Makefile

@@ -0,0 +1,58 @@
+all:
+	@echo "Usage: make <commande>"
+	@echo ""
+	@echo "Commandes disponibles:"
+	@echo "- worm_inc : version modifiée des programmes, avec insertion de detect_init()"
+	@echo "              et bibliothèque de détection de pannes liée statiquement"
+	@echo "- worm_shared : version modifiée des programmes, avec insertion de detect_init()"
+	@echo "                 et bibliothèque de détection de pannes liée dynamiquement"
+	@echo "- worm_preload: version non modifiée des programmes, avec préchargement de la "
+	@echo "                 bibliothèque de détection de pannes, et execution de celle-ci."
+	
+worm_inc: clean server
+	gcc -ggdb -o worms_mod libdetect.c worms_mod.c -lcurses -lrt -lpthread -Wall
+	gcc -ggdb -o test_mod libdetect.c test_mod.c  -lrt -lpthread -Wall
+	@echo -e "\n*  Pour executer, taper: "
+	@echo -e "*\n*    ./worms_mod"
+	@echo -e "*\n*  ou "
+	@echo -e "*\n*    ./test_mod\n*"
+
+worm_shared: clean server
+	gcc -fPIC -Wall -ggdb -c libdetect.c
+	gcc -g -shared -Wl,-soname,libdetect.so.0 \
+	    -o libdetect.so.0.0 libdetect.o -lc
+	/sbin/ldconfig -n .
+	ln -sf libdetect.so.0 libdetect.so
+	gcc -Wall -ggdb -o test_shr test_mod.c -L. -lrt -lpthread -ldetect
+	gcc -Wall -ggdb -o worms_shr worms_mod.c -L. -lcurses -lrt -lpthread -ldetect
+	@echo -e "\n*  Pour executer, taper: "
+	@echo -e "*\n*    LD_LIBRARY_PATH="." ./worms_shr"
+	@echo -e "*\n*  ou "
+	@echo -e "*\n*    LD_LIBRARY_PATH="." ./test_shr\n*"
+
+# run with:
+#   LD_LIBRARY_PATH="." ./command
+
+
+worm_preload: clean server
+	gcc -fPIC -Wall -ggdb -c libdetect.c  -D_GYR_PRELOAD
+	gcc -g -shared -Wl,-soname,libdetect.so.0 \
+	    -o libdetect.so.0.0 libdetect.o -lc
+	/sbin/ldconfig -n .
+	ln -sf libdetect.so.0 libdetect.so
+	gcc -ggdb -o worms worms.c -lcurses -lrt -lpthread -Wall
+	gcc -ggdb -o test test.c  -lrt -lpthread -Wall
+	@echo -e "\n*  Pour executer, taper: "
+	@echo -e "*\n*    LD_LIBRARY_PATH="." LD_PRELOAD=libdetect.so ./worms"
+	@echo -e "*\n*  ou "
+	@echo -e "*\n*    LD_LIBRARY_PATH="." LD_PRELOAD=libdetect.so ./test\n*"
+
+server:
+	gcc -ggdb -o detector-server detector-server.c -Wall
+
+clean:
+	rm -f *.so*
+	rm -f *.o
+	rm -f detector-server
+	rm -f test test_mod test_shr
+	rm -f worms worms_mod worms_shr

README

@@ -0,0 +1,35 @@
+
+Prérequis: L'utilisation de ce projet nécessite un système GNU/Linux, et la
+présence du compilateur GNU GCC
+
+
+
+    make <commande>
+
+* Détecteur de pannes, invoqué depuis main
+
+  Taper:
+  
+    make worm_inc
+
+  et suivre les instructions.
+
+
+* Détecteur de pannes, invoqué depuis main et compilé
+  dans une bibliothèque chargée dynamiquement
+
+  Taper:
+
+    make worm_shared
+
+  et suivre les instructions.
+
+* Détecteur de pannes, dans une bibliothèque chargée
+  dynamiquement, mais sans toucher au code source du programme original.
+
+  Taper:
+
+    make worm_preload
+
+  et suivre les instructions.
+

