blob: a4058ff6d77b0d42581194c9bdfa89989788655a [file] [log] [blame]
/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkImageRef_ashmem.h"
#include "SkImageDecoder.h"
#include "SkFlattenableBuffers.h"
#include "SkThread.h"
#include "android/ashmem.h"
#include <sys/mman.h>
#include <unistd.h>
//#define TRACE_ASH_PURGE // just trace purges
#ifdef DUMP_IMAGEREF_LIFECYCLE
#define DUMP_ASHMEM_LIFECYCLE
#else
// #define DUMP_ASHMEM_LIFECYCLE
#endif
// ashmem likes lengths on page boundaries
static size_t roundToPageSize(size_t size) {
const size_t mask = getpagesize() - 1;
size_t newsize = (size + mask) & ~mask;
// SkDebugf("---- oldsize %d newsize %d\n", size, newsize);
return newsize;
}
SkImageRef_ashmem::SkImageRef_ashmem(SkStream* stream,
SkBitmap::Config config,
int sampleSize)
: SkImageRef(stream, config, sampleSize) {
fRec.fFD = -1;
fRec.fAddr = NULL;
fRec.fSize = 0;
fRec.fPinned = false;
fCT = NULL;
}
SkImageRef_ashmem::~SkImageRef_ashmem() {
SkSafeUnref(fCT);
this->closeFD();
}
void SkImageRef_ashmem::closeFD() {
if (-1 != fRec.fFD) {
#ifdef DUMP_ASHMEM_LIFECYCLE
SkDebugf("=== ashmem close %d\n", fRec.fFD);
#endif
SkASSERT(fRec.fAddr);
SkASSERT(fRec.fSize);
munmap(fRec.fAddr, fRec.fSize);
close(fRec.fFD);
fRec.fFD = -1;
}
}
///////////////////////////////////////////////////////////////////////////////
class AshmemAllocator : public SkBitmap::Allocator {
public:
AshmemAllocator(SkAshmemRec* rec, const char name[])
: fRec(rec), fName(name) {}
virtual bool allocPixelRef(SkBitmap* bm, SkColorTable* ct) {
const size_t size = roundToPageSize(bm->getSize());
int fd = fRec->fFD;
void* addr = fRec->fAddr;
SkASSERT(!fRec->fPinned);
if (-1 == fd) {
SkASSERT(NULL == addr);
SkASSERT(0 == fRec->fSize);
fd = ashmem_create_region(fName, size);
#ifdef DUMP_ASHMEM_LIFECYCLE
SkDebugf("=== ashmem_create_region %s size=%d fd=%d\n", fName, size, fd);
#endif
if (-1 == fd) {
SkDebugf("------- imageref_ashmem create failed <%s> %d\n",
fName, size);
return false;
}
int err = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE);
if (err) {
SkDebugf("------ ashmem_set_prot_region(%d) failed %d\n",
fd, err);
close(fd);
return false;
}
addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
if (-1 == (long)addr) {
SkDebugf("---------- mmap failed for imageref_ashmem size=%d\n",
size);
close(fd);
return false;
}
fRec->fFD = fd;
fRec->fAddr = addr;
fRec->fSize = size;
} else {
SkASSERT(addr);
SkASSERT(size == fRec->fSize);
(void)ashmem_pin_region(fd, 0, 0);
}
bm->setPixels(addr, ct);
fRec->fPinned = true;
return true;
}
private:
// we just point to our caller's memory, these are not copies
SkAshmemRec* fRec;
const char* fName;
};
bool SkImageRef_ashmem::onDecode(SkImageDecoder* codec, SkStream* stream,
SkBitmap* bitmap, SkBitmap::Config config,
SkImageDecoder::Mode mode) {
if (SkImageDecoder::kDecodeBounds_Mode == mode) {
return this->INHERITED::onDecode(codec, stream, bitmap, config, mode);
}
AshmemAllocator alloc(&fRec, this->getURI());
codec->setAllocator(&alloc);
bool success = this->INHERITED::onDecode(codec, stream, bitmap, config,
mode);
// remove the allocator, since its on the stack
codec->setAllocator(NULL);
if (success) {
// remember the colortable (if any)
SkRefCnt_SafeAssign(fCT, bitmap->getColorTable());
return true;
} else {
if (fRec.fPinned) {
ashmem_unpin_region(fRec.fFD, 0, 0);
fRec.fPinned = false;
}
this->closeFD();
return false;
}
}
void* SkImageRef_ashmem::onLockPixels(SkColorTable** ct) {
SkASSERT(fBitmap.getPixels() == NULL);
SkASSERT(fBitmap.getColorTable() == NULL);
// fast case: check if we can just pin and get the cached data
if (-1 != fRec.fFD) {
SkASSERT(fRec.fAddr);
SkASSERT(!fRec.fPinned);
int pin = ashmem_pin_region(fRec.fFD, 0, 0);
if (ASHMEM_NOT_PURGED == pin) { // yea, fast case!
fBitmap.setPixels(fRec.fAddr, fCT);
fRec.fPinned = true;
} else if (ASHMEM_WAS_PURGED == pin) {
ashmem_unpin_region(fRec.fFD, 0, 0);
// let go of our colortable if we lost the pixels. Well get it back
// again when we re-decode
if (fCT) {
fCT->unref();
fCT = NULL;
}
#if defined(DUMP_ASHMEM_LIFECYCLE) || defined(TRACE_ASH_PURGE)
SkDebugf("===== ashmem purged %d\n", fBitmap.getSize());
#endif
} else {
SkDebugf("===== ashmem pin_region(%d) returned %d\n", fRec.fFD, pin);
// return null result for failure
if (ct) {
*ct = NULL;
}
return NULL;
}
} else {
// no FD, will create an ashmem region in allocator
}
return this->INHERITED::onLockPixels(ct);
}
void SkImageRef_ashmem::onUnlockPixels() {
this->INHERITED::onUnlockPixels();
if (-1 != fRec.fFD) {
SkASSERT(fRec.fAddr);
SkASSERT(fRec.fPinned);
ashmem_unpin_region(fRec.fFD, 0, 0);
fRec.fPinned = false;
}
// we clear this with or without an error, since we've either closed or
// unpinned the region
fBitmap.setPixels(NULL, NULL);
}
void SkImageRef_ashmem::flatten(SkFlattenableWriteBuffer& buffer) const {
this->INHERITED::flatten(buffer);
buffer.writeString(getURI());
}
SkImageRef_ashmem::SkImageRef_ashmem(SkFlattenableReadBuffer& buffer)
: INHERITED(buffer) {
fRec.fFD = -1;
fRec.fAddr = NULL;
fRec.fSize = 0;
fRec.fPinned = false;
fCT = NULL;
SkString uri;
buffer.readString(&uri);
this->setURI(uri);
}