3 * Copyright 2005 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
7 * GNU Radio is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2, or (at your option)
12 * GNU Radio is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
20 * Boston, MA 02110-1301, USA.
27 #include <gr_message_source.h>
28 #include <gr_io_signature.h>
31 #include <sys/types.h>
37 // public constructor that returns a shared_ptr
39 gr_message_source_sptr
40 gr_make_message_source(size_t itemsize, int msgq_limit)
42 return gr_message_source_sptr(new gr_message_source(itemsize, msgq_limit));
45 gr_message_source::gr_message_source (size_t itemsize, int msgq_limit)
46 : gr_sync_block("message_source",
47 gr_make_io_signature(0, 0, 0),
48 gr_make_io_signature(1, 1, itemsize)),
49 d_itemsize(itemsize), d_msgq(gr_make_msg_queue(msgq_limit)), d_msg_offset(0), d_eof(false)
53 gr_message_source::~gr_message_source()
58 gr_message_source::work(int noutput_items,
59 gr_vector_const_void_star &input_items,
60 gr_vector_void_star &output_items)
62 char *out = (char *) output_items[0];
65 while (nn < noutput_items){
68 // Consume whatever we can from the current message
70 int mm = std::min(noutput_items - nn, (int)((d_msg->length() - d_msg_offset) / d_itemsize));
71 memcpy (out, &(d_msg->msg()[d_msg_offset]), mm * d_itemsize);
74 out += mm * d_itemsize;
75 d_msg_offset += mm * d_itemsize;
76 assert(d_msg_offset <= d_msg->length());
78 if (d_msg_offset == d_msg->length()){
79 if (d_msg->type() == 1) // type == 1 sets EOF
88 if (d_msgq->empty_p() && nn > 0){ // no more messages in the queue, return what we've got
95 d_msg = d_msgq->delete_head(); // block, waiting for a message
98 if ((d_msg->length() % d_itemsize) != 0)
99 throw std::runtime_error("msg length is not a multiple of d_itemsize");