detector-server.c

@@ -0,0 +1,348 @@
+#include <pthread.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#define LINK_CELL_NAME_SIZE		100
+
+#define KEEP_SOCK_MAX(x, y)	if (x < ((y) +1)){ x = (y) + 1; }
+
+#define FOREACH_SOCKET_IN_SOCKBASKET(i, sockbasket, link)	for (i = 0; \
+																((i < sockbasket->size) \
+																 && (link_basket_get(sockbasket, i, &link)) \
+																 ); \
+																i++) \
+															if (link != NULL) 
+
+#define SELECT_TIMEOUT		100000;
+#define REQUEST_INTERVAL 	5
+#define REQUEST_TIMEOUT		30
+
+#define MIN(x, y)		(((x) < (y))?(x):(y))
+
+#define bool	short
+#define true	1
+#define false 	0
+
+typedef struct {
+	int sock_desc;
+	bool is_dead;
+	bool is_alive;
+	bool is_registered;
+	time_t request_stamp;
+	time_t answer_stamp;
+	char * name;
+} link_cell_t;
+
+typedef struct {
+	link_cell_t ** data;
+	int size;
+	int next;
+} link_basket_t;
+
+void show_progress(){
+	static int prog = 0;
+	prog = prog % 100;
+	printf("[");
+	if (prog < 25){
+		printf("|");
+	} else if (prog < 50) {
+		printf("/");
+	} else if (prog < 75) {
+		printf("-");
+	} else {
+		printf("\\");
+	}
+	printf("] ");
+	prog += 25;
+}
+bool link_basket_get (link_basket_t *sb, int index, link_cell_t ** res){
+	bool result;
+	if (index < sb->size){
+		*res = sb->data[ index ];
+		/* 
+		if (*res != NULL){
+			printf ("Get at %d == %d\n", index, (*res)->sock_desc);
+		} */
+		result = 1;
+	} else {
+		*res = NULL;
+		result = 0;
+	}
+	return result;	
+}
+
+void link_basket_delete (link_basket_t * sb){
+	free (sb->data);
+	free (sb);
+}
+
+void link_basket_remove (link_basket_t * sb, int index){
+	link_cell_t * result = sb->data[ index ];
+	if (sb->data[ index ]){
+		free(result->name);
+		free (result);
+	}
+	sb->data[ index ] = NULL;
+	if (index < sb->next){
+		sb->next = index;
+	}
+	return;
+}
+
+void link_basket_add (link_basket_t * sb, int sockfd){
+	int i;
+
+	assert (sb->next != -1); // basket overflow !
+
+	link_cell_t * cell = (link_cell_t *) malloc (sizeof (link_cell_t));
+
+	cell->sock_desc = sockfd;
+	cell->is_dead = false;
+	cell->is_alive = true;
+	cell->is_registered = false;
+	cell->request_stamp = time(NULL);
+	cell->answer_stamp = time(NULL);
+	cell->name = (char *) malloc (sizeof (char) * LINK_CELL_NAME_SIZE);
+	memset(cell->name, 0, LINK_CELL_NAME_SIZE);
+
+	sb->data[ sb->next ] = cell;
+
+	for (i = sb->next; i < sb->size; i++){
+		if (sb->data[ i ] == NULL){
+			sb->next = i;
+		}
+	}
+	return;
+}
+
+link_basket_t * link_basket_create (int size){
+	link_basket_t * result =
+		(link_basket_t *) malloc (sizeof (link_basket_t));
+	result->size = size;
+	result->data = (link_cell_t **) malloc (sizeof (link_cell_t *) * size);
+	result->next = 0;
+
+	int i;
+	for (i = 0; i < result->size; i++){
+		result->data[i] = NULL;
+	}
+	return result;
+}
+
+int main (){
+	link_basket_t * basket = link_basket_create(10);
+
+	int main_sock ;
+	int port;
+	char * hostname;
+	char * portstr;
+	struct hostent * server;
+	struct sockaddr_in * myaddr;
+
+	main_sock = socket (AF_INET, SOCK_STREAM, 0);
+	if (main_sock < 0){
+		perror ("Creation de la socket impossible");
+		fprintf (stderr,"BOOM at %s:%d\n",__FILE__,__LINE__);
+		exit (-1);
+	}
+
+	hostname = getenv ("DETECTOR_HOSTNAME"); 
+	portstr = getenv ("DETECTOR_PORT"); 
+	if ((NULL == hostname) || (NULL == portstr)){
+		printf("Environment variables DETECTOR_PORT and DETECTOR_HOSTNAME should have been defined.\n");
+		exit(-1);
+	}
+	sscanf (portstr, "%d", &port);
+
+
+	printf ("Lookup for %s...\n", hostname);
+	server = gethostbyname(hostname);
+	if (server == NULL){
+		fprintf (stderr, "Error, no such host\n");
+		exit (-1);
+	}
+	printf ("Host found\n");
+
+
+	myaddr = 
+		(struct sockaddr_in *) malloc (sizeof(struct sockaddr_in));
+	bzero (myaddr, sizeof(struct sockaddr_in));
+	myaddr->sin_family = AF_INET;
+	myaddr->sin_port = htons(port);
+
+	memcpy (&(myaddr->sin_addr.s_addr), server->h_addr, sizeof(u_long)); 
+	//myaddr->sin_addr.s_addr = INADDR_ANY;
+
+	// on bind sur le port voulu...
+	if (bind(main_sock, (struct sockaddr *)myaddr, sizeof(struct sockaddr)) < 0){
+		perror("Unable to bind");
+		fprintf(stderr,"Cannot bind on port %d of %s\n",port, inet_ntoa(myaddr->sin_addr));
+		exit(-1);
+	} else {
+		printf("Bind on port %d of %s\n",port, inet_ntoa(myaddr->sin_addr));
+	}
+
+	// on fait un listen
+	if (listen(main_sock, 10) < 0){
+		perror("Unable to listen");
