Merge pull request #244 from dnalor/input-shmem

Input shmem

README.md

@@ -40,6 +40,7 @@ thanks to [anko](https://github.com/anko) for the gif, here is the [recipe]( htt
   - [From ALSA-loopback device (Tricky)](#from-alsa-loopback-device-tricky)
   - [From mpd's fifo output](#from-mpds-fifo-output)
   - [sndio](#sndio)
+  - [squeezelite](#squeezelite)
 - [Running via ssh](#running-via-ssh)
 - [Font notes](#font-notes)
   - [In ttys](#in-ttys)
@@ -245,7 +246,15 @@ $ sndiod -dd -s default -m mon -s monitor
 $ AUDIODEVICE=snd/0.monitor cava
 ```
 
-
+### squeezelite
+[squeezelite](https://en.wikipedia.org/wiki/Squeezelite) is one of several software clients available for the Logitech Media Server. Squeezelite can export it's audio data as shared memory, which is what this input module uses.
+Configure C.A.V.A. with the `--enable-shmem` option, then adapt your config:
+```
+method = shmem
+source = /squeezelite-AA:BB:CC:DD:EE:FF
+```
+where `AA:BB:CC:DD:EE:FF` is squeezelite's MAC address (check the LMS Web GUI (Settings>Information) if unsure).
+Note: squeezelite must be started with the `-v` flag to enable visualizer support.
 
 Running via ssh
 ---------------

cava.c

@@ -63,6 +63,10 @@
 #include "input/sndio.c"
 #endif
 
+#ifdef SHMEM
+#include "input/shmem.c"
+#endif
+
 #include <iniparser.h>
 
 #include "config.h"
@@ -327,6 +331,9 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
     #ifdef SNDIO
         strcat(supportedInput,", 'sndio'");
     #endif
+    #ifdef SHMEM
+        strcat(supportedInput,", 'shmem'");
+    #endif
 
 	//fft: planning to rock
 	fftw_complex outl[M / 2 + 1];
@@ -441,6 +448,13 @@ as of 0.4.0 all options are specified in config file, see in '/home/username/.co
 	}
 	#endif
 
+	#ifdef SHMEM
+	if (p.im == 5) {
+		thr_id = pthread_create(&p_thread, NULL, input_shmem, (void*)&audio);
+		//audio.rate = 44100;
+	}
+	#endif
+
 	if (p.highcf > audio.rate / 2) {
 		cleanup();
 		fprintf(stderr,

config.c

@@ -160,6 +160,13 @@ if (strcmp(inputMethod, "sndio") == 0) {
 		return false;
 	#endif
 }
+if (strcmp(inputMethod, "shmem") == 0) {
+	p->im = 5;
+	#ifndef SHMEM
+		write_errorf(error, "cava was built without shmem support\n");
+		return false;
+	#endif
+}
 if (p->im == 0) {
 	write_errorf(error, "input method '%s' is not supported, supported methods are: %s\n",
 					inputMethod, supportedInput);
@@ -480,6 +487,12 @@ if (strcmp(inputMethod, "sndio") == 0) {
 	p->audio_source = (char *)iniparser_getstring(ini, "input:source", SIO_DEVANY);
 }
 #endif
+#ifdef SHMEM
+if (strcmp(inputMethod, "shmem") == 0) {
+	p->im = 5;
+	p->audio_source = (char *)iniparser_getstring(ini, "input:source", "/squeezelite-00:00:00:00:00:00");
+}
+#endif
 
 return validate_config(supportedInput, params, error);
 //iniparser_freedict(ini);

configure.ac

@@ -167,6 +167,24 @@ AS_IF([test "x$enable_legacy_iniparser" = "xyes"], [
   CPPFLAGS="$CPPFLAGS -DLEGACYINIPARSER"
 ])
 
+dnl ############################
+dnl checking if shared memory input is enabled
+dnl ############################
+
+AC_ARG_ENABLE([shmem],
+  AS_HELP_STRING([--enable-shmem],
+    [enable shared memory input (e.g. for squeezelite)])
+)
+
+AS_IF([test "x$enable_shmem" = "xyes"], [
