/*      $OpenBSD: utilities.c,v 1.55 2023/03/08 04:43:06 guenther Exp $ */
/*      $NetBSD: utilities.c,v 1.18 1996/09/27 22:45:20 christos Exp $  */

/*
 * Copyright (c) 1980, 1986, 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. 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.
 */

#include <sys/param.h>  /* DEV_BSIZE isset setbit clrbit */
#include <sys/time.h>
#include <sys/uio.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>
#include <ufs/ffs/fs.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <limits.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>

#include "fsutil.h"
#include "fsck.h"
#include "extern.h"

long                            diskreads, totalreads;  /* Disk cache statistics */
static struct bufarea           cgblk;                  /* backup buffer for cylinder group blocks */

static void rwerror(char *, daddr_t);

int
ftypeok(union dinode *dp)
{
        switch (DIP(dp, di_mode) & IFMT) {
        case IFDIR:
        case IFREG:
        case IFBLK:
        case IFCHR:
        case IFLNK:
        case IFSOCK:
        case IFIFO:
                return (1);
        default:
                if (debug)
                        printf("bad file type 0%o\n", DIP(dp, di_mode));
                return (0);
        }
}

int
reply(char *question)
{
        int persevere, c;

        if (preen)
                pfatal("INTERNAL ERROR: GOT TO reply()");
        persevere = !strcmp(question, "CONTINUE");
        printf("\n");
        if (!persevere && (nflag || fswritefd < 0)) {
                printf("%s? no\n\n", question);
                resolved = 0;
                return (0);
        }
        if (yflag || (persevere && nflag)) {
                printf("%s? yes\n\n", question);
                return (1);
        }

        do {
                printf("%s? [Fyn?] ", question);
                (void) fflush(stdout);
                c = getc(stdin);
                if (c == 'F') {
                        yflag = 1;
                        return (1);
                }
                while (c != '\n' && getc(stdin) != '\n') {
                        if (feof(stdin)) {
                                resolved = 0;
                                return (0);
                        }
                }
        } while (c != 'y' && c != 'Y' && c != 'n' && c != 'N');
        printf("\n");
        if (c == 'y' || c == 'Y')
                return (1);
        resolved = 0;
        return (0);
}

/*
 * Look up state information for an inode.
 */
struct inostat *
inoinfo(ino_t inum)
{
        static struct inostat unallocated = { USTATE, 0, 0 };
        struct inostatlist *ilp;
        int iloff;

        if (inum > maxino)
                errexit("inoinfo: inumber %llu out of range",
                    (unsigned long long)inum);
        ilp = &inostathead[inum / sblock.fs_ipg];
        iloff = inum % sblock.fs_ipg;
        if (iloff >= ilp->il_numalloced)
                return (&unallocated);
        return (&ilp->il_stat[iloff]);
}

/*
 * Malloc buffers and set up cache.
 */
void
bufinit(void)
{
        struct bufarea *bp;
        long bufcnt, i;
        char *bufp;

        pbp = pdirbp = NULL;
        bufp = malloc((unsigned int)sblock.fs_bsize);
        if (bufp == 0)
                errexit("cannot allocate buffer pool\n");
        cgblk.b_un.b_buf = bufp;
        initbarea(&cgblk);
        bufhead.b_next = bufhead.b_prev = &bufhead;
        bufcnt = MAXBUFSPACE / sblock.fs_bsize;
        if (bufcnt < MINBUFS)
                bufcnt = MINBUFS;
        for (i = 0; i < bufcnt; i++) {
                bp = malloc(sizeof(struct bufarea));
                bufp = malloc((unsigned int)sblock.fs_bsize);
                if (bp == NULL || bufp == NULL) {
                        free(bp);
                        free(bufp);
                        if (i >= MINBUFS)
                                break;
                        errexit("cannot allocate buffer pool\n");
                }
                bp->b_un.b_buf = bufp;
                bp->b_prev = &bufhead;
                bp->b_next = bufhead.b_next;
                bufhead.b_next->b_prev = bp;
                bufhead.b_next = bp;
                initbarea(bp);
        }
        bufhead.b_size = i;     /* save number of buffers */
}

