/*
 * echo_test.c
 *
 *  Created on: Oct 4, 2014
 *      Author: etsam
 */

/*
 * Test application that data integraty of inter processor
 * communication from linux userspace to a remote software
 * context. The application sends chunks of data to the
 * remote processor. The remote side echoes the data back
 * to application which then validates the data returned.
 */

#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <time.h>
#include <fcntl.h>
#include <string.h>
#include <linux/rpmsg.h>

struct _payload {
	unsigned long num;
	unsigned long size;
	char data[];
};

static int charfd = -1, fd = -1, err_cnt;

struct _payload *i_payload;
struct _payload *r_payload;

#define RPMSG_GET_KFIFO_SIZE 1
#define RPMSG_GET_AVAIL_DATA_SIZE 2
#define RPMSG_GET_FREE_SPACE 3

#define RPMSG_HEADER_LEN 16
#define MAX_RPMSG_BUFF_SIZE (512 - RPMSG_HEADER_LEN)
#define PAYLOAD_MIN_SIZE	1
#define PAYLOAD_MAX_SIZE	(MAX_RPMSG_BUFF_SIZE - 24)
#define NUM_PAYLOADS		(PAYLOAD_MAX_SIZE/PAYLOAD_MIN_SIZE)

#define RPMSG_BUS_SYS "/sys/bus/rpmsg"

static int rpmsg_create_ept(int rpfd, struct rpmsg_endpoint_info *eptinfo)
{
	int ret;

	ret = ioctl(rpfd, RPMSG_CREATE_EPT_IOCTL, eptinfo);
	if (ret)
		perror("Failed to create endpoint.\n");
	return ret;
}

static char *get_rpmsg_ept_dev_name(const char *rpmsg_char_name,
				    const char *ept_name,
				    char *ept_dev_name)
{
	char sys_rpmsg_ept_name_path[64];
	char svc_name[64];
	char *sys_rpmsg_path = "/sys/class/rpmsg";
	FILE *fp;
	int i;
	int ept_name_len;

	for (i = 0; i < 128; i++) {
		sprintf(sys_rpmsg_ept_name_path, "%s/%s/rpmsg%d/name",
			sys_rpmsg_path, rpmsg_char_name, i);
		printf("checking %s\n", sys_rpmsg_ept_name_path);
		if (access(sys_rpmsg_ept_name_path, F_OK) < 0)
			continue;
		fp = fopen(sys_rpmsg_ept_name_path, "r");
		if (!fp) {
			printf("failed to open %s\n", sys_rpmsg_ept_name_path);
			break;
		}
		fgets(svc_name, sizeof(svc_name), fp);
		fclose(fp);
		printf("svc_name: %s.\n",svc_name);
		ept_name_len = strlen(ept_name);
		if (ept_name_len > sizeof(svc_name))
			ept_name_len = sizeof(svc_name);
		if (!strncmp(svc_name, ept_name, ept_name_len)) {
			sprintf(ept_dev_name, "rpmsg%d", i);
			return ept_dev_name;
		}
	}

	printf("Not able to RPMsg endpoint file for %s:%s.\n",
	       rpmsg_char_name, ept_name);
	return NULL;
}

static int bind_rpmsg_chrdev(const char *rpmsg_dev_name)
{
	char fpath[256];
	char *rpmsg_chdrv = "rpmsg_chrdev";
	int fd;
	int ret;


	/* rpmsg dev overrides path */
	sprintf(fpath, "%s/devices/%s/driver_override",
		RPMSG_BUS_SYS, rpmsg_dev_name);
	fd = open(fpath, O_WRONLY);
	if (fd < 0) {
		fprintf(stderr, "Failed to open %s, %s\n",
			fpath, strerror(errno));
		return -EINVAL;
	}
	ret = write(fd, rpmsg_chdrv, strlen(rpmsg_chdrv) + 1);
	if (ret < 0) {
		fprintf(stderr, "Failed to write %s to %s, %s\n",
			rpmsg_chdrv, fpath, strerror(errno));
		return -EINVAL;
	}
	close(fd);

	/* bind the rpmsg device to rpmsg char driver */
	sprintf(fpath, "%s/drivers/%s/bind", RPMSG_BUS_SYS, rpmsg_chdrv);
	fd = open(fpath, O_WRONLY);
	if (fd < 0) {
		fprintf(stderr, "Failed to open %s, %s\n",
			fpath, strerror(errno));
		return -EINVAL;
	}
	ret = write(fd, rpmsg_dev_name, strlen(rpmsg_dev_name) + 1);
	if (ret < 0) {
		fprintf(stderr, "Failed to write %s to %s, %s\n",
			rpmsg_dev_name, fpath, strerror(errno));
		return -EINVAL;
	}
	close(fd);
	return 0;
}

static int get_rpmsg_chrdev_fd(const char *rpmsg_dev_name,
			       char *rpmsg_ctrl_name)
{
	char dpath[256];
	char fpath[256];
	char *rpmsg_ctrl_prefix = "rpmsg_ctrl";
	DIR *dir;
	struct dirent *ent;
	int fd;

	sprintf(dpath, "%s/devices/%s/rpmsg", RPMSG_BUS_SYS, rpmsg_dev_name);
	dir = opendir(dpath);
	if (dir == NULL) {
		fprintf(stderr, "Failed to open dir %s\n", dpath);
		return -EINVAL;
	}
	while ((ent = readdir(dir)) != NULL) {
		if (!strncmp(ent->d_name, rpmsg_ctrl_prefix,
			    strlen(rpmsg_ctrl_prefix))) {
			printf("Opening file %s.\n", ent->d_name);
			sprintf(fpath, "/dev/%s", ent->d_name);
			fd = open(fpath, O_RDWR | O_NONBLOCK);
			if (fd < 0) {
				fprintf(stderr,
					"Failed to open rpmsg char dev %s,%s\n",
					fpath, strerror(errno));
				return fd;
			}
			sprintf(rpmsg_ctrl_name, "%s", ent->d_name);
			return fd;
		}
	}

