/*      $NetBSD: ls.c,v 1.79 2024/12/11 12:56:31 simonb Exp $   */

/*
 * Copyright (c) 1989, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Michael Fischbein.
 *
 * 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/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1989, 1993, 1994\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)ls.c        8.7 (Berkeley) 8/5/94";
#else
__RCSID("$NetBSD: ls.c,v 1.79 2024/12/11 12:56:31 simonb Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>

#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fts.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <termios.h>
#include <pwd.h>
#include <grp.h>
#include <util.h>

#include "ls.h"
#include "extern.h"

static void      display(FTSENT *, FTSENT *);
static int       mastercmp(const FTSENT **, const FTSENT **);
static void      traverse(int, char **, int);

static void (*printfcn)(DISPLAY *);
static int (*sortfcn)(const FTSENT *, const FTSENT *);

#define BY_NAME 0
#define BY_SIZE 1
#define BY_TIME 2

long blocksize;                 /* block size units */
int termwidth = 80;             /* default terminal width */
int sortkey = BY_NAME;
int rval = EXIT_SUCCESS;        /* exit value - set if error encountered */

/* flags */
int f_accesstime;               /* use time of last access */
int f_column;                   /* columnated format */
int f_columnacross;             /* columnated format, sorted across */
int f_flags;                    /* show flags associated with a file */
int f_grouponly;                /* long listing without owner */
int f_humanize;                 /* humanize the size field */
int f_commas;                   /* separate size field with comma */
int f_inode;                    /* print inode */
int f_listdir;                  /* list actual directory, not contents */
int f_listdot;                  /* list files beginning with . */
int f_longform;                 /* long listing format */
int f_nonprint;                 /* show unprintables as ? */
int f_nosort;                   /* don't sort output */
int f_numericonly;              /* don't convert uid/gid to name */
int f_octal;                    /* print octal escapes for nongraphic characters */
int f_octal_escape;             /* like f_octal but use C escapes if possible */
int f_recursive;                /* ls subdirectories also */
int f_reversesort;              /* reverse whatever sort is used */
int f_sectime;                  /* print the real time for all files */
int f_singlecol;                /* use single column output */
int f_size;                     /* list size in short listing */
int f_statustime;               /* use time of last mode change */
int f_stream;                   /* stream format */
int f_type;                     /* add type character for non-regular files */
int f_typedir;                  /* add type character for directories */
int f_whiteout;                 /* show whiteout entries */
int f_fullpath;                 /* print full pathname, not filename */
int f_leafonly;                 /* when recursing, print leaf names only */

__dead static void
usage(void)
{

        (void)fprintf(stderr,
            "usage: %s [-1AaBbCcdFfghikLlMmnOoPpqRrSsTtuWwXx] [file ...]\n",
            getprogname());
        exit(EXIT_FAILURE);
        /* NOTREACHED */
}

int
ls_main(int argc, char *argv[])
{
        static char dot[] = ".", *dotav[] = { dot, NULL };
        struct winsize win;
        int ch, fts_options;
        int kflag = 0;
        const char *p;

        setprogname(argv[0]);
        (void)setlocale(LC_ALL, "");

        /* Terminal defaults to -Cq, non-terminal defaults to -1. */
        if (isatty(STDOUT_FILENO)) {
                if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
                    win.ws_col > 0)
                        termwidth = win.ws_col;
                f_column = f_nonprint = 1;
        } else
                f_singlecol = 1;

        /* Root is -A automatically. */
        if (!getuid())
                f_listdot = 1;

