Coverage for wasmtime/

1from ctypes import POINTER, Structure, Union, addressof, byref, cdll, string_at

2from ctypes import c_double, c_float, c_int32, c_int64, c_uint8

3from pathlib import Path

4import ctypes

5import sys

6import platform

7import typing

9if sys.maxsize <= 2**32:

10 raise RuntimeError("wasmtime only works on 64-bit platforms right now")

12sys_platform = sys.platform

14# For Python versions <=3.12. 3.13+ supports PEP 738 and uses sys.platform

15if hasattr(sys, 'getandroidapilevel'):

16 sys_platform = 'android'

18if sys_platform == 'linux' or sys_platform == 'android':

19 libname = '_libwasmtime.so'

20elif sys_platform == 'win32':

21 libname = '_wasmtime.dll'

22elif sys_platform == 'darwin':

23 libname = '_libwasmtime.dylib'

24else:

25 raise RuntimeError("unsupported platform `{}` for wasmtime".format(sys_platform))

28machine = platform.machine()

29if machine == 'AMD64':

30 machine = 'x86_64'

31if machine == 'arm64' or machine == 'ARM64':

32 machine = 'aarch64'

33if machine != 'x86_64' and machine != 'aarch64':

34 raise RuntimeError("unsupported architecture for wasmtime: {}".format(machine))

36filename = Path(__file__).parent / (sys_platform + '-' + machine) / libname

38dll = cdll.LoadLibrary(str(filename))

40WASM_I32 = c_uint8(0)

41WASM_I64 = c_uint8(1)

42WASM_F32 = c_uint8(2)

43WASM_F64 = c_uint8(3)

44WASM_ANYREF = c_uint8(128)

45WASM_FUNCREF = c_uint8(129)

46# WASM_V128 = c_uint8(4)

48WASMTIME_I32 = c_uint8(0)

49WASMTIME_I64 = c_uint8(1)

50WASMTIME_F32 = c_uint8(2)

51WASMTIME_F64 = c_uint8(3)

52WASMTIME_V128 = c_uint8(4)

53WASMTIME_FUNCREF = c_uint8(5)

54WASMTIME_EXTERNREF = c_uint8(6)

56WASM_CONST = c_uint8(0)

57WASM_VAR = c_uint8(1)

59WASMTIME_EXTERN_FUNC = c_uint8(0)

60WASMTIME_EXTERN_GLOBAL = c_uint8(1)

61WASMTIME_EXTERN_TABLE = c_uint8(2)

62WASMTIME_EXTERN_MEMORY = c_uint8(3)

63WASMTIME_EXTERN_SHAREDMEMORY = c_uint8(4)

64WASMTIME_EXTERN_TAG = c_uint8(5)

66WASMTIME_FUNCREF_NULL = (1 << 64) - 1

68WASMTIME_COMPONENT_ITEM_COMPONENT = c_uint8(0)

69WASMTIME_COMPONENT_ITEM_COMPONENT_INSTANCE = c_uint8(1)

70WASMTIME_COMPONENT_ITEM_MODULE = c_uint8(2)

71WASMTIME_COMPONENT_ITEM_COMPONENT_FUNC = c_uint8(3)

72WASMTIME_COMPONENT_ITEM_RESOURCE = c_uint8(4)

73WASMTIME_COMPONENT_ITEM_CORE_FUNC = c_uint8(5)

74WASMTIME_COMPONENT_ITEM_TYPE = c_uint8(6)

76WASMTIME_COMPONENT_VALTYPE_BOOL = c_uint8(0)

77WASMTIME_COMPONENT_VALTYPE_S8 = c_uint8(1)

78WASMTIME_COMPONENT_VALTYPE_S16 = c_uint8(2)

79WASMTIME_COMPONENT_VALTYPE_S32 = c_uint8(3)

80WASMTIME_COMPONENT_VALTYPE_S64 = c_uint8(4)

81WASMTIME_COMPONENT_VALTYPE_U8 = c_uint8(5)

82WASMTIME_COMPONENT_VALTYPE_U16 = c_uint8(6)

83WASMTIME_COMPONENT_VALTYPE_U32 = c_uint8(7)

84WASMTIME_COMPONENT_VALTYPE_U64 = c_uint8(8)

85WASMTIME_COMPONENT_VALTYPE_F32 = c_uint8(9)

86WASMTIME_COMPONENT_VALTYPE_F64 = c_uint8(10)

87WASMTIME_COMPONENT_VALTYPE_CHAR = c_uint8(11)

88WASMTIME_COMPONENT_VALTYPE_STRING = c_uint8(12)

89WASMTIME_COMPONENT_VALTYPE_LIST = c_uint8(13)

90WASMTIME_COMPONENT_VALTYPE_RECORD = c_uint8(14)

91WASMTIME_COMPONENT_VALTYPE_TUPLE = c_uint8(15)

92WASMTIME_COMPONENT_VALTYPE_VARIANT = c_uint8(16)

93WASMTIME_COMPONENT_VALTYPE_ENUM = c_uint8(17)

94WASMTIME_COMPONENT_VALTYPE_OPTION = c_uint8(18)

95WASMTIME_COMPONENT_VALTYPE_RESULT = c_uint8(19)

96WASMTIME_COMPONENT_VALTYPE_FLAGS = c_uint8(20)

97WASMTIME_COMPONENT_VALTYPE_OWN = c_uint8(21)

