Fix the MSDOS build

* config.bat:
* msdos/sedlisp.inp:
* msdos/sedlibmk.inp:
* msdos/sedleim.inp:
* msdos/sedadmin.inp:
* msdos/sed6.inp:
* msdos/sed3v2.inp:
* msdos/sed2v2.inp:
* msdos/sed1v2.inp: Adapt to Emacs 25.

* src/process.c (remove_slash_colon): Move out of "#ifdef
subprocesses" block, as it its called unconditionally.  Move
ADD_SUBFEATURE calls into "#ifdef subprocesses" block, as they
reference variables only defined in that block.
* src/msdos.h: Provide prototypes for IT_set_frame_parameters,
faccessat, msdos_fatal_signal, syms_of_msdos, pthread_sigmask,
dos_keysns, dos_keyread, run_msdos_command, and
syms_of_win16select, to avoid compiler warnings.
* src/msdos.c (SYS_ENVIRON): Define to either '_environ' or
'environ', depending on the DJGPP version.
Remove declarations of externally-visible Lisp objects, like
Qbackground_color and Qreverse.
(run_msdos_command): First argument is not signed, not unsigned.
Use SYS_ENVIRON.
(sys_select): Use 'timespec_cmp' instead of 'timespec_sign', as
the latter doesn't work when 'time_t' is an unsigned data type.
This caused idle timers to behave incorrectly: they only fired
after a keyboard input event.
* src/frame.c (adjust_frame_size) [MSDOS]: Account for
FRAME_TOP_MARGIN that isn't counted in the frame's number of
lines, but dos_set_window_size needs it to be added.
* src/lread.c (INFINITY, NAN) [DJGPP < 2.05]: Provide definitions.
* src/fns.c (sort_vector_copy) [__GNUC__ < 4]: Provide a prototype
that works around compilation errors with older GCC versions.
* src/w16select.c: Don't declare QCLIPBOARD and QPRIMARY as Lisp
Objects.
* src/filelock.c [MSDOS]: Ifdef away most of the code.  Provide
no-op implementations for 'lock_file' and 'unlock_file'.
(Ffile_locked_p) [MSDOS]: Always return nil.  This avoids multiple
ifdefs in all users of filelock.c functionality.
* src/conf_post.h (EOVERFLOW, SIZE_MAX) [DJGPP < 2.04]: Define.
* src/emacs.c [MSDOS]: Include dosfns.h, to avoid compiler
warnings.
* src/dosfns.h: Provide prototypes for dos_cleanup,
syms_of_dosfns, and init_dosfns.
* src/deps.mk (atimer.o): Depend on msdos.h.
(emacs.o): Depend on dosfns.h.
* src/atimer.c [MSDOS]: Include msdos.h, to avoid compiler
warnings.

* lisp/window.el (window--adjust-process-windows): Skip the body
if 'process-list' is not available.  This avoids failure to start
up on MS-DOS.
* lisp/vc/diff.el (diff-no-select): Test 'make-process', not
'start-process', as the latter is now available on all platforms.
* lisp/textmodes/ispell.el (ispell-async-processp): Replace
'start-process' with 'make-process' in a comment.
* lisp/term/internal.el (IT-unicode-translations): Modify and add
a few translations to display Info files with Unicode markup.  Fix
an ancient off-by-one mismatch error with Unicode codepoints.
* lisp/progmodes/compile.el (compilation-start): Test
'make-process', not 'start-process', as the latter is now
available on all platforms.
* lisp/man.el (Man-build-man-command, Man-getpage-in-background):
Test 'make-process', not 'start-process', as the latter is now
available on all platforms.
* lisp/international/mule-cmds.el (set-coding-system-map): Test
'make-process', not 'start-process', as the latter is now
available on all platforms.
* lisp/eshell/esh-cmd.el (eshell-do-pipelines-synchronously): Doc
fix.
(eshell-execute-pipeline): Test 'make-process', not
'start-process', as the latter is now available on all platforms.

