From 9d1e78667201d5e2b1e499d7ae15ffd1950868e3 Mon Sep 17 00:00:00 2001
From: Radek Matejka <radek.matejka@gmail.com>
Date: Mon, 6 Aug 2012 17:00:51 +0200
Subject: [PATCH] first version of cegwbench

---
 utils/cegwbench/Makefile    |   3 +
 utils/cegwbench/cegwbench.c | 179 ++++++++++++++++++++++++++++++++++++
 2 files changed, 182 insertions(+)
 create mode 100644 utils/cegwbench/Makefile
 create mode 100644 utils/cegwbench/cegwbench.c

diff --git a/utils/cegwbench/Makefile b/utils/cegwbench/Makefile
new file mode 100644
index 0000000..68ca59e
--- /dev/null
+++ b/utils/cegwbench/Makefile
@@ -0,0 +1,3 @@
+all:
+	gcc -Wall -ocegwbench -lrt cegwbench.c
+
diff --git a/utils/cegwbench/cegwbench.c b/utils/cegwbench/cegwbench.c
new file mode 100644
index 0000000..dba10dd
--- /dev/null
+++ b/utils/cegwbench/cegwbench.c
@@ -0,0 +1,179 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <math.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <net/if.h>
+#include <arpa/inet.h>
+#include <linux/can.h>
+#include <pthread.h>
+
+/**
+ * ToDo:
+ * [ ] consider can timestamp
+ */
+
+struct optdata
+{
+	int n;
+};
+
+struct optdata d;
+pthread_barrier_t barrier;
+struct timespec* tx_time, * rx_time;
+
+void* udp_recv( void* arg )
+{
+	struct sockaddr_in sa_udp;
+	int udp_sock;
+	struct can_frame cf;
+	int i;
+
+	sa_udp.sin_family = AF_INET;
+	sa_udp.sin_port = htons( 10502 );
+	inet_aton( "127.0.0.1", &sa_udp.sin_addr );
+
+	udp_sock = socket( PF_INET, SOCK_DGRAM, IPPROTO_UDP );
+	if( udp_sock < 0 )
+	{
+		fprintf( stderr, "error: udp socket creation failed\n" );
+		return NULL;
+	}
+
+	if( bind(udp_sock, (struct sockaddr*)&sa_udp, sizeof(sa_udp)) != 0 )
+	{
+		fprintf( stderr, "error: udp socket binding failed\n" );
+		return NULL;
+	}
+
+	pthread_barrier_wait( &barrier );
+
+	/* recv */
+	for( i=0; i<d.n; i++ )
+	{
+		recvfrom( udp_sock, &cf, sizeof(cf), 0, NULL, 0 );
+		clock_gettime( CLOCK_REALTIME, &rx_time[cf.data[0]] );
+		printf( "recv: (id=%d)%u\n", cf.can_id, cf.data[0] );
+	}
+
+	close( udp_sock );
+	return NULL;
+}
+
+int timespec_subtract( struct timespec *result, struct timespec *x, struct timespec *yy )
+{
+	struct timespec ylocal = *yy, *y = &ylocal;
+	/* Perform the carry for the later subtraction by updating Y. */
+	if( x->tv_nsec < y->tv_nsec )
+	{
+		int nsec = (y->tv_nsec - x->tv_nsec) / 1000000000 + 1;
+		y->tv_nsec -= 1000000000 * nsec;
+		y->tv_sec += nsec;
+		}
+	if (x->tv_nsec - y->tv_nsec > 1000000000) {
+		int nsec = (x->tv_nsec - y->tv_nsec) / 1000000000;
+		y->tv_nsec += 1000000000 * nsec;
+		y->tv_sec -= nsec;
+	}
+
+	/* Compute the time remaining to wait.
+	 * 	   `tv_nsec' is certainly positive. */
+	result->tv_sec = x->tv_sec - y->tv_sec;
+	result->tv_nsec = x->tv_nsec - y->tv_nsec;
+	/* Return 1 if result is negative. */
+	return x->tv_sec < y->tv_sec;
+}
+
+int main( int argc, char* argv[] )
+{
+	char opt;
+	struct sockaddr_can sa_can;
+	struct can_frame cf;
+	int can_sock;
+	pthread_t thr;
+	float mean = 0;
+	float time;
+	struct timespec res;
+	int i;
+
+	while( 1 )
+	{
+		opt = getopt( argc, argv, "n:" );
+		if( opt == -1 )
+			break;
+		switch( opt )
+		{
+			case 'n':
+				d.n = atoi( optarg );
+				break;
+			case '?':
+				return -1;
+				break;
+		}
+	}
+
+	tx_time = malloc( d.n*sizeof(struct timespec) );
+	rx_time = malloc( d.n*sizeof(struct timespec) );
+
+	pthread_barrier_init( &barrier, NULL, 2 );
+	pthread_create( &thr, NULL, udp_recv, NULL  );
+
+	sa_can.can_family = AF_CAN;
+	sa_can.can_ifindex = if_nametoindex( "vcan0" );
+	
+	can_sock = socket( PF_CAN, SOCK_RAW, CAN_RAW );
+	if( can_sock < 0 )
+	{
+		fprintf( stderr, "error: can socket creation failed\n" );
+		return -1;
+	}
+
+	if( bind(can_sock, (struct sockaddr*)&sa_can, sizeof(sa_can)) != 0 )
+	{
+		fprintf( stderr, "error: can socket binding failed\n" );
+		return -1;
+	}
+
+	pthread_barrier_wait( &barrier );
+
+	/* send  */
+	for( i=0; i<d.n; i++ )
+	{
+		//memset( &cf, 0, sizeof(cf) );
+		cf.can_id = i;
+		cf.can_dlc = 8;
+		cf.data[0] = i;
+		int ret = sendto( can_sock, &cf, sizeof(cf), 0, (struct sockaddr*)&sa_can, sizeof(sa_can) );
+		clock_gettime( CLOCK_REALTIME, &tx_time[cf.data[0]] );
+		printf( "sending(%d)\n", ret );
+	}
+
+	close( can_sock ); /* shutdown? */
+	pthread_join( thr, NULL );
+
+	/* results */
+	for( i=0; i<d.n; i++ )
+	{
+		if( timespec_subtract( &res, &rx_time[i], &tx_time[i] ) == 0 )
+		{
+			time = res.tv_sec*1000000000.0f + (float)res.tv_nsec;
+			mean += time;
+			printf( "transfer time:%fns\n", time );
+		} else
+		{
+			printf( "transfer time: irrelevant\n" );
+		}
+	}
+	mean /= ++i;
+	printf( "average: %fns\n", mean );
+
+	free( tx_time );
+	free( rx_time );
+//	clock_gettime( CLOCK_REALTIME, &tx_time );
+
+	return 0;
+}
+
-- 
2.39.2