        fts_options = FTS_PHYSICAL;
        while ((ch = getopt(argc, argv, "1AaBbCcdFfghikLlMmnOoPpqRrSsTtuWwXx"))
            != -1) {
                switch (ch) {
                /*
                 * The -1, -C, -l, -m and -x options all override each other so
                 * shell aliasing works correctly.
                 */
                case '1':
                        f_singlecol = 1;
                        f_column = f_columnacross = f_longform = f_stream = 0;
                        break;
                case 'C':
                        f_column = 1;
                        f_columnacross = f_longform = f_singlecol = f_stream =
                            0;
                        break;
                case 'g':
                        if (f_grouponly != -1)
                                f_grouponly = 1;
                        f_longform = 1;
                        f_column = f_columnacross = f_singlecol = f_stream = 0;
                        break;
                case 'l':
                        f_longform = 1;
                        f_column = f_columnacross = f_singlecol = f_stream = 0;
                        /* Never let -g take precedence over -l. */
                        f_grouponly = -1;
                        break;
                case 'm':
                        f_stream = 1;
                        f_column = f_columnacross = f_longform = f_singlecol =
                            0;
                        break;
                case 'x':
                        f_columnacross = 1;
                        f_column = f_longform = f_singlecol = f_stream = 0;
                        break;
                /* The -c and -u options override each other. */
                case 'c':
                        f_statustime = 1;
                        f_accesstime = 0;
                        break;
                case 'u':
                        f_accesstime = 1;
                        f_statustime = 0;
                        break;
                case 'F':
                        f_type = 1;
                        break;
                case 'L':
                        fts_options &= ~FTS_PHYSICAL;
                        fts_options |= FTS_LOGICAL;
                        break;
                case 'R':
                        f_recursive = 1;
                        break;
                case 'f':
                        f_nosort = 1;
                        /* FALLTHROUGH */
                case 'a':
                        fts_options |= FTS_SEEDOT;
                        /* FALLTHROUGH */
                case 'A':
                        f_listdot = 1;
                        break;
                /* The -B option turns off the -b, -q and -w options. */
                case 'B':
                        f_nonprint = 0;
                        f_octal = 1;
                        f_octal_escape = 0;
                        break;
                /* The -b option turns off the -B, -q and -w options. */
                case 'b':
                        f_nonprint = 0;
                        f_octal = 0;
                        f_octal_escape = 1;
                        break;
                /* The -d option turns off the -R option. */
                case 'd':
                        f_listdir = 1;
                        f_recursive = 0;
                        break;
                case 'i':
                        f_inode = 1;
                        break;
                case 'k':
                        blocksize = 1024;
                        kflag = 1;
                        f_humanize = 0;
                        break;
                /* The -h option forces all sizes to be measured in bytes. */
                case 'h':
                        f_humanize = 1;
                        kflag = 0;
                        f_commas = 0;
                        break;
                case 'M':
                        f_humanize = 0;
                        f_commas = 1;
                        break;
                case 'n':
                        f_numericonly = 1;
                        f_longform = 1;
                        f_column = f_columnacross = f_singlecol = f_stream = 0;
                        break;
                case 'O':
                        f_leafonly = 1;
                        break;
                case 'o':
                        f_flags = 1;
                        break;
                case 'P':
                        f_fullpath = 1;
                        break;
                case 'p':
                        f_typedir = 1;
                        break;
                /* The -q option turns off the -B, -b and -w options. */
                case 'q':
                        f_nonprint = 1;
                        f_octal = 0;
                        f_octal_escape = 0;
                        break;
                case 'r':
                        f_reversesort = 1;
                        break;
                case 'S':
                        sortkey = BY_SIZE;
                        break;
                case 's':
                        f_size = 1;
                        break;
                case 'T':
                        f_sectime = 1;
                        break;
                case 't':
                        sortkey = BY_TIME;
                        break;
                case 'W':
                        f_whiteout = 1;
                        break;
                /* The -w option turns off the -B, -b and -q options. */
                case 'w':
                        f_nonprint = 0;
                        f_octal = 0;
                        f_octal_escape = 0;
                        break;
                case 'X':
                        fts_options |= FTS_XDEV;
                        break;
                default:
                case '?':
                        usage();
                }
        }
        argc -= optind;
        argv += optind;

        if (f_column || f_columnacross || f_stream) {
                if ((p = getenv("COLUMNS")) != NULL)
                        termwidth = atoi(p);
        }

        /*
         * If both -g and -l options, let -l take precedence.
         */
        if (f_grouponly == -1)
                f_grouponly = 0;

        /*
         * If not -F, -i, -l, -p, -S, -s or -t options, don't require stat
         * information.
         */
        if (!f_inode && !f_longform && !f_size && !f_type && !f_typedir &&
            sortkey == BY_NAME)
                fts_options |= FTS_NOSTAT;

