[Spice-devel] [PATCH v2 3/9] Refactor cursor marshalling for SET, INIT

[Jonathon Jongsma]

Use spice_marshaller_add_by_ref_full() instead of
spice_marshaller_add_by_ref() to allow the marshaller to manage the
lifetime of the referenced data buffer rather than having to manage it
by passing a PipeItem to red_channel_client_init_send_data(). Since the
data is owned by CursorItem (which is not in fact a RedPipeItem, but is
owned by a pipe item and is itself refcounted), we take a reference on
the CursorItem when adding the data buf to the marshaller, and then
unreference it in the marshaller free func.
---
 server/cursor-channel.c | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/server/cursor-channel.c b/server/cursor-channel.c
index 04483af..8befa6e 100644
--- a/server/cursor-channel.c
+++ b/server/cursor-channel.c
@@ -126,13 +126,26 @@ static RedPipeItem *new_cursor_pipe_item(RedChannelClient *rcc, void *data, int
 typedef struct {
     void *data;
     uint32_t size;
+    CursorItem *item;
 } AddBufInfo;
 
-static void add_buf_from_info(SpiceMarshaller *m, AddBufInfo *info)
+static void marshaller_free_cursor_item(uint8_t *data, void *opaque)
+{
+    CursorItem *item = opaque;
+    if (item)
+        cursor_item_unref(item);
+}
+
+static void marshall_cursor_data(SpiceMarshaller *m, AddBufInfo *info)
 {
-    if (info->data) {
-        spice_marshaller_add_by_ref(m, info->data, info->size);
+    spice_return_if_fail(info != NULL);
+    /* the cursor data is owned by 'item', so we need to ensure that 'item'
+     * remains valid until the data is sent. */
+    if (info->item) {
+        cursor_item_ref(info->item);
     }
+    spice_marshaller_add_by_ref_full(m, info->data, info->size,
+                                     marshaller_free_cursor_item, info->item);
 }
 
 static void cursor_fill(CursorChannelClient *ccc, CursorItem *cursor,
@@ -140,6 +153,7 @@ static void cursor_fill(CursorChannelClient *ccc, CursorItem *cursor,
 {
     RedCursorCmd *cursor_cmd;
     addbuf->data = NULL;
+    addbuf->item = cursor;
 
     if (!cursor) {
         red_cursor->flags = SPICE_CURSOR_FLAGS_NONE;
@@ -205,7 +219,7 @@ static void red_marshall_cursor_init(CursorChannelClient *ccc, SpiceMarshaller *
 
     cursor_fill(ccc, cursor_channel->item, &msg.cursor, &info);
     spice_marshall_msg_cursor_init(base_marshaller, &msg);
-    add_buf_from_info(base_marshaller, &info);
+    marshall_cursor_data(base_marshaller, &info);
 }
 
 static void cursor_marshall(CursorChannelClient *ccc,
@@ -215,7 +229,6 @@ static void cursor_marshall(CursorChannelClient *ccc,
     RedChannelClient *rcc = RED_CHANNEL_CLIENT(ccc);
     CursorChannel *cursor_channel = CURSOR_CHANNEL(red_channel_client_get_channel(rcc));
     CursorItem *item = cursor_pipe_item->cursor_item;
-    RedPipeItem *pipe_item = &cursor_pipe_item->base;
     RedCursorCmd *cmd;
 
     spice_return_if_fail(cursor_channel);
@@ -235,13 +248,13 @@ static void cursor_marshall(CursorChannelClient *ccc,
             SpiceMsgCursorSet cursor_set;
             AddBufInfo info;
 
-            red_channel_client_init_send_data(rcc, SPICE_MSG_CURSOR_SET, pipe_item);
+            red_channel_client_init_send_data(rcc, SPICE_MSG_CURSOR_SET, NULL);
             cursor_set.position = cmd->u.set.position;
             cursor_set.visible = cursor_channel->cursor_visible;
 
             cursor_fill(ccc, item, &cursor_set.cursor, &info);
             spice_marshall_msg_cursor_set(m, &cursor_set);
-            add_buf_from_info(m, &info);
+            marshall_cursor_data(m, &info);
             break;
         }
     case QXL_CURSOR_HIDE:
-- 
2.7.4