- Previously, the PID_NEW_PG flag was also used as a marker for GDB
with non-cygwin inferior, unlike its original meaning. With this
patch, the condition exec_dwProcessId == dwProcessId is used as a
marker for that instead.
- With this patch, some pty functions/variables have been renamed
so that the name *pcon* is not used for those that are called
even when the pseudo console is not active.
- This patch fixes the handle leak which occurs when exec() fails
with an error. The duplicated handles will be closed when the
exec'ed process is terminated. However, if exec() fails, the code
path does not reach to the code closing the duplicated handles.
To implement this fix more appropriately, the setup, cleanup and
closing pty codes which was previously located in spawn.cc are
encapsulated into the fhandler_pty_slave class functions.
- In tty_min::setpgid(), a pointer to fhandler instance is casted to
fhandler_pty_slave and accessed even if terminal is not a pty slave.
This patch fixes the issue.
- With this patch, the code to wait for completion of forwarding of
output from non-cygwin app is revised so that it can more reliably
detect the completion.
- If master_fwd_thread is terminated by cygthread::terminate_thread(),
the opportunity to release tmp_pathbuf is missed, resulting in a
memory leak. This patch fixes the issue.
- GDB inferior may be suspended while the inferior grabs mutex.
This causes deadlock in terminal I/O. With this patch, timeout
for waiting mutex is set to 0 for the debugger process when the
process calls CreateProcess() with DEBUG_PROCESS flag to avoid
deadlock. This may cause the race issue in GDB, however, there
is no other way than that.
Addresses:
https://cygwin.com/pipermail/cygwin-developers/2021-December/012542.html
- This patch fixes the failure of input switching between io_handle
and io_handle_nat. This very rarely happens, however, input is
wrongly switched to io_handle_nat even though the non-cygwin app
is in the background.
- Currently, functions/variables regarding the handles for cygwin
apps are with "_cyg", and those of handles for non-cygwin apps
are without "_cyg", such as get_handle_cyg() and get_handle().
This patch renames these to the names without "_nat" and with
"_nat" respectively, such as get_handle() and get_handle_nat().
- Currently, console read() keeps reading after SIGWINCH is sent
even if SA_RESTART flag is not set. With this patch, read()
returns EINTR on SIGWINCH if SA_RESTART flag is not set.
The same problem for SIGQUIT and SIGTSTP has also been fixed.
- Currently, input transfer is performed every time one line is read(),
if the non-cygwin app is running in the background. With this patch,
transfer is triggered by setpgid() rather than read() so that the
unnecessary input transfer can be reduced much in that situation.
- After commit bb428520, there has been the disadvantage:
7) Pseudo console cannot be activated if it is already activated for
another process on same pty.
This patch clears this disadvantage.
- After commit bb428520, there has been the disadvantage:
2) The apps which use console API cannot be debugged with gdb. This
is because pseudo console is not activated since gdb uses
CreateProcess() rather than exec(). Even with this limitation,
attaching gdb to native app, in which pseudo console is already
activated, works.
This patch clears this disadvantage.
- After commit bb428520, there has been the disadvantage:
4) Code page cannot be changed by chcp.com. Acctually, chcp works
itself and changes code page of its own pseudo console. However,
since pseudo console is recreated for another process, it cannot
inherit the code page.
This patch clears this disadvantage.
- PTY has a problem that the key input, which is typed during windows
native app is running, disappears when it returns to shell. This is
beacuse pty has two input pipes, one is for cygwin apps and the other
one is for native windows apps. The key input during windows native
program is running is sent to the second input pipe while cygwin
shell reads input from the first input pipe. This issue had been
fixed once by commit 29431fcb, however, the new implementation of
pseudo console support by commit bb428520 could not inherit this
feature. This patch realize transfering input data between these
two pipes bidirectionally by utilizing cygwin-console-helper process.
The helper process is launched prior to starting the non-cygwin app,
however, exits immediately unlike previous implementation.
- After commit 232fde0e, pty changes console code page when the first
non-cygwin app is executed. If pty is started in real console device,
pty changes the code page of root console. This causes very annoying
result because changing code page changes the font of command prompt
if console is in legacy mode. This patch avoids this by creating a
new invisible console for the first pty started in console device.
- Calling ResizePseudoConsole() generates some escape sequences.