13 files changed, 102 insertions, 47 deletions

diff --git a/src/atimer.c b/src/atimer.c
index 70d9bf52bc2..64c9e8ab6cb 100644
--- a/src/atimer.c
+++ b/src/atimer.c
@@ -30,6 +30,10 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 # include <sys/timerfd.h>
 #endif
 
+#ifdef MSDOS
+#include "msdos.h"
+#endif
+
 /* Free-list of atimer structures.  */
 
 static struct atimer *free_atimers;
diff --git a/src/conf_post.h b/src/conf_post.h
index d0f04b63700..209f60792cf 100644
--- a/src/conf_post.h
+++ b/src/conf_post.h
@@ -145,6 +145,9 @@ You lose; /* Emacs for DOS must be compiled with DJGPP */
 # define HAVE_LSTAT 1
 #else
 # define lstat stat
+/* DJGPP 2.03 and older don't have the next two.  */
+# define EOVERFLOW ERANGE
+# define SIZE_MAX  4294967295U
 #endif
 
 /* We must intercept 'opendir' calls to stash away the directory name,
diff --git a/src/deps.mk b/src/deps.mk
index 0295e705a9c..72f68cabfc3 100644
--- a/src/deps.mk
+++ b/src/deps.mk
@@ -35,7 +35,7 @@
 ### Code:
 
 atimer.o: atimer.c atimer.h syssignal.h systime.h lisp.h blockinput.h \
- globals.h ../lib/unistd.h $(config_h)
+ globals.h ../lib/unistd.h msdos.h $(config_h)
 bidi.o: bidi.c buffer.h character.h dispextern.h msdos.h lisp.h \
    globals.h $(config_h)
 buffer.o: buffer.c buffer.h region-cache.h commands.h window.h \
@@ -92,7 +92,7 @@ editfns.o: editfns.c window.h buffer.h systime.h $(INTERVALS_H) character.h \
 emacs.o: emacs.c commands.h systty.h syssignal.h blockinput.h process.h \
    termhooks.h buffer.h atimer.h systime.h $(INTERVALS_H) lisp.h $(config_h) \
    globals.h ../lib/unistd.h window.h dispextern.h keyboard.h keymap.h \
-   frame.h coding.h gnutls.h msdos.h unexec.h
+   frame.h coding.h gnutls.h msdos.h dosfns.h unexec.h
 fileio.o: fileio.c window.h buffer.h systime.h $(INTERVALS_H) character.h \
    coding.h msdos.h blockinput.h atimer.h lisp.h $(config_h) frame.h \
    commands.h globals.h ../lib/unistd.h
diff --git a/src/dosfns.h b/src/dosfns.h
index 9fbf7eda192..849fb91a7af 100644
--- a/src/dosfns.h
+++ b/src/dosfns.h
@@ -24,6 +24,10 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 extern unsigned char dos_country_info[DOS_COUNTRY_INFO];
 extern int dos_memory_info (unsigned long *, unsigned long *,
                             unsigned long *, unsigned long *);
+void dos_cleanup (void);
+void syms_of_dosfns (void);
+void init_dosfns (void);
+
 #ifndef HAVE_X_WINDOWS
 extern int         msdos_stdcolor_idx  (const char *);
 extern Lisp_Object msdos_stdcolor_name (int);
diff --git a/src/emacs.c b/src/emacs.c
index d1d649dfcfd..5c187e76ba1 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -54,6 +54,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #ifdef MSDOS
 #include <binary-io.h>
+#include "dosfns.h"
 #endif
 
 #ifdef HAVE_WINDOW_SYSTEM
diff --git a/src/filelock.c b/src/filelock.c
index bc3a6209a8d..8aaa656438d 100644
--- a/src/filelock.c
+++ b/src/filelock.c
@@ -53,6 +53,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "w32.h"        /* for dostounix_filename */
 #endif
 
