cms_in.cc

CNC 的开放码,EMC2 V2.2.8版

    /* Read the message. */
    handle_to_global_data->offset += sizeof(CMS_HEADER);
    if (-1 ==
	handle_to_global_data->read(subdiv_data,
	    (long) header.in_buffer_size)) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Check_id so that debug variables for messages missed can be set. */
    check_id(header.write_id);

    return (status);
}

/* It takes several steps to perform a peek operation on an neutral buffer.*/
/* 1. Read the encoded  header. */
/* 2. Decode the header. */
/* 3. Check the id and size. */
/* 4. If id and size are ok, then read the message. */
CMS_STATUS CMS::peek_encoded()
{
    /* Produce error message if process does not have permission to read. */
    if (!read_permission_flag) {
	rcs_print_error("CMS: %s was not configured to read %s\n",
	    ProcessName, BufferName);
	return (status = CMS_PERMISSIONS_ERROR);
    }

    /* Check that the handle to the global memory object exists. */
    if (NULL == handle_to_global_data) {
	rcs_print_error("CMS: handle_to_global_data is NULL.\n");
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Read the encoded header for the message. */
    if (-1 == handle_to_global_data->read(encoded_header,
	    encoded_header_size)) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Decode the header and store in header structure. */
    decode_header();

    /* Determine if the message in the buffer is new to this process. */
    if (CMS_READ_OLD == check_id(header.write_id)) {
	return (CMS_READ_OLD);	/* Don't bother reading an old message. */
    }

    /* Check the size of the message. */
    if (header.in_buffer_size > max_message_size) {
	rcs_print_error
	    ("CMS:(%s) Message size of %ld exceeds maximum of %ld\n",
	    BufferName, header.in_buffer_size, max_message_size);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Read the message. */
    handle_to_global_data->offset += encoded_header_size;
    if (-1 == handle_to_global_data->read(encoded_data,
	    (long) header.in_buffer_size)) {
	rcs_print_error("CMS:(%s) Error writing to global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    return (status);
}

/* It takes several steps to perform a peek operation */
 /* when queuing is enabled on a neutral buffer. */
/* 1. Read the encoded queuing_header at the beginning of the buffer. */
/* 2. Decode the queuing_header for the buffer. */
/* 3. Get the head of the queue from the queuing_header. */
/* 4. Read the message header at the head of the queue. */
/* 5. Decode the message header. */
/* 6. Check the id and size. */
/* 7. If id and size are ok, */
 /* then read the message */
CMS_STATUS CMS::queue_peek_encoded()
{
    long queuing_header_offset;

    /* Produce error message if process does not have permission to read. */
    if (!read_permission_flag) {
	rcs_print_error("CMS: %s was not configured to read %s\n",
	    ProcessName, BufferName);
	return (status = CMS_PERMISSIONS_ERROR);
    }

    /* Check that the handle to global memory exists. */
    if (NULL == handle_to_global_data) {
	rcs_print_error("CMS: handle_to_global_data is NULL.\n");
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Store the original offset so we can update the queuing header later. */
    queuing_header_offset = handle_to_global_data->offset;

    /* Read the encoded header for the buffer. */
    if (-1 == handle_to_global_data->read(encoded_queuing_header,
	    encoded_queuing_header_size)) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Decode the queuing header and store in the queuing_header structrure. */
    decode_queuing_header();

    /* Determine if there are any unread messages. */
    if (queuing_header.queue_length == 0) {
	return (status = CMS_READ_OLD);
    }

    /* Read the header for the message. */
    handle_to_global_data->offset += queuing_header.head;
    if (-1 == handle_to_global_data->read(encoded_header,
	    encoded_header_size)) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Decode the message header and store in the header structure. */
    decode_header();