        /*
         * If not -F, -d or -l options, follow any symbolic links listed on
         * the command line.
         */
        if (!f_longform && !f_listdir && !f_type)
                fts_options |= FTS_COMFOLLOW;

        /*
         * If -W, show whiteout entries
         */
#ifdef FTS_WHITEOUT
        if (f_whiteout)
                fts_options |= FTS_WHITEOUT;
#endif

        /* If -i, -l, or -s, figure out block size. */
        if (f_inode || f_longform || f_size) {
                if (!kflag)
                        (void)getbsize(NULL, &blocksize);
                blocksize /= POSIX_BLOCK_SIZE;
        }

        /* Select a sort function. */
        if (f_reversesort) {
                switch (sortkey) {
                case BY_NAME:
                        sortfcn = revnamecmp;
                        break;
                case BY_SIZE:
                        sortfcn = revsizecmp;
                        break;
                case BY_TIME:
                        if (f_accesstime)
                                sortfcn = revacccmp;
                        else if (f_statustime)
                                sortfcn = revstatcmp;
                        else /* Use modification time. */
                                sortfcn = revmodcmp;
                        break;
                }
        } else {
                switch (sortkey) {
                case BY_NAME:
                        sortfcn = namecmp;
                        break;
                case BY_SIZE:
                        sortfcn = sizecmp;
                        break;
                case BY_TIME:
                        if (f_accesstime)
                                sortfcn = acccmp;
                        else if (f_statustime)
                                sortfcn = statcmp;
                        else /* Use modification time. */
                                sortfcn = modcmp;
                        break;
                }
        }

        /* Select a print function. */
        if (f_singlecol)
                printfcn = printscol;
        else if (f_columnacross)
                printfcn = printacol;
        else if (f_longform)
                printfcn = printlong;
        else if (f_stream)
                printfcn = printstream;
        else
                printfcn = printcol;

        if (argc)
                traverse(argc, argv, fts_options);
        else
                traverse(1, dotav, fts_options);
        return rval;
        /* NOTREACHED */
}

static int output;                      /* If anything output. */

/*
 * Traverse() walks the logical directory structure specified by the argv list
 * in the order specified by the mastercmp() comparison function.  During the
 * traversal it passes linked lists of structures to display() which represent
 * a superset (may be exact set) of the files to be displayed.
 */
static void
traverse(int argc, char *argv[], int options)
{
        FTS *ftsp;
        FTSENT *p, *chp;
        int ch_options, error;

        if ((ftsp =
            fts_open(argv, options, f_nosort ? NULL : mastercmp)) == NULL)
                err(EXIT_FAILURE, NULL);

        display(NULL, fts_children(ftsp, 0));
        if (f_listdir) {
                (void)fts_close(ftsp);
                return;
        }

        /*
         * If not recursing down this tree and don't need stat info, just get
         * the names.
         */
        ch_options = !f_recursive && options & FTS_NOSTAT ? FTS_NAMEONLY : 0;

        while ((p = fts_read(ftsp)) != NULL)
                switch (p->fts_info) {
                case FTS_DC:
                        warnx("%s: directory causes a cycle", p->fts_name);
                        break;
                case FTS_DNR:
                case FTS_ERR:
                        warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
                        rval = EXIT_FAILURE;
                        break;
                case FTS_D:
                        if (p->fts_level != FTS_ROOTLEVEL &&
                            p->fts_name[0] == '.' && !f_listdot) {
                                (void)fts_set(ftsp, p, FTS_SKIP);
                                break;
                        }

                        /*
                         * If already output something, put out a newline as
                         * a separator.  If multiple arguments, precede each
                         * directory with its name.
                         */
                        if (!f_leafonly) {
                                if (output)
                                        (void)printf("\n%s:\n", p->fts_path);
                                else if (argc > 1) {
                                        (void)printf("%s:\n", p->fts_path);
                                        output = 1;
                                }
                        }

                        chp = fts_children(ftsp, ch_options);
                        display(p, chp);

