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      1 #define LOG_TAG "BitmapFactory"
      2 
      3 #include "BitmapFactory.h"
      4 #include "NinePatchPeeker.h"
      5 #include "SkData.h"
      6 #include "SkFrontBufferedStream.h"
      7 #include "SkImageDecoder.h"
      8 #include "SkImageRef_ashmem.h"
      9 #include "SkImageRef_GlobalPool.h"
     10 #include "SkPixelRef.h"
     11 #include "SkStream.h"
     12 #include "SkTemplates.h"
     13 #include "SkUtils.h"
     14 #include "CreateJavaOutputStreamAdaptor.h"
     15 #include "AutoDecodeCancel.h"
     16 #include "Utils.h"
     17 #include "JNIHelp.h"
     18 #include "GraphicsJNI.h"
     19 
     20 #include <android_runtime/AndroidRuntime.h>
     21 #include <androidfw/Asset.h>
     22 #include <androidfw/ResourceTypes.h>
     23 #include <netinet/in.h>
     24 #include <sys/mman.h>
     25 #include <sys/stat.h>
     26 
     27 jfieldID gOptions_justBoundsFieldID;
     28 jfieldID gOptions_sampleSizeFieldID;
     29 jfieldID gOptions_configFieldID;
     30 jfieldID gOptions_premultipliedFieldID;
     31 jfieldID gOptions_mutableFieldID;
     32 jfieldID gOptions_ditherFieldID;
     33 jfieldID gOptions_purgeableFieldID;
     34 jfieldID gOptions_shareableFieldID;
     35 jfieldID gOptions_preferQualityOverSpeedFieldID;
     36 jfieldID gOptions_scaledFieldID;
     37 jfieldID gOptions_densityFieldID;
     38 jfieldID gOptions_screenDensityFieldID;
     39 jfieldID gOptions_targetDensityFieldID;
     40 jfieldID gOptions_widthFieldID;
     41 jfieldID gOptions_heightFieldID;
     42 jfieldID gOptions_mimeFieldID;
     43 jfieldID gOptions_mCancelID;
     44 jfieldID gOptions_bitmapFieldID;
     45 jfieldID gBitmap_nativeBitmapFieldID;
     46 jfieldID gBitmap_layoutBoundsFieldID;
     47 
     48 #if 0
     49     #define TRACE_BITMAP(code)  code
     50 #else
     51     #define TRACE_BITMAP(code)
     52 #endif
     53 
     54 using namespace android;
     55 
     56 static inline int32_t validOrNeg1(bool isValid, int32_t value) {
     57 //    return isValid ? value : -1;
     58     SkASSERT((int)isValid == 0 || (int)isValid == 1);
     59     return ((int32_t)isValid - 1) | value;
     60 }
     61 
     62 jstring getMimeTypeString(JNIEnv* env, SkImageDecoder::Format format) {
     63     static const struct {
     64         SkImageDecoder::Format fFormat;
     65         const char*            fMimeType;
     66     } gMimeTypes[] = {
     67         { SkImageDecoder::kBMP_Format,  "image/bmp" },
     68         { SkImageDecoder::kGIF_Format,  "image/gif" },
     69         { SkImageDecoder::kICO_Format,  "image/x-ico" },
     70         { SkImageDecoder::kJPEG_Format, "image/jpeg" },
     71         { SkImageDecoder::kPNG_Format,  "image/png" },
     72         { SkImageDecoder::kWEBP_Format, "image/webp" },
     73         { SkImageDecoder::kWBMP_Format, "image/vnd.wap.wbmp" }
     74     };
     75 
     76     const char* cstr = NULL;
     77     for (size_t i = 0; i < SK_ARRAY_COUNT(gMimeTypes); i++) {
     78         if (gMimeTypes[i].fFormat == format) {
     79             cstr = gMimeTypes[i].fMimeType;
     80             break;
     81         }
     82     }
     83 
     84     jstring jstr = 0;
     85     if (NULL != cstr) {
     86         jstr = env->NewStringUTF(cstr);
     87     }
     88     return jstr;
     89 }
     90 
     91 static bool optionsPurgeable(JNIEnv* env, jobject options) {
     92     return options != NULL && env->GetBooleanField(options, gOptions_purgeableFieldID);
     93 }
     94 
     95 static bool optionsShareable(JNIEnv* env, jobject options) {
