mirror of
https://github.com/love2d/love.git
synced 2026-08-16 00:02:12 +02:00
Add love.data module.
- Moved love.math.compress / decompress / decode / encode / hash to love.data. - Changed love.data.compress/decompress to take the format argument first instead of second. - Added love.data.newDataView. Returns a read-only subsection of an existing Data object. - Added love.data.newByteData. Mostly useful in combination with LuaJIT's FFI as it has no extra methods currently. - Added implementations of Lua 5.3's data packing APIs: love.data.packString / packData / unpack / getPackedSize. Resolves issue #1336. Resolves issue #1331. --HG-- branch : minor
This commit is contained in:
Alex Szpakowski
@@ -0,0 +1,392 @@
|
||||
/**
|
||||
* Copyright (c) 2006-2017 LOVE Development Team
|
||||
*
|
||||
* This software is provided 'as-is', without any express or implied
|
||||
* warranty. In no event will the authors be held liable for any damages
|
||||
* arising from the use of this software.
|
||||
*
|
||||
* Permission is granted to anyone to use this software for any purpose,
|
||||
* including commercial applications, and to alter it and redistribute it
|
||||
* freely, subject to the following restrictions:
|
||||
*
|
||||
* 1. The origin of this software must not be misrepresented; you must not
|
||||
* claim that you wrote the original software. If you use this software
|
||||
* in a product, an acknowledgment in the product documentation would be
|
||||
* appreciated but is not required.
|
||||
* 2. Altered source versions must be plainly marked as such, and must not be
|
||||
* misrepresented as being the original software.
|
||||
* 3. This notice may not be removed or altered from any source distribution.
|
||||
**/
|
||||
|
||||
// LOVE
|
||||
#include "Compressor.h"
|
||||
#include "common/config.h"
|
||||
#include "common/int.h"
|
||||
|
||||
#include "libraries/lz4/lz4.h"
|
||||
#include "libraries/lz4/lz4hc.h"
|
||||
|
||||
#include <zlib.h>
|
||||
|
||||
namespace love
|
||||
{
|
||||
namespace data
|
||||
{
|
||||
|
||||
class LZ4Compressor : public Compressor
|
||||
{
|
||||
public:
|
||||
|
||||
char *compress(Format format, const char *data, size_t dataSize, int level, size_t &compressedSize) override
|
||||
{
|
||||
if (format != FORMAT_LZ4)
|
||||
throw love::Exception("Invalid format (expecting LZ4)");
|
||||
|
||||
if (dataSize > LZ4_MAX_INPUT_SIZE)
|
||||
throw love::Exception("Data is too large for LZ4 compressor.");
|
||||
|
||||
// We use a custom header to store some info with the compressed data.
|
||||
const size_t headersize = sizeof(uint32);
|
||||
|
||||
int maxdestsize = LZ4_compressBound((int) dataSize);
|
||||
size_t maxsize = headersize + (size_t) maxdestsize;
|
||||
char *compressedbytes = nullptr;
|
||||
|
||||
try
|
||||
{
|
||||
compressedbytes = new char[maxsize];
|
||||
}
|
||||
catch (std::bad_alloc &)
|
||||
{
|
||||
throw love::Exception("Out of memory.");
|
||||
}
|
||||
|
||||
// Store the size of the uncompressed data as a header.
|
||||
#ifdef LOVE_BIG_ENDIAN
|
||||
// Make sure it's little-endian for storage.
|
||||
*(uint32 *) compressedbytes = swapuint32((uint32) dataSize);
|
||||
#else
|
||||
*(uint32 *) compressedbytes = (uint32) dataSize;
|
||||
#endif
|
||||
|
||||
// Use LZ4-HC for compression level 9 and higher.
