[LTP] [PATCH] setrlimit testcase fix

[Harsh P. B. <ha...@li...>]

Current testcase for setrlimit for parameter RLIMIT_FSIZE
does not convey the number of bytes actually written from
child process to parent, as the child process writes to its
own copy of global variable. This patch introduces a pipe
to send the information from child to the parent process.

Signed-off-by: Harsh Prateek Bora <ha...@li...>
---
 testcases/kernel/syscalls/setrlimit/setrlimit01.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/testcases/kernel/syscalls/setrlimit/setrlimit01.c b/testcases/kernel/syscalls/setrlimit/setrlimit01.c
index 6952eb3..d8949c6 100644
--- a/testcases/kernel/syscalls/setrlimit/setrlimit01.c
+++ b/testcases/kernel/syscalls/setrlimit/setrlimit01.c
@@ -156,7 +156,12 @@ void test2()
 	 * an wired value!  So, it is essential to fflush the parent's
 	 * write buffer HERE
 	 */
+	int pipefd[2];
 	fflush(stdout);
+	if (pipe(pipefd) == -1) {
+		perror("pipe");
+		exit(EXIT_FAILURE);
+	}
 
 	/*
 	 * Spawn a child process, and reduce the filesize to
@@ -170,6 +175,7 @@ void test2()
 	}
 
 	if (pid == 0) {
+		close(pipefd[0]); /* close unused read end */
 		rlim.rlim_cur = 10;
 		rlim.rlim_max = 10;
 		if ((setrlimit(RLIMIT_FSIZE, &rlim)) == -1) {
@@ -181,6 +187,8 @@ void test2()
 		}
 
 		if ((bytes = write(fd, buf, 26)) != 10) {
+			write(pipefd[1], &bytes, sizeof(bytes));
+			close(pipefd[1]); /* EOF */
 			exit(3);
 		}
 		exit(0);	/* success */
@@ -202,6 +210,9 @@ void test2()
 		tst_resm(TFAIL, "creating testfile failed");
 		break;
 	case 3:
+		close(pipefd[1]); /* close unused write end */
+		read(pipefd[0], &bytes, sizeof(bytes));
+		close(pipefd[0]);
 		tst_resm(TFAIL, "setrlimit failed, expected "
 			 "10 got %d", bytes);
 		break;
-- 
1.7.1.1