server.c

早期freebsd实现

		mode &= ~04000;
	gid = -1;
	if (gr == NULL || strcmp(group, gr->gr_name) != 0) {
		if ((*group == ':' && (getgrgid(gid = atoi(group + 1)) == NULL))
		   || ((gr = getgrnam(group)) == NULL)) {
			if (mode & 02000) {
				note("%s:%s: unknown group", host, group);
				mode &= ~02000;
			}
		} else
			gid = gr->gr_gid;
	} else
		gid = gr->gr_gid;
	if (userid && gid >= 0) {
		if (gr) for (i = 0; gr->gr_mem[i] != NULL; i++)
			if (!(strcmp(user, gr->gr_mem[i])))
				goto ok;
		mode &= ~02000;
		gid = -1;
	}
ok:	if (fd != -1 && fchown(fd, uid, gid) < 0 || chown(file, uid, gid) < 0)
		note("%s: %s chown: %s", host, file, strerror(errno));
	else if (mode & 07000 &&
	   (fd != -1 && fchmod(fd, mode) < 0 || chmod(file, mode) < 0))
		note("%s: %s chmod: %s", host, file, strerror(errno));
	return(0);
}

/*
 * Check for files on the machine being updated that are not on the master
 * machine and remove them.
 */
static void
rmchk(opts)
	int opts;
{
	register char *cp, *s;
	struct stat stb;

	if (debug)
		printf("rmchk()\n");

	/*
	 * Tell the remote to clean the files from the last directory sent.
	 */
	(void) sprintf(buf, "C%o\n", opts & VERIFY);
	if (debug)
		printf("buf = %s", buf);
	(void) write(rem, buf, strlen(buf));
	if (response() < 0)
		return;
	for (;;) {
		cp = s = buf;
		do {
			if (read(rem, cp, 1) != 1)
				lostconn(0);
		} while (*cp++ != '\n' && cp < &buf[BUFSIZ]);

		switch (*s++) {
		case 'Q': /* Query if file should be removed */
			/*
			 * Return the following codes to remove query.
			 * N\n -- file exists - DON'T remove.
			 * Y\n -- file doesn't exist - REMOVE.
			 */
			*--cp = '\0';
			(void) sprintf(tp, "/%s", s);
			if (debug)
				printf("check %s\n", target);
			if (except(target))
				(void) write(rem, "N\n", 2);
			else if (lstat(target, &stb) < 0)
				(void) write(rem, "Y\n", 2);
			else
				(void) write(rem, "N\n", 2);
			break;

		case '\0':
			*--cp = '\0';
			if (*s != '\0')
				log(lfp, "%s\n", s);
			break;

		case 'E':
			*tp = '\0';
			ack();
			return;

		case '\1':
		case '\2':
			nerrs++;
			if (*s != '\n') {
				if (!iamremote) {
					fflush(stdout);
					(void) write(2, s, cp - s);
				}
				if (lfp != NULL)
					(void) fwrite(s, 1, cp - s, lfp);
			}
			if (buf[0] == '\2')
				lostconn(0);
			break;

		default:
			error("rmchk: unexpected response '%s'\n", buf);
			err();
		}
	}
}

/*
 * Check the current directory (initialized by the 'T' command to server())
 * for extraneous files and remove them.
 */
static void
clean(cp)
	register char *cp;
{
	DIR *d;
	register struct direct *dp;
	struct stat stb;
	char *otp;
	int len, opts;

	opts = 0;
	while (*cp >= '0' && *cp <= '7')
		opts = (opts << 3) | (*cp++ - '0');
	if (*cp != '\0') {
		error("clean: options not delimited\n");
		return;
	}
	if ((d = opendir(target)) == NULL) {
		error("%s:%s: %s\n", host, target, strerror(errno));
		return;
	}
	ack();