|
||||
int csize = 0;
|
||||
if (level > 8)
|
||||
csize = LZ4_compress_HC(data, compressedbytes + headersize, (int) dataSize, maxdestsize, 0);
|
||||
else
|
||||
csize = LZ4_compress_default(data, compressedbytes + headersize, (int) dataSize, maxdestsize);
|
||||
|
||||
if (csize <= 0)
|
||||
{
|
||||
delete[] compressedbytes;
|
||||
throw love::Exception("Could not LZ4-compress data.");
|
||||
}
|
||||
|
||||
// We allocated space for the maximum possible amount of data, but the
|
||||
// actual compressed size might be much smaller, so we should shrink the
|
||||
// data buffer if so.
|
||||
if ((double) maxsize / (double) (csize + headersize) >= 1.2)
|
||||
{
|
||||
char *cbytes = new (std::nothrow) char[csize + headersize];
|
||||
if (cbytes)
|
||||
{
|
||||
memcpy(cbytes, compressedbytes, csize + headersize);
|
||||
delete[] compressedbytes;
|
||||
compressedbytes = cbytes;
|
||||
}
|
||||
}
|
||||
|
||||
compressedSize = (size_t) csize + headersize;
|
||||
return compressedbytes;
|
||||
}
|
||||
|
||||
char *decompress(Format format, const char *data, size_t dataSize, size_t &decompressedSize) override
|
||||
{
|
||||
if (format != FORMAT_LZ4)
|
||||
throw love::Exception("Invalid format (expecting LZ4)");
|
||||
|
||||
const size_t headersize = sizeof(uint32);
|
||||
char *rawbytes = nullptr;
|
||||
|
||||
if (dataSize < headersize)
|
||||
throw love::Exception("Invalid LZ4-compressed data size.");
|
||||
|
||||
// Extract the original uncompressed size (stored in our custom header.)
|
||||
#ifdef LOVE_BIG_ENDIAN
|
||||
// Convert from stored little-endian to big-endian.
|
||||
uint32 rawsize = swapuint32(*(uint32 *) data);
|
||||
#else
|
||||
uint32 rawsize = *(uint32 *) data;
|
||||
#endif
|
||||
|
||||
try
|
||||
{
|
||||
rawbytes = new char[rawsize];
|
||||
}
|
||||
catch (std::bad_alloc &)
|
||||
{
|
||||
throw love::Exception("Out of memory.");
|
||||
}
|
||||
|
||||
// If the uncompressed size is passed in as an argument (non-zero) and
|
||||
// it matches the header's stored size, then we assume it's 100% accurate
|
||||
// and we use a more efficient decompression function.
|
||||
if (decompressedSize > 0 && decompressedSize == (size_t) rawsize)
|
||||
{
|
||||
// We don't use the header here, but we need to account for its size.
|
||||
if (LZ4_decompress_fast(data + headersize, rawbytes, (int) decompressedSize) < 0)
|
||||
{
|
||||
delete[] rawbytes;
|
||||
throw love::Exception("Could not decompress LZ4-compressed data.");
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
// Account for our custom header's size in the decompress arguments.
|
||||
int result = LZ4_decompress_safe(data + headersize, rawbytes,
|
||||
(int) (dataSize - headersize), rawsize);
|
||||
|
||||
if (result < 0)
|
||||
{
|
||||
delete[] rawbytes;
|
||||
throw love::Exception("Could not decompress LZ4-compressed data.");
|
||||
}
|
||||
|
||||
decompressedSize = (size_t) result;
|
||||
}
|
||||
|
||||
return rawbytes;
|
||||
}
|
||||
|
||||
bool isSupported(Format format) const override
|
||||
{
|
||||
return format == FORMAT_LZ4;
|
||||
}
|
||||
|
||||
}; // LZ4Compressor
|
||||
|
||||
|
||||
class zlibCompressor : public Compressor
|
||||
{
|
||||
private:
|
||||
|
||||
// The following three functions are mostly copied from the zlib source
|
||||
// (compressBound, compress2, and uncompress), but modified to support both
|
||||
// zlib and gzip.
|
||||
|
||||
uLong zlibCompressBound(Format format, uLong sourceLen)
|
||||
{
|
||||
uLong size = sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + (sourceLen >> 25) + 13;
|
||||
|
||||
// The gzip header is slightly larger than the zlib header.
