simple proxy server

src/proxy.c

+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
 #include <stdio.h>
+#include <pthread.h>
+#include "utils/error.h"
+#include "server/server.h"
+#include <sys/poll.h>
+#include <unistd.h>
 
-int main(void)
+void proxy_thread(int client, void *arg)
 {
-	printf("Hello world\n");
+	struct sockaddr_in *addr = arg;
+	char buff[1024];
 
-	return 0;
+	int server;
+	if ((server = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
+		PERROR("socket");
+		return;
+	}
+	if (connect(server, (struct sockaddr *)addr, sizeof(*addr)) < 0) {
+		close(server);
+		PERROR("connect");
+		return;
+	}
+	struct pollfd fds[2] = { { client, POLLIN, 0 }, { server, POLLIN, 0 } };
+
+	while (1) {
+		CHK(poll(fds, 2, -1));
+		ssize_t len;
+		if (fds[0].revents != 0) {
+			if ((len = recv(client, buff, sizeof(buff), 0)) <= 0)
+				break;
+			if (send(server, buff, len, 0) <= 0)
+				break;
+
+			fds[0].revents = 0;
+		}
+		if (fds[1].revents != 0) {
+			if ((len = recv(server, buff, sizeof(buff), 0)) <= 0)
+				break;
+			if (send(client, buff, len, 0) <= 0)
+				break;
+
+			fds[1].revents = 0;
+		}
+	}
+	close(server);
+	close(client);
+	return;
+}
+
+int main(int argc, char *argv[])
+{
+	Server *server;
+	struct sockaddr_in addr;
+
+	if (argc != 4)
+		BLAME("usage: %s <listen-port> <remote-host> <remote-port>",
+		      argv[0]);
+
+	addr.sin_family = AF_INET;
+	addr.sin_port = htons(atoi(argv[3]));
+	if (!inet_aton(argv[2], &addr.sin_addr))
+		BLAME("invalid remote host: %s", argv[2]);
+
+	CHKN(server = server_new(atoi(argv[1])));
+
+	CHK(server_start(server, proxy_thread, &addr));
+
+	CHK(server_join(server));
+
+	return EXIT_SUCCESS;
 }