Merge branch 'abderrahim/arch' into 'bst-1'

element.py: add configuration for sandbox architecture and os

See merge request BuildStream/buildstream!1934

4 files changed, 40 insertions, 10 deletions

diff --git a/buildstream/_versions.py b/buildstream/_versions.py
index 383429902..2110c2889 100644
--- a/buildstream/_versions.py
+++ b/buildstream/_versions.py
@@ -23,7 +23,7 @@
 # This version is bumped whenever enhancements are made
 # to the `project.conf` format or the core element format.
 #
-BST_FORMAT_VERSION = 17
+BST_FORMAT_VERSION = 18
 
 
 # The base BuildStream artifact version
diff --git a/buildstream/element.py b/buildstream/element.py
index af0c1a27c..f442d9c85 100644
--- a/buildstream/element.py
+++ b/buildstream/element.py
@@ -2254,6 +2254,8 @@ class Element(Plugin):
             project.ensure_fully_loaded()
             sandbox_config = _yaml.node_chain_copy(project._sandbox)
 
+        host_os, _, _, _, host_arch = os.uname()
+
         # The default config is already composited with the project overrides
         sandbox_defaults = _yaml.node_get(self.__defaults, Mapping, 'sandbox', default_value={})
         sandbox_defaults = _yaml.node_chain_copy(sandbox_defaults)
@@ -2263,10 +2265,13 @@ class Element(Plugin):
         _yaml.node_final_assertions(sandbox_config)
 
         # Sandbox config, unlike others, has fixed members so we should validate them
-        _yaml.node_validate(sandbox_config, ['build-uid', 'build-gid'])
+        _yaml.node_validate(sandbox_config, ['build-uid', 'build-gid', 'build-os', 'build-arch'])
 
-        return SandboxConfig(self.node_get_member(sandbox_config, int, 'build-uid'),
-                             self.node_get_member(sandbox_config, int, 'build-gid'))
+        return SandboxConfig(
+            int(self.node_subst_member(sandbox_config, 'build-uid')),
+            int(self.node_subst_member(sandbox_config, 'build-gid')),
+            self.node_subst_member(sandbox_config, 'build-os', default=host_os),
+            self.node_subst_member(sandbox_config, 'build-arch', default=host_arch))
 
     # This makes a special exception for the split rules, which
     # elements may extend but whos defaults are defined in the project.
diff --git a/buildstream/sandbox/_config.py b/buildstream/sandbox/_config.py
index 5debe24b2..457f92b3c 100644
--- a/buildstream/sandbox/_config.py
+++ b/buildstream/sandbox/_config.py
@@ -16,7 +16,6 @@
 #
 #  Authors:
 #        Jim MacArthur <jim.macarthur@codethink.co.uk>
-import os
 
 
 # SandboxConfig
@@ -24,9 +23,11 @@ import os
 # A container for sandbox configuration data. We want the internals
 # of this to be opaque, hence putting it in its own private file.
 class SandboxConfig():
-    def __init__(self, build_uid, build_gid):
+    def __init__(self, build_uid, build_gid, build_os=None, build_arch=None):
         self.build_uid = build_uid
         self.build_gid = build_gid
+        self.build_os = build_os
+        self.build_arch = build_arch
 
     # get_unique_key():
     #
@@ -45,10 +46,9 @@ class SandboxConfig():
         # However this should be the right place to support
         # such configurations in the future.
         #
-        operating_system, _, _, _, machine_arch = os.uname()
         unique_key = {
-            'os': operating_system,
-            'arch': machine_arch
+            'os': self.build_os,
+            'arch': self.build_arch
         }
 
         # Avoid breaking cache key calculation with
diff --git a/buildstream/sandbox/_sandboxbwrap.py b/buildstream/sandbox/_sandboxbwrap.py
index 450f1913f..7aa8f31c8 100644
--- a/buildstream/sandbox/_sandboxbwrap.py
+++ b/buildstream/sandbox/_sandboxbwrap.py
@@ -53,6 +53,25 @@ class SandboxBwrap(Sandbox):
         super().__init__(*args, **kwargs)
         self.user_ns_available = kwargs['user_ns_available']
         self.die_with_parent_available = kwargs['die_with_parent_available']
+        self.linux32 = False
+
+        host_os, _, _, _, host_arch = os.uname()
+        config = self._get_config()
+
+        # We can't do builds for another host or architecture except 32 bit on 64 bit
+        if config.build_os != host_os:
+            raise SandboxError("Configured and host OS don't match.")
+        elif config.build_arch != host_arch:
+            if ((config.build_arch == "i686" and host_arch == "x86_64") or
+                (config.build_arch == "armv7l" and host_arch == "aarch64")):
+                # check whether linux32 is available
+                try:
+                    utils.get_host_tool('linux32')
+                    self._linux32 = True
+                except utils.ProgramNotFoundError:
+                    raise SandboxError("Configured and host architecture don't match.")
+            else:
+                raise SandboxError("Configured and host architecture don't match.")
 
     def run(self, command, flags, *, cwd=None, env=None):
         stdout, stderr = self._get_output()
@@ -84,8 +103,14 @@ class SandboxBwrap(Sandbox):
         if cwd is None:
             cwd = '/'
 
+        # start command with linux32 if needed
+        if self.linux32:
+            bwrap_command = [utils.get_host_tool('linux32')]
+        else:
+            bwrap_command = []
+
         # Grab the full path of the bwrap binary
-        bwrap_command = [utils.get_host_tool('bwrap')]
+        bwrap_command += [utils.get_host_tool('bwrap')]
 
         for k, v in env.items():
             bwrap_command += ['--setenv', k, v]