Due to this behaviour, if the output of non-cygwin app is piped
to less, screen is sometimes distorted when the screen is resized.
With this patch, ResizePseudoConsole() is not called if stdout is
redirected.
- Pseudo console internally sends escape sequence CSI6n (query cursor
position) on startup of non-cygwin apps. If the terminal does not
support CSI6n, CreateProcess() hangs waiting for response. To prevent
hang, this patch disables pseudo console if the terminal does not
have CSI6n. This is checked on the first execution of non-cygwin
app using the following steps.
1) Check if the terminal support ANSI escape sequences by looking
into terminfo database. If terminfo has cursor_home (ESC [H),
the terminal is supposed to support ANSI escape sequences.
2) If the terminal supports ANSI escape sequneces, send CSI6n for
a test and wait for a responce for 40ms.
3) If there is a responce within 40ms, CSI6n is supposed to be
supported.
Also set-title capability is checked, and removes escape sequence
for setting window title if the terminal does not have the set-
title capability.
- In this implementation, pseudo console is created for each native
console app. Advantages and disadvantages of this implementation
over the previous implementation are as follows.
Advantages:
1) No performance degradation in pty output for cygwin process.
https://cygwin.com/pipermail/cygwin/2020-February/243858.html
2) Free from the problem caused by difference of behaviour of control
sequences between real terminal and pseudo console.
https://cygwin.com/pipermail/cygwin/2019-December/243281.htmlhttps://cygwin.com/pipermail/cygwin/2020-February/243855.html
3) Free from the problem in cgdb and emacs gud.
https://cygwin.com/pipermail/cygwin/2020-January/243601.htmlhttps://cygwin.com/pipermail/cygwin/2020-March/244146.html
4) Redrawing screen on executing native console apps is not necessary.
5) cygwin-console-helper is not necessary for the pseudo console
support.
6) The codes for pseudo console support are much simpler than that
of the previous one.
Disadvantages:
1) The cygwin program which calls console API directly does not work.
2) The apps which use console API cannot be debugged with gdb. This
is because pseudo console is not activated since gdb uses
CreateProcess() rather than exec(). Even with this limitation,
attaching gdb to native apps, in which pseudo console is already
activated, works.
3) Typeahead key inputs are discarded while native console app is
executed. Simirally, typeahead key inputs while cygwin app is
executed are not inherited to native console app.
4) Code page cannot be changed by chcp.com. Acctually, chcp works
itself and changes code page of its own pseudo console. However,
since pseudo console is recreated for another process, it cannot
inherit the code page.
5) system_printf() does not work after stderr is closed. (Same with
cygwin 3.0.7)
6) Startup time of native console apps is about 3 times slower than
previous implemenation.
7) Pseudo console cannot be activated if it is already activated for
another process on same pty.
- Commit c4b060e3fe seems to be not
enough. Moreover, it does not work as expected at all in Win10
1809. This patch essentially reverts that commit and add another
fix. After all, the cause of the problem was a race issue in
switch_to_pcon_out flag. That is, this flag is set when native
app starts, however, it is delayed by wait_pcon_fwd(). Since the
flag is not set yet when less starts, the data which should go
into the output_handle accidentally goes into output_handle_cyg.
This patch fixes the problem more essentially for the cause of
the problem than previous one.
- The number of slaves attached to pseudo console is used only for
triggering redraw screen. Counting was not only needless, but also
did not work as expected. This patch removes the code for counting.
- PTY has a problem that the key input, which is typed during
windows native app is running, disappear when it returns to shell.
(Problem 3 in https://cygwin.com/ml/cygwin/2020-02/msg00007.html)
This is beacuse pty has two input pipes, one is for cygwin apps
and the other one is for native windows apps. The key input during
windows native program is running is sent to the second input pipe
while cygwin shell reads input from the first input pipe.
This patch realize transfering input data between these two pipes.
- After commit 6cc299f0e2, outputs of
cygwin programs which call both printf() and WriteConsole() are
frequently distorted. This patch fixes the issue.
- Though this rarely happens, sometimes the first printing of non-
cygwin process does not displayed correctly. To fix this issue,
the code for waiting for forwarding by master_fwd_thread is revised.
