DEV: tcploop: centralize the polling code into wait_for_fd()

There are multiple call places for poll(), let's first centralize them
to make it easier to enhance it. All callers now use the wait_for_fd()
function which was extended to take a timeout and which can return the
indication that an error was seen.

diff --git a/dev/tcploop/tcploop.c b/dev/tcploop/tcploop.c
index 89229f7a648bf7d66c9c284e47f50464b71e87b3..43e171d8694bc09b81e4a48d35cd5f099960513c 100644 (file)
--- a/dev/tcploop/tcploop.c
+++ b/dev/tcploop/tcploop.c
@@ -299,10 +299,10 @@ int addr_to_ss(const char *str, struct sockaddr_storage *ss, struct err_msg *err
        return 0;
 }
 
-/* waits up to one second on fd <fd> for events <events> (POLLIN|POLLOUT).
- * returns poll's status.
+/* waits up to <ms> milliseconds on fd <fd> for events <events> (POLLIN|POLLOUT).
+ * returns poll's status, or -2 if the poller sets POLLERR.
  */
-int wait_on_fd(int fd, int events)
+int wait_on_fd(int fd, int events, int ms)
 {
        struct pollfd pollfd;
        int ret;
@@ -310,9 +310,11 @@ int wait_on_fd(int fd, int events)
        do {
                pollfd.fd = fd;
                pollfd.events = events;
-               ret = poll(&pollfd, 1, 1000);
+               ret = poll(&pollfd, 1, ms);
        } while (ret == -1 && errno == EINTR);
 
+       if (ret == 1 && pollfd.revents & POLLERR)
+               ret = -2;
        return ret;
 }
 
@@ -536,7 +538,7 @@ int tcp_recv(int sock, const char *arg)
                                dolog("recv %d\n", ret);
                                return -1;
                        }
-                       while (!wait_on_fd(sock, POLLIN));
+                       while (!wait_on_fd(sock, POLLIN, 1000));
                        continue;
                }
                dolog("recv %d\n", ret);
@@ -589,7 +591,7 @@ int tcp_send(int sock, const char *arg)
                                dolog("send %d\n", ret);
                                return -1;
                        }
-                       while (!wait_on_fd(sock, POLLOUT));
+                       while (!wait_on_fd(sock, POLLOUT, 1000));
                        continue;
                }
                dolog("send %d\n", ret);
@@ -634,7 +636,7 @@ int tcp_echo(int sock, const char *arg)
                                        dolog("recv %d\n", rcvd);
                                        return -1;
                                }
-                               while (!wait_on_fd(sock, POLLIN));
+                               while (!wait_on_fd(sock, POLLIN, 1000));
                                continue;
                        }
                        dolog("recv %d\n", rcvd);
@@ -651,7 +653,7 @@ int tcp_echo(int sock, const char *arg)
                                        dolog("send %d\n", ret);
                                        return -1;
                                }
-                               while (!wait_on_fd(sock, POLLOUT));
+                               while (!wait_on_fd(sock, POLLOUT, 1000));
                                continue;
                        }
                        dolog("send %d\n", ret);
@@ -676,7 +678,6 @@ int tcp_echo(int sock, const char *arg)
  */
 int tcp_wait(int sock, const char *arg)
 {
-       struct pollfd pollfd;
        int delay = -1; // wait forever
        int ret;
 
@@ -689,14 +690,9 @@ int tcp_wait(int sock, const char *arg)
        }
 
        /* FIXME: this doesn't take into account delivered signals */
-       do {
-               pollfd.fd = sock;
-               pollfd.events = POLLIN | POLLOUT;
-               ret = poll(&pollfd, 1, delay);
-       } while (ret == -1 && errno == EINTR);
-
-       if (ret > 0 && pollfd.revents & POLLERR)
-               return -1;
+       ret = wait_on_fd(sock, POLLIN | POLLOUT, delay);
+       if (ret < 0)
+               return ret;
 
        return 0;
 }
@@ -704,17 +700,11 @@ int tcp_wait(int sock, const char *arg)
 /* waits for the input data to be present */
 int tcp_wait_in(int sock, const char *arg)
 {
-       struct pollfd pollfd;
        int ret;
 
-       do {
-               pollfd.fd = sock;
-               pollfd.events = POLLIN;
-               ret = poll(&pollfd, 1, 1000);
-       } while (ret == -1 && errno == EINTR);
-
-       if (ret > 0 && pollfd.revents & POLLERR)
-               return -1;
+       ret = wait_on_fd(sock, POLLIN, 1000);
+       if (ret < 0)
+               return ret;
 
        return 0;
 }
@@ -722,17 +712,11 @@ int tcp_wait_in(int sock, const char *arg)
 /* waits for the output queue to be empty */
 int tcp_wait_out(int sock, const char *arg)
 {
-       struct pollfd pollfd;
        int ret;
 
-       do {
-               pollfd.fd = sock;
-               pollfd.events = POLLOUT;
-               ret = poll(&pollfd, 1, 1000);
-       } while (ret == -1 && errno == EINTR);
-
-       if (ret > 0 && pollfd.revents & POLLERR)
-               return -1;
+       ret = wait_on_fd(sock, POLLOUT, 1000);
+       if (ret < 0)
+               return ret;
 
        /* Now wait for data to leave the socket */
        do {