Mozilla/mozilla/netwerk/cache/src/nsMemoryCacheDevice.cpp
2001-07-18 23:37:17 +00:00

456 lines
12 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Mozilla Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is nsMemoryCacheDevice.cpp, released February 22, 2001.
*
* The Initial Developer of the Original Code is Netscape Communications
* Corporation. Portions created by Netscape are
* Copyright (C) 2001 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
* Gordon Sheridan, <gordon@netscape.com>
* Patrick C. Beard <beard@netscape.com>
*/
#include "nsMemoryCacheDevice.h"
#include "nsCacheService.h"
#include "nsICacheService.h"
#include "nsIComponentManager.h"
#include "nsIServiceManager.h"
#include "nsNetCID.h"
#include "nsIObserverService.h"
#include "nsIPref.h"
#include "nsICacheVisitor.h"
#include "nsITransport.h"
#include "signal.h"
static NS_DEFINE_CID(kStorageTransportCID, NS_STORAGETRANSPORT_CID);
const char *gMemoryDeviceID = "memory";
nsMemoryCacheDevice::nsMemoryCacheDevice()
: mEvictionThreshold(40 * 1024),
mHardLimit(4 * 1024 * 1024), // set default memory limit, in case prefs aren't available
mTotalSize(0),
mInactiveSize(0),
mEntryCount(0),
mMaxEntryCount(0)
{
PR_INIT_CLIST(&mEvictionList[mostLikelyToEvict]);
PR_INIT_CLIST(&mEvictionList[leastLikelyToEvict]);
}
nsMemoryCacheDevice::~nsMemoryCacheDevice()
{
Shutdown();
}
nsresult
nsMemoryCacheDevice::Init()
{
nsresult rv;
rv = mMemCacheEntries.Init();
// set some default memory limits, in case prefs aren't available
mSoftLimit = mHardLimit * 0.9;
// XXX Register as a memory pressure observer
return rv;
}
nsresult
nsMemoryCacheDevice::Shutdown()
{
mMemCacheEntries.Shutdown();
// evict all entries
nsCacheEntry * entry, * next;
for (int i=mostLikelyToEvict; i <= leastLikelyToEvict; ++i) {
entry = (nsCacheEntry *)PR_LIST_HEAD(&mEvictionList[i]);
while (entry != &mEvictionList[i]) {
NS_ASSERTION(entry->IsInUse() == PR_FALSE, "### shutting down with active entries.\n");
next = (nsCacheEntry *)PR_NEXT_LINK(entry);
PR_REMOVE_AND_INIT_LINK(entry);
// update statistics
PRUint32 memoryRecovered = entry->Size();
mTotalSize -= memoryRecovered;
mInactiveSize -= memoryRecovered;
--mEntryCount;
delete entry;
entry = next;
}
}
/*
* we're not factoring in changes to meta data yet...
* NS_ASSERTION(mTotalSize == 0, "### mem cache leaking entries?\n");
*/
NS_ASSERTION(mInactiveSize == 0, "### mem cache leaking entries?\n");
NS_ASSERTION(mEntryCount == 0, "### mem cache leaking entries?\n");
return NS_OK;
}
const char *
nsMemoryCacheDevice::GetDeviceID()
{
return gMemoryDeviceID;
}
nsCacheEntry *
nsMemoryCacheDevice::FindEntry(nsCString * key)
{
nsCacheEntry * entry = mMemCacheEntries.GetEntry(key);
if (!entry) return nsnull;
// move entry to the tail of an eviction list
PR_REMOVE_AND_INIT_LINK(entry);
PR_APPEND_LINK(entry, &mEvictionList[EvictionList(entry, 0)]);
mInactiveSize -= entry->Size();
return entry;
}
nsresult
nsMemoryCacheDevice::DeactivateEntry(nsCacheEntry * entry)
{
if (entry->IsDoomed()) {
#if debug
// XXX verify we've removed it from mMemCacheEntries & eviction list
#endif
// update statistics
mTotalSize -= entry->Size();
--mEntryCount;
delete entry;
return NS_OK;
}
nsCacheEntry * ourEntry = mMemCacheEntries.GetEntry(entry->Key());
