linux.py 文件源码

def platformExec(self, cmdline):
        # Very similar to posix, but not
        # quite close enough...
        self.execing = True
        cmdlist = e_cli.splitargs(cmdline)
        os.stat(cmdlist[0])
        pid = os.fork()

        if pid == 0:
            try:
                # Don't use PT_TRACEME -- on some linux (tested on ubuntu)
                # it will cause immediate asignment of ptrace slot to parent
                # without parent having PT_ATTACH'D.... MAKES SYNCHRONIZATION HARD
                # SIGSTOP our self until parent continues us
                os.kill(os.getpid(), signal.SIGSTOP)
                os.execv(cmdlist[0], cmdlist)
            except Exception as e:
                print(e)
            sys.exit(-1)

        # Attach to child. should cause SIGSTOP
        if 0 != v_posix.ptrace(PT_ATTACH, pid, 0, 0):
            raise Exception("PT_ATTACH failed! linux platformExec")

        # Eat all SIGSTOP (or other signal) and break from loop on SIGTRAP.
        # SIGTRAP triggered by execv while PTRACE_ATTACH'd
        while True:
            wpid, status = os.waitpid(pid, os.WUNTRACED)
            if wpid != pid:  # should never happen
                continue
            if os.WIFSTOPPED(status):
                cause = os.WSTOPSIG(status)
                if cause == signal.SIGTRAP:
                    break
                if v_posix.ptrace(v_posix.PT_CONTINUE, pid, 0, 0) != 0:
                    raise Exception("PT_CONTINUE failed! linux platformExec")

        # Do a single step, which will allow a new stop event for the 
        # rest of vtrace to eat up.
        if v_posix.ptrace(v_posix.PT_STEP, pid, 0, 0) != 0:
            raise Exception("PT_CONTINUE failed! linux platformExec")

        self.pthreads = [pid, ]
        self.setMeta("ExeName", self._findExe(pid))
        return pid