Commit Graph

105 Commits

Author SHA1 Message Date
Ken Brown 85601de166 Cygwin: FIFO: simplify raw_read
Call NtReadFile directly instead of calling fhandler_base::raw_read.
In addition to being simpler, this gives us access to the return value
from NtReadFile.
2020-10-14 10:53:54 -04:00
Ken Brown 229be09b1b Cygwin: FIFO: improve termination of the listen_client thread
Add a method fifo_client_handler::pipe_state that queries Windows for
the state of a pipe instance.  Use this to help terminate the
listen_client thread cleanly.

If the last client handler is useless, delete it instead of declaring
it invalid.
2020-10-14 10:53:54 -04:00
Ken Brown 027adac187 Cygwin: FIFO: avoid deadlock when closing
fhandler_fifo::close could be called from a signal handler or another
thread at a time when another function is holding the fifo_client
lock.  This could prevent the listen_client thread from acting on the
thread termination event.  Avoid a deadlock by calling
fifo_client_unlock at the beginning of fhandler_fifo::close.
2020-10-14 10:53:54 -04:00
Ken Brown a92e5ecd0d Cygwin: FIFO: clean up locks
Make sure to use the fifo_client lock when (and only when) it is
needed.
2020-10-14 10:53:54 -04:00
Ken Brown d46b3f83c8 Cygwin: FIFO: add some error checking
Change the return type of fhandler_fifo::delete_client_handler from
void to int so that we can report errors.
2020-10-14 10:53:54 -04:00
Ken Brown b23dcaa411 Cygwin: FIFO: fix signal handling in raw_read and raw_write
cygwait wasn't being called correctly.

Also do some minor cleanup in raw_read and raw_write.
2020-10-14 10:53:54 -04:00
Ken Brown b990f65181 Cygwin: FIFO: respect the O_CLOEXEC flag
Set the inheritance of the Windows pipe handles according to the
O_CLOEXEC flag.  Previously the pipe was always created and opened
with OBJ_INHERIT.
2020-10-14 10:53:53 -04:00
Ken Brown 76d8d6b43c Cygwin: FIFO: code simplifications.
There's no longer a need to consider the connect_evt after fork/exec.
After stopping the listen_client thread, all client handlers should be
in the fc_connected or fc_invalid states, so their connect_evt members
won't be used again.

Also remove code in fhandler_fifo::dup that just repeats things
already done in stop_listen_client.
2020-10-14 10:53:53 -04:00
Ken Brown 91d5de57ff Cygwin: FIFO: make read_ready an auto-reset event
There's no point in allowing a writer to attempt to open until we've
created a pipe instance.
2020-10-14 10:53:53 -04:00
Ken Brown 9f37882918 Cygwin: FIFO: improve the check for the listen_client thread
Add a method fhandler_fifo::check_listen_client_thread that checks
whether the thread is running.  Use it in raw_read instead of just
testing the handle listen_client_thr.
2020-10-14 10:53:53 -04:00
Ken Brown 8885be8934 Cygwin: FIFO: set client handler flags more accurately
Reflect the fact that client handlers are only used for reading and
that, after connection, they are always nonblocking.
2020-10-14 10:53:53 -04:00
Ken Brown ccb1c73e9b Cygwin: FIFO: don't leave a pending listen request
On exit from the listen_client thread, make sure there's no pending
FSCTL_PIPE_LISTEN request.  Otherwise we might get a client connection
after restarting the thread, and we won't have a handle for
communicating with that client.

Remove the retry loop in the case of STATUS_PIPE_LISTENING; that case
shouldn't occur.

Remove the now-unused fc_connecting value from
fifo_client_connect_state.
2020-10-14 10:53:53 -04:00
Ken Brown 7cf9772f9d Cygwin: FIFO: add a HANDLE parameter to open_pipe
It's now up to the caller to pass a handle to open_pipe and, if
desired, to call set_handle on return.

This will be useful for a future commit, in which we will open a
client connection without setting an io_handle.
2020-10-14 10:53:52 -04:00
Ken Brown 3d5dc65104 Cygwin: FIFO: re-implement duplexers
When opening a duplexer, open a client connection to the first client
handler.  Previously we gave the duplexer a bogus write handle, which
was just a duplicate of the first client handler's handle.  This meant
that we had a pipe server with no clients connected, and all I/O
attempts failed with STATUS_PIPE_LISTENING.

Extend the last fcntl change to duplexers.

