Don't do signal blocking; simply set a semaphore flag indicating it is

in critical code, and let the main loop deal with the flag being set.
This saves on context switches into the kernel for this rare condition.

1 files changed, 26 insertions, 115 deletions

diff --git a/server/uloc.c b/server/uloc.c
index fcf283b..9c4984c 100644
--- a/server/uloc.c
+++ b/server/uloc.c
@@ -438,22 +438,11 @@ uloc_hflush(addr)
 {
 	ZLocation_t *loc;
 	register int i = 0, new_num = 0;
-#ifdef POSIX
-	sigset_t mask, omask;
-#else
-	int omask;
-#endif
 
 	if (num_locs == 0)
 	    return;			/* none to flush */
 
-#ifdef POSIX
-	sigemptyset(&mask);
-	sigaddset(&mask, SIGFPE);
-	sigprocmask(SIG_BLOCK, &mask, &omask);
-#else
-	omask = sigblock(sigmask(SIGFPE));	/* don't let db dumps start */
-#endif
+	START_CRITICAL_CODE;
 
 	/* slightly inefficient, assume the worst, and allocate enough space */
 	loc = (ZLocation_t *) xmalloc(num_locs *sizeof(ZLocation_t));
@@ -490,21 +479,16 @@ uloc_hflush(addr)
 		xfree(loc);
 		loc = NULLZLT;
 		num_locs = new_num;
-#ifdef POSIX
-		(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-		(void) sigsetmask(omask);
-#endif
+
+		END_CRITICAL_CODE;
+
 		return;
 	}
 	locations = loc;
 	num_locs = new_num;
 
-#ifdef POSIX
-	(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-	(void) sigsetmask(omask);
-#endif
+	END_CRITICAL_CODE;
+
 	/* all done */
 	return;
 }
@@ -515,22 +499,11 @@ uloc_flush_client(sin)
 {
 	ZLocation_t *loc;
 	register int i = 0, new_num = 0;
-#ifdef POSIX
-	sigset_t mask, omask;
-#else
-	int omask;
-#endif
 
 	if (num_locs == 0)
 	    return;			/* none to flush */
 
-#ifdef POSIX
-	sigemptyset(&mask);
-	sigaddset(&mask, SIGFPE);
-	sigprocmask(SIG_BLOCK, &mask, &omask);
-#else
-	omask = sigblock(sigmask(SIGFPE));	/* don't let db dumps start */
-#endif
+	START_CRITICAL_CODE;
 
 	/* slightly inefficient, assume the worst, and allocate enough space */
 	loc = (ZLocation_t *) xmalloc(num_locs *sizeof(ZLocation_t));
@@ -568,21 +541,16 @@ uloc_flush_client(sin)
 		xfree(loc);
 		loc = NULLZLT;
 		num_locs = new_num;
-#ifdef POSIX
-		(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-		(void) sigsetmask(omask);
-#endif
+
+		END_CRITICAL_CODE;
+
 		return;
 	}
 	locations = loc;
 	num_locs = new_num;
 
-#ifdef POSIX
-	(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-	(void) sigsetmask(omask);
-#endif
+	END_CRITICAL_CODE;
+
 #ifdef DEBUG
 	if (zdebug) {
 		register int i;
@@ -670,11 +638,6 @@ ulogin_add_user(notice, exposure, who)
 {
 	ZLocation_t *oldlocs, newloc;
 	register int i;
-#ifdef POSIX
-	sigset_t mask, omask;
-#else
-	int omask;
-#endif
 
 	if ((oldlocs = ulogin_find(notice,1)) != NULLZLT) {
 #if 0
@@ -686,13 +649,8 @@ ulogin_add_user(notice, exposure, who)
 
 	oldlocs = locations;
 
