adv.c

操作系统SunOS 4.1.3版本的源码

	if ((clist = (char **)malloc(NUM_MACHS * sizeof(char *))) == NULL) {
		fprintf(stderr,"%s: cannot allocate memory for client list\n",cmd);
		exit(1);
	}

	/*
	 *	If the alias table exists, replace names defined 
	 *	as aliases, or else assume the names to be
	 *	valid client names and form a client list.
	 */

	while ((clname = clients[index]) != NULL) {
		if (*clname == '\0' || verify(clname)) {
			clients[index++][0] = '\0';
			continue;
		}

		if (aflag && isalias(clname,altptr)) {
			old_pos = pos;
			search_atbl(clname,aliases);
			if (old_pos == pos)
				clients[index][0] = '\0';
		} else {
			if (!invalid(clname) && !in_clist(clname))
				add_client(clname);
			else
				clients[index][0] = '\0';
		}
		index++;
	}

	if (pos == (low_index + NUM_MACHS))
		alloc_mem();
	clist[pos] = NULL;
}

static
isalias(name,altbl)
char	*name;
struct	altab	*altbl;
{

	register int i;

	for (i = 0; i < aliases; i++) {
		if (strcmp(name,altbl->alname) == SAME)
			return(1);
		altbl++;
	}
	return(0);
}

static
search_atbl(name,index)
char	*name;
int	index;
{

	register int i, level;
	register char *list, *curr_pos;
	char	*realloc();
	char	buffer[SZ_CLIENT + 1];
	struct	altab	*altbl;

	/*
	 *	Search the alias table to determine if "name" is an
	 *	alias. If it is an alias obtain its corresponding
	 *	list of names, and determine if they are aliases by
	 *	searching preceding entries in the alias table. This
	 *	is done to eliminate loops. When "name" is no longer
	 * 	an alias copy it into the client list.		
	 */

	altbl = altptr;
	level = 0;
	for (i = 0; i < index; i++) {
		if (strcmp(name,altbl->alname) == SAME) {
			list = altbl->alist;
			curr_pos = strpbrk(list," \t");
			while (curr_pos != NULL) {
				if (curr_pos-list <= SZ_CLIENT) {
					strncpy(buffer,list,curr_pos-list);
					buffer[curr_pos-list] = '\0';
					search_atbl(buffer,level);
				} else {
					*curr_pos = '\0';
					fprintf(stderr,"%s: client/alias name <%s> exceeds <%d> characters, ignored\n",cmd,list,SZ_CLIENT);
					*curr_pos = ' ';
				}
				list = curr_pos + strspn(curr_pos," \t");
				curr_pos = strpbrk(list," \t");
			}
			if (*list == '\0')
				return;

			if (strlen(list) <= SZ_CLIENT) {
				strcpy(buffer,list);
				search_atbl(buffer,level);
			} else
				fprintf(stderr,"%s: client/alias name <%s> exceeds <%d> characters, ignored\n",cmd,list,SZ_CLIENT);
			return;
		} else {
			level++;
			altbl++;
		}
	}
	if (!invalid(name) && !in_clist(name))
		add_client(name);
	return;
}

static
in_clist(name)
char	*name;
{

 	register int i;

	for (i = 0; i < pos; i++) {
		if (strcmp(name,clist[i]) == SAME)
			return(1);
	}
	return(0);
}

static
add_client(name)
char	*name;
{

	if (pos == (low_index + NUM_MACHS))
		alloc_mem();
	if ((clist[pos] = malloc((unsigned)strlen(name)+1)) == NULL ) {
		fprintf(stderr,"%s: cannot allocate memory for client list\n",cmd);
		exit(1);
	}
	strcpy(clist[pos++],name);
}

static
verify(name)
char	*name;
{

	register char *chr;

	if (strlen(name) > SZ_CLIENT) {
		fprintf(stderr,"%s: client/alias name <%s> exceeds <%d> characters, ignored\n",cmd,name,SZ_CLIENT);
		return(1);
	}

	chr = name;
	while (*chr != '\0') {
		if (!isprint(*chr)) {
			fprintf(stderr,"%s: client/alias name <%s> contains non-printable characters, ignored\n",cmd,name);
			return(1);
		}
		chr++;
	}
	return(0);
}

