/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (C) 1991, 1994 Wolfgang Solfrank.
 * Copyright (C) 1991, 1994 TooLs GmbH.
 * 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 TooLs GmbH.
 * 4. The name of TooLs GmbH may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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>
#include <sys/mount.h>
#include <sys/disklabel.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <fstab.h>
#include <inttypes.h>
#include <libufs.h>
#include <mntopts.h>
#include <paths.h>
#include <pwd.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

/* some flags of what to do: */
static bool all;
static bool count;
static bool noname;
static bool unused;
static void (*func)(int, struct fs *);
static long blocksize;
static char *header;
static int headerlen;

static union dinode *get_inode(int, struct fs *, ino_t);
static int      isfree(struct fs *, union dinode *);
static void     inituser(void);
static void     usrrehash(void);
static struct user *user(uid_t);
static int      cmpusers(const void *, const void *);
static void     uses(uid_t, daddr_t, time_t);
static void     initfsizes(void);
static void     dofsizes(int, struct fs *);
static void     douser(int, struct fs *);
static void     donames(int, struct fs *);
static void     usage(void);
static void     quot(char *, char *);

/*
 * Original BSD quot doesn't round to number of frags/blocks,
 * doesn't account for indirection blocks and gets it totally
 * wrong if the size is a multiple of the blocksize.
 * The new code always counts the number of 512 byte blocks
 * instead of the number of kilobytes and converts them to
 * kByte when done (on request).
 *
 * Due to the size of modern disks, we must cast intermediate
 * values to 64 bits to prevent potential overflows.
 */
#define SIZE(n) ((int)(((intmax_t)(n) * 512 + blocksize - 1) / blocksize))

#define INOCNT(fs)      ((fs)->fs_ipg)
#define INOSZ(fs) \
        (((fs)->fs_magic == FS_UFS1_MAGIC ? sizeof(struct ufs1_dinode) : \
        sizeof(struct ufs2_dinode)) * INOCNT(fs))

#define DIP(fs, dp, field) \
        (((fs)->fs_magic == FS_UFS1_MAGIC) ? \
        (dp)->dp1.field : (dp)->dp2.field)

static union dinode *
get_inode(int fd, struct fs *super, ino_t ino)
{
        static union dinode *ipbuf;
        static struct cg *cgp;
        static ino_t last;
        static unsigned long cg;
        struct ufs2_dinode *di2;
        off_t off;

        if (fd < 0) {           /* flush cache */
                free(ipbuf);
                ipbuf = NULL;
                free(cgp);
                cgp = NULL;
                return (NULL);
        }

        if (ipbuf == NULL || ino < last || ino >= last + INOCNT(super)) {
                if (super->fs_magic == FS_UFS2_MAGIC &&
                    (cgp == NULL || cg != ino_to_cg(super, ino))) {
                        cg = ino_to_cg(super, ino);
                        if (cgp == NULL && (cgp = malloc(super->fs_cgsize)) == NULL)
                                errx(1, "allocate cg");
                        if (lseek(fd, (off_t)cgtod(super, cg) << super->fs_fshift, 0) < 0)
                                err(1, "lseek cg");
                        if (read(fd, cgp, super->fs_cgsize) != super->fs_cgsize)
                                err(1, "read cg");
                        if (!cg_chkmagic(cgp))
                                errx(1, "cg has bad magic");
                }
                if (ipbuf == NULL && (ipbuf = malloc(INOSZ(super))) == NULL)
                        errx(1, "allocate inodes");
                last = rounddown(ino, INOCNT(super));
                off = (off_t)ino_to_fsba(super, last) << super->fs_fshift;
                if (lseek(fd, off, SEEK_SET) != off ||
                    read(fd, ipbuf, INOSZ(super)) != (ssize_t)INOSZ(super))
                        err(1, "read inodes");
        }

        if (super->fs_magic == FS_UFS1_MAGIC)
                return ((union dinode *)
                    &((struct ufs1_dinode *)ipbuf)[ino % INOCNT(super)]);
        di2 = &((struct ufs2_dinode *)ipbuf)[ino % INOCNT(super)];
        /* If the inode is unused, it might be unallocated too, so zero it. */
        if (isclr(cg_inosused(cgp), ino % super->fs_ipg))
                memset(di2, 0, sizeof(*di2));
        return ((union dinode *)di2);
}

static int
isfree(struct fs *super, union dinode *dp)
{
        switch (DIP(super, dp, di_mode) & IFMT) {
        case IFIFO:
        case IFLNK:             /* should check FASTSYMLINK? */
        case IFDIR:
        case IFREG:
                return 0;
        case IFCHR:
        case IFBLK:
        case IFSOCK:
        case IFWHT:
        case 0:
                return 1;
        default:
                errx(1, "unknown IFMT 0%o", DIP(super, dp, di_mode) & IFMT);
        }
}

static struct user {
        uid_t uid;
        char *name;
        daddr_t space;
        long count;
        daddr_t spc30;
        daddr_t spc60;
        daddr_t spc90;
} *users;
static unsigned int nusers;