+		exit(-1);
+	} else {
+		printf("Ready to accept connexions.\n");
+	}
+
+	fd_set sock_set;
+	struct timeval tv;
+	int sock_set_size = 0;
+
+	FD_ZERO(&sock_set);
+	FD_SET(main_sock, &sock_set);
+	sock_set_size++;
+
+	
+	while(1){
+		printf("\r");
+		show_progress();
+		
+		tv.tv_sec = 0;
+		tv.tv_usec = SELECT_TIMEOUT;
+		//
+		// si on recoit qqchose sur la socket principale, on fait un accept
+		// et on ajoute la nouvelle socket au set
+		link_cell_t * link;
+		int i;
+
+		fd_set read_set;//= sock_set;
+		FD_ZERO(&read_set);
+		FD_SET(main_sock, &read_set);
+		KEEP_SOCK_MAX(sock_set_size, main_sock);
+
+
+		// on ajoute tous les socket ouverts au read_set
+		FOREACH_SOCKET_IN_SOCKBASKET (i, basket, link) {
+			time_t curtime = time(NULL);
+			bool must_add = false;
+			if (link->is_registered){
+				if (link->is_alive){
+					// si le programme est en vie
+					if (difftime(curtime, link->answer_stamp) > REQUEST_INTERVAL){
+						//   si le temps nécessaire est écoulé depuis la derniere réponse
+						printf ("\nRequesting liveness for '%s'\n", link->name);
+
+						send(link->sock_desc,"status?", 7, 0);
+						link->request_stamp = curtime;
+						link->is_alive = false;
+						must_add = true;
+					} else {
+						//   sinon on attend le temps nécessaire avant de douter...
+						// printf ("On attend que le temps s'écoule pour '%s'\n", link->name);
+					}
+				} else {
+					// sinon
+					if (difftime(curtime, link->request_stamp) > REQUEST_TIMEOUT){
+						//   ou on le tue...
+						// FIXME: retirer de la corbeille a liens...	
+						printf ("\nTimeout: closing connection of '%s'\n", link->name);
+						close(link->sock_desc);
+						link_basket_remove(basket, i);
+					} else {
+						//   on est toujours dans les temps de réponse...
+						//printf ("\nWaiting for '%s'\n", link->name);
+						must_add = true;
+					}
+				}
+
+			} else {
+				must_add = true;
+			}
+
+			if (must_add){
+				//printf ("Adding '%s' (%d) to the set\n", link->name, link->sock_desc);
+				FD_SET (link->sock_desc, &read_set);
+				KEEP_SOCK_MAX (sock_set_size, link->sock_desc);
+			}
+		}
+
+		printf("Select..."); fflush(stdout);
+		select(sock_set_size, &read_set, NULL, NULL, &tv); 
+		printf("done"); fflush(stdout);
+
+		FOREACH_SOCKET_IN_SOCKBASKET(i, basket, link) {
+			time_t curtime = time(NULL);
+
+			if (FD_ISSET(link->sock_desc, &read_set)){
+				// on lit les données recues, et sinon on ferme la socket.
+				// on vérifie qu'elle sont égales à ...
+				int buffer_len = 1024;
+				char * buffer = (char *) malloc (sizeof(char) * buffer_len);
+				int recv_len;
+				recv_len = recv(link->sock_desc, buffer, buffer_len, 0);
+
+				if (recv_len == 0){
+					printf("\nClient '%s' has disconnected !\n", link->name);
+					link_basket_remove(basket, i);
+				} else {
+					if ((recv_len >= 9) && (!strncmp("register:", buffer, 9))) {
+						buffer[MIN(recv_len, buffer_len - 1)] = '\0';
+
+						int i=0;
+						while(i < buffer_len -1){
+							if ((buffer[i] == 0xD)  || (buffer[i] == 0xA)) { buffer[i] = '\0'; }
+							i++;
+						}
+						strncpy(link->name, buffer + 9, MIN(recv_len - 9, LINK_CELL_NAME_SIZE));
+						printf("\nRegistering client : %s\n", link->name);
+						link->is_registered = true;
+						link->answer_stamp = curtime;
+
+					} else if ((recv_len >= 6) && (!strncmp("alive!", buffer, 6))) {
+						//printf("Process on fd %d is alive !\n", link->sock_desc);
+						link->is_alive = true;
+						link->answer_stamp = curtime;
+
+					} else {
+						buffer[99] = '\0';
+						printf("\nUnknow message %s", buffer);
+					}
+				}
+
+			} else {
+				// printf("Rien sur %d\n", link->sock_desc);
+			}
+		}
+
+		if (FD_ISSET(main_sock, &read_set)){
+			unsigned int sin_size = sizeof(struct sockaddr_in);
+			struct sockaddr_in their_addr; /* Adresse du connecté  */
+			int sockfd;
+
+			sockfd = accept(main_sock, (struct sockaddr *)&their_addr, 
+					&sin_size);
+			link_basket_add(basket, sockfd);
+			printf("\nGot new connection at %d\n", sockfd);
+		};
+
+
+		// lors d'un accept, on ajoute au tableau des entrées
+		// possibles l'hote qui se connecte
+
+		// regarder les entrées...
+		// faire un select dessus
+		// garde des timer pour chaque entrée
+		// lorsque le temps D est écoule pour un timer
+		// on envoie un paquet "WIEGEHTS" a la machine
+		// et on attend une réponse en moins de 60 sec;
+
+	}
+	return EXIT_SUCCESS;
+}

