def attach(self, pid):
self.running = True
self.pid = pid
self.task = debug.task_for_pid(self.pid)
self.is64 = debug.is_64_bit(self.pid)
debug.ptrace_attach(pid)
status = os.waitpid(self.pid, 0)[1]
self.running = False
def start(self, args):
assert self.pid is None, "already tracing a program."
self.running = True
self.pid = os.fork()
if self.pid:
status = os.waitpid(self.pid, 0)[1]
self.task = debug.task_for_pid(self.pid)
self.is64 = debug.is_64_bit(self.pid)
self.running = False
else:
debug.ptrace_trace_me()
os.execv(args[0], args)
def run(self):
pc_register_name = self.general_register_prefix + 'ip'
assert not self.running
self.threads = debug.task_threads(self.task)
status = self.run_and_wait()
while os.WIFSTOPPED(status):
if os.WSTOPSIG(status) != signal.SIGTRAP:
# Send all non-trap signals to the child.
status = self.run_and_wait(signal=os.WSTOPSIG(status))
continue
try:
state = self.general_register_state
except OSError:
# This condition occurs when a process performs an exec
# call across bit-sizes. Everything is still a bit crazy,
# though and maybe it should just crash until I find a
# better way to detect "the program just changed".
self.is64 = debug.is_64_bit(self.pid)
pc_register_name = self.general_register_prefix + 'ip'
state = self.general_register_state
pc = getattr(state, pc_register_name)
if pc - 1 in self.breakpoints:
setattr(state, pc_register_name, pc - 1)
address = pc - 1
breakpoint = self.breakpoints[address]
breakpoint.callback(self)
# step past the breakpoint, then reinsert it:
debug.thread_set_state(self.threads[0], state)
old_value = breakpoint.old_value
debug.vm_write_wrapper(self.task, address, old_value)
self.run_and_wait(step=True)
if breakpoint.remove_once_hit():
del self.breakpoints[address]
else:
debug.vm_write_wrapper(self.task, address, '\xCC')
status = self.run_and_wait()