C++ DNBError类代码示例

//----------------------------------------------------------------------
// MachTask::Resume
//----------------------------------------------------------------------
kern_return_t
MachTask::Resume()
{
    struct task_basic_info task_info;
    task_t task = TaskPort();
	if (task == TASK_NULL)
		return KERN_INVALID_ARGUMENT;

    DNBError err;
    err = BasicInfo(task, &task_info);

    if (err.Success())
    {
		// task_resume isn't counted like task_suspend calls are, are, so if the 
		// task is not suspended, don't try and resume it since it is already 
		// running
		if (task_info.suspend_count > 0)
        {
            err = ::task_resume (task);
            if (DNBLogCheckLogBit(LOG_TASK) || err.Fail())
                err.LogThreaded("::task_resume ( target_task = 0x%4.4x )", task);
        }
    }
    return err.Error();
}

rnb_err_t
RNBSocket::Write (const void *buffer, size_t length)
{
    if (m_fd == -1)
        return rnb_err;

    DNBError err;
    int bytessent = send (m_fd, buffer, length, 0);
    if (bytessent < 0)
        err.SetError(errno, DNBError::POSIX);

    if (err.Fail() || DNBLogCheckLogBit(LOG_RNB_COMM))
        err.LogThreaded("::send ( socket = %i, buffer = %p, length = %zu, flags = 0 ) => %i", m_fd, buffer, length, bytessent);

    if (bytessent < 0)
        return rnb_err;

    if (bytessent != length)
        return rnb_err;

    DNBLogThreadedIf(LOG_RNB_PACKETS, "putpkt: %*s", (int)length, (char *)buffer);   // All data is string based in debugserver, so this is safe
    DNBLogThreadedIf(LOG_RNB_COMM, "sent: %*s", (int)length, (char *)buffer);

    return rnb_success;
}

//----------------------------------------------------------------------
// MachTask::BasicInfo
//----------------------------------------------------------------------
kern_return_t
MachTask::BasicInfo(task_t task, struct task_basic_info *info)
{
    if (info == NULL)
        return KERN_INVALID_ARGUMENT;

    DNBError err;
    mach_msg_type_number_t count = TASK_BASIC_INFO_COUNT;
    err = ::task_info (task, TASK_BASIC_INFO, (task_info_t)info, &count);
    const bool log_process = DNBLogCheckLogBit(LOG_TASK);
    if (log_process || err.Fail())
        err.LogThreaded("::task_info ( target_task = 0x%4.4x, flavor = TASK_BASIC_INFO, task_info_out => %p, task_info_outCnt => %u )", task, info, count);
    if (DNBLogCheckLogBit(LOG_TASK) && DNBLogCheckLogBit(LOG_VERBOSE) && err.Success())
    {
        float user = (float)info->user_time.seconds + (float)info->user_time.microseconds / 1000000.0f;
        float system = (float)info->user_time.seconds + (float)info->user_time.microseconds / 1000000.0f;
        DNBLogThreaded ("task_basic_info = { suspend_count = %i, virtual_size = 0x%8.8llx, resident_size = 0x%8.8llx, user_time = %f, system_time = %f }",
                        info->suspend_count, 
                        (uint64_t)info->virtual_size, 
                        (uint64_t)info->resident_size, 
                        user, 
                        system);
    }
    return err.Error();
}

kern_return_t
MachTask::ShutDownExcecptionThread()
{
    DNBError err;

    err = RestoreExceptionPortInfo();

    // NULL our our exception port and let our exception thread exit
    mach_port_t exception_port = m_exception_port;
    m_exception_port = NULL;

    err.SetError(::pthread_cancel(m_exception_thread), DNBError::POSIX);
    if (DNBLogCheckLogBit(LOG_TASK) || err.Fail())
        err.LogThreaded("::pthread_cancel ( thread = %p )", m_exception_thread);

    err.SetError(::pthread_join(m_exception_thread, NULL), DNBError::POSIX);
    if (DNBLogCheckLogBit(LOG_TASK) || err.Fail())
        err.LogThreaded("::pthread_join ( thread = %p, value_ptr = NULL)", m_exception_thread);

