serve: Refactor some socket utility code into its own module.

We'll be using this in proxy mode later
2013-02-13 13:43:52 +00:00
parent 0fcbe04f80
commit ac560bd907
5 changed files with 158 additions and 101 deletions
--- a/src/sockutil.c
+++ b/src/sockutil.c
@@ -0,0 +1,104 @@
+#include "sockutil.h"
+#include "util.h"
+
+size_t sockaddr_size(const struct sockaddr* sa)
+{
+	size_t ret = 0;
+
+	switch( sa->sa_family ) {
+		case AF_INET:
+			ret = sizeof( struct sockaddr_in );
+			break;
+		case AF_INET6:
+			ret = sizeof( struct sockaddr_in6 );
+			break;
+	}
+
+	return ret;
+}
+
+const char* sockaddr_address_string(const struct sockaddr* sa, char* dest, size_t len)
+{
+	NULLCHECK( sa );
+	NULLCHECK( dest );
+
+	struct sockaddr_in*  in  = ( struct sockaddr_in*  ) sa;
+	struct sockaddr_in6* in6 = ( struct sockaddr_in6* ) sa;
+
+	unsigned short real_port = ntohs( in->sin_port ); // common to in and in6
+	size_t size;
+	const char* ret = NULL;
+
+	memset( dest, 0, len );
+
+	if ( sa->sa_family == AF_INET ) {
+		ret = inet_ntop( AF_INET, &in->sin_addr, dest, len );
+	} else if ( sa->sa_family == AF_INET6 ) {
+		ret = inet_ntop( AF_INET6, &in6->sin6_addr, dest, len );
+	} else {
+		strncpy( dest, "???", len );
+	}
+
+	if ( NULL != ret && real_port > 0 ) {
+		size = strlen( dest );
+		snprintf( dest + size, len - size, " port %d", real_port );
+	}
+
+	return ret;
+}
+
+int sock_set_reuseaddr(int fd, int optval)
+{
+	return setsockopt( fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval) );
+}
+
+/* Set the tcp_nodelay option */
+int sock_set_tcp_nodelay(int fd, int optval)
+{
+	return setsockopt( fd, IPPROTO_TCP, TCP_NODELAY, &optval, sizeof(optval) );
+}
+
+int sock_try_bind(int fd, const struct sockaddr* sa)
+{
+	int bind_result;
+	char s_address[256];
+
+	sockaddr_address_string( sa, &s_address[0], 256 );
+
+	do {
+		bind_result = bind( fd, sa, sockaddr_size( sa ) );
+		if ( 0 == bind_result ) {
+			info( "Bound to %s", s_address );
+			break;
+		}
+		else {
+			warn( SHOW_ERRNO( "Couldn't bind to %s", s_address ) );
+
+			switch ( errno ) {
+				/* bind() can give us EACCES, EADDRINUSE, EADDRNOTAVAIL, EBADF,
+				 * EINVAL, ENOTSOCK, EFAULT, ELOOP, ENAMETOOLONG, ENOENT,
+				 * ENOMEM, ENOTDIR, EROFS
+				 *
+				 * Any of these other than  EADDRINUSE & EADDRNOTAVAIL signify
+				 * that there's a logic error somewhere.
+				 *
+				 * EADDRINUSE is fatal: if there's something already where we
+				 * want to be listening, we have no guarantees that any clients
+				 * will cope with it.
+				 */
+				case EADDRNOTAVAIL:
+					debug( "retrying" );
+					sleep( 1 );
+					continue;
+				case EADDRINUSE:
+					warn( "%s in use, giving up.", s_address );
+					break;
+				default:
+					warn( "giving up" );
+			}
+		}
+	} while ( 1 );
+
+	return bind_result;
+}
+