This version of return_bytes takes care of the MB, GB, KB cases along with the M,G,K ones.
Hope this is helpful!
<?php
public static function return_bytes ($val)
{
if(empty($val))return 0;
$val = trim($val);
preg_match('#([0-9]+)[\s]*([a-z]+)#i', $val, $matches);
$last = '';
if(isset($matches[2])){
$last = $matches[2];
}
if(isset($matches[1])){
$val = (int) $matches[1];
}
switch (strtolower($last))
{
case 'g':
case 'gb':
$val *= 1024;
case 'm':
case 'mb':
$val *= 1024;
case 'k':
case 'kb':
$val *= 1024;
}
return (int) $val;
}
?>
ini_get
(PHP 4, PHP 5)
ini_get — Obtém o valor de uma opção de configuração
Descrição
Retorna o valor da opção em caso de sucesso. Em caso de falha, como tentar obter um valor que não exista, irá retornar uma string vazia.
Nota: Quando obtendo valores booleanos
Um valor booleano off será retornado como uma string vazia enquanto um valor booleano on será retornado como "1".
Nota: Quando obtendo valores de tamanho de memória
Vários valores de definição de tamanho de memória, como upload_max_filesize são guardados no arquivo php.ini em uma anotação curta. ini_get() irá retornar exatamente a string guardada no arquivo php.ini, NÃO o seu valor inteiro equivalente. Tentar funções matemáticas comuns com estes valores não trará o resultado esperado.
<?php
/*
Seu php.ini contém as seguintes definições:
display_errors = On
register_globals = Off
post_max_size = 8M
*/
echo 'display_errors = ' . ini_get('display_errors') . "\n";
echo 'register_globals = ' . ini_get('register_globals') . "\n";
echo 'post_max_size = ' . ini_get('post_max_size') . "\n";
echo 'post_max_size+1 = ' . (ini_get('post_max_size')+1) . "\n";
?>Este script irá produzir:
display_errors = 1 register_globals = 0 post_max_size = 8M post_max_size+1 = 9 */ ?>
Veja também get_cfg_var(), ini_get_all(), ini_restore() e ini_set().
another version of return_bytes which returns faster and does not use multiple multiplications (sorry:). even if it is resolved at compile time it is not a good practice;
no local variables are allocated;
the trim() is omitted (php already trimmed values when reading php.ini file);
strtolower() is replaced by second case which wins us one more function call for the price of doubling the number of cases to process (may slower the worst-case scenario when ariving to default: takes six comparisons instead of three comparisons and a function call);
cases are ordered by most frequent goes first (uppercase M-values being the default sizes);
specs say we must handle integer sizes so float values are converted to integers and 0.8G becomes 0;
'Gb', 'Mb', 'Kb' shorthand byte options are not implemented since are not in specs, see
http://www.php.net/manual/en/faq.using.php#faq.using.shorthandbytes
<?php
function return_bytes ($size_str)
{
switch (substr ($size_str, -1))
{
case 'M': case 'm': return (int)$size_str * 1048576;
case 'K': case 'k': return (int)$size_str * 1024;
case 'G': case 'g': return (int)$size_str * 1073741824;
default: return $size_str;
}
}
?>
Here is how to accurately test for boolean php.ini values:
<?php
function ini_get_bool($a)
{
$b = ini_get($a);
switch (strtolower($b))
{
case 'on':
case 'yes':
case 'true':
return 'assert.active' !== $a;
case 'stdout':
case 'stderr':
return 'display_errors' === $a;
default:
return (bool) (int) $b;
}
}
?>
Here's a simplified version of return_bytes() that does not rely on non-breaking cases and variable variables.
<?php
function return_bytes($val)
{
$val = trim($val);
$last = strtolower(substr($val, -1));
if($last == 'g')
$val = $val*1024*1024*1024;
if($last == 'm')
$val = $val*1024*1024;
if($last == 'k')
$val = $val*1024;
return $val;
}
?>
The above example function called return_bytes() assumes that ini_get('upload_max_filesize') delivers only one letter at the end. As I've seen 'Mb' and things like that, I'd suggest to change the $last = ... part into $last = strtolower(substr($val,strlen($val/1),1)).
I'd call it $unit then.
Concerning the value retourned, it depends on how you set it.
I had the problem with horde-3 which test the safe_mode value.
THan :
- if you set the value with php_admin_value safe_mode Off (or On) ini_get returns the string
- if you set the value with php_admin_flag safe_mode Off (or On) ini_get returns the boolean.
Important: The manual says that ini_get will return 0 or an empty string for boolean config values that are set to off in php.ini.
This is technically correct, however when you use
php_value register_globals off
in an .htaccess file, ini_get will return the string, which will "evaluate" to 1. So if you are using mod_php you have to check boolean config values against the strings (upper/lowercase etc.) anyhow or you will get wrong results.
You can set custom entries in the ini file to provide globals such as database details.
However these must be retrieved with get_cfg_var, ini_get won't work.
It might be useful for included scripts that include other files to extend the 'include_path' variable:
<?php ini_set('include_path',ini_get('include_path').':../includes:'); ?>
Sometimes, it may also be useful to store the current 'include_path' in a variable, overwrite it, include, and then restore the old 'include_path'.
If you want to test ini flags (eg. On/Off), I recommend to explicitly cast the value returned by ini_get() to boolean - it is cleaner as you only get true or false, not 0 or 1 or "" as described above.
<?php
$register_globals = (bool) ini_get('register_gobals');
?>
C fans may of course also cast it to (int) to play with 0 and 1 - that's also cleaner to print().
