Initial revision

src/mixer/Makefile

@@ -0,0 +1,41 @@
+#
+# Makefile for ALSA library
+# Copyright (c) 1994-98 by Jaroslav Kysela <perex@jcu.cz>
+#
+
+include ../../Makefile.conf
+
+TARGET=libmixer.a
+STARGET=libmixer.Sa
+OBJECTS=mixer.o
+SOBJECTS=mixer.So
+TARGETS=$(TARGET) $(STARGET)
+
+.SUFFIXES:
+.SUFFIXES: .c .s .S .o .So .a .Sa
+
+.c.o:
+	$(CC) $(COPTS) $(INCLUDE) -c -o $*.o $<
+.c.So:
+	$(CC) $(COPTS) $(INCLUDE) -fPIC -c -o $*.So $<
+
+all: $(TARGETS)	
+
+$(TARGET): .depend $(OBJECTS)
+	$(LINKER) -r -o $@ $(OBJECTS)
+
+$(STARGET): .depend $(SOBJECTS)
+	$(LINKER) -r -o $@ $(SOBJECTS)
+
+clean:
+	rm -f core .depend *.o *.So *.a *.Sa *.orig *~
+
+.depend:
+	$(CPP) $(COPTS) $(INCLUDE) -M *.c > .depend
+
+#
+# include a dependency file if one exists
+#
+ifeq (.depend,$(wildcard .depend))
+include .depend
+endif

src/mixer/mixer.c

@@ -0,0 +1,224 @@
+/*
+ *  Mixer Interface - main file
+ *  Copyright (c) 1998 by Jaroslav Kysela <perex@jcu.cz>
+ *
+ *
+ *   This library is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Library 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 Library General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Library General Public
+ *   License along with this library; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include "soundlib.h"
+
+#define SND_FILE_MIXER		"/dev/sndmixer%i%i"
+#define SND_CTL_VERSION_MAX	SND_PROTOCOL_VERSION( 1, 0, 0 )
+ 
+typedef struct {
+  int card;
+  int device;
+  int fd;
+} snd_mixer_t;
+ 
+int snd_mixer_open( void **handle, int card, int device )
+{
+  int fd, ver;
+  char filename[32];
+  snd_mixer_t *mixer;
+
+  *handle = NULL;
+  if ( card < 0 || card >= SND_CARDS ) return -EINVAL;
+  sprintf( filename, SND_FILE_MIXER, card, device );
+  if ( (fd = open( filename, O_RDWR )) < 0 ) return -errno;
+  if ( ioctl( fd, SND_MIXER_IOCTL_PVERSION, &ver ) < 0 ) {
+    close( fd );
+    return -errno;
+  }
+  if ( ver > SND_CTL_VERSION_MAX ) return -SND_ERROR_UNCOMPATIBLE_VERSION;
+  mixer = (snd_mixer_t *)calloc( 1, sizeof( snd_mixer_t ) );
+  if ( mixer == NULL ) {
+    close( fd );
+    return -ENOMEM;
+  }
+  mixer -> card = card;
+  mixer -> device = device;
+  mixer -> fd = fd;
+  *handle = mixer;
+  return 0;
+}
+
+int snd_mixer_close( void *handle )
+{
+  snd_mixer_t *mixer;
+  int res;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  res = close( mixer -> fd ) < 0 ? -errno : 0;
+  free( mixer );
+  return res;
+}
+
+int snd_mixer_file_descriptor( void *handle )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  return mixer -> fd;
+}
+
+int snd_mixer_channels( void *handle )
+{
+  snd_mixer_t *mixer;
+  int result;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_CHANNELS, &result ) < 0 )
+    return -errno;
+  return result;
+}
+
+int snd_mixer_info( void *handle, snd_mixer_info_t *info )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_INFO, info ) < 0 )
+    return -errno;
+  return 0;
+}
+
+int snd_mixer_exact_mode( void *handle, int enable )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_EXACT, &enable ) < 0 )
+    return -errno;
+  return 0;  
+}
+
+int snd_mixer_channel( void *handle, const char *channel_id )
+{
+  snd_mixer_t *mixer;
+  snd_mixer_channel_info_t info;
+  int idx, channels, err;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  /* bellow implementation isn't optimized for speed */
+  /* info about channels should be cached in the snd_mixer_t structure */
+  if ( (channels = snd_mixer_channels( handle )) < 0 )
+    return channels;
+  for ( idx = 0; idx < channels; idx++ ) {
+    if ( (err = snd_mixer_channel_info( handle, idx, &info )) < 0 )
+      return err;
+    if ( !strncmp( channel_id, info.name, sizeof( info.name ) ) )
+      return idx;
+  }
+  return -EINVAL;
+}
+
+int snd_mixer_channel_info( void *handle, int channel, snd_mixer_channel_info_t *info )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  info -> channel = channel;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_CHANNEL_INFO, info ) < 0 )
+    return -errno;
+  return 0;
+}
+
+int snd_mixer_channel_read( void *handle, int channel, snd_mixer_channel_t *data )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  data -> channel = channel;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_CHANNEL_READ, data ) < 0 )
+    return -errno;
+  return 0;
+}
+
+int snd_mixer_channel_write( void *handle, int channel, snd_mixer_channel_t *data )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  data -> channel = channel;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_CHANNEL_WRITE, data ) < 0 )
+    return -errno;
+  return 0;
+}
+
+int snd_mixer_special_read( void *handle, snd_mixer_special_t *special )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_SPECIAL_READ, special ) < 0 )
+    return -errno;
+  return 0;
+}
+
+int snd_mixer_special_write( void *handle, snd_mixer_special_t *special )
+{
+  snd_mixer_t *mixer;
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  if ( ioctl( mixer -> fd, SND_MIXER_IOCTL_SPECIAL_WRITE, special ) < 0 )
+    return -errno;
+  return 0;
+}
+
+int snd_mixer_read( void *handle, snd_mixer_callbacks_t *callbacks )
+{
+  snd_mixer_t *mixer;
+  int idx, result, count;
+  unsigned int cmd, tmp;
+  unsigned char buffer[ 64 ];
+  
+  mixer = (snd_mixer_t *)handle;
+  if ( !mixer ) return -EINVAL;
+  count = 0;
+  while ( (result = read( mixer -> fd, &buffer, sizeof( buffer ))) > 0 ) {
+    if ( result & 7 ) return -EIO;
+    if ( !callbacks ) continue;
+    for ( idx = 0; idx < result; idx += 8 ) {
+      cmd = *(unsigned int *)&buffer[ idx ];
+      tmp = *(unsigned int *)&buffer[ idx + 4 ];
+      if ( cmd == 0 && callbacks -> channel_was_changed ) {        
+        callbacks -> channel_was_changed( callbacks -> private_data, (int)tmp );
+      }
+    }
+    count += result >> 3;	/* return only number of changes */
+  }
+  return result >= 0 ? count : -errno;
+}