    // Deallocate our exception port that we used to track our child process
    mach_port_t task_self = mach_task_self ();
    err = ::mach_port_deallocate (task_self, exception_port);
    if (DNBLogCheckLogBit(LOG_TASK) || err.Fail())
        err.LogThreaded("::mach_port_deallocate ( task = 0x%4.4x, name = 0x%4.4x )", task_self, exception_port);
    exception_port = NULL;

    return err.Error();
}

kern_return_t
MachException::PortInfo::Save (task_t task)
{
    count = (sizeof (ports) / sizeof (ports[0]));
    DNBLogThreadedIf(LOG_EXCEPTIONS | LOG_VERBOSE, "MachException::PortInfo::Save ( task = 0x%4.4x )", task);
    DNBError err;
    err = ::task_get_exception_ports (task, EXC_MASK_ALL, masks, &count, ports, behaviors, flavors);
    if (DNBLogCheckLogBit(LOG_EXCEPTIONS) || err.Fail())
        err.LogThreaded("::task_get_exception_ports ( task = 0x%4.4x, mask = 0x%x, maskCnt => %u, ports, behaviors, flavors )", task, EXC_MASK_ALL, count);
    if (err.Fail())
        count = 0;
    return err.Error();
}

kern_return_t
MachException::Message::Receive(mach_port_t port, mach_msg_option_t options, mach_msg_timeout_t timeout, mach_port_t notify_port)
{
    DNBError err;
    const bool log_exceptions = DNBLogCheckLogBit(LOG_EXCEPTIONS);
    mach_msg_timeout_t mach_msg_timeout = options & MACH_RCV_TIMEOUT ? timeout : 0;
    if (log_exceptions && ((options & MACH_RCV_TIMEOUT) == 0))
    {
        // Dump this log message if we have no timeout in case it never returns
        DNBLogThreaded("::mach_msg ( msg->{bits = %#x, size = %u remote_port = %#x, local_port = %#x, reserved = 0x%x, id = 0x%x}, option = %#x, send_size = %u, rcv_size = %u, rcv_name = %#x, timeout = %u, notify = %#x)",
                exc_msg.hdr.msgh_bits,
                exc_msg.hdr.msgh_size,
                exc_msg.hdr.msgh_remote_port,
                exc_msg.hdr.msgh_local_port,
                exc_msg.hdr.msgh_reserved,
                exc_msg.hdr.msgh_id,
                options,
                0,
                sizeof (exc_msg.data),
                port,
                mach_msg_timeout,
                notify_port);
    }

    err = ::mach_msg (&exc_msg.hdr,
                      options,                  // options
                      0,                        // Send size
                      sizeof (exc_msg.data),    // Receive size
                      port,                     // exception port to watch for exception on
                      mach_msg_timeout,         // timeout in msec (obeyed only if MACH_RCV_TIMEOUT is ORed into the options parameter)
                      notify_port);

    // Dump any errors we get
    if (log_exceptions)
    {
        err.LogThreaded("::mach_msg ( msg->{bits = %#x, size = %u remote_port = %#x, local_port = %#x, reserved = 0x%x, id = 0x%x}, option = %#x, send_size = %u, rcv_size = %u, rcv_name = %#x, timeout = %u, notify = %#x)",
            exc_msg.hdr.msgh_bits,
            exc_msg.hdr.msgh_size,
            exc_msg.hdr.msgh_remote_port,
            exc_msg.hdr.msgh_local_port,
            exc_msg.hdr.msgh_reserved,
            exc_msg.hdr.msgh_id,
            options,
            0,
            sizeof (exc_msg.data),
            port,
            mach_msg_timeout,
            notify_port);
    }
    return err.Error();
}

