GitLab

 src/w32proc.c (reader_thread): Avoid passing NULL handles to
 SetEvent and WaitForSingleObject.

 src/w32proc.c (reader_thread): Do not index fd_info[] with negative
 values.
 (reader_thread): Exit when cp->status becomes STATUS_READ_ERROR
 after WaitForSingleObject returns normally.  This expedites reader
 thread shutdown when delete_child triggers it.
 (reap_subprocess): More accurate commentary for why we call
 delete_child only when cp->fd is negative.
 src/w32.c (sys_close): Do not call delete_child on a subprocess
 whose handle is not yet closed.  Instead, set its file descriptor
 to a negative value, so that reap_subprocess will call
 delete_child on that subprocess when its SIGCHLD arrives.  This
 avoids closing handles used for communications between sys_select
 and reader_thread, which doesn't give sys_select a chance to
 notice that the process exited and invoke the SIGCHLD handler for
 it.

 src/w32proc.c (new_child, delete_child, find_child_pid): For a
 subprocess, consider its slot being in use as long as its process
 handle (procinfo.hProcess) is not NULL.  This avoids reusing the
 slot when a new process is started immediately after killing
 another one, without waiting enough time for the first process to
 be reaped and resources allocated for it be orderly freed.
 Suggested by Fabrice Popineau <fabrice.popineau@supelec.fr>.

 src/w32.h (_child_process): New members input_file and
 pending_deletion.
 (register_child): First argument is now pid_t.
 (record_infile, record_pending_deletion): New prototypes.
 src/w32proc.c (new_child): Initialize input_file and
 pending_deletion members of the child.
 (delete_child): Delete the child's temporary input file, if any,
 that is pending deletion.
 (register_child): First argument is now pid_t.
 (record_infile, record_pending_deletion): New functions.
 (reap_subprocess): Fix a typo in DebPrint string.
 (sys_spawnve, sys_kill): Use pid_t for PID arguments.
 src/fileio.c (internal_delete_file): Return an int again: non-zero
 if delete-file succeeds, zero otherwise.
 src/lisp.h (internal_delete_file): Adjust prototype.
 src/callproc.c (Fcall_process): Don't overwrite infile with result
 of DECODE_FILE.
 [WINDOWSNT] If BUFFER is an integer, i.e. we are launching an
 asynchronous subprocess, record the name of the input file name,
 if any.
 (delete_temp_file) [WINDOWSNT]: If internal_delete_file fails to
 delete the file, record it as pending deletion when the subprocess
 exits.

 nt/inc/ms-w32.h (sys_unlink): Provide prototype.

Exceptions: do not assume SIGCONT, SIGSTOP, SIGTSTP, SIGTTIN,
SIGTTOU, SIGUSR1, SIGUSR2, as Microsoft platforms lack these.
* admin/CPP-DEFINES (SIGALRM, SIGCHLD, SIGHUP, SIGKILL, SIGPIPE, SIGQUIT):
Remove.
(SIGTRAP): Remove this one too, as config.h no longer defines it.
* admin/merge-gnulib (GNULIB_MODULES): Add sig2str.
* configure.ac (PTY_OPEN, PTY_TTY_NAME_SPRINTF):
Use SIGCHLD rather than SIGCLD.
* lib/sig2str.c, lib/sig2str.h, m4/sig2str.m4: New files, from gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/makefile.w32-in (GNULIBOBJS): Add $(BUILD)/sig2str.$(O).
* src/process.c [subprocesses]: Include <c-ctype.h>, <sig2str.h>.
(deleted_pid_list, Fdelete_process, create_process)
(record_child_status_change, handle_child_signal, deliver_child_signal)
(init_process_emacs, syms_of_process):
Assume SIGCHLD is defined.
(parse_signal): Remove.  All uses removed.
(abbr_to_signal): New static function.
(Fsignal_process): Use it to convert signal names to ints.
* src/sysdep.c (sys_suspend) [!DOS_NT]: Use kill (0, ...) rather than
kill (getpgrp (), ...).
(emacs_sigaction_init): Assume SIGCHLD is defined.
(init_signals): Assume SIGALRM, SIGCHLD, SIGHUP, SIGKILL,
SIGPIPE, and SIGQUIT are defined.  Do not worry about SIGCLD any more.
* src/syssignal.h (EMACS_KILLPG): Remove.
All uses replaced by 'kill' with a negative pid.
(SIGCHLD): Remove definition, as we now assume SIGCHLD.
* src/w32proc.c (sys_kill): Support negative pids compatibly with POSIX.

