Call rewindIfNeeded in SkCodec
Rather than calling it in each subclass, call it once in the base
class. Call it first, since other steps may modify internal structures
which would be replaced by a call to onRewind.
BUG=skia:4284
Review URL: https://codereview.chromium.org/1381483002
diff --git a/include/codec/SkCodec.h b/include/codec/SkCodec.h
index 01fd4fa..c0cce85 100644
--- a/include/codec/SkCodec.h
+++ b/include/codec/SkCodec.h
@@ -402,9 +402,8 @@
* @returns true if the codec is at the right position and can be used.
* false if there was a failure to rewind.
*
- * Subclasses MUST call this function before reading the stream (e.g. in
- * onGetPixels). If it returns false, onGetPixels should return
- * kCouldNotRewind.
+ * This is called by getPixels() and start(). Subclasses may call if they
+ * need to rewind at another time.
*/
bool SK_WARN_UNUSED_RESULT rewindIfNeeded();
diff --git a/src/codec/SkBmpCodec.cpp b/src/codec/SkBmpCodec.cpp
index 4e801f0..4ae57c0 100644
--- a/src/codec/SkBmpCodec.cpp
+++ b/src/codec/SkBmpCodec.cpp
@@ -576,9 +576,6 @@
SkCodec::Result SkBmpCodec::onStartScanlineDecode(const SkImageInfo& dstInfo,
const SkCodec::Options& options, SkPMColor inputColorPtr[], int* inputColorCount) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
if (options.fSubset) {
// Subsets are not supported.
return kUnimplemented;
diff --git a/src/codec/SkBmpMaskCodec.cpp b/src/codec/SkBmpMaskCodec.cpp
index 2e88d54..81067c7 100644
--- a/src/codec/SkBmpMaskCodec.cpp
+++ b/src/codec/SkBmpMaskCodec.cpp
@@ -30,9 +30,6 @@
const Options& opts,
SkPMColor* inputColorPtr,
int* inputColorCount) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
if (opts.fSubset) {
// Subsets are not supported.
return kUnimplemented;
diff --git a/src/codec/SkBmpRLECodec.cpp b/src/codec/SkBmpRLECodec.cpp
index 79dd633..e76a23e 100644
--- a/src/codec/SkBmpRLECodec.cpp
+++ b/src/codec/SkBmpRLECodec.cpp
@@ -39,9 +39,6 @@
const Options& opts,
SkPMColor* inputColorPtr,
int* inputColorCount) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
if (opts.fSubset) {
// Subsets are not supported.
return kUnimplemented;
diff --git a/src/codec/SkBmpStandardCodec.cpp b/src/codec/SkBmpStandardCodec.cpp
index 02f2d42..5e65ebb 100644
--- a/src/codec/SkBmpStandardCodec.cpp
+++ b/src/codec/SkBmpStandardCodec.cpp
@@ -37,9 +37,6 @@
const Options& opts,
SkPMColor* inputColorPtr,
int* inputColorCount) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
if (opts.fSubset) {
// Subsets are not supported.
return kUnimplemented;
diff --git a/src/codec/SkCodec.cpp b/src/codec/SkCodec.cpp
index 97bcf3e..cabcadc 100644
--- a/src/codec/SkCodec.cpp
+++ b/src/codec/SkCodec.cpp
@@ -87,6 +87,12 @@
SkCodec::~SkCodec() {}
bool SkCodec::rewindIfNeeded() {
+ if (!fStream) {
+ // Some codecs do not have a stream, but they hold others that do. They
+ // must handle rewinding themselves.
+ return true;
+ }
+
// Store the value of fNeedsRewind so we can update it. Next read will
// require a rewind.
const bool needsRewind = fNeedsRewind;
@@ -138,6 +144,10 @@
}
}
+ if (!this->rewindIfNeeded()) {
+ return kCouldNotRewind;
+ }
+
// Default options.
Options optsStorage;
if (nullptr == options) {
@@ -172,6 +182,10 @@
ctable = nullptr;
}
+ if (!this->rewindIfNeeded()) {
+ return kCouldNotRewind;
+ }
+
// Set options.