bool
MachThread::SetSuspendCountBeforeResume(bool others_stopped)
{
    DNBLogThreadedIf(LOG_THREAD | LOG_VERBOSE, "MachThread::%s ( )", __FUNCTION__);
    DNBError err;
    if (ThreadIDIsValid(m_tid) == false)
        return false;
        
    size_t times_to_resume;
        
    if (others_stopped)
    {
        if (GetBasicInfo())
        {
            times_to_resume = m_basic_info.suspend_count;
            m_suspend_count = - (times_to_resume - m_suspend_count);
        }
        else
            times_to_resume = 0;
    }
    else
    {
        times_to_resume = m_suspend_count;
        m_suspend_count = 0;
    }

    if (times_to_resume > 0)
    {
        while (times_to_resume > 0)
        {
            err = ::thread_resume (m_tid);
            if (DNBLogCheckLogBit(LOG_THREAD) || err.Fail())
                err.LogThreaded("::thread_resume (%4.4x)", m_tid);
            if (err.Success())
                --times_to_resume;
            else
            {
                if (GetBasicInfo())
                    times_to_resume = m_basic_info.suspend_count;
                else
                    times_to_resume = 0;
            }
        }
    }
    return true;
}

bool
MachThread::RestoreSuspendCount()
{
    DNBLogThreadedIf(LOG_THREAD | LOG_VERBOSE, "MachThread::%s ( )", __FUNCTION__);
    DNBError err;
    if (ThreadIDIsValid(m_tid) == false)
        return false;
    else if (m_suspendCount > m_basicInfo.suspend_count)
    {
        while (m_suspendCount > m_basicInfo.suspend_count)
        {
            err = ::thread_resume (m_tid);
            if (err.Success())
                --m_suspendCount;
            if (DNBLogCheckLogBit(LOG_THREAD) || err.Fail())
                err.LogThreaded("::thread_resume (%4.4x)", m_tid);
        }
    }
    else if (m_suspendCount < m_basicInfo.suspend_count)
    {
        while (m_suspendCount < m_basicInfo.suspend_count)
        {
            err = ::thread_suspend (m_tid);
            if (err.Success())
                --m_suspendCount;
            if (DNBLogCheckLogBit(LOG_THREAD) || err.Fail())
                err.LogThreaded("::thread_suspend (%4.4x)", m_tid);
        }
    }
    return  m_suspendCount == m_basicInfo.suspend_count;
}

bool
MachThread::RestoreSuspendCount()
{
    DNBLogThreadedIf(LOG_THREAD | LOG_VERBOSE, "MachThread::%s ( )", __FUNCTION__);
    DNBError err;
    if (ThreadIDIsValid(m_tid) == false)
        return false;
    if (m_suspendCount > 0)
    {
        while (m_suspendCount > 0)
        {
            err = ::thread_resume (m_tid);
            if (DNBLogCheckLogBit(LOG_THREAD) || err.Fail())
                err.LogThreaded("::thread_resume (%4.4x)", m_tid);
            if (err.Success())
                --m_suspendCount;
            else
            {
                if (GetBasicInfo())
                    m_suspendCount = m_basicInfo.suspend_count;
                else
                    m_suspendCount = 0;
                return false; // ??? 
            }
        }
    }
    // We don't currently really support resuming a thread that was externally
    // suspended. If/when we do, we will need to make the code below work and
    // m_suspendCount will need to become signed instead of unsigned.
//    else if (m_suspendCount < 0)
//    {
//        while (m_suspendCount < 0)
//        {
//            err = ::thread_suspend (m_tid);
//            if (err.Success())
//                ++m_suspendCount;
//            if (DNBLogCheckLogBit(LOG_THREAD) || err.Fail())
//                err.LogThreaded("::thread_suspend (%4.4x)", m_tid);
//        }
//    }
    return true;
}

rnb_err_t
RNBSocket::Read (std::string &p)
{
    char buf[1024];
    p.clear();