libdetect.c

@@ -0,0 +1,130 @@
+
+#include <pthread.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef _GYR_PRELOAD
+void __attribute__ ((constructor)) detector_init(void);
+#endif
+
+typedef struct {
+	char * hostname;
+	int port;
+} detector_serv_t;
+
+void * detector_thread_fun(void * paramvoid){
+	detector_serv_t * param = paramvoid;
+
+	printf("Thread launched\n");
+	// se connecter
+	int socket_desc = socket(AF_INET, SOCK_STREAM, 0);
+	if (socket_desc < 0){
+		perror("Creation de la socket impossible");
+		fprintf(stderr,"BOUM at %s:%d\n",__FILE__,__LINE__);
+		exit(-1);
+	}
+	
+	printf("Lookup for %s...\n", param->hostname);
+	struct hostent * server = gethostbyname(param->hostname);
+	if (server == NULL){
+		fprintf(stderr, "Error, no such host\n");
+		exit(-1);
+	}
+
+	printf("Host found\n");
+	
+	struct sockaddr_in * myaddr = 
+		(struct sockaddr_in *) malloc (sizeof(struct sockaddr_in));
+	bzero(myaddr, sizeof(struct sockaddr_in));
+	myaddr->sin_family = AF_INET;
+	myaddr->sin_port = htons(param->port);
+
+	memcpy (&(myaddr->sin_addr.s_addr), server->h_addr, sizeof(u_long)); 
+	// myaddr->sin_addr.s_addr = server->h_addr[0];
+
+	/*
+	   bcopy((char *)(server->h_addr),
+	   (char *)(myaddr->sin_addr.s_addr),
+	   server->h_length);
+	 */
+
+	if (connect(socket_desc, 
+				(struct sockaddr *)myaddr, 
+				sizeof(struct sockaddr_in)) < 0){
+		perror("Attachement de la socket impossible");
+		fprintf(stderr,"No connect at %s:%d\n",__FILE__,__LINE__);	
+		exit(-1);
+	}
+	printf("Thread connected\n");
+
+	char hostname[50];
+	gethostname(hostname, 50);
+	char ident[100];
+	sprintf(ident, "%d@%s", getpid(), hostname);
+
+	char * message = (char *) malloc (sizeof(char) * 1024);
+	memset(message, 0, 1024);
+	sprintf(message, "register:%s\n", ident);
+
+	write(socket_desc, message, strlen(message)); 
+
+	// indiquer au serveur qu'il faut qu'il vérifie ce prog
+	// identifant pid
+	while(1){
+		// on attend "status?", on répond "alive!"
+		int recv_len;
+		memset(message, 0, 1024);
+		recv_len = recv (socket_desc, message, 1024, 0);
+
+		if (!strncmp("status?", message, 7)){
+			send (socket_desc, "alive!", 6, 0);
+		}
+
+	}
+	// se déconnecter ?
+
+}
+
+void detector_init(){
+	// créer un thread "a part" qui répond au serveur
+	// et retourner dans le programme principal
+	pthread_t thr_detector;
+	pthread_attr_t thr_att;
+
+	pthread_attr_init(&thr_att);
+
+	detector_serv_t * param = (detector_serv_t *)
+		malloc (sizeof(detector_serv_t));
+	// FIXME: read environment variable
+	param->hostname = getenv("DETECTOR_HOSTNAME");
+	if (param->hostname == NULL){
+		fprintf(stderr,"Undefined envirnoment variable DETECTOR_HOSTNAME\n");
+	}
+
+	//FIXME: read env variable
+	char * portstr = getenv("DETECTOR_PORT");
+	if (portstr == NULL){
+		fprintf(stderr,"Undefined envirnoment variable DETECTOR_HOSTNAME\n");
+	}
+	sscanf(portstr, "%d", &(param->port));
+	printf("HOST (%s) PORT (%d)\n", param->hostname, param->port);
+
+	if (pthread_create (&thr_detector,
+				&thr_att,
+				detector_thread_fun, 
+				param))
+	{
+		perror("Impossible de créer le thread\n");
+		exit(-1);
+	}
+
+}

test.c

@@ -0,0 +1,11 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+
+int main(){
+	while(1){
+		sleep(1);
+		printf("Loooooping \n");
+	}
+}

test_mod.c

@@ -0,0 +1,13 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+void detector_init();
+
+int main(){
+	detector_init();
+	while(1){
+		sleep(1);
+		printf("Loooooping \n");
+	}
+}

