"""read_vtable.py <dump.dmp> <vtable_addr> [num_slots=16]

Read vtable slot pointers from a minidump.
"""
import struct, sys
from minidump.minidumpfile import MinidumpFile


def _ei(v):
    if v is None: return 0
    if hasattr(v, 'value'): return int(v.value)
    return int(v)


def main():
    md = MinidumpFile.parse(sys.argv[1])
    vt = int(sys.argv[2], 0)
    n = int(sys.argv[3]) if len(sys.argv) > 3 else 16

    reader = md.get_reader().get_buffered_reader()
    reader.move(vt)
    buf = reader.read(n * 4)

    print(f"vtable @ 0x{vt:08x}")
    for i in range(n):
        slot = struct.unpack_from("<I", buf, i*4)[0]
        print(f"  +0x{i*4:02x} (slot {i:2d}): 0x{slot:08x}")


if __name__ == "__main__":
    main()