Remove a now unused fifo_client_handler constructor, as well as the
long unusued method fifo_client_handler::connect.

Don't create the pipe in duplex mode; the server handle will only be
used for reading.
2020-10-14 10:53:52 -04:00
Ken Brown 775d8d0242 Cygwin: FIFO: add 'record_connection' method
Future commits will have to re-use the code for recording a client
connection.  For convenience, factor out this code into a new method.
2020-10-14 10:53:52 -04:00
Ken Brown b26fab8cfa Cygwin: FIFO: remove incorrect duplexer code
raw_read had some code that was based on an incorrect implementation
of duplexers.
2020-10-14 10:53:52 -04:00
Ken Brown bd02adb85d Cygwin: FIFO: synchronize the blocking mode of a writer's pipe
The blocking mode of the Windows pipe underlying a writer is set to
match that of the writer itself when the latter is opened.  Define
fhandler_fifo::fcntl to keep the pipe and the writer in sync if the
blocking mode is changed via fcntl.
2020-10-14 10:53:52 -04:00
Ken Brown 9957a7895b Cygwin: FIFO: restart listen_client thread after fork/exec
This allows writers to connect immediately.  Previously the lct wasn't
restarted until the reader attempted to read.
2019-04-22 07:55:58 -04:00
Ken Brown 4443100b53 Cygwin: FIFO: stop the listen_client thread before fork/exec
Add methods need_fixup_before, init_fixup_before, and
fixup_before_fork_exec to accomplish this.  Stopping the thread makes
sure that the client handler lists of the parent and child remain in
sync while the forking/execing is in progress.
2019-04-20 14:31:07 -04:00
Ken Brown 252cd0ce2b Cygwin: FIFO: close connect_evt handles as soon as possible
Keeping them open too long can cause an attempt to close them twice
after a fork or exec.
2019-04-20 14:31:07 -04:00
Ken Brown 24c56e5a2c Cygwin: FIFO: avoid WFMO error in listen_client_thread
Don't set lct_termination_evt to NULL too early in
fhandler_fifo::stop_listen_client.  Doing so leads to an "Invalid
Handle" error in WFMO.
2019-04-20 14:31:07 -04:00
Ken Brown ef269531a9 Cygwin: FIFO: duplicate the i/o handle when opening a duplexer
Don't use the same i/o handle for the first client handler as is used
for the fhandler itself; this can lead to a later attempt to close the
same handle twice.  Instead use a duplicate.
2019-04-20 14:31:07 -04:00
Ken Brown 4ecea14a58 Cygwin: FIFO: stop the listen_client thread on an opening error
Don't just close the thread handle.
2019-04-20 14:31:07 -04:00
Ken Brown 230c5df2df Cygwin: FIFO: avoid hang after exec
Define fhandler:fifo::fixup_after_exec, which sets listen_client_thr
and lct_termination_evt to NULL.  This forces the listen_client thread
to restart on the first attempt to read after an exec.  Previously the
exec'd process could hang in fhandler_fifo::raw_read.
2019-04-18 19:34:07 +02:00
Ken Brown 2b4cf7622e Cygwin: FIFO: fix and simplify listen_client_thread
Remove fifo_client_handler::connect and move its code into
listen_client_thread.  That way we can check the return status when a
client handler's connect_evt is signaled.  Previously we incorrectly
assumed there was a successful connection.

Also simplify listen_client_thread in the following ways:

- Replace fhandler_fifo::disconnect_and_reconnect by a new
  delete_client_handler method.  Now we just delete invalid client
  handlers rather than trying to re-use them.

- Try to maintain a client handler list that consists of connected
  client handlers and exactly one that is listening for a connection.
  This allows us to call WaitForMultipleObjects with only two wait
  objects.

- Remove 'dummy_evt' from the fifo_client_handler struct; it is no
  longer needed.

- On exit from listen_client_thread, delete the "extra" (listening)
  client handler.  Otherwise there could be a connection that doesn't
  get recorded in the client handler list.  This could happen when a
  file descriptor is being duplicated.
2019-04-16 12:54:43 +02:00
Ken Brown bb46627871 Cygwin: FIFO: improve raw_write
Don't set the write end of the pipe to non-blocking mode if the FIFO
is opened in blocking mode.

In fhandler_fifo::raw_write in blocking mode, wait for the write to
complete rather than returning -1 with EAGAIN.

If the amount to write is large, write in smaller chunks (of size
determined by a new data member max_atomic_write), as in
fhandler_base_overlapped.

