unix: don't pass sockaddr to accept()

Shaves a few nanoseconds off the accept() syscall.

src/unix/core.c

@@ -445,14 +445,18 @@ int uv__socket(int domain, int type, int protocol) {
 }
 
 
-int uv__accept(int sockfd, struct sockaddr* saddr, socklen_t slen) {
+int uv__accept(int sockfd) {
   int peerfd;
 
   assert(sockfd >= 0);
 
   while (1) {
 #if __linux__
-    peerfd = uv__accept4(sockfd, saddr, &slen, UV__SOCK_NONBLOCK|UV__SOCK_CLOEXEC);
+    peerfd = uv__accept4(sockfd,
+                         NULL,
+                         NULL,
+                         UV__SOCK_NONBLOCK|UV__SOCK_CLOEXEC);
+
     if (peerfd != -1)
       break;
 
@@ -463,7 +467,9 @@ int uv__accept(int sockfd, struct sockaddr* saddr, socklen_t slen) {
       break;
 #endif
 
-    if ((peerfd = accept(sockfd, saddr, &slen)) == -1) {
+    peerfd = accept(sockfd, NULL, NULL);
+
+    if (peerfd == -1) {
       if (errno == EINTR)
         continue;
       else

src/unix/internal.h

@@ -156,7 +156,7 @@ void uv__stream_init(uv_loop_t* loop, uv_stream_t* stream,
 int uv__stream_open(uv_stream_t*, int fd, int flags);
 void uv__stream_destroy(uv_stream_t* stream);
 void uv__server_io(uv_loop_t* loop, uv__io_t* watcher, int events);
-int uv__accept(int sockfd, struct sockaddr* saddr, socklen_t len);
+int uv__accept(int sockfd);
 int uv__connect(uv_connect_t* req, uv_stream_t* stream, struct sockaddr* addr,
     socklen_t addrlen, uv_connect_cb cb);
 

src/unix/pipe.c

@@ -229,7 +229,6 @@ void uv_pipe_connect(uv_connect_t* req,
 
 /* TODO merge with uv__server_io()? */
 static void uv__pipe_accept(uv_loop_t* loop, uv__io_t* w, int events) {
-  struct sockaddr_un saddr;
   uv_pipe_t* pipe;
   int saved_errno;
   int sockfd;
@@ -239,7 +238,7 @@ static void uv__pipe_accept(uv_loop_t* loop, uv__io_t* w, int events) {
 
   assert(pipe->type == UV_NAMED_PIPE);
 
-  sockfd = uv__accept(pipe->fd, (struct sockaddr *)&saddr, sizeof saddr);
+  sockfd = uv__accept(pipe->fd);
   if (sockfd == -1) {
     if (errno != EAGAIN && errno != EWOULDBLOCK) {
       uv__set_sys_error(pipe->loop, errno);

src/unix/stream.c

@@ -165,7 +165,6 @@ void uv__stream_destroy(uv_stream_t* stream) {
 
 void uv__server_io(uv_loop_t* loop, uv__io_t* w, int events) {
   int fd;
-  struct sockaddr_storage addr;
   uv_stream_t* stream = container_of(w, uv_stream_t, read_watcher);
 
   assert(events == UV__IO_READ);
@@ -181,7 +180,7 @@ void uv__server_io(uv_loop_t* loop, uv__io_t* w, int events) {
    */
   while (stream->fd != -1) {
     assert(stream->accepted_fd < 0);
-    fd = uv__accept(stream->fd, (struct sockaddr*)&addr, sizeof addr);
+    fd = uv__accept(stream->fd);
 
     if (fd < 0) {
       if (errno == EAGAIN || errno == EWOULDBLOCK) {