userland: path properties getting nice!

path_properties.py

@@ -0,0 +1,99 @@
+#!/usr/bin/env python3
+
+import os
+
+class PathProperties:
+    '''
+    Encodes properties of userland and baremetal paths.
+    For directories, it applies to all files under the directory.
+    Used to determine how to build and test the examples.
+    '''
+    def __init__(
+        self,
+        **kwargs
+    ):
+        self.properties = {
+            'allowed_archs': None,
+            'exit_status': 0,
+            'interactive': False,
+            'more_than_1s': False,
+            # The path does not generate an executable in itself, e.g.
+            # it only generates intermediate object files.
+            'no_executable': False,
+            # the test receives a signal. We skip those tests for now,
+            # on userland because we are lazy to figure out the exact semantics
+            # of how Python + QEMU + gem5 determine the exit status of signals.
+            'receives_signal': False,
+            'requires_kernel_modules': False,
+        }
+        for key in kwargs:
+            if not key in self.properties:
+                raise ValueError('Unknown key: {}'.format(key))
+        self.properties.update(kwargs)
+
+    def __getitem__(self, key):
+        return self.properties[key]
+
+    def update(self, other):
+        return self.properties.update(other.properties)
+
+    def should_be_tested(self, arch):
+        return \
+            not self['interactive'] and \
+            not self['more_than_1s'] and \
+            not self['no_executable'] and \
+            not self['receives_signal'] and \
+            not self['requires_kernel_modules'] and \
+            (
+                self['allowed_archs'] is None or
+                arch in self['allowed_archs']
+            )
+
+class PrefixTree:
+    def __init__(self, children=None, value=None):
+        if children == None:
+            children = {}
+        self.children = children
+        self.value = value
+
+path_properties_tree = PrefixTree({
+    'arch': PrefixTree({
+        'x86_64': PrefixTree(
+            {
+                'c': PrefixTree({
+                    'ring0.c': PrefixTree(value=PathProperties(receives_signal=True))
+                })
+            },
+            PathProperties(allowed_archs={'x86_64'}),
+        ),
+        'arm': PrefixTree(value=PathProperties(allowed_archs={'arm'})),
+        'aarch64': PrefixTree(value=PathProperties(allowed_archs={'aarch64'})),
+        'empty.S': PrefixTree(value=PathProperties(no_executable=True)),
+        'fail.S': PrefixTree(value=PathProperties(no_executable=True)),
+        'main.c': PrefixTree(value=PathProperties(no_executable=True)),
+    }),
+    'c': PrefixTree({
+        'assert_fail.c': PrefixTree(value=PathProperties(exit_status=1)),
+        'false.c': PrefixTree(value=PathProperties(exit_status=1)),
+        'infinite_loop.c': PrefixTree(value=PathProperties(more_than_1s=True)),
+    }),
+    'kernel_modules': PrefixTree(value=PathProperties(requires_kernel_modules=True)),
+    'linux': PrefixTree(value=PathProperties(requires_kernel_modules=True)),
+    'posix': PrefixTree({
+        'count.c': PrefixTree(value=PathProperties(more_than_1s=True)),
+        'sleep_forever.c': PrefixTree(value=PathProperties(more_than_1s=True)),
+        'virt_to_phys_test.c': PrefixTree(value=PathProperties(more_than_1s=True)),
+    })
+})
+
+def get(test_path):
+    cur_node = path_properties_tree
+    path_properties = PathProperties()
+    for path_component in test_path.split(os.sep):
+        if path_component in cur_node.children:
+            cur_node = cur_node.children[path_component]
+            if cur_node.value is not None:
+                path_properties.update(cur_node.value)
+        else:
+            break
+    return path_properties