[html5] r2907 - [gow] (2) Fix race conditions in the <video> load mechanism.

whatwg at whatwg.org whatwg at whatwg.org
Wed Mar 25 01:40:04 PDT 2009
Previous message: [html5] r2906 - [e] (0) v2 note
Next message: [html5] r2908 - [gow] (2) Make <video> delay the load event until the first frame is available.
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Author: ianh
Date: 2009-03-25 01:40:03 -0700 (Wed, 25 Mar 2009)
New Revision: 2907

Modified:
   index
   source
Log:
[gow] (2) Fix race conditions in the <video> load mechanism.

Modified: index
===================================================================
--- index	2009-03-25 07:11:43 UTC (rev 2906)
+++ index	2009-03-25 08:40:03 UTC (rev 2907)
@@ -19129,9 +19129,8 @@
   these must return a new <code><a href=#htmlaudioelement>HTMLAudioElement</a></code> object (a new
   <code><a href=#audio>audio</a></code> element). If the <var title="">src</var> argument
   is present, the object created must have its <code title=dom-media-src><a href=#dom-media-src>src</a></code> content attribute set to the
-  provided value, and the user agent must asynchronously invoke the
-  object's <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource
-  selection algorithm</a> before returning.</p>
+  provided value, and the user agent must invoke the object's <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
+  algorithm</a> before returning.</p>
 
   </div>
 
@@ -19774,7 +19773,7 @@
 
     </ol></li>
 
-   <li><p>Asynchronously invoke the <a href=#media-element>media element</a>'s <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
+   <li><p>Invoke the <a href=#media-element>media element</a>'s <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
    algorithm</a>.</li>
 
    <li>
@@ -19786,8 +19785,10 @@
 
   </ol><p>The <dfn id=concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
   algorithm</dfn> for a <a href=#media-element>media element</a> is as follows. This
-  algorithm is always invoked asynchronously, meaning that it runs in
-  the background with scripts and other <a href=#concept-task title=concept-task>tasks</a> running in parallel.</p>
+  algorithm is always invoked synchronously, but one of the first
+  steps in the algorithm is to return and continue running the
+  remaining steps asynchronously, meaning that it runs in the
+  background with scripts and other <a href=#concept-task title=concept-task>tasks</a> running in parallel.</p>
 
   <ol><li>
 
@@ -19796,18 +19797,37 @@
 
     <ol><li><p>Set the <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code> to <code title=dom-media-NETWORK_NO_SOURCE><a href=#dom-media-network_no_source>NETWORK_NO_SOURCE</a></code>.</li>
 
+     <li><p>Run the remainder of the <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
+     algorithm</a> steps asynchronously, allowing the <a href=#concept-task title=concept-task>task</a> that invoked this algorithm to
+     continue.</li>
+
      <li><p>While the <a href=#media-element>media element</a> has neither a <code title=attr-media-src><a href=#attr-media-src>src</a></code> attribute nor any
-     <code><a href=#the-source-element>source</a></code> element children, wait. (This steps might
-     wait forever.)</li>
+     <code><a href=#the-source-element>source</a></code> element children, wait. (This step might wait
+     forever.)</li>
 
+     <li><p>Before the <a href=#concept-task title=concept-task>task</a> that set
+     the <code title=attr-media-src><a href=#attr-media-src>src</a></code> attribute or inserted
+     the <code><a href=#the-source-element>source</a></code> element has a chance to complete, set the
+     <a href=#media-element>media element</a>'s <a href=#delaying-the-load-event-flag>delaying-the-load-event
+     flag</a> to true (this <a href=#delay-the-load-event title="delay the load
+     event">delays the load event</a>), and set its <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code> to <code title=dom-media-NETWORK_LOADING><a href=#dom-media-network_loading>NETWORK_LOADING</a></code>.</li>
+
+    </ol><p>Otherwise, run these substeps:</p>
+
+    <ol><li><p>Set the <a href=#media-element>media element</a>'s
+     <a href=#delaying-the-load-event-flag>delaying-the-load-event flag</a> to true (this <a href=#delay-the-load-event title="delay the load event">delays the load event</a>), and
+     set its <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code>
+     to <code title=dom-media-NETWORK_LOADING><a href=#dom-media-network_loading>NETWORK_LOADING</a></code>.</li>
+
+     <li><p>Run the remainder of the <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
+     algorithm</a> steps asynchronously, allowing the <a href=#concept-task title=concept-task>task</a> that invoked this algorithm to
+     continue.</li>
+
     </ol></li>
 
-   <li><p>Set the element's <a href=#delaying-the-load-event-flag>delaying-the-load-event flag</a>
-   to true. This <a href=#delay-the-load-event title="delay the load event">delays the load
-   event</a>.</li>
+   <li><p class=note>By this point, the algorithm is running
+   asynchronously.</li>
 