NS_ASSERTION(ourEntry, "DeactivateEntry called for an entry we don't have!");
NS_ASSERTION(entry == ourEntry, "entry doesn't match ourEntry");
if (ourEntry != entry)
return NS_ERROR_INVALID_POINTER;
mInactiveSize += entry->Size();
EvictEntriesIfNecessary();
return NS_OK;
}
nsresult
nsMemoryCacheDevice::BindEntry(nsCacheEntry * entry)
{
if (!entry->IsDoomed()) {
NS_ASSERTION(PR_CLIST_IS_EMPTY(entry),"entry is already on a list!");
// append entry to the eviction list
PR_APPEND_LINK(entry, &mEvictionList[EvictionList(entry, 0)]);
// add entry to hashtable of mem cache entries
nsresult rv = mMemCacheEntries.AddEntry(entry);
if (NS_FAILED(rv)) {
PR_REMOVE_AND_INIT_LINK(entry);
return rv;
}
}
// add size of entry to memory totals
++mEntryCount;
if (mMaxEntryCount < mEntryCount) mMaxEntryCount = mEntryCount;
mTotalSize += entry->Size();
EvictEntriesIfNecessary();
return NS_OK;
}
void
nsMemoryCacheDevice::DoomEntry(nsCacheEntry * entry)
{
// XXX debug code to verify we have entry
mMemCacheEntries.RemoveEntry(entry);
// remove entry from our eviction list
PR_REMOVE_AND_INIT_LINK(entry);
}
nsresult
nsMemoryCacheDevice::GetTransportForEntry( nsCacheEntry * entry,
nsCacheAccessMode mode,
nsITransport ** transport )
{
NS_ENSURE_ARG_POINTER(entry);
NS_ENSURE_ARG_POINTER(transport);
nsCOMPtr<nsISupports> data;
nsresult rv = entry->GetData(getter_AddRefs(data));
if (NS_FAILED(rv))
return rv;
if (data)
return CallQueryInterface(data, transport);
else {
// create a new transport for this entry
rv = nsComponentManager::CreateInstance(kStorageTransportCID,
nsnull,
NS_GET_IID(nsITransport),
(void **) transport);
if (NS_FAILED(rv)) return rv;
entry->SetData(*transport);
return NS_OK;
}
}
nsresult
nsMemoryCacheDevice::GetFileForEntry( nsCacheEntry * entry,
nsIFile ** result )
{
return NS_ERROR_NOT_IMPLEMENTED;
}
nsresult
nsMemoryCacheDevice::OnDataSizeChange( nsCacheEntry * entry, PRInt32 deltaSize)
{
if (entry->IsStreamData()) {
// we have the right to refuse or pre-evict
}
// adjust our totals
mTotalSize += deltaSize;
if (!entry->IsDoomed()) {
// move entry to the tail of the appropriate eviction list
PR_REMOVE_AND_INIT_LINK(entry);
PR_APPEND_LINK(entry, &mEvictionList[EvictionList(entry, deltaSize)]);
}
EvictEntriesIfNecessary();
return NS_OK;
}
void
nsMemoryCacheDevice::AdjustMemoryLimits(PRUint32 softLimit, PRUint32 hardLimit)
{
mSoftLimit = softLimit;
mHardLimit = hardLimit;
EvictEntriesIfNecessary();
}
void
nsMemoryCacheDevice::EvictEntry(nsCacheEntry * entry)
{
// remove entry from our hashtable
mMemCacheEntries.RemoveEntry(entry);
// remove entry from the eviction list
PR_REMOVE_AND_INIT_LINK(entry);
// update statistics
PRUint32 memoryRecovered = entry->Size();
mTotalSize -= memoryRecovered;
mInactiveSize -= memoryRecovered;
--mEntryCount;
delete entry;
}
void
nsMemoryCacheDevice::EvictEntriesIfNecessary(void)
{
nsCacheEntry * entry, * next;
if ((mTotalSize < mHardLimit) && (mInactiveSize < mSoftLimit))
return;
for (int i=mostLikelyToEvict; i<=leastLikelyToEvict; ++i) {
entry = (nsCacheEntry *)PR_LIST_HEAD(&mEvictionList[i]);
while (entry != &mEvictionList[i]) {
if (entry->IsInUse()) {
entry = (nsCacheEntry *)PR_NEXT_LINK(entry);
continue;
}
next = (nsCacheEntry *)PR_NEXT_LINK(entry);
EvictEntry(entry);
entry = next;
if ((mTotalSize < mHardLimit) && (mInactiveSize < mSoftLimit))