- Previously, pty cleared screen at startup for synchronization
between the real screen and console screen buffer for pseudo
console. With this patch, instead of clearing screen, the screen
is redrawn when the first native program is executed after pty
is created. In other words, synchronization is deferred until
the native app is executed. Moreover, this realizes excluding
$TERM dependent code.
- Since calling system __loadlocale() caused execution error,
PTY used its own NLS function. The cause of the error has been
found, the corresponding code has been rewritten using system
function.
- Previously, input and output pipes were switched together between
the traditional pty and the pseudo console. However, for example,
if stdin is redirected to another device, it is better to leave
input pipe traditional pty side even for non-cygwin program. This
patch realizes such behaviour.
- Pseudo console support introduced by commit
169d65a577 shows garbage ^[[H^[[J in
some of emacs screens. These screens do not handle ANSI escape
sequences. Therefore, clear screen is disabled on these screens.
- Support pseudo console in PTY. Pseudo console is a new feature
in Windows 10 1809, which provides console APIs on virtual
terminal. With this patch, native console applications can work
in PTYs such as mintty, ssh, gnu screen or tmux.
Revamp device parsing code. Introducing support for more partitions
into the shilka-generated parser has the unfortunate side-effect of
raising the size of the DLL by almost 2 Megs. Therefore we split out
the handling for /dev/sdXY devices into a tiny bit of hand-written
code.
While at it, remove some unused cruft from devices.* and generally
clean up the device class to provide access methods instead of direct
access to members.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
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>
* tty.h (class tty_min): Remove variable "write_error" to which any
errors are not currently set at anywhere.
(class tty): Add variable "column" for handling ONOCR.
* tty.cc (tty::init): Add initialization code for variable "column".
* fhandler.h (class fhandler_pty_master): Remove variable "need_nl"
which is not necessary any more. "need_nl" was needed by OPOST process
in fhandler_pty_master::process_slave_output().
(class fhandler_pty_common): Add function process_opost_output() for
handling post processing for OPOST in write process.
* fhandler_tty.cc (fhandler_pty_master::process_slave_output): Count
TIOCPKT control byte into length to be read in TIOCPKT mode. Move
post processing for OPOST to write process. Remove code related to
variable "write_error". Return with EIO error if slave is already
closed.
(fhandler_pty_master::fhandler_pty_master): Remove initialization
code for variable "need_nl".
(fhandler_pty_common::process_opost_output): Add this function for
handling of OPOST in write process. Add code to avoid blocking in
non-blocking mode when output is suspended by ^S.
(fhandler_pty_slave::write): Call fhandler_pty_common::
process_opost_output() instead of WriteFile(). Remove code related to
variable "write_error".
(fhandler_pty_master::doecho): Call fhandler_pty_common::
process_opost_output() instead of WriteFile().
* select.cc (peek_pipe): Remove code related to variable "need_nl".
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
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.
"create_selectable". Change return to DWORD.
(fhandler_pty_common::pipesize): New constant.
* fhandler_fifo.cc (fhandler_fifo::fhandler_fifo): Reflect create_selectable
name change.
* miscfuncs.cc (CreatePipeOverlapped): Ditto.
* pipe.cc (fhandler_pipe::create): Ditto.
(fhandler_pipe::create): Rename from the misnamed "create_selectable". Return
DWORD. Only set pipe size to default when it is passed in as zero.
* fhandler_tty.cc (fhandler_pty_master::setup): Ditto. Use
fhandler_pty_common::pipesize rather than a raw constant.
* tty.cc (tty::not_allocated): Ditto.
* sigproc.cc (sigproc_init): Use create_selectable to create the signal pipe to
get a more appropriate message based pipe.
an options argument for CreateNamedPipe/CreateFile. Change handle arguments to
expect pointers.
(fhandler_fifo::fifo_state): Delete.
(fhandler_fifo::dummy_client): Ditto.
(fhandler_fifo::open_nonserver): Ditto.
(fhandler_fifo::wait_state): Ditto.
(fhandler_fifo::raw_write): Ditto.
(fhandler_fifo::read_ready): New field.
(fhandler_fifo::write_ready): Ditto.
(fhandler_fifo::wait): Modify argument.
(fhandler_fifo::fifo_name): Add a new argument.
(fhandler_fifo::fixup_after_fork): New function.
* fhandler_fifo.cc (fhandler_fifo::fhandler_fifo): Remove initialization of
expunged elements. Initialize new handles to NULL.