     96     return options != NULL && env->GetBooleanField(options, gOptions_shareableFieldID);
     97 }
     98 
     99 static bool optionsJustBounds(JNIEnv* env, jobject options) {
    100     return options != NULL && env->GetBooleanField(options, gOptions_justBoundsFieldID);
    101 }
    102 
    103 static void scaleNinePatchChunk(android::Res_png_9patch* chunk, float scale) {
    104     chunk->paddingLeft = int(chunk->paddingLeft * scale + 0.5f);
    105     chunk->paddingTop = int(chunk->paddingTop * scale + 0.5f);
    106     chunk->paddingRight = int(chunk->paddingRight * scale + 0.5f);
    107     chunk->paddingBottom = int(chunk->paddingBottom * scale + 0.5f);
    108 
    109     for (int i = 0; i < chunk->numXDivs; i++) {
    110         chunk->xDivs[i] = int(chunk->xDivs[i] * scale + 0.5f);
    111         if (i > 0 && chunk->xDivs[i] == chunk->xDivs[i - 1]) {
    112             chunk->xDivs[i]++;
    113         }
    114     }
    115 
    116     for (int i = 0; i < chunk->numYDivs; i++) {
    117         chunk->yDivs[i] = int(chunk->yDivs[i] * scale + 0.5f);
    118         if (i > 0 && chunk->yDivs[i] == chunk->yDivs[i - 1]) {
    119             chunk->yDivs[i]++;
    120         }
    121     }
    122 }
    123 
    124 static SkPixelRef* installPixelRef(SkBitmap* bitmap, SkStreamRewindable* stream,
    125         int sampleSize, bool ditherImage) {
    126 
    127     SkImageRef* pr;
    128     // only use ashmem for large images, since mmaps come at a price
    129     if (bitmap->getSize() >= 32 * 1024) {
    130         pr = new SkImageRef_ashmem(stream, bitmap->config(), sampleSize);
    131     } else {
    132         pr = new SkImageRef_GlobalPool(stream, bitmap->config(), sampleSize);
    133     }
    134     pr->setDitherImage(ditherImage);
    135     bitmap->setPixelRef(pr)->unref();
    136     pr->isOpaque(bitmap);
    137     return pr;
    138 }
    139 
    140 static SkBitmap::Config configForScaledOutput(SkBitmap::Config config) {
    141     switch (config) {
    142         case SkBitmap::kNo_Config:
    143         case SkBitmap::kIndex8_Config:
    144             return SkBitmap::kARGB_8888_Config;
    145         default:
    146             break;
    147     }
    148     return config;
    149 }
    150 
    151 class ScaleCheckingAllocator : public SkBitmap::HeapAllocator {
    152 public:
    153     ScaleCheckingAllocator(float scale, int size)
    154             : mScale(scale), mSize(size) {
    155     }
    156 
    157     virtual bool allocPixelRef(SkBitmap* bitmap, SkColorTable* ctable) {
    158         // accounts for scale in final allocation, using eventual size and config
    159         const int bytesPerPixel = SkBitmap::ComputeBytesPerPixel(
    160                 configForScaledOutput(bitmap->getConfig()));
    161         const int requestedSize = bytesPerPixel *
    162                 int(bitmap->width() * mScale + 0.5f) *
    163                 int(bitmap->height() * mScale + 0.5f);
    164         if (requestedSize > mSize) {
    165             ALOGW("bitmap for alloc reuse (%d bytes) can't fit scaled bitmap (%d bytes)",
    166                     mSize, requestedSize);
    167             return false;
    168         }
    169         return SkBitmap::HeapAllocator::allocPixelRef(bitmap, ctable);
    170     }
    171 private:
    172     const float mScale;
    173     const int mSize;
    174 };
    175 
    176 class RecyclingPixelAllocator : public SkBitmap::Allocator {
    177 public:
    178     RecyclingPixelAllocator(SkPixelRef* pixelRef, unsigned int size)
