nms plugins example

/* 

HOW TO BUILD:
Source neuros-env then run:
arm-linux-gcc -o srvlink srvlink.c -lncooler-core -lncooler-media -L$PRJROOT/toolchain/arm-linux/lib -DBUILD_TARGET_ARM -I$PRJROOT/toolchain/arm-linux/include

- Other TODOs in the file
*/

#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>

#include "cooler-core.h"
#include "cooler-media.h"

#define SAMPLERATE 44100
#define CHANNELS 2
#define READ_SIZE 4096 /* (1024 * 4) */
#define SLEEP_NO_BUFFERS 100

//TODO: most of this stuff shall be moved as into the nmsplugin.h public interface of cooler-media
typedef void * (*plugin_interface_get) (void);
#define NEUROS_OUTPUT_PLUGIN_INTERFACE "GetNmsOutputPlugin"
//END TODO
#define NEUROS_OUTPUT_PLUGIN_PATH NMS_PLUGIN_DIR "libdm320nmso.so"

static media_desc_t output_mode_info = {
		.adesc = {
			.audio_type = NMS_AC_PCM,
			.num_channels = CHANNELS,
			.sample_rate = SAMPLERATE,
			.bitrate = CHANNELS * SAMPLERATE * 16,
		},
		.vdesc = {
			.video_type = NMS_VC_NO_VIDEO,
			.width = 0,
			.height = 0,
			.frame_rate = 0,
		},
		.sdesc = {
			.subtitle_type = NMS_SC_NO_SUBTITLE,
		},
	};
static media_buf_t buf;
static media_output_plugin_t * plugin;
static int plugin_inited = 0;

#define cleanup() cleanup_(1)
static void cleanup_(int startmonitor) 
{
    if (plugin_inited) plugin->finish(1);
    if (startmonitor) NmsStartMonitor();
}

static void signal_handler(int signum)
{
	printf("------- Exiting on signal [%d] --------\n", signum);
    cleanup();
	exit(0);
}

static void signal_init(void)
{
	struct sigaction sa;
	
	memset(&sa, 0, sizeof(sa));
	sa.sa_handler = signal_handler;
	
    if (sigaction(SIGHUP, &sa, NULL)){}
    if (sigaction(SIGINT, &sa, NULL)){}
    if (sigaction(SIGABRT, &sa, NULL)){}
    if (sigaction(SIGQUIT, &sa, NULL)){}
    if (sigaction(SIGTERM, &sa, NULL)){}
}

static media_output_plugin_t * LoadNMSPlugin()
{
    void * plugin_lib;
    void * interface_get;

    plugin_lib = dlopen(NEUROS_OUTPUT_PLUGIN_PATH, RTLD_LAZY);
    if (plugin_lib == NULL) {
        printf ("Neuros Output Plugin is not in %s\n", NEUROS_OUTPUT_PLUGIN_PATH);
        return NULL;
    }

    interface_get = dlsym(plugin_lib, NEUROS_OUTPUT_PLUGIN_INTERFACE);
    if (interface_get == NULL) {
        printf ("Neuros Output Plugin has interface symbol %d\n", NEUROS_OUTPUT_PLUGIN_INTERFACE);
        return NULL;
    }

    plugin = (media_output_plugin_t *) (((plugin_interface_get)interface_get)());
    if (plugin == NULL) {
        printf ("Neuros Output Plugin did not return plugin interface\n");
        return NULL;
    }
    else {
        printf("Neuros Ouput Plugin loaded: \"%s\" ver \"%s\" descr: \"%d\"\n", 
        plugin->brief, plugin->ver, plugin->description );
    }

    return plugin;
}

static int reads = 0;

int main()
{
    media_output_plugin_t * plugin;
    int ret;

    plugin = LoadNMSPlugin();
    if (plugin == NULL) return -1;

    //I stop the monitor since this is holding the dm320 I/O locked.
    if (NmsConnect() == 0) { printf("Stopping monitor.."); NmsStopMonitor(); printf(".stopped\n");}
    else printf("No connection to nmsd\n");

    //initialize plugin for doing only direct PCM-audio-only output
    //second param (mode) doesn't really matter as it's NTSC/PAL for video
    printf("calling plugin->init\n");
    ret = plugin->init(&output_mode_info, 0);
    if (ret == -1) {
        printf(".failed\n");
        cleanup();
        return -1;
	} else if (ret == 1) {
		printf(".output locked\n");
		cleanup_(0);
		return -2;
    } else { 
        plugin_inited = 1;
        printf(".success\n");
    }

    FILE* f = fopen("/media/USB/test.raw", "r");
    int bytes = -1;
    memset(&buf, sizeof(buf), 0);

    if (f == NULL) {
        printf("Test file failed to open\n");
        cleanup();
        return -1;
    }

    printf("-------- calling plugin->start ----------\n");
    ret = plugin->start();
    if (ret == -1) {
        printf("plugin->start failed\n");
        cleanup();
        return -1;
    }

    while ( reads++ < 1000 )
    {
        //Get output buffers (2st param = timeout, 3rd param = "we're not preloading")
        ret = plugin->getBuffer(&buf, 0, 0);
        //printf("Output buffer returned\tvbuf-size = %u \tabuf-size = %u \tsbuf-size = %u \n", buf.vbuf.size, buf.abuf.size, buf.sbuf.size);
        if (ret == 1)
        {
            printf("No empty buffers available right now, sleeping %d\n", SLEEP_NO_BUFFERS);
            continue;
        } else if (ret < 0) {
            printf("ERROR: plugin->getBuffer failed\n");
            cleanup();
            return -1;
        }
        if (buf.abuf.size > 0) {
            bytes = fread(buf.abuf.data, 1, READ_SIZE, f);
            buf.curbuf = &buf.abuf;
            buf.abuf.size = bytes;
            if (bytes <= 0) break;
        } else {
            cleanup();
            printf("ERROR: plugin->getBuffer returned zero-length audio buffer\n");
            return -1;
        }
        plugin->write(&buf);
    }
    
    fclose(f);
    cleanup();

    printf("------- Exiting normally --------\n");
    return 0;
}