libs/ardour/midi_ring_buffer.cc

   1 /*
   2     Copyright (C) 2006-2008 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17 */
  18
  19 #include "pbd/compose.h"
  20
  21 #include "ardour/debug.h"
  22 #include "ardour/midi_ring_buffer.h"
  23 #include "ardour/midi_buffer.h"
  24 #include "ardour/event_type_map.h"
  25
  26 using namespace std;
  27 using namespace ARDOUR;
  28 using namespace PBD;
  29
  30 /** Read a block of MIDI events from buffer into a MidiBuffer.
  31  *
  32  * Timestamps of events returned are relative to start (i.e. event with stamp 0
  33  * occurred at start), with offset added.
  34  */
  35 template<typename T>
  36 size_t
  37 MidiRingBuffer<T>::read(MidiBuffer& dst, nframes_t start, nframes_t end, nframes_t offset)
  38 {
  39         if (this->read_space() == 0) {
  40                 return 0;
  41         }
  42
  43         T                 ev_time;
  44         Evoral::EventType ev_type;
  45         uint32_t          ev_size;
  46
  47         size_t count = 0;
  48
  49         while (this->read_space() >= sizeof(T) + sizeof(Evoral::EventType) + sizeof(uint32_t)) {
  50
  51                 this->full_peek(sizeof(T), (uint8_t*)&ev_time);
  52
  53                 if (ev_time > end) {
  54                         DEBUG_TRACE (DEBUG::MidiDiskstreamIO, string_compose ("MRB event @ %1 past end @ %2\n", ev_time, end));
  55                         break;
  56                 } else if (ev_time < start) {
  57                         DEBUG_TRACE (DEBUG::MidiDiskstreamIO, string_compose ("MRB event @ %1 before start @ %2\n", ev_time, start));
  58                         break;
  59                 } else {
  60                         DEBUG_TRACE (DEBUG::MidiDiskstreamIO, string_compose ("MRB event @ %1 in range %2 .. %3\n", ev_time, start, end));
  61                 }
  62
  63                 bool success = read_prefix(&ev_time, &ev_type, &ev_size);
  64                 if (!success) {
  65                         cerr << "WARNING: error reading event prefix from MIDI ring" << endl;
  66                         continue;
  67                 }
  68
  69                 // This event marks a loop end (i.e. the next event's timestamp will be non-monotonic)
  70                 if (ev_type == LoopEventType) {
  71                         /*ev_time -= start;
  72                           ev_time += offset;*/
  73                         // cerr << "MRB loop boundary @ " << ev_time << endl;
  74
  75                         // Return without reading data or writing to buffer (loop events have no data)
  76                         // FIXME: This is not correct, loses events after the loop this cycle
  77                         return count + 1;
  78                 }
  79
  80                 uint8_t status;
  81                 success = this->full_peek(sizeof(uint8_t), &status);
  82                 assert(success); // If this failed, buffer is corrupt, all hope is lost
  83
  84                 // Ignore event if it doesn't match channel filter
  85                 if (is_channel_event(status) && get_channel_mode() == FilterChannels) {
  86                         const uint8_t channel = status & 0x0F;
  87                         if (!(get_channel_mask() & (1L << channel))) {
  88                                 // cerr << "MRB skipping event due to channel mask" << endl;
  89                                 this->skip(ev_size); // Advance read pointer to next event
  90                                 continue;
  91                         }
  92                 }
  93
  94                 assert(ev_time >= start);
  95                 ev_time -= start;
  96                 ev_time += offset;
  97
  98                 // write the timestamp to address (write_loc - 1)
  99                 uint8_t* write_loc = dst.reserve(ev_time, ev_size);
 100                 if (write_loc == NULL) {
 101                         // cerr << "MRB: Unable to reserve space in buffer, event skipped";
 102                         this->skip (ev_size); // Advance read pointer to next event
 103                         continue;
 104                 }
 105
