[PATCH v5 01/15] docs: conf.py: properly handle include and exclude patterns

When one does:
	make SPHINXDIRS="foo" htmldocs

All patterns would be relative to Documentation/foo, which
causes the include/exclude patterns like:

	include_patterns = [
		...
		f'foo/*.{ext}',
	]

to break. This is not what it is expected. Address it by
adding a logic to dynamically adjust the pattern when
SPHINXDIRS is used.

That allows adding parsers for other file types.

Signed-off-by: Mauro Carvalho Chehab <[email protected]>
---
 Documentation/conf.py | 52 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 48 insertions(+), 4 deletions(-)

diff --git a/Documentation/conf.py b/Documentation/conf.py
index 12de52a2b17e..e887c1b786a4 100644
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -17,6 +17,54 @@ import os
 import sphinx
 import shutil
 
+# Location of Documentation/ directory
+doctree = os.path.abspath('.')
+
+# List of patterns that don't contain directory names, in glob format.
+include_patterns = ['**.rst']
+exclude_patterns = []
+
+# List of patterns that contain directory names in glob format.
+dyn_include_patterns = []
+dyn_exclude_patterns = ['output']
+
+# Properly handle include/exclude patterns
+# ----------------------------------------
+
+def setup(app):
+    """
+    On Sphinx, all directories are relative to what it is passed as
+    SOURCEDIR parameter for sphinx-build. Due to that, all patterns
+    that have directory names on it need to be dynamically set, after
+    converting them to a relative patch.
+
+    As Sphinx doesn't include any patterns outside SOURCEDIR, we should
+    exclude relative patterns that start with "../".
+    """
+
+    sourcedir = app.srcdir  # full path to the source directory
+    builddir = os.environ.get("BUILDDIR")
+
+    # setup include_patterns dynamically
+    for p in dyn_include_patterns:
+        full = os.path.join(doctree, p)
+
+        rel_path = os.path.relpath(full, start = app.srcdir)
+        if rel_path.startswith("../"):
+            continue
+
+        app.config.include_patterns.append(rel_path)
+
+    # setup exclude_patterns dynamically
+    for p in dyn_exclude_patterns:
+        full = os.path.join(doctree, p)
+
+        rel_path = os.path.relpath(full, start = app.srcdir)
+        if rel_path.startswith("../"):
+            continue
+
+        app.config.exclude_patterns.append(rel_path)
+
 # helper
 # ------
 
@@ -219,10 +267,6 @@ language = 'en'
 # Else, today_fmt is used as the format for a strftime call.
 #today_fmt = '%B %d, %Y'
 
-# List of patterns, relative to source directory, that match files and
-# directories to ignore when looking for source files.
-exclude_patterns = ['output']
-
 # The reST default role (used for this markup: `text`) to use for all
 # documents.
 #default_role = None
-- 
2.49.0