Fix standards conformance bugs in <signal.h>:

include/signal.h:
There was massive namespace pollution from including <sys/types.h>.
POSIX functions were declared even when _ANSI_SOURCE is defined.

sys.sys/signal.h:
NSIG was declared even if _ANSI_SOURCE or _POSIX_SOURCE is defined.
sig_atomic_t wasn't declared if _POSIX_SOURCE is defined.
Declare a typedef for signal handling functions and use it to
unobfuscate declarations and to avoid half-baked function types
that cause unwanted compiler warnings at certain warning levels.
Fix confusing comment about SA_RESTART.

sys/i386/include/signal.h:
This has to be included to get the declaration of sig_atomic_t even
when _ANSI_SOURCE is defined, so be more careful about polluting
the ANSI namespace.

Uniformize idempotency ifdefs.

5 files changed, 86 insertions, 66 deletions

diff --git a/include/signal.h b/include/signal.h
index 6bb7ddf..d8ebeee 100644
--- a/include/signal.h
+++ b/include/signal.h
@@ -33,12 +33,12 @@
  *	@(#)signal.h	8.3 (Berkeley) 3/30/94
  */
 
-#ifndef _USER_SIGNAL_H
-#define _USER_SIGNAL_H
+#ifndef _SIGNAL_H_
+#define	_SIGNAL_H_
 
-#include <sys/types.h>
 #include <sys/cdefs.h>
 #include <sys/signal.h>
+#include <machine/ansi.h>
 
 #if !defined(_ANSI_SOURCE) && !defined(_POSIX_SOURCE)
 extern __const char *__const sys_signame[NSIG];
@@ -48,7 +48,7 @@ extern __const char *__const sys_siglist[NSIG];
 __BEGIN_DECLS
 int	raise __P((int));
 #ifndef	_ANSI_SOURCE
-int	kill __P((pid_t, int));
+int	kill __P((_BSD_PID_T_, int));
 int	sigaction __P((int, const struct sigaction *, struct sigaction *));
 int	sigaddset __P((sigset_t *, int));
 int	sigdelset __P((sigset_t *, int));
@@ -59,7 +59,7 @@ int	sigpending __P((sigset_t *));
 int	sigprocmask __P((int, const sigset_t *, sigset_t *));
 int	sigsuspend __P((const sigset_t *));
 #ifndef _POSIX_SOURCE
-int	killpg __P((pid_t, int));
+int	killpg __P((_BSD_PID_T_, int));
 int	sigblock __P((int));
 int	siginterrupt __P((int, int));
 int	sigpause __P((int));
@@ -68,15 +68,17 @@ int	sigsetmask __P((int));
 int	sigstack __P((const struct sigstack *, struct sigstack *));
 int	sigvec __P((int, struct sigvec *, struct sigvec *));
 void	psignal __P((unsigned int, const char *));
-#endif	/* !_POSIX_SOURCE */
-#endif	/* !_ANSI_SOURCE */
+#endif /* !_POSIX_SOURCE */
+#endif /* !_ANSI_SOURCE */
 __END_DECLS
 
+#ifndef _ANSI_SOURCE
 /* List definitions after function declarations, or Reiser cpp gets upset. */
 #define	sigaddset(set, signo)	(*(set) |= 1 << ((signo) - 1), 0)
 #define	sigdelset(set, signo)	(*(set) &= ~(1 << ((signo) - 1)), 0)
 #define	sigemptyset(set)	(*(set) = 0, 0)
 #define	sigfillset(set)		(*(set) = ~(sigset_t)0, 0)
 #define	sigismember(set, signo)	((*(set) & (1 << ((signo) - 1))) != 0)
+#endif /* !_ANSI_SOURCE */
 
-#endif	/* !_USER_SIGNAL_H */
+#endif /* !_SIGNAL_H_ */
diff --git a/sys/amd64/include/signal.h b/sys/amd64/include/signal.h
index 093278f..628a236 100644
--- a/sys/amd64/include/signal.h
+++ b/sys/amd64/include/signal.h
@@ -31,11 +31,11 @@
  * SUCH DAMAGE.
  *
  *	@(#)signal.h	8.1 (Berkeley) 6/11/93
- * $Id: signal.h,v 1.3 1994/08/02 07:39:01 davidg Exp $
+ * $Id: signal.h,v 1.4 1994/08/21 04:55:30 paul Exp $
  */
 
