simpleaudio: pulseaudio and libsndfile backends

src/Makefile.am

@@ -5,8 +5,13 @@ INCLUDES = $(DEPS_CFLAGS)
 
 bin_PROGRAMS = minimodem tscope
 
+SIMPLEAUDIO_SRC=\
+	simpleaudio.c		\
+	simpleaudio-pulse.c	\
+	simpleaudio-sndfile.c
+
 minimodem_LDADD = $(DEPS_LIBS)
-minimodem_SOURCES = minimodem.c tscope_print.c
+minimodem_SOURCES = minimodem.c tscope_print.c $(SIMPLEAUDIO_SRC)
 
 tscope_LDADD = $(DEPS_LIBS)
 tscope_SOURCES = tscope.c tscope_print.c

src/Makefile.in

@@ -45,7 +45,10 @@ CONFIG_CLEAN_FILES =
 CONFIG_CLEAN_VPATH_FILES =
 am__installdirs = "$(DESTDIR)$(bindir)"
 PROGRAMS = $(bin_PROGRAMS)
-am_minimodem_OBJECTS = minimodem.$(OBJEXT) tscope_print.$(OBJEXT)
+am__objects_1 = simpleaudio.$(OBJEXT) simpleaudio-pulse.$(OBJEXT) \
+	simpleaudio-sndfile.$(OBJEXT)
+am_minimodem_OBJECTS = minimodem.$(OBJEXT) tscope_print.$(OBJEXT) \
+	$(am__objects_1)
 minimodem_OBJECTS = $(am_minimodem_OBJECTS)
 am__DEPENDENCIES_1 =
 minimodem_DEPENDENCIES = $(am__DEPENDENCIES_1)
@@ -155,8 +158,13 @@ top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 AM_CFLAGS = -Wall -Werror
 INCLUDES = $(DEPS_CFLAGS)
+SIMPLEAUDIO_SRC = \
+	simpleaudio.c		\
+	simpleaudio-pulse.c	\
+	simpleaudio-sndfile.c
+
 minimodem_LDADD = $(DEPS_LIBS)
-minimodem_SOURCES = minimodem.c tscope_print.c
+minimodem_SOURCES = minimodem.c tscope_print.c $(SIMPLEAUDIO_SRC)
 tscope_LDADD = $(DEPS_LIBS)
 tscope_SOURCES = tscope.c tscope_print.c
 all: all-am
@@ -244,6 +252,9 @@ distclean-compile:
 	-rm -f *.tab.c
 
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/minimodem.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/simpleaudio-pulse.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/simpleaudio-sndfile.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/simpleaudio.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/tscope.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/tscope_print.Po@am__quote@
 

src/simpleaudio-pulse.c

@@ -0,0 +1,90 @@
+
+#include <stdio.h>
+#include <malloc.h>
+#include <assert.h>
+
+#include <pulse/simple.h>
+#include <pulse/error.h>
+#include <pulse/gccmacro.h>
+
+#include "simpleaudio.h"
+#include "simpleaudio_internal.h"
+
+
+/*
+ * pulseaudio[pa_simple] backend for simpleaudio
+ */
+
+
+static size_t
+sa_pulse_read( simpleaudio *sa, float *buf, size_t nframes )
+{
+    int error;
+    pa_simple *s = (pa_simple *)sa->backend_handle;
+    size_t nbytes = nframes * sa->backend_framesize;
+    int n;
+    if ((n = pa_simple_read(s, buf, nbytes, &error)) < 0) {
+	fprintf(stderr, "pa_simple_read: %s\n", pa_strerror(error));
+	return -1;
+    }
+    return n;
+}
+
+
+static void
+sa_pulse_close( simpleaudio *sa )
+{
+    pa_simple_free(sa->backend_handle);
+}
+
+
+static const struct simpleaudio_backend simpleaudio_backend_pulse = {
+    sa_pulse_read,
+    sa_pulse_close,
+};
+
+simpleaudio *
+simpleaudio_open_source_pulseaudio(
+		// unsigned int rate, unsigned int channels,
+		char *app_name, char *stream_name )
+{
+    int error;
+
+    // FIXME - use source for something
+    // just take the default pulseaudio source for now
+
+    /* The sample type to use */
+    pa_sample_spec ss = {
+        .format = PA_SAMPLE_FLOAT32,
+	// .rate = rate,
+	.rate = 48000,
+	// .channels = channels,
+	.channels = 1,
+    };
+
+    /* Create the recording stream */
+    pa_simple *s;
+    s = pa_simple_new(NULL, app_name, PA_STREAM_RECORD, NULL, stream_name,
+	    &ss, NULL, NULL, &error);
+    if ( !s ) {
+        fprintf(stderr, "pa_simple_new: %s\n", pa_strerror(error));
+        return NULL;
+    }
+
+    simpleaudio *sa = malloc(sizeof(simpleaudio));
+    if ( !sa ) {
+	perror("malloc");
+	pa_simple_free(s);
+        return NULL;
+    }
+    sa->rate = ss.rate;
+    sa->channels = ss.channels;
+    sa->backend = &simpleaudio_backend_pulse;
+    sa->backend_handle = s;
+    sa->backend_framesize = pa_frame_size(&ss);
+
+    assert( sa->backend_framesize == ss.channels * sizeof(float) );
+
+    return sa;
+}
+