Fixes: debbugs:13026

 src/w32proc.c (waitpid): Avoid busy-waiting when called with WNOHANG
 if the child process is still running.  Instead, exit the wait
 loop and return zero.

Fixing this bug required some cleanup of the signal-handling code.
As a side effect, this change also fixes a longstanding rare race
condition whereby Emacs could mistakenly kill unrelated processes,
and it fixes a bug where a second C-g does not kill a recalcitrant
synchronous process in GNU/Linux and similar platforms.
The patch should also fix the last vestiges of Bug#9488,
a bug which has mostly been fixed on the trunk by other changes.
* callproc.c, process.h (synch_process_alive, synch_process_death)
(synch_process_termsig, sync_process_retcode):
Remove.  All uses removed, to simplify analysis and so that
less consing is done inside critical sections.
* callproc.c (call_process_exited): Remove.  All uses replaced
with !synch_process_pid.
* callproc.c (synch_process_pid, synch_process_fd): New static vars.
These take the role of what used to be in unwind-protect arg.
All uses changed.
(block_child_signal, unblock_child_signal):
New functions, to avoid races that could kill innocent-victim processes.
(call_process_kill, call_process_cleanup, Fcall_process): Use them.
(call_process_kill): Record killed processes as deleted, so that
zombies do not clutter up the system.  Do this inside a critical
section, to avoid a race that would allow the clutter.
(call_process_cleanup): Fix code so that the second C-g works again
on common platforms such as GNU/Linux.
(Fcall_process): Create the child process in a critical section,
to fix a race condition.  If creating an asynchronous process,
record it as deleted so that zombies do not clutter up the system.
Do unwind-protect for WINDOWSNT too, as that's simpler in the
light of these changes.  Omit unnecessary call to emacs_close
before failure, as the unwind-protect code does that.
* callproc.c (call_process_cleanup):
* w32proc.c (waitpid): Simplify now that synch_process_alive is gone.
* process.c (record_deleted_pid): New function, containing
code refactored out of Fdelete_process.
(Fdelete_process): Use it.
(process_status_retrieved): Remove.  All callers changed to use
child_status_change.
(record_child_status_change): Remove, folding its contents into ...
(handle_child_signal): ... this signal handler.  Now, this
function is purely a handler for SIGCHLD, and is not called after
a synchronous waitpid returns; the synchronous code is moved to
wait_for_termination.  There is no need to worry about reaping
more than one child now.
* sysdep.c (get_child_status, child_status_changed): New functions.
(wait_for_termination): Now takes int * status and bool
interruptible arguments, too.  Do not record child status change;
that's now the caller's responsibility.  All callers changed.
Reimplement in terms of get_child_status.
(wait_for_termination_1, interruptible_wait_for_termination):
Remove.  All callers changed to use wait_for_termination.
* syswait.h: Include <stdbool.h>, for bool.
(record_child_status_change, interruptible_wait_for_termination):
Remove decls.
(record_deleted_pid, child_status_changed): New decls.
(wait_for_termination): Adjust to API changes noted above.

Fixes: debbugs:12980

As reported by Harald Hanche-Olsen in
<http://lists.gnu.org/archive/html/emacs-devel/2012-11/msg00445.html>
the change introduces a further bug, of creating lots of zombie
processes in some cases.  Further work is needed to come up with a
better fix for Bug#8855.