tip-macosx.txt

@@ -0,0 +1,24 @@
+
+EXO 3  (pour macosX)
+-------------------------------------------------------
+gcc -dynamiclib -std=gnu99 -current-version 1.0
+	-compatibility_version 1.0 -fvisibility=hidden
+	-o (lib)Detect.A.dylib *.c
+
+#define EXPORT __attribute__((visibility("default"))
+
+
+EXPORT: 
+	void detect_init(){ }
+
+EXO 4 (pour macosX)
+-------------------------------------------------------
+__attribute__((constructor))
+	static void initializer(void)
+}
+
+
+EXO 5 (pour macosX)
+-------------------------------------------------------
+DYLD_INSERT_LIBRARIES = ./libDetect.A.dylib
+

worms.c

@@ -0,0 +1,344 @@
+/*
+ * Copyright (c) 1980, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static const char copyright[] =
+"@(#) Copyright (c) 1980, 1993\n\
+		The Regents of the University of California.  All rights reserved.\n";
+#endif /* not lint */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)worms.c	8.1 (Berkeley) 5/31/93";
+#endif
+static const char rcsid[] =
+"$FreeBSD: /repoman/r/ncvs/src/games/worms/worms.c,v 1.11 2002/02/23 10:35:25 billf Exp $";
+#endif /* not lint */
+
+/*
+ *
+ *	 @@@        @@@    @@@@@@@@@@     @@@@@@@@@@@    @@@@@@@@@@@@
+ *	 @@@        @@@   @@@@@@@@@@@@    @@@@@@@@@@@@   @@@@@@@@@@@@@
+ *	 @@@        @@@  @@@@      @@@@   @@@@           @@@@ @@@  @@@@
+ *	 @@@   @@   @@@  @@@        @@@   @@@            @@@  @@@   @@@
+ *	 @@@  @@@@  @@@  @@@        @@@   @@@            @@@  @@@   @@@
+ *	 @@@@ @@@@ @@@@  @@@        @@@   @@@            @@@  @@@   @@@
+ *	  @@@@@@@@@@@@   @@@@      @@@@   @@@            @@@  @@@   @@@
+ *	   @@@@  @@@@     @@@@@@@@@@@@    @@@            @@@  @@@   @@@
+ *	    @@    @@       @@@@@@@@@@     @@@            @@@  @@@   @@@
+ *
+ *				 Eric P. Scott
+ *			  Caltech High Energy Physics
+ *				 October, 1980
+ *
+ */
+#include <sys/types.h>
+#include <curses.h>
+#include <err.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static const struct options {
+	int nopts;
+	int opts[3];
+}
+normal[8] = {
+	{ 3, { 7, 0, 1 } },
+	{ 3, { 0, 1, 2 } },
+	{ 3, { 1, 2, 3 } },
+	{ 3, { 2, 3, 4 } },
+	{ 3, { 3, 4, 5 } },
+	{ 3, { 4, 5, 6 } },
+	{ 3, { 5, 6, 7 } },
+	{ 3, { 6, 7, 0 } }
+},	upper[8] = {
+	{ 1, { 1, 0, 0 } },
+	{ 2, { 1, 2, 0 } },
+	{ 0, { 0, 0, 0 } },
+	{ 0, { 0, 0, 0 } },
+	{ 0, { 0, 0, 0 } },
+	{ 2, { 4, 5, 0 } },
+	{ 1, { 5, 0, 0 } },
+	{ 2, { 1, 5, 0 } }
+},
+	left[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 2, { 2, 3, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 2, { 3, 7, 0 } },
+		{ 1, { 7, 0, 0 } },
+		{ 2, { 7, 0, 0 } }
+	},
+	right[8] = {
+		{ 1, { 7, 0, 0 } },
+		{ 2, { 3, 7, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 2, { 3, 4, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 2, { 6, 7, 0 } }
+	},
+	lower[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 2, { 0, 1, 0 } },
+		{ 1, { 1, 0, 0 } },
+		{ 2, { 1, 5, 0 } },
+		{ 1, { 5, 0, 0 } },
+		{ 2, { 5, 6, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } }
+	},
+	upleft[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 2, { 1, 3, 0 } },
+		{ 1, { 1, 0, 0 } }
+	},
+	upright[8] = {
+		{ 2, { 3, 5, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 5, 0, 0 } }
+	},
+	lowleft[8] = {
+		{ 3, { 7, 0, 1 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 1, 0, 0 } },
+		{ 2, { 1, 7, 0 } },
+		{ 1, { 7, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } }
+	},
+	lowright[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 7, 0, 0 } },
+		{ 2, { 5, 7, 0 } },
+		{ 1, { 5, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } }
+	};
+
+
+static const char	flavor[] = {
+	'O', '*', '#', '$', '%', '0', '@', '~'
+};
+static const short	xinc[] = {
+	1,  1,  1,  0, -1, -1, -1,  0
+}, yinc[] = {
