taller abierto # 4 - LDC - Universidad Simón Bolívar

Universidad Simón Bolívar
Departamento de Computación y Tecnología de la Información
Redes de Computadores (CI-4835)
TALLER ABIERTO # 4
RECURSOS REQUERIDOS: Para la ejecución de esta práctica el estudiante deberá
disponer un PC ejecutando Linux® y el Software para programar RPC.
DURACIÓN: 2 horas
ACTIVIDADES A REALIZAR:
Parte 1: El profesor expondrá a los estudiantes cómo funciona RPC y RMI. Para ello se
apoyará en las láminas que se proveen con este material.
Parte 2: El estudiante examinará el ejemplo que abajo se muestra, luego lo compilará y
ejecutará hasta ver cómo funciona en la práctica.
A.- Archivo “rand.h”:
/* Please do not edit this file.
It was generated using rpcgen. */
#ifndef _RAND_H_RPCGEN
#define _RAND_H_RPCGEN
#include <rpc/rpc.h>
#ifdef __cplusplus
extern "C" {
#endif
#define RAND_PROG 0x31111111
#define RAND_VERS 1
#if defined(__STDC__) || defined(__cplusplus)
#define INITIALIZE_RANDOM 1
extern void * initialize_random_1(long *, CLIENT *);
extern void * initialize_random_1_svc(long *, struct svc_req *);
#define GET_NEXT_RANDOM 2
extern double * get_next_random_1(void *, CLIENT *);
extern double * get_next_random_1_svc(void *, struct svc_req *);
extern int rand_prog_1_freeresult (SVCXPRT *, xdrproc_t, caddr_t);
#else /* K&R C */
#define INITIALIZE_RANDOM 1
extern void * initialize_random_1();
extern void * initialize_random_1_svc();
#define GET_NEXT_RANDOM 2
extern double * get_next_random_1();
extern double * get_next_random_1_svc();
extern int rand_prog_1_freeresult ();
#endif /* K&R C */
#ifdef __cplusplus
}
#endif
#endif /* !_RAND_H_RPCGEN */
B.- Archivo “rand.x”:
/*
rand.x
*/
program RAND_PROG {
version RAND_VERS {
void INITIALIZE_RANDOM(long)=1;
double GET_NEXT_RANDOM(void)=2;
}=1;
}= 0x31111111;
C.- Archivo “rand_client.c”:
#include <stdlib.h>
#include <stdio.h>
#include "rand.h"
int main (int argc, char *argv[])
{
char *host;
CLIENT *clnt;
void *result_1;
double *result_2;
char *get_next_random_1_arg;
long semilla;
int i, iters;
if (argc != 4) {
fprintf (stderr, "uso: %s servidor semilla iteraciones\n", argv[0]);
exit (1);
}
host = argv[1];
semilla = (long) atoi(argv[2]);
iters = atoi(argv[3]);
clnt = clnt_create (host, RAND_PROG, RAND_VERS, "udp");
if (clnt == NULL) {
clnt_pcreateerror (host);
exit (1);
}
result_1 = initialize_random_1(&semilla, clnt);
if (result_1 == (void *) NULL) {
clnt_perror (clnt, "call failed");
exit (2);
}
for (i=0; i<iters ;i++) {
result_2 = get_next_random_1((void*)&get_next_random_1_arg, clnt);
if (result_2 == (double *) NULL) {
clnt_perror (clnt, "call failed");
exit (3);
} else
printf("%d: %f\n", i, *result_2);
}
clnt_destroy(clnt);
exit (0);
}
D.- Archivo “rand_clnt.c”:
/* Please do not edit this file.
It was generated using rpcgen. */
#include <memory.h> /* for memset */
#include "rand.h"
/* Default timeout can be changed using clnt_control() */
static struct timeval TIMEOUT = { 25, 0 };
void * initialize_random_1(long *argp, CLIENT *clnt)
{
static char clnt_res;
memset((char *)&clnt_res, 0, sizeof(clnt_res));
if (clnt_call (clnt, INITIALIZE_RANDOM,
(xdrproc_t) xdr_long, (caddr_t) argp,
(xdrproc_t) xdr_void, (caddr_t) &clnt_res,
TIMEOUT) != RPC_SUCCESS) {
return (NULL);
}
return ((void *)&clnt_res);
}
double * get_next_random_1(void *argp, CLIENT *clnt)
{
static double clnt_res;
memset((char *)&clnt_res, 0, sizeof(clnt_res));
if (clnt_call (clnt, GET_NEXT_RANDOM,
(xdrproc_t) xdr_void, (caddr_t) argp,
(xdrproc_t) xdr_double, (caddr_t) &clnt_res,
TIMEOUT) != RPC_SUCCESS) {
return (NULL);
}
return (&clnt_res);
}
E.- Archivo “rand_server.c”:
#include <stdlib.h>
#include "rand.h"
void * initialize_random_1_svc(long *argp, struct svc_req *rqstp)
{
static char * result;
srand48(*argp);
result=(void *)NULL;
return (void *) &result;
}
double * get_next_random_1_svc(void *argp, struct svc_req *rqstp)
{
static double result;
result=drand48();
return &result;
}
F.- Archivo “rand_svc.c”:
/* Please do not edit this file.
