[ptest-runner][PATCH 2/4] Recreate pipe for each test

[Joshua Watt <jpewhacker@gmail.com>]

The write end of the pipe has to be closed by ptest-runner to make sure
that it will get EOF when the child process is done with it. This means
that a new pipe needs to be opened for each child so that the write ends
can be passed to it.

Fixes the problem where tests would be reported with no output when
ptest-runner was told to run multiple tests because they were passed
invalid stdin/stderr pipes.

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
---
 utils.c | 45 ++++++++++++++++++++++++---------------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/utils.c b/utils.c
index 6a6e848..c1188dd 100644
--- a/utils.c
+++ b/utils.c
@@ -61,7 +61,6 @@ static struct {
 
 	unsigned int timeout;
 	int timeouted;
-	pid_t pid;
 	int padding1;
 } _child_reader;
 
@@ -414,8 +413,8 @@ run_ptests(struct ptest_list *head, const struct ptest_options opts,
 	char stime[GET_STIME_BUF_SIZE];
 
 	pid_t child;
-	int pipefd_stdout[2];
-	int pipefd_stderr[2];
+	int pipefd_stdout[2] = {-1, -1};
+	int pipefd_stderr[2] = {-1, -1};
 	time_t sttime, entime;
 	time_t duration;
 	int slave;
@@ -429,28 +428,22 @@ run_ptests(struct ptest_list *head, const struct ptest_options opts,
 
 	do
 	{
-		if ((rc = pipe2(pipefd_stdout, 0)) == -1)
-			break;
-
-		if ((rc = pipe2(pipefd_stderr, 0)) == -1) {
-			close(pipefd_stdout[0]);
-			close(pipefd_stdout[1]);
-			break;
-		}
-
 		if (isatty(0) && ioctl(0, TIOCNOTTY) == -1) {
 			fprintf(fp, "ERROR: Unable to detach from controlling tty, %s\n", strerror(errno));
 		}
 
-		_child_reader.fds[0] = pipefd_stdout[0];
-		_child_reader.fds[1] = pipefd_stderr[0];
-		_child_reader.fps[0] = fp;
-		_child_reader.fps[1] = fp_stderr;
-		_child_reader.timeout = opts.timeout;
-		_child_reader.timeouted = 0;
 
 		fprintf(fp, "START: %s\n", progname);
 		PTEST_LIST_ITERATE_START(head, p)
+			if ((rc = pipe2(pipefd_stdout, 0)) == -1)
+				break;
+
+			if ((rc = pipe2(pipefd_stderr, 0)) == -1) {
+				close(pipefd_stdout[0]);
+				close(pipefd_stdout[1]);
+				break;
+			}
+
 			char *ptest_dir = strdup(p->run_ptest);
 			if (ptest_dir == NULL) {
 				rc = -1;
@@ -497,7 +490,12 @@ run_ptests(struct ptest_list *head, const struct ptest_options opts,
 				do_close(&pipefd_stdout[1]);
 				do_close(&pipefd_stderr[1]);
 
-				_child_reader.pid = child;
+				_child_reader.fds[0] = pipefd_stdout[0];
+				_child_reader.fds[1] = pipefd_stderr[0];
+				_child_reader.fps[0] = fp;
+				_child_reader.fps[1] = fp_stderr;
+				_child_reader.timeout = opts.timeout;
+				_child_reader.timeouted = 0;
 				if (setpgid(child, pgid) == -1) {
 					fprintf(fp, "ERROR: setpgid() failed, %s\n", strerror(errno));
 				}
@@ -543,7 +541,7 @@ run_ptests(struct ptest_list *head, const struct ptest_options opts,
 						 * the pipes until EOF to make
 						 * sure we get all the output
 						 */
-						kill(-_child_reader.pid, SIGKILL);
+						kill(-child, SIGKILL);
 						_child_reader.timeouted = 1;
 					}
 
@@ -585,7 +583,7 @@ run_ptests(struct ptest_list *head, const struct ptest_options opts,
 				 * dead
 				 */
 				if (!_child_reader.timeouted) {
-					kill(-_child_reader.pid, SIGKILL);
+					kill(-child, SIGKILL);
 				}
 				status = wait_child(child);
 
@@ -607,6 +605,11 @@ run_ptests(struct ptest_list *head, const struct ptest_options opts,
 				fprintf(fp, "%s\n", get_stime(stime, GET_STIME_BUF_SIZE, entime));
 			}
 			free(ptest_dir);
+			do_close(&pipefd_stdout[0]);
+			do_close(&pipefd_stdout[1]);
+			do_close(&pipefd_stderr[0]);
+			do_close(&pipefd_stderr[1]);
+
 		PTEST_LIST_ITERATE_END
 		fprintf(fp, "STOP: %s\n", progname);
 
-- 
2.33.0