Redo src/*.h so that each include file is idempotent (that is, can
be included multiple times with the latter inclusions having no
effect) and standalone (that is, can be included by itself,
with no include file other than config.h needed as a prerequisite).
This is standard practice in GNU programs nowadays.
* lwlib/lwlib-widget.h, src/buffer.h, src/category.h, src/character.h:
* src/charset.h, src/coding.h, src/commands.h, src/disptab.h:
* src/fontset.h, src/gnutls.h, src/indent.h, src/keymap.h, src/macros.h:
* src/regex.h [emacs]:
* src/syntax.h, src/systty.h, src/termhooks.h:
Include lisp.h, for Lisp_Object.
* src/buffer.h, src/category.h, src/cm.h, src/commands.h, src/disptab.h:
* src/indent.h, src/intervals.h, src/keyboard.h, src/macros.h:
* src/process.h, src/puresize.h, src/region-cache.h, src/syntax.h:
* src/syssignal.h, src/sysstdio.h, src/systty.h, src/termchar.h:
* src/termopts.h, src/tparam.h, src/unexec.h:
Protect against multiple inclusion.
* src/buffer.h: Include character.h, for STRING_CHAR.
* src/emacsgtkfixed.h (struct frame):
* src/fontset.h (struct face):
* src/region-cache.h (struct buffer):
* src/termhooks.h (struct glyph):
* src/xsettings.h (struct x_display_info):
Add possibly-forward decl.
* src/syntax.h: Include buffer.h, for BVAR.
* src/sysselect.h: Include lisp.h, for eassume.
* src/termchar.h: Include <stdio.h>, for FILE.
* src/widget.h: Include <X11/IntrinsicP.h>, for Widget.
* src/xsettings.h: Include <X11/Xlib.h>, for XEvent.

Run admin/update-copyright.

 src/sysselect.h (fd_CLR, fd_ISSET, fd_SET, FD_CLR, FD_ISSET)
 (FD_SET): Don't define on WINDOWSNT.

* process.c (add_read_fd, delete_read_fd, add_write_fd)
(delete_write_fd, wait_reading_process_output):
Remove now-redundant easserts.
* sysselect.h (SYSSELECT_H): New macro, to avoid double-inclusion woes.
Use INLINE_HEADER_BEGIN, INLINE_HEADER_END.
(fd_CLR, fd_ISSET, fd_SET): New inline functions.
(FD_CLR, FD_ISSET, FD_SET): Redefine in terms of these functions.

Like EMACS_TIME, this portability layer is no longer needed, since
Emacs has been using fd_set as a portability layer for some time.
* sysselect.h (FD_SETSIZE): Rename from MAXDESC.  All uses changed.
(SELECT_TYPE): Remove.  All uses changed to fd_set.
(fd_set) [!FD_SET]: New typedef.

The old name is also the name of a Mach system call.

* src/process.c (init_process_emacs): Rename from init_process.

* src/lisp.h, src/emacs.c: Update for this name change.

* src/nsgui.h, src/sysselect.h, src/s/darwin.h:
Remove workaround that is no longer needed.

  
  msdos/mainmake.v2 (bootstrap-clean): Do a maintainer-clean in lib, not
  bootstrap-clean (which doesn't exist).
  msdos/inttypes.h (PRIuMAX) [__DJGPP__ < 2.04]: Define to "llu".
  msdos/sedleim.inp (MKDIR_P): Edit to DOS "md" command.
  msdos/sed1v2.inp: (LIB_CLOCK_GETTIME): Edit to empty.
  Remove lines that invoke PAXCTL.
  (clean): Fix recipe not to run Unixy shell commands.
  msdos/sed2v2.inp (GETTIMEOFDAY_TIMEZONE): Edit to 'struct timezone'.
  (HAVE_STRNCASECMP): Edit to 1.
  msdos/sed3v2.inp (LIB_CLOCK_GETTIME): Edit to empty.
  (C_SWITCH_SYSTEM): Add "-I../msdos".
  msdos/sedlibmk.inp (GNULIB_GETTIMEOFDAY, GNULIB_PSELECT)
  (GNULIB_SELECT, HAVE_STRUCT_TIMEVAL, HAVE_SYS_SELECT_H)
  (HAVE_SYS_TIME_H, NEXT_AS_FIRST_DIRECTIVE_SYS_SELECT_H)
  (NEXT_AS_FIRST_DIRECTIVE_SYS_TIME_H, NEXT_SYS_SELECT_H)
  (NEXT_SYS_TIME_H, REPLACE_GETTIMEOFDAY, REPLACE_PSELECT)
  (REPLACE_STRUCT_TIMEVAL): Edit to appropriate values.
  (BUILT_SOURCES): Edit out sys/select.h and sys/time.h.
  (mostlyclean-local, distclean-generic): Fix recipe not to run
  Unixy shell commands.