+  dnl enabling shared memory input
+  AC_MSG_NOTICE([enabling shared memory input])
+  CPPFLAGS="$CPPFLAGS -DSHMEM"
+  LIBS="$LIBS -lrt"
+])
+
+
+
 dnl ############################
 dnl Set font directory
 dnl ############################

example_files/config

@@ -37,7 +37,7 @@
 
 [input]
 
-# Audio capturing method. Possible methods are: 'pulse', 'alsa', 'fifo' or 'sndio'.
+# Audio capturing method. Possible methods are: 'pulse', 'alsa', 'fifo', 'sndio' or 'shmem'
 # Defaults to 'pulse', 'alsa' or 'fifo', in that order, dependent on what support cava was built with.
 #
 # All input methods uses the same config variable 'source'
@@ -48,6 +48,7 @@
 # 
 # For alsa 'source' will be the capture device.
 # For fifo 'source' will be the path to fifo-file.
+# For shmem 'source' will be /squeezelite-AA:BB:CC:DD:EE:FF where 'AA:BB:CC:DD:EE:FF' will be squeezelite's MAC address
 ; method = pulse
 ; source = auto
 
@@ -57,6 +58,8 @@
 ; method = fifo
 ; source = /tmp/mpd.fifo
 
+; method = shmem
+; source = /squeezelite-AA:BB:CC:DD:EE:FF
 
 
 [output]

input/shmem.c

@@ -0,0 +1,91 @@
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <pthread.h>
+
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+
+typedef unsigned int u32_t;
+typedef short s16_t;
+
+
+// #define BUFSIZE 1024
+#define BUFSIZE 2048
+
+int rc;
+
+#define VIS_BUF_SIZE 16384
+#define VB_OFFSET 8192+4096
+
+typedef struct {
+	pthread_rwlock_t rwlock;
+	u32_t buf_size;
+	u32_t buf_index;
+	bool running;
+	u32_t rate;
+	time_t updated;
+	s16_t buffer[VIS_BUF_SIZE];
+}  vis_t;
+
+
+//input: SHMEM
+void* input_shmem(void* data)
+{
+	struct audio_data *audio = (struct audio_data *)data;
+	vis_t *mmap_area;
+	int fd; /* file descriptor to mmaped area */
+	int mmap_count = sizeof( vis_t);
+	int n = 0;
+	int i;
+
+	printf("input_shmem: source: %s", audio->source);
+
+	fd = shm_open(audio->source, O_RDWR, 0666);
+
+	if (fd < 0 ) {
+		printf("Could not open source '%s': %s\n", audio->source, strerror( errno ) );
+		exit(EXIT_FAILURE);
+	} else {
+		mmap_area = mmap(NULL, sizeof( vis_t), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+		if ((intptr_t)mmap_area == -1) {
+			printf("mmap failed - check if squeezelite is running with visualization enabled\n");
+			exit(EXIT_FAILURE);
+		}
+	}
+	// printf("bufs: %u / run: %u / rate: %u\n",mmap_area->buf_size, mmap_area->running, mmap_area->rate);
+	audio->rate = mmap_area->rate;
+
+	while (1) {
+		for (i = VB_OFFSET; i < BUFSIZE+VB_OFFSET; i += 2) {
+			if (audio->channels == 1) {
+				audio->audio_out_l[n] = (mmap_area->buffer[i] + mmap_area->buffer[i + 1]) / 2;
+			} else if (audio->channels == 2) {
+				audio->audio_out_l[n] = mmap_area->buffer[i];
+				audio->audio_out_r[n] = mmap_area->buffer[i + 1];
+			}
+			n++;
+			if (n == 2048 - 1) n = 0;
+		}
+		if (audio->terminate == 1) {
+			break;
+		}
+	}
+
+	// cleanup
+	if ( fd > 0 ) {
+		if ( close( fd ) != 0 ) {
+			printf("Could not close file descriptor %d: %s", fd, strerror( errno ) );
+		}
+	} else {
+		printf("Wrong file descriptor %d", fd );
+	}
+
+	if ( munmap( mmap_area, mmap_count ) != 0 ) {
+		printf("Could not munmap() area %p+%d. %s", mmap_area, mmap_count, strerror( errno ) );
+	}
+	return 0;
+}