[not part of build]

Added rough cut of pref code for memory cache device to get cache size, and implemented simple eviction method.

Restructured nsCacheEntryDescriptor to add SecurityInfo attribute.  Created nsTransportWrapper as nested class (and member) that addrefs the descriptor instead of itself (like nsPipe).  Also rename nsCacheOutputStream to nsOutputStreamWrapper and made it a nested class as well.


git-svn-id: svn://10.0.0.236/trunk@88816 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/netwerk/cache/src/nsMemoryCacheDevice.cpp

@@ -25,11 +25,21 @@
 #include "nsICacheService.h"
 #include "nsIComponentManager.h"
 #include "nsNetCID.h"
+#include "nsIObserverService.h"
+#include "nsIPref.h"
+
 
 static NS_DEFINE_CID(kStorageTransportCID, NS_STORAGETRANSPORT_CID);
 
+const char *gMemoryCacheSizePref = "browser.cache.memory_cache_size";
+
 nsMemoryCacheDevice::nsMemoryCacheDevice()
-    : mCurrentTotal(0)
+    : mHardLimit(0),
+      mSoftLimit(0),
+      mTotalSize(0),
+      mInactiveSize(0),
+      mEntryCount(0),
+      mMaxEntryCount(0)
 {
     PR_INIT_CLIST(&mEvictionList);
 }
@@ -37,6 +47,30 @@ nsMemoryCacheDevice::nsMemoryCacheDevice()
 nsMemoryCacheDevice::~nsMemoryCacheDevice()
 {
     // XXX dealloc all memory
+    nsresult rv;
+    NS_WITH_SERVICE(nsIPref, prefs, NS_PREF_CONTRACTID, &rv);
+    if (NS_SUCCEEDED(rv)) {
+        prefs->UnregisterCallback(gMemoryCacheSizePref, MemoryCacheSizeChanged, this);
+    }
+}
+
+
+int PR_CALLBACK
+nsMemoryCacheDevice::MemoryCacheSizeChanged(const char * pref, void * closure)
+{
+    nsresult  rv;
+    PRUint32   softLimit = 0;
+    nsMemoryCacheDevice * device = (nsMemoryCacheDevice *)closure;
+
+    NS_WITH_SERVICE(nsIPref, prefs, NS_PREF_CONTRACTID, &rv);
+    if (NS_FAILED(rv))  return rv;
+
+    rv = prefs->GetIntPref(gMemoryCacheSizePref, (PRInt32 *)&softLimit);
+    
+    PRUint32 hardLimit = softLimit + 1024*1024*2;  // XXX find better limit than +2Meg
+    rv = device->AdjustMemoryLimits(softLimit, hardLimit);
+
+    return 0; // XXX what are we supposed to return?
 }
 
 
@@ -48,6 +82,23 @@ nsMemoryCacheDevice::Init()
     rv = mMemCacheEntries.Init();
 
     // XXX read user prefs for memory cache limits
+    NS_WITH_SERVICE(nsIPref, prefs, NS_PREF_CONTRACTID, &rv);
+    if (NS_FAILED(rv))  return rv;
+
+    rv = prefs->RegisterCallback(gMemoryCacheSizePref, MemoryCacheSizeChanged, this);
+    if (NS_FAILED(rv))  return rv;
+
+    // Initialize the pref
+    MemoryCacheSizeChanged(gMemoryCacheSizePref, this);
+
+    // Register as a memory pressure observer
+    NS_WITH_SERVICE(nsIObserverService,
+                    observerService,
+                    NS_OBSERVERSERVICE_CONTRACTID, &rv);
+    if (NS_SUCCEEDED(rv)) {
+        // XXX rv = observerServcie->AddObserver(this, NS_MEMORY_PRESSURE_TOPIC);
+    }
+    // Ignore failure of memory pressure registration
 
     return rv;
 }
@@ -165,7 +216,56 @@ nsMemoryCacheDevice::OnDataSizeChange( nsCacheEntry * entry, PRInt32 deltaSize)
     return NS_OK;
 }
 
+
+nsresult
+nsMemoryCacheDevice::AdjustMemoryLimits(PRUint32  softLimit, PRUint32  hardLimit)
+{
+    mSoftLimit = softLimit;
+    mHardLimit = hardLimit;
+
+    if ((mTotalSize > mHardLimit) || (mInactiveSize > softLimit)) {
+        // XXX rv = EvictEntries();
+    }
+    return NS_OK;
+}
+
+
+nsresult
+nsMemoryCacheDevice::EvictEntries(void)
+{
+    nsCacheEntry * entry;
+    nsresult       rv = NS_OK;
+
+    entry = (nsCacheEntry *)PR_LIST_HEAD(&mEvictionList);
+    while (entry != &mEvictionList) {
+        if (entry->IsInUse()) {
+            entry = (nsCacheEntry *)PR_NEXT_LINK(entry);
+            continue;
+        }
+
+        // remove entry from our hashtable
+        rv = mMemCacheEntries.RemoveEntry(entry);
+        NS_ASSERTION(NS_SUCCEEDED(rv), "RemoveEntry() failed?");
+
+        // remove entry from the eviction list
+        PR_REMOVE_AND_INIT_LINK(entry);
+        
+        // update statistics
+        PRUint32 memoryRecovered = entry->DataSize() + entry->MetaDataSize();
+        mTotalSize    -= memoryRecovered;
+        mInactiveSize -= memoryRecovered;
+        --mEntryCount;
+        delete entry;
+
+        if ((mTotalSize < mHardLimit) && (mInactiveSize < mSoftLimit))
+            break;
+    }
+
+    return NS_OK;
+}
+
+
+
 // XXX need methods for enumerating entries
 
 
-// XXX check entry->IsInUse() before evicting.