zend stack: prepare zend_call_stack_get implementation for OpenBSD. (php#11578)

Author: devnexen

Zend/Zend.m4

@@ -146,7 +146,7 @@ _LT_AC_TRY_DLOPEN_SELF([
 ])
 
 dnl Checks for library functions.
-AC_CHECK_FUNCS(getpid kill sigsetjmp pthread_getattr_np pthread_attr_get_np pthread_get_stackaddr_np pthread_attr_getstack gettid)
+AC_CHECK_FUNCS(getpid kill sigsetjmp pthread_getattr_np pthread_attr_get_np pthread_get_stackaddr_np pthread_attr_getstack pthread_stackseg_np gettid)
 
 dnl Test whether the stack grows downwards
 dnl Assumes contiguous stack

Zend/zend_call_stack.c

@@ -35,7 +35,7 @@
 #  include <sys/types.h>
 # endif
 #endif /* ZEND_WIN32 */
-#if defined(__linux__) || defined(__FreeBSD__) || defined(__APPLE__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__APPLE__) || defined(__OpenBSD__)
 # include <pthread.h>
 #endif
 #ifdef __FreeBSD__
@@ -44,6 +44,9 @@
 # include <sys/sysctl.h>
 # include <sys/user.h>
 #endif
+#ifdef __OpenBSD__
+# include <pthread_np.h>
+#endif
 #ifdef __linux__
 #include <sys/syscall.h>
 #endif
@@ -432,6 +435,27 @@ static bool zend_call_stack_get_macos(zend_call_stack *stack)
 }
 #endif /* defined(__APPLE__) && defined(HAVE_PTHREAD_GET_STACKADDR_NP) */
 
+#if defined(HAVE_PTHREAD_STACKSEG_NP)
+static bool zend_call_stack_get_openbsd(zend_call_stack *stack)
+{
+	stack_t ss;
+
+	if (pthread_stackseg_np(pthread_self(), &ss) != 0) {
+		return false;
+	}
+
+	stack->base = (char *)ss.ss_sp - ss.ss_size;
+	stack->max_size = ss.ss_size - sysconf(_SC_PAGE_SIZE);
+
+	return true;
+}
+#else
+static bool zend_call_stack_get_openbsd(zend_call_stack *stack)
+{
+	return false;
+}
+#endif /* defined(HAVE_PTHREAD_STACKSEG_NP) */
+
 /** Get the stack information for the calling thread */
 ZEND_API bool zend_call_stack_get(zend_call_stack *stack)
 {
@@ -451,6 +475,10 @@ ZEND_API bool zend_call_stack_get(zend_call_stack *stack)
 		return true;
 	}
 
+	if (zend_call_stack_get_openbsd(stack)) {
+		return true;
+	}
+
 	return false;
 }