    // Note that BUF is on the stack so we must be careful to keep any
    // writes to BUF from overflowing or we'll have security issues.

    if (m_fd == -1)
        return rnb_err;

    //DNBLogThreadedIf(LOG_RNB_COMM, "%8u RNBSocket::%s calling read()", (uint32_t)m_timer.ElapsedMicroSeconds(true), __FUNCTION__);
    DNBError err;
    int bytesread = read (m_fd, buf, sizeof (buf));
    if (bytesread <= 0)
        err.SetError(errno, DNBError::POSIX);
    else
        p.append(buf, bytesread);

    if (err.Fail() || DNBLogCheckLogBit(LOG_RNB_COMM))
        err.LogThreaded("::read ( %i, %p, %zu ) => %i", m_fd, buf, sizeof (buf), bytesread);

    // Our port went away - we have to mark this so IsConnected will return the truth.
    if (bytesread == 0)
    {
        m_fd = -1;
        return rnb_not_connected;
    }
    else if (bytesread == -1)
    {
        m_fd = -1;
        return rnb_err;
    }
    // Strip spaces from the end of the buffer
    while (!p.empty() && isspace (p[p.size() - 1]))
        p.erase (p.size () - 1);

    // Most data in the debugserver packets valid printable characters...
    DNBLogThreadedIf(LOG_RNB_COMM, "read: %s", p.c_str());
    return rnb_success;
}

bool
MachTask::StartExceptionThread(DNBError &err)
{
    DNBLogThreadedIf(LOG_EXCEPTIONS, "MachTask::%s ( )", __FUNCTION__);
    task_t task = TaskPortForProcessID(err);
    if (MachTask::IsValid(task))
    {
        // Got the mach port for the current process
        mach_port_t task_self = mach_task_self ();

        // Allocate an exception port that we will use to track our child process
        err = ::mach_port_allocate (task_self, MACH_PORT_RIGHT_RECEIVE, &m_exception_port);
        if (err.Fail())
            return false;

        // Add the ability to send messages on the new exception port
        err = ::mach_port_insert_right (task_self, m_exception_port, m_exception_port, MACH_MSG_TYPE_MAKE_SEND);
        if (err.Fail())
            return false;

        // Save the original state of the exception ports for our child process
        SaveExceptionPortInfo();

        // We weren't able to save the info for our exception ports, we must stop...
        if (m_exc_port_info.mask == 0)
        {
            err.SetErrorString("failed to get exception port info");
            return false;
        }

        // Set the ability to get all exceptions on this port
        err = ::task_set_exception_ports (task, m_exc_port_info.mask, m_exception_port, EXCEPTION_DEFAULT | MACH_EXCEPTION_CODES, THREAD_STATE_NONE);
        if (DNBLogCheckLogBit(LOG_EXCEPTIONS) || err.Fail())
        {
            err.LogThreaded("::task_set_exception_ports ( task = 0x%4.4x, exception_mask = 0x%8.8x, new_port = 0x%4.4x, behavior = 0x%8.8x, new_flavor = 0x%8.8x )",
                            task,
                            m_exc_port_info.mask,
                            m_exception_port,
                            (EXCEPTION_DEFAULT | MACH_EXCEPTION_CODES),
                            THREAD_STATE_NONE);
        }

        if (err.Fail())
            return false;

