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-rw-r--r--libs/protoutil/src/EncodedBuffer.cpp356
1 files changed, 356 insertions, 0 deletions
diff --git a/libs/protoutil/src/EncodedBuffer.cpp b/libs/protoutil/src/EncodedBuffer.cpp
new file mode 100644
index 000000000000..3a5e2e9ef5d0
--- /dev/null
+++ b/libs/protoutil/src/EncodedBuffer.cpp
@@ -0,0 +1,356 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android/util/EncodedBuffer.h>
+#include <android/util/protobuf.h>
+
+#include <stdlib.h>
+
+namespace android {
+namespace util {
+
+const size_t BUFFER_SIZE = 8 * 1024; // 8 KB
+
+EncodedBuffer::Pointer::Pointer() : Pointer(BUFFER_SIZE)
+{
+}
+
+EncodedBuffer::Pointer::Pointer(size_t chunkSize)
+ :mIndex(0),
+ mOffset(0)
+{
+ mChunkSize = chunkSize == 0 ? BUFFER_SIZE : chunkSize;
+}
+
+size_t
+EncodedBuffer::Pointer::pos() const
+{
+ return mIndex * mChunkSize + mOffset;
+}
+
+size_t
+EncodedBuffer::Pointer::index() const
+{
+ return mIndex;
+}
+
+size_t
+EncodedBuffer::Pointer::offset() const
+{
+ return mOffset;
+}
+
+EncodedBuffer::Pointer*
+EncodedBuffer::Pointer::move(size_t amt)
+{
+ size_t newOffset = mOffset + amt;
+ mIndex += newOffset / mChunkSize;
+ mOffset = newOffset % mChunkSize;
+ return this;
+}
+
+EncodedBuffer::Pointer*
+EncodedBuffer::Pointer::rewind()
+{
+ mIndex = 0;
+ mOffset = 0;
+ return this;
+}
+
+EncodedBuffer::Pointer
+EncodedBuffer::Pointer::copy() const
+{
+ Pointer p = Pointer(mChunkSize);
+ p.mIndex = mIndex;
+ p.mOffset = mOffset;
+ return p;
+}
+
+// ===========================================================
+EncodedBuffer::EncodedBuffer() : EncodedBuffer(0)
+{
+}
+
+EncodedBuffer::EncodedBuffer(size_t chunkSize)
+ :mBuffers()
+{
+ mChunkSize = chunkSize == 0 ? BUFFER_SIZE : chunkSize;
+ mWp = Pointer(mChunkSize);
+ mEp = Pointer(mChunkSize);
+}
+
+EncodedBuffer::~EncodedBuffer()
+{
+ for (size_t i=0; i<mBuffers.size(); i++) {
+ uint8_t* buf = mBuffers[i];
+ free(buf);
+ }
+}
+
+inline uint8_t*
+EncodedBuffer::at(const Pointer& p) const
+{
+ return mBuffers[p.index()] + p.offset();
+}
+
+void
+EncodedBuffer::clear()
+{
+ mWp.rewind();
+ mEp.rewind();
+}
+
+/******************************** Write APIs ************************************************/
+size_t
+EncodedBuffer::size() const
+{
+ return mWp.pos();
+}
+
+EncodedBuffer::Pointer*
+EncodedBuffer::wp()
+{
+ return &mWp;
+}
+
+uint8_t*
+EncodedBuffer::writeBuffer()
+{
+ // This prevents write pointer move too fast than allocating the buffer.