98WASMTIME_COMPONENT_VALTYPE_BORROW = c_uint8(22)

99WASMTIME_COMPONENT_VALTYPE_FUTURE = c_uint8(23)

100WASMTIME_COMPONENT_VALTYPE_STREAM = c_uint8(24)

101WASMTIME_COMPONENT_VALTYPE_ERROR_CONTEXT = c_uint8(25)

102

103WASMTIME_COMPONENT_BOOL = c_uint8(0)

104WASMTIME_COMPONENT_S8 = c_uint8(1)

105WASMTIME_COMPONENT_U8 = c_uint8(2)

106WASMTIME_COMPONENT_S16 = c_uint8(3)

107WASMTIME_COMPONENT_U16 = c_uint8(4)

108WASMTIME_COMPONENT_S32 = c_uint8(5)

109WASMTIME_COMPONENT_U32 = c_uint8(6)

110WASMTIME_COMPONENT_S64 = c_uint8(7)

111WASMTIME_COMPONENT_U64 = c_uint8(8)

112WASMTIME_COMPONENT_F32 = c_uint8(9)

113WASMTIME_COMPONENT_F64 = c_uint8(10)

114WASMTIME_COMPONENT_CHAR = c_uint8(11)

115WASMTIME_COMPONENT_STRING = c_uint8(12)

116WASMTIME_COMPONENT_LIST = c_uint8(13)

117WASMTIME_COMPONENT_RECORD = c_uint8(14)

118WASMTIME_COMPONENT_TUPLE = c_uint8(15)

119WASMTIME_COMPONENT_VARIANT = c_uint8(16)

120WASMTIME_COMPONENT_ENUM = c_uint8(17)

121WASMTIME_COMPONENT_OPTION = c_uint8(18)

122WASMTIME_COMPONENT_RESULT = c_uint8(19)

123WASMTIME_COMPONENT_FLAGS = c_uint8(20)

124WASMTIME_COMPONENT_RESOURCE = c_uint8(21)

125

126class wasm_ref_t(Structure):

127 pass

128

129

130class wasm_val_union(Union):

131 _fields_ = [

132 ("i32", c_int32),

133 ("i64", c_int64),

134 ("f32", c_float),

135 ("f64", c_double),

136 ("ref", POINTER(wasm_ref_t)),

137 ]

138

139 i32: int

140 i64: int

141 f32: float

142 f64: float

143 ref: "typing.Union[ctypes._Pointer[wasm_ref_t], None]"

144

145

146class wasm_val_t(Structure):

147 _fields_ = [("kind", c_uint8), ("of", wasm_val_union)]

148

149 kind: int

150 of: wasm_val_union

151

152

153from ._bindings import * # noqa

154

155

156def to_bytes(vec: wasm_byte_vec_t) -> bytearray:

157 ty = c_uint8 * vec.size

158 return bytearray(ty.from_address(addressof(vec.data.contents)))

159

160def to_str(vec: wasm_byte_vec_t) -> str:

161 return to_bytes(vec).decode("utf-8")

162

163

164def to_str_raw(ptr: "ctypes._Pointer", size: int) -> str:

165 return string_at(ptr, size).decode("utf-8")

166

167

168def str_to_capi(s: str) -> wasm_byte_vec_t:

169 if not isinstance(s, str):

170 raise TypeError("expected a string")

171 return bytes_to_capi(s.encode('utf8'))

172

173def bytes_to_capi(s: typing.Union[bytes, bytearray]) -> wasm_byte_vec_t:

174 if not isinstance(s, (bytes, bytearray)):

175 raise TypeError("expected bytes or bytearray")

176 vec = wasm_byte_vec_t()

177 wasm_byte_vec_new_uninitialized(byref(vec), len(s))

178 buf = (c_uint8 * len(s)).from_buffer_copy(s)

179 ctypes.memmove(vec.data, buf, len(s))

180 return vec

181

182def take_pointer(structure: ctypes._Pointer, field_name: str) -> ctypes._Pointer:

183 """

184 Moral equivalent of `mem::replace(&mut structure.field_name, NULL)`

185

186 Ctypes explicitly documents "Surprises" which includes, for example:

187

188 import ctypes

189

190 class A(ctypes.Structure):

191 _fields_ = [("x", ctypes.POINTER(ctypes.c_int))]

192

193 x_p = ctypes.pointer(ctypes.c_int(3))

194 a = A(x_p)

195 x = a.x

196

197 print(x.contents)

198 a.x = None

199 print(x.contents)

200

201 This program will segfault on the second access. It turns out that `x = a.x`

202 is still actually a pointer into the original structure, and `a.x`

203 overwrites that field so accessing `x` later accesses null memory. This

204 method is an attempt to work around this surprising behavior and actually

205 read the field from a structure and replace it with null.

206

207 I'll be honest I just sat through a 3 hour flight, a 5 hour layover, a 9

208 hour flight, 1 hour train ride, and I'm sitting in a hotel lobby for

209 another 5 hours. That's my state of mind writing this up, so please

210 draw conclusions about this method as appropriate.

211 """

212 field = getattr(structure, field_name)

213 assert(isinstance(field, ctypes._Pointer))

214 ret = ctypes.cast(ctypes.addressof(field.contents), ctypes.POINTER(field._type_))

215 setattr(structure, field_name, None)

216 return ret

Coverage for wasmtime/_ffi.py: 91%

137 statements