From a52543acd2b6713f679f91f8f92bc0744b303f94 Mon Sep 17 00:00:00 2001
From: Christian Helmuth <christian.helmuth@genode-labs.com>
Date: Sat, 17 Dec 2016 14:05:57 +0100
Subject: [PATCH] Improve noux fork test (grand child, waitpid)

The test now forks twice - the parent forks a child and the child itself
forks a grand child. Both, parent and child, wait for termination of
their forked process with waitpid(). Additionally, the run script now
checks for exit of the parent (not any noux process).
---
 repos/ports/run/noux_fork.run          | 12 +++++---
 repos/ports/src/test/noux_fork/test.cc | 39 +++++++++++++++++++++++---
 2 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/repos/ports/run/noux_fork.run b/repos/ports/run/noux_fork.run
index d831b8e2dd..3f0667ae1f 100644
--- a/repos/ports/run/noux_fork.run
+++ b/repos/ports/run/noux_fork.run
@@ -30,9 +30,12 @@ install_config {
 			<provides><service name="Terminal"/></provides>
 		</start>
 		<start name="noux">
-			<resource name="RAM" quantum="1G"/>
-			<config verbose="yes">
-				<fstab> <rom name="test-noux_fork" /> </fstab>
+			<resource name="RAM" quantum="64M"/>
+			<config verbose="yes" stdin="/null" stdout="/log" stderr="/log">
+				<fstab>
+					<null/> <log/>
+					<rom name="test-noux_fork" />
+				</fstab>
 				<start name="test-noux_fork"> </start>
 			</config>
 		</start>
@@ -46,4 +49,5 @@ build_boot_image {
 
 append qemu_args " -nographic "
 
-run_genode_until "child.*exited with exit value 0.*\n" 20
+run_genode_until "--- parent done ---.*\n" 20
+run_genode_until "child.*exited.*\n" 5 [output_spawn_id]
diff --git a/repos/ports/src/test/noux_fork/test.cc b/repos/ports/src/test/noux_fork/test.cc
index ecebd64474..5d35f07038 100644
--- a/repos/ports/src/test/noux_fork/test.cc
+++ b/repos/ports/src/test/noux_fork/test.cc
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <errno.h>
+#include <sys/wait.h>
 
 enum { MAX_COUNT = 1000 };
 
@@ -22,11 +23,38 @@ int main(int, char **)
 
 	printf("pid %d: fork returned %d\n", getpid(), fork_ret);
 
+	/* child */
 	if (fork_ret == 0) {
 		printf("pid %d: child says hello\n", getpid());
-		for (int j = 0; j < MAX_COUNT; j++) {
-			printf("pid %d: child  j = %d\n", getpid(), j);
+
+		pid_t fork_ret = fork();
+		if (fork_ret < 0) {
+			printf("Error: fork returned %d, errno=%d\n", fork_ret, errno);
+			return -1;
 		}
+
+		printf("pid %d: fork returned %d\n", getpid(), fork_ret);
+
+		/* grand child */
+		if (fork_ret == 0) {
+			printf("pid %d: grand child says hello\n", getpid());
+
+			for (int k = 0; k < MAX_COUNT; k++) {
+				printf("pid %d: grand child k = %d\n", getpid(), k);
+			}
+
+			return 0;
+		};
+
+		for (int j = 0; j < MAX_COUNT; j++) {
+			printf("pid %d: child       j = %d\n", getpid(), j);
+		}
+
+		if (fork_ret != 0) {
+			printf("pid %d: child waits for grand-child exit\n", getpid());
+			waitpid(fork_ret, nullptr, 0);
+		}
+
 		return 0;
 	}
 
@@ -34,9 +62,12 @@ int main(int, char **)
 	       getpid(), fork_ret);
 
 	for (int i = 0; i < MAX_COUNT; ) {
-		printf("pid %d: parent i = %d\n", getpid(), i++);
+		printf("pid %d: parent      i = %d\n", getpid(), i++);
 	}
 
-	pause();
+	printf("pid %d: parent waits for child exit\n", getpid());
+	waitpid(fork_ret, nullptr, 0);
+
+	printf("--- parent done ---\n");
 	return 0;
 }