Coverage for wasmtime/_error.py: 95%

1from ctypes import byref, POINTER, c_int 

2from . import _ffi as ffi 

3import ctypes 

4from typing import Optional 

5from wasmtime import Managed 

6 

7 

8class WasmtimeError(Exception, Managed["ctypes._Pointer[ffi.wasmtime_error_t]"]): 

9 __message: Optional[str] 

10 

11 def __init__(self, message: str): 

12 self.__message = message 

13 self._set_ptr(ffi.wasmtime_error_new(message.encode('utf-8'))) 

14 

15 def _delete(self, ptr: "ctypes._Pointer[ffi.wasmtime_error_t]") -> None: 

16 ffi.wasmtime_error_delete(ptr) 

17 

18 @classmethod 

19 def _from_ptr(cls, ptr: "ctypes._Pointer[ffi.wasmtime_error_t]") -> 'WasmtimeError': 

20 from . import _ffi as ffi 

21 if not isinstance(ptr, POINTER(ffi.wasmtime_error_t)): 

22 raise TypeError("wrong pointer type") 

23 

24 exit_code = c_int(0) 

25 if ffi.wasmtime_error_exit_status(ptr, byref(exit_code)): 

26 exit_trap: ExitTrap = ExitTrap.__new__(ExitTrap) 

27 exit_trap._set_ptr(ptr) 

28 exit_trap.__message = None 

29 exit_trap.code = exit_code.value 

30 return exit_trap 

31 

32 err: WasmtimeError = cls.__new__(cls) 

33 err._set_ptr(ptr) 

34 err.__message = None 

35 return err 

36 

37 def __str__(self) -> str: 

38 if self.__message: 

39 return self.__message 

40 message_vec = ffi.wasm_byte_vec_t() 

41 ffi.wasmtime_error_message(self.ptr(), byref(message_vec)) 

42 message = ffi.to_str(message_vec) 

43 ffi.wasm_byte_vec_delete(byref(message_vec)) 

44 return message 

45 

46 

47class ExitTrap(WasmtimeError): 

48 """ 

49 A special type of `WasmtimeError` which represents the process exiting via 

50 WASI's `proc_exit` function call. 

51 

52 Whenever a WASI program exits via `proc_exit` a trap is raised, but the 

53 trap will have this type instead of `WasmtimeError`, so you can catch just 

54 this type instead of all traps (if desired). Exit traps have a `code` 

55 associated with them which is the exit code provided at exit. 

56 

57 Note that `ExitTrap` is a subclass of `WasmtimeError`, so if you catch a 

58 trap you'll also catch `ExitTrap`. 

59 """ 

60 code: int 

61 pass