1 files changed, 115 insertions, 0 deletions
diff --git a/Tools/c-analyzer/c_parser/parser/_common.py b/Tools/c-analyzer/c_parser/parser/_common.py
new file mode 100644
index 00000000000..40c36039f3f
--- /dev/null
+++ b/Tools/c-analyzer/c_parser/parser/_common.py
@@ -0,0 +1,115 @@
+import re
+
+from ._regexes import (
+    _ind,
+    STRING_LITERAL,
+    VAR_DECL as _VAR_DECL,
+)
+
+
+def log_match(group, m):
+    from . import _logger
+    _logger.debug(f'matched <{group}> ({m.group(0)})')
+
+
+#############################
+# regex utils
+
+def set_capture_group(pattern, group, *, strict=True):
+    old = f'(?:  # <{group}>'
+    if strict and f'(?:  # <{group}>' not in pattern:
+        raise ValueError(f'{old!r} not found in pattern')
+    return pattern.replace(old, f'(  # <{group}>', 1)
+
+
+def set_capture_groups(pattern, groups, *, strict=True):
+    for group in groups:
+        pattern = set_capture_group(pattern, group, strict=strict)
+    return pattern
+
+
+#############################
+# syntax-related utils
+
+_PAREN_RE = re.compile(rf'''
+    (?:
+        (?:
+            [^'"()]*
+            {_ind(STRING_LITERAL, 3)}
+         )*
+        [^'"()]*
+        (?:
+            ( [(] )
+            |
+            ( [)] )
+         )
+     )
+    ''', re.VERBOSE)
+
+
+def match_paren(text, depth=0):
+    pos = 0
+    while (m := _PAREN_RE.match(text, pos)):
+        pos = m.end()
+        _open, _close = m.groups()
+        if _open:
+            depth += 1
+        else:  # _close
+            depth -= 1
+            if depth == 0:
+                return pos
+    else:
+        raise ValueError(f'could not find matching parens for {text!r}')
+
+
+VAR_DECL = set_capture_groups(_VAR_DECL, (
+    'STORAGE',
+    'TYPE_QUAL',
+    'TYPE_SPEC',
+    'DECLARATOR',
+    'IDENTIFIER',
+    'WRAPPED_IDENTIFIER',
+    'FUNC_IDENTIFIER',
+))
+
+
+def parse_var_decl(decl):
+    m = re.match(VAR_DECL, decl, re.VERBOSE)
+    (storage, typequal, typespec, declarator,
+     name,
+     wrappedname,
+     funcptrname,
+     ) = m.groups()
+    if name:
+        kind = 'simple'
+    elif wrappedname:
+        kind = 'wrapped'
+        name = wrappedname
+    elif funcptrname:
+        kind = 'funcptr'
+        name = funcptrname
+    else:
+        raise NotImplementedError
+    abstract = declarator.replace(name, '')
+    vartype = {
+        'storage': storage,
+        'typequal': typequal,
+        'typespec': typespec,
+        'abstract': abstract,
+    }
+    return (kind, name, vartype)
+
+
+#############################
+# parser state utils
+
+# XXX Drop this or use it!
+def iter_results(results):
+    if not results:
+        return
+    if callable(results):
+        results = results()
+
+    for result, text in results():
+        if result:
+            yield result, text