php-in-php: VmGzStreamNative — pure PHP gz* stream I/O without libz FFI (#1492, ext/zlib/zlib.c)

[PurHur]

Category

php-in-php | stdlib

Problem

ext/standard/VmGzStreamNative.php opens compress.zlib:// streams via libz FFI (gzopen, gzread, gzwrite, gzclose). Bootstrap and self-host paths already have pure-PHP zlib encode/decode (VmZlibNative, ext/zstd-style migration #8837); gz stream wrappers should follow the same PHP-in-PHP strategy.

php-src reference

• php/php-src ext/zlib/zlib.c — php_gzopen, stream ops
• php/php-src ext/zlib/zlib_fopen_wrapper.c — compress.zlib:// wrapper

Repro

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
grep -c "FFI" ext/standard/VmGzStreamNative.php
php bin/vm.php test/repro-maintainer/gzcompress_native_only.php 2>/dev/null || true'

Add test/repro-maintainer/gz_stream_php_in_php_probe.php:

<?php
$path = sys_get_temp_dir() . '/phpc_gz_probe_' . getmypid() . '.gz';
$zp = gzopen($path, 'wb9');
gzwrite($zp, 'hello');
gzclose($zp);
$zr = gzopen($path, 'rb');
echo gzread($zr, 100), "\n";
gzclose($zr);
unlink($path);

Runtime	Expected
Zend	hello
VM today	works via libz FFI

Done target: same output with no libz FFI in VmGzStreamNative.

Scope

Layer	Path
PHP	New ext/standard/VmGzStreamPure.php or extend VmZlibNative with stream handle table
VM	ext/standard/gzopen.php, gzread.php, VmFs.php gz placeholder adoption
JIT	lib/JIT/Builtin/GzStreamIoJit.php — share core with VM
Tests	test/unit/VmZlibNativeTest.php, compliance gz stream PHPT

Done when (php-src-strict)

• VmGzStreamNative FFI removed; gz stream repro passes on VM
• Runtime-shrink unit test documents C/FFI symbols deleted
• make north-star5-verify-fast green after self-host spine touches gz paths

Related

#6168 · #8837 · #8868 · #1492

[PurHur]

claim: PHP Runtime → PHP — batch (#8936, #8837) — VmGzStreamPure buffered I/O, drop libz FFI from VmGzStreamNative.

[PurHur]

Merged via PR #12049.

Verification (Docker):

• vendor/bin/phpunit --filter VmGzStreamRuntimeShrinkTest — OK (5 tests, 26 assertions)
• php bin/vm.php test/repro-maintainer/gz_stream_php_in_php_probe.php — hello
• make bootstrap-selfhost-vm-driver-execute-probe — OK

LOC: VmGzStreamNative.php ~202 → ~44 (−158 FFI). New SSOT: ext/standard/VmGzStreamPure.php.