/*
 * Manage cylinder group buffers.
 */
static struct bufarea *cgbufs;  /* header for cylinder group cache */
static int flushtries;          /* number of tries to reclaim memory */
struct bufarea *
cglookup(u_int cg)
{
        struct bufarea *cgbp;
        struct cg *cgp;

        if (cgbufs == NULL) {
                cgbufs = calloc(sblock.fs_ncg, sizeof(struct bufarea));
                if (cgbufs == NULL)
                        errexit("cannot allocate cylinder group buffers");
        }
        cgbp = &cgbufs[cg];
        if (cgbp->b_un.b_cg != NULL)
                return (cgbp);
        cgp = NULL;
        if (flushtries == 0)
                cgp = malloc((unsigned int)sblock.fs_cgsize);
        if (cgp == NULL) {
                getblk(&cgblk, cgtod(&sblock, cg), sblock.fs_cgsize);
                return (&cgblk);
        }
        cgbp->b_un.b_cg = cgp;
        initbarea(cgbp);
        getblk(cgbp, cgtod(&sblock, cg), sblock.fs_cgsize);
        return (cgbp);
}


/*
 * Manage a cache of directory blocks.
 */
struct bufarea *
getdatablk(daddr_t blkno, long size)
{
        struct bufarea *bp;

        for (bp = bufhead.b_next; bp != &bufhead; bp = bp->b_next)
                if (bp->b_bno == fsbtodb(&sblock, blkno))
                        goto foundit;
        for (bp = bufhead.b_prev; bp != &bufhead; bp = bp->b_prev)
                if ((bp->b_flags & B_INUSE) == 0)
                        break;
        if (bp == &bufhead)
                errexit("deadlocked buffer pool\n");
        getblk(bp, blkno, size);
        /* FALLTHROUGH */
foundit:
        totalreads++;
        bp->b_prev->b_next = bp->b_next;
        bp->b_next->b_prev = bp->b_prev;
        bp->b_prev = &bufhead;
        bp->b_next = bufhead.b_next;
        bufhead.b_next->b_prev = bp;
        bufhead.b_next = bp;
        bp->b_flags |= B_INUSE;
        return (bp);
}

void
getblk(struct bufarea *bp, daddr_t blk, long size)
{
        daddr_t dblk;

        dblk = fsbtodb(&sblock, blk);
        if (bp->b_bno != dblk) {
                flush(fswritefd, bp);
                diskreads++;
                bp->b_errs = bread(fsreadfd, bp->b_un.b_buf, dblk, size);
                bp->b_bno = dblk;
                bp->b_size = size;
        }
}

void
flush(int fd, struct bufarea *bp)
{
        int i, j;

        if (!bp->b_dirty)
                return;
        if (bp->b_errs != 0)
                pfatal("WRITING %sZERO'ED BLOCK %lld TO DISK\n",
                    (bp->b_errs == bp->b_size / DEV_BSIZE) ? "" : "PARTIALLY ",
                    (long long)bp->b_bno);
        bp->b_dirty = 0;
        bp->b_errs = 0;
        bwrite(fd, bp->b_un.b_buf, bp->b_bno, (long)bp->b_size);
        if (bp != &sblk)
                return;
        for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
                bwrite(fswritefd, (char *)sblock.fs_csp + i,
                    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
                    sblock.fs_cssize - i < sblock.fs_bsize ?
                    sblock.fs_cssize - i : sblock.fs_bsize);
        }
}

static void
rwerror(char *mesg, daddr_t blk)
{

        if (preen == 0)
                printf("\n");
        pfatal("CANNOT %s: BLK %lld", mesg, (long long)blk);
        if (reply("CONTINUE") == 0)
                errexit("Program terminated\n");
}

void
ckfini(int markclean)
{
        struct bufarea *bp, *nbp;
        int cnt = 0;
        sigset_t oset, nset;
        int64_t sblockloc;

        sigemptyset(&nset);
        sigaddset(&nset, SIGINT);
        sigprocmask(SIG_BLOCK, &nset, &oset);