    179             : mPixelRef(pixelRef), mSize(size) {
    180         SkSafeRef(mPixelRef);
    181     }
    182 
    183     ~RecyclingPixelAllocator() {
    184         SkSafeUnref(mPixelRef);
    185     }
    186 
    187     virtual bool allocPixelRef(SkBitmap* bitmap, SkColorTable* ctable) {
    188         if (!bitmap->getSize64().is32() || bitmap->getSize() > mSize) {
    189             ALOGW("bitmap marked for reuse (%d bytes) can't fit new bitmap (%d bytes)",
    190                     mSize, bitmap->getSize());
    191             return false;
    192         }
    193 
    194         // Create a new pixelref with the new ctable that wraps the previous pixelref
    195         SkPixelRef* pr = new AndroidPixelRef(*static_cast<AndroidPixelRef*>(mPixelRef), ctable);
    196 
    197         bitmap->setPixelRef(pr)->unref();
    198         // since we're already allocated, we lockPixels right away
    199         // HeapAllocator/JavaPixelAllocator behaves this way too
    200         bitmap->lockPixels();
    201         return true;
    202     }
    203 
    204 private:
    205     SkPixelRef* const mPixelRef;
    206     const unsigned int mSize;
    207 };
    208 
    209 // since we "may" create a purgeable imageref, we require the stream be ref'able
    210 // i.e. dynamically allocated, since its lifetime may exceed the current stack
    211 // frame.
    212 static jobject doDecode(JNIEnv* env, SkStreamRewindable* stream, jobject padding,
    213         jobject options, bool allowPurgeable, bool forcePurgeable = false) {
    214 
    215     int sampleSize = 1;
    216 
    217     SkImageDecoder::Mode mode = SkImageDecoder::kDecodePixels_Mode;
    218     SkBitmap::Config prefConfig = SkBitmap::kARGB_8888_Config;
    219 
    220     bool doDither = true;
    221     bool isMutable = false;
    222     float scale = 1.0f;
    223     bool isPurgeable = forcePurgeable || (allowPurgeable && optionsPurgeable(env, options));
    224     bool preferQualityOverSpeed = false;
    225     bool requireUnpremultiplied = false;
    226 
    227     jobject javaBitmap = NULL;
    228 
    229     if (options != NULL) {
    230         sampleSize = env->GetIntField(options, gOptions_sampleSizeFieldID);
    231         if (optionsJustBounds(env, options)) {
    232             mode = SkImageDecoder::kDecodeBounds_Mode;
    233         }
    234 
    235         // initialize these, in case we fail later on
    236         env->SetIntField(options, gOptions_widthFieldID, -1);
    237         env->SetIntField(options, gOptions_heightFieldID, -1);
    238         env->SetObjectField(options, gOptions_mimeFieldID, 0);
    239 
    240         jobject jconfig = env->GetObjectField(options, gOptions_configFieldID);
    241         prefConfig = GraphicsJNI::getNativeBitmapConfig(env, jconfig);
    242         isMutable = env->GetBooleanField(options, gOptions_mutableFieldID);
    243         doDither = env->GetBooleanField(options, gOptions_ditherFieldID);
    244         preferQualityOverSpeed = env->GetBooleanField(options,
    245                 gOptions_preferQualityOverSpeedFieldID);
    246         requireUnpremultiplied = !env->GetBooleanField(options, gOptions_premultipliedFieldID);
    247         javaBitmap = env->GetObjectField(options, gOptions_bitmapFieldID);
    248 
    249         if (env->GetBooleanField(options, gOptions_scaledFieldID)) {
    250             const int density = env->GetIntField(options, gOptions_densityFieldID);
    251             const int targetDensity = env->GetIntField(options, gOptions_targetDensityFieldID);
