added midi captureing code

1 files changed, 93 insertions, 0 deletions

diff --git a/apps/midi.c b/apps/midi.c
new file mode 100644
index 0000000..45cb12f
--- /dev/null
+++ b/apps/midi.c
@@ -0,0 +1,93 @@
+/*
+ *  dolmetschctl
+ *
+ *
+ *  Copyright (C) 2015 Christian Pointner <equinox@spreadspace.org>
+ *
+ *  This file is part of dolmetschctl.
+ *
+ *  dolmetschctl is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  any later version.
+ *
+ *  dolmetschctl is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with dolmetschctl. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <error.h>
+#include <poll.h>
+
+#include "midi.h"
+
+
+int midi_init(midi_t* m, const char* device)
+{
+  if(!m)
+    return -1;
+
+  int ret = snd_rawmidi_open(&(m->input_), &(m->output_), device, SND_RAWMIDI_NONBLOCK);
+  if(ret < 0) {
+    error(0, 0, "cannot open midi port '%s': %s", device, snd_strerror(ret));
+    return ret;
+  }
+
+  return 0;
+}
+
+void midi_run(midi_t* m)
+{
+  if(!m)
+    return;
+
+  int npfds;
+  struct pollfd *pfds;
+
+  npfds = snd_rawmidi_poll_descriptors_count(m->input_);
+  pfds = alloca(npfds * sizeof(struct pollfd));
+  snd_rawmidi_poll_descriptors(m->input_, pfds, npfds);
+  for (;;) {
+    int err = poll(pfds, npfds, 200);
+    if(err < 0 && errno == EINTR)
+      break;
+    if(err < 0) {
+      error(0, errno, "poll failed");
+      break;
+    }
+    /* if(err == 0) { */
+    /*       // TIMEOUT */
+    /* } */
+
+    unsigned short revents;
+    if((err = snd_rawmidi_poll_descriptors_revents(m->input_, pfds, npfds, &revents)) < 0) {
+      error(0, 0, "cannot get poll events: %s", snd_strerror(errno));
+      break;
+    }
+    if(revents & (POLLERR | POLLHUP))
+      break;
+    if(!(revents & POLLIN))
+      continue;
+
+    u_int8_t buf[256];
+    int ret = snd_rawmidi_read(m->input_, buf, sizeof(buf));
+    if (ret == -EAGAIN)
+      continue;
+    if(ret < 0) {
+      error(0, 0, "cannot read from midi port: %s", snd_strerror(ret));
+      break;
+    }
+
+    int i;
+    for (i = 0; i < ret; ++i)
+      printf("%02X%c", buf[i], (i >= (ret-1)) ? '\n' : ' ');
+  }
+
+}