(fhandler_fifo::open_nonserver): Delete.
(fnevent): New macro for creating a named event.
(fnpipe): New macro for creating a unique named pipe name.
(create_pipe): New macro for simplification of named pipe creation.
(fhandler_fifo::fifo_name): Use new argument when creating a shared name.
(fhandler_fifo::open): Rewrite. Use events to synchronize.
(pure_debug_printf): New macro, active only when DEBUGGING.
(fhandler_fifo::wait): Rewrite to wait for new fifo events which are supplied
as a parameter.
(fhandler_fifo::raw_read): Rewrite to use handle mechanism to detect
client-side disconnect.
(fhandler_fifo::raw_write): Delete.
(fhandler_fifo::close): Remove accommodations for expunged fields. Close event
handles.
(fhandler_fifo::dup): Remove accommodations for expunged fields. Duplicate
event handles.
(fhandler_fifo::fixup_after_fork): New function. Perform fixups on event
handles.
(fhandler_fifo::set_close_on_exec): Remove accommodations for expunged fields.
Set inheritance for new handle fields.
* miscfuncs.cc (CreatePipeOverlapped): Accommodate changes in
fhandler_pipe::create_selectable.
* tty.cc (tty::not_allocated): Ditto.
* pipe.cc (fhandler_pipe::create): Ditto.
(fhandler_pipe::create_selectable): Accept an extra open_mode argument. Pass
arguments by reference and allow opening one end of the pipe at a time.
* sys/strace.h (debug_only_printf): Define new macro which calls debug_printf
only when DEBUGGING is defined.
* devices.cc: Regenerate.
* dtable.cc: (fh_alloc): Preserve /dev/tty name when that's what we opened.
(build_fh_pc): Preserve any existing name.
* fhandler.cc (fhandler_base::open_with_arch): Ditto.
* fhandler_tty.cc (fhandler_pty_master::fhandler_pty_master): Force the name to
/dev/ptmx while preserving other pty master device information.
* path.h (cfree_maybe): New macro.
(path_conv::operator =): Free any allocated strings in target.
(path_conv::free_strings): Delete unused function.
* sigproc.cc (proc_terminate): Remove previous accommodation for execed
processes since it didn't have the desired effect. Change comment to a FIXME.
* spawn.cc (chExeced): Mark NO_COPY.
(exe_suffixes): Ditto.
logs easier. Throughout, change /dev/tty* to /dev/pty*. Throughout, add flags
argument to fhandler_*::dup methods.
* devices.in: Rename (temporarily?) /dev/ttyN to /dev/ptyN. Add /dev/ptymN
devices for pty masters.
* devices.cc: Regenerate.
* devices.h (MAX_CONSOLES): Set to max number supported by devices.in.
(fh_devices::FH_PTMX): Rename from FH_PTYM.
(device::operator int): Return by reference.
* dtable.cc (fh_alloc): Take pc as an argument rather than just the device.
This makes debugging easier since more information is available. Actually
implement handling for already-allocated pty master devices. Make different
decisions when generating fhandler for not-opened devices. Add kludge to deal
with opening /dev/tty.
(cnew_no_ctor): New macro.
(build_fh_pc): Make debugging output more verbose. Use new clone() fhandler
interface to duplicate archetypes. Reset last term opened.
(dtable::dup_worker): Use Use new clone() fhandler interface to duplicate
archetypes. Pass flags to child dup handler.
(dtable::dup3): Set O_NOCTTY flag if newfd is not stdin/stdout/stderr.
* fhandler.cc (fhandler_base::reset): Rename from operator =() and reduce
functionality and sense of copy direction.
(fhandler_base::open_with_arch): Use published interface to query io_handle().
Use new copyto() fhandler method to copy from/to found archetype.
* fhandler.h: Throughout, delete size(), add copyout, clone, and fhandler_*
(void *) methods.
(fhandler_base::reset): Rename from operator =().
(fhandler_termios::is_dev_tty): Delete.
(fhandler_termios): change "protected" region to "private".
(fhandler_termios::is_dev_tty): Delete.
(fhandler_termios): Rearrange protected/public.
(fhandler_termios::fhandler_termios): Remember last fhandler_termios "opened".
(fhandler_termios::~fhandler_termios): Forget last fhandler_termios opened.