    252             const int screenDensity = env->GetIntField(options, gOptions_screenDensityFieldID);
    253             if (density != 0 && targetDensity != 0 && density != screenDensity) {
    254                 scale = (float) targetDensity / density;
    255             }
    256         }
    257     }
    258 
    259     const bool willScale = scale != 1.0f;
    260     isPurgeable &= !willScale;
    261 
    262     SkImageDecoder* decoder = SkImageDecoder::Factory(stream);
    263     if (decoder == NULL) {
    264         return nullObjectReturn("SkImageDecoder::Factory returned null");
    265     }
    266 
    267     decoder->setSampleSize(sampleSize);
    268     decoder->setDitherImage(doDither);
    269     decoder->setPreferQualityOverSpeed(preferQualityOverSpeed);
    270     decoder->setRequireUnpremultipliedColors(requireUnpremultiplied);
    271 
    272     SkBitmap* outputBitmap = NULL;
    273     unsigned int existingBufferSize = 0;
    274     if (javaBitmap != NULL) {
    275         outputBitmap = (SkBitmap*) env->GetIntField(javaBitmap, gBitmap_nativeBitmapFieldID);
    276         if (outputBitmap->isImmutable()) {
    277             ALOGW("Unable to reuse an immutable bitmap as an image decoder target.");
    278             javaBitmap = NULL;
    279             outputBitmap = NULL;
    280         } else {
    281             existingBufferSize = GraphicsJNI::getBitmapAllocationByteCount(env, javaBitmap);
    282         }
    283     }
    284 
    285     SkAutoTDelete<SkBitmap> adb(outputBitmap == NULL ? new SkBitmap : NULL);
    286     if (outputBitmap == NULL) outputBitmap = adb.get();
    287 
    288     NinePatchPeeker peeker(decoder);
    289     decoder->setPeeker(&peeker);
    290 
    291     SkImageDecoder::Mode decodeMode = isPurgeable ? SkImageDecoder::kDecodeBounds_Mode : mode;
    292 
    293     JavaPixelAllocator javaAllocator(env);
    294     RecyclingPixelAllocator recyclingAllocator(outputBitmap->pixelRef(), existingBufferSize);
    295     ScaleCheckingAllocator scaleCheckingAllocator(scale, existingBufferSize);
    296     SkBitmap::Allocator* outputAllocator = (javaBitmap != NULL) ?
    297             (SkBitmap::Allocator*)&recyclingAllocator : (SkBitmap::Allocator*)&javaAllocator;
    298     if (decodeMode != SkImageDecoder::kDecodeBounds_Mode) {
    299         if (!willScale) {
    300             // If the java allocator is being used to allocate the pixel memory, the decoder
    301             // need not write zeroes, since the memory is initialized to 0.
    302             decoder->setSkipWritingZeroes(outputAllocator == &javaAllocator);
    303             decoder->setAllocator(outputAllocator);
    304         } else if (javaBitmap != NULL) {
    305             // check for eventual scaled bounds at allocation time, so we don't decode the bitmap
    306             // only to find the scaled result too large to fit in the allocation
    307             decoder->setAllocator(&scaleCheckingAllocator);
    308         }
    309     }
    310 
    311     // Only setup the decoder to be deleted after its stack-based, refcounted
    312     // components (allocators, peekers, etc) are declared. This prevents RefCnt
    313     // asserts from firing due to the order objects are deleted from the stack.
    314     SkAutoTDelete<SkImageDecoder> add(decoder);
    315 
    316     AutoDecoderCancel adc(options, decoder);
    317 
    318     // To fix the race condition in case "requestCancelDecode"
    319     // happens earlier than AutoDecoderCancel object is added
    320     // to the gAutoDecoderCancelMutex linked list.