-   <li><p>Set the <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code> to <code title=dom-media-NETWORK_LOADING><a href=#dom-media-network_loading>NETWORK_LOADING</a></code>.</li>
-
    <li><p><a href=#queue-a-task>Queue a task</a> to <a href=#fire-a-progress-event>fire a progress
    event</a> called <code title=event-loadstart><a href=#event-loadstart>loadstart</a></code>
    at the <a href=#media-element>media element</a>.</li>
@@ -19976,10 +19996,12 @@
      node other than the end of the list. (This step might wait
      forever.)</li>
 
-     <li><p>Set the element's <a href=#delaying-the-load-event-flag>delaying-the-load-event
+     <li><p>Before the <a href=#concept-task title=concept-task>task</a> that
+     inserted the <code><a href=#the-source-element>source</a></code> element has a chance to
+     complete, set the element's <a href=#delaying-the-load-event-flag>delaying-the-load-event
      flag</a> back to true. This <a href=#delay-the-load-event title="delay the load
-     event">delays the load event</a> again, in case it hasn't gone
-     been fired yet.</li>
+     event">delays the load event</a> again, in case it hasn't been
+     fired yet.</li>
 
      <li><p>Jump back to the step labeled <i>search loop</i>.</li>
 
@@ -20292,9 +20314,9 @@
 
   </ol><p>If a <a href=#media-element>media element</a> whose <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code> has the value
   <code title=dom-media-NETWORK_EMPTY><a href=#dom-media-network_empty>NETWORK_EMPTY</a></code> is <a href=#insert-an-element-into-a-document title="insert an element into a document">inserted into a
-  document</a>, the user agent must asynchronously invoke the
-  <a href=#media-element>media element</a>'s <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
-  algorithm</a>.</p>
+  document</a>, the user agent must invoke the <a href=#media-element>media
+  element</a>'s <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource
+  selection algorithm</a>.</p>
 
   </div>
 
@@ -20942,8 +20964,7 @@
 
   <ol><li><p>If the <a href=#media-element>media element</a>'s <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code> attribute has
    the value <code title=dom-media-NETWORK_EMPTY><a href=#dom-media-network_empty>NETWORK_EMPTY</a></code>, then the user
-   agent must asynchronously invoke the <a href=#media-element>media element</a>'s
-   <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
+   agent must invoke the <a href=#media-element>media element</a>'s <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
    algorithm</a>.</li>
 
    <li>
@@ -20999,8 +21020,7 @@
 
   <ol><li><p>If the <a href=#media-element>media element</a>'s <code title=dom-media-networkState><a href=#dom-media-networkstate>networkState</a></code> attribute has
    the value <code title=dom-media-NETWORK_EMPTY><a href=#dom-media-network_empty>NETWORK_EMPTY</a></code>, then the user
-   agent must asynchronously invoke the <a href=#media-element>media element</a>'s
-   <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
+   agent must invoke the <a href=#media-element>media element</a>'s <a href=#concept-media-load-algorithm title=concept-media-load-algorithm>resource selection
    algorithm</a>.</li>
 
    <li><p>If the <a href=#media-element>media element</a>'s <code title=dom-media-paused><a href=#dom-media-paused>paused</a></code> attribute is false, it must

Modified: source
===================================================================
--- source	2009-03-25 07:11:43 UTC (rev 2906)
+++ source	2009-03-25 08:40:03 UTC (rev 2907)
@@ -20604,9 +20604,9 @@
   <code>audio</code> element). If the <var title="">src</var> argument
   is present, the object created must have its <code
   title="dom-media-src">src</code> content attribute set to the
-  provided value, and the user agent must asynchronously invoke the
-  object's <span title="concept-media-load-algorithm">resource
-  selection algorithm</span> before returning.</p>
+  provided value, and the user agent must invoke the object's <span
+  title="concept-media-load-algorithm">resource selection
+  algorithm</span> before returning.</p>
 
   </div>
 
@@ -21342,7 +21342,7 @@
 
    </li>
 
-   <li><p>Asynchronously invoke the <span>media element</span>'s <span
+   <li><p>Invoke the <span>media element</span>'s <span
    title="concept-media-load-algorithm">resource selection
    algorithm</span>.</li>
 
@@ -21357,8 +21357,10 @@
 
   <p>The <dfn title="concept-media-load-algorithm">resource selection
   algorithm</dfn> for a <span>media element</span> is as follows. This
-  algorithm is always invoked asynchronously, meaning that it runs in
-  the background with scripts and other <span
+  algorithm is always invoked synchronously, but one of the first
+  steps in the algorithm is to return and continue running the
+  remaining steps asynchronously, meaning that it runs in the
+  background with scripts and other <span
   title="concept-task">tasks</span> running in parallel.</p>
 
   <ol>
@@ -21375,23 +21377,52 @@
      title="dom-media-networkState">networkState</code> to <code
      title="dom-media-NETWORK_NO_SOURCE">NETWORK_NO_SOURCE</code>.</p></li>
 