static void
inituser(void)
{
        struct user *usr;
        unsigned int i;

        if (nusers == 0) {
                nusers = 8;
                if ((users = calloc(nusers, sizeof(*users))) == NULL)
                        errx(1, "allocate users");
        } else {
                for (usr = users, i = nusers; i-- > 0; usr++) {
                        usr->space = usr->spc30 = usr->spc60 = usr->spc90 = 0;
                        usr->count = 0;
                }
        }
}

static void
usrrehash(void)
{
        struct user *usr, *usrn;
        struct user *svusr;
        unsigned int i;

        svusr = users;
        nusers *= 2;
        if ((users = calloc(nusers, sizeof(*users))) == NULL)
                errx(1, "allocate users");
        for (usr = svusr, i = nusers / 2; i-- > 0; usr++) {
                for (usrn = users + usr->uid % nusers; usrn->name; usrn--) {
                        if (usrn <= users)
                                usrn += nusers;
                }
                *usrn = *usr;
        }
}

static struct user *
user(uid_t uid)
{
        struct user *usr;
        struct passwd *pwd;
        unsigned int i;

        while (1) {
                for (usr = users + uid % nusers, i = nusers; i-- > 0; usr--) {
                        if (usr->name == NULL) {
                                usr->uid = uid;
                                if (noname || (pwd = getpwuid(uid)) == NULL)
                                        asprintf(&usr->name, "#%u", uid);
                                else
                                        usr->name = strdup(pwd->pw_name);
                                if (usr->name == NULL)
                                        errx(1, "allocate users");
                        }
                        if (usr->uid == uid)
                                return (usr);
                        if (usr <= users)
                                usr += nusers;
                }
                usrrehash();
        }
}

static int
cmpusers(const void *v1, const void *v2)
{
        const struct user *u1 = v1, *u2 = v2;

        return (u2->space > u1->space ? 1 :
            u2->space < u1->space ? -1 :
            u1->uid > u2->uid ? 1 :
            u1->uid < u2->uid ? -1 : 0);
}

#define sortusers(users)                                                \
        qsort((users), nusers, sizeof(struct user), cmpusers)

static void
uses(uid_t uid, daddr_t blks, time_t act)
{
        static time_t today;
        struct user *usr;

        if (!today)
                time(&today);

        usr = user(uid);
        usr->count++;
        usr->space += blks;

        if (today - act > 90L * 24L * 60L * 60L)
                usr->spc90 += blks;
        if (today - act > 60L * 24L * 60L * 60L)
                usr->spc60 += blks;
        if (today - act > 30L * 24L * 60L * 60L)
                usr->spc30 += blks;
}

#define FSZCNT  512U
static struct fsizes {
        struct fsizes *fsz_next;
        daddr_t fsz_first, fsz_last;
        ino_t fsz_count[FSZCNT];
        daddr_t fsz_sz[FSZCNT];
} *fsizes;

static void
initfsizes(void)
{
        struct fsizes *fp;
        unsigned int i;

        for (fp = fsizes; fp; fp = fp->fsz_next) {
                for (i = FSZCNT; i-- > 0;) {
                        fp->fsz_count[i] = 0;
                        fp->fsz_sz[i] = 0;
                }
        }
}

static void
dofsizes(int fd, struct fs *super)
{
        ino_t inode, maxino;
        union dinode *dp;
        daddr_t sz, ksz;
        struct fsizes *fp, **fsp;
        unsigned int i;

        maxino = super->fs_ncg * super->fs_ipg - 1;
        for (inode = 0; inode < maxino; inode++) {
                if ((dp = get_inode(fd, super, inode)) != NULL &&
                    !isfree(super, dp)) {
                        sz = DIP(super, dp, di_blocks);
                        ksz = SIZE(sz);
                        for (fsp = &fsizes; (fp = *fsp); fsp = &fp->fsz_next) {
                                if (ksz < fp->fsz_last)
                                        break;
                        }
                        if (fp == NULL || ksz < fp->fsz_first) {
                                if ((fp = malloc(sizeof(*fp))) == NULL)
                                        errx(1, "allocate fsize structure");
                                fp->fsz_next = *fsp;
                                *fsp = fp;
                                fp->fsz_first = rounddown(ksz, FSZCNT);
                                fp->fsz_last = fp->fsz_first + FSZCNT;
                                for (i = FSZCNT; i-- > 0;) {
                                        fp->fsz_count[i] = 0;
                                        fp->fsz_sz[i] = 0;
                                }
                        }
                        fp->fsz_count[ksz % FSZCNT]++;
                        fp->fsz_sz[ksz % FSZCNT] += sz;
                }
        }
        sz = 0;
        for (fp = fsizes; fp != NULL; fp = fp->fsz_next) {
                for (i = 0; i < FSZCNT; i++) {
                        if (fp->fsz_count[i] != 0) {
                                printf("%jd\t%jd\t%d\n",
                                    (intmax_t)(fp->fsz_first + i),
                                    (intmax_t)fp->fsz_count[i],
                                    SIZE(sz += fp->fsz_sz[i]));
                        }
                }
        }
}

