Python 中用 libClang 进行源码静态分析

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import clang.cindex as cindex
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from pathlib import Path
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# folder of libclang.so, found in step 0.5
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cindex.Config.library_path = "/usr/lib"
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file = Path("test.c")
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parser = cindex.Index.create()
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tu = parser.parse(file.absolute())
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for node in tu.cursor.get_children():
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    node: cindex.Cursor = node # for type hint
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    if not str(node.location.file).endswith(".c"):
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        # if no need to dive into header files
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        continue
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    print(node.kind, node.spelling, node.extent.start)

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def find_function_name_in_CALL_EXPR(node: cindex.Cursor) -> str:
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    assert node.kind == cindex.CursorKind.CALL_EXPR
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    tmp = next(node.get_children())
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    if tmp.kind == cindex.CursorKind.DECL_REF_EXPR:
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        DEBUG(f"Fall back to DECL_REF_EXPR {tmp.spelling} {tmp.kind} {tmp.extent.start}")
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        name = tmp.spelling
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    else:
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        childs = [c for c in tmp.get_children()]
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        # panic_if_not(len(childs) == 1, childs)
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        if len(childs) != 1:
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            return None
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        if childs[0].kind != cindex.CursorKind.DECL_REF_EXPR:
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            DEBUG(f"(Skip indirect calling)UB in parse {childs[0].spelling} {childs[0].kind} {childs[0].extent.start}")
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            return None
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        name = childs[0].spelling
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    return name

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def parse_function(node: cindex.Cursor) -> set[str]:
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    assert node.kind == cindex.CursorKind.FUNCTION_DECL
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    dep_funcs = set()
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    func_body = [n for n in node.get_children() if n.kind == cindex.CursorKind.COMPOUND_STMT]
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    if len(func_body) == 0:
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        # Can be forward-decline
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        DEBUG(f"not found body, can be forward-decline {node.spelling}")
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        return dep_funcs
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    assert len(func_body) == 1
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    func_body: cindex.Cursor = func_body[0]
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    for child in func_body.walk_preorder():
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        child: cindex.Cursor = child # for type hint
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        if child.kind == cindex.CursorKind.CALL_EXPR:
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            name = find_function_name_in_CALL_EXPR(child)
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            dep_funcs.add(name)
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    return dep_funcs