src/openpower/syscalls/__init__.py

   1 import ctypes
   2 import functools
   3 import inspect
   4 import json
   5 import pathlib
   6
   7
   8 class Dispatcher:
   9     def __init__(self, guest, host, logger=None, table=None):
  10         if table is None:
  11             path = pathlib.Path(inspect.getfile(self.__class__))
  12             path = (path.parent / "syscalls.json")
  13             with open(path, "r", encoding="UTF-8") as stream:
  14                 table = json.load(stream)
  15         if not isinstance(table, dict):
  16             raise ValueError("dict instance expected")
  17         if "sysnums" not in table or "sysargs" not in table:
  18             raise ValueError("sysnums and sysargs keys expected")
  19
  20         if logger is None:
  21             logger = lambda *args, **kwargs: None
  22
  23         def i386(sysnums):
  24             yield from sysnums["x86-32"]["i386"].items()
  25
  26         def amd64(sysnums):
  27             yield from sysnums["x86-64"]["common"].items()
  28             yield from sysnums["x86-64"]["64"].items()
  29
  30         def ppc(sysnums):
  31             yield from sysnums["ppc"]["nospu"].items()
  32             yield from sysnums["ppc"]["common"].items()
  33             yield from sysnums["ppc"]["32"].items()
  34
  35         def ppc64(sysnums):
  36             yield from sysnums["ppc"]["nospu"].items()
  37             yield from sysnums["ppc"]["common"].items()
  38             yield from sysnums["ppc"]["64"].items()
  39
  40         arch = {
  41             "i386": i386,
  42             "amd64": amd64,
  43             "ppc": ppc,
  44             "ppc64": ppc64,
  45         }
  46         sysnums = table["sysnums"]
  47         sysargs = table["sysargs"]
  48
  49         self.__guest = dict(arch[guest](sysnums))
  50         self.__host = dict(arch[host](sysnums))
  51         self.__parameters = sysargs
  52         self.__logger = logger
  53         self.__libc = ctypes.CDLL(None)
  54
  55         return super().__init__()
  56
  57     def __getattr__(self, entry):
  58         if entry.startswith("compat_sys_"):
  59             identifier = entry[len("compat_sys_"):]
  60         elif entry.startswith("sys_"):
  61             identifier = entry[len("sys_"):]
  62         else:
  63             raise AttributeError(entry)
  64
  65         if entry not in self.__parameters:
  66             raise AttributeError(entry)
  67
  68         if identifier not in self.__guest:
  69             raise AttributeError(entry)
  70         identifier = int(self.__guest[identifier])
  71
  72         def syscall(identifier, *arguments):
  73             parameters = tuple(self.__parameters[entry].items())
  74             if len(arguments) != len(parameters):
  75                 raise ValueError("conflict between arguments and parameters")
  76
  77             identifier = str(identifier)
  78             identifier = self.__guest[identifier][0]
  79             guest = int(self.__guest[identifier])
  80             host = int(self.__host[identifier])
  81             self.__logger(f"{identifier} {guest} => {host}")
  82             for index in range(len(arguments)):
  83                 value = arguments[index]
  84                 if not isinstance(value, int):
  85                     raise ValueError("integer argument expected")
  86                 name = parameters[index][0]
  87                 ctype = parameters[index][1]
  88                 self.__logger(f"    0x{value:016x} {name} ({ctype})")
  89
  90             syscall = self.__libc.syscall
  91             syscall.restype = ctypes.c_long
  92             syscall.argtypes = ([ctypes.c_long] * len(arguments))
  93
  94             return int(syscall(ctypes.c_ulong(host)))
  95
  96         return functools.partial(syscall, identifier)
  97
  98     def __call__(self, identifier, *arguments):
  99         if not isinstance(identifier, int):
 100             raise ValueError(identifier)
 101
 102         identifier = str(identifier)
 103         entry = self.__guest[identifier][1][0]
 104         syscall = getattr(self, entry)
 105
 106         return syscall(*arguments)