module Orocos::MQueue

# File lib/orocos/mqueue.rb, line 55
def auto=(value)
    if value
        raise ArgumentError, "cannot turn automatic MQ handling. It is either not built into the RTT, or you don't have enough permissions to create message queues (in which case a warning message has been displayed)"
    end
end

# File lib/orocos/mqueue.rb, line 54
def auto?; false end

# File lib/orocos/mqueue.rb, line 14
def self.available?
    if @available.nil?
        @available=
            if !defined?(RTT_TRANSPORT_MQ_ID)
                false
            elsif error = MQueue.try_mq_open
                Orocos.warn "the RTT is built with MQ support, but creating message queues fails with: #{error}"
                false
            elsif TRANSPORT_MQ != RTT_TRANSPORT_MQ_ID
                raise InternalError, "hardcoded value of TRANSPORT_MQ differs from the transport ID from RTT (#{TRANSPORT_MQ} != #{RTT_TRANSPORT_MQ_ID}. Set the value at the top of #{File.expand_path(__FILE__)} to #{RTT_TRANSPORT_MQ_ID} and report to the orocos.rb developers"
            else
                true
            end
    else
        @available
    end
end

# File lib/orocos/mqueue.rb, line 158
def self.msg_max
    if !@msg_max.nil?
        return @msg_max
    end

    if !File.readable?('/proc/sys/fs/mqueue/msg_max')
        @msg_max = false
    else
        @msg_max = Integer(File.read('/proc/sys/fs/mqueue/msg_max').chomp)
    end
end

# File lib/orocos/mqueue.rb, line 171
def self.msgsize_max
    if !@msgsize_max.nil?
        return @msgsize_max
    end

    if !File.readable?('/proc/sys/fs/mqueue/msgsize_max')
        @msgsize_max = false
    else
        @msgsize_max = Integer(File.read('/proc/sys/fs/mqueue/msgsize_max').chomp)
    end
end

static VALUE mqueue_transportable_type_names(VALUE mod)
{
    RTT::types::TypeInfoRepository::shared_ptr rtt_types =
        RTT::types::TypeInfoRepository::Instance();

    VALUE result = rb_ary_new();
    vector<string> all_types = rtt_types->getTypes();
    for (vector<string>::iterator it = all_types.begin(); it != all_types.end(); ++it)
    {
        RTT::types::TypeInfo* ti = rtt_types->type(*it);
        vector<int> transports = ti->getTransportNames();
        if (find(transports.begin(), transports.end(), ORO_MQUEUE_PROTOCOL_ID) != transports.end())
            rb_ary_push(result, rb_str_new2(it->c_str()));
    }
    return result;
}

static VALUE try_mq_open(VALUE mod)
{
    int this_pid = getpid();
    std::string queue_name = std::string("/orocosrb_") + boost::lexical_cast<std::string>(this_pid);

    mq_attr attributes;
    attributes.mq_flags = 0;
    attributes.mq_maxmsg = 1;
    attributes.mq_msgsize = 1;
    mqd_t setup = mq_open(queue_name.c_str(), O_RDWR | O_CREAT, S_IREAD | S_IWRITE, &attributes);
    if (setup == -1)
        return rb_str_new2(strerror(errno));
    else
    {
        mq_close(setup);
        mq_unlink(queue_name.c_str());
        return Qnil;
    }
}

# File lib/orocos/mqueue.rb, line 137
def self.valid_sizes?(buffer_size, data_size)
    if !msg_max || !msgsize_max
        Orocos.warn "the system-level MQ limits msg_max and msgsize_max parameters are unknown on this OS. I am disabling MQ support"
        return false
    end

    if buffer_size > msg_max
        msg = yield if block_given?
        Orocos.warn "#{msg}: required buffer size #{buffer_size} is greater than the maximum that the system allows (#{msg_max}). On linux systems, you can use /proc/sys/fs/mqueue/msg_max to change this limit"
        return false
    end

    if data_size > msgsize_max
        msg = yield if block_given?
        Orocos.warn "#{msg}: required sample size #{data_size} is greater than the maximum that the system allows (#{msgsize_max}). On linux systems, you can use /proc/sys/fs/mqueue/msgsize_max to change this limit"
        return false
    end
    return true
end

# File lib/orocos/mqueue.rb, line 124
attr_predicate :auto_fallback_to_corba?, true

# File lib/orocos/mqueue.rb, line 89
attr_predicate :auto_sizes?, true

# File lib/orocos/mqueue.rb, line 106
attr_predicate :validate_sizes?, true

# File lib/orocos/mqueue.rb, line 73
attr_predicate :warn?, true