    321     if (options != NULL && env->GetBooleanField(options, gOptions_mCancelID)) {
    322         return nullObjectReturn("gOptions_mCancelID");
    323     }
    324 
    325     SkBitmap decodingBitmap;
    326     if (!decoder->decode(stream, &decodingBitmap, prefConfig, decodeMode)) {
    327         return nullObjectReturn("decoder->decode returned false");
    328     }
    329 
    330     int scaledWidth = decodingBitmap.width();
    331     int scaledHeight = decodingBitmap.height();
    332 
    333     if (willScale && mode != SkImageDecoder::kDecodeBounds_Mode) {
    334         scaledWidth = int(scaledWidth * scale + 0.5f);
    335         scaledHeight = int(scaledHeight * scale + 0.5f);
    336     }
    337 
    338     // update options (if any)
    339     if (options != NULL) {
    340         env->SetIntField(options, gOptions_widthFieldID, scaledWidth);
    341         env->SetIntField(options, gOptions_heightFieldID, scaledHeight);
    342         env->SetObjectField(options, gOptions_mimeFieldID,
    343                 getMimeTypeString(env, decoder->getFormat()));
    344     }
    345 
    346     // if we're in justBounds mode, return now (skip the java bitmap)
    347     if (mode == SkImageDecoder::kDecodeBounds_Mode) {
    348         return NULL;
    349     }
    350 
    351     jbyteArray ninePatchChunk = NULL;
    352     if (peeker.fPatch != NULL) {
    353         if (willScale) {
    354             scaleNinePatchChunk(peeker.fPatch, scale);
    355         }
    356 
    357         size_t ninePatchArraySize = peeker.fPatch->serializedSize();
    358         ninePatchChunk = env->NewByteArray(ninePatchArraySize);
    359         if (ninePatchChunk == NULL) {
    360             return nullObjectReturn("ninePatchChunk == null");
    361         }
    362 
    363         jbyte* array = (jbyte*) env->GetPrimitiveArrayCritical(ninePatchChunk, NULL);
    364         if (array == NULL) {
    365             return nullObjectReturn("primitive array == null");
    366         }
    367 
    368         peeker.fPatch->serialize(array);
    369         env->ReleasePrimitiveArrayCritical(ninePatchChunk, array, 0);
    370     }
    371 
    372     jintArray layoutBounds = NULL;
    373     if (peeker.fLayoutBounds != NULL) {
    374         layoutBounds = env->NewIntArray(4);
    375         if (layoutBounds == NULL) {
    376             return nullObjectReturn("layoutBounds == null");
    377         }
    378 
    379         jint scaledBounds[4];
    380         if (willScale) {
    381             for (int i=0; i<4; i++) {
    382                 scaledBounds[i] = (jint)((((jint*)peeker.fLayoutBounds)[i]*scale) + .5f);
    383             }
    384         } else {
    385             memcpy(scaledBounds, (jint*)peeker.fLayoutBounds, sizeof(scaledBounds));
    386         }
    387         env->SetIntArrayRegion(layoutBounds, 0, 4, scaledBounds);
    388         if (javaBitmap != NULL) {
    389             env->SetObjectField(javaBitmap, gBitmap_layoutBoundsFieldID, layoutBounds);
    390         }
    391     }
    392 
    393     if (willScale) {
    394         // This is weird so let me explain: we could use the scale parameter
    395         // directly, but for historical reasons this is how the corresponding
    396         // Dalvik code has always behaved. We simply recreate the behavior here.
    397         // The result is slightly different from simply using scale because of
    398         // the 0.5f rounding bias applied when computing the target image size
    399         const float sx = scaledWidth / float(decodingBitmap.width());
    400         const float sy = scaledHeight / float(decodingBitmap.height());
    401 
    402         // TODO: avoid copying when scaled size equals decodingBitmap size
    403         SkBitmap::Config config = configForScaledOutput(decodingBitmap.config());
    404         outputBitmap->setConfig(config, scaledWidth, scaledHeight);
    405         outputBitmap->setIsOpaque(decodingBitmap.isOpaque());
    406         if (!outputBitmap->allocPixels(outputAllocator, NULL)) {
    407             return nullObjectReturn("allocation failed for scaled bitmap");
    408         }
    409 
    410         // If outputBitmap's pixels are newly allocated by Java, there is no need
    411         // to erase to 0, since the pixels were initialized to 0.