return;
}
}
}
int
nsMemoryCacheDevice::EvictionList(nsCacheEntry * entry, PRUint32 deltaSize)
{
PRUint32 size = entry->Size() + deltaSize;
if ((size > mEvictionThreshold) || (entry->ExpirationTime() != 0))
return mostLikelyToEvict;
return leastLikelyToEvict;
}
nsresult
nsMemoryCacheDevice::Visit(nsICacheVisitor * visitor)
{
nsMemoryCacheDeviceInfo * deviceInfo = new nsMemoryCacheDeviceInfo(this);
nsCOMPtr<nsICacheDeviceInfo> deviceRef(deviceInfo);
if (!deviceInfo) return NS_ERROR_OUT_OF_MEMORY;
PRBool keepGoing;
nsresult rv = visitor->VisitDevice(gMemoryDeviceID, deviceInfo, &keepGoing);
if (NS_FAILED(rv)) return rv;
if (!keepGoing)
return NS_OK;
nsCacheEntry * entry;
nsCOMPtr<nsICacheEntryInfo> entryRef;
for (int i=mostLikelyToEvict; i <= leastLikelyToEvict; ++i) {
entry = (nsCacheEntry *)PR_LIST_HEAD(&mEvictionList[i]);
while (entry != &mEvictionList[i]) {
nsCacheEntryInfo * entryInfo = new nsCacheEntryInfo(entry);
if (!entryInfo) return NS_ERROR_OUT_OF_MEMORY;
entryRef = entryInfo;
rv = visitor->VisitEntry(gMemoryDeviceID, entryInfo, &keepGoing);
entryInfo->DetachEntry();
if (NS_FAILED(rv)) return rv;
if (!keepGoing) break;
entry = (nsCacheEntry *)PR_NEXT_LINK(entry);
}
}
return NS_OK;
}
nsresult
nsMemoryCacheDevice::EvictEntries(const char * clientID)
{
nsCacheEntry * entry;
PRUint32 prefixLength = (clientID ? nsCRT::strlen(clientID) : 0);
for (int i=mostLikelyToEvict; i<=leastLikelyToEvict; ++i) {
PRCList * elem = PR_LIST_HEAD(&mEvictionList[i]);
while (elem != &mEvictionList[i]) {
entry = (nsCacheEntry *)elem;
elem = PR_NEXT_LINK(elem);
const char * key = entry->Key()->get();
if (clientID && nsCRT::strncmp(clientID, key, prefixLength) != 0)
continue;
if (entry->IsInUse()) {
nsresult rv = nsCacheService::GlobalInstance()->DoomEntry_Locked(entry);
if (NS_FAILED(rv)) return rv;
} else {
EvictEntry(entry);
}
}
}
return NS_OK;
}
void
nsMemoryCacheDevice::SetCapacity(PRUint32 capacity)
{
PRUint32 hardLimit = capacity * 1024; // convert k into bytes
PRUint32 softLimit = hardLimit * 0.9;
AdjustMemoryLimits(softLimit, hardLimit);
}
/******************************************************************************
* nsMemoryCacheDeviceInfo - for implementing about:cache
*****************************************************************************/
NS_IMPL_ISUPPORTS1(nsMemoryCacheDeviceInfo, nsICacheDeviceInfo);
NS_IMETHODIMP
nsMemoryCacheDeviceInfo::GetDescription(char ** result)
{
NS_ENSURE_ARG_POINTER(result);
*result = nsCRT::strdup("Memory cache device");
if (!*result) return NS_ERROR_OUT_OF_MEMORY;
return NS_OK;
}
NS_IMETHODIMP
nsMemoryCacheDeviceInfo::GetUsageReport(char ** result)
{
NS_ENSURE_ARG_POINTER(result);
*result = nsCRT::strdup("Memory cache usage report:");
if (!*result) return NS_ERROR_OUT_OF_MEMORY;
return NS_OK;
}
NS_IMETHODIMP
nsMemoryCacheDeviceInfo::GetEntryCount(PRUint32 * result)
{
NS_ENSURE_ARG_POINTER(result);
// XXX compare calculated count vs. mEntryCount
*result = mDevice->mEntryCount;
return NS_OK;
}
NS_IMETHODIMP
nsMemoryCacheDeviceInfo::GetTotalSize(PRUint32 * result)
{
NS_ENSURE_ARG_POINTER(result);
*result = mDevice->mTotalSize;
return NS_OK;
}
NS_IMETHODIMP
nsMemoryCacheDeviceInfo::GetMaximumSize(PRUint32 * result)
{
NS_ENSURE_ARG_POINTER(result);
*result = mDevice->mHardLimit;
return NS_OK;
}