	otp = tp;
	len = tp - target;
	while (dp = readdir(d)) {
		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
			continue;
		if (len + 1 + strlen(dp->d_name) >= BUFSIZ - 1) {
			error("%s:%s/%s: Name too long\n",
				host, target, dp->d_name);
			continue;
		}
		tp = otp;
		*tp++ = '/';
		cp = dp->d_name;;
		while (*tp++ = *cp++)
			;
		tp--;
		if (lstat(target, &stb) < 0) {
			error("%s:%s: %s\n", host, target, strerror(errno));
			continue;
		}
		(void) sprintf(buf, "Q%s\n", dp->d_name);
		(void) write(rem, buf, strlen(buf));
		cp = buf;
		do {
			if (read(rem, cp, 1) != 1)
				cleanup(0);
		} while (*cp++ != '\n' && cp < &buf[BUFSIZ]);
		*--cp = '\0';
		cp = buf;
		if (*cp != 'Y')
			continue;
		if (opts & VERIFY) {
			cp = buf;
			*cp++ = '\0';
			(void) sprintf(cp, "need to remove: %s\n", target);
			(void) write(rem, buf, strlen(cp) + 1);
		} else
			removeit(&stb);
	}
	closedir(d);
	(void) write(rem, "E\n", 2);
	(void) response();
	tp = otp;
	*tp = '\0';
}

/*
 * Remove a file or directory (recursively) and send back an acknowledge
 * or an error message.
 */
static void
removeit(stp)
	struct stat *stp;
{
	DIR *d;
	struct direct *dp;
	register char *cp;
	struct stat stb;
	char *otp;
	int len;

	switch (stp->st_mode & S_IFMT) {
	case S_IFREG:
	case S_IFLNK:
		if (unlink(target) < 0)
			goto bad;
		goto removed;

	case S_IFDIR:
		break;

	default:
		error("%s:%s: not a plain file\n", host, target);
		return;
	}

	if ((d = opendir(target)) == NULL)
		goto bad;

	otp = tp;
	len = tp - target;
	while (dp = readdir(d)) {
		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
			continue;
		if (len + 1 + strlen(dp->d_name) >= BUFSIZ - 1) {
			error("%s:%s/%s: Name too long\n",
				host, target, dp->d_name);
			continue;
		}
		tp = otp;
		*tp++ = '/';
		cp = dp->d_name;;
		while (*tp++ = *cp++)
			;
		tp--;
		if (lstat(target, &stb) < 0) {
			error("%s:%s: %s\n", host, target, strerror(errno));
			continue;
		}
		removeit(&stb);
	}
	closedir(d);
	tp = otp;
	*tp = '\0';
	if (rmdir(target) < 0) {
bad:
		error("%s:%s: %s\n", host, target, strerror(errno));
		return;
	}
removed:
	cp = buf;
	*cp++ = '\0';
	(void) sprintf(cp, "removed %s\n", target);
	(void) write(rem, buf, strlen(cp) + 1);
}

/*
 * Execute a shell command to handle special cases.
 */
static void
dospecial(cmd)
	char *cmd;
{
	int fd[2], status, pid, i;
	register char *cp, *s;
	char sbuf[BUFSIZ];
	extern int userid, groupid;

	if (pipe(fd) < 0) {
		error("%s\n", strerror(errno));
		return;
	}
	if ((pid = fork()) == 0) {
		/*
		 * Return everything the shell commands print.
		 */
		(void) close(0);
		(void) close(1);
		(void) close(2);
		(void) open(_PATH_DEVNULL, O_RDONLY);
		(void) dup(fd[1]);
		(void) dup(fd[1]);
		(void) close(fd[0]);
		(void) close(fd[1]);
		setgid(groupid);
		setuid(userid);
		execl(_PATH_BSHELL, "sh", "-c", cmd, 0);
		_exit(127);
	}
	(void) close(fd[1]);
	s = sbuf;
	*s++ = '\0';
	while ((i = read(fd[0], buf, sizeof(buf))) > 0) {
		cp = buf;
		do {
			*s++ = *cp++;
			if (cp[-1] != '\n') {
				if (s < &sbuf[sizeof(sbuf)-1])
					continue;
				*s++ = '\n';
			}
			/*
			 * Throw away blank lines.
			 */
			if (s == &sbuf[2]) {
				s--;
				continue;
			}
			(void) write(rem, sbuf, s - sbuf);
			s = &sbuf[1];
		} while (--i);
	}
	if (s > &sbuf[1]) {
		*s++ = '\n';
		(void) write(rem, sbuf, s - sbuf);
	}
	while ((i = wait(&status)) != pid && i != -1)
		;
	if (i == -1)
		status = -1;
	(void) close(fd[0]);
	if (status)
		error("shell returned %d\n", status);
	else
		ack();
}

