fixes bug 321833 "Clearing the cache prevents disk cache from working" r=mconnor, alfredkayser

browser/base/content/sanitize.js

@@ -98,50 +98,9 @@ Sanitizer.prototype = {
         const ci = Components.interfaces;
         var cacheService = cc["@mozilla.org/network/cache-service;1"]
                              .getService(ci.nsICacheService);
-
-        // Here we play dirty, trying to brutally wipe out all the cache files 
-        // even if the disk cache device has gone away (if it is still with us,
-        // our removal attempt will fail because the directory is locked,
-        // and we fall back to the "nice" way below)
-        
-        var cacheDir;
-        // Look at nsCacheProfilePrefObserver::ReadPrefs()
-        // and nsDiskCacheDevice::SetCacheParentDirectory()
-        // for details on how we guess the cache directory
         try {
-          cacheDir = cc["@mozilla.org/preferences-service;1"]
-                       .getService(ci.nsIPrefBranch)
-                       .getComplexValue("browser.cache.disk.parent_directory",
-                                        ci.nsILocalFile);
-        } catch(er) {
-          const dirServ = cc["@mozilla.org/file/directory_service;1"]
-                            .getService(ci.nsIProperties);
-          try {
-            cacheDir = dirServ.get("cachePDir",ci.nsILocalFile);
-          } catch(er) {
-            cacheDir = dirServ.get("ProfLD",ci.nsILocalFile);
-          }
-        }
-        
-        if (cacheDir) {
-          // Here we try to prevent the "phantom Cache.Trash" issue
-          // reported in bug #296256
-          cacheDir.append("Cache.Trash");
-          try {
-            cacheDir.remove(true);
-          } catch(er) {}
-          cacheDir = cacheDir.parent;
-          cacheDir.append("Cache");
-          try {
-           cacheDir.remove(true);
-          } catch(er) {}
-        }
-        
-        try {
-          // The "nice" way
           cacheService.evictEntries(ci.nsICache.STORE_ANYWHERE);
         } catch(er) {}
-        
       },
       
       get canClear()

netwerk/cache/src/nsCacheService.cpp

@@ -356,7 +356,7 @@ nsCacheProfilePrefObserver::ReadPrefs(nsIPrefBranch* branch)
                     if (NS_SUCCEEDED(rv)) {
                         PRBool exists;
                         if (NS_SUCCEEDED(profDir->Exists(&exists)) && exists)
-                            DeleteDir(profDir, PR_FALSE);
+                            DeleteDir(profDir, PR_FALSE, PR_FALSE);
                     }
                 }
             }

netwerk/cache/src/nsDeleteDir.cpp

@@ -48,7 +48,7 @@ PR_STATIC_CALLBACK(void) DeleteDirThreadFunc(void *arg)
   NS_RELEASE(dir);
 }
 
-nsresult DeleteDir(nsIFile *dirIn, PRBool moveToTrash)
+nsresult DeleteDir(nsIFile *dirIn, PRBool moveToTrash, PRBool sync)
 {
   nsresult rv;
   nsCOMPtr<nsIFile> trash, dir;
@@ -92,16 +92,23 @@ nsresult DeleteDir(nsIFile *dirIn, PRBool moveToTrash)
   nsIFile *trashRef = nsnull;
   trash.swap(trashRef);
 
-  // now, invoke the worker thread
-  PRThread *thread = PR_CreateThread(PR_USER_THREAD,
-                                     DeleteDirThreadFunc,
-                                     trashRef,
-                                     PR_PRIORITY_LOW,
-                                     PR_GLOBAL_THREAD,
-                                     PR_UNJOINABLE_THREAD,
-                                     0);
-  if (!thread)
-    return NS_ERROR_UNEXPECTED;
+  if (sync)
+  {
+    DeleteDirThreadFunc(trashRef);
+  }
+  else
+  {
+    // now, invoke the worker thread
+    PRThread *thread = PR_CreateThread(PR_USER_THREAD,
+                                       DeleteDirThreadFunc,
+                                       trashRef,
+                                       PR_PRIORITY_LOW,
+                                       PR_GLOBAL_THREAD,
+                                       PR_UNJOINABLE_THREAD,
+                                       0);
+    if (!thread)
+      return NS_ERROR_UNEXPECTED;
+  }
 
   return NS_OK;
 }

netwerk/cache/src/nsDeleteDir.h

@@ -56,8 +56,11 @@ class nsIFile;
  *
  * If the moveToTrash parameter is false, then the given directory is deleted
  * directly.
+ *
+ * If the sync flag is true, then the delete operation runs to completion
+ * before this function returns.  Otherwise, deletion occurs asynchronously.
  */
-NS_HIDDEN_(nsresult) DeleteDir(nsIFile *dir, PRBool moveToTrash);
+NS_HIDDEN_(nsresult) DeleteDir(nsIFile *dir, PRBool moveToTrash, PRBool sync);
 
 /**
  * This routine returns the trash directory corresponding to the given 

netwerk/cache/src/nsDiskCacheDevice.cpp

@@ -385,14 +385,29 @@ error_exit:
 nsresult
 nsDiskCacheDevice::Shutdown()
 {
-    return Shutdown_Private(PR_TRUE);
+    nsresult rv = Shutdown_Private(PR_TRUE);
+    if (NS_FAILED(rv))
+        return rv;
+
+    if (mCacheDirectory) {
+        // delete any trash files left-over before shutting down.
+        nsCOMPtr<nsIFile> trashDir;
+        GetTrashDir(mCacheDirectory, &trashDir);
+        if (trashDir) {
+            PRBool exists;
+            if (NS_SUCCEEDED(trashDir->Exists(&exists)) && exists)
+                DeleteDir(trashDir, PR_FALSE, PR_TRUE);
+        }
+    }
+
+    return NS_OK;
 }
 
 
 nsresult
 nsDiskCacheDevice::Shutdown_Private(PRBool  flush)
 {
-        if (Initialized()) {
+    if (Initialized()) {
         // check cache limits in case we need to evict.
         EvictDiskCacheEntries((PRInt32)mCacheCapacity);
 
@@ -834,7 +849,7 @@ nsDiskCacheDevice::OpenDiskCache()
         rv = mCacheMap->Open(mCacheDirectory);        
         // move "corrupt" caches to trash
         if (rv == NS_ERROR_FILE_CORRUPTED) {
-            rv = DeleteDir(mCacheDirectory, PR_TRUE);
+            rv = DeleteDir(mCacheDirectory, PR_TRUE, PR_FALSE);
             if (NS_FAILED(rv))
                 return rv;
             exists = PR_FALSE;
@@ -858,7 +873,7 @@ nsDiskCacheDevice::OpenDiskCache()
         if (trashDir) {
             PRBool exists;
             if (NS_SUCCEEDED(trashDir->Exists(&exists)) && exists)
-                DeleteDir(trashDir, PR_FALSE);
+                DeleteDir(trashDir, PR_FALSE, PR_FALSE);
         }
     }
 
@@ -876,8 +891,10 @@ nsDiskCacheDevice::ClearDiskCache()
     if (NS_FAILED(rv))
         return rv;
 
-    rv = DeleteDir(mCacheDirectory, PR_TRUE);
-    if (NS_FAILED(rv))
+    // If the disk cache directory is already gone, then it's not an error if
+    // we fail to delete it ;-)
+    rv = DeleteDir(mCacheDirectory, PR_TRUE, PR_FALSE);
+    if (NS_FAILED(rv) && rv != NS_ERROR_FILE_TARGET_DOES_NOT_EXIST)
         return rv;
 
     return Init();