Handle SkStream::rewind properly.
include/core/SkStream.h:
Update documentation to state that rewinding a stream at the beginning
should return true. This is important because our decoders fail if
rewind returns false, assuming that the stream is not at the beginning.
src/images/SkImageDecoder_libpng.cpp:
If rewind fails, call png_error.
src/images/SkImageDecoder_libwebp.cpp:
If rewind fails, report an error and return false.
src/images/SkImageRef.cpp:
If rewind fails report an error and return false.
FIXME: Need to handle flattening properly. Should I perhaps move
writeStream into SkOrderedWriteBuffer?
src/images/SkJpegUtility.cpp:
Report a jpeg error on failure to rewind.
BUG=https://b.corp.google.com/issue?id=8432093
R=bungeman@google.com, djsollen@google.com, reed@google.com
Review URL: https://codereview.chromium.org/22861028
git-svn-id: http://skia.googlecode.com/svn/trunk@10977 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/core/SkStream.h b/include/core/SkStream.h
index d7a105d..27f8ead 100644
--- a/include/core/SkStream.h
+++ b/include/core/SkStream.h
@@ -96,7 +96,9 @@
SkData* readData();
//SkStreamRewindable
- /** Rewinds to the beginning of the stream. If this cannot be done, return false. */
+ /** Rewinds to the beginning of the stream. Returns true if the stream is known
+ * to be at the beginning after this call returns.
+ */
virtual bool rewind() { return false; }
/** Duplicates this stream. If this cannot be done, returns NULL.
diff --git a/src/images/SkImageDecoder_libpng.cpp b/src/images/SkImageDecoder_libpng.cpp
index 85e803b..c188a2f 100644
--- a/src/images/SkImageDecoder_libpng.cpp
+++ b/src/images/SkImageDecoder_libpng.cpp
@@ -124,7 +124,9 @@
#ifdef SK_BUILD_FOR_ANDROID
static void sk_seek_fn(png_structp png_ptr, png_uint_32 offset) {
SkStream* sk_stream = (SkStream*) png_get_io_ptr(png_ptr);
- sk_stream->rewind();
+ if (!sk_stream->rewind()) {
+ png_error(png_ptr, "Failed to rewind stream!");
+ }
(void)sk_stream->skip(offset);
}
#endif
diff --git a/src/images/SkImageDecoder_libwebp.cpp b/src/images/SkImageDecoder_libwebp.cpp
index 9f1116e..7fb1cf0 100644
--- a/src/images/SkImageDecoder_libwebp.cpp
+++ b/src/images/SkImageDecoder_libwebp.cpp
@@ -199,7 +199,10 @@
return false;
}
- stream->rewind();
+ if (!stream->rewind()) {
+ SkDebugf("Failed to rewind webp stream!");
+ return false;
+ }
const size_t readBufferSize = stream->hasLength() ?
SkTMin(stream->getLength(), WEBP_IDECODE_BUFFER_SZ) : WEBP_IDECODE_BUFFER_SZ;
SkAutoMalloc srcStorage(readBufferSize);
@@ -311,7 +314,11 @@
return false;
}
- stream->rewind();
+ if (!stream->rewind()) {
+ SkDebugf("Failed to rewind webp stream!");
+ return false;
+ }
+
*width = origWidth;
*height = origHeight;
diff --git a/src/images/SkImageRef.cpp b/src/images/SkImageRef.cpp
index 299166c..bd4a739 100644
--- a/src/images/SkImageRef.cpp
+++ b/src/images/SkImageRef.cpp
@@ -107,7 +107,10 @@
SkASSERT(fBitmap.getPixels() == NULL);
- fStream->rewind();
+ if (!fStream->rewind()) {
+ SkDEBUGF(("Failed to rewind SkImageRef stream!"));
+ return false;
+ }
SkImageDecoder* codec;
if (fFactory) {
@@ -184,6 +187,15 @@
buffer.writeUInt(fConfig);
buffer.writeInt(fSampleSize);
buffer.writeBool(fDoDither);
- fStream->rewind();
- buffer.writeStream(fStream, fStream->getLength());
+ // FIXME: Consider moving this logic should go into writeStream itself.
+ // writeStream currently has no other callers, so this may be fine for
+ // now.
+ if (!fStream->rewind()) {
+ SkDEBUGF(("Failed to rewind SkImageRef stream!"));
+ buffer.write32(0);
+ } else {
+ // FIXME: Handle getLength properly here. Perhaps this class should
+ // take an SkStreamAsset.
+ buffer.writeStream(fStream, fStream->getLength());
+ }
}
diff --git a/src/images/SkJpegUtility.cpp b/src/images/SkJpegUtility.cpp
index 8d8f62f..1ec9f00 100644
--- a/src/images/SkJpegUtility.cpp
+++ b/src/images/SkJpegUtility.cpp
@@ -16,7 +16,10 @@
#ifdef SK_BUILD_FOR_ANDROID
src->current_offset = 0;
#endif
- src->fStream->rewind();
+ if (!src->fStream->rewind()) {
+ SkDebugf("xxxxxxxxxxxxxx failure to rewind\n");
+ cinfo->err->error_exit((j_common_ptr)cinfo);
+ }
}
#ifdef SK_BUILD_FOR_ANDROID
@@ -27,7 +30,11 @@
if (bo > src->current_offset) {
(void)src->fStream->skip(bo - src->current_offset);
} else {
- src->fStream->rewind();
+ if (!src->fStream->rewind()) {
+ SkDebugf("xxxxxxxxxxxxxx failure to rewind\n");
+ cinfo->err->error_exit((j_common_ptr)cinfo);
+ return false;
+ }
(void)src->fStream->skip(bo);
}