http: enable keepalive on TCP sockets

diff --git a/connect.c b/connect.c
index 2119c3f74edcd2a976ff0e375c5d8d60d40da2ec..d725b1794f4a6d272a0cc649f57d99453255f8cc 100644 (file)
--- a/connect.c
+++ b/connect.c
@@ -175,6 +175,15 @@ static void get_host_and_port(char **host, const char **port)
        }
 }
 
+static void enable_keepalive(int sockfd)
+{
+       int ka = 1;
+
+       if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
+               fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
+                       strerror(errno));
+}
+
 #ifndef NO_IPV6
 
 static const char *ai_name(const struct addrinfo *ai)
@@ -192,7 +201,8 @@ static const char *ai_name(const struct addrinfo *ai)
  */
 static int git_tcp_connect_sock(char *host, int flags)
 {
-       int sockfd = -1, saved_errno = 0;
+       struct strbuf error_message = STRBUF_INIT;
+       int sockfd = -1;
        const char *port = STR(DEFAULT_GIT_PORT);
        struct addrinfo hints, *ai0, *ai;
        int gai;
@@ -216,21 +226,15 @@ static int git_tcp_connect_sock(char *host, int flags)
        if (flags & CONNECT_VERBOSE)
                fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
 
-       for (ai0 = ai; ai; ai = ai->ai_next) {
+       for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
                sockfd = socket(ai->ai_family,
                                ai->ai_socktype, ai->ai_protocol);
-               if (sockfd < 0) {
-                       saved_errno = errno;
-                       continue;
-               }
-               if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
-                       saved_errno = errno;
-                       fprintf(stderr, "%s[%d: %s]: errno=%s\n",
-                               host,
-                               cnt,
-                               ai_name(ai),
-                               strerror(saved_errno));
-                       close(sockfd);
+               if ((sockfd < 0) ||
+                   (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
+                       strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
+                                   host, cnt, ai_name(ai), strerror(errno));
+                       if (0 <= sockfd)
+                               close(sockfd);
                        sockfd = -1;
                        continue;
                }
@@ -242,11 +246,15 @@ static int git_tcp_connect_sock(char *host, int flags)
        freeaddrinfo(ai0);
 
        if (sockfd < 0)
-               die("unable to connect a socket (%s)", strerror(saved_errno));
+               die("unable to connect to %s:\n%s", host, error_message.buf);
+
+       enable_keepalive(sockfd);
 
        if (flags & CONNECT_VERBOSE)
                fprintf(stderr, "done.\n");
 
+       strbuf_release(&error_message);
+
        return sockfd;
 }
 
@@ -318,6 +326,8 @@ static int git_tcp_connect_sock(char *host, int flags)
        if (sockfd < 0)
                die("unable to connect a socket (%s)", strerror(saved_errno));
 
+       enable_keepalive(sockfd);
+
        if (flags & CONNECT_VERBOSE)
                fprintf(stderr, "done.\n");