Options optsStorage;
if (nullptr == options) {
diff --git a/src/codec/SkCodec_libgif.cpp b/src/codec/SkCodec_libgif.cpp
index ad7fb5b..e6d1141 100644
--- a/src/codec/SkCodec_libgif.cpp
+++ b/src/codec/SkCodec_libgif.cpp
@@ -456,11 +456,6 @@
SkCodec::Result SkGifCodec::prepareToDecode(const SkImageInfo& dstInfo, SkPMColor* inputColorPtr,
int* inputColorCount, const Options& opts) {
- // Rewind if necessary
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
-
// Check for valid input parameters
if (opts.fSubset) {
// Subsets are not supported.
diff --git a/src/codec/SkCodec_libgif.h b/src/codec/SkCodec_libgif.h
index 3999c41..d7dc2b9 100644
--- a/src/codec/SkCodec_libgif.h
+++ b/src/codec/SkCodec_libgif.h
@@ -108,7 +108,7 @@
int* inputColorCount);
/*
- * Checks for invalid inputs and calls rewindIfNeeded(), setFramDimensions(), and
+ * Checks for invalid inputs and calls setFrameDimensions(), and
* initializeColorTable() in the proper sequence.
*/
Result prepareToDecode(const SkImageInfo& dstInfo, SkPMColor* inputColorPtr,
diff --git a/src/codec/SkCodec_libpng.cpp b/src/codec/SkCodec_libpng.cpp
index faba79f..1af8658 100644
--- a/src/codec/SkCodec_libpng.cpp
+++ b/src/codec/SkCodec_libpng.cpp
@@ -477,9 +477,6 @@
if (requestedInfo.dimensions() != this->getInfo().dimensions()) {
return kInvalidScale;
}
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
// Note that ctable and ctableCount may be modified if there is a color table
const Result result = this->initializeSwizzler(requestedInfo, options,
@@ -592,10 +589,6 @@
Result onStartScanlineDecode(const SkImageInfo& dstInfo, const Options& options,
SkPMColor ctable[], int* ctableCount) override {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
-
if (!conversion_possible(dstInfo, this->getInfo())) {
return kInvalidConversion;
}
@@ -690,10 +683,6 @@
Result onStartScanlineDecode(const SkImageInfo& dstInfo, const Options& options,
SkPMColor ctable[], int* ctableCount) override
{
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
-
if (!conversion_possible(dstInfo, this->getInfo())) {
return kInvalidConversion;
}
diff --git a/src/codec/SkCodec_wbmp.cpp b/src/codec/SkCodec_wbmp.cpp
index 0c85ead..1696dfb 100644
--- a/src/codec/SkCodec_wbmp.cpp
+++ b/src/codec/SkCodec_wbmp.cpp
@@ -110,9 +110,6 @@
const Options& options,
SkPMColor ctable[],
int* ctableCount) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
if (options.fSubset) {
// Subsets are not supported.
return kUnimplemented;
@@ -180,9 +177,6 @@
SkCodec::Result SkWbmpCodec::onStartScanlineDecode(const SkImageInfo& dstInfo,
const Options& options, SkPMColor inputColorTable[], int* inputColorCount) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
if (options.fSubset) {
// Subsets are not supported.
return kUnimplemented;
diff --git a/src/codec/SkJpegCodec.cpp b/src/codec/SkJpegCodec.cpp
index dac0c17..b4c794c 100644
--- a/src/codec/SkJpegCodec.cpp
+++ b/src/codec/SkJpegCodec.cpp
@@ -303,11 +303,6 @@
SkCodec::Result SkJpegCodec::onGetPixels(const SkImageInfo& dstInfo,
void* dst, size_t dstRowBytes,
const Options& options, SkPMColor*, int*) {
- // Rewind the stream if needed
- if (!this->rewindIfNeeded()) {
- return fDecoderMgr->returnFailure("could not rewind stream", kCouldNotRewind);
- }
-
if (options.fSubset) {
// Subsets are not supported.
return kUnimplemented;
@@ -412,11 +407,6 @@
SkCodec::Result SkJpegCodec::onStartScanlineDecode(const SkImageInfo& dstInfo,
const Options& options, SkPMColor ctable[], int* ctableCount) {
- // Rewind the stream if needed
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
-
// Set the jump location for libjpeg errors
if (setjmp(fDecoderMgr->getJmpBuf())) {
SkCodecPrintf("setjmp: Error from libjpeg\n");
diff --git a/src/codec/SkWebpCodec.cpp b/src/codec/SkWebpCodec.cpp
index ccf4964..5970bae 100644
--- a/src/codec/SkWebpCodec.cpp
+++ b/src/codec/SkWebpCodec.cpp
@@ -152,10 +152,6 @@
SkCodec::Result SkWebpCodec::onGetPixels(const SkImageInfo& dstInfo, void* dst, size_t rowBytes,
const Options& options, SkPMColor*, int*) {
- if (!this->rewindIfNeeded()) {
- return kCouldNotRewind;
- }
-
if (!webp_conversion_possible(dstInfo, this->getInfo())) {
return kInvalidConversion;
}