-#ifdef POSIX
-	sigemptyset(&mask);
-	sigaddset(&mask, SIGFPE);
-	sigprocmask(SIG_BLOCK, &mask, &omask);
-#else
-	omask = sigblock(sigmask(SIGFPE));	/* don't let db dumps start */
-#endif
+	START_CRITICAL_CODE;
+	
 	locations = (ZLocation_t *) xmalloc((num_locs +1) *
 					    sizeof(ZLocation_t));
 	if (!locations) {
@@ -705,11 +663,7 @@ ulogin_add_user(notice, exposure, who)
 		if (ulogin_setup(notice, locations, exposure, who)) {
 		  xfree(locations);
 		  locations = NULLZLT;
-#ifdef POSIX
-		  (void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-		  (void) sigsetmask(omask);
-#endif
+		  END_CRITICAL_CODE;
 		  return 1;
 		}
 		num_locs = 1;
@@ -721,11 +675,7 @@ ulogin_add_user(notice, exposure, who)
 	if (ulogin_setup(notice, &newloc, exposure, who)) {
 		xfree(locations);
 		locations = oldlocs;
-#ifdef POSIX
-		(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-		(void) sigsetmask(omask);
-#endif
+		END_CRITICAL_CODE;
 		return 1;
 	}
 	num_locs++;
@@ -762,11 +712,7 @@ ulogin_add_user(notice, exposure, who)
 			       (int) locations[i].zlt_exposure);
 	}
 #endif
-#ifdef POSIX
-	(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-	(void) sigsetmask(omask);
-#endif
+	END_CRITICAL_CODE;
 	return 0;
 }
 
@@ -990,11 +936,6 @@ ulogin_remove_user(notice, auth, who, err_return)
 	ZLocation_t *loc, *loc2;
 	register int i = 0;
 	exposure_type quiet;
-#ifdef POSIX
-	sigset_t mask, omask;
-#else
-	int omask;
-#endif
 
 	*err_return = 0;
 	if (!(loc2 = ulogin_find(notice, 1))) {
@@ -1014,13 +955,7 @@ ulogin_remove_user(notice, auth, who, err_return)
 
 	quiet = loc2->zlt_exposure;
 
-#ifdef POSIX
-	sigemptyset(&mask);
-	sigaddset(&mask, SIGFPE);
-	sigprocmask(SIG_BLOCK, &mask, &omask);
-#else
-	omask = sigblock(sigmask(SIGFPE));	/* don't let db dumps start */
-#endif
+	START_CRITICAL_CODE;
 	if (--num_locs == 0) {		/* last one */
 #if 0
 		zdbug((LOG_DEBUG,"last loc"));
@@ -1028,11 +963,7 @@ ulogin_remove_user(notice, auth, who, err_return)
 		free_loc(locations);
 		xfree(locations);
 		locations = NULLZLT;
-#ifdef POSIX
-		(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-		(void) sigsetmask(omask);
-#endif
+		END_CRITICAL_CODE;
 		return(quiet);
 	}
 
@@ -1063,11 +994,8 @@ ulogin_remove_user(notice, auth, who, err_return)
 
 	locations = loc;
 
-#ifdef POSIX
-	(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-	(void) sigsetmask(omask);
-#endif
+	END_CRITICAL_CODE;
+
 #if defined(DEBUG) && 0
 	if (zdebug) {
 		register int i;
@@ -1092,11 +1020,6 @@ ulogin_flush_user(notice)
 {
 	register ZLocation_t *loc, *loc2;
 	register int i, j, num_match, num_left;
-#ifdef POSIX
-	sigset_t mask, omask;
-#else
-	int omask;
-#endif
 
 	i = num_match = num_left = 0;
 
@@ -1110,13 +1033,8 @@ ulogin_flush_user(notice)
 	/* compute # locations left in the list, after loc2 (inclusive) */
 	num_left = num_locs - (loc2 - locations);
 
-#ifdef POSIX
-	sigemptyset(&mask);
-	sigaddset(&mask, SIGFPE);
-	sigprocmask(SIG_BLOCK, &mask, &omask);
-#else
-	omask = sigblock(sigmask(SIGFPE));	/* don't let db dumps start */
-#endif
+	START_CRITICAL_CODE;
+
 	while (num_left &&
 	       !strcasecmp(loc2[num_match].zlt_user->string,
 		       notice->z_class_inst)) {
@@ -1133,11 +1051,7 @@ ulogin_flush_user(notice)
 		xfree (locations);
 		locations = NULLZLT;
 		num_locs = 0;
-#ifdef POSIX
-		(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-		(void) sigsetmask(omask);
-#endif
+		END_CRITICAL_CODE;
 		return;
 	}
 
@@ -1171,11 +1085,8 @@ ulogin_flush_user(notice)
 	locations = loc;
 	num_locs -= num_match;
 
-#ifdef POSIX
-	(void) sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
-#else
-	(void) sigsetmask(omask);
-#endif
+	END_CRITICAL_CODE;
+	
 #ifdef DEBUG
 	if (zdebug) {
 		register int i;