This is a backport from the trunk, consisting of:

2012-11-17  Eli Zaretskii  <eliz@gnu.org>

* nt/inc/sys/wait.h: New file, with prototype of waitpid and
definitions of macros it needs.
* nt/inc/ms-w32.h (wait): Don't define, 'wait' is not used anymore.
(sys_wait): Remove prototype.
* nt/config.nt (HAVE_SYS_WAIT_H): Define to 1.
* src/w32proc.c (create_child): Don't clip the PID of the child
process to fit into an Emacs integer, as this is no longer a
restriction.
(waitpid): Rename from sys_wait.  Emulate a Posix 'waitpid' by
reaping only the process specified by PID argument, if that is
positive.  Use PID instead of dead_child to know which process to
reap.  Wait for the child to die only if WNOHANG is not in
OPTIONS.
(sys_select): Don't set dead_child.
* src/sysdep.c (wait_for_termination_1): Remove the WINDOWSNT portion,
as it is no longer needed.
* src/process.c (waitpid, WUNTRACED) [!WNOHANG]: Remove definitions,
no longer needed.
(record_child_status_change): Remove the setting of
record_at_most_one_child for the !WNOHANG case.

2012-11-03  Paul Eggert  <eggert@cs.ucla.edu>

Fix a race condition that causes Emacs to mess up glib (Bug#8855).
This is a backport from the trunk.
The symptom is a diagnostic "GLib-WARNING **: In call to
g_spawn_sync(), exit status of a child process was requested but
SIGCHLD action was set to SIG_IGN and ECHILD was received by
waitpid(), so exit status can't be returned."  The diagnostic
is partly wrong, as the SIGCHLD action is not set to SIG_IGN.
The real bug is a race condition between Emacs and glib: Emacs
does a waitpid (-1, ...) and reaps glib's subprocess by mistake,
so that glib can't find it.  Work around the bug by invoking
waitpid only on subprocesses that Emacs itself creates.
* src/process.c (create_process, record_child_status_change):
Don't use special value -1 in pid field, as the caller now must
know the pid rather than having the callee infer it.  The
inference was sometimes incorrect anyway, due to another race.
(create_process): Set new 'alive' member if child is created.
(process_status_retrieved): New function.
(record_child_status_change): Use it.
Accept negative 1st argument, which means to wait for the
processes that Emacs already knows about.  Move special-case code
for DOS_NT (which lacks WNOHANG) here, from caller.  Keep track of
processes that have already been waited for, by testing and
clearing new 'alive' member.
(CAN_HANDLE_MULTIPLE_CHILDREN): Remove, as record_child_status_change
now does this internally.
(handle_child_signal): Let record_child_status_change do all
the work, since we do not want to reap all exited child processes,
only the child processes that Emacs itself created.
* src/process.h (Lisp_Process): New boolean member 'alive'.

 nt/inc/sys/wait.h: New file, with prototype of waitpid and
 definitions of macros it needs.
 nt/inc/ms-w32.h (wait): Don't define, 'wait' is not used anymore.
 (sys_wait): Remove prototype.
 nt/config.nt (HAVE_SYS_WAIT_H): Define to 1.

 src/w32proc.c (create_child): Don't clip the PID of the child
 process to fit into an Emacs integer, as this is no longer a
 restriction.
 (waitpid): Rename from sys_wait.  Emulate a Posix 'waitpid' by
 reaping only the process specified by PID argument, if that is
 positive.  Use PID instead of dead_child to know which process to
 reap.  Wait for the child to die only if WNOHANG is not in
 OPTIONS.
 (sys_select): Don't set dead_child.
 src/sysdep.c (wait_for_termination_1): Remove the WINDOWSNT portion,
 as it is no longer needed.
 src/process.c (waitpid, WUNTRACED) [!WNOHANG]: Remove definitions,
 no longer needed.
 (record_child_status_change): Remove the setting of
 record_at_most_one_child for the !WNOHANG case.

 src/w32proc.c (timer_loop): Make sure SuspendThread and ResumeThread
 use the same value of thread handle.
 (start_timer_thread): If the timer thread exited (due to error),
 clean up by closing the two handles it used.  Duplicate the caller
 thread's handle here, so it gets duplicated only once, when
 launching the timer thread.  Set priority of the timer thread, not
 the caller thread.
 (getitimer): Don't duplicate the caller thread's handle here.

