protect unistd.h inclusion with a check for Unix

This ensures that all the inclusions of unistd.h inclusion are protected
with the check that the header exists.  This header is only available on
unix like environments to define the standard of compliance.  This
protection is needed for other environments like Windows.

Signed-off-by: Daniel A. Steffen <dsteffen@apple.com>

Author: compnerd

CMakeLists.txt

@@ -221,7 +221,6 @@ check_include_files("strings.h" HAVE_STRINGS_H)
 check_include_files("sys/guarded.h" HAVE_SYS_GUARDED_H)
 check_include_files("sys/stat.h" HAVE_SYS_STAT_H)
 check_include_files("sys/types.h" HAVE_SYS_TYPES_H)
-check_include_files("unistd.h" HAVE_UNISTD_H)
 check_include_files("objc/objc-internal.h" HAVE_OBJC)
 
 if(HAVE_MACH)

cmake/config.h.in

@@ -192,9 +192,6 @@
 /* Define to 1 if you have the <TargetConditionals.h> header file. */
 #cmakedefine HAVE_TARGETCONDITIONALS_H
 
-/* Define to 1 if you have the <unistd.h> header file. */
-#cmakedefine01 HAVE_UNISTD_H
-
 /* Define to 1 if you have the `_pthread_workqueue_init' function. */
 #cmakedefine HAVE__PTHREAD_WORKQUEUE_INIT
 

dispatch/dispatch.h

@@ -35,7 +35,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <stdarg.h>
-#if !defined(HAVE_UNISTD_H) || HAVE_UNISTD_H
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
 #include <unistd.h>
 #endif
 #include <fcntl.h>

private/private.h

@@ -41,7 +41,7 @@
 #include <mach/mach.h>
 #include <mach/message.h>
 #endif
-#if HAVE_UNISTD_H
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
 #include <unistd.h>
 #endif
 #include <pthread.h>

src/internal.h

@@ -285,7 +285,7 @@ DISPATCH_EXPORT DISPATCH_NOTHROW void dispatch_atfork_child(void);
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#if HAVE_UNISTD_H
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
 #include <unistd.h>
 #endif
 

src/queue.c

@@ -903,7 +903,9 @@ libdispatch_init(void)
 }
 
 #if DISPATCH_USE_THREAD_LOCAL_STORAGE
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
 #include <unistd.h>
+#endif
 #include <sys/syscall.h>
 
 #ifndef __ANDROID__