+#ifndef MSDOS
+
 #ifdef HAVE_UTMP_H
 #include <utmp.h>
 #endif
@@ -742,6 +744,19 @@ unlock_file (Lisp_Object fn)
   SAFE_FREE ();
 }
 
+#else  /* MSDOS */
+void
+lock_file (Lisp_Object fn)
+{
+}
+
+void
+unlock_file (Lisp_Object fn)
+{
+}
+
+#endif  /* MSDOS */
+
 void
 unlock_all_files (void)
 {
@@ -805,6 +820,9 @@ The value is nil if the FILENAME is not locked,
 t if it is locked by you, else a string saying which user has locked it.  */)
   (Lisp_Object filename)
 {
+#ifdef MSDOS
+  return Qnil;
+#else
   Lisp_Object ret;
   char *lfname;
   int owner;
@@ -825,6 +843,7 @@ t if it is locked by you, else a string saying which user has locked it.  */)
 
   SAFE_FREE ();
   return ret;
+#endif
 }
 
 void
diff --git a/src/fns.c b/src/fns.c
index 47ed2d82207..a65863ce0e8 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -32,8 +32,13 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "intervals.h"
 #include "window.h"
 
+#if __GNUC__ >= 4
 static void sort_vector_copy (Lisp_Object, ptrdiff_t,
                               Lisp_Object [restrict], Lisp_Object [restrict]);
+#else
+static void sort_vector_copy (Lisp_Object, ptrdiff_t,
+                              Lisp_Object [], Lisp_Object []);
+#endif
 static bool internal_equal (Lisp_Object, Lisp_Object, int, bool, Lisp_Object);
 
 DEFUN ("identity", Fidentity, Sidentity, 1, 1, 0,
diff --git a/src/frame.c b/src/frame.c
index 53ff05965c1..00f25f7e911 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -509,10 +509,13 @@ adjust_frame_size (struct frame *f, int new_width, int new_height, int inhibit,
   block_input ();
 
 #ifdef MSDOS
-  /* We only can set screen dimensions to certain values supported
-     by our video hardware.  Try to find the smallest size greater
-     or equal to the requested dimensions.  */
-  dos_set_window_size (&new_lines, &new_cols);
+  /* We only can set screen dimensions to certain values supported by
+     our video hardware.  Try to find the smallest size greater or
+     equal to the requested dimensions, while accounting for the fact
+     that the menu-bar lines are not counted in the frame height.  */
+  int dos_new_lines = new_lines + FRAME_TOP_MARGIN (f);
+  dos_set_window_size (&dos_new_lines, &new_cols);
+  new_lines = dos_new_lines - FRAME_TOP_MARGIN (f);
 #endif
 
   if (new_windows_width != old_windows_width)
diff --git a/src/lread.c b/src/lread.c
index 91469230b7e..d374406e7b9 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -46,6 +46,10 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #ifdef MSDOS
 #include "msdos.h"
+#if __DJGPP__ == 2 && __DJGPP_MINOR__ < 5
+# define INFINITY  __builtin_inf()
+# define NAN       __builtin_nan("")
+#endif
 #endif
 
 #ifdef HAVE_NS
diff --git a/src/msdos.c b/src/msdos.c
index 84e8c39ec0c..62411ea2f6d 100644
--- a/src/msdos.c
+++ b/src/msdos.c
@@ -59,6 +59,12 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <libc/dosio.h>  /* for _USE_LFN */
 #include <conio.h>       /* for cputs */
 
+#if (__DJGPP__ + (__DJGPP_MINOR__ > 3)) >= 3
+#define SYS_ENVIRON _environ
+#else
+#define SYS_ENVIRON environ
+#endif
+
 #include "msdos.h"
 #include "systime.h"
 #include "frame.h"
@@ -422,8 +428,6 @@ static unsigned long screen_old_address = 0;
 /* Segment and offset of the virtual screen.  If 0, DOS/V is NOT loaded.  */
 static unsigned short screen_virtual_segment = 0;
 static unsigned short screen_virtual_offset = 0;
-extern Lisp_Object Qcursor_type;
-extern Lisp_Object Qbar, Qhbar;
 