  src/sysselect.h [DOS_NT]: Don't include sys/select.h.
  src/sysselect.h (pselect) [!HAVE_PSELECT]: Redirect to sys_select.
  src/sysdep.c: Don't include dos.h and dosfns.h.
  src/process.c (sys_select):
  src/msdos.c (sys_select): Accept one more argument and ignore it.
  src/msdos.c (event_timestamp, sys_select): Use gnulib's gettime;
  adapt data types and code to that.
  src/dosfns.c:
  src/msdos.c (gettime, settime): Define away the prototypes in dos.h,
  which clashes with the gnulib function of the same name.
  src/ w32proc.c (sys_select): Accept and ignore one more argument.
  src/w32.c (emacs_gnutls_pull): Call select with one more argument.

  lisp/emacs-lisp/timer.el (timer-until): Subtract results of
  float-time, instead of taking float-time of the result of
  time-subtract, since float-time signals an error for negative time
  arguments.

 msdos/mainmake.v2 (bootstrap-clean): Do a maintainer-clean in lib, not
 bootstrap-clean (which doesn't exist).
 msdos/inttypes.h (PRIuMAX) [__DJGPP__ < 2.04]: Define to "llu".
 msdos/sedleim.inp (MKDIR_P): Edit to DOS "md" command.
 msdos/sed1v2.inp: (LIB_CLOCK_GETTIME): Edit to empty.
 Remove lines that invoke PAXCTL.
 (clean): Fix recipe not to run Unixy shell commands.
 msdos/sed2v2.inp (GETTIMEOFDAY_TIMEZONE): Edit to 'struct timezone'.
 (HAVE_STRNCASECMP): Edit to 1.
 msdos/sed3v2.inp (LIB_CLOCK_GETTIME): Edit to empty.
 (C_SWITCH_SYSTEM): Add "-I../msdos".
 msdos/sedlibmk.inp (GNULIB_GETTIMEOFDAY, GNULIB_PSELECT)
 (GNULIB_SELECT, HAVE_STRUCT_TIMEVAL, HAVE_SYS_SELECT_H)
 (HAVE_SYS_TIME_H, NEXT_AS_FIRST_DIRECTIVE_SYS_SELECT_H)
 (NEXT_AS_FIRST_DIRECTIVE_SYS_TIME_H, NEXT_SYS_SELECT_H)
 (NEXT_SYS_TIME_H, REPLACE_GETTIMEOFDAY, REPLACE_PSELECT)
 (REPLACE_STRUCT_TIMEVAL): Edit to appropriate values.
 (BUILT_SOURCES): Edit out sys/select.h and sys/time.h.
 (mostlyclean-local, distclean-generic): Fix recipe not to run
 Unixy shell commands.

 src/sysselect.h [DOS_NT]: Don't include sys/select.h.
 src/s/ms-w32.h (select, pselect): Don't define here, they are
 defined in sysselect.h
 src/sysselect.h (pselect) [!HAVE_PSELECT]: Redirect to sys_select.
 src/sysdep.c: Don't include dos.h and dosfns.h.
 src/process.c (sys_select):
 src/msdos.c (sys_select): Accept one more argument and ignore it.
 src/msdos.c (event_timestamp, sys_select): Use gnulib's gettime;
 adapt data types and code to that.
 src/dosfns.c:
 src/msdos.c (gettime, settime): Define away the prototypes in dos.h,
 which clashes with the gnulib function of the same name.

 lisp/emacs-lisp/timer.el (timer-until): Subtract results of
 float-time, instead of taking float-time of the result of
 time-subtract, since float-time signals an error for negative time
 arguments.