    /* Check the size of the message. */
    if (header.in_buffer_size > max_message_size) {
	rcs_print_error
	    ("CMS:(%s) Message size of %ld exceeds maximum of %ld\n",
	    BufferName, header.in_buffer_size, max_message_size);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Read the message. */
    handle_to_global_data->offset += encoded_header_size;
    if (-1 ==
	handle_to_global_data->read(encoded_data,
	    (long) header.in_buffer_size)) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Check_id so that debug variables for messages missed can be set. */
    check_id(header.write_id);

    return (status);
}

/* It takes several steps to perform a write operation. */
/* 1. Read the header. */
/* 2. Update the header. */
/* 3. Write the message. */
/* Parameters: */
 /* user_data - pointer to where the user stored the message to be written. */
CMS_STATUS CMS::write_raw(void *user_data)
{
    long current_header_in_buffer_size;

    /* Produce error message if process does not have permission to read. */
    if (!write_permission_flag) {
	rcs_print_error("CMS: %s was not configured to write to %s\n",
	    ProcessName, BufferName);
	return (status = CMS_PERMISSIONS_ERROR);
    }

    /* Store the header information to use after reading the header in the
       buffer. */
    current_header_in_buffer_size = header.in_buffer_size;

    /* Check that handle to global memory object exists. */
    if (NULL == handle_to_global_data) {
	rcs_print_error("CMS: handle_to_global_data is NULL.\n");
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }
#if 0
    /* Check that buffer is large enough for this message. */
    if (header.in_buffer_size > max_message_size) {
	rcs_print_error
	    ("CMS:(%s) Message size %ld exceeds maximum for this buffer of %ld.\n",
	    BufferName, header.in_buffer_size, max_message_size);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }
#endif

    /* Read the header. */
    if (-1 == handle_to_global_data->read(&header, sizeof(header))) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Update the header. */
    header.was_read = 0;
    header.write_id++;
    if (split_buffer) {
	if ((header.write_id & 1) != toggle_bit) {
	    header.write_id++;
	}
    }
    header.in_buffer_size = current_header_in_buffer_size;
    if (-1 == handle_to_global_data->write(&header, sizeof(header))) {
	rcs_print_error("CMS:(%s) Error writing to global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Write the message. */
    if (!disable_final_write_raw_for_dma) {
	handle_to_global_data->offset += sizeof(CMS_HEADER);
	if (-1 == handle_to_global_data->write(user_data, (long)
		current_header_in_buffer_size)) {
	    rcs_print_error
		("CMS:(%s) Error writing %ld bytes to global memory at offset %X\n (See  %s line %d.)\n",
		BufferName, header.in_buffer_size, user_data, __FILE__,
		__LINE__);
	    return (status = CMS_INTERNAL_ACCESS_ERROR);
	}
    }

    return (status = CMS_WRITE_OK);
}

/* It takes several steps to perform a write operation when queuing is enabled. */
/* 1. Read the qeuing header at the begining of the buffer. */
/* 2. Determine the amount of free space and where the next node can be placed.*/
/* 3. Set up message header from info in the queuing header. */
/* 4. Write the message header and message  at the tail of the queue. */
/* 5. Update the queuing header. */
/* Parameters: */
 /* user_data - pointer to where the user stored the message to be written. */
CMS_STATUS CMS::queue_write_raw(void *user_data)
{
    CMS_HEADER current_header;
    long queuing_header_offset;
    long original_tail;

    /* Produce error message if process does not have permission to read. */
    if (!write_permission_flag) {
	rcs_print_error("CMS: %s was not configured to write to %s\n",
	    ProcessName, BufferName);
	return (status = CMS_PERMISSIONS_ERROR);
    }

    /* Store the header information to use after reading the header in the
       buffer. */
    current_header = header;

    /* Check that the handle to the global memory object exists. */
    if (NULL == handle_to_global_data) {
	rcs_print_error("CMS: handle_to_global_data is NULL.\n");
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Store the original offset so we can update the queuing header later. */
    queuing_header_offset = handle_to_global_data->offset;

