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glibc  2.9
a64l.c
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00001 /* Copyright (C) 1995, 1997, 1998, 1999 Free Software Foundation, Inc.
00002    This file is part of the GNU C Library.
00003    Contributed by Ulrich Drepper <drepper@gnu.org>, August 1995.
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 #include <stdlib.h>
00021 
00022 #define TABLE_BASE 0x2e
00023 #define TABLE_SIZE 0x4d
00024 
00025 #define XX ((char)0x40)
00026 
00027 
00028 static const char a64l_table[TABLE_SIZE] =
00029 {
00030   /* 0x2e */                                                           0,  1,
00031   /* 0x30 */   2,  3,  4,  5,  6,  7,  8,  9, 10, 11, XX, XX, XX, XX, XX, XX,
00032   /* 0x40 */  XX, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
00033   /* 0x50 */  27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, XX, XX, XX, XX, XX,
00034   /* 0x60 */  XX, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
00035   /* 0x70 */  53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63
00036 };
00037 
00038 
00039 long int
00040 a64l (string)
00041      const char *string;
00042 {
00043   const char *ptr = string;
00044   unsigned long int result = 0ul;
00045   const char *end = ptr + 6;
00046   int shift = 0;
00047 
00048   do
00049     {
00050       unsigned index;
00051       unsigned value;
00052 
00053       index = *ptr - TABLE_BASE;
00054       if ((unsigned int) index >= TABLE_SIZE)
00055        break;
00056       value = (int) a64l_table[index];
00057       if (value == (int) XX)
00058        break;
00059       ++ptr;
00060       result |= value << shift;
00061       shift += 6;
00062     }
00063   while (ptr != end);
00064 
00065   return (long int) result;
00066 }