Stdlib: mail() additional_headers array|string + header ValueError (ext/standard/mail.c)

[PurHur]

Category

stdlib | child of #3285 (mail transport depth)

Problem

After sendmail transport (#3285), mail() still only accepts a string for $additional_headers. Zend 8.x accepts array|string and validates via php_mail_build_headers() — rejecting embedded To/Subject, invalid field names, and CR/LF/NUL in values with ValueError / TypeError.

php-src reference

• php/php-src ext/standard/mail.c — PHP_FUNCTION(mail), php_mail_build_headers, php_mail_build_headers_check_field_*

Repro (failure after #3285 transport lands)

<?php
try {
    mail('a@b.c', 'subj', 'body', ['To' => 'evil@x']);
    echo "NO_THROW\n";
} catch (ValueError $e) {
    echo "ValueError\n";
}

Engine	Result
Zend 8.4	ValueError (additional headers cannot contain To)
VM today	TypeError (string required) or wrong accept

Scope

Path	Work
ext/standard/VmMail.php / mail.php	array headers → RFC2822 lines; ValueError parity
Tests	test/compliance/cases/stdlib/mail_headers_array.phpt

Done when (php-src-strict)

• mail(..., ['From' => 'x@y']) builds header line and reaches transport
• To / Subject keys → ValueError matching Zend message shape
• Invalid CR/LF in header values → ValueError
• Compliance .phpt green on VM

Related

• Parent Stdlib: mail() — send message via sendmail/MTA (ext/standard/mail.c parity) #3285 · follow-ups: mail.add_x_header, additional_params escape

[PurHur]

claim: PHP Compiler STD Lib Advanced — batch (issues #3285, #21432, #21433, #21434); sequential after #3285

[PurHur]

claim: PHP Compiler STD Lib Advanced — implementing #21432 now (after #3285/#21435 merged)

[PurHur]

Merged #21436

Verification

• php bin/vm.php test/repro/issue_21432_mail_headers_array.php → OK
• vendor/bin/phpunit test/compliance/VMTest.php --filter 'mail_headers_array|mail_sendmail…' → OK (5)

Next: #21433 mail.add_x_header.