This removes code that has been obsolete since around 1990.
* admin/CPP-DEFINES (HAVE_SETPGID, HAVE_SETSID, SETPGRP_RELEASES_CTTY):
Remove; obsolete.
* configure.ac (setpgid, setsid): Assume their existence.
(AC_FUNC_GETPGRP, SETPGRP_RELEASES_CTTY): Remove; obsolete.
* src/callproc.c (Fcall_process):
* src/emacs.c (main):
* src/process.c (create_process):
* src/term.c (dissociate_if_controlling_tty):
Assume setsid exists.
* src/callproc.c (child_setup): Assume setpgid exists and behaves as
per POSIX.1-1988 or later.
* src/conf_post.h (setpgid) [!HAVE_SETPGID]: Remove.
* src/emacs.c (shut_down_emacs):
* src/sysdep.c (sys_suspend, init_foreground_group):
Assume getpgrp behaves as per POSIX.1-1998 or later.
* src/msdos.c (setpgrp): Remove.
(tcgetpgrp, setpgid, setsid): New functions.
* src/systty.h (EMACS_GETPGRP): Remove.  All callers now use getpgrp.
* src/term.c (no_controlling_tty): Remove; unused.
* src/w32proc.c (setpgrp): Remove.
(setsid, tcgetpgrp): New functions.

Fixes: debbugs:12800

 src/w32proc.c (getpgrp, setpgid): New functions.

 nt/inc/unistd.h (setpgid, getpgrp): Provide prototypes.
 nt/config.nt (GETPGRP_VOID): Define to 1.

 src/w32proc.c (TIMER_TICKS_PER_SEC): New macro.
 (timer_loop, getitimer, setitimer): Use it instead of
 CLOCKS_PER_SEC, which is no longer pertinent, since we don't use
 'clock'.
 (w32_get_timer_time): Use 10*TIMER_TICKS_PER_SEC instead of a
 literal 10000.

 src/w32proc.c (sys_spawnve): Avoid compiler warning about format mismatch.
 (timer_loop): Remove unused variable.

 Avoid overflow in w32 implementation of interval timers.  When
 possible, for ITIMER_PROF count only times the main thread
 actually executes.

 src/w32proc.c <struct itimer_data>: 'expire' and 'reload' are now
 ULONGLONG types.  Likewise for all the other data which was
 previously clock_t.
 (GetThreadTimes_Proc): New typedef.
 (w32_get_timer_time): New function, returns a suitable time value
 for the timer.
 (timer_loop): Enter critical section when accessing ULONGLONG
 values of the itimer_data struct, as these accesses are no longer
 atomic.  Call 'w32_get_timer_time' instead of 'clock'.
 (init_timers): Initialize s_pfn_Get_Thread_Times.
 (start_timer_thread): Don't assign itimer->caller_thread here.
 (getitimer): Assign itimer->caller_thread here.
 (setitimer): Always call getitimer to get the value of ticks_now.

