gzencode returns empty file

Trying to implement a "poor man's mod_gzip"

[Winnetou]

My ISP does not allow mod_gzip, so I try to create my own.

I've set up the following rule for .htaccess to route every .html file through the php file:

AddHandler doGZip .html
Action doGZip /gzip.php

This is the essence of the gzip.php file:

$file = $_SERVER["REQUEST_URI"];
$file_contents = file_get_contents($file);

$output = gzencode($file_contents, 9);
header('Vary: Accept-Encoding');
header("Content-Encoding: gzip");
header('Content-Length: ' . strlen($output));

echo $output;

I've stripped out tests for not supporting gzip etc.

However, when I open a page the browser shows an empty page and the HTTP header reads "Content-Length: 0".

When I comment the middle header line (the encoding) the browser shows an encoded file. When I write this file to disk the header of the file is a valid gzip-encoded signature (1F 8B 08).

When I try to immediately gzdecode the output it's empty too:

if( $f = @fopen( "encoded.txt", 'w' ) ) {
fputs( $f, $output );
fclose( $f );
}
if( $f = @fopen( "decoded.txt", 'w' ) ) {
$output = gzdecode($output);
fputs( $f, $output );
fclose( $f );
}

What am I missing? Thanks!

[Winnetou]

Update: The gzdecode() function does not exist in PHP, see [au2.php.net...] which also has a link to a function someone has written.

When I apply the encoded content to this function it successfully decodes the webpage.

But my browser doesn't.

Any clues warmly welcomed. Thank you.

[jdMorgan]

Where's your Content-Type header generated?

Jim

[Winnetou]

Hi Jim,

I'm using the .htaccess rule to redirect to the php file which does the rest.

As I understand it the gzencode command creates the entire file including the header. I have checked the spec (http://www.gzip.org/zlib/rfc-gzip.html) and compared the first few header bytes which are correct.

The file the browser decodes shows in Firebug "Content-Type text/html", so I assume that's encoded correctly. However, it does also show "Content-Length 0". Closer inspection of the spec reveals that the uncompressed file length should go into the last byte (CRC32 and ISIZE), but that byte is #00 in my tests.

[Winnetou]

Looks like it's an Apache configuration problem.

I just copied the exact same .htaccess and gzip.php to another server installation (at work) and there it works fine.

I'll be comparing configuration files and post the results back.

[Winnetou]

Sorry for the long pause, but I was sick.

I managed to make it work with Apache 2.0 by deleting any further PHP directives after the "echo $output" line. I couldn't figure out why my Apache 2.2 installation at work was more forgiving.