Add a test implementation of bidirectional pipe between to programs

1 files changed, 74 insertions, 0 deletions

diff --git a/bidirtest.c b/bidirtest.c
new file mode 100644
index 0000000..995b222
--- /dev/null
+++ b/bidirtest.c
@@ -0,0 +1,74 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <wait.h>
+#include <string.h>
+
+volatile sig_atomic_t sig = 0;
+
+char *cmd1[] = {"nc", "-l", "12345", NULL};
+char *cmd2[] = {"nc", "-l", "12346", NULL};
+
+void
+handle_sig(int _sig, siginfo_t *siginfo, void *ucontext)
+{
+	sig = _sig;
+}
+
+int
+main(int argc, char **argv)
+{
+	int p1[2], p2[2];
+	pid_t pid1, pid2;
+
+	struct sigaction act;
+	memset(&act, 0, sizeof(act));
+
+	act.sa_sigaction = &handle_sig;
+	act.sa_flags = SA_SIGINFO;
+
+	sigaction(SIGINT, &act, NULL);
+	sigaction(SIGTERM, &act, NULL);
+	sigaction(SIGHUP, &act, NULL);
+
+	pipe(p1);
+	pipe(p2);
+
+	switch ((pid1 = fork())) {
+	case 0:
+		close(0);
+		close(1);
+		dup2(p1[0], 0);
+		dup2(p2[1], 1);
+
+		execvp(cmd1[0], cmd1);
+		break;
+	default:
+		break;
+	}
+
+	switch ((pid2 = fork())) {
+	case 0:
+		close(0);
+		close(1);
+		dup2(p2[0], 0);
+		dup2(p1[1], 1);
+
+		execvp(cmd2[0], cmd2);
+		break;
+	default:
+		break;
+	}
+
+	while (wait(NULL) != -1 || errno == EINTR) {
+		if (sig != 0) {
+			kill(pid1, sig);
+			kill(pid2, sig);
+
+			sig = 0;
+		}
+	}
+
+	return 0;
+}