error_log() doesn't respect error_log_mode INI setting

[SPKSmithy]

Description

Logs created by PHP's error_log INI setting have the correct mode but the error_log() function appears to ignore the error_log_mode setting. I've tried setting error_log_mode using ini_set() and as a PHP-FPM php_admin_value.

The following code:

<?php
ini_set('error_log_mode', '0o200');
error_log('Something went wrong', 3, 'exceptions.log');

Resulted in this output:

-rw-r--r--. 1 apache apache 20 Nov 24 23:07 exceptions.log

But I expected this output instead:

--w-------. 1 apache apache 20 Nov 24 23:07 exceptions.log

PHP Version

PHP 8.2.13

Operating System

Rocky Linux 9.2 (Blue Onyx)

[nielsdos]

Looks like error_log_mode is only used for the file set by error_log INI setting, and is thus only used when using error_log with a message_type other than 3.

According to https://www.php.net/manual/en/errorfunc.configuration.php#ini.error-log-mode

File mode for the file described set in error_log.
The link points to the error_log INI setting.

Although I agree this is confusing, I think this behaves as expected.

But just to be sure: cc @mikhainin @bukka

[SPKSmithy]

If error_log_mode is only intended to work with the error_log INI setting then should the error_log() function have an equivalent? Maybe an option passed to the additional_headers parameter since that's not currently used for type 3 messages.

[mikhainin]

I tend to agree with @SPKSmithy that using this setting for error_log() is a reasonable improvement.
We just didn't think about it when initial patch was implemented.

[bukka]

Yeah agree that it would be reasonable addition - changed to feature request...

[benliew68]

Been working on this in master...benliew68:error-log-use-ini-file-mode. Type 3 messages can have "use_ini_mode" passed as the header to use the error_log_mode INI directive, otherwise they will use the default file mode 0666 when creating the log file.

Thoughts/feedback on this implementation would be greatly appreciated.

[nielsdos]

Hi @benliew68
Thanks for the effort! Always feel free to open a pull request even if it's in-draft; because that's a bit easier to give feedback on.
As for the approach, I think it's not a very good idea to add a flag to put error log handling inside the stream functions. I think a better approach is to extend the API such that the permissions may be provided as an argument, or that they can be changed afterwards.