sh: Successfully do nothing when killing a terminated job.

If a job has terminated but is still known, silently do nothing when using
the kill builtin with the job specifier. Formerly, the shell called kill()
with the process group ID that might have been reused.

4 files changed, 19 insertions, 2 deletions

diff --git a/bin/kill/kill.c b/bin/kill/kill.c
index 2d41f78..ab1701e 100644
--- a/bin/kill/kill.c
+++ b/bin/kill/kill.c
@@ -133,9 +133,15 @@ main(int argc, char *argv[])
 
 	for (errors = 0; argc; argc--, argv++) {
 #ifdef SHELL
-		if (**argv == '%')
+		if (**argv == '%') {
 			pid = getjobpgrp(*argv);
-		else
+			/*
+			 * Silently ignore terminated jobs, like the kernel
+			 * silently ignores zombies.
+			 */
+			if (pid == 0)
+				continue;
+		} else
 #endif
 		{
 			pid = strtol(*argv, &ep, 10);
diff --git a/bin/sh/jobs.c b/bin/sh/jobs.c
index 1c0c6bd..6e7791c 100644
--- a/bin/sh/jobs.c
+++ b/bin/sh/jobs.c
@@ -645,6 +645,8 @@ getjobpgrp(char *name)
 	struct job *jp;
 
 	jp = getjob(name);
+	if (jp->state == JOBDONE)
+		return 0;
 	return -jp->ps[0].pid;
 }
 
diff --git a/bin/sh/tests/builtins/Makefile b/bin/sh/tests/builtins/Makefile
index 6f60f84..b76d631 100644
--- a/bin/sh/tests/builtins/Makefile
+++ b/bin/sh/tests/builtins/Makefile
@@ -86,6 +86,7 @@ FILES+=		hash3.0 hash3.0.stdout
 FILES+=		hash4.0
 FILES+=		jobid1.0
 FILES+=		jobid2.0
+FILES+=		kill1.0
 FILES+=		lineno.0 lineno.0.stdout
 FILES+=		lineno2.0
 FILES+=		local1.0
diff --git a/bin/sh/tests/builtins/kill1.0 b/bin/sh/tests/builtins/kill1.0
new file mode 100644
index 0000000..c1b8550
--- /dev/null
+++ b/bin/sh/tests/builtins/kill1.0
@@ -0,0 +1,8 @@
+# $FreeBSD$
+
+: &
+p1=$!
+: &
+p2=$!
+wait $p2
+kill %1