|
||||
if (format == FORMAT_GZIP)
|
||||
size += 18 - 6;
|
||||
|
||||
return size;
|
||||
}
|
||||
|
||||
int zlibCompress(Format format, Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen, int level)
|
||||
{
|
||||
z_stream stream = {};
|
||||
|
||||
stream.next_in = (Bytef *) source;
|
||||
stream.avail_in = (uInt) sourceLen;
|
||||
|
||||
stream.next_out = dest;
|
||||
stream.avail_out = (uInt) (*destLen);
|
||||
|
||||
int windowbits = 15;
|
||||
if (format == FORMAT_GZIP)
|
||||
windowbits += 16; // This tells zlib to use a gzip header.
|
||||
|
||||
int err = deflateInit2(&stream, level, Z_DEFLATED, windowbits, 8, Z_DEFAULT_STRATEGY);
|
||||
|
||||
if (err != Z_OK)
|
||||
return err;
|
||||
|
||||
err = deflate(&stream, Z_FINISH);
|
||||
|
||||
if (err != Z_STREAM_END)
|
||||
{
|
||||
deflateEnd(&stream);
|
||||
return err == Z_OK ? Z_BUF_ERROR : err;
|
||||
}
|
||||
|
||||
*destLen = stream.total_out;
|
||||
|
||||
return deflateEnd(&stream);
|
||||
}
|
||||
|
||||
int zlibDecompress(Bytef *dest, uLongf *destLen, const Bytef *source, uLong sourceLen)
|
||||
{
|
||||
z_stream stream = {};
|
||||
|
||||
stream.next_in = (Bytef *) source;
|
||||
stream.avail_in = (uInt) sourceLen;
|
||||
|
||||
stream.next_out = dest;
|
||||
stream.avail_out = (uInt) (*destLen);
|
||||
|
||||
// 15 is the default. Adding 32 makes zlib auto-detect the header type.
|
||||
int windowbits = 15 + 32;
|
||||
|
||||
int err = inflateInit2(&stream, windowbits);
|
||||
|
||||
if (err != Z_OK)
|
||||
return err;
|
||||
|
||||
err = inflate(&stream, Z_FINISH);
|
||||
|
||||
if (err != Z_STREAM_END)
|
||||
{
|
||||
inflateEnd(&stream);
|
||||
if (err == Z_NEED_DICT || (err == Z_BUF_ERROR && stream.avail_in == 0))
|
||||
return Z_DATA_ERROR;
|
||||
return err;
|
||||
}
|
||||
|
||||
*destLen = stream.total_out;
|
||||
|
||||
return inflateEnd(&stream);
|
||||
}
|
||||
|
||||
public:
|
||||
|
||||
char *compress(Format format, const char *data, size_t dataSize, int level, size_t &compressedSize) override
|
||||
{
|
||||
if (!isSupported(format))
|
||||
throw love::Exception("Invalid format (expecting zlib or gzip)");
|
||||
|
||||
if (level < 0)
|
||||
level = Z_DEFAULT_COMPRESSION;
|
||||
else if (level > 9)
|
||||
level = 9;
|
||||
|
||||
uLong maxsize = zlibCompressBound(format, (uLong) dataSize);
|
||||
char *compressedbytes = nullptr;
|
||||
|
||||
try
|
||||
{
|
||||
compressedbytes = new char[maxsize];
|
||||
}
|
||||
catch (std::bad_alloc &)
|
||||
{
|
||||
throw love::Exception("Out of memory.");
|
||||
}
|
||||
|
||||
uLongf destlen = maxsize;
|
||||
int status = zlibCompress(format, (Bytef *) compressedbytes, &destlen, (const Bytef *) data, (uLong) dataSize, level);
|
||||
|
||||
if (status != Z_OK)
|
||||
{
|
||||
delete[] compressedbytes;
|
||||
throw love::Exception("Could not zlib/gzip-compress data.");
|
||||
}
|
||||
|
||||
// We allocated space for the maximum possible amount of data, but the
|
||||
// actual compressed size might be much smaller, so we should shrink the
|
||||
// data buffer if so.