    /* Read the queuing header at the beginning of the buffer. */
    if (-1 == handle_to_global_data->read(&queuing_header,
	    sizeof(CMS_QUEUING_HEADER))) {
	rcs_print_error
	    ("CMS:(%s) Error reading from global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Determine amount of free space and location of next node. */

    if (handle_to_global_data->size - queuing_header.tail -
	queuing_header_offset >
	((long) (header.in_buffer_size + sizeof(CMS_HEADER)))
	&& queuing_header.tail > queuing_header.head) {
	free_space =
	    handle_to_global_data->size - queuing_header.tail -
	    queuing_header_offset;
    } else if (queuing_header.tail < queuing_header.head) {
	free_space = queuing_header.head - queuing_header.tail;
    } else if (queuing_header.head >
	((long) (queuing_header_offset + sizeof(CMS_QUEUING_HEADER) +
		(header.in_buffer_size + sizeof(CMS_HEADER))))) {
	queuing_header.end_queue_space = queuing_header.tail;
	queuing_header.tail = sizeof(CMS_QUEUING_HEADER);
	free_space =
	    queuing_header.head - sizeof(CMS_QUEUING_HEADER) -
	    queuing_header_offset;
    } else {
	free_space = 0;
    }

    if (queuing_header.queue_length == 0) {
	queuing_header.head = queuing_header.tail =
	    sizeof(CMS_QUEUING_HEADER);
	queuing_header.queue_length = 0;
	queuing_header.end_queue_space = queuing_header.tail;
	free_space = handle_to_global_data->size
	    - sizeof(CMS_QUEUING_HEADER) - queuing_header_offset;
    }

    if (cms_print_queue_free_space) {
	rcs_print("queue free space = %d\n", free_space);
	rcs_print(" { head=%d,tail=%d,end=%d,length=%d,id=%d }\n",
	    queuing_header.head,
	    queuing_header.tail,
	    queuing_header.end_queue_space,
	    queuing_header.queue_length, queuing_header.write_id);
    }

    /* Check to see if there is enough free space. */
    if (free_space < ((long) (header.in_buffer_size + sizeof(CMS_HEADER)))) {
	if (cms_print_queue_free_space || cms_print_queue_full_messages) {
	    rcs_print_error("CMS: %s message queue is full.\n", BufferName);
	    rcs_print_error
		("(continued) CMS: Message requires %ld bytes but only %ld bytes are left.\n",
		header.in_buffer_size, free_space);
	}
	return (status = CMS_QUEUE_FULL);
    }

    /* Store original tail so we'll know where to store the message. */
    original_tail = queuing_header.tail;

    /* Update the queuing header. */
    queuing_header.tail += header.in_buffer_size + sizeof(CMS_HEADER);
    queuing_header.queue_length++;
    queuing_header.write_id++;
    if (queuing_header.end_queue_space < queuing_header.tail) {
	queuing_header.end_queue_space = queuing_header.tail;
    }
    if (-1 == handle_to_global_data->write(&queuing_header,
	    sizeof(CMS_QUEUING_HEADER))) {
	rcs_print_error("CMS:(%s) Error writing to global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Setup message header. */
    header.write_id = queuing_header.write_id;
    header.was_read = 0;
    header.in_buffer_size = current_header.in_buffer_size;

    /* Write the message header. */
    handle_to_global_data->offset += original_tail;
    if (-1 == handle_to_global_data->write(&header, sizeof(header))) {
	rcs_print_error("CMS:(%s) Error writing to global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    /* Write the message. */
    handle_to_global_data->offset += sizeof(CMS_HEADER);
    if (-1 == handle_to_global_data->write(user_data,
	    (long) header.in_buffer_size)) {
	rcs_print_error("CMS:(%s) Error writing to global memory at %s:%d\n",
	    BufferName, __FILE__, __LINE__);
	return (status = CMS_INTERNAL_ACCESS_ERROR);
    }

    return (status = CMS_WRITE_OK);
}

/* It takes several steps to perform a write operation on a neutral buffer. */
/* 1. Read the header. */
/* 2. Update the header. */
/* 3. Write the message. */
CMS_STATUS CMS::write_encoded()
{
    CMS_HEADER current_header;

    /* Produce error message if process does not have permission to read. */
    if (!write_permission_flag) {
	rcs_print_error("CMS: %s was not configured to write to %s\n",
	    ProcessName, BufferName);
	return (status = CMS_PERMISSIONS_ERROR);
    }