GitLab

* emacs.c (close_output_streams): Use strerror, not emacs_strerror,
as we can't assume that emacs_strerror is initialized, and strerror
is good enough here.
(main): Invoke atexit earlier, to catch earlier instances of
sending data to stdout and exiting, e.g., "emacs --version >/dev/full".

Fixes: debbugs:9574

* admin/merge-gnulib (GNULIB_MODULES): Add close-stream.
* lib/close-stream.c, lib/close-stream.h, lib/fpending.c
* lib/fpending.h, m4/close-stream.m4, m4/fpending.m4:
New files, from gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* src/emacs.c: Include <close-stream.h>.
(close_output_streams): New function.
(main): Pass it to atexit, so that Emacs closes stdout and stderr
and handles errors appropriately.
(Fkill_emacs): Don't worry about flushing, as close_output_stream
does that now.

Fixes: debbugs:9574

* callproc.c (setpgrp): Remove macro, as we now use setpgid
and it is configured in conf_post.h.
(Fcall_process): Don't invoke both setsid and setpgid; the former
is enough, if it exists.
* callproc.c (Fcall_process, child_setup):
* process.c (create_process): Use setpgid.
* conf_post.h (setpgid) [!HAVE_SETPGID]: New macro, which substitutes
for the real thing.
* dispnew.c (init_display): Initialize the foreground group
if we are running a tty display.
* emacs.c (main): Do not worry about setpgrp; init_display does it now.
* lisp.h (init_foreground_group): New decl.
* sysdep.c (inherited_pgroup): New static var.
(init_foreground_group, tcsetpgrp_without_stopping)
(narrow_foreground_group, widen_foreground_group): New functions.
(init_sys_modes): Narrow foreground group.
(reset_sys_modes): Widen foreground group.

Fixes: debbugs:12697

* emacs.c (shut_down_emacs) [!DOS_NT]:
* sysdep.c (sys_suspend) [SIGTSTP && !MSDOS]:
* term.c (dissociate_if_controlling_tty) [!DOS_NT]:
Use pid_t, not int, to store process IDs, as 'int'
is not wide enough on a few platforms (e.g., AIX and IRIX).

Space before paren, avoid overparenthesization, etc.

 src/emacs.c (DAEMON_MUST_EXEC) [HAVE_NTGUI]: Define this only on Cygwin.

A signal can arrive in the middle of a malloc, and Emacs's signal
handler can invoke strsignal, which can invoke malloc, which is
not portable.  This race condition bug makes Emacs hang on GNU/Linux.
Fix it by altering the signal handler so that it does not invoke
strsignal.
* emacs.c (shut_down_emacs): Use safe_strsignal, not strsignal.
* process.c (status_message): Use const pointer, in case strsignal
is #defined to safe_strsignal.
* sysdep.c (sys_siglist, init_signals): Always define and
initialize a substitute sys_siglist if the system does not define
one, even if HAVE_STRSIGNAL.
(safe_strsignal): Rename from strsignal.  Always define,
using sys_siglist.  Return a const pointer.
* syssignal.h (safe_strsignal): New decl.
(strsignal) [!HAVE_STRSIGNAL]: Define in terms of safe_strsignal.

 src/emacs.c: Move the inclusion of TERM_HEADER after including
 windows.h on WINDOWSNT.  This avoids compilation problems with
 MSVC.

 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/lisp.h (reset_image_types): Declare.
[WINDOWSNT] (Vlibrary_cache): Declare.

* src/image.c (reset_image_types): New function.

* src/emacs.c [WINDOWSNT] (Vlibrary_cache): Move from w32.c.
(syms_of_emacs) [WINDOWSNT] <Vlibrary_cache>: Initialize and staticpro.
(Fdump_emacs): Reset Vlibrary_cache and image_types.

* src/w32.c (Vlibrary_cache): Do not define; moved to emacs.c
(globals_of_w32) <Vlibrary_cache>: Do not initialize.

* src/w32.h (Vlibrary_cache): Do not declare.

 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.

Problem reported by Dani Moncayo in
<http://lists.gnu.org/archive/html/emacs-devel/2012-09/msg00557.html>.
* alloc.c (die):
* sysdep.c (emacs_abort): Do not reset signal handler.
* emacs.c (terminate_due_to_signal): Reset signal handler here.
* sysdep.c (init_signals): Do not use SA_NODEFER.  It wasn't
wanted even on POSIXish hosts, and it doesn't work on Windows.