+ if (mWp.index() > mBuffers.size()) return NULL;
+ uint8_t* buf = NULL;
+ if (mWp.index() == mBuffers.size()) {
+ buf = (uint8_t*)malloc(mChunkSize);
+
+ if (buf == NULL) return NULL; // This indicates NO_MEMORY
+
+ mBuffers.push_back(buf);
+ }
+ return at(mWp);
+}
+
+size_t
+EncodedBuffer::currentToWrite()
+{
+ return mChunkSize - mWp.offset();
+}
+
+void
+EncodedBuffer::writeRawByte(uint8_t val)
+{
+ *writeBuffer() = val;
+ mWp.move();
+}
+
+size_t
+EncodedBuffer::writeRawVarint64(uint64_t val)
+{
+ size_t size = 0;
+ while (true) {
+ size++;
+ if ((val & ~0x7F) == 0) {
+ writeRawByte((uint8_t) val);
+ return size;
+ } else {
+ writeRawByte((uint8_t)((val & 0x7F) | 0x80));
+ val >>= 7;
+ }
+ }
+}
+
+size_t
+EncodedBuffer::writeRawVarint32(uint32_t val)
+{
+ uint64_t v =(uint64_t)val;
+ return writeRawVarint64(v);
+}
+
+void
+EncodedBuffer::writeRawFixed32(uint32_t val)
+{
+ writeRawByte((uint8_t) val);
+ writeRawByte((uint8_t) (val>>8));
+ writeRawByte((uint8_t) (val>>16));
+ writeRawByte((uint8_t) (val>>24));
+}
+
+void
+EncodedBuffer::writeRawFixed64(uint64_t val)
+{
+ writeRawByte((uint8_t) val);
+ writeRawByte((uint8_t) (val>>8));
+ writeRawByte((uint8_t) (val>>16));
+ writeRawByte((uint8_t) (val>>24));
+ writeRawByte((uint8_t) (val>>32));
+ writeRawByte((uint8_t) (val>>40));
+ writeRawByte((uint8_t) (val>>48));
+ writeRawByte((uint8_t) (val>>56));
+}
+
+size_t
+EncodedBuffer::writeHeader(uint32_t fieldId, uint8_t wireType)
+{
+ return writeRawVarint32((fieldId << FIELD_ID_SHIFT) | wireType);
+}
+
+/******************************** Edit APIs ************************************************/
+EncodedBuffer::Pointer*
+EncodedBuffer::ep()
+{
+ return &mEp;
+}
+
+uint8_t
+EncodedBuffer::readRawByte()
+{
+ uint8_t val = *at(mEp);
+ mEp.move();
+ return val;
+}
+
+uint64_t
+EncodedBuffer::readRawVarint()
+{
+ uint64_t val = 0, shift = 0;
+ size_t start = mEp.pos();
+ while (true) {
+ uint8_t byte = readRawByte();
+ val += (byte & 0x7F) << shift;
+ if ((byte & 0x80) == 0) break;
+ shift += 7;
+ }
+ return val;
+}
+
+uint32_t
+EncodedBuffer::readRawFixed32()
+{
+ uint32_t val = 0;
+ for (auto i=0; i<32; i+=8) {
+ val += (uint32_t)readRawByte() << i;
+ }
+ return val;
+}
+
+uint64_t
+EncodedBuffer::readRawFixed64()
+{
+ uint64_t val = 0;
+ for (auto i=0; i<64; i+=8) {
+ val += (uint64_t)readRawByte() << i;
+ }
+ return val;
+}
+
+void
+EncodedBuffer::editRawFixed32(size_t pos, uint32_t val)
+{
+ size_t oldPos = mEp.pos();
+ mEp.rewind()->move(pos);
+ for (auto i=0; i<32; i+=8) {
+ *at(mEp) = (uint8_t) (val >> i);
+ mEp.move();
+ }
+ mEp.rewind()->move(oldPos);
+}
+
+void
+EncodedBuffer::copy(size_t srcPos, size_t size)
+{
+ if (size == 0) return;
+ Pointer cp(mChunkSize);
+ cp.move(srcPos);
+
+ while (cp.pos() < srcPos + size) {
+ writeRawByte(*at(cp));
+ cp.move();
+ }
+}
+
+/********************************* Read APIs ************************************************/
+EncodedBuffer::iterator
+EncodedBuffer::begin() const
+{
+ return EncodedBuffer::iterator(*this);
+}
+
+EncodedBuffer::iterator::iterator(const EncodedBuffer& buffer)
+ :mData(buffer),
+ mRp(buffer.mChunkSize)
+{
+}
+
+size_t
+EncodedBuffer::iterator::size() const
+{
+ return mData.size();
+}
+
+size_t
+EncodedBuffer::iterator::bytesRead() const
+{
+ return mRp.pos();
+}
+
+EncodedBuffer::Pointer*
+EncodedBuffer::iterator::rp()
+{
+ return &mRp;
+}
+
+uint8_t const*
+EncodedBuffer::iterator::readBuffer()
+{
+ return hasNext() ? const_cast<uint8_t const*>(mData.at(mRp)) : NULL;
+}
+
+size_t
+EncodedBuffer::iterator::currentToRead()
+{
+ return (mData.mWp.index() > mRp.index()) ?
+ mData.mChunkSize - mRp.offset() :
+ mData.mWp.offset() - mRp.offset();
+}
+
+bool
+EncodedBuffer::iterator::hasNext()
+{
+ return mRp.pos() < mData.mWp.pos();
+}
+
+uint8_t
+EncodedBuffer::iterator::next()
+{
+ uint8_t res = *(mData.at(mRp));
+ mRp.move();
+ return res;
+}
+
+uint64_t
+EncodedBuffer::iterator::readRawVarint()
+{
+ uint64_t val = 0, shift = 0;
+ while (true) {
+ uint8_t byte = next();
+ val += (byte & 0x7F) << shift;
+ if ((byte & 0x80) == 0) break;
+ shift += 7;
+ }
+ return val;
+}
+
+} // util
+} // android