        // Create the exception thread
        err = ::pthread_create (&m_exception_thread, NULL, MachTask::ExceptionThread, this);
        return err.Success();
    }
    else
    {
        DNBLogError("MachTask::%s (): task invalid, exception thread start failed.", __FUNCTION__);
    }
    return false;
}

nub_addr_t
MachTask::GetDYLDAllImageInfosAddress (DNBError& err)
{
    struct hack_task_dyld_info dyld_info;
    mach_msg_type_number_t count = TASK_DYLD_INFO_COUNT;
    // Make sure that COUNT isn't bigger than our hacked up struct hack_task_dyld_info.
    // If it is, then make COUNT smaller to match.
    if (count > (sizeof(struct hack_task_dyld_info) / sizeof(natural_t)))
        count = (sizeof(struct hack_task_dyld_info) / sizeof(natural_t));

    task_t task = TaskPortForProcessID (err);
    if (err.Success())
    {
        err = ::task_info (task, TASK_DYLD_INFO, (task_info_t)&dyld_info, &count);
        if (err.Success())
        {
            // We now have the address of the all image infos structure
            return dyld_info.all_image_info_addr;
        }
    }
    return INVALID_NUB_ADDRESS;
}

bool
MachTask::StartExceptionThread(DNBError &err)
{
    DNBLogThreadedIf(LOG_EXCEPTIONS, "MachTask::%s ( )", __FUNCTION__);
    task_t task = TaskPortForProcessID(err);
    if (MachTask::IsValid(task))
    {
        // Got the mach port for the current process
        mach_port_t task_self = mach_task_self ();

        // Allocate an exception port that we will use to track our child process
        err = ::mach_port_allocate (task_self, MACH_PORT_RIGHT_RECEIVE, &m_exception_port);
        if (err.Fail())
            return false;

        // Add the ability to send messages on the new exception port
        err = ::mach_port_insert_right (task_self, m_exception_port, m_exception_port, MACH_MSG_TYPE_MAKE_SEND);
        if (err.Fail())
            return false;

        // Save the original state of the exception ports for our child process
        SaveExceptionPortInfo();

        // Set the ability to get all exceptions on this port
        err = ::task_set_exception_ports (task, EXC_MASK_ALL, m_exception_port, EXCEPTION_DEFAULT | MACH_EXCEPTION_CODES, THREAD_STATE_NONE);
        if (err.Fail())
            return false;

        // Create the exception thread
        err = ::pthread_create (&m_exception_thread, NULL, MachTask::ExceptionThread, this);
        return err.Success();
    }
    else
    {
        DNBLogError("MachTask::%s (): task invalid, exception thread start failed.", __FUNCTION__);
    }
    return false;
}

rnb_err_t
RNBSocket::OpenFile (const char *path)
{
    DNBError err;
    m_fd = open (path, O_RDWR);
    if (m_fd == -1)
    {
        err.SetError(errno, DNBError::POSIX);
        err.LogThreaded ("can't open file '%s'", path);
        return rnb_not_connected;
    }
    else
    {
        struct termios stdin_termios;

        if (::tcgetattr (m_fd, &stdin_termios) == 0)
        {
            stdin_termios.c_lflag &= ~ECHO;     // Turn off echoing
            stdin_termios.c_lflag &= ~ICANON;   // Get one char at a time
            ::tcsetattr (m_fd, TCSANOW, &stdin_termios);
        }
    }
    return rnb_success;
}

kern_return_t
MachException::PortInfo::Restore (task_t task)
{
    DNBLogThreadedIf(LOG_EXCEPTIONS | LOG_VERBOSE, "MachException::PortInfo::Restore( task = 0x%4.4x )", task);
    uint32_t i = 0;
    DNBError err;
    if (count > 0)
    {
        for (i = 0; i < count; i++)
        {
            err = ::task_set_exception_ports (task, masks[i], ports[i], behaviors[i], flavors[i]);
            if (DNBLogCheckLogBit(LOG_EXCEPTIONS) || err.Fail())
            {
                err.LogThreaded("::task_set_exception_ports ( task = 0x%4.4x, exception_mask = 0x%8.8x, new_port = 0x%4.4x, behavior = 0x%8.8x, new_flavor = 0x%8.8x )", task, masks[i], ports[i], behaviors[i], flavors[i]);
                // Bail if we encounter any errors
            }

            if (err.Fail())
                break;
        }
    }
    count = 0;
    return err.Error();
}