rspreload: Make socket_fallback() call more generic

socket_fallback is used to switch from an rsocket to a normal
socket in the case of failures.  Rename the call and make it
more generic, so that it can switch between an rsocket and
a normal socket in either direction.  This will be used to
support fork().

Signed-off-by: Sean Hefty <sean.hefty@intel.com>

diff --git a/src/preload.c b/src/preload.c
index 2750b301b60daf1c7b35ae60be2007b0cc346318..cc0d7eba27e0983b407d765f685e3299b0b2bcec 100644 (file)
--- a/src/preload.c
+++ b/src/preload.c
@@ -252,51 +252,63 @@ out:
 }
 
 /*
- * Convert from an rsocket to a normal socket.  The new socket should have the
- * same settings and bindings as the rsocket.  We currently only handle setting
- * a few of the more common values.
+ * Convert between an rsocket and a normal socket.  The new socket should have the
+ * same settings and bindings as the current socket.  We currently only handle
+ * setting a few of the more common values.
  */
-static int socket_fallback(int socket, int *fd)
+static int
+transpose_socket(int index, int *fd, enum fd_type new_type,
+       int (*socket_new)(int domain, int type, int protocol),
+       int (*close_old)(int socket),
+       int (*close_new)(int socket),
+       int (*getsockname_old)(int socket, struct sockaddr *addr,
+                              socklen_t *addrlen),
+       int (*getsockopt_old)(int socket, int level, int optname,
+                             void *optval, socklen_t *optlen),
+       int (*setsockopt_new)(int socket, int level, int optname,
+                             const void *optval, socklen_t optlen),
+       int (*fcntl_old)(int socket, int cmd, ... /* arg */),
+       int (*fcntl_new)(int socket, int cmd, ... /* arg */))
 {
        socklen_t len = 0;
        int new_fd, param, ret;
 
-       ret = rgetsockname(*fd, NULL, &len);
+       ret = getsockname_old(*fd, NULL, &len);
        if (ret)
                return ret;
 
        param = (len == sizeof(struct sockaddr_in6)) ? PF_INET6 : PF_INET;
-       new_fd = real_socket(param, SOCK_STREAM, IPPROTO_TCP);
+       new_fd = socket_new(param, SOCK_STREAM, 0);
        if (new_fd < 0)
                return new_fd;
 
-       ret = rfcntl(*fd, F_GETFL);
+       ret = fcntl_old(*fd, F_GETFL);
        if (ret > 0)
-               ret = real_fcntl(new_fd, F_SETFL, ret);
+               ret = fcntl_new(new_fd, F_SETFL, ret);
        if (ret)
                goto err;
 
        len = sizeof param;
-       ret = rgetsockopt(*fd, SOL_SOCKET, SO_REUSEADDR, &param, &len);
+       ret = getsockopt_old(*fd, SOL_SOCKET, SO_REUSEADDR, &param, &len);
        if (param && !ret)
-               ret = real_setsockopt(new_fd, SOL_SOCKET, SO_REUSEADDR, &param, len);
+               ret = setsockopt_new(new_fd, SOL_SOCKET, SO_REUSEADDR, &param, len);
        if (ret)
                goto err;
 
        len = sizeof param;
-       ret = rgetsockopt(*fd, IPPROTO_TCP, TCP_NODELAY, &param, &len);
+       ret = getsockopt_old(*fd, IPPROTO_TCP, TCP_NODELAY, &param, &len);
        if (param && !ret)
-               ret = real_setsockopt(new_fd, IPPROTO_TCP, TCP_NODELAY, &param, len);
+               ret = setsockopt_new(new_fd, IPPROTO_TCP, TCP_NODELAY, &param, len);
        if (ret)
                goto err;
 
-       rclose(*fd);
-       fd_store(socket, new_fd, fd_normal);
+       close_old(*fd);
+       fd_store(socket, new_fd, new_type);
        *fd = new_fd;
        return 0;
 
 err:
-       real_close(new_fd);
+       close_new(new_fd);
        return ret;
 }
 
@@ -351,7 +363,10 @@ int bind(int socket, const struct sockaddr *addr, socklen_t addrlen)
                if (!sin->sin_port || ntohs(sin->sin_port) > 1024)
                        return rbind(fd, addr, addrlen);
 
-               ret = socket_fallback(socket, &fd);
+               ret = transpose_socket(socket, &fd, fd_normal, real_socket,
+                                      rclose, real_close, rgetsockname,
+                                      rgetsockopt, real_setsockopt,
+                                      rfcntl, real_fcntl);
                if (ret)
                        return ret;
        }
@@ -401,7 +416,10 @@ int connect(int socket, const struct sockaddr *addr, socklen_t addrlen)
                                return ret;
                }
 
-               ret = socket_fallback(socket, &fd);
+               ret = transpose_socket(socket, &fd, fd_normal, real_socket,
+                                      rclose, real_close, rgetsockname,
+                                      rgetsockopt, real_setsockopt,
+                                      rfcntl, real_fcntl);
                if (ret)
                        return ret;
        }