add serial procs to pictures

Bug: skia:7380
Change-Id: Ic1b7e437316c7913711cf5cb119e3fe904cd2c05
Reviewed-on: https://skia-review.googlesource.com/76980
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>

1 files changed, 40 insertions, 18 deletions

diff --git a/src/core/SkReadBuffer.cpp b/src/core/SkReadBuffer.cpp
index 628e3af062..b1d7808dcb 100644
--- a/src/core/SkReadBuffer.cpp
+++ b/src/core/SkReadBuffer.cpp
@@ -44,9 +44,6 @@ static uint32_t default_flags() {
     return flags;
 }
 
-// This has an empty constructor and destructor, and is thread-safe, so we can use a singleton.
-static SkImageDeserializer gDefaultImageDeserializer;
-
 SkReadBuffer::SkReadBuffer() {
     fFlags = default_flags();
     fVersion = 0;
@@ -57,7 +54,6 @@ SkReadBuffer::SkReadBuffer() {
 
     fFactoryArray = nullptr;
     fFactoryCount = 0;
-    fImageDeserializer = &gDefaultImageDeserializer;
 #ifdef DEBUG_NON_DETERMINISTIC_ASSERT
     fDecodedBitmapIndex = -1;
 #endif // DEBUG_NON_DETERMINISTIC_ASSERT
@@ -74,7 +70,6 @@ SkReadBuffer::SkReadBuffer(const void* data, size_t size) {
 
     fFactoryArray = nullptr;
     fFactoryCount = 0;
-    fImageDeserializer = &gDefaultImageDeserializer;
 #ifdef DEBUG_NON_DETERMINISTIC_ASSERT
     fDecodedBitmapIndex = -1;
 #endif // DEBUG_NON_DETERMINISTIC_ASSERT
@@ -93,7 +88,6 @@ SkReadBuffer::SkReadBuffer(SkStream* stream) {
 
     fFactoryArray = nullptr;
     fFactoryCount = 0;
-    fImageDeserializer = &gDefaultImageDeserializer;
 #ifdef DEBUG_NON_DETERMINISTIC_ASSERT
     fDecodedBitmapIndex = -1;
 #endif // DEBUG_NON_DETERMINISTIC_ASSERT
@@ -103,8 +97,8 @@ SkReadBuffer::~SkReadBuffer() {
     sk_free(fMemoryPtr);
 }
 
-void SkReadBuffer::setImageDeserializer(SkImageDeserializer* deserializer) {
-    fImageDeserializer = deserializer ? deserializer : &gDefaultImageDeserializer;
+void SkReadBuffer::setDeserialProcs(const SkDeserialProcs& procs) {
+    fProcs = procs;
 }
 
 bool SkReadBuffer::readBool() {
@@ -131,6 +125,14 @@ int32_t SkReadBuffer::read32() {
     return fReader.readInt();
 }
 
+bool SkReadBuffer::readPad32(void* buffer, size_t bytes) {
+    if (!fReader.isAvailable(bytes)) {
+        return false;
+    }
+    fReader.read(buffer, bytes);
+    return true;
+}
+
 uint8_t SkReadBuffer::peekByte() {
     SkASSERT(fReader.available() > 0);
     return *((uint8_t*) fReader.peek());
@@ -235,10 +237,16 @@ sk_sp<SkImage> SkReadBuffer::readImage() {
         return nullptr;
     }
 
-    uint32_t encoded_size = this->getArrayCount();
+    /*
+     *  What follows is a 32bit encoded size.
+     *   0 : failure, nothing else to do
+     *  <0 : negative (int32_t) of a custom encoded blob using SerialProcs
+     *  >0 : standard encoded blob size (use MakeFromEncoded)
+     */
+
+    int32_t encoded_size = this->read32();
     if (encoded_size == 0) {
         // The image could not be encoded at serialization time - return an empty placeholder.
-        (void)this->readUInt();  // Swallow that encoded_size == 0 sentinel.
         return MakeEmptyImage(width, height);
     }
     if (encoded_size == 1) {
@@ -247,19 +255,33 @@ sk_sp<SkImage> SkReadBuffer::readImage() {
         return nullptr;
     }
 
-    // The SkImage encoded itself.
-    sk_sp<SkData> encoded(this->readByteArrayAsData());
-
-    int originX = this->read32();
-    int originY = this->read32();
+    size_t size = SkAbs32(encoded_size);
+    sk_sp<SkData> data = SkData::MakeUninitialized(size);
+    if (!this->readPad32(data->writable_data(), size)) {
+        this->validate(false);
+        return nullptr;
+    }
+    int32_t originX = this->read32();
+    int32_t originY = this->read32();
     if (originX < 0 || originY < 0) {
         this->validate(false);
         return nullptr;
     }
 
-    const SkIRect subset = SkIRect::MakeXYWH(originX, originY, width, height);
-
-    sk_sp<SkImage> image = fImageDeserializer->makeFromData(encoded.get(), &subset);
+    sk_sp<SkImage> image;
+    if (encoded_size < 0) {     // custom encoded, need serial proc
+        if (fProcs.fImageProc) {
+            image = fProcs.fImageProc(data->data(), data->size(), fProcs.fImageCtx);
+        } else {
+            // Nothing to do (no client proc), but since we've already "read" the custom data,
+            // wee just leave image as nullptr.
+        }
+    } else {
+        SkIRect subset = SkIRect::MakeXYWH(originX, originY, width, height);
+        image = SkImage::MakeFromEncoded(std::move(data), &subset);
+    }
+    // Question: are we correct to return an "empty" image instead of nullptr, if the decoder
+    //           failed for some reason?
     return image ? image : MakeEmptyImage(width, height);
 }