[php-src] PR #24230: Fix GH-24229: fcgi_close() passes shutdown() a literal 1

Pull Request: https://github.com/php/php-src/pull/24230 Author: mpyw Fixes GH-24229. The quoted description below, and the checks it describes, were done with an LLM (Claude). I reviewed them. > fcgi_close() half-closed the connection with �߭`'�|H�9�� > shutdown(req->fd, 1), meaning SHUT_WR, as the > comment after it says. Every platform PHP supports uses 1 for > SHUT_WR, but POSIX does not fix the value. WASI uses 2, and 1 is > SHUT_RD there. > > With the read side shut, the drain loop ended at once. close() > could then run with the web server's last FCGI_STDIN unread, > and Linux reset the connection. That discarded the response before the web server read it. > > This uses SHUT_WR, which > <sys/socket.h> already provides there. The > _WIN32 branch is left as is: 1 is > SD_SEND, which is right on Windows. > > There is no test: on the supported platforms, SHUT_WR is 1, so > nothing changes. I checked that in a build of this branch, configured with > --disable-all --enable-cli --enable-cgi --enable-fpm on Debian > trixie. sapi/cgi/tests and ���5 > L�x��\�(�usapi/fpm/tests give the same results with and without this change: 132 > passed, 26 skipped, and the same 2 failures, which come from running them as root in a container. > > The fix itself was checked with php-cgi built for > wasm32-wasip1, in FastCGI mode on wazero. On Linux, 10 of 600 > requests failed before it, and none after. > > This targets PHP-8.4 as the lowest branch with bug fixes. I am happy to retarget it to master > if you see this as a portability change rather than a bug fix.