|
||||
if ((double) maxsize / (double) destlen >= 1.3)
|
||||
{
|
||||
char *cbytes = new (std::nothrow) char[destlen];
|
||||
if (cbytes)
|
||||
{
|
||||
memcpy(cbytes, compressedbytes, destlen);
|
||||
delete[] compressedbytes;
|
||||
compressedbytes = cbytes;
|
||||
}
|
||||
}
|
||||
|
||||
compressedSize = (size_t) destlen;
|
||||
return compressedbytes;
|
||||
}
|
||||
|
||||
char *decompress(Format format, const char *data, size_t dataSize, size_t &decompressedSize) override
|
||||
{
|
||||
if (!isSupported(format))
|
||||
throw love::Exception("Invalid format (expecting zlib or gzip)");
|
||||
|
||||
char *rawbytes = nullptr;
|
||||
|
||||
// We might know the output size before decompression. If not, we guess.
|
||||
size_t rawsize = decompressedSize > 0 ? decompressedSize : dataSize * 2;
|
||||
|
||||
// Repeatedly try to decompress with an increasingly large output buffer.
|
||||
while (true)
|
||||
{
|
||||
try
|
||||
{
|
||||
rawbytes = new char[rawsize];
|
||||
}
|
||||
catch (std::bad_alloc &)
|
||||
{
|
||||
throw love::Exception("Out of memory.");
|
||||
}
|
||||
|
||||
uLongf destLen = (uLongf) rawsize;
|
||||
int status = zlibDecompress((Bytef *) rawbytes, &destLen, (const Bytef *) data, (uLong) dataSize);
|
||||
|
||||
if (status == Z_OK)
|
||||
{
|
||||
decompressedSize = (size_t) destLen;
|
||||
break;
|
||||
}
|
||||
else if (status != Z_BUF_ERROR)
|
||||
{
|
||||
// For any error other than "not enough room", throw an exception.
|
||||
delete[] rawbytes;
|
||||
throw love::Exception("Could not decompress zlib/gzip-compressed data.");
|
||||
}
|
||||
|
||||
// Not enough room in the output buffer: try again with a larger size.
|
||||
delete[] rawbytes;
|
||||
rawsize *= 2;
|
||||
}
|
||||
|
||||
return rawbytes;
|
||||
}
|
||||
|
||||
bool isSupported(Format format) const override
|
||||
{
|
||||
return format == FORMAT_ZLIB || format == FORMAT_GZIP;
|
||||
}
|
||||
|
||||
}; // zlibCompressor
|
||||
|
||||
Compressor *Compressor::getCompressor(Format format)
|
||||
{
|
||||
static LZ4Compressor lz4compressor;
|
||||
static zlibCompressor zlibcompressor;
|
||||
|
||||
Compressor *compressors[] = {&lz4compressor, &zlibcompressor};
|
||||
|
||||
for (Compressor *c : compressors)
|
||||
{
|
||||
if (c->isSupported(format))
|
||||
return c;
|
||||
}
|
||||
|
||||
return nullptr;
|
||||
}
|
||||
|
||||
bool Compressor::getConstant(const char *in, Format &out)
|
||||
{
|
||||
return formatNames.find(in, out);
|
||||
}
|
||||
|
||||
bool Compressor::getConstant(Format in, const char *&out)
|
||||
{
|
||||
return formatNames.find(in, out);
|
||||
}
|
||||
|
||||
StringMap<Compressor::Format, Compressor::FORMAT_MAX_ENUM>::Entry Compressor::formatEntries[] =
|
||||
{
|
||||
{ "lz4", FORMAT_LZ4 },
|
||||
{ "zlib", FORMAT_ZLIB },
|
||||
{ "gzip", FORMAT_GZIP },
|
||||
};
|
||||
|
||||
StringMap<Compressor::Format, Compressor::FORMAT_MAX_ENUM> Compressor::formatNames(Compressor::formatEntries, sizeof(Compressor::formatEntries));
|
||||
|
||||
} // data
|
||||
} // love
|
||||
Reference in New Issue
Block a user