It was generated using rpcgen. */
#include
#include
#include
#include
#include
#include
#include
#include
"rand.h"
<stdio.h>
<stdlib.h>
<rpc/pmap_clnt.h>
<string.h>
<memory.h>
<sys/socket.h>
<netinet/in.h>
#ifndef SIG_PF
#define SIG_PF void(*)(int)
#endif
static void rand_prog_1(struct svc_req *rqstp, register SVCXPRT *transp)
{
union {
long initialize_random_1_arg;
} argument;
char *result;
xdrproc_t _xdr_argument, _xdr_result;
char *(*local)(char *, struct svc_req *);
switch (rqstp->rq_proc) {
case NULLPROC:
(void) svc_sendreply (transp, (xdrproc_t) xdr_void, (char *)NULL);
return;
case INITIALIZE_RANDOM:
_xdr_argument = (xdrproc_t) xdr_long;
_xdr_result = (xdrproc_t) xdr_void;
local = (char *(*)(char *, struct svc_req *)) initialize_random_1_svc;
break;
case GET_NEXT_RANDOM:
_xdr_argument = (xdrproc_t) xdr_void;
_xdr_result = (xdrproc_t) xdr_double;
local = (char *(*)(char *, struct svc_req *)) get_next_random_1_svc;
break;
default:
svcerr_noproc (transp);
return;
}
memset ((char *)&argument, 0, sizeof (argument));
if (!svc_getargs (transp, (xdrproc_t) _xdr_argument, (caddr_t) &argument)) {
svcerr_decode (transp);
return;
}
result = (*local)((char *)&argument, rqstp);
if (result != NULL && !svc_sendreply(transp, (xdrproc_t) _xdr_result, result)) {
svcerr_systemerr (transp);
}
if (!svc_freeargs (transp, (xdrproc_t) _xdr_argument, (caddr_t) &argument)) {
fprintf (stderr, "%s", "unable to free arguments");
exit (1);
}
return;
}
int main (int argc, char **argv)
{
register SVCXPRT *transp;
pmap_unset (RAND_PROG, RAND_VERS);
transp = svcudp_create(RPC_ANYSOCK);
if (transp == NULL) {
fprintf (stderr, "%s", "cannot create udp service.");
exit(1);
}
if (!svc_register(transp, RAND_PROG, RAND_VERS, rand_prog_1, IPPROTO_UDP)) {
fprintf (stderr, "%s", "unable to register (RAND_PROG, RAND_VERS, udp).");
exit(1);
}
transp = svctcp_create(RPC_ANYSOCK, 0, 0);
if (transp == NULL) {
fprintf (stderr, "%s", "cannot create tcp service.");
exit(1);
}
if (!svc_register(transp, RAND_PROG, RAND_VERS, rand_prog_1, IPPROTO_TCP)) {
fprintf (stderr, "%s", "unable to register (RAND_PROG, RAND_VERS, tcp).");
exit(1);
}
svc_run ();
fprintf (stderr, "%s", "svc_run returned");
exit (1);
/* NOTREACHED */
}
G.- Archivo “Makefile.rand”:
# This is a template Makefile generated by rpcgen
# Parameters
CLIENT = rand_client
SERVER = rand_server
SOURCES_CLNT.c =
SOURCES_CLNT.h =
SOURCES_SVC.c =
SOURCES_SVC.h =
SOURCES.x = rand.x
TARGETS_SVC.c = rand_svc.c rand_server.c
TARGETS_CLNT.c = rand_clnt.c rand_client.c
TARGETS = rand.h rand_clnt.c rand_svc.c rand_client.c rand_server.c
OBJECTS_CLNT = $(SOURCES_CLNT.c:%.c=%.o) $(TARGETS_CLNT.c:%.c=%.o)
OBJECTS_SVC = $(SOURCES_SVC.c:%.c=%.o) $(TARGETS_SVC.c:%.c=%.o)
# Compiler flags
CFLAGS += -g
LDLIBS += -lnsl
RPCGENFLAGS =
# Targets
all : $(CLIENT) $(SERVER)
$(TARGETS) : $(SOURCES.x)
rpcgen $(RPCGENFLAGS) $(SOURCES.x)
$(OBJECTS_CLNT) : $(SOURCES_CLNT.c) $(SOURCES_CLNT.h) $(TARGETS_CLNT.c)
$(OBJECTS_SVC) : $(SOURCES_SVC.c) $(SOURCES_SVC.h) $(TARGETS_SVC.c)
$(CLIENT) : $(OBJECTS_CLNT)
$(LINK.c) -o $(CLIENT) $(OBJECTS_CLNT) $(LDLIBS)
$(SERVER) : $(OBJECTS_SVC)
$(LINK.c) -o $(SERVER) $(OBJECTS_SVC) $(LDLIBS)
clean:
$(RM) core $(TARGETS) $(OBJECTS_CLNT) $(OBJECTS_SVC) $(CLIENT) $(SERVER)
Grupo Docente de Redes de Computadoras I / Ene-Mar 2014