                        if (!f_recursive && chp != NULL)
                                (void)fts_set(ftsp, p, FTS_SKIP);
                        break;
                }
        error = errno;
        (void)fts_close(ftsp);
        errno = error;
        if (errno)
                err(EXIT_FAILURE, "fts_read");
}

/*
 * Display() takes a linked list of FTSENT structures and passes the list
 * along with any other necessary information to the print function.  P
 * points to the parent directory of the display list.
 */
static void
display(FTSENT *p, FTSENT *list)
{
        struct stat *sp;
        DISPLAY d;
        FTSENT *cur;
        NAMES *np;
        u_int64_t btotal;
        off_t maxsize;
        blkcnt_t maxblock;
        ino_t maxinode;
        int maxmajor, maxminor;
        uint32_t maxnlink;
        int bcfile, entries, flen, glen, ulen, maxflags, maxgroup;
        unsigned int maxlen;
        int maxuser, needstats;
        const char *user, *group;
        char buf[21];           /* 64 bits == 20 digits, +1 for NUL */
        char nuser[12], ngroup[12];
        char *flags = NULL;

        /*
         * If list is NULL there are two possibilities: that the parent
         * directory p has no children, or that fts_children() returned an
         * error.  We ignore the error case since it will be replicated
         * on the next call to fts_read() on the post-order visit to the
         * directory p, and will be signalled in traverse().
         */
        if (list == NULL)
                return;

        needstats = f_inode || f_longform || f_size;
        flen = 0;
        maxinode = maxnlink = 0;
        bcfile = 0;
        maxuser = maxgroup = maxflags = maxlen = 0;
        btotal = maxblock = maxsize = 0;
        maxmajor = maxminor = 0;
        for (cur = list, entries = 0; cur; cur = cur->fts_link) {
                if (cur->fts_info == FTS_ERR || cur->fts_info == FTS_NS) {
                        warnx("%s: %s",
                            cur->fts_name, strerror(cur->fts_errno));
                        cur->fts_number = NO_PRINT;
                        rval = EXIT_FAILURE;
                        continue;
                }

                /*
                 * P is NULL if list is the argv list, to which different rules
                 * apply.
                 */
                if (p == NULL) {
                        /* Directories will be displayed later. */
                        if (cur->fts_info == FTS_D && !f_listdir) {
                                cur->fts_number = NO_PRINT;
                                continue;
                        }
                } else {
                        /* Only display dot file if -a/-A set. */
                        if (cur->fts_name[0] == '.' && !f_listdot) {
                                cur->fts_number = NO_PRINT;
                                continue;
                        }
                }
                if (cur->fts_namelen > maxlen)
                        maxlen = cur->fts_namelen;
                if (needstats) {
                        sp = cur->fts_statp;
                        if (sp->st_blocks > maxblock)
                                maxblock = sp->st_blocks;
                        if (sp->st_ino > maxinode)
                                maxinode = sp->st_ino;
                        if (sp->st_nlink > maxnlink)
                                maxnlink = sp->st_nlink;
                        if (sp->st_size > maxsize)
                                maxsize = sp->st_size;
                        if (S_ISCHR(sp->st_mode) || S_ISBLK(sp->st_mode)) {
                                bcfile = 1;
                                if (major(sp->st_rdev) > maxmajor)
                                        maxmajor = major(sp->st_rdev);
                                if (minor(sp->st_rdev) > maxminor)
                                        maxminor = minor(sp->st_rdev);
                        }

                        btotal += sp->st_blocks;
                        if (f_longform) {
                                if (f_numericonly ||
                                    (user = user_from_uid(sp->st_uid, 0)) ==
                                    NULL) {
                                        (void)snprintf(nuser, sizeof(nuser),
                                            "%u", sp->st_uid);
                                        user = nuser;
                                }
                                if (f_numericonly ||
                                    (group = group_from_gid(sp->st_gid, 0)) ==
                                    NULL) {
                                        (void)snprintf(ngroup, sizeof(ngroup),
                                            "%u", sp->st_gid);
                                        group = ngroup;
                                }
                                if ((ulen = strlen(user)) > maxuser)
                                        maxuser = ulen;
                                if ((glen = strlen(group)) > maxgroup)
                                        maxgroup = glen;
                                if (f_flags) {
                                        flags =
                                            flags_to_string((u_long)sp->st_flags, "-");
                                        if ((flen = strlen(flags)) > maxflags)
                                                maxflags = flen;
                                } else
                                        flen = 0;