 src/makefile.w32-in ($(BLD)/w32.$(O)): 
 ($(BLD)/vm-limit.$(O)): 
 ($(BLD)/term.$(O)): 
 ($(BLD)/unexw32.$(O)): 
 ($(BLD)/fileio.$(O)): 
 ($(BLD)/dispnew.$(O)): Update dependencies.
 src/w32term.h (w32_initialize_display_info, initialize_w32_display):
 Add prototypes.
 src/w32proc.c: Include ctype.h.
 src/w32.h (init_environment, check_windows_init_file)
 (syms_of_ntproc, syms_of_ntterm, dostounix_filename)
 (unixtodos_filename, init_winsock, srandom, random, sys_pipe)
 (set_process_dir, sys_spawnve, register_child, sys_sleep, getwd)
 (sys_link): Add prototypes.
 src/w32.c: Include w32select.h.
 (sys_access, e_malloc, sys_select): Add prototypes.
 (emacs_gnutls_pull): 'timeout' is now EMACS_TIME, not struct timeval.
 src/vm-limit.c [WINDOWSNT]: Include w32heap.h.
 src/unexw32.c: Include lisp.h and w32.h.
 src/term.c [WINDOWSNT]: Include w32term.h.
 src/process.c [WINDOWSNT]: Add prototype of sys_select.
 src/fileio.c [WINDOWSNT]: Include w32.h.
 src/dispnew.c [WINDOWSNT]: Include w32.h.

 nt/inc/pwd.h (getuid, geteuid): Add prototypes.
 nt/inc/ms-w32.h (sys_wait, _getpid, gmtgime_r, localtime_r)
 (signal_handler, sys_signal, sigemptyset, sigfillset, sigprocmask)
 (pthread_sigmask, sigismember, setpgrp, sigaction, alarm)
 (sys_kill, getpagesize): Add prototypes for emulated functions.
 nt/inc/grp.h (getgid, getegid): Add prototypes.
 nt/gmake.defs (DEBUG_CFLAGS) [NOOPT]: Add -std=gnu99.
 nt/configure.bat (chkapiN): Avoid compiler warning in junk.c when
 compiling with -std=gnu99.
 nt/config.nt (CHECK_LISP_OBJECT_TYPE): Don't undef, so that it
 could be used via --cflags switch to configure.bat.

doesn't have focus.

 src/w32proc.c (stop_timer_thread): Fix declaration of 'err'.

 src/w32proc.c (sys_wait): Declare 'signame' 'const char *', to be
 consistent with the change in return value of 'safe_strsignal'.

 nt/preprep.c (RVA_TO_PTR): Cast the result to 'void *', to avoid
 compiler warnings when using the value.

 src/w32proc.c (timer_loop): Fix code that waits for timer
 expiration, to avoid high CPU usage.

 src/w32proc.c (alarm) [HAVE_SETITIMER]: Be more conformant to the expected
 return results.
 [!HAVE_SETITIMER]: Behave as the previous version that didn't
 support timers.

 src/w32proc.c <disable_itimers>: New static flag.
 (init_timers): Initialize it to zero, after creating the critical
 sections used by the timer threads.
 (term_timers): Set to 1 before deleting the critical sections.
 (getitimer, setitimer): If disable_itimers is non-zero, return an
 error indication without doing anything.  Reported by Fabrice
 Popineau <fabrice.popineau@supelec.fr> as part of bug#12544.

