The Tor Browser: media/libvpx/vpx_ports/mem_ops.h@ac0c01689b40 (annotated)

media/libvpx/vpx_ports/mem_ops.h@ac0c01689b40 (annotated)

media/libvpx/vpx_ports/mem_ops.h

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /*
  *  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;
 }

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media/libvpx/vpx_ports/mem_ops.h@ac0c01689b40 (annotated)

media/libvpx/vpx_ports/mem_ops.h