From b67de6ba172135076b3933578bf51e6966f623ec Mon Sep 17 00:00:00 2001
From: tg <tg@mirbsd.org>
Date: Fri, 27 Apr 2012 16:16:23 +0000
Subject: [PATCH] add experimental code to use sigprocmask+pause+sigprocmask
 ipv sigsuspend (and harden j_sigchld handler for that) to improve working on
 BeOS 5.0 and Coherent UNIX, found by RT

---
 Build.sh |  5 +++--
 check.t  |  4 ++--
 jobs.c   | 28 +++++++++++++++++++++++++---
 sh.h     |  4 ++--
 4 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/Build.sh b/Build.sh
index 84d1f7c..34cc670 100644
--- a/Build.sh
+++ b/Build.sh
@@ -1,5 +1,5 @@
 #!/bin/sh
-srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.551 2012/04/16 17:49:40 tg Exp $'
+srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.552 2012/04/27 16:16:19 tg Exp $'
 #-
 # Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
 #		2011, 2012
@@ -1398,7 +1398,7 @@ else
 		#define EXTERN
 		#define MKSH_INCLUDES_ONLY
 		#include "sh.h"
-		__RCSID("$MirOS: src/bin/mksh/Build.sh,v 1.551 2012/04/16 17:49:40 tg Exp $");
+		__RCSID("$MirOS: src/bin/mksh/Build.sh,v 1.552 2012/04/27 16:16:19 tg Exp $");
 		int main(void) { printf("Hello, World!\n"); return (0); }
 EOF
 	case $cm in
@@ -2096,6 +2096,7 @@ MKSH_NO_DEPRECATED_WARNING	omit warning when deprecated stuff is run
 MKSH_NO_EXTERNAL_CAT		omit hack to skip cat builtin when flags passed
 MKSH_NO_LIMITS			omit ulimit code
 MKSH_NO_SIGSETJMP		define if sigsetjmp is broken or not available
+MKSH_NO_SIGSUSPEND		use sigprocmask+pause instead of sigsuspend
 MKSH_SMALL			omit some code, optimise hard for size (slower)
 MKSH_S_NOVI=1			disable Vi editing mode (default if MKSH_SMALL)
 MKSH_TYPEDEF_SIG_ATOMIC_T	define to e.g. 'int' if sig_atomic_t is missing
diff --git a/check.t b/check.t
index fd28e6b..b617e69 100644
--- a/check.t
+++ b/check.t
@@ -1,4 +1,4 @@
-# $MirOS: src/bin/mksh/check.t,v 1.533 2012/04/22 21:50:29 tg Exp $
+# $MirOS: src/bin/mksh/check.t,v 1.534 2012/04/27 16:16:21 tg Exp $
 # $OpenBSD: bksl-nl.t,v 1.2 2001/01/28 23:04:56 niklas Exp $
 # $OpenBSD: history.t,v 1.5 2001/01/28 23:04:56 niklas Exp $
 # $OpenBSD: read.t,v 1.3 2003/03/10 03:48:16 david Exp $
@@ -29,7 +29,7 @@
 # http://www.freebsd.org/cgi/cvsweb.cgi/src/tools/regression/bin/test/regress.sh?rev=HEAD
 
 expected-stdout:
-	@(#)MIRBSD KSH R40 2012/04/22
+	@(#)MIRBSD KSH R40 2012/04/27
 description:
 	Check version of shell.
 stdin:
diff --git a/jobs.c b/jobs.c
index bb38997..c04ebd2 100644
--- a/jobs.c
+++ b/jobs.c
@@ -22,7 +22,7 @@
 
 #include "sh.h"
 
-__RCSID("$MirOS: src/bin/mksh/jobs.c,v 1.84 2012/02/06 17:49:52 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/jobs.c,v 1.85 2012/04/27 16:16:22 tg Exp $");
 
 #if HAVE_KILLPG
 #define mksh_killpg		killpg
@@ -1062,6 +1062,9 @@ j_waitj(Job *j,
     const char *where)
 {
 	int rv;
+#ifdef MKSH_NO_SIGSUSPEND
+	sigset_t omask;
+#endif
 
 	/*
 	 * No auto-notify on the job we are waiting on.
@@ -1078,7 +1081,14 @@ j_waitj(Job *j,
 	while (j->state == PRUNNING ||
 	    ((flags & JW_STOPPEDWAIT) && j->state == PSTOPPED)) {
 #ifndef MKSH_NOPROSPECTOFWORK
+#ifdef MKSH_NO_SIGSUSPEND
+		sigprocmask(SIG_SETMASK, &sm_default, &omask);
+		pause();
+		/* note that handlers may run here so they need to know */
+		sigprocmask(SIG_SETMASK, &qmask, NULL);
+#else
 		sigsuspend(&sm_default);
+#endif
 #else
 		j_sigchld(SIGCHLD);
 #endif
@@ -1244,6 +1254,12 @@ j_sigchld(int sig MKSH_A_UNUSED)
 	pid_t pid;
 	int status;
 	struct rusage ru0, ru1;
+#ifdef MKSH_NO_SIGSUSPEND
+	sigset_t omask;
+
+	/* this handler can run while SIGCHLD is not blocked, so block it now */
+	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
+#endif
 
 #ifndef MKSH_NOPROSPECTOFWORK
 	/*
@@ -1255,7 +1271,7 @@ j_sigchld(int sig MKSH_A_UNUSED)
 	for (j = job_list; j; j = j->next)
 		if (j->ppid == procpid && !(j->flags & JF_STARTED)) {
 			held_sigchld = 1;
-			return;
+			goto j_sigchld_out;
 		}
 #endif
 
@@ -1272,7 +1288,7 @@ j_sigchld(int sig MKSH_A_UNUSED)
 		 * or interrupted (-1)
 		 */
 		if (pid <= 0)
-			return;
+			goto j_sigchld_out;
 
 		getrusage(RUSAGE_CHILDREN, &ru1);
 
@@ -1315,6 +1331,12 @@ j_sigchld(int sig MKSH_A_UNUSED)
 #else
 	    while (/* CONSTCOND */ 0);
 #endif
+
+ j_sigchld_out:
+#ifdef MKSH_NO_SIGSUSPEND
+	sigprocmask(SIG_SETMASK, &omask, NULL);
+#endif
+	/* nothing */;
 }
 
 /*
diff --git a/sh.h b/sh.h
index 996f1aa..16e621e 100644
--- a/sh.h
+++ b/sh.h
@@ -152,9 +152,9 @@
 #endif
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.550 2012/04/22 21:50:33 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.551 2012/04/27 16:16:23 tg Exp $");
 #endif
-#define MKSH_VERSION "R40 2012/04/22"
+#define MKSH_VERSION "R40 2012/04/27"
 
 /* arithmetic types: C implementation */
 #if !HAVE_CAN_INTTYPES