PHP binary path hardcoded

[BilboTav]

Would it be possible to be able to override path to PHP binary inside this handler, please? Maybe using some ENV variable?
I am using wrapper for PHP 8.5 under WSL1, so PHP_BINARY constant does not return wrapper, but original binary. Therefore I get this error when running composer under PHP 8.5 with Xdebug enabled:

PHP Warning:  proc_open(): posix_spawn() failed: Exec format error in phar:///usr/local/bin/composer/vendor/composer/xdebug-handler/src/XdebugHandler.php on line 300
PHP Stack trace:
PHP   1. {main}() /usr/local/bin/composer:0
PHP   2. require() /usr/local/bin/composer:29
PHP   3. Composer\XdebugHandler\XdebugHandler->check() phar:///usr/local/bin/composer/bin/composer:43
PHP   4. Composer\XdebugHandler\XdebugHandler->restart($command = [0 => '/usr/bin/php8.5-bin', 1 => '-n', 2 => '-c', 3 => '/tmp/fh3d7t9hgapgdGR3Iik', 4 => '/usr/local/bin/composer']) phar:///usr/local/bin/composer/vendor/composer/xdebug-handler/src/XdebugHandler.php:149
PHP   5. Composer\XdebugHandler\XdebugHandler->doRestart($command = [0 => '/usr/bin/php8.5-bin', 1 => '-n', 2 => '-c', 3 => '/tmp/fh3d7t9hgapgdGR3Iik', 4 => '/usr/local/bin/composer']) phar:///usr/local/bin/composer/vendor/composer/xdebug-handler/src/XdebugHandler.php:274
PHP   6. proc_open($command = [0 => '/usr/bin/php8.5-bin', 1 => '-n', 2 => '-c', 3 => '/tmp/fh3d7t9hgapgdGR3Iik', 4 => '/usr/local/bin/composer'], $descriptor_spec = [], $pipes = NULL) phar:///usr/local/bin/composer/vendor/composer/xdebug-handler/src/XdebugHandler.php:300

It would be nice if path to PHP binary could be specified manually here.

Here is relevant part:
https://github.com/composer/xdebug-handler/blob/main/src/XdebugHandler.php#L438

Instead of:

$php = [PHP_BINARY];

Maybe something like:

$php = [getenv('PHP_BINARY') ?: PHP_BINARY];

Or some other solution...?

Thanks!

[johnstevenson]

Please provide the code that shows exactly what you are doing so we can reproduce it.

[BilboTav]

Hi, thank You for responding so quickly!

There is no code, its more like situation explained, so first a bit background:
My issue is a bit peculiar - its for WSL (Windows Linux Subsystem) version 1 only - which I use. On WSL1 some newer binaries can not be run directly, like PHP 8.5, it throws this error:

cannot execute binary file: Exec format error

Solution is to run it like this:

/lib64/ld-linux-x86-64.so.2 <binary>

So specifically for PHP 8.5 I have this wrapper script as /usr/bin/php8.5:

#!/usr/bin/env bash

SCRIPT_PATH=$(realpath $0)
SCRIPT_DIR=$(dirname $SCRIPT_PATH)

export PHP_BINARY=$SCRIPT_DIR/php8.5

exec /lib64/ld-linux-x86-64.so.2 $SCRIPT_DIR/php8.5-bin "$@"

Than it works fine, with some caveats - one of them is what constant PHP_BINARY returns. Which is sometimes used to invoke another php script from code inside.

In this case PHP_BINARY does not return /usr/bin/php8.5 - wrapper script, but /usr/bin/php8.5-bin - original binary, which of course throws error to me when invoked.

Which leads to problems like in Your library.

I encountered similar situation in Pie PHP package system somewhere in code, they were invoking PHP binary - and what they did is they had the option to specify path to PHP binary manually, namely using ENV variables passed inside.

So what I am suggesting is doing something similar here - being able to specify path to PHP binary manually or use PHP_BINARY constant as default.

So in Your code instead of using PHP_BINARY directly, maybe some method like this:

private function getPhpBinary(): string
{
   // Get PHP binary based on ENV variable if set or default use system constant
   return getenv('PHP_BINARY') ?: PHP_BINARY;
}

Then it can be used:

https://github.com/composer/xdebug-handler/blob/main/src/XdebugHandler.php#L438

$php = [$this->getPhpBinary()];

https://github.com/composer/xdebug-handler/blob/main/src/XdebugHandler.php#L593

if (!file_exists($this->getPhpBinary())) {
   $info = 'PHP_BINARY is not available';
   return false;
}

Thank You!

[johnstevenson]

I think your easiest solution is to use the XDEBUG_MODE environment variable to control its behaviour. Setting this to off will prevent the restart.