crc32.c 1.8 KB

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  1. /*
  2. +----------------------------------------------------------------------+
  3. | PHP Version 5 |
  4. +----------------------------------------------------------------------+
  5. | Copyright (c) 1997-2016 The PHP Group |
  6. +----------------------------------------------------------------------+
  7. | This source file is subject to version 3.01 of the PHP license, |
  8. | that is bundled with this package in the file LICENSE, and is |
  9. | available through the world-wide-web at the following url: |
  10. | http://www.php.net/license/3_01.txt |
  11. | If you did not receive a copy of the PHP license and are unable to |
  12. | obtain it through the world-wide-web, please send a note to |
  13. | license@php.net so we can mail you a copy immediately. |
  14. +----------------------------------------------------------------------+
  15. | Author: Rasmus Lerdorf <rasmus@php.net> |
  16. +----------------------------------------------------------------------+
  17. */
  18. /* $Id$ */
  19. #include "php.h"
  20. #include "basic_functions.h"
  21. #include "crc32.h"
  22. /* {{{ proto string crc32(string str)
  23. Calculate the crc32 polynomial of a string */
  24. PHP_NAMED_FUNCTION(php_if_crc32)
  25. {
  26. char *p;
  27. int len, nr;
  28. php_uint32 crcinit = 0;
  29. register php_uint32 crc;
  30. if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &p, &nr) == FAILURE) {
  31. return;
  32. }
  33. crc = crcinit^0xFFFFFFFF;
  34. for (len =+nr; nr--; ++p) {
  35. crc = ((crc >> 8) & 0x00FFFFFF) ^ crc32tab[(crc ^ (*p)) & 0xFF ];
  36. }
  37. RETVAL_LONG(crc^0xFFFFFFFF);
  38. }
  39. /* }}} */
  40. /*
  41. * Local variables:
  42. * tab-width: 4
  43. * c-basic-offset: 4
  44. * End:
  45. * vim600: sw=4 ts=4 fdm=marker
  46. * vim<600: sw=4 ts=4
  47. */