* nt/inc/ms-w32.h (emacs_raise): New macro.
* src/alloc.c (die):
* src/sysdep.c (emacs_abort) [HAVE_NTGUI]:
Avoid recursive loop if there's a fatal error in the function itself.
* src/atimer.c (pending_atimers):
* src/blockinput.h: Don't include "atimer.h"; no longer needed.
(interrupt_input_pending): Remove.  All uses removed.
pending_signals now counts both atimers and ordinary interrupts.
This is less racy than having three separate pending-signal flags.
(block_input, unblock_input, totally_unblock_input, unblock_input_to)
(input_blocked_p):
Rename from their upper-case counterparts BLOCK_INPUT,
UNBLOCK_INPUT, TOTALLY_UNBLOCK_INPUT, UNBLOCK_INPUT_TO,
INPUT_BLOCKED_P, and turn into functions.  All uses changed.
This makes it easier to access volatile variables more accurately.
(BLOCK_INPUT_RESIGNAL): Remove.  All uses replaced by unblock_input ().
(input_blocked_p): Prefer this to 'interrupt_input_blocked', as
that's more reliable if the code is buggy and sets
interrupt_input_blocked to a negative value.  All uses changed.
* src/atimer.c (deliver_alarm_signal):
Remove.  No need to deliver this to the parent; any thread can
handle this signal now.  All uses replaced by underlying handler.
* src/atimer.c (turn_on_atimers):
* src/dispnew.c (handle_window_change_signal):
* src/emacs.c (handle_danger_signal):
* src/keyboard.c (kbd_buffer_get_event):
Don't reestablish signal handler; not needed with sigaction.
* src/blockinput.h (UNBLOCK_INPUT_TO, TOTALLY_UNBLOCK_INPUT)
(UNBLOCK_INPUT_TO):
Rework to avoid unnecessary accesses to volatile variables.
(UNBLOCK_INPUT_TO): Now a function.
(totally_unblock_input, unblock_input): New decls.
* src/data.c (handle_arith_signal, deliver_arith_signal): Move to sysdep.c
(init_data): Remove.  Necessary stuff now done in init_signal.
* src/emacs.c, src/xdisp.c: Include "atimer.h", since we invoke atimer functions.
* src/emacs.c (handle_fatal_signal, deliver_fatal_signal): Move to sysdep.c.
(fatal_error_code): Remove; no longer needed.
(terminate_due_to_signal): Rename from fatal_error_backtrace, since
it doesn't always backtrace.  All uses changed.  No need to reset
signal to default, since sigaction and/or die does that for us now.
Use emacs_raise (FOO), not kill (getpid (), FOO).
(main): Check more-accurately whether we're dumping.
Move fatal-error setup to sysdep.c
* src/floatfns.c: Do not include "syssignal.h"; no longer needed.
* src/gtkutil.c (xg_get_file_name, xg_get_font):
Remove no-longer-needed signal-mask manipulation.
* src/keyboard.c, src/process.c (POLL_FOR_INPUT):
Don't depend on USE_ASYNC_EVENTS, a symbol that is never defined.
* src/keyboard.c (read_avail_input): Remove.
All uses replaced by gobble_input.
(Ftop_level): Use TOTALLY_UNBLOCK_INPUT rather than open code.
(kbd_buffer_store_event_hold, gobble_input):
(record_asynch_buffer_change) [USABLE_SIGIO]:
(store_user_signal_events):
No need to mess with signal mask.
(gobble_input): If blocking input and there are terminals, simply
set pending_signals to 1 and return.  All hooks changed to not
worry about whether input is blocked.
(process_pending_signals): Clear pending_signals before processing
them, in case a signal comes in while we're processing.
By convention callers now test pending_signals before calling us.
(UNBLOCK_INPUT_TO, unblock_input, totally_unblock_input):
New functions, to support changes to blockinput.h.
