recreate root directory if missing or trashed

[unix-history] / usr / src / sbin / fsck / main.c

#ifndef lint
static char version[] = "@(#)main.c	3.3 (Berkeley) %G%";
#endif

#include <sys/param.h>
#include <sys/inode.h>
#include <sys/fs.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fstab.h>
#include <strings.h>
#include "fsck.h"

char	*rawname(), *unrawname(), *blockcheck();
int	catch();
int	(*signal())();

main(argc, argv)
	int	argc;
	char	*argv[];
{
	struct fstab *fsp;
	int pid, passno, anygtr, sumstatus;
	char *name;

	sync();
	while (--argc > 0 && **++argv == '-') {
		switch (*++*argv) {

		case 'p':
			preen++;
			break;

		case 'b':
			if (argv[0][1] != '\0') {
				bflag = atoi(argv[0]+1);
			} else {
				bflag = atoi(*++argv);
				argc--;
			}
			printf("Alternate super block location: %d\n", bflag);
			break;

		case 'd':
			debug++;
			break;

		case 'n':	/* default no answer flag */
		case 'N':
			nflag++;
			yflag = 0;
			break;

		case 'y':	/* default yes answer flag */
		case 'Y':
			yflag++;
			nflag = 0;
			break;

		default:
			errexit("%c option?\n", **argv);
		}
	}
	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
		(void)signal(SIGINT, catch);
	if (argc) {
		while (argc-- > 0) {
			hotroot = 0;
			checkfilesys(*argv++);
		}
		exit(0);
	}
	sumstatus = 0;
	passno = 1;
	do {
		anygtr = 0;
		if (setfsent() == 0)
			errexit("Can't open checklist file: %s\n", FSTAB);
		while ((fsp = getfsent()) != 0) {
			if (strcmp(fsp->fs_type, FSTAB_RW) &&
			    strcmp(fsp->fs_type, FSTAB_RO) &&
			    strcmp(fsp->fs_type, FSTAB_RQ))
				continue;
			if (preen == 0 ||
			    passno == 1 && fsp->fs_passno == passno) {
				name = blockcheck(fsp->fs_spec);
				if (name != NULL)
					checkfilesys(name);
				else if (preen)
					exit(8);
			} else if (fsp->fs_passno > passno) {
				anygtr = 1;
			} else if (fsp->fs_passno == passno) {
				pid = fork();
				if (pid < 0) {
					perror("fork");
					exit(8);
				}
				if (pid == 0) {
					name = blockcheck(fsp->fs_spec);
					if (name == NULL)
						exit(8);
					checkfilesys(name);
					exit(0);
				}
			}
		}
		if (preen) {
			union wait status;
			while (wait(&status) != -1)
				sumstatus |= status.w_retcode;
		}
		passno++;
	} while (anygtr);
	if (sumstatus)
		exit(8);
	(void)endfsent();
	exit(0);
}

checkfilesys(filesys)
	char *filesys;
{
	daddr_t n_ffree, n_bfree;

	devname = filesys;
	if (setup(filesys) == 0) {
		if (preen)
			pfatal("CAN'T CHECK FILE SYSTEM.");
		return;
	}
	/*
	 * 1: scan inodes tallying blocks used
	 */
	if (preen == 0) {
		printf("** Last Mounted on %s\n", sblock.fs_fsmnt);
		if (hotroot)
			printf("** Root file system\n");
		printf("** Phase 1 - Check Blocks and Sizes\n");
	}
	pass1();

	/*
	 * 1b: locate first references to duplicates, if any
	 */
	if (enddup != &duplist[0]) {
		if (preen)
			pfatal("INTERNAL ERROR: dups with -p");
		printf("** Phase 1b - Rescan For More DUPS\n");
		pass1b();
	}

	/*
	 * 2: traverse directories from root to mark all connected directories
	 */
	if (preen == 0)
		printf("** Phase 2 - Check Pathnames\n");
	pass2();