(ioctl): Rename from ioctl_termios. Take a void * argument. Reflect argument
change in pinfo::set_ctty.
(fhandler_console::dup): Declare new function. Set ctty here if appropriate.
(fhandler_pty_master::from_master): Privatize.
(fhandler_pty_master::to_master): Ditto.
(fhandler_pty_master::dwProcessId): Ditto.
(fhandler_pty_master::fhandler_pty_master): Add an `int' argument.
(fhandler_pty_master::open_setup): Declare new function.
(fhandler_pty_master::~fhandler_pty_master): Declare new method.
(fhandler_nodevice): Remove commented out function declaration.
* fhandler_console.cc: Use get_ttyp() instead of tc() throughout.
(fhandler_console::dup): Define new function to set controlling ctty on dup, as
appropriate.
(fhandler_console::ioctl): Reflect ioctl_termios name change.
(fhandler_console::setup): Rename from get_tty_stuff.
(fhandler_console::open_setup): Reflect argument change in pinfo::set_ctty.
(fhandler_console::fhandler_console): Set _tc here.
* fhandler_termios.cc (handler_termios::ioctl): Rename. Take a void * arg like
other ioctl functions.
* fhandler_tty.cc (fhandler_pty_slave::dup): Call myself->set_ctty to
potentially reset the controlling terminal.
(fhandler_pty_slave::ioctl): Reflect name/arg change for ioctl_termios.
(fhandler_pty_slave::fhandler_pty_slave): Take a "unit" argument. Call setup()
here so that we will know the unit number of this fhandler as soon as possible.
Set the unit as appropriate.
(handler_pty_master::open): Move most stuff to constructor and open_setup.
(handler_pty_slave::open_setup): Reflect argument change in pinfo::set_ctty.
(handler_pty_master::open_setup): Define new function.
(fhandler_pty_master::cleanup): Clear handles as a flag that the destructor
does not have to do "close" operations.
(fhandler_pty_master::close): Ditto.
(fhandler_pty_master::~fhandler_pty_master): Define new method.
(fhandler_pty_master::ioctl): Reflect name/arg change for ioctl_termios.
(fhandler_pty_master::setup): Allocate tty here. Rely on handles being
returned from allocated test rather than opening them here. Avoid setting
_need_nl here since it is already zeroed in the constructor. Set up device
information with DEV_TTYM_MAJOR.
* path.h (path_conv &operator =): Take a const argument.
(path_conv::dup): Ditto.
(pathconv_arg::PC_OPEN): New enum.
(pathconv_arg::PC_CTTY): Ditto.
(path_types::PATH_CTTY): Ditto.
(path_types::PATH_OPEN): Ditto.
(path_conv::isopen): New method.
(path_conv::isctty_capable): Ditto.
* path.cc (path_conv::check): Set PATH_OPEN and PATH_CTTY as appropriate.
* pipe.cc (fhandler_pipe::open): Use copyto to copy pipe handle.
* syscall.cc (open): Reinstate fd > 2 check to disallow resetting ctty on
non-std* handles.
* tty.cc (tty_list::allocate): Pass out handles for allocated tty. use
`not_allocated' to find unallocated ttys. Avoid keeping the lock since the
allocation of the tty should be sufficient to prevent multiple access.
(tty::not_allocated): Clarify comment. Rename. Return handles when an unused
tty is found. Simply test for existing tty.
(tty::exists): Rewrite to use `not_allocated'.
* tty.h (NTTYS): Reset down to actual number supported by devices.in.
(tty::not_allocated): Declare new function.
(tty_list::allocate): Pass out read/write tty handles. Zero them when not
found.
* fhandler_proc.cc: Reflect name change from FH_PTYM -> FH_PTMX.
* pinfo.h (pinfo::set_ctty): Reduce/reorder arguments passed in.
* pinfo.cc (pinfo::set_ctty): Ditto. Just use tc() built into the passed-in
fhandler_termios pointer. Return true if ctty is assigned.
* syscalls.cc (open): Call build_fh_pc with PC_OPEN flag. Set PC_CTTY if
appropriate.
(stat_worker): Remove is_dev_tty () stuff.
Takashi Yano
Takashi Yano via Cygwin-patches
Corinna Vinschen
Christopher Faylor
Yaakov Selkowitz