Fix: Corrected reported Allow:-header (mostly for 204-responses)

src/client.c

@@ -43,6 +43,7 @@
 #include "reportxml.h"
 #include "refobject.h"
 #include "xslt.h"
+#include "source.h"
 
 #include "client.h"
 #include "auth.h"
@@ -385,6 +386,7 @@ void client_send_101(client_t *client, reuse_t reuse)
 
 void client_send_204(client_t *client)
 {
+    source_t *source;
     ssize_t ret;
 
     if (!client)
@@ -392,10 +394,16 @@ void client_send_204(client_t *client)
 
     client->reuse = ICECAST_REUSE_KEEPALIVE;
 
+    /* We get a source_t* here as this is likely a reply to OPTIONS and we want
+     * to have as much infos as possible in that case.
+     */
+    avl_tree_rlock(global.source_tree);
+    source = source_find_mount_raw(client->uri);
     ret = util_http_build_header(client->refbuf->data, PER_CLIENT_REFBUF_SIZE, 0,
                                  0, 204, NULL,
                                  NULL, NULL,
-                                 NULL, NULL, client);
+                                 NULL, source, client);
+    avl_tree_unlock(global.source_tree);
 
     snprintf(client->refbuf->data + ret, PER_CLIENT_REFBUF_SIZE - ret,
              "Content-Length: 0\r\n\r\n");

src/util.c

@@ -680,6 +680,7 @@ ssize_t util_http_build_header(char * out, size_t len, ssize_t offset,
     char * extra_headers;
     const char *connection_header = "Close";
     const char *upgrade_header = "";
+    const char *allow_header;
 
     if (!out)
         return -1;
@@ -771,14 +772,25 @@ ssize_t util_http_build_header(char * out, size_t len, ssize_t offset,
     else
         currenttime_buffer[0] = '\0';
 
+    if (client) {
+        if (client->admin_command != ADMIN_COMMAND_ERROR) {
+            allow_header = "GET, POST, OPTIONS";
+        } else if (source) {
+            allow_header = "GET, DELETE, OPTIONS";
+        } else {
+            allow_header = "GET, PUT, OPTIONS, SOURCE";
+        }
+    } else {
+        allow_header = "GET, OPTIONS";
+    }
+
     config = config_get_config();
     extra_headers = _build_headers(status, config, source);
     ret = snprintf (out, len, "%sServer: %s\r\nConnection: %s\r\nAccept-Encoding: identity\r\nAllow: %s\r\n%s%s%s%s%s%s%s%s",
                               status_buffer,
                               config->server_id,
                               connection_header,
-                              (client && client->admin_command == ADMIN_COMMAND_ERROR ?
-                                                "GET, SOURCE, OPTIONS" : "GET, OPTIONS"),
+                              allow_header,
                               upgrade_header,
                               currenttime_buffer,
                               contenttype_buffer,