More signal-handler cleanup.

* configure.ac (FLOAT_CHECK_DOMAIN): Comment fix (Bug#12327).
* src/floatfns.c: Comment fix.
* src/lisp.h (force_auto_save_soon): Declare regardless of SIGDANGER.
SIGDANGER might not be in scope so "#ifdef SIGDANGER" is not right,
and anyway the declaration is harmless even if SIGDANGER is not defined.
* src/syssignal.h (SIGIO): Also #undef if (! defined FIONREAD ||
defined BROKEN_FIONREAD).  systty.h formerly did this, but other
source files not surprisingly expected syssignal.h to define, or
not define, SIGIO, and it's cleaner to do it that way, for consistency.
Include <sys/ioctl.h>, for FIONREAD.
* src/systty.h (SIGIO): Do not #undef here; it's now syssignal.h's job.
This eliminates a problem whereby other files mysteriously had
to include "syssignal.h" before including "systty.h" if they
wanted to use "#ifdef SIGIO".

5 files changed, 22 insertions, 9 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 068584969f7..8cab03fca50 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,20 @@
+2012-09-07  Paul Eggert  <eggert@cs.ucla.edu>
+
+        More signal-handler cleanup (Bug#12327).
+        * floatfns.c: Comment fix.
+        * lisp.h (force_auto_save_soon): Declare regardless of SIGDANGER.
+        SIGDANGER might not be in scope so "#ifdef SIGDANGER" is not right,
+        and anyway the declaration is harmless even if SIGDANGER is not defined.
+        * syssignal.h (SIGIO): Also #undef if (! defined FIONREAD ||
+        defined BROKEN_FIONREAD).  systty.h formerly did this, but other
+        source files not surprisingly expected syssignal.h to define, or
+        not define, SIGIO, and it's cleaner to do it that way, for consistency.
+        Include <sys/ioctl.h>, for FIONREAD.
+        * systty.h (SIGIO): Do not #undef here; it's now syssignal.h's job.
+        This eliminates a problem whereby other files mysteriously had
+        to include "syssignal.h" before including "systty.h" if they
+        wanted to use "#ifdef SIGIO".
+
 2012-09-07  Eli Zaretskii  <eliz@gnu.org>
 
         * w32proc.c (sigaction): New function, emulates Posix 'sigaction'.
diff --git a/src/floatfns.c b/src/floatfns.c
index e956dc22353..3a95d828c0c 100644
--- a/src/floatfns.c
+++ b/src/floatfns.c
@@ -38,7 +38,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    This has no effect if HAVE_MATHERR is defined.
 
    Define FLOAT_CHECK_DOMAIN if the float library doesn't handle errors by
-   either setting errno, or signaling SIGFPE/SIGILL.  Otherwise, domain and
+   either setting errno, or signaling SIGFPE.  Otherwise, domain and
    range checking will happen before calling the float routines.  This has
    no effect if HAVE_MATHERR is defined (since matherr will be called when
    a domain error occurs.)
diff --git a/src/lisp.h b/src/lisp.h
index 28e8c1cd1e8..e6594b5890c 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -3221,9 +3221,7 @@ extern void cmd_error_internal (Lisp_Object, const char *);
 extern Lisp_Object command_loop_1 (void);
 extern Lisp_Object recursive_edit_1 (void);
 extern void record_auto_save (void);
-#ifdef SIGDANGER
 extern void force_auto_save_soon (void);
-#endif
 extern void init_keyboard (void);
 extern void syms_of_keyboard (void);
 extern void keys_of_keyboard (void);
diff --git a/src/syssignal.h b/src/syssignal.h
index fe7b5f0e150..c5529ae718a 100644
--- a/src/syssignal.h
+++ b/src/syssignal.h
@@ -38,9 +38,12 @@ extern void emacs_sigaction_init (struct sigaction *, signal_handler_t);
 _Noreturn void croak (char *);
 #endif
 
-#if defined (SIGIO) && defined (BROKEN_SIGIO)
+/* Interrupt input is not used if there is no FIONREAD.  */
+#include <sys/ioctl.h>
+#if defined BROKEN_SIGIO || ! defined FIONREAD || defined BROKEN_FIONREAD
 # undef SIGIO
 #endif
+
 /* These are only used by AIX  */
 #if defined (SIGPOLL) && defined (BROKEN_SIGPOLL)
 #undef SIGPOLL
diff --git a/src/systty.h b/src/systty.h
index ae98f123f2a..b660441a91e 100644
--- a/src/systty.h
+++ b/src/systty.h
@@ -47,11 +47,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #undef ASYNC
 #endif
 
-/* Interrupt input is not used if there is no FIONREAD.  */
-#ifndef FIONREAD
-#undef SIGIO
-#endif
-
 
 /* Try to establish the correct character to disable terminal functions
    in a system-independent manner.  Note that USG (at least) define