// Note: if the newSize == kReadToEnd (0), this function will read to the end of stream.
bool bufferMoreData(size_t newSize) {
if (newSize == kReadToEnd) {
if (fWholeStreamRead) { // already read-to-end.
return true;
}
// TODO: optimize for the special case when the input is SkMemoryStream.
return SkStreamCopy(&fStreamBuffer, fStream.get());
}
if (newSize <= fStreamBuffer.bytesWritten()) { // already buffered to newSize
return true;
}
if (fWholeStreamRead) { // newSize is larger than the whole stream.
return false;
}
// Try to read at least 8192 bytes to avoid to many small reads.
const size_t kMinSizeToRead = 8192;
const size_t sizeRequested = newSize - fStreamBuffer.bytesWritten();
const size_t sizeToRead = SkTMax(kMinSizeToRead, sizeRequested);
SkAutoSTMalloc<kMinSizeToRead, uint8> tempBuffer(sizeToRead);
const size_t bytesRead = fStream->read(tempBuffer.get(), sizeToRead);
if (bytesRead < sizeRequested) {
return false;
}
return fStreamBuffer.write(tempBuffer.get(), bytesRead);
}
static void stream_copy_test(skiatest::Reporter* reporter,
const void* srcData,
size_t N,
SkStream* stream) {
SkDynamicMemoryWStream tgt;
if (!SkStreamCopy(&tgt, stream)) {
ERRORF(reporter, "SkStreamCopy failed");
return;
}
sk_sp<SkData> data(tgt.detachAsData());
if (data->size() != N) {
ERRORF(reporter, "SkStreamCopy incorrect size");
return;
}
if (0 != memcmp(data->data(), srcData, N)) {
ERRORF(reporter, "SkStreamCopy bad copy");
}
}
