[WIP]: envconfig: Add support for secure operation system

There are many secure operation systems likes optee from linaro,
trusty from Google, and many SoC vendor has its own proprietary
one.

They don't really share many APIs, we could build trusted
application with meson as long as you prepare a proper
staging sysroot and correct cross properties.

docs/markdown/Reference-tables.md

@@ -160,6 +160,7 @@ These are provided by the `.system()` method call.
 | linux               | |
 | netbsd              | |
 | openbsd             | |
+| teeos               | Any secure Operating System, likes optee, trusty |
 | windows             | Any version of Windows |
 | sunos               | illumos and Solaris |
 

mesonbuild/envconfig.py

@@ -346,6 +346,12 @@ def is_openbsd(self) -> bool:
         """
         return self.system == 'openbsd'
 
+    def is_teeos(self) -> bool:
+        """
+        Machine is a secure Operating System (optee/trusty)
+        """
+        return self.system == 'teeos'
+
     def is_dragonflybsd(self) -> bool:
         """Machine is DragonflyBSD?"""
         return self.system == 'dragonfly'

mesonbuild/linkers/linkers.py

@@ -651,7 +651,8 @@ def import_library_args(self, implibname: str) -> T.List[str]:
         return self._apply_prefix('--out-implib=' + implibname)
 
     def thread_flags(self, env: 'Environment') -> T.List[str]:
-        if env.machines[self.for_machine].is_haiku():
+        m = env.machines[self.for_machine]
+        if m.is_haiku() or m.is_teeos():
             return []
         return ['-pthread']
 

mesonbuild/utils/universal.py

@@ -134,6 +134,7 @@ class _VerPickleLoadable(Protocol):
     'is_osx',
     'is_qnx',
     'is_sunos',
+    'is_teeos',
     'is_windows',
     'is_wsl',
     'iter_regexin_iter',
@@ -650,6 +651,10 @@ def is_openbsd() -> bool:
     return platform.system().lower() == 'openbsd'
 
 
+def is_teeos() -> bool:
+    return platform.system().lower() == 'teeos'
+
+
 def is_windows() -> bool:
     platname = platform.system().lower()
     return platname == 'windows'

test cases/common/132 get define/meson.build

@@ -19,6 +19,8 @@ system_define_map = {
   # being run on various versions of FreeBSD, just test that the define is
   # set.
   'freebsd'   : ['__FreeBSD__'],
+  # TEE likes OpenTEE didn't define any thing
+  'teeos'     : [],
 }
 
 foreach lang : ['c', 'cpp']