+	-1,  0,  1,  1,  1,  0, -1, -1
+};
+static struct	worm {
+	int orientation, head;
+	short *xpos, *ypos;
+} *worm;
+
+volatile sig_atomic_t sig_caught = 0;
+void	nomem(void);
+void	onsig(int);
+
+int main(int argc, char *argv[])
+{
+	int x, y, h, n;
+	struct worm *w;
+	const struct options *op;
+	short *ip;
+	int CO, LI, last, bottom, ch, length, number, trail;
+	short **ref;
+	const char *field;
+	char *mp;
+	unsigned int delay = 0;
+
+	//	hb_init();
+	mp = NULL;
+	length = 16;
+	number = 3;
+	trail = ' ';
+	field = NULL;
+	while ((ch = getopt(argc, argv, "d:fl:n:t")) != -1)
+		switch(ch) {
+			case 'd':
+				if ((delay = (unsigned int)strtoul(optarg, (char **)NULL, 10)) < 1 || delay > 1000)
+					errx(1, "invalid delay (1-1000)");
+				delay *= 1000;  /* ms -> us */
+				break;
+			case 'f':
+				field = "WORM";
+				break;
+			case 'l':
+				if ((length = atoi(optarg)) < 2 || length > 1024) {
+					errx(1, "invalid length (%d - %d).",
+							2, 1024);
+				}
+				break;
+			case 'n':
+				if ((number = atoi(optarg)) < 1) {
+					errx(1, "invalid number of worms.");
+				}
+				break;
+			case 't':
+				trail = '.';
+				break;
+			case '?':
+			default:
+				(void)fprintf(stderr,
+					      "usage: worms [-ft] [-d delay] [-l length] [-n number]\n");
+				exit(1);
+		}
+
+	if (!(worm = malloc((size_t)number *
+					sizeof(struct worm))) || !(mp = malloc((size_t)1024)))
+		nomem();
+	initscr();
+	CO = COLS;
+	LI = LINES;
+	last = CO - 1;
+	bottom = LI - 1;
+	if (!(ip = malloc((size_t)(LI * CO * sizeof(short)))))
+		nomem();
+	if (!(ref = malloc((size_t)(LI * sizeof(short *)))))
+		nomem();
+	for (n = 0; n < LI; ++n) {
+		ref[n] = ip;
+		ip += CO;
+	}
+	for (ip = ref[0], n = LI * CO; --n >= 0;)
+		*ip++ = 0;
+	for (n = number, w = &worm[0]; --n >= 0; w++) {
+		w->orientation = w->head = 0;
+		if (!(ip = malloc((size_t)(length * sizeof(short)))))
+			nomem();
+		w->xpos = ip;
+		for (x = length; --x >= 0;)
+			*ip++ = -1;
+		if (!(ip = malloc((size_t)(length * sizeof(short)))))
+			nomem();
+		w->ypos = ip;
+		for (y = length; --y >= 0;)
+			*ip++ = -1;
+	}
+
+	(void)signal(SIGHUP, onsig);
+	(void)signal(SIGINT, onsig);
+	(void)signal(SIGQUIT, onsig);
+	(void)signal(SIGSTOP, onsig);
+	(void)signal(SIGTSTP, onsig);
+	(void)signal(SIGTERM, onsig);
+
+	if (field) {
+		const char *p = field;
+
+		for (y = LI; --y >= 0;) {
+			for (x = CO; --x >= 0;) {
+				addch(*p++);
+				if (!*p)
+					p = field;
+			}
+			refresh();
+		}
+	}
+	for (;;) {
+		refresh();
+		if (sig_caught) {
+			endwin();
+			exit(0);
+		}
+		for (n = 0, w = &worm[0]; n < number; n++, w++) {
+			if ((x = w->xpos[h = w->head]) < 0) {
+				mvaddch(y = w->ypos[h] = bottom,
+						x = w->xpos[h] = 0,
+						flavor[n % sizeof(flavor)]);
+				ref[y][x]++;
+			}
+			else
+				y = w->ypos[h];
+			if (++h == length)
+				h = 0;
+			if (w->xpos[w->head = h] >= 0) {
+				int x1, y1;
+
+				x1 = w->xpos[h];
+				y1 = w->ypos[h];
+				if (--ref[y1][x1] == 0) {
+					mvaddch(y1, x1, trail);
+				}
+			}
+			op = &(!x ? (!y ? upleft : (y == bottom ? lowleft : left)) : (x == last ? (!y ? upright : (y == bottom ? lowright : right)) : (!y ? upper : (y == bottom ? lower : normal))))[w->orientation];
+			switch (op->nopts) {
+				case 0:
+					refresh();
+					abort();
+					return(1);
+				case 1:
+					w->orientation = op->opts[0];
+					break;
+				default:
+					w->orientation =
+						op->opts[(int)random() % op->nopts];
+			}
+			mvaddch(y += yinc[w->orientation],
+					x += xinc[w->orientation],
+					flavor[n % sizeof(flavor)]);
+			ref[w->ypos[h] = y][w->xpos[h] = x]++;
+		}
+		if (usleep(delay))
+			onsig(SIGTERM);
+	}
+}
+
+	void
+onsig(int signo)
+{
+	sig_caught = 1;
+}
+
+	void
+nomem(void)
+{
+	errx(1, "not enough memory.");
+}

