LEGAL
author Emilio Cobos Álvarez <emilio@crisal.io>
Fri, 22 Mar 2019 22:26:53 +0000
changeset 465793 88b6e96d82153bf333e1a309f5ae384906168883
parent 1 9b2a99adc05e53cd4010de512f50118594756650
permissions -rw-r--r--
Bug 1531333 - Fix <svg:use> cycle detection. r=longsonr With the current code we'll eventually detect the cycle, but will take much more, creating many shadow trees unnecessarily. Take for example the following: <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="133" height="232774"> <style> symbol { display: block } </style> <symbol id="svg-sprite" viewBox="0 0 133 230866"> <title>svg-sprite</title> <symbol id="svg-sprite" viewBox="0 0 133 230866"> <title>svg-sprite</title> <use xlink:href="#svg-sprite" width="500" height="500" /> </symbol> <use xlink:href="#svg-sprite" y="1601" width="133" height="228958" /> </symbol> <use xlink:href="#svg-sprite" y="1601" width="133" height="230866" /> </svg> Before this patch, we'd create an svg use element subtree for #svg-sprite. That subtree will contain two other <use> elements, one under the <symbol>, one not under it. Both point to #svg-sprite, but we fail to detect we're an ancestor since the element #svg-sprite we're looking at is the clone of the #svg-sprite element. Thus we need to take a look at mOriginal instead (which is the <use> element under #svg-sprite) rather than at the clone. Yeah, I had to draw the trees, it's messy :) Blink and WebKit do something slightly different (they check the element id directly[1]). That's not 100% correct, since you can have multiple elements with the same ID. [1]: https://cs.chromium.org/chromium/src/third_party/blink/renderer/core/svg/svg_use_element.cc?l=560&rcl=861855dcb8c39ba8d42497247d433277858df79b Differential Revision: https://phabricator.services.mozilla.com/D24565

Please be apprised of the following Legal Notices:

A) The U.S. District Court for the Eastern District of Virginia has
ruled that the Netscape Navigator code does not infringe Wang's U.S.
Patent No. 4,751,669 ("the '669 Patent") because: 1) HTML is not
Videotex as defined by the '669 patent; 2) web servers are not central
suppliers; and 3) Navigator does not "connect," as defined by the '669
Patent, to web servers on the Internet. Wang may appeal this decision to
the Federal Circuit. Wang contended that its Patent disclosing a
"Videotex" system, is infringed by the following functionality in the
Netscape Navigator code: 1) the animated logo and status line indicators
--See Claims 1,8 and 9; 2) the "File Save As" function --See Claims
23-27; 3) Bookmarks and Rename Bookmarks in the Properties window --See
Claims 20-22; 4) storing HTML, GIF, and JPEG files and adding filename
extensions --See Claim 38

B) Intermind owns pending U.S. patent applications on communications
systems which employ metadata ("channel objects") to define a control
structure for information transfer. The Netscape code does not infringe
as released; however, modifications which utilize channel objects as
described by Intermind should be considered carefully. The following is
a statement from Intermind: "Intermind's claims fundamentally involve
the use of a control structure to automate communications. ...The
essence of Intermind's top claim is that two devices sender and receiver
have persistent storage, communicate over a network, and exchange a
control structure including metadata which describes: 1) what
information is to be updated, 2) when to update this information, and 3)
how to transfer the updated information. In addition, at least the
receiving device must be able to process the metadata in order to
perform the update determination and transfer. Any digital
communications system which incorporates all of these elements will be
covered by Intermind's patents." See Intermind.com.

C) Stac, Inc., and its licensing agent Hi/fn, own several patents which
disclose data compression methods implementing an LZS compression
algorithm, including U.S. Patent Nos. 4,701,745 and 5,016, 009 ("the
Stac Patents"). The Netscape Communicator code does not perform
compression. If you modify the Netscape source code to perform
compression, please take notice of the Stac Patents.

D) Netscape Communications Corporation ("Netscape") does not guarantee
that any source code or executable code available from the mozilla.org
domain is Year 2000 compliant.