Adding Dummy sandbox and nolocal platform

buildstream/_platform/darwin.py

@@ -19,7 +19,7 @@ import os
 import resource
 
 from .._exceptions import PlatformError
-from ..sandbox import SandboxChroot
+from ..sandbox import SandboxChroot, DummySandbox
 
 from . import Platform
 
@@ -38,7 +38,7 @@ class Darwin(Platform):
         return self._artifact_cache
 
     def create_sandbox(self, *args, **kwargs):
-        return SandboxChroot(*args, **kwargs)
+        return DummySandbox(*args, **kwargs)
 
     def get_cpu_count(self, cap=None):
         if cap < os.cpu_count():

buildstream/_platform/linux.py

@@ -24,7 +24,7 @@ from .. import _site
 from .. import utils
 from .._artifactcache.cascache import CASCache
 from .._message import Message, MessageType
-from ..sandbox import SandboxBwrap
+from ..sandbox import SandboxBwrap, DummySandbox
 
 from . import Platform
 
@@ -48,10 +48,13 @@ class Linux(Platform):
         return self._artifact_cache
 
     def create_sandbox(self, *args, **kwargs):
-        # Inform the bubblewrap sandbox as to whether it can use user namespaces or not
-        kwargs['user_ns_available'] = self._user_ns_available
-        kwargs['die_with_parent_available'] = self._die_with_parent_available
-        return SandboxBwrap(*args, **kwargs)
+        if not self._local_sandbox_available():
+            return DummySandbox(*args, **kwargs)
+        else:
+            # Inform the bubblewrap sandbox as to whether it can use user namespaces or not
+            kwargs['user_ns_available'] = self._user_ns_available
+            kwargs['die_with_parent_available'] = self._die_with_parent_available
+            return SandboxBwrap(*args, **kwargs)
 
     ################################################
     #              Private Methods                 #

buildstream/_platform/platform.py

@@ -54,6 +54,8 @@ class Platform():
             backend = 'linux'
         elif sys.platform.startswith('darwin'):
             backend = 'darwin'
+        elif not (os.path.exists(utils.get_host_tool('bwrap')) and os.path.exists('/dev/fuse')):
+            backend = 'no_local'
         else:
             backend = 'unix'
 

buildstream/sandbox/__init__.py

@@ -21,3 +21,4 @@ from .sandbox import Sandbox, SandboxFlags
 from ._sandboxchroot import SandboxChroot
 from ._sandboxbwrap import SandboxBwrap
 from ._sandboxremote import SandboxRemote
+from ._dummysandbox import DummySandbox

buildstream/sandbox/_dummysandbox.py

+#
+#  Copyright (C) 2017 Codethink Limited
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+#  Authors:
+
+from .._exceptions import SandboxError
+from . import Sandbox
+
+
+class DummySandbox(Sandbox):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        uid = self._get_config().build_uid
+        gid = self._get_config().build_gid
+        if uid != 0 or gid != 0:
+            raise SandboxError("Chroot sandboxes cannot specify a non-root uid/gid "
+                               "({},{} were supplied via config)".format(uid, gid))
+
+        self.mount_map = None
+
+    def run(self, command, flags, *, cwd=None, env=None):
+
+        # Default settings
+        if cwd is None:
+            cwd = self._get_work_directory()
+
+        if cwd is None:
+            cwd = '/'
+
+        if env is None:
+            env = self._get_environment()
+
+        # Naive getcwd implementations can break when bind-mounts to different
+        # paths on the same filesystem are present. Letting the command know
+        # what directory it is in makes it unnecessary to call the faulty
+        # getcwd.
+        env['PWD'] = cwd
+
+        if not self._has_command(command[0], env):
+            raise SandboxError("Staged artifacts do not provide command "
+                               "'{}'".format(command[0]),
+                               reason='missing-command')
+
+        raise SandboxError("This platform does not support local builds")