worms_mod.c

@@ -0,0 +1,347 @@
+/*
+ * Copyright (c) 1980, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static const char copyright[] =
+"@(#) Copyright (c) 1980, 1993\n\
+		The Regents of the University of California.  All rights reserved.\n";
+#endif /* not lint */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)worms.c	8.1 (Berkeley) 5/31/93";
+#endif
+static const char rcsid[] =
+"$FreeBSD: /repoman/r/ncvs/src/games/worms/worms.c,v 1.11 2002/02/23 10:35:25 billf Exp $";
+#endif /* not lint */
+
+/*
+ *
+ *	 @@@        @@@    @@@@@@@@@@     @@@@@@@@@@@    @@@@@@@@@@@@
+ *	 @@@        @@@   @@@@@@@@@@@@    @@@@@@@@@@@@   @@@@@@@@@@@@@
+ *	 @@@        @@@  @@@@      @@@@   @@@@           @@@@ @@@  @@@@
+ *	 @@@   @@   @@@  @@@        @@@   @@@            @@@  @@@   @@@
+ *	 @@@  @@@@  @@@  @@@        @@@   @@@            @@@  @@@   @@@
+ *	 @@@@ @@@@ @@@@  @@@        @@@   @@@            @@@  @@@   @@@
+ *	  @@@@@@@@@@@@   @@@@      @@@@   @@@            @@@  @@@   @@@
+ *	   @@@@  @@@@     @@@@@@@@@@@@    @@@            @@@  @@@   @@@
+ *	    @@    @@       @@@@@@@@@@     @@@            @@@  @@@   @@@
+ *
+ *				 Eric P. Scott
+ *			  Caltech High Energy Physics
+ *				 October, 1980
+ *
+ */
+#include <sys/types.h>
+#include <curses.h>
+#include <err.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static const struct options {
+	int nopts;
+	int opts[3];
+}
+normal[8] = {
+	{ 3, { 7, 0, 1 } },
+	{ 3, { 0, 1, 2 } },
+	{ 3, { 1, 2, 3 } },
+	{ 3, { 2, 3, 4 } },
+	{ 3, { 3, 4, 5 } },
+	{ 3, { 4, 5, 6 } },
+	{ 3, { 5, 6, 7 } },
+	{ 3, { 6, 7, 0 } }
+},	upper[8] = {
+	{ 1, { 1, 0, 0 } },
+	{ 2, { 1, 2, 0 } },
+	{ 0, { 0, 0, 0 } },
+	{ 0, { 0, 0, 0 } },
+	{ 0, { 0, 0, 0 } },
+	{ 2, { 4, 5, 0 } },
+	{ 1, { 5, 0, 0 } },
+	{ 2, { 1, 5, 0 } }
+},
+	left[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 2, { 2, 3, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 2, { 3, 7, 0 } },
+		{ 1, { 7, 0, 0 } },
+		{ 2, { 7, 0, 0 } }
+	},
+	right[8] = {
+		{ 1, { 7, 0, 0 } },
+		{ 2, { 3, 7, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 2, { 3, 4, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 2, { 6, 7, 0 } }
+	},
+	lower[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 2, { 0, 1, 0 } },
+		{ 1, { 1, 0, 0 } },
+		{ 2, { 1, 5, 0 } },
+		{ 1, { 5, 0, 0 } },
+		{ 2, { 5, 6, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } }
+	},
+	upleft[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 2, { 1, 3, 0 } },
+		{ 1, { 1, 0, 0 } }
+	},
+	upright[8] = {
+		{ 2, { 3, 5, 0 } },
+		{ 1, { 3, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 5, 0, 0 } }
+	},
+	lowleft[8] = {
+		{ 3, { 7, 0, 1 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 1, 0, 0 } },
+		{ 2, { 1, 7, 0 } },
+		{ 1, { 7, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } }
+	},
+	lowright[8] = {
+		{ 0, { 0, 0, 0 } },
+		{ 1, { 7, 0, 0 } },
+		{ 2, { 5, 7, 0 } },
+		{ 1, { 5, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } },
+		{ 0, { 0, 0, 0 } }
+	};
+
+
+static const char	flavor[] = {
+	'O', '*', '#', '$', '%', '0', '@', '~'
+};
+static const short	xinc[] = {
+	1,  1,  1,  0, -1, -1, -1,  0
+}, yinc[] = {
+	-1,  0,  1,  1,  1,  0, -1, -1
+};
+static struct	worm {
+	int orientation, head;
+	short *xpos, *ypos;
+} *worm;
+
+volatile sig_atomic_t sig_caught = 0;
+void	nomem(void);
+void	onsig(int);
+
+void detector_init();
+
+int main(int argc, char *argv[])
+{
+	detector_init();
+	int x, y, h, n;
+	struct worm *w;
