added alsa

Original commit message from CVS:
added alsa

TODO

@@ -17,3 +17,4 @@
 
 * check options in a52, it has some arch stuff and some opti stuff that 
   looks dodgy
+

configure.ac

@@ -1152,6 +1152,7 @@ sys/xvideo/Makefile
 ext/Makefile
 ext/a52/Makefile
 ext/aalib/Makefile
+ext/alsa/Makefile
 ext/audiofile/Makefile
 ext/esd/Makefile
 ext/lame/Makefile

ext/Makefile.am

@@ -10,6 +10,12 @@ else
 AALIB_DIR=
 endif
 
+if USE_ALSA
+ALSA_DIR=alsa
+else
+ALSA_DIR=
+endif
+
 if USE_AUDIOFILE
 AUDIOFILE_DIR=audiofile
 else
@@ -47,8 +53,8 @@ VORBIS_DIR=
 endif
 
 
-SUBDIRS=$(A52_DIR) $(AALIB_DIR) $(AUDIOFILE_DIR) $(ESD_DIR) \
+SUBDIRS=$(A52_DIR) $(AALIB_DIR) $(ALSA_DIR) $(AUDIOFILE_DIR) $(ESD_DIR) \
         $(LAME_DIR) $(MAD_DIR) \
 	$(SDL_DIR) $(VORBIS_DIR)
 
-DIST_SUBDIRS=a52 aalib audiofile esd lame mad sdl vorbis
+DIST_SUBDIRS=a52 aalib alsa audiofile esd lame mad sdl vorbis

ext/alsa/Makefile.am

@@ -0,0 +1,13 @@
+plugindir = $(libdir)/gst
+
+plugin_LTLIBRARIES = libgstalsa.la
+
+libgstalsa_la_SOURCES = gstalsa.c
+
+noinst_HEADERS = gstalsa.h
+
+libgstalsa_la_CFLAGS = $(ALSA_CFLAGS) $(GST_CFLAGS)
+libgstalsa_la_LIBADD = $(ALSA_LIBS)
+
+EXTRA_DIST = README
+

ext/alsa/README

@@ -0,0 +1,64 @@
+0.0 History
+-----------
+
+This plugin was originally written by Thomas Nyberg <thomas@codefactory.se> for
+ALSA 0.5.x. It was updated and changed quite a bit in September 2001 by Andy
+Wingo for use with ALSA 0.9.x.
+
+1.0 Introduction
+----------------
+
+This plugin was designed for use with ALSA 0.9.x, using other versions most
+assuredly will not work.
+
+The plugin will probe which cards and pcm-devices that are availible, and then
+it tries to determine their capabilities. This will allow the use of multiple
+cards with multiple pcm-devices - at the same time! Since I only have one card
+on my system, as of yet, I haven't had the chance to try this out.
+
+2.0 How to use it
+-----------------
+
+Since we can have multiple soundcards, each having the same name - and also
+multiple pcm-devices on each card, a problem with naming occurs. When
+the alsa-plugins are initialized, a factory is created for each card and 
+pcm-device on the system. 
+
+On my desktop, I have the following:
+
+wingo@cebreiro:~/src/gstreamer$ gstreamer-inspect alsa
+INFO (  339:-1) Initializing GStreamer Core Library
+INFO (  339:-1) CPU features: (808009bf) MMX 3DNOW 
+Plugin Details:
+  Name:         alsa
+  Long Name:    Alsa plugin library
+  Filename:     /usr/lib/gst/libalsa.so
+
+  ES1370/1_sink: ES1370 DAC2/ADC
+  ES1370/2_sink: ES1370 DAC1
+  ES1370/1_src: ES1370 DAC2/ADC
+  alsasink: default alsa sink
+  alsasrc: default alsa src
+
+My particular card has 4 channel out and 2 channel in. As you can see, each of
+these devices are stereo. The alsasink and alsasrc elements correspond to the
+default alsa devices.
+
+3.0 License
+-----------
+
+ALSA 0.9.x isn't very well documented, so I had to rely on a number of different
+sources for guidance. One of the main sources of inspiration was Paul Davis'
+audioengine (available in quasimodo's cvs tree,
+http://quasimodo.sourceforge.net/), from which I took a large amount of code.
+Since that project is licensed under the GPL, it was only right that I license
+the updated version of this plugin under the GPL as well. What, in my
+understanding, this means for the end user is that you cannot use the ALSA
+plugin with a non-GPL program. If in doubt, please refer to the COPYING file
+located in this directory.
+
+
+
+
+
+