-#ifndef _I386_MACHINE_SIGNAL_H_
-#define _I386_MACHINE_SIGNAL_H_
+#ifndef _MACHINE_SIGNAL_H_
+#define	_MACHINE_SIGNAL_H_
 
 /*
  * Machine-dependent signal definitions
@@ -43,9 +43,9 @@
 
 typedef int sig_atomic_t;
 
-#ifndef _POSIX_SOURCE
+#if !defined(_ANSI_SOURCE) && !defined(_POSIX_SOURCE)
+
 #include <machine/trap.h>	/* codes for SIGILL, SIGFPE */
-#endif
 
 /*
  * Information pushed on stack when a signal is delivered.
@@ -78,4 +78,6 @@ struct	sigcontext {
 #  define sc_ps sc_efl
 };
 
-#endif
+#endif /* !_ANSI_SOURCE && !_POSIX_SOURCE */
+
+#endif /* !_MACHINE_SIGNAL_H_ */
diff --git a/sys/i386/include/signal.h b/sys/i386/include/signal.h
index 093278f..628a236 100644
--- a/sys/i386/include/signal.h
+++ b/sys/i386/include/signal.h
@@ -31,11 +31,11 @@
  * SUCH DAMAGE.
  *
  *	@(#)signal.h	8.1 (Berkeley) 6/11/93
- * $Id: signal.h,v 1.3 1994/08/02 07:39:01 davidg Exp $
+ * $Id: signal.h,v 1.4 1994/08/21 04:55:30 paul Exp $
  */
 
-#ifndef _I386_MACHINE_SIGNAL_H_
-#define _I386_MACHINE_SIGNAL_H_
+#ifndef _MACHINE_SIGNAL_H_
+#define	_MACHINE_SIGNAL_H_
 
 /*
  * Machine-dependent signal definitions
@@ -43,9 +43,9 @@
 
 typedef int sig_atomic_t;
 
-#ifndef _POSIX_SOURCE
+#if !defined(_ANSI_SOURCE) && !defined(_POSIX_SOURCE)
+
 #include <machine/trap.h>	/* codes for SIGILL, SIGFPE */
-#endif
 
 /*
  * Information pushed on stack when a signal is delivered.
@@ -78,4 +78,6 @@ struct	sigcontext {
 #  define sc_ps sc_efl
 };
 
-#endif
+#endif /* !_ANSI_SOURCE && !_POSIX_SOURCE */
+
+#endif /* !_MACHINE_SIGNAL_H_ */
diff --git a/sys/sys/_sigset.h b/sys/sys/_sigset.h
index c26054b..515a00d 100644
--- a/sys/sys/_sigset.h
+++ b/sys/sys/_sigset.h
@@ -36,16 +36,17 @@
  * SUCH DAMAGE.
  *
  *	@(#)signal.h	8.2 (Berkeley) 1/21/94
- * $Id: signal.h,v 1.2 1994/08/02 07:53:32 davidg Exp $
+ * $Id: signal.h,v 1.3 1995/01/29 01:19:25 ats Exp $
  */
 
 #ifndef	_SYS_SIGNAL_H_
 #define	_SYS_SIGNAL_H_
 
-#define NSIG	32		/* counting 0; could be 33 (mask is 1-32) */
+#include <sys/cdefs.h>
+#include <machine/signal.h>	/* sig_atomic_t; trap codes; sigcontext */
 
-#ifndef _ANSI_SOURCE
-#include <machine/signal.h>	/* sigcontext; codes for SIGILL, SIGFPE */
+#if !defined(_ANSI_SOURCE) && !defined(_POSIX_SOURCE)
+#define NSIG	32		/* counting 0; could be 33 (mask is 1-32) */
 #endif
 
 #define	SIGHUP	1	/* hangup */
@@ -93,19 +94,27 @@
 #define SIGUSR1 30	/* user defined signal 1 */
 #define SIGUSR2 31	/* user defined signal 2 */
 
