qa: check devproc start/stop ctl msg

qa/kern/build.json

@@ -36,6 +36,7 @@
 			"psx.c",
 			"segattach.c",
 			"sched0.c",
+			"stop_start.c",
 			"syscall.c",
 			"sysstatread.c",
 			"tsemacquire.c",

qa/kern/stop_start.c

@@ -0,0 +1,41 @@
+/*
+ * This file is part of Jehanne.
+ *
+ * Copyright (C) 2017 Giacomo Tesio <giacomo@tesio.it>
+ *
+ * Jehanne is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * Jehanne is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jehanne.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <u.h>
+#include <lib9.h>
+
+void
+main(int argc, char**argv)
+{
+	int fd, n;
+	char *path;
+	
+	path = smprint("/proc/%d/ctl", getpid());
+	fd = open(path, OWRITE);
+	if(fd < 0){
+		print("FAIL: open");
+		exits("FAIL");
+	}
+	n = write(fd, "stop", 4);
+	if(n < 0){
+		print("FAIL: write");
+		exits("FAIL");
+	}
+	close(fd);
+	print("PASS\n");
+	exits("PASS");
+}

qa/kern/stop_start.runner

@@ -0,0 +1,29 @@
+#!/cmd/rc
+
+runner=$0
+test = `{echo $runner|sed 's/.runner//'}
+test_output = /tmp/output-`{basename $test}
+
+if ( test -e $test_output) rm $test_output
+
+$test > $test_output &
+testpid=$apid
+sleep 5
+
+if ( cat $test_output | grep 'PASS' > /dev/null ) {
+	cat $test_output
+	echo FAIL
+	exit FAIL
+}
+
+echo start > /proc/$testpid/ctl
+wait $testpid
+
+if ( cat $test_output | grep 'PASS' > /dev/null ) {
+	rm $test_output
+	echo PASS
+	exit PASS
+}
+cat $test_output
+echo FAIL
+exit FAIL