+	const struct options *op;
+	short *ip;
+	int CO, LI, last, bottom, ch, length, number, trail;
+	short **ref;
+	const char *field;
+	char *mp;
+	unsigned int delay = 0;
+
+	//	hb_init();
+	mp = NULL;
+	length = 16;
+	number = 3;
+	trail = ' ';
+	field = NULL;
+	while ((ch = getopt(argc, argv, "d:fl:n:t")) != -1)
+		switch(ch) {
+			case 'd':
+				if ((delay = (unsigned int)strtoul(optarg, (char **)NULL, 10)) < 1 || delay > 1000)
+					errx(1, "invalid delay (1-1000)");
+				delay *= 1000;  /* ms -> us */
+				break;
+			case 'f':
+				field = "WORM";
+				break;
+			case 'l':
+				if ((length = atoi(optarg)) < 2 || length > 1024) {
+					errx(1, "invalid length (%d - %d).",
+							2, 1024);
+				}
+				break;
+			case 'n':
+				if ((number = atoi(optarg)) < 1) {
+					errx(1, "invalid number of worms.");
+				}
+				break;
+			case 't':
+				trail = '.';
+				break;
+			case '?':
+			default:
+				(void)fprintf(stderr,
+					      "usage: worms [-ft] [-d delay] [-l length] [-n number]\n");
+				exit(1);
+		}
+
+	if (!(worm = malloc((size_t)number *
+					sizeof(struct worm))) || !(mp = malloc((size_t)1024)))
+		nomem();
+	initscr();
+	CO = COLS;
+	LI = LINES;
+	last = CO - 1;
+	bottom = LI - 1;
+	if (!(ip = malloc((size_t)(LI * CO * sizeof(short)))))
+		nomem();
+	if (!(ref = malloc((size_t)(LI * sizeof(short *)))))
+		nomem();
+	for (n = 0; n < LI; ++n) {
+		ref[n] = ip;
+		ip += CO;
+	}
+	for (ip = ref[0], n = LI * CO; --n >= 0;)
+		*ip++ = 0;
+	for (n = number, w = &worm[0]; --n >= 0; w++) {
+		w->orientation = w->head = 0;
+		if (!(ip = malloc((size_t)(length * sizeof(short)))))
+			nomem();
+		w->xpos = ip;
+		for (x = length; --x >= 0;)
+			*ip++ = -1;
+		if (!(ip = malloc((size_t)(length * sizeof(short)))))
+			nomem();
+		w->ypos = ip;
+		for (y = length; --y >= 0;)
+			*ip++ = -1;
+	}
+
+	(void)signal(SIGHUP, onsig);
+	(void)signal(SIGINT, onsig);
+	(void)signal(SIGQUIT, onsig);
+	(void)signal(SIGSTOP, onsig);
+	(void)signal(SIGTSTP, onsig);
+	(void)signal(SIGTERM, onsig);
+
+	if (field) {
+		const char *p = field;
+
+		for (y = LI; --y >= 0;) {
+			for (x = CO; --x >= 0;) {
+				addch(*p++);
+				if (!*p)
+					p = field;
+			}
+			refresh();
+		}
+	}
+	for (;;) {
+		refresh();
+		if (sig_caught) {
+			endwin();
+			exit(0);
+		}
+		for (n = 0, w = &worm[0]; n < number; n++, w++) {
+			if ((x = w->xpos[h = w->head]) < 0) {
+				mvaddch(y = w->ypos[h] = bottom,
+						x = w->xpos[h] = 0,
+						flavor[n % sizeof(flavor)]);
+				ref[y][x]++;
+			}
+			else
+				y = w->ypos[h];
+			if (++h == length)
+				h = 0;
+			if (w->xpos[w->head = h] >= 0) {
+				int x1, y1;
+
+				x1 = w->xpos[h];
+				y1 = w->ypos[h];
+				if (--ref[y1][x1] == 0) {
+					mvaddch(y1, x1, trail);
+				}
+			}
+			op = &(!x ? (!y ? upleft : (y == bottom ? lowleft : left)) : (x == last ? (!y ? upright : (y == bottom ? lowright : right)) : (!y ? upper : (y == bottom ? lower : normal))))[w->orientation];
+			switch (op->nopts) {
+				case 0:
+					refresh();
+					abort();
+					return(1);
+				case 1:
+					w->orientation = op->opts[0];
+					break;
+				default:
+					w->orientation =
+						op->opts[(int)random() % op->nopts];
+			}
+			mvaddch(y += yinc[w->orientation],
+					x += xinc[w->orientation],
+					flavor[n % sizeof(flavor)]);
+			ref[w->ypos[h] = y][w->xpos[h] = x]++;
+		}
+		if (usleep(delay))
+			onsig(SIGTERM);
+	}
+}
+
+	void
+onsig(int signo)
+{
+	sig_caught = 1;
+}
+
+	void
+nomem(void)
+{
+	errx(1, "not enough memory.");
+}