        if (fswritefd < 0) {
                (void)close(fsreadfd);
                fsreadfd = -1;
                sigprocmask(SIG_SETMASK, &oset, NULL);
                return;
        }
        if (sblock.fs_magic == FS_UFS1_MAGIC) {
                sblockloc = SBLOCK_UFS1;
                sblock.fs_ffs1_time = sblock.fs_time;
                sblock.fs_ffs1_size = sblock.fs_size;
                sblock.fs_ffs1_dsize = sblock.fs_dsize;
                sblock.fs_ffs1_csaddr = sblock.fs_csaddr;
                sblock.fs_ffs1_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
                sblock.fs_ffs1_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
                sblock.fs_ffs1_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
                sblock.fs_ffs1_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
                /* Force update on next mount */
                sblock.fs_ffs1_flags &= ~FS_FLAGS_UPDATED;
        } else
                sblockloc = SBLOCK_UFS2;
        flush(fswritefd, &sblk);
        if (havesb && sblk.b_bno != sblockloc / DEV_BSIZE && !preen &&
            reply("UPDATE STANDARD SUPERBLOCK")) {
                sblk.b_bno = sblockloc / DEV_BSIZE;
                sbdirty();
                flush(fswritefd, &sblk);
        }
        flush(fswritefd, &cgblk);
        free(cgblk.b_un.b_buf);
        for (bp = bufhead.b_prev; bp && bp != &bufhead; bp = nbp) {
                cnt++;
                flush(fswritefd, bp);
                nbp = bp->b_prev;
                free(bp->b_un.b_buf);
                free(bp);
        }
        if (bufhead.b_size != cnt)
                errexit("Panic: lost %d buffers\n", bufhead.b_size - cnt);
        if (cgbufs != NULL) {   
                for (cnt = 0; cnt < sblock.fs_ncg; cnt++) {
                        if (cgbufs[cnt].b_un.b_cg == NULL)
                                continue;
                        flush(fswritefd, &cgbufs[cnt]);
                        free(cgbufs[cnt].b_un.b_cg);
                }
                free(cgbufs);
        }
        pbp = pdirbp = NULL;
        if (markclean && (sblock.fs_clean & FS_ISCLEAN) == 0) {
                /*
                 * Mark the file system as clean, and sync the superblock.
                 */
                if (preen)
                        pwarn("MARKING FILE SYSTEM CLEAN\n");
                else if (!reply("MARK FILE SYSTEM CLEAN"))
                        markclean = 0;
                if (markclean) {
                        sblock.fs_clean = FS_ISCLEAN;
                        sbdirty();
                        flush(fswritefd, &sblk);
                }
        }
        if (debug)
                printf("cache missed %ld of %ld (%d%%)\n", diskreads,
                    totalreads, (int)(diskreads * 100 / totalreads));
        (void)close(fsreadfd);
        fsreadfd = -1;
        (void)close(fswritefd);
        fswritefd = -1;
        sigprocmask(SIG_SETMASK, &oset, NULL);
}

int
bread(int fd, char *buf, daddr_t blk, long size)
{
        char *cp;
        int i, errs;
        off_t offset;

        offset = blk;
        offset *= DEV_BSIZE;
        if (pread(fd, buf, size, offset) == size)
                return (0);
        rwerror("READ", blk);
        errs = 0;
        memset(buf, 0, (size_t)size);
        printf("THE FOLLOWING DISK SECTORS COULD NOT BE READ:");
        for (cp = buf, i = 0; i < size; i += secsize, cp += secsize) {
                if (pread(fd, cp, secsize, offset + i) != secsize) {
                        if (secsize != DEV_BSIZE)
                                printf(" %lld (%lld),",
                                    (long long)(offset + i) / secsize,
                                    (long long)blk + i / DEV_BSIZE);
                        else
                                printf(" %lld,", (long long)blk +
                                    i / DEV_BSIZE);
                        errs++;
                }
        }
        printf("\n");
        return (errs);
}

void
bwrite(int fd, char *buf, daddr_t blk, long size)
{
        int i;
        char *cp;
        off_t offset;

        if (fd < 0)
                return;
        offset = blk;
        offset *= DEV_BSIZE;
        if (pwrite(fd, buf, size, offset) == size) {
                fsmodified = 1;
                return;
        }
        rwerror("WRITE", blk);
        printf("THE FOLLOWING SECTORS COULD NOT BE WRITTEN:");
        for (cp = buf, i = 0; i < size; i += secsize, cp += secsize)
                if (pwrite(fd, cp, secsize, offset + i) != secsize) {
                        if (secsize != DEV_BSIZE)
                                printf(" %lld (%lld),",
                                    (long long)(offset + i) / secsize,
                                    (long long)blk + i / DEV_BSIZE);
                        else
                                printf(" %lld,", (long long)blk +
                                    i / DEV_BSIZE);
                }
        printf("\n");
        return;
}