ext/alsa/gstalsa.h

@@ -0,0 +1,126 @@
+/*
+    Copyright (C) 2001 CodeFactory AB
+    Copyright (C) 2001 Thomas Nyberg <thomas@codefactory.se>
+    Copyright (C) 2001 Andy Wingo <apwingo@eos.ncsu.edu>
+                            
+    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 library 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.
+*/
+
+#ifndef __GST_ALSA_H__
+#define __GST_ALSA_H__
+
+#include <sys/asoundlib.h>
+#include <gst/gst.h>
+#include <libs/bytestream/gstbytestream.h>
+#include <glib.h>
+
+#define GST_ALSA(obj) G_TYPE_CHECK_INSTANCE_CAST(obj, GST_TYPE_ALSA, GstAlsa)
+#define GST_ALSA_CLASS(klass) G_TYPE_CHECK_CLASS_CAST(klass, GST_TYPE_ALSA, GstAlsaClass)
+#define GST_IS_ALSA(obj) G_TYPE_CHECK_INSTANCE_TYPE(obj, GST_TYPE_ALSA)
+#define GST_IS_ALSA_CLASS(klass) G_TYPE_CHECK_CLASS_TYPE(klass, GST_TYPE_ALSA)
+#define GST_TYPE_ALSA gst_alsa_get_type()
+
+#define GST_ALSA_SINK(obj) G_TYPE_CHECK_INSTANCE_CAST(obj, GST_TYPE_ALSA_SINK, GstAlsa)
+#define GST_ALSA_SINK_CLASS(klass) G_TYPE_CHECK_CLASS_CAST(klass, GST_TYPE_ALSA_SINK, GstAlsaClass)
+#define GST_IS_ALSA_SINK(obj) G_TYPE_CHECK_INSTANCE_TYPE(obj, GST_TYPE_ALSA_SINK)
+#define GST_IS_ALSA_SINK_CLASS(klass) G_TYPE_CHECK_CLASS_TYPE(klass, GST_TYPE_ALSA_SINK)
+#define GST_TYPE_ALSA_SINK gst_alsa_sink_get_type()
+
+#define GST_ALSA_SRC(obj) G_TYPE_CHECK_INSTANCE_CAST(obj, GST_TYPE_ALSA_SRC, GstAlsa)
+#define GST_ALSA_SRC_CLASS(klass) G_TYPE_CHECK_CLASS_CAST(klass, GST_TYPE_ALSA_SRC, GstAlsaClass)
+#define GST_IS_ALSA_SRC(obj) G_TYPE_CHECK_INSTANCE_TYPE(obj, GST_TYPE_ALSA_SRC)
+#define GST_IS_ALSA_SRC_CLASS(klass) G_TYPE_CHECK_CLASS_TYPE(klass, GST_TYPE_ALSA_SRC)
+#define GST_TYPE_ALSA_SRC gst_alsa_src_get_type()
+
+#define GST_ALSA_PAD(obj) ((GstAlsaPad*)obj->data) /* obj is a GList */
+
+/* I would have preferred to avoid this variety of trickery, but without it i
+ * can't tell whether I'm a source or a sink upon creation. */
+
+typedef struct _GstAlsa GstAlsa;
+typedef struct _GstAlsaClass GstAlsaClass;
+typedef GstAlsa GstAlsaSink;
+typedef GstAlsaClass GstAlsaSinkClass;
+typedef GstAlsa GstAlsaSrc;
+typedef GstAlsaClass GstAlsaSrcClass;
+
+enum {
+    GST_ALSA_OPEN = GST_ELEMENT_FLAG_LAST,
+    GST_ALSA_RUNNING,
+    GST_ALSA_FLAG_LAST = GST_ELEMENT_FLAG_LAST + 3,
+};
+
+typedef gboolean (*GstAlsaProcessFunc) (GstAlsa *, snd_pcm_uframes_t frames);
+
+typedef struct {
+    gint channel;
+    GstPad *pad;
+    GstByteStream *bs;
+    /* pointer to where we can access mmap_areas */
+    char *access_addr;
+    char *buf;
+    /* how much of the buffer we have used */
+    snd_pcm_uframes_t offset;
+} GstAlsaPad;
+
+struct _GstAlsa {
+    GstElement parent;
+
+    /* list of GstAlsaPads */
+    GList *pads;
+    
+    gchar *device;
+    snd_pcm_stream_t stream;
+    
+    snd_pcm_t *handle;
+    snd_output_t *out;
+    
+    /* our mmap'd data areas */
+    gboolean mmap_open;
+    const snd_pcm_channel_area_t *mmap_areas;
+    char **access_addr;
+    snd_pcm_uframes_t offset;
+    snd_pcm_sframes_t avail;
+    
+    GstAlsaProcessFunc process;
+    
+    snd_pcm_format_t format;
+    guint rate;
+    gint channels;
+    guint32 mute; /* bitmask. */
+    
+    /* the gstreamer data */
+    gboolean data_interleaved;
+    
+    /* access to the hardware */
+    gboolean access_interleaved;
+    guint sample_bytes;
+    guint interleave_unit;
+    guint interleave_skip;
+    
+    guint buffer_frames;
+    guint period_count; /* 'number of fragments' in oss-speak */
+    guint period_frames;
+};
+
+struct _GstAlsaClass {
+    GstElementClass parent_class;
+};
+
+GType gst_alsa_get_type (void);
+GType gst_alsa_sink_get_type (void);
+GType gst_alsa_src_get_type (void);
+
+#endif /* __ALSA_H__ */