lzo/src/lzo_init.c

   1 /* lzo_init.c -- initialization of the LZO library
   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 // Runtime check of the assumptions about the size of builtin types,
  46 // memory model, byte order and other low-level constructs.
  47 //
  48 // We are really paranoid here - LZO should either fail
  49 // at startup or not at all.
  50 //
  51 // Because of inlining much of these functions evaluates to nothing.
  52 //
  53 // And while many of the tests seem highly obvious and redundant they are
  54 // here to catch compiler/optimizer bugs. Yes, these do exist.
  55 ************************************************************************/
  56
  57 #if !defined(__LZO_IN_MINILZO)
  58
  59 #define ACC_WANT_ACC_CHK_CH 1
  60 #undef ACCCHK_ASSERT
  61 #include "miniacc.h"
  62
  63     ACCCHK_ASSERT_IS_SIGNED_T(lzo_int)
  64     ACCCHK_ASSERT_IS_UNSIGNED_T(lzo_uint)
  65
  66     ACCCHK_ASSERT_IS_SIGNED_T(lzo_int32)
  67     ACCCHK_ASSERT_IS_UNSIGNED_T(lzo_uint32)
  68     ACCCHK_ASSERT((LZO_UINT32_C(1) << (int)(8*sizeof(LZO_UINT32_C(1))-1)) > 0)
  69     ACCCHK_ASSERT(sizeof(lzo_uint32) >= 4)
  70
  71 #if !defined(__LZO_UINTPTR_T_IS_POINTER)
  72     ACCCHK_ASSERT_IS_UNSIGNED_T(lzo_uintptr_t)
  73 #endif
  74     ACCCHK_ASSERT(sizeof(lzo_uintptr_t) >= sizeof(lzo_voidp))
  75
  76     ACCCHK_ASSERT_IS_UNSIGNED_T(lzo_xint)
  77     ACCCHK_ASSERT(sizeof(lzo_xint) >= sizeof(lzo_uint32))
  78     ACCCHK_ASSERT(sizeof(lzo_xint) >= sizeof(lzo_uint))
  79     ACCCHK_ASSERT(sizeof(lzo_xint) == sizeof(lzo_uint32) || sizeof(lzo_xint) == sizeof(lzo_uint))
  80
  81 #endif
  82 #undef ACCCHK_ASSERT
  83
  84
  85 /***********************************************************************
  86 //
  87 ************************************************************************/
  88
  89 LZO_PUBLIC(int)
  90 _lzo_config_check(void)
  91 {
  92     lzo_bool r = 1;
  93     union { unsigned char c[2*sizeof(lzo_xint)]; lzo_xint l[2]; } u;
  94     lzo_uintptr_t p;
  95
  96 #if !defined(LZO_CFG_NO_CONFIG_CHECK)
  97 #if defined(LZO_ABI_BIG_ENDIAN)
  98     u.l[0] = u.l[1] = 0; u.c[sizeof(lzo_xint) - 1] = 128;
  99     r &= (u.l[0] == 128);
 100 #endif
 101 #if defined(LZO_ABI_LITTLE_ENDIAN)
 102     u.l[0] = u.l[1] = 0; u.c[0] = 128;
 103     r &= (u.l[0] == 128);
 104 #endif
 105 #if defined(LZO_UNALIGNED_OK_2)
 106     p = (lzo_uintptr_t) (const lzo_voidp) &u.c[0];
 107     u.l[0] = u.l[1] = 0;
 108     r &= ((* (const lzo_ushortp) (p+1)) == 0);
 109 #endif
 110 #if defined(LZO_UNALIGNED_OK_4)
 111     p = (lzo_uintptr_t) (const lzo_voidp) &u.c[0];
 112     u.l[0] = u.l[1] = 0;
 113     r &= ((* (const lzo_uint32p) (p+1)) == 0);
 114 #endif
 115 #endif
 116
 117     LZO_UNUSED(u); LZO_UNUSED(p);
 118     return r == 1 ? LZO_E_OK : LZO_E_ERROR;
 119 }
 120
 121
 122 /***********************************************************************
 123 //
 124 ************************************************************************/
 125
 126 int __lzo_init_done = 0;
 127
 128 LZO_PUBLIC(int)
 129 __lzo_init_v2(unsigned v, int s1, int s2, int s3, int s4, int s5,
 130                           int s6, int s7, int s8, int s9)
 131 {
 132     int r;
 133
 134 #if defined(__LZO_IN_MINILZO)
 135 #elif (LZO_CC_MSC && ((_MSC_VER) < 700))
 136 #else
 137 #define ACC_WANT_ACC_CHK_CH 1
 138 #undef ACCCHK_ASSERT
 139 #define ACCCHK_ASSERT(expr)  LZO_COMPILE_TIME_ASSERT(expr)
 140 #include "miniacc.h"
 141 #endif
 142 #undef ACCCHK_ASSERT
 143
 144     __lzo_init_done = 1;
 145
 146     if (v == 0)
 147         return LZO_E_ERROR;
 148
 149     r = (s1 == -1 || s1 == (int) sizeof(short)) &&
 150         (s2 == -1 || s2 == (int) sizeof(int)) &&
 151         (s3 == -1 || s3 == (int) sizeof(long)) &&
 152         (s4 == -1 || s4 == (int) sizeof(lzo_uint32)) &&
 153         (s5 == -1 || s5 == (int) sizeof(lzo_uint)) &&
 154         (s6 == -1 || s6 == (int) lzo_sizeof_dict_t) &&
 155         (s7 == -1 || s7 == (int) sizeof(char *)) &&
 156         (s8 == -1 || s8 == (int) sizeof(lzo_voidp)) &&
 157         (s9 == -1 || s9 == (int) sizeof(lzo_callback_t));
 158     if (!r)
 159         return LZO_E_ERROR;
 160
 161     r = _lzo_config_check();
 162     if (r != LZO_E_OK)
 163         return r;
 164
 165     return r;
 166 }
 167
 168
 169 #if !defined(__LZO_IN_MINILZO)
 170 #include "lzo_dll.ch"
 171 #endif
 172
 173
 174 /*
 175 vi:ts=4:et
 176 */