wilhelm AST example

example1.py

In [10]: import wilhelm as W
In [11]: W.initialize(W.Feature.PATH)
In [12]: func = W.ast.Function(idaapi.get_screen_ea())

example2.py

In [13]: func.body[0].expr.e_lhs
Out[13]: <wilhelm.ast.DerefExpr at 0x7fe902486470>

example3.py

In [14]: func.body.children.select("IfStmt")
Out[14]: NodeList(...)
In [15]: list(func.body.children.select("IfStmt"))
Out[15]: 
[<wilhelm.ast.IfStmt at 0x7fe8ffe31320>,
 <wilhelm.ast.IfStmt at 0x7fe8ff57f940>]

example4.py

In [16]: def sel(path): return list(func.body.select(path))

example5.py

In [17]: sel("*/BinOpExpr")
Out[17]: 
[<wilhelm.ast.BinOpExpr at 0x7fe8ffe2cb70>,
 <wilhelm.ast.BinOpExpr at 0x7fe8ffe2cb38>,
 ...]

example6.py

In [18]: sel("*/BinOpExpr.e_lhs/LocalVarExpr{name = 'fourcc2'}")
Out[18]: 
[<wilhelm.ast.LocalVarExpr at 0x7fe8ffdadf60>,
 <wilhelm.ast.LocalVarExpr at 0x7fe8ffdb2198>,
 ...]

example7.py

In [19]: sel("*/BinOpExpr[.e_lhs/LocalVarExpr{name = 'fourcc2'}].e_rhs/NumExpr")
Out[19]: 
[<wilhelm.ast.NumExpr at 0x7fe8ffdadf98>,
 <wilhelm.ast.NumExpr at 0x7fe8ffdb21d0>,
 ...]

example8.py

def switch_to_char(num):
    nf = idaapi.number_format_t()
    nf.opnum = num.hexrays_item.n.nf.opnum
    nf.flags = idaapi.char_flag()
    nf.props = idaapi.NF_FIXED
    idaapi.user_numforms_insert(
        num.parent_func.hx_func.numforms, 
        idaapi.operand_locator_t(num.ea,
                                 ord(num.hexrays_item.n.nf.opnum)),
        nf)
    num.parent_func.hx_func.save_user_numforms()

example9.py

In [20]: for num in sel("*/BinOpExpr[.e_lhs/LocalVarExpr{name = 'fourcc2'}].e_rhs/NumExpr"): 
    ...:     switch_to_char(num)