1 files changed, 179 insertions, 0 deletions
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..466ab83
--- /dev/null
+++ b/main.c
@@ -0,0 +1,179 @@
+#define _POSIX_C_SOURCE 200112L
+
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include <errno.h>
+#include <limits.h>
+#include <netdb.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "log.h"
+
+#ifndef OPEN_MAX
+#define OPEN_MAX 1024
+#endif
+
+#define PORT "3000"
+#define BUFSIZE 1024
+
+static int
+create_server(const char *port)
+{
+	int fd, yes = 1;
+	struct addrinfo *res, *p, hints;
+
+	memset(&hints, 0, sizeof hints);
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_PASSIVE;
+
+	if (getaddrinfo(NULL, port, &hints, &res) != 0) {
+		perror("getaddrinfo");
+		return -1;
+	}
+	for (p = res; p != NULL; p = p->ai_next) {
+		if ((fd = socket(p->ai_family, p->ai_socktype, p->ai_protocol))
+		    == -1) {
+			perror("socket");
+			continue;
+		}
+		if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes,
+			       sizeof(int)) == -1) {
+			perror("setsockopt");
+			close(fd);
+			return -1;
+		}
+		if (ioctl(fd, FIONBIO, &yes) == -1) {
+			perror("ioctl");
+			close(fd);
+			return -1;
+		}
+		if (bind(fd, p->ai_addr, p->ai_addrlen) == -1) {
+			perror("bind");
+			continue;
+		}
+		break;
+	}
+
+	freeaddrinfo(res);
+
+	if (p == NULL) {
+		fprintf(stderr, "failed to bind\n");
+		return -1;
+	}
+	if (listen(fd, 32) == -1) {
+		perror("listen");
+		return -1;
+	}
+	logmsg(LOG_INFO, "listening on %s", port);
+	return fd;
+}
+
+static int
+accept_connection(int s_fd)
+{
+	int c_fd;
+
+	if ((c_fd = accept(s_fd, NULL, NULL)) == -1) {
+		if (errno != EWOULDBLOCK || errno != EAGAIN) {
+			perror("accept");
+			exit(1);
+		}
+		return -1;
+	}
+	logmsg(LOG_INFO, "connection accepted");
+
+	return c_fd;
+}
+
+static void
+handle_client(int c_fd)
+{
+	int n;
+	char buf[BUFSIZE];
+
+	n = recv(c_fd, &buf, BUFSIZE - 1, 0);
+	switch (n) {
+	case -1:
+		if (errno != EWOULDBLOCK || errno != EAGAIN) {
+			perror("recv");
+		}
+	case 0:
+		logmsg(LOG_INFO, "connection closed by client");
+	default:
+		buf[n] = '\0';
+		if (send(c_fd, buf, n, 0) == -1) {
+			perror("send");
+		}
+	}
+	close(c_fd);
+}
+
+static void
+main_loop(int s_fd)
+{
+	int i, rc, end_server = 0;
+	int c_fd, nfds = 1, curr_size = 0;
+	struct pollfd pfds[OPEN_MAX];
+
+	memset(pfds, 0, sizeof(pfds));
+	pfds[0].fd = s_fd;
+	pfds[0].events = POLLIN;
+
+	do {
+		rc = poll(pfds, nfds, -1);
+		if (rc == -1) {
+			perror("poll");
+			break;
+		}
+		if (rc == 0) {
+			fprintf(stderr, "poll timeout\n");
+			break;
+		}
+		curr_size = nfds;
+		for (i = 0; i < curr_size; i++) {
+			if (pfds[i].revents == 0)
+				continue;
+
+			if (pfds[i].revents != POLLIN) {
+				logmsg(LOG_INFO, "revents not POLLIN\n");
+				end_server = 1;
+				break;
+			}
+			if (pfds[i].fd == s_fd) {
+				do {
+					c_fd = accept_connection(s_fd);
+					if (c_fd != -1) {
+						pfds[nfds].fd = c_fd;
+						pfds[nfds].events = POLLIN;
+						nfds++;
+					}
+				} while (c_fd != -1);
+			} else {
+				handle_client(pfds[i].fd);
+				pfds[i].fd = -1;
+			}
+		}
+	} while (end_server == 0);
+}
+
+int
+main()
+{
+	int s_fd;
+
+	s_fd = create_server(PORT);
+	if (s_fd == -1) {
+		fprintf(stderr, "failed to create server\n");
+		exit(0);
+	}
+	main_loop(s_fd);
+
+	return 0;
+}