 src/w32term.h (SCROLL_BAR_PACK, SCROLL_BAR_UNPACK): Define for x64.
 (SET_SCROLL_BAR_W32_WINDOW): Cast ID to intptr_t, for
 compatibility with x64.
 src/w32term.c (w32_draw_underwave): Don't use GCC extensions for
 defining an XRectangle structure.
 src/w32proc.c (RVA_TO_PTR, w32_executable_type): Fix pointer
 arithmetics for compatibility with x64.
 src/w32menu.c (add_menu_item): Use UINT_PTR instead of UINT, for
 compatibility with x64.
 src/w32heap.h: Adjust prototypes and declarations.
 src/w32heap.c (RVA_TO_PTR, allocate_heap, sbrk, init_heap)
 (round_heap): Use DWORD_PTR, ptrdiff_t and size_t instead of
 DWORD, long, and unsigned long, for compatibility with x64.
 (allocate_heap) [_WIN64]: Reserve 32GB of memory.
 (sbrk): Argument is now of type ptrdiff_t.
 src/w32fns.c (HMONITOR): Condition declaration on _WIN32_WINNT being
 less than 0x0500.
 (w32_msg_pump): Use WPARAM type for 'result'.
 src/w32.c (init_environment, get_emacs_configuration): Support AMD64
 architecture.
 (init_ntproc): Cast arguments of _open_osfhandle to intptr_t, for
 compatibility with x64.
 src/vm-limit.c (lim_data): Now size_t.
 (check_memory_limits): Adjust prototypes of real_morecore and
 __morecore to receive argument of type ptrdiff_t.  Use size_t for
 five_percent and data_size.
 src/unexw32.c: Use DWORD_PTR instead of DWORD for file-scope
 variables, for compatibility with x64.
 (rva_to_section, offset_to_section, relocate_offset)
 (OFFSET_TO_RVA, RVA_TO_OFFSET, RVA_TO_SECTION_OFFSET)
 (PTR_TO_RVA, RVA_TO_PTR, OFFSET_TO_PTR, get_section_info)
 (copy_executable_and_dump_data): Use DWORD_PTR instead of DWORD
 for compatibility with x64.
 src/sysdep.c (STDERR_FILENO): Define if not already defined.
 src/ralloc.c (real_morecore): Argument type is now ptrdiff_t.
 (__morecore): Argument type is now ptrdiff_t.
 (ROUNDUP, MEM_ROUNDUP): Use size_t instead of 'unsigned long'.
 (relinquish): Use ptrdiff_t type for 'excess'.
 (r_alloc_sbrk): Argument type is now ptrdiff_t.
 src/makefile.w32-in (HEAPSIZE): Get value from EMACS_HEAPSIZE.
 (bootstrap-temacs-CMD, bootstrap-temacs-SH): Use $(EMACS_PURESIZE)
 instead of a literal number.
 src/gmalloc.c [WINDOWSNT]: Include w32heap.h.
 (min): Define only if not already defined.
 src/frame.c (x_report_frame_params): Use EMACS_UINT for the return
 value of FRAME_X_WINDOW, to fit a 64-bit pointer on 64-bit Windows
 hosts.
 src/image.c (x_bitmap_pixmap): Return ptrdiff_t, not int, since
 'bitmaps' is a pointer.
 src/dispextern.h (x_bitmap_pixmap): Adjust prototype.
 src/alloc.c (gdb_make_enums_visible): Now conditional on __GNUC__.

 nt/makefile.w32-in ($(TRES)): Use $(EMACS_MANIFEST).
 nt/inc/sys/socket.h: Don't map Winsock error codes to standard ones
 that are already defined.
 nt/inc/ms-w32.h (EMACS_INT, EMACS_UINT, EMACS_INT_MAX, PRIuMAX)
 (pI, _INTPTR) [_MSC_VER]: Fix definitions for MSVC.
 [_MSC_VER]: Add pragmas to suppress some MSVC warnings.
 nt/preprep.c (pfnCheckSumMappedFile, rva_to_section)
 (offset_to_section, relocate_offset, OFFSET_TO_RVA)
 (RVA_TO_OFFSET, RVA_TO_SECTION_OFFSET, PTR_TO_RVA)
 (OFFSET_TO_PTR, ROUND_UP, ROUND_DOWN)
 (copy_executable_and_move_sections, ADJUST_IMPORT_RVA, main): Use
 DWORD_PTR instead of DWORD for compatibility with x64.
 nt/nmake.defs: Support AMD64.
 (EMACS_HEAPSIZE, EMACS_PURESIZE, EMACS_MANIFEST): New macros.
 nt/gmake.defs: (EMACS_HEAPSIZE, EMACS_PURESIZE, EMACS_MANIFEST):
 New macros.
 nt/addsection.c (pfnCheckSumMappedFile, rva_to_section)
 (offset_to_section, relocate_offset, OFFSET_TO_RVA)
 (RVA_TO_OFFSET, RVA_TO_SECTION_OFFSET, PTR_TO_RVA)
 (OFFSET_TO_PTR, ROUND_UP, ROUND_DOWN)
 (copy_executable_and_add_section, main): Use DWORD_PTR instead of
 DWORD, for compatibility with x64.
 nt/emacs-x64.manifest: New file.
 nt/emacs-x86.manifest: Renamed from emacs.manifest.