(handle_input_available_signal): Now extern.
(reinvoke_input_signal): Remove.  All uses replaced by
handle_async_input.
(quit_count): Now volatile, since a signal handler uses it.
(handle_interrupt): Now takes bool IN_SIGNAL_HANDLER as arg.  All
callers changed.  Block SIGINT only if not already blocked.
Clear sigmask reliably, even if Fsignal returns, which it can.
Omit unnecessary accesses to volatile var.
(quit_throw_to_read_char): No need to restore sigmask.
* src/keyboard.c (gobble_input, handle_user_signal):
* src/process.c (wait_reading_process_output):
Call signal-handling code rather than killing ourselves.
* src/lisp.h: Include <float.h>, for...
(IEEE_FLOATING_POINT): New macro, moved here to avoid duplication.
(pending_signals): Now volatile.
(syms_of_data): Now const if IEEE floating point.
(handle_input_available_signal) [USABLE_SIGIO]:
(terminate_due_to_signal, record_child_status_change): New decls.
* src/process.c (create_process): Avoid disaster if memory is exhausted
while we're processing a vfork, by tightening the critical section
around the vfork.
(send_process_frame, process_sent_to, handle_pipe_signal)
(deliver_pipe_signal): Remove.  No longer needed, as Emacs now
ignores SIGPIPE.
(send_process): No need for setjmp/longjmp any more, since the
SIGPIPE stuff is now gone.  Instead, report an error if errno
is EPIPE.
(record_child_status_change): Now extern.  PID and W are now args.
Return void, not bool.  All callers changed.
* src/sysdep.c (wait_debugging) [(BSD_SYSTEM || HPUX) && !defined (__GNU__)]:
Remove.  All uses removed.  This bug should be fixed now in a
different way.
(wait_for_termination_1): Use waitpid rather than sigsuspend,
and record the child status change directly.  This avoids the
need to futz with the signal mask.
(process_fatal_action): Move here from emacs.c.
(emacs_sigaction_flags): New function, containing
much of what used to be in emacs_sigaction_init.
(emacs_sigaction_init): Use it.  Block nonfatal system signals that are
caught by emacs, to make races less likely.
(deliver_process_signal): Rename from handle_on_main_thread.
All uses changed.
(BACKTRACE_LIMIT_MAX): Now at top level.
(thread_backtrace_buffer, threadback_backtrace_pointers):
New static vars.
(deliver_thread_signal, deliver_fatal_thread_signal):
New functions, for more-accurate delivery of thread-specific signals.
(handle_fatal_signal, deliver_fatal_signal): Move here from emacs.c.
(deliver_arith_signal): Handle in this thread, not
in the main thread, since it's triggered by this thread.
(maybe_fatal_sig): New function.
(init_signals): New arg DUMPING so that we can be more accurate
about whether we're dumping.  Caller changed.
Treat thread-specific signals differently from process-general signals.
Block all signals while handling fatal error; that's safer.
xsignal from SIGFPE only on non-IEEE hosts, treating it as fatal
on IEEE hosts.
When batch, ignore SIGHUP, SIGINT, SIGTERM if they were already ignored.
Ignore SIGPIPE unless batch.
(emacs_backtrace): Output backtrace for the appropriate thread,
which is not necessarily the main thread.
* src/syssignal.h: Include <stdbool.h>.
(emacs_raise): New macro.
* src/xterm.c (x_connection_signal): Remove; no longer needed
now that we use sigaction.
(x_connection_closed): No need to mess with sigmask now.
(x_initialize): No need to reset SIGPIPE handler here, since
init_signals does this for us now.