    412         if (outputAllocator != &javaAllocator) {
    413             outputBitmap->eraseColor(0);
    414         }
    415 
    416         SkPaint paint;
    417         paint.setFilterBitmap(true);
    418 
    419         SkCanvas canvas(*outputBitmap);
    420         canvas.scale(sx, sy);
    421         canvas.drawBitmap(decodingBitmap, 0.0f, 0.0f, &paint);
    422     } else {
    423         outputBitmap->swap(decodingBitmap);
    424     }
    425 
    426     if (padding) {
    427         if (peeker.fPatch != NULL) {
    428             GraphicsJNI::set_jrect(env, padding,
    429                     peeker.fPatch->paddingLeft, peeker.fPatch->paddingTop,
    430                     peeker.fPatch->paddingRight, peeker.fPatch->paddingBottom);
    431         } else {
    432             GraphicsJNI::set_jrect(env, padding, -1, -1, -1, -1);
    433         }
    434     }
    435 
    436     SkPixelRef* pr;
    437     if (isPurgeable) {
    438         pr = installPixelRef(outputBitmap, stream, sampleSize, doDither);
    439     } else {
    440         // if we get here, we're in kDecodePixels_Mode and will therefore
    441         // already have a pixelref installed.
    442         pr = outputBitmap->pixelRef();
    443     }
    444     if (pr == NULL) {
    445         return nullObjectReturn("Got null SkPixelRef");
    446     }
    447 
    448     if (!isMutable && javaBitmap == NULL) {
    449         // promise we will never change our pixels (great for sharing and pictures)
    450         pr->setImmutable();
    451     }
    452 
    453     // detach bitmap from its autodeleter, since we want to own it now
    454     adb.detach();
    455 
    456     if (javaBitmap != NULL) {
    457         bool isPremultiplied = !requireUnpremultiplied;
    458         GraphicsJNI::reinitBitmap(env, javaBitmap, outputBitmap, isPremultiplied);
    459         outputBitmap->notifyPixelsChanged();
    460         // If a java bitmap was passed in for reuse, pass it back
    461         return javaBitmap;
    462     }
    463 
    464     int bitmapCreateFlags = 0x0;
    465     if (isMutable) bitmapCreateFlags |= GraphicsJNI::kBitmapCreateFlag_Mutable;
    466     if (!requireUnpremultiplied) bitmapCreateFlags |= GraphicsJNI::kBitmapCreateFlag_Premultiplied;
    467 
    468     // now create the java bitmap
    469     return GraphicsJNI::createBitmap(env, outputBitmap, javaAllocator.getStorageObj(),
    470             bitmapCreateFlags, ninePatchChunk, layoutBounds, -1);
    471 }
    472 
    473 static jobject nativeDecodeStream(JNIEnv* env, jobject clazz, jobject is, jbyteArray storage,
    474         jobject padding, jobject options) {
    475 
    476     jobject bitmap = NULL;
    477     SkAutoTUnref<SkStream> stream(CreateJavaInputStreamAdaptor(env, is, storage));
    478 
    479     if (stream.get()) {
    480         // Need to buffer enough input to be able to rewind as much as might be read by a decoder
    481         // trying to determine the stream's format. Currently the most is 64, read by
    482         // SkImageDecoder_libwebp.
    483         // FIXME: Get this number from SkImageDecoder
    484         SkAutoTUnref<SkStreamRewindable> bufferedStream(SkFrontBufferedStream::Create(stream, 64));
    485         SkASSERT(bufferedStream.get() != NULL);
    486         // for now we don't allow purgeable with java inputstreams
    487         bitmap = doDecode(env, bufferedStream, padding, options, false, false);
    488     }
    489     return bitmap;
    490 }
    491 
    492 static jobject nativeDecodeFileDescriptor(JNIEnv* env, jobject clazz, jobject fileDescriptor,
    493         jobject padding, jobject bitmapFactoryOptions) {
    494 
    495     NPE_CHECK_RETURN_ZERO(env, fileDescriptor);
    496 
    497     jint descriptor = jniGetFDFromFileDescriptor(env, fileDescriptor);
    498 
    499     struct stat fdStat;
    500     if (fstat(descriptor, &fdStat) == -1) {
    501         doThrowIOE(env, "broken file descriptor");
    502         return nullObjectReturn("fstat return -1");
    503     }
    504 
    505     bool isPurgeable = optionsPurgeable(env, bitmapFactoryOptions);
    506     bool isShareable = optionsShareable(env, bitmapFactoryOptions);
    507     bool weOwnTheFD = false;
    508     if (isPurgeable && isShareable) {
    509         int newFD = ::dup(descriptor);
    510         if (-1 != newFD) {
    511             weOwnTheFD = true;
    512             descriptor = newFD;
    513         }
    514     }
    515 
    516     SkAutoTUnref<SkData> data(SkData::NewFromFD(descriptor));
    517     if (data.get() == NULL) {
    518         return nullObjectReturn("NewFromFD failed in nativeDecodeFileDescriptor");
    519     }
    520     SkAutoTUnref<SkMemoryStream> stream(new SkMemoryStream(data));
    521 
    522     /* Allow purgeable iff we own the FD, i.e., in the puregeable and
    523        shareable case.
