Fix build on FreeBSD

Still don't know if it works; there are lots of warnings when building
with Clang, so gotta look at that later.  But it's good to have a
FreeBSD buildbot worker I can SSH into again!

src/lib/lwan-io-wrappers.c

@@ -270,13 +270,13 @@ int lwan_sendfile_fd(struct lwan_request *request,
     }
 }
 #elif defined(__FreeBSD__) || defined(__APPLE__)
-int lwan_sendfile(struct lwan_request *request,
-                  int out_fd,
-                  int in_fd,
-                  off_t offset,
-                  size_t count,
-                  const char *header,
-                  size_t header_len)
+int lwan_sendfile_fd(struct lwan_request *request,
+                     int out_fd,
+                     int in_fd,
+                     off_t offset,
+                     size_t count,
+                     const char *header,
+                     size_t header_len)
 {
     struct sf_hdtr headers = {.headers =
                                   (struct iovec[]){{.iov_base = (void *)header,

src/lib/lwan-io-wrappers.h

@@ -21,6 +21,7 @@
 #pragma once
 
 #include <errno.h>
+#include <sys/socket.h>
 #include <sys/uio.h>
 #include <unistd.h>
 

src/lib/lwan-socket.c

@@ -245,15 +245,14 @@ static int set_socket_options(const struct lwan *l, int fd)
     SET_SOCKET_OPTION(SOL_SOCKET, SO_LINGER,
                       (&(struct linger){.l_onoff = 1, .l_linger = 1}));
 
-    SET_SOCKET_OPTION_MAY_FAIL(SOL_TCP, TCP_NODELAY, (int[]){1});
-
 #ifdef __linux__
 
 #ifndef TCP_FASTOPEN
 #define TCP_FASTOPEN 23
 #endif
 
     SET_SOCKET_OPTION_MAY_FAIL(SOL_SOCKET, SO_REUSEADDR, (int[]){1});
+    SET_SOCKET_OPTION_MAY_FAIL(SOL_TCP, TCP_NODELAY, (int[]){1});
     SET_SOCKET_OPTION_MAY_FAIL(SOL_TCP, TCP_FASTOPEN, (int[]){5});
     SET_SOCKET_OPTION_MAY_FAIL(SOL_TCP, TCP_QUICKACK, (int[]){0});
     SET_SOCKET_OPTION_MAY_FAIL(SOL_TCP, TCP_DEFER_ACCEPT,

src/lib/missing/sys/socket.h

@@ -27,6 +27,10 @@
 #define MSG_MORE 0
 #endif
 
+#ifndef MSG_NOSIGNAL
+#define MSG_NOSIGNAL 0
+#endif
+
 #ifndef SOCK_CLOEXEC
 #define SOCK_CLOEXEC 0
 #endif