Fixes: debbugs:12471

or that fprintf is async-signal-safe.  POSIX doesn't require
either assumption.

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.

* configure.ac (copyright): New output variable.
(COPYRIGHT): New AC_DEFINE.

* admin/admin.el (set-copyright): No more need to set copyrights for
nextstep, or .c files.  Add configure.ac and config.nt.

* lib-src/ebrowse.c (version):
* lib-src/etags.c (print_version): Use COPYRIGHT.

* nextstep/templates/Info-gnustep.plist.in:
* nextstep/templates/InfoPlist.strings.in:
* nextstep/templates/Info.plist.in: Let configure set copyright.

* nt/config.nt (COPYRIGHT): New.

* src/emacs.c: Use COPYRIGHT.

When auditing signal-handling in preparation for cleaning it up,
I found that SYNC_INPUT has race conditions and would be a real
pain to fix.  Since it's an undocumented and deprecated
configure-time option, now seems like a good time to remove it.
Also see <http://bugs.gnu.org/11080#16>.
* configure.ac (SYNC_INPUT, BROKEN_SA_RESTART): Remove.
* admin/CPP-DEFINES (BROKEN_SA_RESTART, SA_RESTART): Remove.
* etc/TODO (Make SYNC_INPUT the default): Remove, as the code now
behaves as if SYNC_INPUT is always true.
* src/alloc.c (_bytes_used, __malloc_extra_blocks, _malloc_internal)
(_free_internal) [!DOUG_LEA_MALLOC]: Remove decls.
(alloc_mutex) [!SYSTEM_MALLOC && !SYNC_INPUT && HAVE_PTHREAD]:
(malloc_hysteresis):
(check_depth) [XMALLOC_OVERRUN_CHECK]:
(MALLOC_BLOCK_INPUT, MALLOC_UNBLOCK_INPUT):
(__malloc_hook, __realloc_hook, __free_hook, BYTES_USED)
(dont_register_blocks, bytes_used_when_reconsidered)
(bytes_used_when_full, emacs_blocked_free, emacs_blocked_malloc)
(emacs_blocked_realloc, reset_malloc_hooks, uninterrupt_malloc):
[!SYSTEM_MALLOC && !SYNC_INPUT]:
Remove. All uses removed.
(MALLOC_BLOCK_INPUT, MALLOC_UNBLOCK_INPUT): Use a different
implementation, one that depends on whether the new macro
XMALLOC_BLOCK_INPUT_CHECK is defined, not on whether SYNC_INPUT
is defined.
* src/atimer.c (run_timers, handle_alarm_signal):
* src/keyboard.c (pending_signal, poll_for_input_1, poll_for_input)
(handle_async_input, process_pending_signals)
(handle_input_available_signal, init_keyboard):
* src/nsterm.m (ns_read_socket):
* src/process.c (wait_reading_process_output):
* src/regex.c (immediate_quit, IMMEDIATE_QUIT_CHECK):
* src/sysdep.c (emacs_sigaction_init) [SA_RESTART]:
(emacs_write):
* src/xterm.c (XTread_socket):
Assume SYNC_INPUT.
* src/conf_post.h (SA_RESTART) [IRIX6_5]: Do not #undef.
* src/eval.c (handling_signal): Remove.  All uses removed.
* src/lisp.h (ELSE_PENDING_SIGNALS): Remove.
All uses replaced with the SYNC_INPUT version.
(reset_malloc_hooks, uninterrupt_malloc, handling_signal):
Remove decls.
* src/sysdep.c, src/syssignal.h (main_thread) [FORWARD_SIGNAL_TO_MAIN_THREAD]:
Now static.

Fixes: debbugs:12450

* configure.ac (HAVE__SETJMP, HAVE_SIGSETJMP): New symbols.
(_setjmp, _longjmp): Remove.
* src/lisp.h: Include <setjmp.h> here, since we use its symbols here.
All instances of '#include <setjmp.h>' removed, if the
only reason for the instance was because "lisp.h" was included.
(sys_jmp_buf, sys_setjmp, sys_longjmp): New symbols.
Unless otherwise specified, replace all uses of jmp_buf, _setjmp,
and _longjmp with the new symbols.  Emacs already uses _setjmp if
available, so this change affects only POSIXish hosts that have
sigsetjmp but not _setjmp, such as some versions of Solaris and
Unixware.  (Also, POSIX-2008 marks _setjmp as obsolescent.)
* src/image.c (_setjmp, _longjmp) [HAVE_PNG && !HAVE__SETJMP]: New macros.
(png_load_body) [HAVE_PNG]:
(PNG_LONGJMP) [HAVE_PNG && PNG_LIBPNG_VER < 10500]:
(PNG_JMPBUF) [HAVE_PNG && PNG_LIBPNG_VER >= 10500]:
Use _setjmp and _longjmp rather than sys_setjmp and sys_longjmp,
since PNG requires jmp_buf.  This is the only exception to the
general rule that we now use sys_setjmp and sys_longjmp.
This exception is OK since this code does not change the signal
mask or longjmp out of a signal handler.