/*
 * allocate a data block with the specified number of fragments
 */
daddr_t
allocblk(int frags)
{
        daddr_t i, baseblk;
        int j, k, cg;
        struct bufarea *cgbp;
        struct cg *cgp;

        if (frags <= 0 || frags > sblock.fs_frag)
                return (0);
        for (i = 0; i < maxfsblock - sblock.fs_frag; i += sblock.fs_frag) {
                for (j = 0; j <= sblock.fs_frag - frags; j++) {
                        if (testbmap(i + j))
                                continue;
                        for (k = 1; k < frags; k++)
                                if (testbmap(i + j + k))
                                        break;
                        if (k < frags) {
                                j += k;
                                continue;
                        }
                        cg = dtog(&sblock, i + j);
                        cgbp = cglookup(cg);
                        cgp = cgbp->b_un.b_cg;
                        if (!cg_chkmagic(cgp))
                                pfatal("CG %d: BAD MAGIC NUMBER\n", cg);
                        baseblk = dtogd(&sblock, i + j);

                        for (k = 0; k < frags; k++) {
                                setbmap(i + j + k);
                                clrbit(cg_blksfree(cgp), baseblk + k);
                        }
                        n_blks += frags;
                        if (frags == sblock.fs_frag)
                                cgp->cg_cs.cs_nbfree--;
                        else
                                cgp->cg_cs.cs_nffree -= frags;
                        return (i + j);
                }
        }
        return (0);
}

/*
 * Free a previously allocated block
 */
void
freeblk(daddr_t blkno, int frags)
{
        struct inodesc idesc;

        idesc.id_blkno = blkno;
        idesc.id_numfrags = frags;
        (void)pass4check(&idesc);
}

/*
 * Find a pathname
 */
void
getpathname(char *namebuf, size_t namebuflen, ino_t curdir, ino_t ino)
{
        int len;
        char *cp;
        struct inodesc idesc;
        static int busy = 0;

        if (curdir == ino && ino == ROOTINO) {
                (void)strlcpy(namebuf, "/", namebuflen);
                return;
        }
        if (busy ||
            (GET_ISTATE(curdir) != DSTATE && GET_ISTATE(curdir) != DFOUND)) {
                (void)strlcpy(namebuf, "?", namebuflen);
                return;
        }
        busy = 1;
        memset(&idesc, 0, sizeof(struct inodesc));
        idesc.id_type = DATA;
        idesc.id_fix = IGNORE;
        cp = &namebuf[PATH_MAX - 1];
        *cp = '\0';
        if (curdir != ino) {
                idesc.id_parent = curdir;
                goto namelookup;
        }
        while (ino != ROOTINO) {
                idesc.id_number = ino;
                idesc.id_func = findino;
                idesc.id_name = "..";
                if ((ckinode(ginode(ino), &idesc) & FOUND) == 0)
                        break;
        namelookup:
                idesc.id_number = idesc.id_parent;
                idesc.id_parent = ino;
                idesc.id_func = findname;
                idesc.id_name = namebuf;
                if ((ckinode(ginode(idesc.id_number), &idesc)&FOUND) == 0)
                        break;
                len = strlen(namebuf);
                cp -= len;
                memmove(cp, namebuf, (size_t)len);
                *--cp = '/';
                if (cp < &namebuf[MAXNAMLEN])
                        break;
                ino = idesc.id_number;
        }
        busy = 0;
        if (ino != ROOTINO)
                *--cp = '?';
        memmove(namebuf, cp, (size_t)(&namebuf[PATH_MAX] - cp));
}

void
catch(int signo)
{
        ckfini(0);                      /* XXX signal race */
        _exit(12);
}