-#if defined(_ANSI_SOURCE) || defined(__cplusplus)
-/*
- * Language spec sez we must list exactly one parameter, even though we
+/*-
+ * Type of a signal handling function.
+ *
+ * Language spec sez signal handlers take exactly one arg, even though we
  * actually supply three.  Ugh!
+ *
+ * We don't try to hide the difference by leaving out the args because
+ * that would cause warnings about conformant programs.  Nonconformant
+ * programs can avoid the warnings by casting to (__sighandler_t *) or
+ * sig_t before calling signal() or assigning to sa_handler or sv_handler.
+ *
+ * The kernel should reverse the cast before calling the function.  It
+ * has no way to do this, but on most machines 1-arg and 3-arg functions
+ * have the same calling protocol so there is no problem in practice.
+ * A bit in sa_flags could be used to specify the number of args.
  */
-#define	SIG_DFL		(void (*)(int))0
-#define	SIG_IGN		(void (*)(int))1
-#define	SIG_ERR		(void (*)(int))-1
-#else
-#define	SIG_DFL		(void (*)())0
-#define	SIG_IGN		(void (*)())1
-#define	SIG_ERR		(void (*)())-1
-#endif
+typedef void __sighandler_t __P((int));
+
+#define	SIG_DFL		((__sighandler_t *)0)
+#define	SIG_IGN		((__sighandler_t *)1)
+#define	SIG_ERR		((__sighandler_t *)-1)
 
 #ifndef _ANSI_SOURCE
 typedef unsigned int sigset_t;
@@ -114,13 +123,13 @@ typedef unsigned int sigset_t;
  * Signal vector "template" used in sigaction call.
  */
 struct	sigaction {
-	void	(*sa_handler)();	/* signal handler */
+	__sighandler_t *sa_handler;	/* signal handler */
 	sigset_t sa_mask;		/* signal mask to apply */
 	int	sa_flags;		/* see signal options below */
 };
 #ifndef _POSIX_SOURCE
 #define SA_ONSTACK	0x0001	/* take signal on signal stack */
-#define SA_RESTART	0x0002	/* restart system on signal return */
+#define SA_RESTART	0x0002	/* restart system call on signal return */
 #define	SA_DISABLE	0x0004	/* disable taking signals on alternate stack */
 #ifdef COMPAT_SUNOS
 #define	SA_USERTRAMP	0x0100	/* do not bounce off kernel's sigtramp */
@@ -136,10 +145,7 @@ struct	sigaction {
 #define	SIG_SETMASK	3	/* set specified signal set */
 
 #ifndef _POSIX_SOURCE
-#ifndef KERNEL
-#include <sys/cdefs.h>
-#endif
-typedef	void (*sig_t) __P((int));	/* type of signal function */
+typedef	__sighandler_t	*sig_t;	/* type of pointer to a signal function */
 
 /*
  * Structure used in sigaltstack call.
@@ -157,7 +163,7 @@ struct	sigaltstack {
  * Signal vector "template" used in sigvec call.
  */
 struct	sigvec {
-	void	(*sv_handler)();	/* signal handler */
+	__sighandler_t *sv_handler;	/* signal handler */
 	int	sv_mask;		/* signal mask to apply */
 	int	sv_flags;		/* see signal options below */
 };
@@ -190,6 +196,7 @@ struct	sigstack {
  * defined by <sys/signal.h>.
  */
 __BEGIN_DECLS
-void	(*signal __P((int, void (*) __P((int))))) __P((int));
+__sighandler_t *signal __P((int, __sighandler_t *));
 __END_DECLS
+
 #endif	/* !_SYS_SIGNAL_H_ */
diff --git a/sys/sys/signal.h b/sys/sys/signal.h
index c26054b..515a00d 100644
--- a/sys/sys/signal.h
+++ b/sys/sys/signal.h
@@ -36,16 +36,17 @@
  * SUCH DAMAGE.
  *
  *	@(#)signal.h	8.2 (Berkeley) 1/21/94
- * $Id: signal.h,v 1.2 1994/08/02 07:53:32 davidg Exp $
+ * $Id: signal.h,v 1.3 1995/01/29 01:19:25 ats Exp $
  */
 
 #ifndef	_SYS_SIGNAL_H_
 #define	_SYS_SIGNAL_H_
 
-#define NSIG	32		/* counting 0; could be 33 (mask is 1-32) */
+#include <sys/cdefs.h>
+#include <machine/signal.h>	/* sig_atomic_t; trap codes; sigcontext */
 