Fixes: debbugs:12446

The code that dealt with SIGIO was crufty and confusing, e.g., it
played tricks like "#undef SIGIO" but these tricks were not used
consistently.  Simplify mostly by not #undeffing standard symbols,
e.g., use "defined USABLE_SIGIO" (our symbol, which we can define
or not as we please) rather than "defined SIGIO" (standard symbol
that we probably shouldn't #undef).
* configure.ac (NO_TERMIO, BROKEN_FIONREAD, BROKEN_SIGAIO)
(BROKEN_SIGPOLL, BROKEN_SIGPTY): Remove.
(USABLE_FIONREAD, USABLE_SIGIO): New symbols.  All uses of
'defined SIGIO' replaced with 'defined USABLE_SIGIO', with no need
to #undef SIGIO now (which was error-prone).  Likewise, all uses
of 'defined FIONREAD' replaced with 'defined USABLE_FIONREAD'.
* src/admin/CPP_DEFINES (BROKEN_SIGAIO, BROKEN_SIGIO, BROKEN_SIGPOLL)
(BROKEN_SIGPTY, NO_TERMIO): Remove.
* src/conf_post.h [USG5_4]: Do not include <sys/wait.h> here.
Modules that need it can include it.
[USG5_4 && emacs]: Likewise, do not include the streams stuff here.
* src/dispextern.h (ignore_sigio): New decl.
* src/emacs.c (shut_down_emacs): Invoke unrequest_sigio
unconditionally, since it's now a no-op if !USABLE_SIGIO.
* src/emacs.c (shut_down_emacs):
* src/keyboard.c (kbd_buffer_store_event_hold):
Use ignore_sigio rather than invoking 'signal' directly.
* src/keyboard.c (USABLE_FIONREAD && USG5_4): Include <sys/filio.h>,
for FIONREAD.
(FIONREAD, SIGIO): Do not #undef.
(tty_read_avail_input): Use #error rather than a syntax error.
* src/process.c [USG5_4]: Include <sys/stream.h> and <sys/stropts.h>,
for I_PIPE, used by SETUP_SLAVE_PTY.
(DATAGRAM_SOCKETS): Simplify defn, based on USABLE_FIONREAD.
* src/sysdep.c (croak): Remove; no longer needed.  This bit of
temporary code, with Fred N. Fish's comment that it's temporary,
has been in Emacs since at least 1992!
(init_sigio, reset_sigio, request_sigio, unrequest_sigio):
Arrange for them to be no-ops in all cases when ! USABLE_SIGIO.
* src/syssignal.h (croak): Remove decl.
(SIGIO, SIGPOO, SIGAIO, SIGPTY): Do not #undef; that's too fragile.
* src/systty.h [!NO_TERMIO]: Do not include <termio.h>; no longer needed
now that we're termios-only.
(FIONREAD, ASYNC) [BROKEN_FIONREAD]: Do not #undef.
* src/term.c (dissociate_if_controlling_tty): Use #error rather than
a run-time error.

Fixes: debbugs:12408

This simplifies the code, and makes it a bit smaller and faster,
and (most important) makes it easier to clean up signal handling
since we can stop worring about floating-point exceptions in
library code.  That was a problem before C89, but the problem
went away many years ago on all practical Emacs targets.
* configure.ac (frexp, fmod): Remove checks for these functions,
as we now assume them.
(FLOAT_CHECK_DOMAIN, HAVE_INVERSE_HYPERBOLIC, NO_MATHERR)
(HAVE_EXCEPTION):
Remove; no longer needed.
* admin/CPP-DEFINES (HAVE_FMOD, HAVE_FREXP, FLOAT_CHECK_DOMAIN)
(HAVE_INVERSE_HYPERBOLIC, NO_MATHERR): Remove.
* src/data.c, src/image.c, src/lread.c, src/print.c:
Don't include <math.h>; no longer needed.
* src/data.c, src/floatfns.c (IEEE_FLOATING_POINT): Don't worry that it
might be autoconfigured, as that never happens.
* src/data.c (fmod):
* src/doprnt.c (DBL_MAX_10_EXP):
* src/print.c (DBL_DIG):
Remove.  C89 or later always defines these.
* src/floatfns.c (HAVE_MATHERR, FLOAT_CHECK_ERRNO, FLOAT_CHECK_DOMAIN)
(in_float, float_error_arg, float_error_arg2, float_error_fn_name)
(arith_error, domain_error, domain_error2):
Remove all this pre-C89 cruft.  Do not include <errno.h> as that's
no longer needed -- we simply return what C returns.  All uses removed.
(IN_FLOAT, IN_FLOAT2): Remove.  All uses replaced with
the wrapped code.
(FLOAT_TO_INT, FLOAT_TO_INT2, range_error, range_error2):
Remove.  All uses expanded, as these macros are no longer used
more than once and are now more trouble than they're worth.
(Ftan): Use tan, not sin / cos.
(Flogb): Assume C89 frexp.
(fmod_float): Assume C89 fmod.
(matherr) [HAVE_MATHERR]: Remove; no longer needed.
(init_floatfns): Remove.  All uses removed.

