/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
+ * are subject to the Apple Public Source License Version 2.0 (the
* "License"). You may not use this file except in compliance with the
* License. Please obtain a copy of the License at
* http://www.apple.com/publicsource and read it before using this file.
static char gCacheBuffer[kCacheSize];
#endif
+#if CACHE_STATS
unsigned long gCacheHits;
unsigned long gCacheMisses;
unsigned long gCacheEvicts;
+#endif
void CacheInit( CICell ih, long blockSize )
{
gCacheNumEntries = kCacheSize / gCacheBlockSize;
gCacheTime = 0;
+#if CACHE_STATS
gCacheHits = 0;
gCacheMisses = 0;
gCacheEvicts = 0;
+#endif
gCacheIH = ih;
long CacheRead( CICell ih, char * buffer, long long offset,
long length, long cache )
{
- long cnt, oldestEntry = 0, oldestTime, loadCache = 0;
- CacheEntry *entry;
+ long cnt, oldestEntry = 0, oldestTime, loadCache = 0;
+ CacheEntry *entry;
// See if the data can be cached.
if (cache && (gCacheIH == ih) && (length == gCacheBlockSize)) {
// If the data was found copy it to the caller.
if (cnt != gCacheNumEntries) {
bcopy(gCacheBuffer + cnt * gCacheBlockSize, buffer, gCacheBlockSize);
+#if CACHE_STATS
gCacheHits++;
+#endif
return gCacheBlockSize;
}
// Read the data from the disk.
Seek(ih, offset);
Read(ih, (long)buffer, length);
+#if CACHE_STATS
if (cache) gCacheMisses++;
+#endif
// Put the data from the disk in the cache if needed.
if (loadCache) {
// If no free entry was found, use the oldest.
if (cnt == gCacheNumEntries) {
cnt = oldestEntry;
+#if CACHE_STATS
gCacheEvicts++;
+#endif
}
// Copy the data from disk to the new entry.