static
alloc_mem()
{

	char   *realloc();

	if ((clist = (char **)realloc((char *)clist,(NUM_MACHS + pos) * sizeof (char *))) == NULL) {
		fprintf(stderr,"%s: cannot allocate memory for client list\n",cmd);
		exit(1);
	}
	low_index = pos;
}

static
invalid(name)
char	*name;
{

	char	*mach;
	char	*domain;
	int	qname = 0, dname = 0;

	if (name[strlen(name)-1] == SEPARATOR)
		dname = 1;

	if (*(domain = dompart(name)) != '\0') {
		qname = 1;
		if (strlen(domain) > SZ_DELEMENT) {
			fprintf(stderr,"%s: domain name %s<%s> exceeds <%d> characters, ignored\n",cmd,dname ? "":"in ",name,SZ_DELEMENT);
			return(1);
		}

		if (v_dname(domain) != 0) {
			fprintf(stderr,"%s: domain name %s<%s> contains invalid characters, ignored\n",cmd,dname ? "":"in ",name);
			return(1);
		}
	}

	if (*(mach = namepart(name)) != '\0') {
		if (strlen(mach) > SZ_MACH) {
			fprintf(stderr,"%s: nodename %s<%s> exceeds <%d> characters, ignored\n",cmd,qname ? "in ":"",name,SZ_MACH);
			return(1);
		}

		if (v_uname(mach) != 0) {
			fprintf(stderr,"%s: nodename %s<%s> contains invalid characters, ignored\n",cmd,qname ? "in ":"",name);
			return(1);
		}
	}
	return(0);
}

static
update_entry(res,path,desc,rflag,clients)
short	rflag;
char	*res, *path, *desc;
char	*clients[];
{

	register FILE  *fp, *fp1;
	int	index = 0;
	char	advbuf[BUFSIZE], buf[BUFSIZE];

	if ((fp = fopen(ADVFILE, "r")) == NULL) {
		add_entry(res,path,desc,rflag,clients);
		return;
	}

	/*	
	 *	Update the client and/or description
	 *	fields of an existing entry.
	 */

	stat(ADVFILE,&stbuf);
	if ((fp1 = fopen(TEMPADV, "w")) == NULL) {
		fprintf(stderr,"%s: cannot create temporary advertise file <%s>\n",cmd,TEMPADV);
		exit(1);
	}

	while (fgets(advbuf,BUFSIZE,fp)) {
		get_data(advbuf);
		if (strcmp(res,fieldv[0]) == SAME) {
			fprintf(fp1,"%s  %s",res,fieldv[1]);
			if (dflag)
				fprintf(fp1,"  \"%s\"",desc);
			fprintf(fp1,"  %s ",fieldv[2]);
			strncpy(buf, fieldv[3], strlen(fieldv[3])-1);
                        strcpy(fieldv[3], buf);
			fprintf(fp1,"  %s ",fieldv[3]);

			if (clients[index] == NULL)
				fprintf(fp1," %s",fieldv[4]);
			else {
				while (clients[index] != NULL) {
					if (clients[index][0] != '\0')
						fprintf(fp1," %s",clients[index]);
					index++;
				}	
				fprintf(fp1,"\n");
			}
		} else 
			fprintf(fp1,"%s  %s  %s  %s  %s",fieldv[0],fieldv[1],fieldv[2],fieldv[3],fieldv[4]);
	}
	fclose(fp);
	fclose(fp1);
	unlink(ADVFILE);
	link(TEMPADV,ADVFILE);
	chmod(ADVFILE,MASK);
	chown(ADVFILE,(int)stbuf.st_uid,(int)stbuf.st_gid);
	unlink(TEMPADV);
}

static
add_entry(res,path,desc,rflag,clients)
short	rflag;
char	*res, *path, *desc;
char	*clients[];
{

	register FILE	*fp;
	char	*comment = "unrestricted";
	int	index = 0;


	if ((fp = fopen(ADVFILE, "a")) == NULL) {
		fprintf(stderr,"%s: cannot open <%s>\n",cmd,ADVFILE);
		exit(1);
	}
	fprintf(fp,"%s  %s  \"%s\"  %s",res,path,desc,flg[rflag]);

	if (clients[index] == NULL)
		fprintf(fp," %s",comment);
	else {
		while (clients[index] != NULL) {
			if (clients[index][0] != '\0')
				fprintf(fp," %s",clients[index]);
			index++;
		}
	}
	fprintf(fp,"\n");
	fclose(fp);
}

static
get_data(s)
char	*s;
{

	register int fieldc = 0;