#if __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif

void
#if __STDC__
log(FILE *fp, const char *fmt, ...)
#else
log(fp, fmt, va_alist)
	FILE *fp;
	char *fmt;
        va_dcl
#endif
{
	va_list ap;
#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	/* Print changes locally if not quiet mode */
	if (!qflag)
		(void)vprintf(fmt, ap);

	/* Save changes (for mailing) if really updating files */
	if (!(options & VERIFY) && fp != NULL)
		(void)vfprintf(fp, fmt, ap);
	va_end(ap);
}

void
#if __STDC__
error(const char *fmt, ...)
#else
error(fmt, va_alist)
	char *fmt;
        va_dcl
#endif
{
	static FILE *fp;
	va_list ap;
#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif

	++nerrs;
	if (!fp && !(fp = fdopen(rem, "w")))
		return;
	if (iamremote) {
		(void)fprintf(fp, "%crdist: ", 0x01);
		(void)vfprintf(fp, fmt, ap);
		fflush(fp);
	}
	else {
		fflush(stdout);
		(void)fprintf(stderr, "rdist: ");
		(void)vfprintf(stderr, fmt, ap);
		fflush(stderr);
	}
	if (lfp != NULL) {
		(void)fprintf(lfp, "rdist: ");
		(void)vfprintf(lfp, fmt, ap);
		fflush(lfp);
	}
	va_end(ap);
}

void
#if __STDC__
fatal(const char *fmt, ...)
#else
fatal(fmt, va_alist)
	char *fmt;
        va_dcl
#endif
{
	static FILE *fp;
	va_list ap;
#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif

	++nerrs;
	if (!fp && !(fp = fdopen(rem, "w")))
		return;
	if (iamremote) {
		(void)fprintf(fp, "%crdist: ", 0x02);
		(void)vfprintf(fp, fmt, ap);
		fflush(fp);
	}
	else {
		fflush(stdout);
		(void)fprintf(stderr, "rdist: ");
		(void)vfprintf(stderr, fmt, ap);
		fflush(stderr);
	}
	if (lfp != NULL) {
		(void)fprintf(lfp, "rdist: ");
		(void)vfprintf(lfp, fmt, ap);
		fflush(lfp);
	}
	cleanup(0);
}

static int
response()
{
	char *cp, *s;
	char resp[BUFSIZ];

	if (debug)
		printf("response()\n");

	cp = s = resp;
	do {
		if (read(rem, cp, 1) != 1)
			lostconn(0);
	} while (*cp++ != '\n' && cp < &resp[BUFSIZ]);

	switch (*s++) {
	case '\0':
		*--cp = '\0';
		if (*s != '\0') {
			log(lfp, "%s\n", s);
			return(1);
		}
		return(0);
	case '\3':
		*--cp = '\0';
		log(lfp, "Note: %s\n",s);
		return(response());

	default:
		s--;
		/* fall into... */
	case '\1':
	case '\2':
		nerrs++;
		if (*s != '\n') {
			if (!iamremote) {
				fflush(stdout);
				(void) write(2, s, cp - s);
			}
			if (lfp != NULL)
				(void) fwrite(s, 1, cp - s, lfp);
		}
		if (resp[0] == '\2')
			lostconn(0);
		return(-1);
	}
}

/*
 * Remove temporary files and do any cleanup operations before exiting.
 */
void
cleanup(signo)
	int signo;
{
	(void) unlink(tempfile);
	exit(1);
}

static void
#if __STDC__
note(const char *fmt, ...)
#else
note(fmt, va_alist)
	char *fmt;
        va_dcl
#endif
{
	static char buf[BUFSIZ];
	va_list ap;
#if __STDC__
	va_start(ap, fmt);
#else
	va_start(ap);
#endif
	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
	va_end(ap);
	comment(buf);
}

static void
comment(s)
	char *s;
{
	char c;

	c = '\3';
	write(rem, &c, 1);
	write(rem, s, strlen(s));
	c = '\n';
	write(rem, &c, 1);
}