/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
/* \file
* \brief Provides portable memory access primitives
*
* This function provides portable primitives for getting and setting of
* signed and unsigned integers in 16, 24, and 32 bit sizes. The operations
* can be performed on unaligned data regardless of hardware support for
* unaligned accesses.
*
* The type used to pass the integral values may be changed by defining
* MEM_VALUE_T with the appropriate type. The type given must be an integral
* numeric type.
*
* The actual functions instantiated have the MEM_VALUE_T type name pasted
* on to the symbol name. This allows the developer to instantiate these
* operations for multiple types within the same translation unit. This is
* of somewhat questionable utility, but the capability exists nonetheless.
* Users not making use of this functionality should call the functions
* without the type name appended, and the preprocessor will take care of
* it.
*
* NOTE: This code is not supported on platforms where char > 1 octet ATM.
*/
#ifndef MAU_T
/* Minimum Access Unit for this target */
#define MAU_T unsigned char
#endif
#ifndef MEM_VALUE_T
#define MEM_VALUE_T int
#endif
#undef MEM_VALUE_T_SZ_BITS
#define MEM_VALUE_T_SZ_BITS (sizeof(MEM_VALUE_T) << 3)
#undef mem_ops_wrap_symbol
#define mem_ops_wrap_symbol(fn) mem_ops_wrap_symbol2(fn, MEM_VALUE_T)
#undef mem_ops_wrap_symbol2
#define mem_ops_wrap_symbol2(fn,typ) mem_ops_wrap_symbol3(fn,typ)
#undef mem_ops_wrap_symbol3
#define mem_ops_wrap_symbol3(fn,typ) fn##_as_##typ
/*
* Include aligned access routines
*/
#define INCLUDED_BY_MEM_OPS_H
#include "mem_ops_aligned.h"
#undef INCLUDED_BY_MEM_OPS_H
#undef mem_get_be16
#define mem_get_be16 mem_ops_wrap_symbol(mem_get_be16)
static unsigned MEM_VALUE_T mem_get_be16(const void *vmem)
{
unsigned MEM_VALUE_T val;
const MAU_T *mem = (const MAU_T *)vmem;
val = mem[0] << 8;
val |= mem[1];
return val;
}
#undef mem_get_be24
#define mem_get_be24 mem_ops_wrap_symbol(mem_get_be24)
static unsigned MEM_VALUE_T mem_get_be24(const void *vmem)
{
unsigned MEM_VALUE_T val;
const MAU_T *mem = (const MAU_T *)vmem;
val = mem[0] << 16;
val |= mem[1] << 8;
val |= mem[2];
return val;
}
#undef mem_get_be32
#define mem_get_be32 mem_ops_wrap_symbol(mem_get_be32)
static unsigned MEM_VALUE_T mem_get_be32(const void *vmem)
{
unsigned MEM_VALUE_T val;
const MAU_T *mem = (const MAU_T *)vmem;
val = mem[0] << 24;
val |= mem[1] << 16;
val |= mem[2] << 8;
val |= mem[3];
return val;
}
#undef mem_get_le16
#define mem_get_le16 mem_ops_wrap_symbol(mem_get_le16)
static unsigned MEM_VALUE_T mem_get_le16(const void *vmem)
{
unsigned MEM_VALUE_T val;
const MAU_T *mem = (const MAU_T *)vmem;
val = mem[1] << 8;
val |= mem[0];
return val;
}
#undef mem_get_le24
#define mem_get_le24 mem_ops_wrap_symbol(mem_get_le24)