Problem introduced when merging patches.  Noted by Eli Zaretskii in
<http://bugs.gnu.org/12327#67>.

Emacs's signal handlers were written in the old 4.2BSD style with
sigblock and sigmask and so forth, and this led to some
inefficiencies and confusion.  Rewrite these to use
pthread_sigmask etc. without copying signal sets around.  Also,
get rid of the confusing macros 'SIGNAL_THREAD_CHECK' and
'signal', and instead use functions that do not attempt to take
over the system name space.  This patch causes Emacs's text
segment to shrink by 0.7% on my platform, Fedora 17 x86-64.
* configure.ac (PTY_OPEN, PTY_TTY_NAME_SPRINTF):
Adjust to syssignal.h changes.
(SIGNAL_H_AB): Remove; no longer needed.
* src/alloc.c, src/emacsgtkfixed.c, src/nsfns.m, src/widget.c, src/xmenu.c:
Do not include <signal.h> or "syssignal.h", as these
modules do not use signals.
* src/atimer.c, src/callproc.c, src/data.c, src/dispnew.c, src/emacs.c:
* src/floatfns.c, src/gtkutil.c, src/keyboard.c, src/process.c, src/sound.c:
* src/sysdep.c, src/term.c, src/xterm.c:
Do not include <signal.h>, as "syssignal.h" does that for us now.
* src/atimer.c (sigmask_atimers): New function.
(block_atimers, unblock_atimers): New functions,
replacing the old macros BLOCK_ATIMERS and UNBLOCK_ATIMERS.
All uses replaced.
* src/conf_post.h [SIGNAL_H_AHB]: Do not include <signal.h>;
no longer needed here.
* src/emacs.c (main): Inspect existing signal handler with sigaction,
so that there's	no need to block and unblock SIGHUP.
* src/sysdep.c (struct save_signal): New member 'action', replacing
old member 'handler'.
(save_signal_handlers, restore_signal_handlers):
Use sigaction instead of 'signal' to save and restore.
(get_set_sighandler, set_sighandler) [!WINDOWSNT]:
New function.  All users of 'signal' modified to use set_sighandler
if they're writeonly, and to use sys_signal if they're read+write.
(emacs_sigaction_init, forwarded_signal): New functions.
(sys_signal): Remove.  All uses replaced by calls to sigaction
and emacs_sigaction_init, or by direct calls to 'signal'.
(sys_sigmask) [!__GNUC__]: Remove; no longer needed.
(sys_sigblock, sys_sigunblock, sys_sigsetmask): Remove;
all uses replaced by pthread_sigmask etc. calls.
* src/syssignal.h: Include <signal.h>.
(emacs_sigaction_init, forwarded_signal): New decls.
(SIGMASKTYPE): Remove.  All uses replaced by its definiens, sigset_t.
(SIGEMPTYMASK): Remove; all uses replaced by its definiens, empty_mask.
(sigmask, sys_sigmask): Remove; no longer needed.
(sigpause): Remove.  All uses replaced by its definiens, sigsuspend.
(sigblock, sigunblock, sigfree):
(sigsetmask) [!defined sigsetmask]:
Remove.  All uses replaced by pthread_sigmask.
(signal): Remove.  Its remaining uses (with SIG_DFL and SIG_IGN)
no longer need to be replaced, and its typical old uses
are now done via emacs_sigaction_init and sigaction.
(sys_sigblock, sys_sigunblock, sys_sigsetmask): Remove decls.
(sys_sigdel): Remove; unused.
(NSIG): Remove a FIXME; the code's fine.  Remove an unnecessary ifdef.

