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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Compression.h"
+
+/**
+ * LZ4 is a very fast byte-wise compression algorithm.
+ *
+ * Compared to Google's Snappy it is faster to compress and decompress and
+ * generally produces output of about the same size.
+ *
+ * Compared to zlib it compresses at about 10x the speed, decompresses at about
+ * 4x the speed and produces output of about 1.5x the size.
+ *
+ */
+
+using namespace mozilla::Compression;
+
+/**
+ * Compresses 'inputSize' bytes from 'source' into 'dest'.
+ * Destination buffer must be already allocated,
+ * and must be sized to handle worst cases situations (input data not compressible)
+ * Worst case size evaluation is provided by function LZ4_compressBound()
+ *
+ * @param inputSize is the input size. Max supported value is ~1.9GB
+ * @param return the number of bytes written in buffer dest
+ */
+extern "C" MOZ_EXPORT size_t
+workerlz4_compress(const char* source, size_t inputSize, char* dest) {
+ return LZ4::compress(source, inputSize, dest);
+}
+
+/**
+ * If the source stream is malformed, the function will stop decoding
+ * and return a negative result, indicating the byte position of the
+ * faulty instruction
+ *
+ * This function never writes outside of provided buffers, and never
+ * modifies input buffer.
+ *
+ * note : destination buffer must be already allocated.
+ * its size must be a minimum of 'outputSize' bytes.
+ * @param outputSize is the output size, therefore the original size
+ * @return true/false
+ */
+extern "C" MOZ_EXPORT int
+workerlz4_decompress(const char* source, size_t inputSize,
+ char* dest, size_t maxOutputSize,
+ size_t *bytesOutput) {
+ return LZ4::decompress(source, inputSize,
+ dest, maxOutputSize,
+ bytesOutput);
+}
+
+
+/*
+ Provides the maximum size that LZ4 may output in a "worst case"
+ scenario (input data not compressible) primarily useful for memory
+ allocation of output buffer.
+ note : this function is limited by "int" range (2^31-1)
+
+ @param inputSize is the input size. Max supported value is ~1.9GB
+ @return maximum output size in a "worst case" scenario
+*/
+extern "C" MOZ_EXPORT size_t
+workerlz4_maxCompressedSize(size_t inputSize)
+{
+ return LZ4::maxCompressedSize(inputSize);
+}
+
+
+