html5/spec Overview.html,1.1736,1.1737

Update of /sources/public/html5/spec
In directory hutz:/tmp/cvs-serv9368

Modified Files:
	Overview.html 
Log Message:
Make <img src=''> a special case. (credit: bz) (whatwg r2566)

Index: Overview.html
===================================================================
RCS file: /sources/public/html5/spec/Overview.html,v
retrieving revision 1.1736
retrieving revision 1.1737
diff -u -d -r1.1736 -r1.1737
--- Overview.html	24 Dec 2008 10:27:02 -0000	1.1736
+++ Overview.html	24 Dec 2008 11:04:28 -0000	1.1737
@@ -11882,7 +11882,9 @@
   <code><a href=#the-img-element>img</a></code> element's <a href=#fallback-content>fallback content</a>.<p>The <code title=attr-img-src><a href=#attr-img-src>src</a></code> attribute must be
   present, and must contain a <a href=#valid-url>valid URL</a> referencing a
   non-interactive, optionally animated, image resource that is neither
-  paged nor scripted.<p class=note>Images can thus be static bitmaps (e.g. PNGs, GIFs,
+  paged nor scripted. If the <i>base URI of the element</i> is the
+  same as <a href=#the-document-s-address>the document's address</a>, then the <code title=attr-img-src><a href=#attr-img-src>src</a></code> attribute's value must not be the
+  empty string.<p class=note>Images can thus be static bitmaps (e.g. PNGs, GIFs,
   JPEGs), single-page vector documents (single-page PDFs, XML files
   with an SVG root element), animated bitmaps (APNGs, animated GIFs),
   animated vector graphics (XML files with an SVG root element that
@@ -11900,7 +11902,13 @@
   user agent must <a href=#fetch>fetch</a> the resource specifed by the
   <code title=attr-img-src><a href=#attr-img-src>src</a></code> attribute's value, unless the
   user agent cannot support images, or its support for images has been
-  disabled, or the user agent only fetches elements on demand.</p><!-- Note how this does NOT happen when the base URL changes. --><p>Fetching the image must <a href=#delay-the-load-event>delay the <code title=event-load>load</code> event</a>.<p class=warning>This, unfortunately, can be used to perform a
+  disabled, or the user agent only fetches elements on demand, or the
+  element's <code title=attr-img-src><a href=#attr-img-src>src</a></code> attribute has a
+  value that is an <i>ignored self-reference</i>.</p><!-- Note how
+  this does NOT happen when the base URL changes. --><p>The <code title=attr-img-src><a href=#attr-img-src>src</a></code> attribute's value is an
+  <i>ignored self-reference</i> if its value is the empty string, and
+  the <i>base URI of the element</i> is the same as <a href=#the-document-s-address>the
+  document's address</a>.<p>Fetching the image must <a href=#delay-the-load-event>delay the <code title=event-load>load</code> event</a>.<p class=warning>This, unfortunately, can be used to perform a
   rudimentary port scan of the user's local network (especially in
   conjunction with scripting, though scripting isn't actually
   necessary to carry out such an attack). User agents may implement
@@ -11913,7 +11921,11 @@
   rendering of images; in such cases, each <a href=#concept-task title=concept-task>task</a> that is <a href=#queue-a-task title="queue a
   task">queued</a> by the <a href=#networking-task-source>networking task source</a> while
   the image is being <a href=#fetch title=fetch>fetched</a> must update
-  the presentation of the image appropriately.<p>Whether the image is fetched successfully or not (e.g. whether
+  the presentation of the image appropriately.<p>If the image was not fetched (e.g. because the UA's image support
+  is disabled, or because the <code title=attr-img-src><a href=#attr-img-src>src</a></code>
+  attribute's value is an <i>ignored self-reference</i>), or if the
+  conditions in the previous paragraph are not met, then the image is
+  <em>not</em> <i>available</i>.<p>Whether the image is fetched successfully or not (e.g. whether
   the response code was a 2xx code <a href=#concept-http-equivalent-codes title=concept-http-equivalent-codes>or equivalent</a>) must be
   ignored when determining the image's type and whether it is a valid
   image.<p class=note>This allows servers to return images with error
@@ -11948,9 +11960,9 @@
     the content, redundant with some other information in the
     document.</p>
 
-    <p>If the image is <i>available</i> and the user agent is configured to
-    display that image, then the element represents the image
-    specified by the <code title=attr-img-src><a href=#attr-img-src>src</a></code>
+    <p>If the image is <i>available</i> and the user agent is
+    configured to display that image, then the element represents the
+    image specified by the <code title=attr-img-src><a href=#attr-img-src>src</a></code>
     attribute.</p>
 
     <p>Otherwise, the element represents nothing, and may be omitted

Received on Wednesday, 24 December 2008 11:04:39 UTC