static void
douser(int fd, struct fs *super)
{
        ino_t inode, maxino;
        struct user *usr, *usrs;
        union dinode *dp;
        int n;

        maxino = super->fs_ncg * super->fs_ipg - 1;
        for (inode = 0; inode < maxino; inode++) {
                if ((dp = get_inode(fd, super, inode)) != NULL &&
                    !isfree(super, dp)) {
                        uses(DIP(super, dp, di_uid),
                            DIP(super, dp, di_blocks),
                            DIP(super, dp, di_atime));
                }
        }
        if ((usrs = malloc(nusers * sizeof(*usrs))) == NULL)
                errx(1, "allocate users");
        memcpy(usrs, users, nusers * sizeof(*usrs));
        sortusers(usrs);
        for (usr = usrs, n = nusers; --n >= 0 && usr->count; usr++) {
                printf("%5d", SIZE(usr->space));
                if (count)
                        printf("\t%5ld", usr->count);
                printf("\t%-8s", usr->name);
                if (unused) {
                        printf("\t%5d\t%5d\t%5d",
                            SIZE(usr->spc30),
                            SIZE(usr->spc60),
                            SIZE(usr->spc90));
                }
                printf("\n");
        }
        free(usrs);
}

static void
donames(int fd, struct fs *super)
{
        union dinode *dp;
        char *end, *line;
        size_t cap;
        ssize_t len;
        intmax_t inode, maxino;

        maxino = super->fs_ncg * super->fs_ipg - 1;
        line = NULL;
        cap = 0;
        while ((len = getline(&line, &cap, stdin)) > 0) {
                if (len > 0 && line[len - 1] == '\n')
                        line[--len] = '\0';
                inode = strtoimax(line, &end, 10);
                /*
                 * Silently ignore lines that do not begin with a number.
                 * For backward compatibility reasons, we do not require
                 * the optional comment to be preceded by whitespace.
                 */
                if (end == line)
                        continue;
                if (inode <= 0 || inode > maxino) {
                        warnx("invalid inode %jd", inode);
                        continue;
                }
                if ((dp = get_inode(fd, super, inode)) != NULL &&
                    !isfree(super, dp)) {
                        printf("%s\t", user(DIP(super, dp, di_uid))->name);
                        /* now skip whitespace */
                        while (*end == ' ' || *end == '\t')
                                end++;
                        /* and print out the remainder of the input line */
                        printf("%s\n", end);
                } else {
                        /* skip this line */
                }
        }
        free(line);
}

static void
usage(void)
{
        fprintf(stderr, "usage: quot [-cfknv] [-a | filesystem ...]\n");
        exit(1);
}

void
quot(char *name, char *mp)
{
        int fd;
        struct fs *fs;

        get_inode(-1, NULL, 0);         /* flush cache */
        inituser();
        initfsizes();
        if ((fd = open(name, 0)) < 0) {
                warn("%s", name);
                close(fd);
                return;
        }
        switch (errno = sbget(fd, &fs, UFS_STDSB, UFS_NOCSUM)) {
        case 0:
                break;
        case ENOENT:
                warn("Cannot find file system superblock");
                close(fd);
                return;
        default:
                warn("Unable to read file system superblock");
                close(fd);
                return;
        }
        printf("%s:", name);
        if (mp)
                printf(" (%s)", mp);
        putchar('\n');
        (*func)(fd, fs);
        free(fs);
        close(fd);
}

int
main(int argc, char *argv[])
{
        struct statfs *mp;
        int ch, cnt;

        func = douser;
        header = getbsize(&headerlen, &blocksize);
        while ((ch = getopt(argc, argv, "acfhkNnv")) != -1) {
                switch (ch) {
                case 'a':
                        all = true;
                        break;
                case 'c':
                        func = dofsizes;
                        break;
                case 'f':
                        count = true;
                        break;
                case 'h':
                        /* ignored for backward compatibility */
                        break;
                case 'k':
                        blocksize = 1024;
                        break;
                case 'N':
                        noname = true;
                        break;
                case 'n':
                        func = donames;
                        break;
                case 'v':
                        unused = true;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;

        if ((argc == 0 && !all) || (all && argc))
                usage();

        if (all) {
                for (cnt = getmntinfo(&mp, MNT_NOWAIT); --cnt >= 0; mp++)
                        if (strncmp(mp->f_fstypename, "ufs", MFSNAMELEN) == 0)
                                quot(mp->f_mntfromname, mp->f_mntonname);
        }
        while (argc-- > 0) {
                if ((mp = getmntpoint(*argv)) != NULL)
                        quot(mp->f_mntfromname, mp->f_mntonname);
                else
                        quot(*argv, 0);
                argv++;
        }
        return (0);
}