pcntl: Adding pcntl_rfork support.

UPGRADING

@@ -346,6 +346,9 @@ PHP 8.1 UPGRADE NOTES
   . Added array_is_list(array $array), which will return true if the array keys are 0 .. count($array)-1 in that order.
     RFC: https://wiki.php.net/rfc/is_list
 
+- pcntl:
+  . Added pcntl_rfork for FreeBSD variants
+
 - Reflection:
   . Added ReflectionFunctionAbstract::getClosureUsedVariables
 

ext/pcntl/config.m4

@@ -7,7 +7,7 @@ if test "$PHP_PCNTL" != "no"; then
   AC_CHECK_FUNCS([fork], [], [AC_MSG_ERROR([pcntl: fork() not supported by this platform])])
   AC_CHECK_FUNCS([waitpid], [], [AC_MSG_ERROR([pcntl: waitpid() not supported by this platform])])
   AC_CHECK_FUNCS([sigaction], [], [AC_MSG_ERROR([pcntl: sigaction() not supported by this platform])])
-  AC_CHECK_FUNCS([getpriority setpriority wait3 wait4 sigwaitinfo sigtimedwait unshare])
+  AC_CHECK_FUNCS([getpriority setpriority wait3 wait4 sigwaitinfo sigtimedwait unshare rfork])
 
   AC_MSG_CHECKING([for siginfo_t])
   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[

ext/pcntl/pcntl.c

@@ -340,6 +340,36 @@ void php_register_signal_constants(INIT_FUNC_ARGS)
 	REGISTER_LONG_CONSTANT("CLONE_NEWCGROUP",	CLONE_NEWCGROUP, CONST_CS | CONST_PERSISTENT);
 #endif
 #endif
+
+#ifdef HAVE_RFORK
+#ifdef RFPROC
+	REGISTER_LONG_CONSTANT("RFPROC",	RFPROC, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFNOWAIT
+	REGISTER_LONG_CONSTANT("RFNOWAIT",	RFNOWAIT, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFCFDG
+	REGISTER_LONG_CONSTANT("RFCFDG",	RFCFDG, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFFDG
+	REGISTER_LONG_CONSTANT("RFFDG",	RFFDG, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFLINUXTHPN
+	REGISTER_LONG_CONSTANT("RFLINUXTHPN",	RFLINUXTHPN, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFMEM
+	REGISTER_LONG_CONSTANT("RFMEM",	RFMEM, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFSIGSHARE
+	REGISTER_LONG_CONSTANT("RFSIGSHARE",	RFSIGSHARE, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFSIGZMB
+	REGISTER_LONG_CONSTANT("RFSIGSZMB",	RFSIGSZMB, CONST_CS | CONST_PERSISTENT);
+#endif
+#ifdef RFTHREAD
+	REGISTER_LONG_CONSTANT("RFTHREAD",	RFTHREAD, CONST_CS | CONST_PERSISTENT);
+#endif
+#endif
 }
 
 static void php_pcntl_register_errno_constants(INIT_FUNC_ARGS)
@@ -1468,6 +1498,54 @@ PHP_FUNCTION(pcntl_unshare)
 /* }}} */
 #endif
 
+#ifdef HAVE_RFORK
+/* {{{ proto bool pcntl_rfork([int flags|custom signal)
+   More control over the process creation is given over fork/vfork. */
+PHP_FUNCTION(pcntl_rfork)
+{
+  zend_long flags;
+  zend_long csignal;
+  pid_t pid;
+
+  ZEND_PARSE_PARAMETERS_START(1, 2)
+    Z_PARAM_LONG(flags)
+    Z_PARAM_OPTIONAL
+    Z_PARAM_LONG(csignal)
+  ZEND_PARSE_PARAMETERS_END();
+
+  /* This is a flag to use with great caution in general, preferably not within PHP */
+  if ((flags & RFMEM) != 0) {
+    flags &= ~RFMEM;
+  }
+
+  /* A new pid is required */
+  flags |= RFPROC;
+
+  if (ZEND_NUM_ARGS() == 2 && (flags & RFTSIGZMB) != 0) {
+    flags |= RFTSIGFLAGS(csignal);
+  }
+
+  pid = rfork(flags);
+
+  if (pid == -1) {
+    PCNTL_G(last_error) = errno;
+    switch (errno) {
+      case EINVAL:
+        php_error_docref(NULL, E_WARNING, "RFFDG and RFCFDG modes are mutually exclusive");
+        break;
+      case EAGAIN:
+        php_error_docref(NULL, E_WARNING, "Maximum process creations limit reached\n");
+        break;
+      default:
+        php_error_docref(NULL, E_WARNING, "Error %d", errno);
+    }
+  }
+
+  RETURN_LONG((zend_long) pid);
+}
+#endif
+/* }}} */
+
 static void pcntl_interrupt_function(zend_execute_data *execute_data)
 {
 	pcntl_signal_dispatch();