 106                 // write MIDI buffer contents
 107                 success = read_contents (ev_size, write_loc);
 108
 109 #ifndef NDEBUG
 110                 DEBUG_TRACE (DEBUG::MidiDiskstreamIO, "wrote MidiEvent to Buffer: ");
 111                 for (size_t i=0; i < ev_size; ++i) {
 112                         DEBUG_STR_DECL(a);
 113                         DEBUG_STR_APPEND(a,hex);
 114                         DEBUG_STR_APPEND(a,"0x");
 115                         DEBUG_STR_APPEND(a,(int)write_loc[i]);
 116                         DEBUG_TRACE (DEBUG::MidiDiskstreamIO, DEBUG_STR(a).str());
 117                 }
 118                 DEBUG_TRACE (DEBUG::MidiDiskstreamIO, "\n");
 119 #endif
 120
 121                 if (success) {
 122                         if (is_channel_event(status) && get_channel_mode() == ForceChannel) {
 123                                 write_loc[0] = (write_loc[0] & 0xF0) | (get_channel_mask() & 0x0F);
 124                         }
 125                         ++count;
 126                 } else {
 127                         cerr << "WARNING: error reading event contents from MIDI ring" << endl;
 128                 }
 129         }
 130
 131         return count;
 132 }
 133 template<typename T>
 134 void
 135 MidiRingBuffer<T>::dump(ostream& str)
 136 {
 137         size_t rspace;
 138
 139         if ((rspace = this->read_space()) == 0) {
 140                 str << "MRB::dump: empty\n";
 141                 return;
 142         }
 143
 144         T                 ev_time;
 145         Evoral::EventType ev_type;
 146         uint32_t          ev_size;
 147         size_t read_ptr = g_atomic_int_get (&this->_read_ptr);
 148
 149         str << "Dump @ " << read_ptr << endl;
 150
 151         while (1) {
 152                 uint8_t* wp;
 153                 uint8_t* data;
 154                 size_t write_ptr;
 155
 156 #define space(r,w) ((w > r) ? (w - r) : ((w - r + this->_size) % this->_size))
 157
 158                 write_ptr  = g_atomic_int_get (&this->_write_ptr);
 159                 if (space (read_ptr, write_ptr) < sizeof (T)) {
 160                         break;
 161                 }
 162
 163                 wp = &this->_buf[read_ptr];
 164                 memcpy (&ev_time, wp, sizeof (T));
 165                 read_ptr = (read_ptr + sizeof (T)) % this->_size;
 166                 str << "time " << ev_time;
 167
 168                 write_ptr  = g_atomic_int_get (&this->_write_ptr);
 169                 if (space (read_ptr, write_ptr) < sizeof (ev_type)) {
 170                         break;
 171                 }
 172
 173                 wp = &this->_buf[read_ptr];
 174                 memcpy (&ev_type, wp, sizeof (ev_type));
 175                 read_ptr = (read_ptr + sizeof (ev_type)) % this->_size;
 176                 str << " type " << ev_type;
 177
 178                 write_ptr  = g_atomic_int_get (&this->_write_ptr);
 179                 if (space (read_ptr, write_ptr) < sizeof (ev_size)) {
 180                         str << "!OUT!\n";
 181                         break;
 182                 }
 183
 184                 wp = &this->_buf[read_ptr];
 185                 memcpy (&ev_size, wp, sizeof (ev_size));
 186                 read_ptr = (read_ptr + sizeof (ev_size)) % this->_size;
 187                 str << " size " << ev_size;
 188
 189                 write_ptr  = g_atomic_int_get (&this->_write_ptr);
 190                 if (space (read_ptr, write_ptr) < ev_size) {
 191                         str << "!OUT!\n";
 192                         break;
 193                 }
 194
 195                 data = new uint8_t[ev_size];
 196
 197                 wp = &this->_buf[read_ptr];
 198                 memcpy (data, wp, ev_size);
 199                 read_ptr = (read_ptr + ev_size) % this->_size;
 200
 201                 for (uint32_t i = 0; i != ev_size; ++i) {
 202                         str << ' ' << hex << (int) data[i] << dec;
 203                 }
 204
 205                 str << endl;
 206
 207                 delete [] data;
 208         }
 209 }
 210
 211
 212 template class MidiRingBuffer<nframes_t>;
 213