	/*
	 * 3: scan inodes looking for disconnected directories
	 */
	if (preen == 0)
		printf("** Phase 3 - Check Connectivity\n");
	pass3();

	/*
	 * 4: scan inodes looking for disconnected files; check reference counts
	 */
	if (preen == 0)
		printf("** Phase 4 - Check Reference Counts\n");
	pass4();

	/*
	 * 5: check and repair resource counts in cylinder groups
	 */
	if (preen == 0)
		printf("** Phase 5 - Check Cyl groups\n");
	pass5();

	/*
	 * print out summary statistics
	 */
	n_ffree = sblock.fs_cstotal.cs_nffree;
	n_bfree = sblock.fs_cstotal.cs_nbfree;
	pwarn("%d files, %d used, %d free (%d frags, %d blocks)\n", n_files,
	    n_blks, n_ffree + sblock.fs_frag * n_bfree, n_ffree, n_bfree);
	if (debug && (n_files -= imax - ROOTINO - sblock.fs_cstotal.cs_nifree))
		printf("%d files missing\n", n_files);
	if (debug) {
		n_blks += sblock.fs_ncg *
			(cgdmin(&sblock, 0) - cgsblock(&sblock, 0));
		n_blks += cgsblock(&sblock, 0) - cgbase(&sblock, 0);
		n_blks += howmany(sblock.fs_cssize, sblock.fs_fsize);
		if (n_blks -= fmax - (n_ffree + sblock.fs_frag * n_bfree))
			printf("%d blocks missing\n", n_blks);
	}
	if (dfile.mod) {
		(void)time(&sblock.fs_time);
		sbdirty();
	}
	ckfini();
	free(blockmap);
	free(statemap);
	free((char *)lncntp);
	if (!dfile.mod)
		return;
	if (!preen) {
		printf("\n***** FILE SYSTEM WAS MODIFIED *****\n");
		if (hotroot)
			printf("\n***** REBOOT UNIX *****\n");
	}
	if (hotroot) {
		sync();
		exit(4);
	}
}

char *
blockcheck(name)
	char *name;
{
	struct stat stslash, stblock, stchar;
	char *raw;
	int looped = 0;

	hotroot = 0;
	if (stat("/", &stslash) < 0){
		printf("Can't stat root\n");
		return (0);
	}
retry:
	if (stat(name, &stblock) < 0){
		printf("Can't stat %s\n", name);
		return (0);
	}
	if (stblock.st_mode & S_IFBLK) {
		raw = rawname(name);
		if (stat(raw, &stchar) < 0){
			printf("Can't stat %s\n", raw);
			return (0);
		}
		if (stchar.st_mode & S_IFCHR) {
			if (stslash.st_dev == stblock.st_rdev) {
				hotroot++;
				raw = unrawname(name);
			}
			return (raw);
		} else {
			printf("%s is not a character device\n", raw);
			return (0);
		}
	} else if (stblock.st_mode & S_IFCHR) {
		if (looped) {
			printf("Can't make sense out of name %s\n", name);
			return (0);
		}
		name = unrawname(name);
		looped++;
		goto retry;
	}
	printf("Can't make sense out of name %s\n", name);
	return (0);
}

char *
unrawname(cp)
	char *cp;
{
	char *dp = rindex(cp, '/');
	struct stat stb;

	if (dp == 0)
		return (cp);
	if (stat(cp, &stb) < 0)
		return (cp);
	if ((stb.st_mode&S_IFMT) != S_IFCHR)
		return (cp);
	if (*(dp+1) != 'r')
		return (cp);
	(void)strcpy(dp+1, dp+2);
	return (cp);
}

char *
rawname(cp)
	char *cp;
{
	static char rawbuf[32];
	char *dp = rindex(cp, '/');

	if (dp == 0)
		return (0);
	*dp = 0;
	(void)strcpy(rawbuf, cp);
	*dp = '/';
	(void)strcat(rawbuf, "/r");
	(void)strcat(rawbuf, dp+1);
	return (rawbuf);
}