| /* |
| * Copyright (C) 2019 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "Gunzip.h" |
| |
| #include <compression.h> |
| |
| namespace PAL { |
| |
| Vector<LChar> gunzip(const unsigned char* data, size_t length) |
| { |
| Vector<LChar> result; |
| |
| // Parse the gzip header. |
| auto checks = [&]() { |
| return length >= 10 && data[0] == 0x1f && data[1] == 0x8b && data[2] == 0x8 && data[3] == 0x0; |
| }; |
| ASSERT(checks()); |
| if (!checks()) |
| return { }; |
| |
| constexpr auto ignoredByteCount = 10; |
| |
| compression_stream stream; |
| auto status = compression_stream_init(&stream, COMPRESSION_STREAM_DECODE, COMPRESSION_ZLIB); |
| ASSERT(status == COMPRESSION_STATUS_OK); |
| if (status != COMPRESSION_STATUS_OK) |
| return { }; |
| stream.dst_ptr = result.data(); |
| stream.dst_size = result.size(); |
| stream.src_ptr = data + ignoredByteCount; |
| stream.src_size = length - ignoredByteCount; |
| size_t offset = 0; |
| |
| do { |
| uint8_t* originalDestinationPointer = stream.dst_ptr; |
| status = compression_stream_process(&stream, COMPRESSION_STREAM_FINALIZE); |
| uint8_t* newDestinationPointer = stream.dst_ptr; |
| offset += newDestinationPointer - originalDestinationPointer; |
| switch (status) { |
| case COMPRESSION_STATUS_OK: { |
| auto newSize = offset * 1.5 + 1; |
| // FIXME: We can get better performance if we, instead of resizing the buffer, we allocate distinct chunks and have a postprocessing step which concatenates the chunks together. |
| if (newSize > result.size()) |
| result.grow(newSize); |
| stream.dst_ptr = result.data() + offset; |
| stream.dst_size = result.size() - offset; |
| break; |
| } |
| case COMPRESSION_STATUS_END: |
| status = compression_stream_destroy(&stream); |
| ASSERT(status == COMPRESSION_STATUS_OK); |
| if (status == COMPRESSION_STATUS_OK) { |
| result.shrink(stream.dst_ptr - result.data()); |
| return result; |
| } |
| return { }; |
| case COMPRESSION_STATUS_ERROR: |
| default: |
| ASSERT_NOT_REACHED(); |
| compression_stream_destroy(&stream); |
| return { }; |
| } |
| } while (true); |
| } |
| |
| } // namespace WTF |