Fixes: debbugs:12327

Be more systematic about preserving errno whenever a signal
handler returns, even if it's not in the main thread.  Do this by
renaming signal handlers to distinguish between signal delivery
and signal handling.  All uses changed.
* atimer.c (deliver_alarm_signal): Rename from alarm_signal_handler.
* data.c (deliver_arith_signal): Rename from arith_error.
* dispnew.c (deliver_window_change_signal): Rename from
window_change_signal.
* emacs.c (deliver_error_signal): Rename from fatal_error_signal.
(deliver_danger_signal) [SIGDANGER]: Rename from memory_warning_signal.
* keyboard.c (deliver_input_available_signal): Rename from
input_available_signal.
(deliver_user_signal): Rename from handle_user_signal.
(deliver_interrupt_signal): Rename from interrupt_signal.
* process.c (deliver_pipe_signal): Rename from send_process_trap.
(deliver_child_signal): Rename from sigchld_handler.
* atimer.c (handle_alarm_signal):
* data.c (handle_arith_signal):
* dispnew.c (handle_window_change_signal):
* emacs.c (handle_fatal_signal, handle_danger_signal):
* keyboard.c (handle_input_available_signal):
* keyboard.c (handle_user_signal, handle_interrupt_signal):
* process.c (handle_pipe_signal, handle_child_signal):
New functions, with the actual signal-handling code taken from the
original respective signal handlers, sans the sporadic attempts to
preserve errno, since that's now done by handle_on_main_thread.
* atimer.c (alarm_signal_handler): Remove unnecessary decl.
* emacs.c, floatfns.c, lisp.h: Remove unused FLOAT_CATCH_SIGKILL cruft.
* emacs.c (main_thread) [FORWARD_SIGNAL_TO_MAIN_THREAD]:
Move to sysdep.c.
(main) [FORWARD_SIGNAL_TO_MAIN_THREAD]:
Move initialization of main_thread to sysdep.c's init_signals.
* process.c (waitpid) [!WNOHANG]: #define to wait; that's good enough for
our usage, and simplifies the mainline code.
(record_child_status_change): New static function, as a helper
for handle_child_signal, and with most of the old child handler's
contents.
(CAN_HANDLE_MULTIPLE_CHILDREN): New constant.
(handle_child_signal): Use the above.
* sysdep.c (main_thread) [FORWARD_SIGNAL_TO_MAIN_THREAD]:
Moved here from emacs.c.
(init_signals) [FORWARD_SIGNAL_TO_MAIN_THREAD]: Initialize it;
code moved here from emacs.c's main function.
* sysdep.c, syssignal.h (handle_on_main_thread): New function,
replacing the old SIGNAL_THREAD_CHECK.  All uses changed.  This
lets callers save and restore errno properly.

* doc/emacs/trouble.texi (Crashing): New section, documenting this.
* etc/NEWS: Document the change.
* src/alloc.c [ENABLE_CHECKING]: Do not include <execinfo.h>.
(die) [ENABLE_CHECKING]: Call fatal_error_backtrace instead
of doing the work ourselves.
* src/emacs.c (fatal_error_signal): Let fatal_error_backtrace
do most of the work.
(fatal_error_backtrace): New function, taken from the guts
of the old fatal_error_signal, but with a new option to output
a backtrace.
(shut_down_emacs) [!DOS_NT]: Use strsignal to give more-useful
info about the signal than just its number.
* src/lisp.h (fatal_error_backtrace, emacs_backtrace): New decls.
* src/sysdep.c: Include <execinfo.h>
(emacs_backtrace): New function, taken partly from the previous
code of the 'die' function.
(emacs_abort): Call fatal_error_backtrace rather than abort.

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.

* emacs.c (initialized, inhibit_window_system, running_asynch_code):
(malloc_using_checking) [DOUG_LEA_MALLOC]:
(display_arg) [HAVE_X_WINDOWS || HAVE_NS]:
(noninteractive, no_site_lisp, fatal_error_in_progress, argmatch)
(main, decode_env_path, Fdaemon_initialized):
* eval.c (call_debugger, Finteractive_p, interactive_p):
(unwind_to_catch, Fsignal, wants_debugger, skip_debugger)
(maybe_call_debugger, Fbacktrace):
* process.c (read_process_output, exec_sentinel):
Use bool for booleans.
* emacs.c (shut_down_emacs): Omit unused boolean argument NO_X.
All callers changed.
* eval.c (interactive_p): Omit always-true boolean argument
EXCLUDE_SUBRS_P.  All callers changed.
* dispextern.h, lisp.h: Reflect above API changes.
* firstfile.c (dummy): Use the address of 'main', whose signature
won't change, instead of the address of 'initialize', whose
signature just changed from int to bool.
* lisp.h (fatal_error_in_progress): New decl of boolean, moved here ...
* msdos.c (fatal_error_in_progress): ... from here.
* xdisp.c (redisplaying_p): Now a boolean.  Set it to 1 instead
of incrementing it.
(redisplay_internal, unwind_redisplay): Simply clear
REDISPLAYING_P when unwinding, instead of saving its previous,
always-false value and then restoring it.