-#ifndef _ANSI_SOURCE
-#include <machine/signal.h>	/* sigcontext; codes for SIGILL, SIGFPE */
+#if !defined(_ANSI_SOURCE) && !defined(_POSIX_SOURCE)
+#define NSIG	32		/* counting 0; could be 33 (mask is 1-32) */
 #endif
 
 #define	SIGHUP	1	/* hangup */
@@ -93,19 +94,27 @@
 #define SIGUSR1 30	/* user defined signal 1 */
 #define SIGUSR2 31	/* user defined signal 2 */
 
-#if defined(_ANSI_SOURCE) || defined(__cplusplus)
-/*
- * Language spec sez we must list exactly one parameter, even though we
+/*-
+ * Type of a signal handling function.
+ *
+ * Language spec sez signal handlers take exactly one arg, even though we
  * actually supply three.  Ugh!
+ *
+ * We don't try to hide the difference by leaving out the args because
+ * that would cause warnings about conformant programs.  Nonconformant
+ * programs can avoid the warnings by casting to (__sighandler_t *) or
+ * sig_t before calling signal() or assigning to sa_handler or sv_handler.
+ *
+ * The kernel should reverse the cast before calling the function.  It
+ * has no way to do this, but on most machines 1-arg and 3-arg functions
+ * have the same calling protocol so there is no problem in practice.
+ * A bit in sa_flags could be used to specify the number of args.
  */
-#define	SIG_DFL		(void (*)(int))0
-#define	SIG_IGN		(void (*)(int))1
-#define	SIG_ERR		(void (*)(int))-1
-#else
-#define	SIG_DFL		(void (*)())0
-#define	SIG_IGN		(void (*)())1
-#define	SIG_ERR		(void (*)())-1
-#endif
+typedef void __sighandler_t __P((int));
+
+#define	SIG_DFL		((__sighandler_t *)0)
+#define	SIG_IGN		((__sighandler_t *)1)
+#define	SIG_ERR		((__sighandler_t *)-1)
 
 #ifndef _ANSI_SOURCE
 typedef unsigned int sigset_t;
@@ -114,13 +123,13 @@ typedef unsigned int sigset_t;
  * Signal vector "template" used in sigaction call.
  */
 struct	sigaction {
-	void	(*sa_handler)();	/* signal handler */
+	__sighandler_t *sa_handler;	/* signal handler */
 	sigset_t sa_mask;		/* signal mask to apply */
 	int	sa_flags;		/* see signal options below */
 };
 #ifndef _POSIX_SOURCE
 #define SA_ONSTACK	0x0001	/* take signal on signal stack */
-#define SA_RESTART	0x0002	/* restart system on signal return */
+#define SA_RESTART	0x0002	/* restart system call on signal return */
 #define	SA_DISABLE	0x0004	/* disable taking signals on alternate stack */
 #ifdef COMPAT_SUNOS
 #define	SA_USERTRAMP	0x0100	/* do not bounce off kernel's sigtramp */
@@ -136,10 +145,7 @@ struct	sigaction {
 #define	SIG_SETMASK	3	/* set specified signal set */
 
 #ifndef _POSIX_SOURCE
-#ifndef KERNEL
-#include <sys/cdefs.h>
-#endif
-typedef	void (*sig_t) __P((int));	/* type of signal function */
+typedef	__sighandler_t	*sig_t;	/* type of pointer to a signal function */
 
 /*
  * Structure used in sigaltstack call.
@@ -157,7 +163,7 @@ struct	sigaltstack {
  * Signal vector "template" used in sigvec call.
  */
 struct	sigvec {
-	void	(*sv_handler)();	/* signal handler */
+	__sighandler_t *sv_handler;	/* signal handler */
 	int	sv_mask;		/* signal mask to apply */
 	int	sv_flags;		/* see signal options below */
 };
@@ -190,6 +196,7 @@ struct	sigstack {
  * defined by <sys/signal.h>.
  */
 __BEGIN_DECLS
-void	(*signal __P((int, void (*) __P((int))))) __P((int));
+__sighandler_t *signal __P((int, __sighandler_t *));
 __END_DECLS
+
 #endif	/* !_SYS_SIGNAL_H_ */