ext/pcntl/pcntl.stub.php

@@ -79,3 +79,7 @@ function pcntl_async_signals(?bool $enable = null): bool {}
 #ifdef HAVE_UNSHARE
 function pcntl_unshare(int $flags): bool {}
 #endif
+
+#ifdef HAVE_RFORK
+function pcntl_rfork(int $flags, int $signal): int{}
+#endif

ext/pcntl/pcntl_arginfo.h

@@ -119,6 +119,13 @@ ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_pcntl_unshare, 0, 1, _IS_BOOL, 0
 ZEND_END_ARG_INFO()
 #endif
 
+#if defined(HAVE_RFORK)
+ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_pcntl_rfork, 0, 1, IS_LONG, 0)
+	ZEND_ARG_TYPE_INFO(0, flags, IS_LONG, 0)
+	ZEND_ARG_TYPE_INFO(0, signal, IS_LONG, 0)
+ZEND_END_ARG_INFO()
+#endif
+
 
 ZEND_FUNCTION(pcntl_fork);
 ZEND_FUNCTION(pcntl_waitpid);
@@ -158,6 +165,9 @@ ZEND_FUNCTION(pcntl_async_signals);
 #if defined(HAVE_UNSHARE)
 ZEND_FUNCTION(pcntl_unshare);
 #endif
+#if defined(HAVE_RFORK)
+ZEND_FUNCTION(pcntl_rfork);
+#endif
 
 
 static const zend_function_entry ext_functions[] = {

ext/pcntl/tests/pcntl_rfork.phpt

@@ -0,0 +1,24 @@
+--TEST--
+Test function pcntl_rfork() with no flag.
+--SKIPIF--
+<?php
+	if (!extension_loaded('pcntl')) die('skip pcntl extension not available');
+	elseif (!extension_loaded('posix')) die('skip posix extension not available');
+  if (!function_exists('pcntl_rfork')) die('skip pcntl_rfork unavailable');
+?>
+--FILE--
+<?php
+echo "*** Test with no flags ***\n";
+
+$pid = pcntl_rfork(0);
+if ($pid > 0) {
+	pcntl_wait($status);
+	var_dump($pid);
+} else {
+	var_dump($pid);
+}
+?>
+--EXPECTF--
+*** Test with no flags ***
+int(0)
+int(%d)

ext/pcntl/tests/pcntl_rfork_nowait.phpt

@@ -0,0 +1,24 @@
+--TEST--
+Test function pcntl_rfork() with no wait flag.
+--SKIPIF--
+<?php
+	if (!extension_loaded('pcntl')) die('skip pcntl extension not available');
+	elseif (!extension_loaded('posix')) die('skip posix extension not available');
+  if (!function_exists('pcntl_rfork')) die('skip pcntl_rfork unavailable');
+?>
+--FILE--
+<?php
+echo "*** Test by with child not reporting to the parent ***\n";
+
+$pid = pcntl_rfork(RFNOWAIT|RFTSIGZMB,SIGUSR1);
+if ($pid > 0) {
+	var_dump($pid);
+} else {
+	var_dump($pid);
+  sleep(1);
+}
+?>
+--EXPECTF--
+*** Test by with child not reporting to the parent ***
+int(%d)
+int(0)