This change streamlines the window system selection code in
configure.in and moves many common function declarations from
window-specific headers to frame.h.  It introduces a new TERM_HEADER
macro in config.h: we set this macro to the right header to use for
the window system for which we're compiling Emacs and have source
files include it indirectly.  This way, we don't have to teach every
file about every window system.

* doc/lispref/numbers.texi (Random Numbers): Document new behavior of
the calls (random) and (random STRING).
* etc/NEWS: Document new behavior of (random), (random "string").
* lisp/play/5x5.el, lisp/play/animate.el, lisp/play/cookie1.el:
* lisp/play/dissociate.el, lisp/play/doctor.el, lisp/play/dunnet.el:
* lisp/play/gomoku.el, lisp/play/landmark.el, lisp/play/mpuz.el:
* lisp/play/tetris.el, lisp/play/zone.el:
* lisp/calc/calc-comb.el (math-init-random-base):
* lisp/play/blackbox.el (bb-init-board):
* lisp/play/life.el (life):
* lisp/server.el (server-use-tcp):
* lisp/type-break.el (type-break):
Remove unnecessary call to (random t).
* lisp/net/sasl.el (sasl-unique-id-function):
Change (random t) to (random), now that the latter is more random.
* lisp/play/life.el (life-initialized): Remove no-longer-needed var.
* lisp/gnus/gnus-sync.el (gnus-sync-lesync-setup):
* lisp/gnus/message.el (message-canlock-generate, message-unique-id):
Change (random t) to (random), now that the latter is more random.
* lisp/org/org-id.el (org-id-uuid):
Change (random t) to (random), now that the latter is more random.
* src/emacs.c (main): Call init_random.
* src/fns.c (Frandom): Set the seed from a string argument, if given.
Remove long-obsolete Gentzel cruft.
* src/lisp.h, src/sysdep.c (seed_random): Now takes address and size, not long.
(init_random): New function.

All uses removed.  This leftover from old code was always 0.

as gnulib does this if the system doesn't.
* lib-src/emacsclient.c (environ): Remove decl.
* src/callproc.c, src/editfns.c, src/process.c (environ) [!USE_CRT_DLL]:
* src/emacs.c (environ) [DOUG_LEA_MALLOC]:
* src/vm-limit.c (environ) [ORDINARY_LINK]: Remove decl.
* src/vm-limit.c: Include <unistd.h>, for 'environ'.

* lisp/files.el (kill-buffer-hook): Provide a defvar.

* src/term.c (Vsuspend_tty_functions, Vresume_tty_functions):
* src/frame.c (Vdelete_frame_functions):
* src/emacs.c (Vkill_emacs_hook): Doc fix.

 src/w32.c (init_environment): Change the default values of many
 environment variables in dflt_envvars[] to NULL, to avoid pushing
 them into environment when they were not already defined.  Remove
 the code that deletes site-lisp subdirectories from the default
 value of EMACSLOADPATH, as it is no longer needed.
 (check_windows_init_file): Now external, not static.  Use
 Vload_path as is, without adding anything, as this function is now
 called when Vload_path is already set up.
 src/w32.h (check_windows_init_file): Add prototype.
 src/emacs.c (init_cmdargs) [WINDOWSNT]: When running from the build
 directory, ignore the /*/i386/ tail in Vinvocation_directory, for
 compatibility with Posix platforms.
 (main): Move the call to check_windows_init_file to here from
 w32.c.
 (decode_env_path) [WINDOWSNT]: Expand the %emacs_dir%/ prefix, if
 any, in the DEFALT argument into the root of the Emacs build or
 installation tree, as appropriate.
 src/callproc.c (init_callproc_1): Call decode_env_path instead of
 doing its equivalent by hand.
 (init_callproc): Replace DOS_NT condition with MSDOS, thus letting
 the code that sets Vexec_path run on MS-Windows.
 src/lread.c (init_lread): Add comments to #ifdef's.

 nt/paths.h (PATH_LOADSEARCH, PATH_SITELOADSEARCH, PATH_EXEC)
 (PATH_DATA, PATH_DOC): Replace dummy directory names with
 directories relative to %emacs_dir%.
 (PATH_EXEC): Add lib-src/oo-spd/i386 and lib-src/oo/i386, to cater
 to the use case of running un-installed Emacs.

* src/editfns.c (USER_FULL_NAME):
* src/emacs.c (SEPCHAR):
* src/process.h (NULL_DEVICE): Let configure set them.

Fixes: debbugs:12036