For convenience, add two new NTSTATUS codes, STATUS_THREAD_SIGNALED
and STATUS_THREAD_CANCELED, to ntdll.h.
2019-04-16 12:54:43 +02:00
Ken Brown a7d08b3ecd Cygwin: FIFO: start the listen_client thread when duping a reader
Otherwise it doesn't get started until the dup'd fd tries to read,
which delays client connections.
2019-04-16 12:54:43 +02:00
Ken Brown 7b28776d3f Cygwin: FIFO: fix clone
After copyto is called, make the new fhandler's pipe_name point to the
new fhandler's pipe_name_buf, which is a *copy* of the old fhandler's
pipe_name_buf.  Previously, get_pipe_name would return the wrong
result after a clone/dup, causing create_pipe_instance and open_pipe
to fail.

Also, stop the listen_client thread when cloning.  Otherwise the
thread can keep accepting connections that the cloned fhandler won't
know about.

Do this via a new method fhandler_fifo::stop_listen_client, extracted
from fhandler_fifo::close.
2019-04-16 12:54:43 +02:00
Ken Brown c5bc7a8065 Cygwin: FIFO: use a retry loop when opening a writer
There may be short periods when there's no pipe instance available.
Keep trying.
2019-04-16 12:54:43 +02:00
Ken Brown 6b20be0944 Cygwin: FIFO: fix the use of the read_ready event
Make read_ready a manual reset event.  It should always be set shortly
after startup of the listen_client thread and remain set until the
thread terminates.  (We don't want writers to connect without being
recorded in the client handler list.)

Remove the unnecessary code that checks for read_ready when a reader
is opening.
2019-04-16 12:54:43 +02:00
Ken Brown 3ef03376c5 Cygwin: FIFO: fix fifo_client_handler::close
Make sure that fhandler_base::close rather than fhandler_fifo::close
is called on the fhandler.  Also, delete the fhandler, since we
allocated it.
2019-04-16 12:54:43 +02:00
Ken Brown 513f050cbf Cygwin: FIFO: fix the error checking in raw_read
If the pipe is empty, we can get either ERROR_NO_DATA or
ERROR_PIPE_LISTENING.
2019-04-16 12:54:43 +02:00
Ken Brown 0c72e766e2 Cygwin: FIFO: fix a thinko in listen_client_thread 2019-04-16 12:54:43 +02:00
Ken Brown 1643789517 Cygwin: FIFO: remember the type of the fhandler
Add data members 'reader', 'writer', and 'duplexer' to the
fhandler_fifo class.  Set them in fhandler_fifo::open.  ('duplexer'
replaces the previous '_duplexer'.)

This will be useful in later commits.
2019-04-16 12:54:43 +02:00
Ken Brown 5281699926 Cygwin: FIFO: hit_eof: add a call to fifo_client_lock
The second check of nconnected needs to be protected by a lock as well
as the first.
2019-04-16 12:54:43 +02:00
Ken Brown b63843ed56 Cygwin: FIFO: rename client[] to fc_handler[]
The word "client" suggests something that holds a handle to the client
side of the pipe (in Windows terminology).  But our
fifo_client_handlers hold a handle the server side of the pipe, and
they *connect* to clients.
2019-04-16 12:54:43 +02:00
Takashi Yano a9c661a94d Cygwin: [gs]et_io_handle(): renamed to [gs]et_handle().
- Unify get_io_handle() and get_handle() to get_handle().
  Both of them returned same value; io_handle.
- Rename set_io_handle() to set_handle().
2019-03-30 20:08:36 +01:00
Ken Brown a137da74ba Cygwin: FIFO: add support for the duplex case
If a FIFO is opened with O_RDWR access, create the pipe with
read/write access, and make the first client have the handle of that
pipe as its I/O handle.

