lzo/src/lzo_ptr.c

   1 /* lzo_ptr.c -- low-level pointer constructs
   2
   3    This file is part of the LZO real-time data compression library.
   4
   5    Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
   6    Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
   7    Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
   8    Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
   9    Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
  10    Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
  11    Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
  12    Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
  13    Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
  14    Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
  15    Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
  16    Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
  17    Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
  18    All Rights Reserved.
  19
  20    The LZO library is free software; you can redistribute it and/or
  21    modify it under the terms of the GNU General Public License as
  22    published by the Free Software Foundation; either version 2 of
  23    the License, or (at your option) any later version.
  24
  25    The LZO library is distributed in the hope that it will be useful,
  26    but WITHOUT ANY WARRANTY; without even the implied warranty of
  27    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28    GNU General Public License for more details.
  29
  30    You should have received a copy of the GNU General Public License
  31    along with the LZO library; see the file COPYING.
  32    If not, write to the Free Software Foundation, Inc.,
  33    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  34
  35    Markus F.X.J. Oberhumer
  36    <markus@oberhumer.com>
  37    http://www.oberhumer.com/opensource/lzo/
  38  */
  39
  40
  41 #include "lzo_conf.h"
  42
  43
  44 /***********************************************************************
  45 //
  46 ************************************************************************/
  47
  48 LZO_PUBLIC(lzo_uintptr_t)
  49 __lzo_ptr_linear(const lzo_voidp ptr)
  50 {
  51     lzo_uintptr_t p;
  52
  53 #if (LZO_ARCH_I086)
  54     p = (((lzo_uintptr_t)(ACC_PTR_FP_SEG(ptr))) << (16 - ACC_MM_AHSHIFT)) + (ACC_PTR_FP_OFF(ptr));
  55 #elif (LZO_MM_PVP)
  56     p = (lzo_uintptr_t) (ptr);
  57     p = (p << 3) | (p >> 61);
  58 #else
  59     p = (lzo_uintptr_t) PTR_LINEAR(ptr);
  60 #endif
  61
  62     return p;
  63 }
  64
  65
  66 /***********************************************************************
  67 //
  68 ************************************************************************/
  69
  70 LZO_PUBLIC(unsigned)
  71 __lzo_align_gap(const lzo_voidp ptr, lzo_uint size)
  72 {
  73 #if defined(__LZO_UINTPTR_T_IS_POINTER)
  74     size_t n = (size_t) ptr;
  75     n = (((n + size - 1) / size) * size) - n;
  76 #else
  77     lzo_uintptr_t p, n;
  78     p = __lzo_ptr_linear(ptr);
  79     n = (((p + size - 1) / size) * size) - p;
  80 #endif
  81
  82     assert(size > 0);
  83     assert((long)n >= 0);
  84     assert(n <= size);
  85     return (unsigned)n;
  86 }
  87
  88
  89
  90 /*
  91 vi:ts=4:et
  92 */