                                if ((np = malloc(sizeof(NAMES) +
                                    ulen + glen + flen + 2)) == NULL)
                                        err(EXIT_FAILURE, NULL);

                                np->user = &np->data[0];
                                (void)strcpy(np->user, user);
                                np->group = &np->data[ulen + 1];
                                (void)strcpy(np->group, group);

                                if (f_flags) {
                                        np->flags = &np->data[ulen + glen + 2];
                                        (void)strcpy(np->flags, flags);
                                        free(flags);
                                }
                                cur->fts_pointer = np;
                        }
                }
                ++entries;
        }

        if (!entries)
                return;

        d.list = list;
        d.entries = entries;
        d.maxlen = maxlen;
        if (needstats) {
                d.btotal = btotal;
                if (f_humanize) {
                        d.s_block = 4; /* min buf length for humanize_number */
                } else {
                        (void)snprintf(buf, sizeof(buf), "%lld",
                            (long long)howmany(maxblock, blocksize));
                        d.s_block = strlen(buf);
                        if (f_commas) /* allow for commas before every third digit */
                                d.s_block += (d.s_block - 1) / 3;
                }
                d.s_flags = maxflags;
                d.s_group = maxgroup;
                (void)snprintf(buf, sizeof(buf), "%llu",
                    (unsigned long long)maxinode);
                d.s_inode = strlen(buf);
                (void)snprintf(buf, sizeof(buf), "%u", maxnlink);
                d.s_nlink = strlen(buf);
                if (f_humanize) {
                        d.s_size = 4; /* min buf length for humanize_number */
                } else {
                        (void)snprintf(buf, sizeof(buf), "%lld",
                            (long long)maxsize);
                        d.s_size = strlen(buf);
                        if (f_commas) /* allow for commas before every third digit */
                                d.s_size += (d.s_size - 1) / 3;
                }
                d.s_user = maxuser;
                if (bcfile) {
                        (void)snprintf(buf, sizeof(buf), "%d", maxmajor);
                        d.s_major = strlen(buf);
                        (void)snprintf(buf, sizeof(buf), "%d", maxminor);
                        d.s_minor = strlen(buf);
                        if (d.s_major + d.s_minor + 2 > d.s_size)
                                d.s_size = d.s_major + d.s_minor + 2;
                        else if (d.s_size - d.s_minor - 2 > d.s_major)
                                d.s_major = d.s_size - d.s_minor - 2;
                } else {
                        d.s_major = 0;
                        d.s_minor = 0;
                }
        }

        printfcn(&d);
        output = 1;

        if (f_longform)
                for (cur = list; cur; cur = cur->fts_link)
                        free(cur->fts_pointer);
}

/*
 * Ordering for mastercmp:
 * If ordering the argv (fts_level = FTS_ROOTLEVEL) return non-directories
 * as larger than directories.  Within either group, use the sort function.
 * All other levels use the sort function.  Error entries remain unsorted.
 */
static int
mastercmp(const FTSENT **a, const FTSENT **b)
{
        int a_info, b_info;

        a_info = (*a)->fts_info;
        if (a_info == FTS_ERR)
                return (0);
        b_info = (*b)->fts_info;
        if (b_info == FTS_ERR)
                return (0);

        if (a_info == FTS_NS || b_info == FTS_NS) {
                if (b_info != FTS_NS)
                        return (1);
                else if (a_info != FTS_NS)
                        return (-1);
                else
                        return (namecmp(*a, *b));
        }

        if (a_info != b_info && !f_listdir &&
            (*a)->fts_level == FTS_ROOTLEVEL) {
                if (a_info == FTS_D)
                        return (1);
                else if (b_info == FTS_D)
                        return (-1);
        }
        return (sortfcn(*a, *b));
}