From 7b3a2053406906585ac7ec4aec38f31b5102826c Mon Sep 17 00:00:00 2001
From: Sergey Fedorov <barracuda@macos-powerpc.org>
Date: Tue, 17 Sep 2024 14:07:48 +0800
Subject: [PATCH 1/2] Thread: fix dispatch usage on macOS

---
 src/Thread.c | 12 ++++++------
 src/Thread.h |  9 ++++++++-
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git src/Thread.c src/Thread.c
index f4d43fb..e2964b2 100644
--- src/Thread.c
+++ src/Thread.c
@@ -234,7 +234,7 @@ sem_type Thread_create_sem(int *rc)
 		        NULL                /* object name */
 		        );
 		*rc = (sem == NULL) ? GetLastError() : 0;
-	#elif defined(OSX)
+	#elif defined(OSX) && defined(HAS_DISPATCH)
 		sem = dispatch_semaphore_create(0L);
 		*rc = (sem == NULL) ? -1 : 0;
 	#else
@@ -259,7 +259,7 @@ int Thread_wait_sem(sem_type sem, int timeout)
  * so I've used trywait in a loop instead. Ian Craggs 23/7/2010
  */
 	int rc = -1;
-#if !defined(_WIN32) && !defined(_WIN64) && !defined(OSX)
+#if !defined(_WIN32) && !defined(_WIN64) && !(defined(OSX) && defined(HAS_DISPATCH))
 #define USE_TRYWAIT
 #if defined(USE_TRYWAIT)
 	int i = 0;
@@ -276,7 +276,7 @@ int Thread_wait_sem(sem_type sem, int timeout)
 		rc = WaitForSingleObject(sem, timeout < 0 ? 0 : timeout);
 		if (rc == WAIT_TIMEOUT)
 			rc = ETIMEDOUT;
-	#elif defined(OSX)
+	#elif defined(OSX) && defined(HAS_DISPATCH)
 		/* returns 0 on success, non-zero if timeout occurred */
 		rc = (int)dispatch_semaphore_wait(sem, dispatch_time(DISPATCH_TIME_NOW, (int64_t)timeout*1000000L));
 		if (rc != 0)
@@ -320,7 +320,7 @@ int Thread_check_sem(sem_type sem)
 #if defined(_WIN32) || defined(_WIN64)
 	/* if the return value is not 0, the semaphore will not have been decremented */
 	return WaitForSingleObject(sem, 0) == WAIT_OBJECT_0;
-#elif defined(OSX)
+#elif defined(OSX) && defined(HAS_DISPATCH)
 	/* if the return value is not 0, the semaphore will not have been decremented */
 	return dispatch_semaphore_wait(sem, DISPATCH_TIME_NOW) == 0;
 #else
@@ -344,7 +344,7 @@ int Thread_post_sem(sem_type sem)
 	#if defined(_WIN32) || defined(_WIN64)
 		if (SetEvent(sem) == 0)
 			rc = GetLastError();
-	#elif defined(OSX)
+	#elif defined(OSX) && defined(HAS_DISPATCH)
 		rc = (int)dispatch_semaphore_signal(sem);
 	#else
 		int val;
@@ -371,7 +371,7 @@ int Thread_destroy_sem(sem_type sem)
 	FUNC_ENTRY;
 	#if defined(_WIN32) || defined(_WIN64)
 		rc = CloseHandle(sem);
-	#elif defined(OSX)
+	#elif defined(OSX) && defined(HAS_DISPATCH)
 	  dispatch_release(sem);
 	#else
 		rc = sem_destroy(sem);
diff --git src/Thread.h src/Thread.h
index b0c823b..721b027 100644
--- src/Thread.h
+++ src/Thread.h
@@ -29,6 +29,13 @@
 #endif
 #endif
 
+#ifdef __APPLE__
+	#include <AvailabilityMacros.h>
+	#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060 && !defined(__ppc__)
+	  #define HAS_DISPATCH
+	#endif
+#endif
+
 #include "MQTTExportDeclarations.h"
 
 #include "MQTTClient.h"
@@ -54,7 +61,7 @@
 	typedef thread_return_type (*thread_fn)(void*);
 	typedef struct { pthread_cond_t cond; pthread_mutex_t mutex; } cond_type_struct;
 	typedef cond_type_struct *cond_type;
-	#if defined(OSX)
+	#if defined(OSX) && defined(HAS_DISPATCH)
 	  #include <dispatch/dispatch.h>
 	  typedef dispatch_semaphore_t sem_type;
 	#else