X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/4c672170094ffb7a1ef6e1afeb23f55f3da417d7..4dadf1a26a3a9b619f7d91cbc435c7d9429d64d3:/lib/alsabg.h

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+/*
+ * This file is part of DisOrder.
+ * Copyright (C) 2008 Richard Kettlewell
+ *
+ * This program 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ */
+/** @file alsabg.h
+ * @brief Background-thread interface to ALSA
+ *
+ * This wraps ALSA with an interface which calls back to the client from a
+ * thread.  It's not intended for completely general use, just what DisOrder
+ * needs.
+ */
+
+#ifndef ALSABG_H
+#define ALSABG_H
+
+/** @brief Supply audio callback
+ * @param dst Where to write audio data
+ * @param nsamples Number of samples to write
+ *
+ * This function should write up to @p *nsamples samples of data at
+ * @p dst, and return the number of samples written, or -1 if some error
+ * occurred.  It will be called in a background thread.
+ */
+typedef int alsa_bg_supply(void *dst,
+			   unsigned nsamples);
+
+void alsa_bg_init(const char *device,
+		  alsa_bg_supply *supply);
+
+void alsa_bg_enable(void);
+
+void alsa_bg_disable(void);
+
+void alsa_bg_close(void);
+
+#endif /* ALSABG_H */
+
+/*
+Local Variables:
+c-basic-offset:2
+comment-column:40
+fill-column:79
+indent-tabs-mode:nil
+End:
+*/