def test_stop_sampling(self):
if not self.plain:
skip("unreliable test except on CPython without -A")
import os
import _vmprof
tmpfile = open(self.tmpfilename, 'wb')
native = 1
def f():
import sys
import math
j = sys.maxsize
for i in range(500):
j = math.sqrt(j)
_vmprof.enable(tmpfile.fileno(), 0.01, 0, native, 0, 0)
# get_vmprof_stack() always returns 0 here!
# see vmprof_common.c and assume RPYTHON_LL2CTYPES is defined!
f()
fileno = _vmprof.stop_sampling()
pos = os.lseek(fileno, 0, os.SEEK_CUR)
f()
pos2 = os.lseek(fileno, 0, os.SEEK_CUR)
assert pos == pos2
_vmprof.start_sampling()
f()
fileno = _vmprof.stop_sampling()
pos3 = os.lseek(fileno, 0, os.SEEK_CUR)
assert pos3 > pos
_vmprof.disable()
def disable():
try:
# fish the file descriptor that is still open!
fileno = _vmprof.stop_sampling()
if fileno >= 0:
_vmprof.flush_buffers()
# TODO does fileobj leak the fd? I dont think so, but need to check
fileobj = FdWrapper(fileno)
l = LogReaderDumpNative(fileobj, LogReaderState())
l.read_all()
_vmprof.write_all_code_objects(l.dedup)
_vmprof.disable()
except IOError as e:
raise Exception("Error while writing profile: " + str(e))