 lib-src/ntlib.c (gettimeofday): Copy from src/w32.c.  lib/gettime. 
 needs this function.

 src/w32proc.c (sig_mask, crit_sig): New static variables.
 (sys_signal): Support SIGALRM and SIGPROF.
 (sigemptyset, sigaddset, sigfillset, sigprocmask)
 (pthread_sigmask, setpgrp): Moved here from w32.c.  sigaddset,
 sigfillset, and sigprocmask are no longer no-ops.
 (sigismember): New function.
 (struct itimer_data): New definition.
 (ticks_now, real_itimer, prof_itimer, clocks_min, crit_real)
 (crit_prof): New static variables.
 (MAX_SINGLE_SLEEP): New definition.
 (timer_loop, stop_timer_thread, term_timers, init_timers)
 (start_timer_thread, getitimer, setitimer): New functions.
 (alarm): No longer a no-op, calls setitimer.
 src/w32.c (term_ntproc): Call term_timers.
 (init_ntproc): Make sure all signals are unblocked at startup, to
 erase any traces of dumping.  Call init_timers.
 src/w32fns.c (hourglass_timer, HOURGLASS_ID): Remove.
 Windows-specific code to display the hourglass mouse pointer is no
 longer used.
 (w32_wnd_proc): Remove code that handled the WM_TIMER message due
 to hourglass timer expiration.
 (start_hourglass, cancel_hourglass, DEFAULT_HOURGLASS_DELAY):
 Remove, no longer used.
 (w32_note_current_window, show_hourglass, hide_hourglass): New
 functions, in support of hourglass cursor display similar to other
 window systems.
 (syms_of_w32fns): Don't initialize hourglass_timer.
 src/xdisp.c (start_hourglass, cancel_hourglass): Now used on
 WINDOWSNT as well.
 (start_hourglass) [WINDOWSNT]: Call w32_note_current_window.
 src/w32.h (init_timers, term_timers): Add prototypes.

 nt/inc/sys/time.h (ITIMER_REAL, ITIMER_PROF): Define.
 (struct itimerval): Define.
 (getitimer, setitimer): Add prototypes.
 nt/inc/ms-w32.h <sigset_t> [_MSVC_VER]: Make the typedef consistent
 with MinGW.
 (SA_RESTART, SIGPROF): Define.
 nt/config.nt (HAVE_SETITIMER): Define to 1.

 src/w32proc.c (sys_signal): Handle all signals defined by the
 MS-Windows runtime, not just SIGCHLD.  Actually install the signal
 handlers for signals supported by Windows.  Don't override
 term_ntproc as the handler for SIGABRT.
 (sigaction): Rewrite to call sys_signal instead of duplicating its
 code.
 (sys_kill): Improve commentary.
 src/w32.c (term_ntproc): Accept (and ignore) one argument, for
 consistency with a signature of a signal handler.  All callers
 changed.
 (init_ntproc): Accept an argument DUMPING.  If dumping, don't
 install term_ntproc as a signal handler for SIGABRT, as that
 should be done by the dumped Emacs.
 src/w32.h (init_ntproc, term_ntproc): Adjust prototypes.
 src/w32select.c (term_w32select): Protect against repeated
 invocation by setting clipboard_owner to NULL after calling
 DestroyWindow.
 src/emacs.c (shut_down_emacs, main): Adapt the calls to init_ntproc
 and term_ntproc to their modified signatures.

 src/.gdbinit: Set breakpoint on terminate_due_to_signal, not on
 fatal_error_backtrace.
 src/w32proc.c (sys_kill): Undo last change: don't do anything when
 invoked to deliver SIGABRT to our own process.  This is now
 handled by emacs_raise.

 nt/inc/ms-w32.h (emacs_raise): Redefine to invoke emacs_abort.

