note 86239 added to function.sha1
| From: | AndreD at osu1 dot php dot net | Date: | Thu, 09 Oct 2008 01:28:32 +0000 |
| Subject: | note 86239 added to function.sha1 | ||
| Groups: | php.notes | ||
| Request: | Send a blank email to php-notes+get-145197@lists.php.net to get a copy of this message | ||
Here's a better version of the getDigestNotation() function I posted earlier. (The first
version had a bug in the argument checking.)
<?php
function getDigestNotation($rawDigest, $bitsPerCharacter, $chars = NULL)
{
if ($chars === NULL || strlen($chars) < 2) {
$chars = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-,';
}
if ($bitsPerCharacter < 1) {
// $bitsPerCharacter must be at least 1
$bitsPerCharacter = 1;
} elseif (strlen($chars) < pow(2, $bitsPerCharacter)) {
// Character length of $chars is too small for $bitsPerCharacter
// Set $bitsPerCharacter to greatest value allowed by length of $chars
$bitsPerCharacter = 1;
$minCharLength = 2;
while (strlen($chars) >= ($minCharLength *= 2)) {
$bitsPerCharacter++;
}
unset($minCharLength);
}
$bytes = unpack('C*', $rawDigest);
$byteCount = count($bytes);
$out = '';
$byte = array_shift($bytes);
$bitsRead = 0;
for ($i = 0; $i < $byteCount * 8 / $bitsPerCharacter; $i++) {
if ($bitsRead + $bitsPerCharacter > 8) {
// Not enough bits remain in this byte for the current character
// Get remaining bits and get next byte
$oldBits = $byte - ($byte >> 8 - $bitsRead << 8 - $bitsRead);
if (count($bytes) == 0) {
// Last bits; match final character and exit loop
$out .= $chars[$oldBits];
break;
}
$oldBitCount = 8 - $bitsRead;
$byte = array_shift($bytes);
$bitsRead = 0;
} else {
$oldBitCount = 0;
}
// Read only the needed bits from this byte
$bits = $byte >> 8 - ($bitsRead + ($bitsPerCharacter - $oldBitCount));
$bits = $bits - ($bits >> $bitsPerCharacter - $oldBitCount << $bitsPerCharacter
- $oldBitCount);
$bitsRead += $bitsPerCharacter - $oldBitCount;
if ($oldBitCount > 0) {
// Bits come from seperate bytes, add $oldBits to $bits
$bits = ($oldBits << $bitsPerCharacter - $oldBitCount) | $bits;
}
$out .= $chars[$bits];
}
return $out;
}
?>
----
Server IP: 208.69.120.35
Probable Submitter: 207.88.114.211
----
Manual Page -- http://www.php.net/manual/en/function.sha1.php
Edit -- https://master.php.net/note/edit/86239
Del: integrated -- https://master.php.net/note/delete/86239/integrated
Del: useless -- https://master.php.net/note/delete/86239/useless
Del: bad code -- https://master.php.net/note/delete/86239/bad+code
Del: spam -- https://master.php.net/note/delete/86239/spam
Del: non-english -- https://master.php.net/note/delete/86239/non-english
Del: in docs -- https://master.php.net/note/delete/86239/in+docs
Del: other reasons-- https://master.php.net/note/delete/86239
Reject -- https://master.php.net/note/reject/86239
Search -- https://master.php.net/manage/user-notes.php