Initial import

usock.c

@@ -0,0 +1,102 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <netdb.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+
+#include "usock.h"
+
+int usock(int type, const char *host, const char *service) {
+	int sock = -1;
+
+	if (service && !(type & USOCK_UNIX)) {
+		struct addrinfo *result, *rp;
+
+		struct addrinfo hints = {
+			.ai_family = (type & USOCK_IPV6ONLY) ? AF_INET6 :
+				(type & USOCK_IPV4ONLY) ? AF_INET : AF_UNSPEC,
+			.ai_socktype = ((type & 0xff) == USOCK_TCP)
+				? SOCK_STREAM : SOCK_DGRAM,
+			.ai_flags = AI_ADDRCONFIG
+				| ((type & USOCK_SERVER) ? AI_PASSIVE : 0)
+				| ((type & USOCK_NUMERIC) ? AI_NUMERICHOST : 0),
+		};
+
+		if (getaddrinfo(host, service, &hints, &result)) {
+			return -1;
+		}
+
+		for (rp = result; rp != NULL; rp = rp->ai_next) {
+			if ((sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol))
+			== -1) {
+				continue;
+			}
+
+			if (!(type & USOCK_NOCLOEXEC)) {
+				fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC);
+			}
+
+			if (type & USOCK_NONBLOCK) {
+				fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_NONBLOCK);
+			}
+
+			if (type & USOCK_SERVER) {
+				const int one = 1;
+				setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+
+				if (!bind(sock, rp->ai_addr, rp->ai_addrlen)
+				&& ((type & 0xff) != USOCK_TCP || !listen(sock, SOMAXCONN))) {
+					break;
+				}
+			} else {
+				if (!connect(sock, rp->ai_addr, rp->ai_addrlen)
+				|| errno == EINPROGRESS) {
+					break;
+				}
+			}
+
+			close(sock);
+			sock = -1;
+		}
+		freeaddrinfo(result);
+	} else {
+		struct sockaddr_un sun = {.sun_family = AF_UNIX};
+		if (strlen(host) >= sizeof(sun.sun_path)) {
+			errno = EINVAL;
+			return -1;
+		}
+		strcpy(sun.sun_path, host);
+
+		if ((sock = socket(AF_UNIX, ((type & 0xff) == USOCK_TCP)
+				? SOCK_STREAM : SOCK_DGRAM, 0)) == -1) {
+			return -1;
+		}
+
+		if (!(type & USOCK_NOCLOEXEC)) {
+			fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC);
+		}
+
+		if (type & USOCK_NONBLOCK) {
+			fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_NONBLOCK);
+		}
+
+		if (type & USOCK_SERVER) {
+			if (bind(sock, (struct sockaddr*)&sun, sizeof(sun)) ||
+			((type & 0xff) == USOCK_TCP && listen(sock, SOMAXCONN))) {
+				close(sock);
+				return -1;
+			}
+		} else {
+			if (connect(sock, (struct sockaddr*)&sun, sizeof(sun))
+			&& errno != EINPROGRESS) {
+				close(sock);
+				return -1;
+			}
+		}
+	}
+	return sock;
+}