+     <li><p>Run the remainder of the <span
+     title="concept-media-load-algorithm">resource selection
+     algorithm</span> steps asynchronously, allowing the <span
+     title="concept-task">task</span> that invoked this algorithm to
+     continue.</p></li>
+
      <li><p>While the <span>media element</span> has neither a <code
      title="attr-media-src">src</code> attribute nor any
-     <code>source</code> element children, wait. (This steps might
-     wait forever.)</p></li>
+     <code>source</code> element children, wait. (This step might wait
+     forever.)</p></li>
 
+     <li><p>Before the <span title="concept-task">task</span> that set
+     the <code title="attr-media-src">src</code> attribute or inserted
+     the <code>source</code> element has a chance to complete, set the
+     <span>media element</span>'s <span>delaying-the-load-event
+     flag</span> to true (this <span title="delay the load
+     event">delays the load event</span>), and set its <code
+     title="dom-media-networkState">networkState</code> to <code
+     title="dom-media-NETWORK_LOADING">NETWORK_LOADING</code>.</p></li>
+
     </ol>
 
+    <p>Otherwise, run these substeps:</p>
+
+    <ol>
+
+     <li><p>Set the <span>media element</span>'s
+     <span>delaying-the-load-event flag</span> to true (this <span
+     title="delay the load event">delays the load event</span>), and
+     set its <code title="dom-media-networkState">networkState</code>
+     to <code
+     title="dom-media-NETWORK_LOADING">NETWORK_LOADING</code>.</p></li>
+
+     <li><p>Run the remainder of the <span
+     title="concept-media-load-algorithm">resource selection
+     algorithm</span> steps asynchronously, allowing the <span
+     title="concept-task">task</span> that invoked this algorithm to
+     continue.</p></li>
+
+    </ol>
+
    </li>
 
-   <li><p>Set the element's <span>delaying-the-load-event flag</span>
-   to true. This <span title="delay the load event">delays the load
-   event</span>.</p></li>
+   <li><p class="note">By this point, the algorithm is running
+   asynchronously.</p></li>
 
-   <li><p>Set the <code
-   title="dom-media-networkState">networkState</code> to <code
-   title="dom-media-NETWORK_LOADING">NETWORK_LOADING</code>.</p></li>
-
    <li><p><span>Queue a task</span> to <span>fire a progress
    event</span> called <code title="event-loadstart">loadstart</code>
    at the <span>media element</span>.</p></li>
@@ -21601,10 +21632,12 @@
      node other than the end of the list. (This step might wait
      forever.)</p></li>
 
-     <li><p>Set the element's <span>delaying-the-load-event
+     <li><p>Before the <span title="concept-task">task</span> that
+     inserted the <code>source</code> element has a chance to
+     complete, set the element's <span>delaying-the-load-event
      flag</span> back to true. This <span title="delay the load
-     event">delays the load event</span> again, in case it hasn't gone
-     been fired yet.</p></li>
+     event">delays the load event</span> again, in case it hasn't been
+     fired yet.</p></li>
 
      <li><p>Jump back to the step labeled <i>search loop</i>.</p></li>
 
@@ -21997,10 +22030,9 @@
   title="dom-media-networkState">networkState</code> has the value
   <code title="dom-media-NETWORK_EMPTY">NETWORK_EMPTY</code> is <span
   title="insert an element into a document">inserted into a
-  document</span>, the user agent must asynchronously invoke the
-  <span>media element</span>'s <span
-  title="concept-media-load-algorithm">resource selection
-  algorithm</span>.</p>
+  document</span>, the user agent must invoke the <span>media
+  element</span>'s <span title="concept-media-load-algorithm">resource
+  selection algorithm</span>.</p>
 
   </div>
 
@@ -22766,8 +22798,8 @@
    title="dom-media-networkState">networkState</code> attribute has
    the value <code
    title="dom-media-NETWORK_EMPTY">NETWORK_EMPTY</code>, then the user
-   agent must asynchronously invoke the <span>media element</span>'s
-   <span title="concept-media-load-algorithm">resource selection
+   agent must invoke the <span>media element</span>'s <span
+   title="concept-media-load-algorithm">resource selection
    algorithm</span>.</p></li>
 
    <li>
@@ -22842,8 +22874,8 @@
    title="dom-media-networkState">networkState</code> attribute has
    the value <code
    title="dom-media-NETWORK_EMPTY">NETWORK_EMPTY</code>, then the user
-   agent must asynchronously invoke the <span>media element</span>'s
-   <span title="concept-media-load-algorithm">resource selection
+   agent must invoke the <span>media element</span>'s <span
+   title="concept-media-load-algorithm">resource selection
    algorithm</span>.</p></li>
 
    <li><p>If the <span>media element</span>'s <code
Previous message: [html5] r2906 - [e] (0) v2 note
Next message: [html5] r2908 - [gow] (2) Make <video> delay the load event until the first frame is available.
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
More information about the Commit-Watchers mailing list