 /* The screen colors of the current frame, which serve as the default
    colors for newly-created frames.  */
@@ -1384,11 +1388,6 @@ IT_delete_glyphs (struct frame *f, int n)
 
 /* This was copied from xfaces.c  */
 
-extern Lisp_Object Qbackground_color;
-extern Lisp_Object Qforeground_color;
-Lisp_Object Qreverse;
-extern Lisp_Object Qtitle;
-
 /* IT_set_terminal_modes is called when emacs is started,
    resumed, and whenever the screen is redrawn!  */
 
@@ -3710,7 +3709,7 @@ dos_ttcooked (void)
    file TEMPOUT and stderr to TEMPERR.  */
 
 int
-run_msdos_command (unsigned char **argv, const char *working_dir,
+run_msdos_command (char **argv, const char *working_dir,
                    int tempin, int tempout, int temperr, char **envv)
 {
   char *saveargv1, *saveargv2, *lowcase_argv0, *pa, *pl;
@@ -3796,8 +3795,8 @@ run_msdos_command (unsigned char **argv, const char *working_dir,
         ;
       if (*cmnd)
         {
-          extern char **environ;
-          char **save_env = environ;
+          extern char **SYS_ENVIRON;
+          char **save_env = SYS_ENVIRON;
           int save_system_flags = __system_flags;
 
           /* Request the most powerful version of `system'.  We need
@@ -3809,16 +3808,16 @@ run_msdos_command (unsigned char **argv, const char *working_dir,
                              | __system_handle_null_commands
                              | __system_emulate_chdir);
 
-          environ = envv;
+          SYS_ENVIRON = envv;
           result = system (cmnd);
           __system_flags = save_system_flags;
-          environ = save_env;
+          SYS_ENVIRON = save_env;
         }
       else
         result = 0;     /* emulate Unixy shell behavior with empty cmd line */
     }
   else
-    result = spawnve (P_WAIT, argv[0], (char **)argv, envv);
+    result = spawnve (P_WAIT, argv[0], argv, envv);
 
   dup2 (inbak, 0);
   dup2 (outbak, 1);
@@ -4085,11 +4084,14 @@ sys_select (int nfds, fd_set *rfds, fd_set *wfds, fd_set *efds,
           gettime (&t);
           clnow = make_timespec (t.tv_sec, t.tv_nsec);
           cldiff = timespec_sub (clnow, cllast);
+          /* Stop when timeout value is about to cross zero.  */
+          if (timespec_cmp (*timeout, cldiff) <= 0)
+            {
+              timeout->tv_sec = 0;
+              timeout->tv_nsec = 0;
+              return 0;
+            }
           *timeout = timespec_sub (*timeout, cldiff);
-
-          /* Stop when timeout value crosses zero.  */
-          if (timespec_sign (*timeout) <= 0)
-            return 0;
           cllast = clnow;
           dos_yield_time_slice ();
         }
diff --git a/src/msdos.h b/src/msdos.h
index 863ca486e8d..0c3ba2bfa16 100644
--- a/src/msdos.h
+++ b/src/msdos.h
@@ -41,8 +41,12 @@ void mouse_on (void);
 void mouse_off (void);
 void mouse_moveto (int, int);
 
+void IT_set_frame_parameters (struct frame *, Lisp_Object);
+
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <pc.h>
+#include <signal.h>
 
 #if __DJGPP__ == 2 && __DJGPP_MINOR__ < 4
 int readlink (const char *, char *, size_t);
@@ -50,6 +54,16 @@ int readlink (const char *, char *, size_t);
 ssize_t readlinkat (int, const char *, char *, size_t);
 int fstatat (int, char const *, struct stat *, int);
 int unsetenv (const char *);
+int faccessat (int, const char *, int, int);
+void msdos_fatal_signal (int);
+void syms_of_msdos (void);
+int pthread_sigmask (int, const sigset_t *, sigset_t *);
+int dos_keysns (void);
+int dos_keyread (void);
+int run_msdos_command (char **, const char *, int, int, int, char **);
+
+void syms_of_win16select (void);
+
 
