Index: src/utils/SkFrontBufferedStream.cpp |
diff --git a/src/utils/SkFrontBufferedStream.cpp b/src/utils/SkFrontBufferedStream.cpp |
index d68b9e44fd9d1b05bd0fb8f391b46b4c86d2fad3..d44389b7c81ad4c8bdfd625b4f0c29d2625a6742 100644 |
--- a/src/utils/SkFrontBufferedStream.cpp |
+++ b/src/utils/SkFrontBufferedStream.cpp |
@@ -6,22 +6,76 @@ |
*/ |
#include "SkFrontBufferedStream.h" |
+#include "SkStream.h" |
+#include "SkTemplates.h" |
+ |
+class FrontBufferedStream : public SkStreamRewindable { |
+public: |
+ // Called by Create. |
+ FrontBufferedStream(SkStream*, size_t bufferSize); |
+ |
+ virtual size_t read(void* buffer, size_t size) SK_OVERRIDE; |
+ |
+ virtual bool isAtEnd() const SK_OVERRIDE; |
+ |
+ virtual bool rewind() SK_OVERRIDE; |
+ |
+ virtual bool hasPosition() const SK_OVERRIDE { return true; } |
+ |
+ virtual size_t getPosition() const SK_OVERRIDE { return fOffset; } |
+ |
+ virtual bool hasLength() const SK_OVERRIDE; |
+ |
+ virtual size_t getLength() const SK_OVERRIDE; |
+ |
+ virtual SkStreamRewindable* duplicate() const SK_OVERRIDE { return NULL; } |
+ |
+private: |
+ SkAutoTUnref<SkStream> fStream; |
+ // Current offset into the stream. Always >= 0. |
+ size_t fOffset; |
+ // Amount that has been buffered by calls to read. Will always be less than |
+ // fBufferSize. |
+ size_t fBufferedSoFar; |
+ // Total size of the buffer. |
+ const size_t fBufferSize; |
+ // FIXME: SkAutoTMalloc throws on failure. Instead, Create should return a |
+ // NULL stream. |
+ SkAutoTMalloc<char> fBuffer; |
+ |
+ // Read up to size bytes from already buffered data, and copy to |
+ // dst, if non-NULL. Updates fOffset. Assumes that fOffset is less |
+ // than fBufferedSoFar. |
+ size_t readFromBuffer(char* dst, size_t size); |
+ |
+ // Buffer up to size bytes from the stream, and copy to dst if non- |
+ // NULL. Updates fOffset and fBufferedSoFar. Assumes that fOffset is |
+ // less than fBufferedSoFar, and size is greater than 0. |
+ size_t bufferAndWriteTo(char* dst, size_t size); |
+ |
+ // Read up to size bytes directly from the stream and into dst if non- |
+ // NULL. Updates fOffset. Assumes fOffset is at or beyond the buffered |
+ // data, and size is greater than 0. |
+ size_t readDirectlyFromStream(char* dst, size_t size); |
+ |
+ typedef SkStream INHERITED; |
+}; |
SkStreamRewindable* SkFrontBufferedStream::Create(SkStream* stream, size_t bufferSize) { |
if (NULL == stream) { |
return NULL; |
} |
- return SkNEW_ARGS(SkFrontBufferedStream, (stream, bufferSize)); |
+ return SkNEW_ARGS(FrontBufferedStream, (stream, bufferSize)); |
} |
-SkFrontBufferedStream::SkFrontBufferedStream(SkStream* stream, size_t bufferSize) |
+FrontBufferedStream::FrontBufferedStream(SkStream* stream, size_t bufferSize) |
: fStream(SkRef(stream)) |
, fOffset(0) |
, fBufferedSoFar(0) |
, fBufferSize(bufferSize) |
, fBuffer(bufferSize) {} |
-bool SkFrontBufferedStream::isAtEnd() const { |
+bool FrontBufferedStream::isAtEnd() const { |
if (fOffset < fBufferedSoFar) { |
// Even if the underlying stream is at the end, this stream has been |
// rewound after buffering, so it is not at the end. |
@@ -31,7 +85,7 @@ bool SkFrontBufferedStream::isAtEnd() const { |
return fStream->isAtEnd(); |
} |
-bool SkFrontBufferedStream::rewind() { |
+bool FrontBufferedStream::rewind() { |
// Only allow a rewind if we have not exceeded the buffer. |
if (fOffset <= fBufferSize) { |
fOffset = 0; |
@@ -40,15 +94,15 @@ bool SkFrontBufferedStream::rewind() { |
return false; |
} |
-bool SkFrontBufferedStream::hasLength() const { |
+bool FrontBufferedStream::hasLength() const { |
return fStream->hasLength(); |
} |
-size_t SkFrontBufferedStream::getLength() const { |
+size_t FrontBufferedStream::getLength() const { |
return fStream->getLength(); |
} |
-size_t SkFrontBufferedStream::readFromBuffer(char* dst, size_t size) { |
+size_t FrontBufferedStream::readFromBuffer(char* dst, size_t size) { |
SkASSERT(fOffset < fBufferedSoFar); |
// Some data has already been copied to fBuffer. Read up to the |
// lesser of the size requested and the remainder of the buffered |
@@ -66,7 +120,7 @@ size_t SkFrontBufferedStream::readFromBuffer(char* dst, size_t size) { |
return bytesToCopy; |
} |
-size_t SkFrontBufferedStream::bufferAndWriteTo(char* dst, size_t size) { |
+size_t FrontBufferedStream::bufferAndWriteTo(char* dst, size_t size) { |
SkASSERT(size > 0); |
SkASSERT(fOffset >= fBufferedSoFar); |
// Data needs to be buffered. Buffer up to the lesser of the size requested |
@@ -87,7 +141,7 @@ size_t SkFrontBufferedStream::bufferAndWriteTo(char* dst, size_t size) { |
return buffered; |
} |
-size_t SkFrontBufferedStream::readDirectlyFromStream(char* dst, size_t size) { |
+size_t FrontBufferedStream::readDirectlyFromStream(char* dst, size_t size) { |
SkASSERT(size > 0); |
// If we get here, we have buffered all that can be buffered. |
SkASSERT(fBufferSize == fBufferedSoFar && fOffset >= fBufferSize); |
@@ -104,7 +158,7 @@ size_t SkFrontBufferedStream::readDirectlyFromStream(char* dst, size_t size) { |
return bytesReadDirectly; |
} |
-size_t SkFrontBufferedStream::read(void* voidDst, size_t size) { |
+size_t FrontBufferedStream::read(void* voidDst, size_t size) { |
// Cast voidDst to a char* for easy addition. |
char* dst = reinterpret_cast<char*>(voidDst); |
SkDEBUGCODE(const size_t totalSize = size;) |