1 /* -*- c++ -*- */
2 /*
3 * Copyright 2012 Free Software Foundation, Inc.
4 *
5 * This file is part of GNU Radio
6 *
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 3, or (at your option)
10 * any later version.
11 *
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.
16 *
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.
21 */
22
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26
27 #include "repack_bits_bb_impl.h"
28 #include <gnuradio/io_signature.h>
29
30 namespace gr {
31 namespace blocks {
32
make(int k,int l,const std::string & len_tag_key,bool align_output,endianness_t endianness)33 repack_bits_bb::sptr repack_bits_bb::make(int k,
34 int l,
35 const std::string& len_tag_key,
36 bool align_output,
37 endianness_t endianness)
38 {
39 return gnuradio::get_initial_sptr(
40 new repack_bits_bb_impl(k, l, len_tag_key, align_output, endianness));
41 }
42
repack_bits_bb_impl(int k,int l,const std::string & len_tag_key,bool align_output,endianness_t endianness)43 repack_bits_bb_impl::repack_bits_bb_impl(int k,
44 int l,
45 const std::string& len_tag_key,
46 bool align_output,
47 endianness_t endianness)
48 : tagged_stream_block("repack_bits_bb",
49 io_signature::make(1, 1, sizeof(char)),
50 io_signature::make(1, 1, sizeof(char)),
51 len_tag_key),
52 d_k(k),
53 d_l(l),
54 d_packet_mode(!len_tag_key.empty()),
55 d_in_index(0),
56 d_out_index(0),
57 d_align_output(align_output),
58 d_endianness(endianness)
59 {
60 if (d_k > 8 || d_k < 1 || d_l > 8 || d_l < 1) {
61 throw std::invalid_argument("k and l must be in [1, 8]");
62 }
63
64 set_relative_rate((uint64_t)d_k, (uint64_t)d_l);
65 }
66
set_k_and_l(int k,int l)67 void repack_bits_bb_impl::set_k_and_l(int k, int l)
68 {
69 gr::thread::scoped_lock guard(d_setlock);
70 d_k = k;
71 d_l = l;
72 set_relative_rate((uint64_t)d_k, (uint64_t)d_l);
73 }
74
~repack_bits_bb_impl()75 repack_bits_bb_impl::~repack_bits_bb_impl() {}
76
calculate_output_stream_length(const gr_vector_int & ninput_items)77 int repack_bits_bb_impl::calculate_output_stream_length(const gr_vector_int& ninput_items)
78 {
79 int n_out_bytes_required = (ninput_items[0] * d_k) / d_l;
80 if ((ninput_items[0] * d_k) % d_l &&
81 (!d_packet_mode || (d_packet_mode && !d_align_output))) {
82 n_out_bytes_required++;
83 }
84
85 return n_out_bytes_required;
86 }
87
work(int noutput_items,gr_vector_int & ninput_items,gr_vector_const_void_star & input_items,gr_vector_void_star & output_items)88 int repack_bits_bb_impl::work(int noutput_items,
89 gr_vector_int& ninput_items,
90 gr_vector_const_void_star& input_items,
91 gr_vector_void_star& output_items)
92 {
93 gr::thread::scoped_lock guard(d_setlock);
94 const unsigned char* in = (const unsigned char*)input_items[0];
95 unsigned char* out = (unsigned char*)output_items[0];
96 int bytes_to_write = noutput_items;
97
98 if (d_packet_mode) { // noutput_items could be larger than necessary
99 int bytes_to_read = ninput_items[0];
100 bytes_to_write = bytes_to_read * d_k / d_l;
101 if (!d_align_output && (((bytes_to_read * d_k) % d_l) != 0)) {
102 bytes_to_write++;
103 }
104 }
105
106 int n_read = 0;
107 int n_written = 0;
108 switch (d_endianness) {
109 case GR_LSB_FIRST:
110 while (n_written < bytes_to_write && n_read < ninput_items[0]) {
111 if (d_out_index == 0) { // Starting a fresh byte
112 out[n_written] = 0;
113 }
114 out[n_written] |= ((in[n_read] >> d_in_index) & 0x01) << d_out_index;
115
116 d_in_index = (d_in_index + 1) % d_k;
117 d_out_index = (d_out_index + 1) % d_l;
118 if (d_in_index == 0) {
119 n_read++;
120 d_in_index = 0;
121 }
122 if (d_out_index == 0) {
123 n_written++;
124 d_out_index = 0;
125 }
126 }
127
128 if (d_packet_mode) {
129 if (d_out_index) {
130 n_written++;
131 d_out_index = 0;
132 }
133 } else {
134 consume_each(n_read);
135 }
136 break;
137
138
139 case GR_MSB_FIRST:
140 while (n_written < bytes_to_write && n_read < ninput_items[0]) {
141 if (d_out_index == 0) { // Starting a fresh byte
142 out[n_written] = 0;
143 }
144 out[n_written] |= ((in[n_read] >> (d_k - 1 - d_in_index)) & 0x01)
145 << (d_l - 1 - d_out_index);
146
147 d_in_index = (d_in_index + 1) % d_k;
148 d_out_index = (d_out_index + 1) % d_l;
149 if (d_in_index == 0) {
150 n_read++;
151 d_in_index = 0;
152 }
153 if (d_out_index == 0) {
154 n_written++;
155 d_out_index = 0;
156 }
157 }
158
159 if (d_packet_mode) {
160 if (d_out_index) {
161 n_written++;
162 d_out_index = 0;
163 }
164 } else {
165 consume_each(n_read);
166 }
167 break;
168
169 default:
170 throw std::runtime_error("repack_bits_bb: unrecognized endianness value.");
171 }
172
173 return n_written;
174 }
175
176 } /* namespace blocks */
177 } /* namespace gr */
178