1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
|
"""
Function get_errno(): get the current errno value.
Try different implementations:
- ctypes_support.get_errno() function
- __errno_location_sym symbol from the C library
- PyErr_SetFromErrno() from the C Python API
"""
get_errno = None
try:
from ctypes_support import get_errno
except ImportError:
pass
if not get_errno:
from ctypes import POINTER, c_int
def _errno_location():
"""
Try to get errno integer from libc using __errno_location_sym function.
This function is specific to OS with "libc.so.6" and may fails for
thread-safe libc.
"""
from ctypes import cdll
try:
libc = cdll.LoadLibrary("libc.so.6")
except OSError:
# Unable to open libc dynamic library
return None
try:
__errno_location = libc.__errno_location_sym
except AttributeError:
# libc doesn't have __errno_location
return None
__errno_location.restype = POINTER(c_int)
return __errno_location()[0]
errno = _errno_location()
if errno is not None:
def get_errno():
# pyflakes warn about "undefined name",
# but that's wrong: errno is defined!
return errno
else:
del errno
if not get_errno:
from ctypes import pythonapi, py_object
# Function from pypy project:
# File pypy/dist/pypy/rpython/rctypes/aerrno.py
def _pythonapi_geterrno():
"""
Read errno using Python C API: raise an exception with PyErr_SetFromErrno
and then read error code 'errno'.
This function may raise an RuntimeError.
"""
try:
pythonapi.PyErr_SetFromErrno(py_object(OSError))
except OSError as err:
return err.errno
else:
raise RuntimeError("get_errno() is unable to get error code")
get_errno = _pythonapi_geterrno
__all__ = ["get_errno"]
|