 /* Constants.  */
 #define EINPROGRESS 112
diff --git a/src/process.c b/src/process.c
index dd508836f79..2c758a4c9a7 100644
--- a/src/process.c
+++ b/src/process.c
@@ -4085,19 +4085,6 @@ Data that is unavailable is returned as nil.  */)
 #endif
 }
 
-/* If program file NAME starts with /: for quoting a magic
-   name, remove that, preserving the multibyteness of NAME.  */
-
-Lisp_Object
-remove_slash_colon (Lisp_Object name)
-{
-  return
-    ((SBYTES (name) > 2 && SREF (name, 0) == '/' && SREF (name, 1) == ':')
-     ? make_specified_string (SSDATA (name) + 2, SCHARS (name) - 2,
-                              SBYTES (name) - 2, STRING_MULTIBYTE (name))
-     : name);
-}
-
 /* Turn off input and output for process PROC.  */
 
 static void
@@ -7118,6 +7105,19 @@ add_timer_wait_descriptor (int fd)
 
 #endif /* HAVE_TIMERFD */
 
+/* If program file NAME starts with /: for quoting a magic
+   name, remove that, preserving the multibyteness of NAME.  */
+
+Lisp_Object
+remove_slash_colon (Lisp_Object name)
+{
+  return
+    ((SBYTES (name) > 2 && SREF (name, 0) == '/' && SREF (name, 1) == ':')
+     ? make_specified_string (SSDATA (name) + 2, SCHARS (name) - 2,
+                              SBYTES (name) - 2, STRING_MULTIBYTE (name))
+     : name);
+}
+
 /* Add DESC to the set of keyboard input descriptors.  */
 
 void
@@ -7643,13 +7643,6 @@ The variable takes effect when `start-process' is called.  */);
   defsubr (&Sset_process_filter_multibyte);
   defsubr (&Sprocess_filter_multibyte_p);
 
-#endif  /* subprocesses */
-
-  defsubr (&Sget_buffer_process);
-  defsubr (&Sprocess_inherit_coding_system_flag);
-  defsubr (&Slist_system_processes);
-  defsubr (&Sprocess_attributes);
-
  {
    Lisp_Object subfeatures = Qnil;
    const struct socket_options *sopt;
@@ -7684,4 +7677,10 @@ The variable takes effect when `start-process' is called.  */);
    Fprovide (intern_c_string ("make-network-process"), subfeatures);
  }
 
+#endif  /* subprocesses */
+
+  defsubr (&Sget_buffer_process);
+  defsubr (&Sprocess_inherit_coding_system_flag);
+  defsubr (&Slist_system_processes);
+  defsubr (&Sprocess_attributes);
 }
diff --git a/src/w16select.c b/src/w16select.c
index 434a5987893..208cfccf11a 100644
--- a/src/w16select.c
+++ b/src/w16select.c
@@ -65,8 +65,6 @@ unsigned get_clipboard_data (unsigned, void *, unsigned, int);
 unsigned close_clipboard (void);
 unsigned clipboard_compact (unsigned);
 
-Lisp_Object QCLIPBOARD, QPRIMARY;
-
 /* The segment address and the size of the buffer in low
    memory used to move data between us and WinOldAp module.  */
 static struct {
@@ -719,8 +717,7 @@ variable is set, it is used for the next communication only.
 After the communication, this variable is set to nil.  */);
   Vnext_selection_coding_system = Qnil;
 
-  QPRIMARY   = intern ("PRIMARY");      staticpro (&QPRIMARY);
-  QCLIPBOARD = intern ("CLIPBOARD");    staticpro (&QCLIPBOARD);
+  DEFSYM (QCLIPBOARD, "CLIPBOARD");
 }
 
 #endif /* MSDOS */