	/*
 	 *	This function parses an advertise entry from 
 	 *	/etc/advtab and sets the pointers appropriately.
 	 */

	while ((*s != '\n') && (*s != '\0') && (fieldc < 4)) {
		while (isspace(*s))
			s++;
		fieldv[fieldc++] = s;
		if (fieldc == 3) {
		/*
		 *	Now obtain the description associated with
	 	 *	the resource.
		 */
			s = strpbrk(s + 1,"\"");
			*(++s) = '\0';
			s++;
			while (isspace(*s))
				s++;
			fieldv[fieldc] = s;
			break;
		}
		while (!isspace(*s))
			s++;
		*(s++) = '\0';
	}
}

static
ns_adv(req_type,path,res,desc,roflg,namelist)
short	req_type, roflg;
char	*path, *res, *desc;
char	**namelist;
{

	struct	nssend	send;
	struct	nssend	*ns_getblock();

	/*	
	 *	Initialize structure with information to be sent
	 *	to the name server.
	 */

	send.ns_code = req_type;
	send.ns_type = 1;
	send.ns_flag = roflg;
	send.ns_name = res;
	send.ns_path = path;
	send.ns_desc = desc;
	send.ns_mach = namelist;

	/*
	 *	Send the structure using the name server function
	 *	ns_getblock().
	 */

	if (ns_getblock(&send) == NULL)
		return(RFS_FAILURE);

	return(RFS_SUCCESS);
} 

static
rpterr(res,dir)
char	*res;
char	*dir;
{

	switch(errno) {
	case EPERM:
		fprintf(stderr,"%s: must be super-user\n",cmd);
		break;
	case ENOENT:
		fprintf(stderr,"%s: <%s> no such file or directory\n",cmd,dir);
		break;
	case ENONET:
		fprintf(stderr,"%s: machine not on the network\n",cmd);
		break;
	case ENOTDIR:
		fprintf(stderr,"%s: <%s> not a directory\n",cmd,dir);
		break;
	case EREMOTE:
		fprintf(stderr,"%s: <%s> is remote\n",cmd,dir);
		break;
	case EADV:
		fprintf(stderr,"%s: <%s> already advertised\n",cmd,dir);
		break;
	case EROFS:
		fprintf(stderr,"%s: <%s> write-protected\n",cmd,dir);
		break;
	case EINTR:
		fprintf(stderr,"%s: system call interrupted\n",cmd);
		break;
	case EBUSY:
		fprintf(stderr,"%s: resource <%s> currently advertises a different directory\n",cmd,res);
		break;
	case EEXIST:
		fprintf(stderr,"%s: re-advertise error: <%s> was originally advertised under\n     a different resource name\n",cmd,dir);
		break;
	case ENOSPC:
		fprintf(stderr,"%s: advertise table overflow\n",cmd);
		break;
	case EINVAL:
		fprintf(stderr,"%s: invalid resource name\n",cmd);
		break;
	case EFAULT:
		fprintf(stderr,"%s: bad user address\n",cmd);
		break;
	case ENOMEM:
		fprintf(stderr,"%s: not enough memory\n",cmd);
		break;
	case ENODEV:
		fprintf(stderr,"%s: <%s> not advertised\n",cmd,res);
		break;
	case ESRMNT:
		fprintf(stderr,"%s: re-advertise error: a client that is not in the specified\n     client list currently has <%s> mounted\n",cmd,res);
		break;
	case EACCES:
		fprintf(stderr,"%s: re-advertise error: resource <%s> originally advertised\n     with different permissions\n",cmd,res);
		break;
	default:
		fprintf(stderr,"%s: errno <%d>, cannot advertise <%s>\n",cmd,errno,res);
		break;
	}
}