Prior to commit b0717aae, path_conv::check had the following code:
if (strncmp (path, "\\\\.\\", 4))
{
/* Windows ignores trailing dots and spaces in the last path
component, and ignores exactly one trailing dot in inner
path components. */
char *tail = NULL;
[...]
if (!tail || tail == path)
/* nothing */;
else if (tail[-1] != '\\')
{
*tail = '\0';
[...]
}
Commit b0717aae0 intended to disable this code, but it inadvertently
disabled only part of it. In particular, the declaration of the local
tail variable was in the disabled code, but the following remained:
if (!tail || tail == path)
/* nothing */;
else if (tail[-1] != '\\')
{
*tail = '\0';
[...]
}
[A later commit removed the disabled code.]
The tail variable here points into a string different from path,
causing that string to be truncated under some circumstances. See
https://cygwin.com/ml/cygwin/2019-09/msg00001.html
for more details.
This commit fixes the problem by removing the leftover code
that was intended to be removed in b0717aae.
- The autoload feature is used rather than GetModuleHandle(),
GetProcAddress() for CreatePseudoConsole(), ResizePseudoConsole()
and ClosePseudoConsole().
- 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.
The CPU_SET macros defined in Cygwin's include/sys/cpuset.h must not
be visible in an application's namespace unless _GNU_SOURCE has been
#defined. Internally this means wrapping them in #if __GNU_VISIBLE.
- In non-canonical mode, cygwin console returned only one character
even if several keys are typed before read() called. This patch
fixes this behaviour.
- 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.
- If screen alternated while pseudo console switching, it sometimes
failed. This might happen when the output of the non-cygwin program
is piped to less. This patch fixes this issue.
- When the I/O pipe is switched to the pseudo console side, the
behaviour of Ctrl-C was unstable. This rarely happens, however,
for example, shell sometimes crashes by Ctrl-C in that situation.
Furthermore, Ctrl-C was ignored if output of non-cygwin program
is redirected to pipe. This patch fixes these issues.
The FACE Technical Standard, Edition 3.0 and later require the
definition of the subcommand SOCKCLOSE in <devctl.h>.
Reference: https://www.opengroup.org/face
- Forcibly attach to pseudo console in advance so that the error
messages by system_printf() are displayed to screen reliably.
This is needed when stdout is redirected to another pty. In this
case, process has two ptys opened. However, process can attach
to only one console. So it is necessary to change console attached.
- PTY with pseudo console support sitll has problem which potentially
cause state mismatch between state variable and real console state.
This patch fixes this issue.
- select() did not work correctly when both read and except are
polled simultaneously for the same fd and the r/w pipe is switched
to pseudo console side. This patch fixes this isseu.
- 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.
- Pseudo console support introduced by commit
169d65a577 sometimes cause random
crash or freeze by pressing ^C while cygwin and non-cygwin
processes are executed simultaneously in the same pty. This
patch is a workaround for this issue.
- API hook used for pseudo console support causes slow down.
This patch limits API hook to only program which is linked
with the corresponding APIs. Normal cygwin program is not
linked with such APIs (such as WriteFile, etc...) directly,
therefore, no slow down occurs. However, console access by
cygwin.dll itself cannot switch the r/w pipe to pseudo console
side. Therefore, the code to switch it forcely to pseudo
console side is added to smallprint.cc and strace.cc.
- Pseudo console support introduced by commit
169d65a577 has some bugs which
cause mismatch between state variables and real pseudo console
state regarding console attaching and r/w pipe switching. This
patch fixes this issue by redesigning the state management.
- PTY uses Win32 API hook for pseudo console suppot. The function
hook_api() is used for this purpose and defined in fhandler_tty.cc
previously. This patch moves it into hookapi.cc.
Commit 72ff9acad2 caused st_atime,
st_ctime, and st_mtime to be defined as macros. This collided with
use of these identifiers as field names in struct gdb_stat (which
represents the GDB RSP encoding of struct stat) in libgloss
semihosting support for nios2 and m68k. This patch renames the
affected fields of struct gdb_stat.
Signed-off-by: Sandra Loosemore <sandra@codesourcery.com>
- 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.
- revert previous fix which altered sys/stat.h
- fix libgloss/cris/gensyscalls to undef st_atime, st_mtime,
and st_ctime macros which cannot be used with new_stat structure
Rather than waiting for signalfd_select_wait in a thread, which is racy,
create a global event "my_pendingsigs_evt" which is set and reset by
wait_sig depending only on the fact if blocked signals are pending or not.
This in turn allows to WFMO on this event in select as soon as signalfds
are present in the read descriptor set. Select's peek and verify
will then check if one of the present signalfds is affected.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>