    524     */
    525     return doDecode(env, stream, padding, bitmapFactoryOptions, weOwnTheFD);
    526 }
    527 
    528 static jobject nativeDecodeAsset(JNIEnv* env, jobject clazz, jint native_asset,
    529         jobject padding, jobject options) {
    530 
    531     SkStreamRewindable* stream;
    532     Asset* asset = reinterpret_cast<Asset*>(native_asset);
    533     bool forcePurgeable = optionsPurgeable(env, options);
    534     if (forcePurgeable) {
    535         // if we could "ref/reopen" the asset, we may not need to copy it here
    536         // and we could assume optionsShareable, since assets are always RO
    537         stream = CopyAssetToStream(asset);
    538         if (stream == NULL) {
    539             return NULL;
    540         }
    541     } else {
    542         // since we know we'll be done with the asset when we return, we can
    543         // just use a simple wrapper
    544         stream = new AssetStreamAdaptor(asset);
    545     }
    546     SkAutoUnref aur(stream);
    547     return doDecode(env, stream, padding, options, forcePurgeable, forcePurgeable);
    548 }
    549 
    550 static jobject nativeDecodeByteArray(JNIEnv* env, jobject, jbyteArray byteArray,
    551         int offset, int length, jobject options) {
    552 
    553     /*  If optionsShareable() we could decide to just wrap the java array and
    554         share it, but that means adding a globalref to the java array object
    555         and managing its lifetime. For now we just always copy the array's data
    556         if optionsPurgeable(), unless we're just decoding bounds.
    557      */
    558     bool purgeable = optionsPurgeable(env, options) && !optionsJustBounds(env, options);
    559     AutoJavaByteArray ar(env, byteArray);
    560     SkMemoryStream* stream = new SkMemoryStream(ar.ptr() + offset, length, purgeable);
    561     SkAutoUnref aur(stream);
    562     return doDecode(env, stream, NULL, options, purgeable);
    563 }
    564 
    565 static void nativeRequestCancel(JNIEnv*, jobject joptions) {
    566     (void)AutoDecoderCancel::RequestCancel(joptions);
    567 }
    568 
    569 static jboolean nativeIsSeekable(JNIEnv* env, jobject, jobject fileDescriptor) {
    570     jint descriptor = jniGetFDFromFileDescriptor(env, fileDescriptor);
    571     return ::lseek64(descriptor, 0, SEEK_CUR) != -1 ? JNI_TRUE : JNI_FALSE;
    572 }
    573 
    574 ///////////////////////////////////////////////////////////////////////////////
    575 
    576 static JNINativeMethod gMethods[] = {
    577     {   "nativeDecodeStream",
    578         "(Ljava/io/InputStream;[BLandroid/graphics/Rect;Landroid/graphics/BitmapFactory$Options;)Landroid/graphics/Bitmap;",
    579         (void*)nativeDecodeStream
    580     },
    581 
    582     {   "nativeDecodeFileDescriptor",
    583         "(Ljava/io/FileDescriptor;Landroid/graphics/Rect;Landroid/graphics/BitmapFactory$Options;)Landroid/graphics/Bitmap;",
    584         (void*)nativeDecodeFileDescriptor
    585     },
    586 
    587     {   "nativeDecodeAsset",
    588         "(ILandroid/graphics/Rect;Landroid/graphics/BitmapFactory$Options;)Landroid/graphics/Bitmap;",
    589         (void*)nativeDecodeAsset
    590     },
    591 
    592     {   "nativeDecodeByteArray",
    593         "([BIILandroid/graphics/BitmapFactory$Options;)Landroid/graphics/Bitmap;",
    594         (void*)nativeDecodeByteArray
    595     },
    596 
    597     {   "nativeIsSeekable",
