grab from latest android
git-svn-id: http://skia.googlecode.com/svn/trunk@27 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/images/SkImageRefPool.cpp b/src/images/SkImageRefPool.cpp
new file mode 100644
index 0000000..e322507
--- /dev/null
+++ b/src/images/SkImageRefPool.cpp
@@ -0,0 +1,186 @@
+#include "SkImageRefPool.h"
+#include "SkImageRef.h"
+#include "SkThread.h"
+
+SkImageRefPool::SkImageRefPool() {
+ fRAMBudget = 0; // means no explicit limit
+ fRAMUsed = 0;
+ fCount = 0;
+ fHead = fTail = NULL;
+}
+
+SkImageRefPool::~SkImageRefPool() {
+ // SkASSERT(NULL == fHead);
+}
+
+void SkImageRefPool::setRAMBudget(size_t size) {
+ if (fRAMBudget != size) {
+ fRAMBudget = size;
+ this->purgeIfNeeded();
+ }
+}
+
+void SkImageRefPool::justAddedPixels(SkImageRef* ref) {
+#ifdef DUMP_IMAGEREF_LIFECYCLE
+ SkDebugf("=== ImagePool: add pixels %s [%d %d %d] bytes=%d heap=%d\n",
+ ref->getURI(),
+ ref->fBitmap.width(), ref->fBitmap.height(),
+ ref->fBitmap.bytesPerPixel(),
+ ref->fBitmap.getSize(), (int)fRAMUsed);
+#endif
+ fRAMUsed += ref->ramUsed();
+ this->purgeIfNeeded();
+}
+
+void SkImageRefPool::canLosePixels(SkImageRef* ref) {
+ // the refs near fHead have recently been released (used)
+ // if we purge, we purge from the tail
+ this->detach(ref);
+ this->addToHead(ref);
+ this->purgeIfNeeded();
+}
+
+void SkImageRefPool::purgeIfNeeded() {
+ // do nothing if we have a zero-budget (i.e. unlimited)
+ if (fRAMBudget != 0) {
+ this->setRAMUsed(fRAMBudget);
+ }
+}
+
+void SkImageRefPool::setRAMUsed(size_t limit) {
+ SkImageRef* ref = fTail;
+
+ while (NULL != ref && fRAMUsed > limit) {
+ // only purge it if its pixels are unlocked
+ if (0 == ref->getLockCount() && ref->fBitmap.getPixels()) {
+ size_t size = ref->ramUsed();
+ SkASSERT(size <= fRAMUsed);
+ fRAMUsed -= size;
+
+#ifdef DUMP_IMAGEREF_LIFECYCLE
+ SkDebugf("=== ImagePool: purge %s [%d %d %d] bytes=%d heap=%d\n",
+ ref->getURI(),
+ ref->fBitmap.width(), ref->fBitmap.height(),
+ ref->fBitmap.bytesPerPixel(),
+ (int)size, (int)fRAMUsed);
+#endif
+
+ // remember the bitmap config (don't call reset),
+ // just clear the pixel memory
+ ref->fBitmap.setPixels(NULL);
+ SkASSERT(NULL == ref->fBitmap.getPixels());
+ }
+ ref = ref->fPrev;
+ }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkImageRefPool::addToHead(SkImageRef* ref) {
+ ref->fNext = fHead;
+ ref->fPrev = NULL;
+
+ if (fHead) {
+ SkASSERT(NULL == fHead->fPrev);
+ fHead->fPrev = ref;
+ }
+ fHead = ref;
+
+ if (NULL == fTail) {
+ fTail = ref;
+ }
+ fCount += 1;
+ SkASSERT(computeCount() == fCount);
+
+ fRAMUsed += ref->ramUsed();
+}
+
+void SkImageRefPool::addToTail(SkImageRef* ref) {
+ ref->fNext = NULL;
+ ref->fPrev = fTail;
+
+ if (fTail) {
+ SkASSERT(NULL == fTail->fNext);
+ fTail->fNext = ref;
+ }
+ fTail = ref;
+
+ if (NULL == fHead) {
+ fHead = ref;
+ }
+ fCount += 1;
+ SkASSERT(computeCount() == fCount);
+
+ fRAMUsed += ref->ramUsed();
+}
+
+void SkImageRefPool::detach(SkImageRef* ref) {
+ SkASSERT(fCount > 0);
+
+ if (fHead == ref) {
+ fHead = ref->fNext;
+ }
+ if (fTail == ref) {
+ fTail = ref->fPrev;
+ }
+ if (ref->fPrev) {
+ ref->fPrev->fNext = ref->fNext;
+ }
+ if (ref->fNext) {
+ ref->fNext->fPrev = ref->fPrev;
+ }
+
+ ref->fNext = ref->fPrev = NULL;
+
+ fCount -= 1;
+ SkASSERT(computeCount() == fCount);
+
+ SkASSERT(fRAMUsed >= ref->ramUsed());
+ fRAMUsed -= ref->ramUsed();
+}
+
+int SkImageRefPool::computeCount() const {
+ SkImageRef* ref = fHead;
+ int count = 0;
+
+ while (ref != NULL) {
+ count += 1;
+ ref = ref->fNext;
+ }
+
+#ifdef SK_DEBUG
+ ref = fTail;
+ int count2 = 0;
+
+ while (ref != NULL) {
+ count2 += 1;
+ ref = ref->fPrev;
+ }
+ SkASSERT(count2 == count);
+#endif
+
+ return count;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+#include "SkStream.h"
+
+void SkImageRefPool::dump() const {
+#if defined(SK_DEBUG) || defined(DUMP_IMAGEREF_LIFECYCLE)
+ SkDebugf("ImagePool dump: bugdet: %d used: %d count: %d\n",
+ (int)fRAMBudget, (int)fRAMUsed, fCount);
+
+ SkImageRef* ref = fHead;
+
+ while (ref != NULL) {
+ SkDebugf(" [%3d %3d %d] ram=%d data=%d locks=%d %s\n", ref->fBitmap.width(),
+ ref->fBitmap.height(), ref->fBitmap.config(),
+ ref->ramUsed(), (int)ref->fStream->getLength(),
+ ref->getLockCount(), ref->getURI());
+
+ ref = ref->fNext;
+ }
+#endif
+}
+