Adjust fhandler_fifo::raw_read to account for the result of trying to
read from that client if there's no data.
2019-03-27 14:01:45 +01:00
Ken Brown 1aa438a94c Cygwin: FIFO: update set_close_on_exec
Deal with each client.
2019-03-27 14:01:45 +01:00
Ken Brown e02a0f7295 Cygwin: FIFO: update fixup_after_fork
Fixup each client.  Reset listen_client_thr and lct_termination_evt.
2019-03-27 14:01:45 +01:00
Ken Brown 035bf7dc84 Cygwin: FIFO: update clone and dup
Deal with all clients.
2019-03-27 14:01:45 +01:00
Ken Brown c6e221c036 Cygwin: FIFO: improve EOF detection
Add a hit_eof method that tries to detect whether any clients are
connected.  Before concluding that there are none, it gives the
listen_client thread time to update the client data.
2019-03-27 14:01:45 +01:00
Ken Brown c75e077f99 Cygwin: FIFO: add a spinlock
Don't let listen_client_thread and raw_read access the client list
simultaneously.
2019-03-27 14:01:45 +01:00
Ken Brown 48d4cce3be Cygwin: FIFO: allow multiple writers
Introduce a 'fifo_client_handler' structure that can be used by a
reader to communicate with a writer using an instance of the named
pipe.  An fhandler_fifo opened for reading creates a thread that does
the following:

 - maintains a list of fifo_client_handlers
 - listens for_clients trying to connect
 - creates new pipe instances as needed so that there's always at
   least one available for connecting.

The pipe instances are initially created in blocking mode, but they
are set to be non-blocking after a connection is made.

fhandler_fifo::raw_read now loops through the connected clients and
reads from the first one that has data available.

New fhandler_fifo methods: add_client, listen_client,
listen_client_thread, check_listen_client_thread.

Replace the create_pipe method by create_pipe_instance, which allows
unlimited pipe instances.

New helper functions: create_event, set_pipe_non_blocking.
2019-03-27 14:01:45 +01:00
Ken Brown 5955da96e2 Cygwin: FIFO: stop using overlapped I/O
Make fhandler_fifo a derived class of fhandler_base instead of
fhandler_base_overlapped.

Replace the create_pipe macro, which is based on
fhandler_pipe::create, by new create_pipe and open_pipe methods.
These use NT functions instead of Win32 functions.  Replace fifo_name
by get_pipe_name, which returns a pointer to a UNICODE_STRING.

Remove the fnevent macro, which would now be needed only once.

Add a raw_write method, adapted from fhandler_base::raw_write.

Adapt all functions to the changes above.
2019-03-27 14:01:45 +01:00
Corinna Vinschen 323b48b975 Cygwin: lseek: return ESPIPE rather than EINVAL when called on a fifo
Thanks to Henri for tracking this down:
https://cygwin.com/ml/cygwin/2018-10/msg00062.html

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2018-10-10 13:20:45 +02:00
Corinna Vinschen 6e623e9320 Switching the Cygwin DLL to LGPLv3+, dropping commercial buyout option
Bump GPLv2+ to GPLv3+ for some files, clarify BSD 2-clause.

Everything else stays under GPLv3+.

New Linking Exception exempts resulting executables from LGPLv3 section 4.

Add CONTRIBUTORS file to keep track of licensing.

Remove 'Copyright Red Hat Inc' comments.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2016-06-23 10:09:17 +02:00
Yaakov Selkowitz 1f36328e7f Throughout, (mainly in fhandler*) fix remaining gcc 4.7 mismatch
warnings between regparm definitions and declarations.
* smallprint.cc (__small_vswprintf): Conditionalize declaration and
setting of l_opt for only x86_64.
* spawn.cc (child_info_spawn::worker): Remove unused 'pid' variable.
* thread.cc (verifyable_object_isvalid): Temporarily define as
non-inline with gcc 4.7+, regardless of target.
2013-05-01 01:20:37 +00:00
Corinna Vinschen 61522196c7 * Merge in cygwin-64bit-branch. 2013-04-23 09:44:36 +00:00
Christopher Faylor 6e75c72b89 Throughout, change __attribute__ ((regparm (N))) to just __regN. Throughout,
(mainly in fhandler*) start fixing gcc 4.7.2 mismatch between regparm
definitions and declarations.
* gendef: Define some functions to take @ declaration to accommodate _regN
defines which use __stdcall.
* gentls_offsets: Define __regN macros as empty.
* autoload.cc (wsock_init): Remove unneeded regparm attribute.
* winsup.h (__reg1): Define.
(__reg2): Define.
(__reg3): Define.
* advapi32.cc (DuplicateTokenEx): Coerce some initializers to avoid warnings
from gcc 4.7.2.
* exceptions.cc (status_info): Declare struct to use NTSTATUS.
(cygwin_exception::dump_exception): Coerce e->ExceptionCode to NTSTATUS.
* fhandler_clipboard.cc (cygnativeformat): Redefine as UINT to avoid gcc 4.7.2
warnings.
(fhandler_dev_clipboard::read): Ditto.
2013-01-21 04:34:52 +00:00