging problems. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: Attempt to send websocket close messages to clientBrandon Carpenter
Make a best effort attempt to close websocket connections according to the RFC. Sends the close message, as room permits in the socket buffer, and immediately closes the socket. Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: Reply to ping framesBrandon Carpenter
Add an immediate ping reply (pong) to the outgoing stream when a ping is received. Unsolicited pongs are ignored. Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: Ignore websocket PING and PONG framesBrandon Carpenter
Keep pings and gratuitous pongs generated by web browsers from killing websocket connections. Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: Allow empty websocket payloadBrandon Carpenter
Some browsers send pings/pongs with no payload, so allow empty payloads instead of closing the connection. Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: Add support for fragmented websocket binary framesBrandon Carpenter
Allows fragmented binary frames by saving the previous opcode. Handles the case where an intermediary (i.e., web proxy) fragments frames originally sent unfragmented by the client. Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: Small updates in preparation for websocket changesBrandon Carpenter
Gets rid of unnecessary bit shifting and performs proper EOF checking to avoid a large number of repeated calls to recvmsg() when a client abruptly terminates a connection (bug fix). Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: use case insensitive check for Connection & Upgrade websock headersDaniel P. Berrange
When checking the value of the Connection and Upgrade HTTP headers the websock RFC (6455) requires the comparison to be case insensitive. The Connection value should be an exact match not a substring. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: include full error message in websocket handshake traceDaniel P. Berrange
When the websocket handshake fails it is useful to log the real error message via the trace points for debugging purposes. Fixes bug: #1715186 Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-04io: send proper HTTP response for websocket errorsDaniel P. Berrange
When any error occurs while processing the websockets handshake, QEMU just terminates the connection abruptly. This is in violation of the HTTP specs and does not help the client understand what they did wrong. This is particularly bad when the client gives the wrong path, as a "404 Not Found" would be very helpful. Refactor the handshake code so that it always sends a response to the client unless there was an I/O error. Fixes bug: #1715186 Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-09-06io: Add new qio_channel_read{, v}_all_eof functionsEric Blake
Some callers want to distinguish between clean EOF (no bytes read) vs. a short read (at least one byte read, but EOF encountered before reaching the desired length), as it allows clients the ability to do a graceful shutdown when a server shuts down at defined safe points in the protocol, rather than treating all shutdown scenarios as an error due to EOF. However, we don't want to require all callers to have to check for early EOF. So add another wrapper function that can be used by the callers that care about the distinction. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20170905191114.5959-3-eblake@redhat.com> Acked-by: Daniel P. Berrange <berrange@redhat.com>
2017-09-06io: Yield rather than wait when already in coroutineEric Blake
The new qio_channel_{read,write}{,v}_all functions are documented as yielding until data is available. When used on a blocking channel, this yield is done via qio_channel_wait() which spawns a nested event loop under the hood (so it is that secondary loop which yields as needed); but if we are already in a coroutine (at which point QIO_CHANNEL_ERR_BLOCK is only possible if we are a non-blocking channel), we want to yield the current coroutine instead of spawning a nested event loop. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20170905191114.5959-2-eblake@redhat.com> Acked-by: Daniel P. Berrange <berrange@redhat.com> [commit message updated] Signed-off-by: Eric Blake <eblake@redhat.com>
2017-09-05io: add new qio_channel_{readv, writev, read, write}_all functionsDaniel P. Berrange
These functions wait until they are able to read / write the full requested data buffer(s). Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-09-05util: remove the obsolete non-blocking connectCao jin
The non-blocking connect mechanism is obsolete, and it doesn't work well in inet connection, because it will call getaddrinfo first and getaddrinfo will blocks on DNS lookups. Since commit e65c67e4 & d984464e, the non-blocking connect of migration goes through QIOChannel in a different manner(using a thread), and nobody use this old non-blocking connect anymore. Any newly written code which needs a non-blocking connect should use the QIOChannel code, so we can drop NonBlockingConnectHandler as a concept entirely. Suggested-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>