    598         "(Ljava/io/FileDescriptor;)Z",
    599         (void*)nativeIsSeekable
    600     },
    601 };
    602 
    603 static JNINativeMethod gOptionsMethods[] = {
    604     {   "requestCancel", "()V", (void*)nativeRequestCancel }
    605 };
    606 
    607 static jfieldID getFieldIDCheck(JNIEnv* env, jclass clazz,
    608                                 const char fieldname[], const char type[]) {
    609     jfieldID id = env->GetFieldID(clazz, fieldname, type);
    610     SkASSERT(id);
    611     return id;
    612 }
    613 
    614 int register_android_graphics_BitmapFactory(JNIEnv* env) {
    615     jclass options_class = env->FindClass("android/graphics/BitmapFactory$Options");
    616     SkASSERT(options_class);
    617     gOptions_bitmapFieldID = getFieldIDCheck(env, options_class, "inBitmap",
    618         "Landroid/graphics/Bitmap;");
    619     gOptions_justBoundsFieldID = getFieldIDCheck(env, options_class, "inJustDecodeBounds", "Z");
    620     gOptions_sampleSizeFieldID = getFieldIDCheck(env, options_class, "inSampleSize", "I");
    621     gOptions_configFieldID = getFieldIDCheck(env, options_class, "inPreferredConfig",
    622             "Landroid/graphics/Bitmap$Config;");
    623     gOptions_premultipliedFieldID = getFieldIDCheck(env, options_class, "inPremultiplied", "Z");
    624     gOptions_mutableFieldID = getFieldIDCheck(env, options_class, "inMutable", "Z");
    625     gOptions_ditherFieldID = getFieldIDCheck(env, options_class, "inDither", "Z");
    626     gOptions_purgeableFieldID = getFieldIDCheck(env, options_class, "inPurgeable", "Z");
    627     gOptions_shareableFieldID = getFieldIDCheck(env, options_class, "inInputShareable", "Z");
    628     gOptions_preferQualityOverSpeedFieldID = getFieldIDCheck(env, options_class,
    629             "inPreferQualityOverSpeed", "Z");
    630     gOptions_scaledFieldID = getFieldIDCheck(env, options_class, "inScaled", "Z");
    631     gOptions_densityFieldID = getFieldIDCheck(env, options_class, "inDensity", "I");
    632     gOptions_screenDensityFieldID = getFieldIDCheck(env, options_class, "inScreenDensity", "I");
    633     gOptions_targetDensityFieldID = getFieldIDCheck(env, options_class, "inTargetDensity", "I");
    634     gOptions_widthFieldID = getFieldIDCheck(env, options_class, "outWidth", "I");
    635     gOptions_heightFieldID = getFieldIDCheck(env, options_class, "outHeight", "I");
    636     gOptions_mimeFieldID = getFieldIDCheck(env, options_class, "outMimeType", "Ljava/lang/String;");
    637     gOptions_mCancelID = getFieldIDCheck(env, options_class, "mCancel", "Z");
    638 
    639     jclass bitmap_class = env->FindClass("android/graphics/Bitmap");
    640     SkASSERT(bitmap_class);
    641     gBitmap_nativeBitmapFieldID = getFieldIDCheck(env, bitmap_class, "mNativeBitmap", "I");
    642     gBitmap_layoutBoundsFieldID = getFieldIDCheck(env, bitmap_class, "mLayoutBounds", "[I");
    643     int ret = AndroidRuntime::registerNativeMethods(env,
    644                                     "android/graphics/BitmapFactory$Options",
    645                                     gOptionsMethods,
    646                                     SK_ARRAY_COUNT(gOptionsMethods));
    647     if (ret) {
    648         return ret;
    649     }
    650     return android::AndroidRuntime::registerNativeMethods(env, "android/graphics/BitmapFactory",
    651                                          gMethods, SK_ARRAY_COUNT(gMethods));
    652 }
    653