harfbuzz/src/graphite2/src/inc/Compression.h

82 lines
1.4 KiB
C++

// SPDX-License-Identifier: MIT
// Copyright 2015, SIL International, All rights reserved.
#pragma once
#include <cassert>
#include <cstddef>
#include <cstring>
namespace
{
#if defined(_MSC_VER)
typedef unsigned __int8 u8;
typedef unsigned __int16 u16;
typedef unsigned __int32 u32;
typedef unsigned __int64 u64;
#else
#include <stdint.h>
typedef uint8_t u8;
typedef uint16_t u16;
typedef uint32_t u32;
typedef uint64_t u64;
#endif
ptrdiff_t const MINMATCH = 4,
LASTLITERALS = 5,
MINCODA = LASTLITERALS+1,
MINSRCSIZE = 13;
template<int S>
inline
void unaligned_copy(void * d, void const * s) {
::memcpy(d, s, S);
}
inline
size_t align(size_t p) {
return (p + sizeof(unsigned long)-1) & ~(sizeof(unsigned long)-1);
}
inline
u8 * safe_copy(u8 * d, u8 const * s, size_t n) {
while (n--) *d++ = *s++;
return d;
}
inline
u8 * overrun_copy(u8 * d, u8 const * s, size_t n) {
size_t const WS = sizeof(unsigned long);
u8 const * e = s + n;
do
{
unaligned_copy<WS>(d, s);
d += WS;
s += WS;
}
while (s < e);
d-=(s-e);
return d;
}
inline
u8 * fast_copy(u8 * d, u8 const * s, size_t n) {
size_t const WS = sizeof(unsigned long);
size_t wn = n/WS;
while (wn--)
{
unaligned_copy<WS>(d, s);
d += WS;
s += WS;
}
n &= WS-1;
return safe_copy(d, s, n);
}
} // end of anonymous namespace