Ok, so basically I'm working on a project where I need to stream MP4 videos from a hidden source.
As most of people in this forum with this problem, I've used a solution derived from: http://mobiforge.com/developing/story/content-delivery-mobile-devices
function get_video($file){
$fp = @fopen($file, 'rb');
$size = filesize($file); // File size
$length = $size; // Content length
$start = 0; // Start byte
$end = $size - 1; // End byte
header('Content-type: video/mp4');
header("Accept-Ranges: 0-$length");
if (isset($_SERVER['HTTP_RANGE'])) {
$c_start = $start;
$c_end = $end;
list(, $range) = explode('=', $_SERVER['HTTP_RANGE'], 2);
if (strpos($range, ',') !== false) {
header('HTTP/1.1 416 Requested Range Not Satisfiable');
header("Content-Range: bytes $start-$end/$size");
exit;
}
if ($range == '-') {
$c_start = $size - substr($range, 1);
}else{
$range = explode('-', $range);
$c_start = $range[0];
$c_end = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $size;
}
$c_end = ($c_end > $end) ? $end : $c_end;
if ($c_start > $c_end || $c_start > $size - 1 || $c_end >= $size) {
header('HTTP/1.1 416 Requested Range Not Satisfiable');
header("Content-Range: bytes $start-$end/$size");
exit;
}
$start = $c_start;
$end = $c_end;
$length = $end - $start + 1;
fseek($fp, $start);
header('HTTP/1.1 206 Partial Content');
}
header("Content-Range: bytes $start-$end/$size");
header("Content-Length: ".$length);
$buffer = 1024 * 8;
while(!feof($fp) && ($p = ftell($fp)) <= $end) {
if ($p + $buffer > $end) {
$buffer = $end - $p + 1;
}
set_time_limit(0);
echo fread($fp, $buffer);
flush();
}
fclose($fp);
}
The problem appears when you are trying to process a video file bigger than 2GB (in a x86 machine).
The first problem I found was with the php filesize() function, which gives a negative value when the file is bigger than 2GB. For this issue I'm using a work around which is working correctly:
function showsize($file) {
if (strtoupper(substr(PHP_OS, 0, 3)) == 'WIN') {
if (class_exists("COM")) {
$fsobj = new COM('Scripting.FileSystemObject');
$f = $fsobj->GetFile(realpath($file));
$file = $f->Size;
} else {
$file = trim(exec("for %F in (\"" . $file . "\") do @echo %~zF"));
}
} elseif (PHP_OS == 'Darwin') {
$file = trim(shell_exec("stat -f %z " . escapeshellarg($file)));
} elseif ((PHP_OS == 'Linux') || (PHP_OS == 'FreeBSD') || (PHP_OS == 'Unix') || (PHP_OS == 'SunOS')) {
$file = trim(shell_exec("stat -c%s " . escapeshellarg($file)));
} else {
$file = filesize($file);
}
return($file)
}
The second one was that some parameters were being initialized like integers, and at some point, they failed... I worked around that by using floats instead.
The third one, was the php ftell() function (it is being called in the loop), which also returns an integer... so I have the same problem than with the filesize() function. As the value that ftell() would return when you enter to the loop would be the same value than the parameter $start has, I decided to play with a new parameter (let's call it $mm), which would enter to the loop with the same value than the parameter $start has, and then I would just add the value of the $buffer in every loop, so I wouldn't need to use the ftell() function.
It looks like this (clarify that $start is a float):
$mm = $start;
while(!feof($fp) && $p <= $end) {
if ($p + $buffer > $end) {
$buffer = $end - $p + 1;
}
set_time_limit(0);
echo fread($fp, $buffer);
$mm = $mm + $buffer;
$p = $mm;
flush();
}
$$mm and ftell() have the same value during all the loop, but for some reason, with this change it doesn't work even with <2GB files. As I thougth that maybe at some point they could have a different value, I placed a breakpoint inside the next condition:
if ($mm != $p){
$dummy = 1;
}
in:
$mm = $start;
while(!feof($fp) && ($p = ftell($fp)) <= $end) {
if ($mm != $p){
$dummy = 1;
}
if ($p + $buffer > $end) {
$buffer = $end - $p + 1;
}
set_time_limit(0);
echo fread($fp, $buffer);
$mm = $mm + $buffer;
flush();
}
and it never stopped... So I'm a bit lost, do you know what can be wrong in the worked around loop? do you know any other work around that could work to avoid the ftell() function?