	fprintf(stderr, "No rpmsg char dev file is found\n");
	return -EINVAL;
}

int main(int argc, char *argv[])
{
	int ret, i, j;
	int size, bytes_rcvd, bytes_sent;
	err_cnt = 0;
	int opt;
	char *rpmsg_dev="virtio0.rpmsg-openamp-demo-channel.-1.0";
	int ntimes = 1;
	char fpath[256];
	char rpmsg_char_name[16];
	struct rpmsg_endpoint_info eptinfo;
	char ept_dev_name[16];
	char ept_dev_path[32];


	while ((opt = getopt(argc, argv, "d:n:")) != -1) {
		switch (opt) {
		case 'd':
			rpmsg_dev = optarg;
			break;
		case 'n':
			ntimes = atoi(optarg);
			break;
		default:
			printf("getopt return unsupported option: -%c\n",opt);
			break;
		}
	}
	printf("\r\n Echo test start \r\n");

	/* Load rpmsg_char driver */
	printf("\r\nMaster>probe rpmsg_char\r\n");
	ret = system("modprobe rpmsg_char");
	if (ret < 0) {
		perror("Failed to load rpmsg_char driver.\n");
		return -EINVAL;
	}

	printf("\r\n Open rpmsg dev %s! \r\n", rpmsg_dev);
	sprintf(fpath, "%s/devices/%s", RPMSG_BUS_SYS, rpmsg_dev);
	if (access(fpath, F_OK)) {
		fprintf(stderr, "Not able to access rpmsg device %s, %s\n",
			fpath, strerror(errno));
		return -EINVAL;
	}
	ret = bind_rpmsg_chrdev(rpmsg_dev);
	if (ret < 0)
		return ret;
	charfd = get_rpmsg_chrdev_fd(rpmsg_dev, rpmsg_char_name);
	if (charfd < 0)
		return charfd;

	/* Create endpoint from rpmsg char driver */
	strcpy(eptinfo.name, "rpmsg-openamp-demo-channel");
	eptinfo.src = 0;
	eptinfo.dst = 0xFFFFFFFF;
	ret = rpmsg_create_ept(charfd, &eptinfo);
	if (ret) {
		printf("failed to create RPMsg endpoint.\n");
		return -EINVAL;
	}
	if (!get_rpmsg_ept_dev_name(rpmsg_char_name, eptinfo.name,
				    ept_dev_name))
		return -EINVAL;
	sprintf(ept_dev_path, "/dev/%s", ept_dev_name);
	fd = open(ept_dev_path, O_RDWR | O_NONBLOCK);
	if (fd < 0) {
		perror("Failed to open rpmsg device.");
		close(charfd);
		return -1;
	}

	i_payload = (struct _payload *)malloc(2 * sizeof(unsigned long) + PAYLOAD_MAX_SIZE);
	r_payload = (struct _payload *)malloc(2 * sizeof(unsigned long) + PAYLOAD_MAX_SIZE);

	if (i_payload == 0 || r_payload == 0) {
		printf("ERROR: Failed to allocate memory for payload.\n");
		return -1;
	}

	for (j=0; j < ntimes; j++){
		printf("\r\n **********************************");
		printf("****\r\n");
		printf("\r\n  Echo Test Round %d \r\n", j);
		printf("\r\n **********************************");
		printf("****\r\n");
		for (i = 0, size = PAYLOAD_MIN_SIZE; i < NUM_PAYLOADS;
		i++, size++) {
			int k;

			i_payload->num = i;
			i_payload->size = size;

			/* Mark the data buffer. */
			memset(&(i_payload->data[0]), 0xA5, size);

			printf("\r\n sending payload number");
			printf(" %ld of size %d\r\n", i_payload->num,
			(2 * sizeof(unsigned long)) + size);

			bytes_sent = write(fd, i_payload,
			(2 * sizeof(unsigned long)) + size);

			if (bytes_sent <= 0) {
				printf("\r\n Error sending data");
				printf(" .. \r\n");
				break;
			}
			printf("echo test: sent : %d\n", bytes_sent);

			r_payload->num = 0;
			bytes_rcvd = read(fd, r_payload,
					(2 * sizeof(unsigned long)) + PAYLOAD_MAX_SIZE);
			while (bytes_rcvd <= 0) {
				usleep(10000);
				bytes_rcvd = read(fd, r_payload,
					(2 * sizeof(unsigned long)) + PAYLOAD_MAX_SIZE);
			}
			printf(" received payload number ");
			printf("%ld of size %d\r\n", r_payload->num, bytes_rcvd);

			/* Validate data buffer integrity. */
			for (k = 0; k < r_payload->size; k++) {

				if (r_payload->data[k] != 0xA5) {
					printf(" \r\n Data corruption");
					printf(" at index %d \r\n", k);
					err_cnt++;
					break;
				}
			}
			bytes_rcvd = read(fd, r_payload,
			(2 * sizeof(unsigned long)) + PAYLOAD_MAX_SIZE);

		}
		printf("\r\n **********************************");
		printf("****\r\n");
		printf("\r\n Echo Test Round %d Test Results: Error count = %d\r\n",
		j, err_cnt);
		printf("\r\n **********************************");
		printf("****\r\n");
	}

	free(i_payload);
	free(r_payload);

	close(fd);
	if (charfd >= 0)
		close(charfd);
	return 0;
}