[gtk-vnc] build: implement some macOS specific fixes

[Daniel P. Berrange <dberrange src gnome org>]

commit 94377d8716d3b4c7e78d763ac074fa937415fb44
Author: Tom Schoonjans <Tom Schoonjans diamond ac uk>
Date:   Wed Aug 7 20:56:47 2019 +0100

    build: implement some macOS specific fixes
    
    * Add some CPPFLAGS
    * Ensure -Wl,--no-undefined is only used when supported, which is not
    the case on macOS
    * Add darwin_versions for correct versioning

 meson.build        | 2 +-
 src/continuation.h | 4 ++++
 src/meson.build    | 9 ++++++---
 3 files changed, 11 insertions(+), 4 deletions(-)
---
diff --git a/meson.build b/meson.build
index 1115056..737c47a 100644
--- a/meson.build
+++ b/meson.build
@@ -7,7 +7,7 @@ project(
     'c_std=gnu99',
     'warning_level=1',
   ],
-  meson_version: '>= 0.46.0'
+  meson_version: '>= 0.48.0'
 )
 
 version_info = meson.project_version().split('.')
diff --git a/src/continuation.h b/src/continuation.h
index a416837..e00bffb 100644
--- a/src/continuation.h
+++ b/src/continuation.h
@@ -21,6 +21,10 @@
 #ifndef _CONTINUATION_H_
 #define _CONTINUATION_H_
 
+#ifdef __APPLE__
+  #define _XOPEN_SOURCE 600
+#endif
+
 #include <ucontext.h>
 #include <stddef.h>
 
diff --git a/src/meson.build b/src/meson.build
index 956f189..64f7439 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -89,7 +89,7 @@ else
 endif
 
 gvnc_link_args = []
-if host_machine.system() != 'windows'
+if meson.get_compiler('c').has_link_argument('-Wl,--no-undefined')
   gvnc_link_args += ['-Wl,--no-undefined']
 endif
 
@@ -123,6 +123,7 @@ gvnc = library(
   include_directories: gvnc_inc,
   link_args: gvnc_link_args,
   version: '0.0.1',
+  darwin_versions: ['1.0', '1.1'],
   soversion: '0',
   install: true,
 )
@@ -178,7 +179,7 @@ if libpulse_dep.found()
   ]
 
   gvncpulse_link_args = []
-  if host_machine.system() != 'windows'
+  if meson.get_compiler('c').has_link_argument('-Wl,--no-undefined')
     gvncpulse_link_args += ['-Wl,--no-undefined']
   endif
 
@@ -206,6 +207,7 @@ if libpulse_dep.found()
     include_directories: gvncpulse_inc,
     link_args: gvncpulse_link_args,
     version: '0.0.1',
+    darwin_versions: ['1.0', '1.1'],
     soversion: '0',
     install: true,
   )
@@ -337,7 +339,7 @@ endforeach
 
 
 gtk_vnc_link_args = []
-if host_machine.system() != 'windows'
+if meson.get_compiler('c').has_link_argument('-Wl,--no-undefined')
   gtk_vnc_link_args += ['-Wl,--no-undefined']
 endif
 
@@ -369,6 +371,7 @@ gtk_vnc = library(
   include_directories: gtk_vnc_inc,
   link_args: gtk_vnc_link_args,
   version: '0.0.2',
+  darwin_versions: ['1.0', '1.2'],
   soversion: '0',
   install: true,
 )