/*************************************************************************/ /* compression.cpp */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */ /* */ /* Permission is hereby granted, free of charge, to any person obtaining */ /* a copy of this software and associated documentation files (the */ /* "Software"), to deal in the Software without restriction, including */ /* without limitation the rights to use, copy, modify, merge, publish, */ /* distribute, sublicense, and/or sell copies of the Software, and to */ /* permit persons to whom the Software is furnished to do so, subject to */ /* the following conditions: */ /* */ /* The above copyright notice and this permission notice shall be */ /* included in all copies or substantial portions of the Software. */ /* */ /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/ /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /*************************************************************************/ #include "compression.h" #include "core/config/project_settings.h" #include "core/io/zip_io.h" #include "core/os/copymem.h" #include "thirdparty/misc/fastlz.h" #include <zlib.h> #include <zstd.h> int Compression::compress(uint8_t *p_dst, const uint8_t *p_src, int p_src_size, Mode p_mode) { switch (p_mode) { case MODE_FASTLZ: { if (p_src_size < 16) { uint8_t src[16]; zeromem(&src[p_src_size], 16 - p_src_size); copymem(src, p_src, p_src_size); return fastlz_compress(src, 16, p_dst); } else { return fastlz_compress(p_src, p_src_size, p_dst); } } break; case MODE_DEFLATE: case MODE_GZIP: { int window_bits = p_mode == MODE_DEFLATE ? 15 : 15 + 16; z_stream strm; strm.zalloc = zipio_alloc; strm.zfree = zipio_free; strm.opaque = Z_NULL; int level = p_mode == MODE_DEFLATE ? zlib_level : gzip_level; int err = deflateInit2(&strm, level, Z_DEFLATED, window_bits, 8, Z_DEFAULT_STRATEGY); if (err != Z_OK) { return -1; } strm.avail_in = p_src_size; int aout = deflateBound(&strm, p_src_size); strm.avail_out = aout; strm.next_in = (Bytef *)p_src; strm.next_out = p_dst; deflate(&strm, Z_FINISH); aout = aout - strm.avail_out; deflateEnd(&strm); return aout; } break; case MODE_ZSTD: { ZSTD_CCtx *cctx = ZSTD_createCCtx(); ZSTD_CCtx_setParameter(cctx, ZSTD_c_compressionLevel, zstd_level); if (zstd_long_distance_matching) { ZSTD_CCtx_setParameter(cctx, ZSTD_c_enableLongDistanceMatching, 1); ZSTD_CCtx_setParameter(cctx, ZSTD_c_windowLog, zstd_window_log_size); } int max_dst_size = get_max_compressed_buffer_size(p_src_size, MODE_ZSTD); int ret = ZSTD_compressCCtx(cctx, p_dst, max_dst_size, p_src, p_src_size, zstd_level); ZSTD_freeCCtx(cctx); return ret; } break; } ERR_FAIL_V(-1); } int Compression::get_max_compressed_buffer_size(int p_src_size, Mode p_mode) { switch (p_mode) { case MODE_FASTLZ: { int ss = p_src_size + p_src_size * 6 / 100; if (ss < 66) { ss = 66; } return ss; } break; case MODE_DEFLATE: case MODE_GZIP: { int window_bits = p_mode == MODE_DEFLATE ? 15 : 15 + 16; z_stream strm; strm.zalloc = zipio_alloc; strm.zfree = zipio_free; strm.opaque = Z_NULL; int err = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, Z_DEFLATED, window_bits, 8, Z_DEFAULT_STRATEGY); if (err != Z_OK) { return -1; } int aout = deflateBound(&strm, p_src_size); deflateEnd(&strm); return aout; } break; case MODE_ZSTD: { return ZSTD_compressBound(p_src_size); } break; } ERR_FAIL_V(-1); } int Compression::decompress(uint8_t *p_dst, int p_dst_max_size, const uint8_t *p_src, int p_src_size, Mode p_mode) { switch (p_mode) { case MODE_FASTLZ: { int ret_size = 0; if (p_dst_max_size < 16) { uint8_t dst[16]; ret_size = fastlz_decompress(p_src, p_src_size, dst, 16); copymem(p_dst, dst, p_dst_max_size); } else { ret_size = fastlz_decompress(p_src, p_src_size, p_dst, p_dst_max_size); } return ret_size; } break; case MODE_DEFLATE: case MODE_GZIP: { int window_bits = p_mode == MODE_DEFLATE ? 