network: uniform ff_listen_bind and ff_listen_connect

Document the functions and have both use a millisecond timeout and
check for interrupt.

libavformat/network.c

@@ -189,8 +189,29 @@ int ff_is_multicast_address(struct sockaddr *addr)
     return 0;
 }
 
+static int ff_poll_interrupt(struct pollfd *p, nfds_t nfds, int timeout,
+                             AVIOInterruptCB *cb)
+{
+    int runs = timeout / POLLING_TIME;
+    int ret = 0;
+
+    do {
+        if (ff_check_interrupt(cb))
+            return AVERROR_EXIT;
+        ret = poll(p, nfds, POLLING_TIME);
+        if (ret != 0)
+            break;
+    } while (timeout < 0 || runs-- > 0);
+
+    if (!ret)
+        return AVERROR(ETIMEDOUT);
+    if (ret < 0)
+        return AVERROR(errno);
+    return ret;
+}
+
 int ff_listen_bind(int fd, const struct sockaddr *addr,
-                   socklen_t addrlen, int timeout)
+                   socklen_t addrlen, int timeout, URLContext *h)
 {
     int ret;
     int reuse = 1;
@@ -204,9 +225,9 @@ int ff_listen_bind(int fd, const struct sockaddr *addr,
     if (ret)
         return ff_neterrno();
 
-    ret = poll(&lp, 1, timeout >= 0 ? timeout : -1);
-    if (ret <= 0)
-        return AVERROR(ETIMEDOUT);
+    ret = ff_poll_interrupt(&lp, 1, timeout, &h->interrupt_callback);
+    if (ret < 0)
+        return ret;
 
     ret = accept(fd, NULL, NULL);
     if (ret < 0)
@@ -236,15 +257,9 @@ int ff_listen_connect(int fd, const struct sockaddr *addr,
             continue;
         case AVERROR(EINPROGRESS):
         case AVERROR(EAGAIN):
-            while (timeout--) {
-                if (ff_check_interrupt(&h->interrupt_callback))
-                    return AVERROR_EXIT;
-                ret = poll(&p, 1, 100);
-                if (ret > 0)
-                    break;
-            }
-            if (ret <= 0)
-                return AVERROR(ETIMEDOUT);
+            ret = ff_poll_interrupt(&p, 1, timeout, &h->interrupt_callback);
+            if (ret < 0)
+                return ret;
             optlen = sizeof(ret);
             if (getsockopt (fd, SOL_SOCKET, SO_ERROR, &ret, &optlen))
                 ret = AVUNERROR(ff_neterrno());

libavformat/network.h

@@ -210,9 +210,38 @@ const char *ff_gai_strerror(int ecode);
 
 int ff_is_multicast_address(struct sockaddr *addr);
 
+#define POLLING_TIME 100 /// Time in milliseconds between interrupt check
+
+/**
+ * Bind to a file descriptor and poll for a connection.
+ *
+ * @param fd      First argument of bind().
+ * @param addr    Second argument of bind().
+ * @param addrlen Third argument of bind().
+ * @param timeout Polling timeout in milliseconds.
+ * @param h       URLContext providing interrupt check
+ *                callback and logging context.
+ * @return        A non-blocking file descriptor on success
+ *                or an AVERROR on failure.
+ */
 int ff_listen_bind(int fd, const struct sockaddr *addr,
-                   socklen_t addrlen, int timeout);
+                   socklen_t addrlen, int timeout,
+                   URLContext *h);
+
+/**
+ * Connect to a file descriptor and poll for result.
+ *
+ * @param fd       First argument of connect(),
+ *                 will be set as non-blocking.
+ * @param addr     Second argument of connect().
+ * @param addrlen  Third argument of connect().
+ * @param timeout  Polling timeout in milliseconds.
+ * @param h        URLContext providing interrupt check
+ *                 callback and logging context.
+ * @return         0 on success, AVERROR on failure.
+ */
 int ff_listen_connect(int fd, const struct sockaddr *addr,
                       socklen_t addrlen, int timeout,
                       URLContext *h);
+
 #endif /* AVFORMAT_NETWORK_H */

libavformat/tcp.c

@@ -92,13 +92,13 @@ static int tcp_open(URLContext *h, const char *uri, int flags)
 
     if (listen_socket) {
         if ((fd = ff_listen_bind(fd, cur_ai->ai_addr, cur_ai->ai_addrlen,
-                                 listen_timeout)) < 0) {
+                                 listen_timeout, h)) < 0) {
             ret = fd;
             goto fail1;
         }
     } else {
         if ((ret = ff_listen_connect(fd, cur_ai->ai_addr, cur_ai->ai_addrlen,
-                                     timeout, h)) < 0) {
+                                     timeout * 100, h)) < 0) {
 
             if (ret == AVERROR_EXIT)
                 goto fail1;