diff options
Diffstat (limited to 'src/ports/SkImageRef_ashmem.cpp')
| -rw-r--r-- | src/ports/SkImageRef_ashmem.cpp | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/src/ports/SkImageRef_ashmem.cpp b/src/ports/SkImageRef_ashmem.cpp new file mode 100644 index 0000000..a904bae --- /dev/null +++ b/src/ports/SkImageRef_ashmem.cpp @@ -0,0 +1,203 @@ +#include "SkImageRef_ashmem.h" +#include "SkImageDecoder.h" +#include "SkThread.h" + +#include <sys/mman.h> +#include <unistd.h> +#include <cutils/ashmem.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() { + fCT->safeUnref(); + 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 %d\n", + fd, err, errno); + 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 err=%d\n", + size, errno); + 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, treating as error %d\n", + fRec.fFD, pin, errno); + // 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); +} + |