src/simpleaudio-sndfile.c

@@ -0,0 +1,74 @@
+
+#include <stdio.h>
+#include <malloc.h>
+#include <assert.h>
+
+#include <sndfile.h>
+
+#include "simpleaudio.h"
+#include "simpleaudio_internal.h"
+
+
+/*
+ * sndfile backend for simpleaudio
+ */
+
+
+static size_t
+sa_sndfile_read( simpleaudio *sa, float *buf, size_t nframes )
+{
+    SNDFILE *s = (SNDFILE *)sa->backend_handle;
+    int n;
+    if ((n = sf_readf_float(s, buf, nframes)) < 0) {
+	fprintf(stderr, "sf_read_float: ");
+	sf_perror(s);
+	return -1;
+    }
+//fprintf(stderr, "sf_read_float: nframes=%ld n=%d\n", nframes, n);
+    return n;
+}
+
+
+static void
+sa_sndfile_close( simpleaudio *sa )
+{
+    sf_close(sa->backend_handle);
+}
+
+
+static const struct simpleaudio_backend simpleaudio_backend_pulse = {
+    sa_sndfile_read,
+    sa_sndfile_close,
+};
+
+simpleaudio *
+simpleaudio_open_source_sndfile(char *path)
+{
+    SF_INFO sfinfo = {
+	.format = 0
+    };
+
+    /* Create the recording stream */
+    SNDFILE *s;
+    s = sf_open(path, SFM_READ, &sfinfo);
+    if ( !s ) {
+	fprintf(stderr, "%s: ", path);
+	sf_perror(s);
+        return NULL;
+    }
+
+    simpleaudio *sa = malloc(sizeof(simpleaudio));
+    if ( !sa ) {
+	perror("malloc");
+	sf_close(s);
+        return NULL;
+    }
+    sa->rate = sfinfo.samplerate;
+    sa->channels = sfinfo.channels;
+    sa->backend = &simpleaudio_backend_pulse;
+    sa->backend_handle = s;
+    sa->backend_framesize = sa->channels * sizeof(float);
+
+    return sa;
+}
+

src/simpleaudio.c

@@ -0,0 +1,28 @@
+#include "simpleaudio.h"
+#include "simpleaudio_internal.h"
+#include "malloc.h"
+
+unsigned int
+simpleaudio_get_rate( simpleaudio *sa )
+{
+    return sa->rate;
+}
+
+unsigned int
+simpleaudio_get_channels( simpleaudio *sa )
+{
+    return sa->channels;
+}
+
+size_t
+simpleaudio_read( simpleaudio *sa, float *buf, size_t nframes )
+{
+    return sa->backend->simpleaudio_read(sa, buf, nframes);
+}
+
+void
+simpleaudio_close( simpleaudio *sa )
+{
+    sa->backend->simpleaudio_close(sa);
+    free(sa);
+}

src/simpleaudio.h

@@ -0,0 +1,40 @@
+#ifndef SIMPLEAUDIO_H
+#define SIMPLEAUDIO_H
+
+#include <sys/types.h>
+
+struct simpleaudio;
+typedef struct simpleaudio simpleaudio;
+
+/*
+ * simpleaudio_open_source_XXXX() routines which return a (simpleaudio *)
+ * are provided by the separate backend modules.
+ *
+ */
+
+simpleaudio *
+simpleaudio_open_source_pulseaudio(
+		// unsigned int rate, unsigned int channels,
+		char *app_name, char *stream_name );
+
+simpleaudio *
+simpleaudio_open_source_sndfile(char *path);
+
+/*
+ * common simpleaudio_ API routines available to any backend:
+ */
+
+unsigned int
+simpleaudio_get_rate( simpleaudio *sa );
+
+unsigned int
+simpleaudio_get_channels( simpleaudio *sa );
+
+size_t
+simpleaudio_read( simpleaudio *sa, float *buf, size_t nframes );
+
+void
+simpleaudio_close( simpleaudio *sa );
+
+
+#endif

src/simpleaudio_internal.h

@@ -0,0 +1,31 @@
+#ifndef SIMPLEAUDIO_INTERNAL_H
+#define SIMPLEAUDIO_INTERNAL_H
+
+
+#include "simpleaudio.h"
+
+/*
+ * Backend modules must provide an "open" routine which returns a
+ * (simpleaudio *) to the caller.
+ */
+
+struct simpleaudio_backend;
+typedef struct simpleaudio_backend simpleaudio_backend;
+
+struct simpleaudio {
+	const struct simpleaudio_backend	*backend;
+	unsigned int	rate;
+	unsigned int	channels;
+	void *		backend_handle;
+	unsigned int	backend_framesize;
+};
+
+struct simpleaudio_backend {
+	size_t
+	(*simpleaudio_read)( simpleaudio *sa, float *buf, size_t nframes );
+	void
+	(*simpleaudio_close)( simpleaudio *sa );
+};
+
+
+#endif