doc: update release branch with new docs

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>

doc/extensions/eager_only.py

@@ -30,7 +30,7 @@ class EagerOnly(sphinx.directives.other.Only):
         # Evaluate the condition eagerly, and if false return no nodes right away
         env = self.state.document.settings.env
         env.app.builder.tags.add('TRUE')
-        #print(repr(self.arguments[0]))
+
         if not env.app.builder.tags.eval_condition(self.arguments[0]):
             return []
 
@@ -43,3 +43,13 @@ class EagerOnly(sphinx.directives.other.Only):
 
 def setup(app):
     directives.register_directive('only', EagerOnly)
+
+    # The tags.add call above is setting tags.tags['TRUE'] = True.
+    # The operation is idempotent and will have taken effect before
+    # the next eval_condition() which may rely on it so this is thread
+    # safe both for read and writes (all other operations are local to
+    # the local nodes variable).
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True,
+        }

doc/extensions/link_roles.py

@@ -0,0 +1,62 @@
+# Copyright (c) 2019 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+
+# based on http://protips.readthedocs.io/link-roles.html
+
+from __future__ import print_function
+from __future__ import unicode_literals
+import re
+import os
+import os.path
+from os import path
+import subprocess
+from docutils import nodes
+
+
+def run_cmd_get_output(cmd):
+    try:
+        with open(os.devnull, 'w') as devnull:
+            output = subprocess.check_output(cmd, stderr=devnull, shell=True).strip()
+    except subprocess.CalledProcessError as e:
+        output = e.output.decode('ascii')
+
+    return output
+
+def get_github_rev():
+    tag = run_cmd_get_output('git describe --exact-match')
+    if tag:
+        return tag.decode("utf-8")
+    else:
+        return 'master'
+
+
+def setup(app):
+    rev = get_github_rev()
+
+    baseurl = 'https://github.com/projectacrn/acrn-hypervisor'
+
+    app.add_role('acrn_file', autolink('{}/blob/{}/%s'.format(baseurl, rev)))
+    app.add_role('acrn_raw', autolink('{}/raw/{}/%s'.format(baseurl, rev)))
+
+    # The role just creates new nodes based on information in the
+    # arguments; its behavior doesn't depend on any other documents.
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True,
+    }
+
+
+def autolink(pattern):
+    def role(name, rawtext, text, lineno, inliner, options={}, content=[]):
+        m = re.search(r'(.*)\s*<(.*)>', text)
+        if m:
+            link_text = m.group(1)
+            link = m.group(2)
+        else:
+            link_text = text
+            link = text
+        url = pattern % (link,)
+        node = nodes.reference(rawtext, link_text, refuri=url, **options)
+        return [node], []
+    return role