15 : 15 + 16; z_stream strm; strm.zalloc = zipio_alloc; strm.zfree = zipio_free; strm.opaque = Z_NULL; strm.avail_in = 0; strm.next_in = Z_NULL; int err = inflateInit2(&strm, window_bits); ERR_FAIL_COND_V(err != Z_OK, -1); strm.avail_in = p_src_size; strm.avail_out = p_dst_max_size; strm.next_in = (Bytef *)p_src; strm.next_out = p_dst; err = inflate(&strm, Z_FINISH); int total = strm.total_out; inflateEnd(&strm); ERR_FAIL_COND_V(err != Z_STREAM_END, -1); return total; } break; case MODE_ZSTD: { ZSTD_DCtx *dctx = ZSTD_createDCtx(); if (zstd_long_distance_matching) { ZSTD_DCtx_setParameter(dctx, ZSTD_d_windowLogMax, zstd_window_log_size); } int ret = ZSTD_decompressDCtx(dctx, p_dst, p_dst_max_size, p_src, p_src_size); ZSTD_freeDCtx(dctx); return ret; } break; } ERR_FAIL_V(-1); } /** This will handle both Gzip and Deflate streams. It will automatically allocate the output buffer into the provided p_dst_vect Vector. This is required for compressed data whose final uncompressed size is unknown, as is the case for HTTP response bodies. This is much slower however than using Compression::decompress because it may result in multiple full copies of the output buffer. */ int Compression::decompress_dynamic(Vector<uint8_t> *p_dst_vect, int p_max_dst_size, const uint8_t *p_src, int p_src_size, Mode p_mode) { int ret; uint8_t *dst = nullptr; int out_mark = 0; z_stream strm; ERR_FAIL_COND_V(p_src_size <= 0, Z_DATA_ERROR); // This function only supports GZip and Deflate int window_bits = p_mode == MODE_DEFLATE ? 15 : 15 + 16; ERR_FAIL_COND_V(p_mode != MODE_DEFLATE && p_mode != MODE_GZIP, Z_ERRNO); // Initialize the stream strm.zalloc = Z_NULL; strm.zfree = Z_NULL; strm.opaque = Z_NULL; strm.avail_in = 0; strm.next_in = Z_NULL; int err = inflateInit2(&strm, window_bits); ERR_FAIL_COND_V(err != Z_OK, -1); // Setup the stream inputs strm.next_in = (Bytef *)p_src; strm.avail_in = p_src_size; // Ensure the destination buffer is empty p_dst_vect->resize(0); // decompress until deflate stream ends or end of file do { // Add another chunk size to the output buffer // This forces a copy of the whole buffer p_dst_vect->resize(p_dst_vect->size() + gzip_chunk); // Get pointer to the actual output buffer dst = p_dst_vect->ptrw(); // Set the stream to the new output stream // Since it was copied, we need to reset the stream to the new buffer strm.next_out = &(dst[out_mark]); strm.avail_out = gzip_chunk; // run inflate() on input until output buffer is full and needs to be resized // or input runs out do { ret = inflate(&strm, Z_SYNC_FLUSH); switch (ret) { case Z_NEED_DICT: ret = Z_DATA_ERROR; [[fallthrough]]; case Z_DATA_ERROR: case Z_MEM_ERROR: case Z_STREAM_ERROR: WARN_PRINT(strm.msg); (void)inflateEnd(&strm); p_dst_vect->resize(0); return ret; } } while (strm.avail_out > 0 && strm.avail_in > 0); out_mark += gzip_chunk; // Enforce max output size if (p_max_dst_size > -1 && strm.total_out > (uint64_t)p_max_dst_size) { (void)inflateEnd(&strm); p_dst_vect->resize(0); return Z_BUF_ERROR; } } while (ret != Z_STREAM_END); // If all done successfully, resize the output if it's larger than the actual output if ((unsigned long)p_dst_vect->size() > strm.total_out) { p_dst_vect->resize(strm.total_out); } // clean up and return (void)inflateEnd(&strm); return Z_OK; } int Compression::zlib_level = Z_DEFAULT_COMPRESSION; int Compression::gzip_level = Z_DEFAULT_COMPRESSION; int Compression::zstd_level = 3; bool Compression::zstd_long_distance_matching = false; int Compression::zstd_window_log_size = 27; // ZSTD_WINDOWLOG_LIMIT_DEFAULT int Compression::gzip_chunk = 16384;