73441 - New cache needs "Clear" functionality

Status: VERIFIED FIXED

(Core :: Networking: Cache, defect)

Description

[Conrad Carlen (not reading bugmail)]

The old cache had the nsINetDataCacheManager::Clear() method. This is needed for
programs which want to have a "Clear Disk Cache" feature. There isn't an
equivalent method on the new cache.

Comment 1

[R.K.Aa.]

perhaps this blocks bug 73062?

Comment 2

[Judson Valeski]

what interface would this hang off of?

Comment 3

[gordon]

We need a couple of different "clear" interfaces.  A cache client (like http or 
imgLib) might want to clear all their entries, or a user might want to clear an 
entire cache device (usually to fix some other bug - whatever, okay).  The "clear 
device" probably needs to be on nsICacheService, passing the deviceID to clear.  
The "clear entries for client" could be on the nsICacheSession.  It may be able 
to use the visitor interface to selectively remove cache entries (imgLib removing 
chrome entries after a theme switch).

Comment 4

[Patrick C. Beard]

Initial implementation of disk cache clearing checked in on DISKCACHE1_BRANCH. 
Enclosing a patch to pref-cache.js that uses new cache service to do this.

Comment 5

[Patrick C. Beard]

Attachment: Patch to pref-cache.js to use new cache service to clear disk cache.

Comment 6

[gordon]

*** Bug 73062 has been marked as a duplicate of this bug. ***

Comment 7

[Patrick C. Beard]

Attachment: Updated patch to use new cache API from JavaScript.

Comment 8

[gordon]

Chris, Darin: can I get a review and superreview on Patrick's patch to the pref-
cache.js file?

Comment 9

[Darin Fisher]

r/sr=darin

Comment 10

[gordon]

I also had to add:

prefixLen = (clientID ? nsCRT::strlen(clientID) : 0);

to nsMemoryCacheDevice.cpp, because it would abort on linux otherwise.  I think 
this is a bug in nsCRT::strlen().

Closing this bug as FIXED.  I'd be happy to open another bug on nsCRT::strlen() 
if you folks agree.

Comment 11

[Peter "jag" Annema]

Since you removed the code that needed the |const nsINetDataCacheManager| you
could've removed that const. And it's bad form to use 4 space indent in a file
which is 2 space indent... While in Rome etc.

Comment 12

[Peter "jag" Annema]

+  var classID = Components.classes["@mozilla.org/network/cache-service;1"];
+  var cacheService = classID.getService(Components.interfaces.nsICacheService);

So, the thing isn't really a classID... It's a class, so something like:

+  var cacheClass = Components.classes["@mozilla.org/network/cache-service;1"];

would've been more appropriate.

But why not go with the style that already was in there and use:

+  var cacheService = Components.classes["@mozilla.org/network/cache-service;1"]
+                              
.getService(Components.interfaces.nsICacheService);

?

Comment 13

[Darin Fisher]

gordon: the added check around nsCRT::strlen is necessary on linux because
the function is just a wrapper around the native strlen.  if it were a wrapper
around PL_strlen, then this check would not be necessary.

Comment 14

[gordon]

Well, gee.  Why don't we just use PL_strlen() then?  Why use nsCRT::strlen()?  
Why do we need two?

Comment 15

[Tom Everingham]

verified