Fixes: debbugs:12471

Here, we use the generic window-system configuration system we just
implemented to support the w32 window-system in the mainline build
under Cygwin.  (Previously, the w32 window system could only be
compiled as part of the NT-native Emacs build process.)

The changes in this patch need to be applied atomically in order to
avoid breaking Emacs.  The changes include:

  - Changes throughout the Lisp and C code to not assume that
      NT Emacs and the w32 window system are synonymous.

  - Wiring up the regular select(2) event loop to Windows messages

  - Cleaning up the w32 drag-and-drop receiving code.

  - Exposing Cygwin path conversion functions to elisp.

  - Unicode file dialog support when compiling for Cygwin.

  - Splitting the w32 term lisp initialization code into code
    applicable to any w32 window-system and code specific to
    system-type windows-nt.

  - Integrating the old and new w32 code into the build system.

Fix MS-Windows build broken by 2012-09-15T07:06:56Z!eggert@cs.ucla.edu, completing fix for bug #12446.

 src/w32xfns.c:
 src/w32uniscribe.c:
 src/w32term.c:
 src/w32select.c:
 src/w32reg.c:
 src/w32proc.c:
 src/w32menu.c:
 src/w32inevt.c:
 src/w32heap.c:
 src/w32font.c:
 src/w32fns.c:
 src/w32console.c:
 src/w32.c:
 src/w16select.c: Remove inclusion of setjmp.h, as it is now included
 by lisp.h.  This completes removal of setjmp.h inclusion
 erroneously announced in the previous commit.
 src/lisp.h [!HAVE__SETJMP, !HAVE_SIGSETJMP]: Make the commentary
 more accurate.
 src/image.c (_setjmp) [!HAVE__SETJMP]: Define only if 'setjmp' is
 not defined as a macro.  The latter happens on MS-Windows.

 src/w32proc.c (sys_kill): If PID is our process ID and the signal is
 SIGABRT, call emacs_abort.  Avoids silently exiting upon assertion
 violation.  (Bug#12426)

 src/w32proc.c (sigaction): New function, emulates Posix 'sigaction'.
 src/w32.c (sigemptyset): Empty the set.
 (sigsetmask, sigmask, sigblock, sigunblock): Remove unused functions.

 nt/inc/ms-w32.h (struct sigaction): Declare sa_handler __cdecl.

Fixes: debbugs:12327

Do not try to redefine the 'abort' function.  Instead, redo
the code so that it calls 'emacs_abort' rather than 'abort'.
This removes the need for the NO_ABORT configure-time macro
and makes it easier to change the abort code to do a backtrace.
* configure.ac (NO_ABRT): Remove.
* admin/CPP-DEFINES (NO_ABORT): Remove.
* nt/inc/ms-w32.h (w32_abort) [HAVE_NTGUI]: Remove.
* src/.gdbinit: Just stop at emacs_abort, not at w32_abort or abort.
* src/emacs.c (abort) [!DOS_NT && !NO_ABORT]:
Remove; sysdep.c's emacs_abort now takes its place.
* src/lisp.h (emacs_abort): New decl.  All calls from Emacs code to
'abort' changed to use 'emacs_abort'.
* src/msdos.c (dos_abort) [defined abort]: Remove; not used.
(abort) [!defined abort]: Rename to ...
(emacs_abort): ... new name.
* src/sysdep.c (emacs_abort) [!HAVE_NTGUI]: New function, taking
the place of the old 'abort' in emacs.c.
* src/w32.c, src/w32fns.c (abort): Do not #undef.
* src/w32.c (emacs_abort): Rename from w32_abort.