xref: /openbsd-src/gnu/llvm/lldb/examples/python/shadow.py (revision f6aab3d83b51b91c24247ad2c2573574de475a82)
1*be691f3bSpatrick#!/usr/bin/env python
2061da546Spatrick
3061da546Spatrickimport lldb
4061da546Spatrickimport shlex
5061da546Spatrick
6061da546Spatrick
7061da546Spatrick@lldb.command("shadow")
8061da546Spatrickdef check_shadow_command(debugger, command, exe_ctx, result, dict):
9061da546Spatrick    '''Check the currently selected stack frame for shadowed variables'''
10061da546Spatrick    process = exe_ctx.GetProcess()
11061da546Spatrick    state = process.GetState()
12061da546Spatrick    if state != lldb.eStateStopped:
13061da546Spatrick        print("process must be stopped, state is %s" % lldb.SBDebugger.StateAsCString(
14061da546Spatrick            state), file=result)
15061da546Spatrick        return
16061da546Spatrick    frame = exe_ctx.GetFrame()
17061da546Spatrick    if not frame:
18061da546Spatrick        print("invalid frame", file=result)
19061da546Spatrick        return
20061da546Spatrick    # Parse command line args
21061da546Spatrick    command_args = shlex.split(command)
22061da546Spatrick    # TODO: add support for using arguments that are passed to this command...
23061da546Spatrick
24061da546Spatrick    # Make a dictionary of variable name to "SBBlock and SBValue"
25061da546Spatrick    shadow_dict = {}
26061da546Spatrick
27061da546Spatrick    num_shadowed_variables = 0
28061da546Spatrick    # Get the deepest most block from the current frame
29061da546Spatrick    block = frame.GetBlock()
30061da546Spatrick    # Iterate through the block and all of its parents
31061da546Spatrick    while block.IsValid():
32061da546Spatrick        # Get block variables from the current block only
33061da546Spatrick        block_vars = block.GetVariables(frame, True, True, True, 0)
34061da546Spatrick        # Iterate through all variables in the current block
35061da546Spatrick        for block_var in block_vars:
36061da546Spatrick            # Since we can have multiple shadowed variables, we our variable
37061da546Spatrick            # name dictionary to have an array or "block + variable" pairs so
38061da546Spatrick            # We can correctly print out all shadowed variables and whow which
39061da546Spatrick            # blocks they come from
40061da546Spatrick            block_var_name = block_var.GetName()
41061da546Spatrick            if block_var_name in shadow_dict:
42061da546Spatrick                shadow_dict[block_var_name].append(block_var)
43061da546Spatrick            else:
44061da546Spatrick                shadow_dict[block_var_name] = [block_var]
45061da546Spatrick        # Get the parent block and continue
46061da546Spatrick        block = block.GetParent()
47061da546Spatrick
48061da546Spatrick    num_shadowed_variables = 0
49061da546Spatrick    if shadow_dict:
50061da546Spatrick        for name in shadow_dict.keys():
51061da546Spatrick            shadow_vars = shadow_dict[name]
52061da546Spatrick            if len(shadow_vars) > 1:
53061da546Spatrick                print('"%s" is shadowed by the following declarations:' % (name))
54061da546Spatrick                num_shadowed_variables += 1
55061da546Spatrick                for shadow_var in shadow_vars:
56061da546Spatrick                    print(str(shadow_var.GetDeclaration()), file=result)
57061da546Spatrick    if num_shadowed_variables == 0:
58061da546Spatrick        print('no variables are shadowed', file=result)
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