[rhythmbox] podcast: restart downloads from the start on HTTP 416 errors

[Jonathan Matthew <jmatthew src gnome org>]

commit 24ce14f509edfb2fa6c969626153b8be8fce5c24
Author: Jonathan Matthew <jonathan d14n org>
Date:   Wed Dec 23 08:37:23 2020 +1000

    podcast: restart downloads from the start on HTTP 416 errors
    
    If we get a Requested Range Not Satisfiable response, we can't
    resume a partial download, so we have to retry from the start.
    Some podcast hosts do this despite advertising support for range
    requests.

 podcast/rb-podcast-manager.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)
---
diff --git a/podcast/rb-podcast-manager.c b/podcast/rb-podcast-manager.c
index 5b689b38b..76c2e0508 100644
--- a/podcast/rb-podcast-manager.c
+++ b/podcast/rb-podcast-manager.c
@@ -1970,6 +1970,7 @@ download_task (GTask *task, gpointer source_object, gpointer task_data, GCancell
        gboolean retry;
        gboolean eof;
        goffset start, end, total;
+       gboolean range_request;
        int retries;
        GValue val = {0,};
        char *dl_uri;
@@ -1982,6 +1983,7 @@ download_task (GTask *task, gpointer source_object, gpointer task_data, GCancell
         */
        retries = 5;
        remote_size = 0;
+       range_request = TRUE;
        while (retries-- > 0) {
                if (download->in_stream != NULL) {
                        g_input_stream_close (download->in_stream, NULL, NULL);
@@ -2113,6 +2115,12 @@ download_task (GTask *task, gpointer source_object, gpointer task_data, GCancell
                        soup_message_headers_set_range (download->request->request_headers, downloaded, -1);
                download->in_stream = soup_session_send (pd->priv->soup_session, download->request, 
download->cancel, &error);
                if (error == NULL && !SOUP_STATUS_IS_SUCCESSFUL (download->request->status_code)) {
+                       if (download->request->status_code == SOUP_STATUS_REQUESTED_RANGE_NOT_SATISFIABLE) {
+                               rb_debug ("got requested range not satisfiable, disabling resume and 
retrying");
+                               range_request = FALSE;
+                               downloaded = 0;
+                               continue;
+                       }
                        error = g_error_new (SOUP_HTTP_ERROR, download->request->status_code, "%s", 
download->request->reason_phrase);
                }
 
@@ -2139,6 +2147,7 @@ download_task (GTask *task, gpointer source_object, gpointer task_data, GCancell
                                remote_size = total;
                                rb_debug ("resuming download at offset %ld, %ld bytes left", start, total);
                        } else {
+                               range_request = FALSE;
                                downloaded = 0;
                                remote_size = soup_message_headers_get_content_length 
(download->request->response_headers);
                                rb_debug ("server didn't honour range request, starting again, total %ld", 
remote_size);
@@ -2215,7 +2224,11 @@ download_task (GTask *task, gpointer source_object, gpointer task_data, GCancell
                                rb_debug ("full file downloaded");
                                break;
                        }
-                       rb_debug ("haven't got the whole file yet, retrying");
+                       if (range_request == FALSE) {
+                               rb_debug ("range request not supported, restarting");
+                               downloaded = 0;
+                       } else
+                               rb_debug ("haven't got the whole file yet, retrying at %ld", downloaded);
                } else if (retry == FALSE) {
                        rb_debug ("not retrying");
                        break;