/*
 * When preening, allow a single quit to signal
 * a special exit after filesystem checks complete
 * so that reboot sequence may be interrupted.
 */
void
catchquit(int signo)
{
        extern volatile sig_atomic_t returntosingle;
        static const char message[] =
            "returning to single-user after filesystem check\n";

        write(STDOUT_FILENO, message, sizeof(message)-1);
        returntosingle = 1;
        (void)signal(SIGQUIT, SIG_DFL);
}

/*
 * Ignore a single quit signal; wait and flush just in case.
 * Used by child processes in preen.
 */
void
voidquit(int signo)
{
        int save_errno = errno;

        sleep(1);
        (void)signal(SIGQUIT, SIG_IGN);
        (void)signal(SIGQUIT, SIG_DFL);
        errno = save_errno;
}

/*
 * determine whether an inode should be fixed.
 */
int
dofix(struct inodesc *idesc, char *msg)
{
        switch (idesc->id_fix) {

        case DONTKNOW:
                if (idesc->id_type == DATA)
                        direrror(idesc->id_number, msg);
                else
                        pwarn("%s", msg);
                if (preen) {
                        printf(" (SALVAGED)\n");
                        idesc->id_fix = FIX;
                        return (ALTERED);
                }
                if (reply("SALVAGE") == 0) {
                        idesc->id_fix = NOFIX;
                        return (0);
                }
                idesc->id_fix = FIX;
                return (ALTERED);

        case FIX:
                return (ALTERED);

        case NOFIX:
        case IGNORE:
                return (0);

        default:
                errexit("UNKNOWN INODESC FIX MODE %u\n", idesc->id_fix);
        }
        /* NOTREACHED */
}

int (* info_fn)(char *, size_t) = NULL;
char *info_filesys = "?";

void
catchinfo(int signo)
{
        static int info_fd;
        int save_errno = errno;
        struct iovec iov[4];
        char buf[1024];

        if (signo == 0) {
                info_fd = open(_PATH_TTY, O_WRONLY);
                signal(SIGINFO, catchinfo);
        } else if (info_fd > 0 && info_fn != NULL && info_fn(buf, sizeof buf)) {
                iov[0].iov_base = info_filesys;
                iov[0].iov_len = strlen(info_filesys);
                iov[1].iov_base = ": ";
                iov[1].iov_len = sizeof ": " - 1;
                iov[2].iov_base = buf;
                iov[2].iov_len = strlen(buf);
                iov[3].iov_base = "\n";
                iov[3].iov_len = sizeof "\n" - 1;

                writev(info_fd, iov, 4);
        }
        errno = save_errno;
}
/*
 * Attempt to flush a cylinder group cache entry.
 * Return whether the flush was successful.
 */
static int
flushentry(void)
{
        struct bufarea *cgbp;

        if (flushtries == sblock.fs_ncg || cgbufs == NULL)
                return (0);
        cgbp = &cgbufs[flushtries++];
        if (cgbp->b_un.b_cg == NULL)
                return (0);
        flush(fswritefd, cgbp);
        free(cgbp->b_un.b_buf);
        cgbp->b_un.b_buf = NULL;
        return (1);
}

/*
 * Wrapper for malloc() that flushes the cylinder group cache to try
 * to get space.
 */
void *
Malloc(size_t size)
{
        void *retval;

        while ((retval = malloc(size)) == NULL)
                if (flushentry() == 0)
                        break;
        return (retval);
}

/*
 * Wrapper for calloc() that flushes the cylinder group cache to try
 * to get space.
 */
void*
Calloc(size_t cnt, size_t size)
{
        void *retval;

        while ((retval = calloc(cnt, size)) == NULL)
                if (flushentry() == 0)
                        break;
        return (retval);
}

/*
 * Wrapper for reallocarray() that flushes the cylinder group cache to try
 * to get space.
 */
void*
Reallocarray(void *p, size_t cnt, size_t size)
{
        void *retval;

        while ((retval = reallocarray(p, cnt, size)) == NULL)
                if (flushentry() == 0)
                        break;
        return (retval);
}