a64l.c 1.9 KB

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  1. /* Copyright (C) 1995, 1997, 1998, 1999 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Ulrich Drepper <drepper@gnu.org>, August 1995.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. #include <stdlib.h>
  16. #define TABLE_BASE 0x2e
  17. #define TABLE_SIZE 0x4d
  18. #define XX ((char)0x40)
  19. static const char a64l_table[TABLE_SIZE] =
  20. {
  21. /* 0x2e */ 0, 1,
  22. /* 0x30 */ 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, XX, XX, XX, XX, XX, XX,
  23. /* 0x40 */ XX, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
  24. /* 0x50 */ 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, XX, XX, XX, XX, XX,
  25. /* 0x60 */ XX, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
  26. /* 0x70 */ 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63
  27. };
  28. long int a64l (const char *string)
  29. {
  30. const char *ptr = string;
  31. unsigned long int result = 0ul;
  32. const char *end = ptr + 6;
  33. int shift = 0;
  34. do
  35. {
  36. unsigned index;
  37. unsigned value;
  38. index = *ptr - TABLE_BASE;
  39. if ((unsigned int) index >= TABLE_SIZE)
  40. break;
  41. value = (int) a64l_table[index];
  42. if (value == (int) XX)
  43. break;
  44. ++ptr;
  45. result |= value << shift;
  46. shift += 6;
  47. }
  48. while (ptr != end);
  49. return (long int) result;
  50. }