static unsigned MEM_VALUE_T mem_get_le24(const void *vmem)
{
unsigned MEM_VALUE_T val;
const MAU_T *mem = (const MAU_T *)vmem;
val = mem[2] << 16;
val |= mem[1] << 8;
val |= mem[0];
return val;
}
#undef mem_get_le32
#define mem_get_le32 mem_ops_wrap_symbol(mem_get_le32)
static unsigned MEM_VALUE_T mem_get_le32(const void *vmem)
{
unsigned MEM_VALUE_T val;
const MAU_T *mem = (const MAU_T *)vmem;
val = mem[3] << 24;
val |= mem[2] << 16;
val |= mem[1] << 8;
val |= mem[0];
return val;
}
#define mem_get_s_generic(end,sz) \
static signed MEM_VALUE_T mem_get_s##end##sz(const void *vmem) {\
const MAU_T *mem = (const MAU_T*)vmem;\
signed MEM_VALUE_T val = mem_get_##end##sz(mem);\
return (val << (MEM_VALUE_T_SZ_BITS - sz)) >> (MEM_VALUE_T_SZ_BITS - sz);\
}
#undef mem_get_sbe16
#define mem_get_sbe16 mem_ops_wrap_symbol(mem_get_sbe16)
mem_get_s_generic(be, 16);
#undef mem_get_sbe24
#define mem_get_sbe24 mem_ops_wrap_symbol(mem_get_sbe24)
mem_get_s_generic(be, 24);
#undef mem_get_sbe32
#define mem_get_sbe32 mem_ops_wrap_symbol(mem_get_sbe32)
mem_get_s_generic(be, 32);
#undef mem_get_sle16
#define mem_get_sle16 mem_ops_wrap_symbol(mem_get_sle16)
mem_get_s_generic(le, 16);
#undef mem_get_sle24
#define mem_get_sle24 mem_ops_wrap_symbol(mem_get_sle24)
mem_get_s_generic(le, 24);
#undef mem_get_sle32
#define mem_get_sle32 mem_ops_wrap_symbol(mem_get_sle32)
mem_get_s_generic(le, 32);
#undef mem_put_be16
#define mem_put_be16 mem_ops_wrap_symbol(mem_put_be16)
static void mem_put_be16(void *vmem, MEM_VALUE_T val)
{
MAU_T *mem = (MAU_T *)vmem;
mem[0] = (val >> 8) & 0xff;
mem[1] = (val >> 0) & 0xff;
}
#undef mem_put_be24
#define mem_put_be24 mem_ops_wrap_symbol(mem_put_be24)
static void mem_put_be24(void *vmem, MEM_VALUE_T val)
{
MAU_T *mem = (MAU_T *)vmem;
mem[0] = (val >> 16) & 0xff;
mem[1] = (val >> 8) & 0xff;
mem[2] = (val >> 0) & 0xff;
}
#undef mem_put_be32
#define mem_put_be32 mem_ops_wrap_symbol(mem_put_be32)
static void mem_put_be32(void *vmem, MEM_VALUE_T val)
{
MAU_T *mem = (MAU_T *)vmem;
mem[0] = (val >> 24) & 0xff;
mem[1] = (val >> 16) & 0xff;
mem[2] = (val >> 8) & 0xff;
mem[3] = (val >> 0) & 0xff;
}
#undef mem_put_le16
#define mem_put_le16 mem_ops_wrap_symbol(mem_put_le16)
static void mem_put_le16(void *vmem, MEM_VALUE_T val)
{
MAU_T *mem = (MAU_T *)vmem;
mem[0] = (val >> 0) & 0xff;
mem[1] = (val >> 8) & 0xff;
}
#undef mem_put_le24
#define mem_put_le24 mem_ops_wrap_symbol(mem_put_le24)
static void mem_put_le24(void *vmem, MEM_VALUE_T val)
{
MAU_T *mem = (MAU_T *)vmem;
mem[0] = (val >> 0) & 0xff;
mem[1] = (val >> 8) & 0xff;
mem[2] = (val >> 16) & 0xff;
}
#undef mem_put_le32
#define mem_put_le32 mem_ops_wrap_symbol(mem_put_le32)
static void mem_put_le32(void *vmem, MEM_VALUE_T val)
{
MAU_T *mem = (MAU_T *)vmem;
mem[0] = (val >> 0) & 0xff;
mem[1] = (val >> 8) & 0xff;
mem[2] = (val >> 16) & 0xff;
mem[3] = (val >> 24) & 0xff;
}