Oops !!! I've left old license header. Here is smaller clean version that apply to CVS HEAD.

Wouldn't it be more practical to implement these as stream filters?

Ron

"Wojtek Meler" wmeler@wp.pl schreef in bericht
news:431C2738.2040602@wp.pl...

I've patched original crc32 PHP function to allow incremental crc32
counting.
It touches only a few lines of original code.
New crc32 function signature is

int crc32(string str [,int prev_sum])

With this patch you can generate crc32 checksum for even large files
without reading it contents to single variable.
Fe. instead of doing

| $file_string = file_get_contents($file);
$crc = crc32($file_string);
|
you can do

$crc=0;
$f =fopen($file,'r');
while ( $data=fread($f,1024)) $crc = crc32($data,$crc);
fclose($f);

Icremental processing has less memory requirements.
I'd like also change base64_* functions to allow incremental processing.

Any chances apply such changes ?

Regards,
Wojtek

Index: crc32.c

RCS file: /repository/php-src/ext/standard/crc32.c,v
retrieving revision 1.16
diff -u -r1.16 crc32.c
--- crc32.c 3 Aug 2005 14:07:57 -0000 1.16
+++ crc32.c 5 Sep 2005 11:02:00 -0000
@@ -1,13 +1,13 @@
/*

+----------------------------------------------------------------------+

• | PHP Version 5
  |

• | PHP Version 4
  |

+----------------------------------------------------------------------+

• | Copyright (c) 1997-2005 The PHP Group
  |

• | Copyright (c) 1997-2003 The PHP Group
  |

+----------------------------------------------------------------------+

• | This source file is subject to version 3.0 of the PHP license,
  |

• | This source file is subject to version 2.02 of the PHP license,
  |
  | that is bundled with this package in the file LICENSE, and is
  |

• | available through the world-wide-web at the following url:
  |
• | http://www.php.net/license/3_0.txt.
  |

• | available at through the world-wide-web at
  |
• | http://www.php.net/license/2_02.txt.
  |
  | If you did not receive a copy of the PHP license and are unable to
  |
  | obtain it through the world-wide-web, please send a note to
  |
  | license@php.net so we can mail you a copy immediately.
  |
  @@ -22,20 +22,19 @@
  #include "basic_functions.h"
  #include "crc32.h"

-/* {{{ proto string crc32(string str)
+/* {{{ proto int crc32(string str[,int prev_crc])
Calculate the crc32 polynomial of a string */
PHP_NAMED_FUNCTION(php_if_crc32)
{

• unsigned int crc = ~0;

• unsigned int crc = 0;
  char *p;

• int len, nr;

• int len;

• if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &p, &nr) ==
  FAILURE) {

• if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|l", &p, &len,
  &crc) == FAILURE) {
  return;
  }

• len = 0 ;
• for (len += nr; nr--; ++p) {

• crc = ~crc;
• for (; len--; ++p) {
  CRC32(crc, *p);
  }
  RETVAL_LONG(~crc);