/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * 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/param.h>
#include <sys/stat.h>
#include <sys/acl.h>

#include <err.h>
#include <errno.h>
#include <fts.h>
#include <langinfo.h>
#include <libutil.h>
#include <limits.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <wchar.h>
#ifdef COLORLS
#include <ctype.h>
#include <termcap.h>
#include <signal.h>
#endif

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

static int      printaname(const FTSENT *, u_long, u_long);
static void     printdev(size_t, dev_t);
static void     printlink(const FTSENT *);
static void     printtime(time_t);
static int      printtype(u_int);
static void     printsize(size_t, off_t);
#ifdef COLORLS
static void     endcolor_termcap(int);
static void     endcolor_ansi(void);
static void     endcolor(int);
static int      colortype(mode_t);
#endif
static void     aclmode(char *, const FTSENT *);

#define IS_NOPRINT(p)   ((p)->fts_number == NO_PRINT)

#ifdef COLORLS
/* Most of these are taken from <sys/stat.h> */
typedef enum Colors {
        C_DIR,                  /* directory */
        C_LNK,                  /* symbolic link */
        C_SOCK,                 /* socket */
        C_FIFO,                 /* pipe */
        C_EXEC,                 /* executable */
        C_BLK,                  /* block special */
        C_CHR,                  /* character special */
        C_SUID,                 /* setuid executable */
        C_SGID,                 /* setgid executable */
        C_WSDIR,                /* directory writeble to others, with sticky
                                 * bit */
        C_WDIR,                 /* directory writeble to others, without
                                 * sticky bit */
        C_NUMCOLORS             /* just a place-holder */
} Colors;

static const char *defcolors = "exfxcxdxbxegedabagacad";

/* colors for file types */
static struct {
        int     num[2];
        bool    bold;
        bool    underline;
} colors[C_NUMCOLORS];
#endif

static size_t padding_for_month[12];
static size_t month_max_size = 0;

void
printscol(const DISPLAY *dp)
{
        FTSENT *p;

        for (p = dp->list; p; p = p->fts_link) {
                if (IS_NOPRINT(p))
                        continue;
                (void)printaname(p, dp->s_inode, dp->s_block);
                (void)putchar('\n');
        }
}

/*
 * print name in current style
 */
int
printname(const char *name)
{
        if (f_octal || f_octal_escape)
                return prn_octal(name);
        else if (f_nonprint)
                return prn_printable(name);
        else
                return prn_normal(name);
}

static const char *
get_abmon(int mon)
{

        switch (mon) {
        case 0: return (nl_langinfo(ABMON_1));
        case 1: return (nl_langinfo(ABMON_2));
        case 2: return (nl_langinfo(ABMON_3));
        case 3: return (nl_langinfo(ABMON_4));
        case 4: return (nl_langinfo(ABMON_5));
        case 5: return (nl_langinfo(ABMON_6));
        case 6: return (nl_langinfo(ABMON_7));
        case 7: return (nl_langinfo(ABMON_8));
        case 8: return (nl_langinfo(ABMON_9));
        case 9: return (nl_langinfo(ABMON_10));
        case 10: return (nl_langinfo(ABMON_11));
        case 11: return (nl_langinfo(ABMON_12));
        }

        /* should never happen */
        abort();
}

static size_t
mbswidth(const char *month)
{
        wchar_t wc;
        size_t width, donelen, clen, w;

        width = donelen = 0;
        while ((clen = mbrtowc(&wc, month + donelen, MB_LEN_MAX, NULL)) != 0) {
                if (clen == (size_t)-1 || clen == (size_t)-2)
                        return (-1);
                donelen += clen;
                if ((w = wcwidth(wc)) == (size_t)-1)
                        return (-1);
                width += w;
        }

        return (width);
}

static void
compute_abbreviated_month_size(void)
{
        int i;
        size_t width;
        size_t months_width[12];

        for (i = 0; i < 12; i++) {
                width = mbswidth(get_abmon(i));
                if (width == (size_t)-1) {
                        month_max_size = -1;
                        return;
                }
                months_width[i] = width;
                if (width > month_max_size)
                        month_max_size = width;
        }

        for (i = 0; i < 12; i++)
                padding_for_month[i] = month_max_size - months_width[i];
}

void
printlong(const DISPLAY *dp)
{
        struct stat *sp;
        FTSENT *p;
        NAMES *np;
        char buf[20];
#ifdef COLORLS
        int color_printed = 0;
#endif

        if ((dp->list == NULL || dp->list->fts_level != FTS_ROOTLEVEL) &&
            (f_longform || f_size)) {
                if (!f_humanval)
                        (void)printf("total %lu\n", howmany(dp->btotal, blocksize));
                else {
                        (void)humanize_number(buf, 7 /* "1024 KB" */,
                            dp->btotal * 512, "B", HN_AUTOSCALE, HN_DECIMAL);

                        (void)printf("total %s\n", buf);
                }
        }

        for (p = dp->list; p; p = p->fts_link) {
                if (IS_NOPRINT(p))
                        continue;
                sp = p->fts_statp;
                if (f_inode)
                        (void)printf("%*ju ",
                            dp->s_inode, (uintmax_t)sp->st_ino);
                if (f_size)
                        (void)printf(f_thousands ? "%'*jd " : "%*jd ",
                            dp->s_block, howmany(sp->st_blocks, blocksize));
                strmode(sp->st_mode, buf);
                aclmode(buf, p);
                np = p->fts_pointer;
                (void)printf("%s %*ju ", buf, dp->s_nlink,
                    (uintmax_t)sp->st_nlink);
                if (!f_sowner)
                        (void)printf("%-*s ", dp->s_user, np->user);
                (void)printf("%-*s ", dp->s_group, np->group);
                if (f_flags)
                        (void)printf("%-*s ", dp->s_flags, np->flags);
                if (f_label)
                        (void)printf("%-*s ", dp->s_label, np->label);
                if (S_ISCHR(sp->st_mode) || S_ISBLK(sp->st_mode))
                        printdev(dp->s_size, sp->st_rdev);
                else
                        printsize(dp->s_size, sp->st_size);
                if (f_accesstime)
                        printtime(sp->st_atime);
                else if (f_birthtime)
                        printtime(sp->st_birthtime);
                else if (f_statustime)
                        printtime(sp->st_ctime);
                else
                        printtime(sp->st_mtime);
#ifdef COLORLS
                if (f_color)
                        color_printed = colortype(sp->st_mode);
#endif
                (void)printname(p->fts_name);
#ifdef COLORLS
                if (f_color && color_printed)
                        endcolor(0);
#endif
                if (f_type)
                        (void)printtype(sp->st_mode);
                if (S_ISLNK(sp->st_mode))
                        printlink(p);
                (void)putchar('\n');
        }
}

void
printstream(const DISPLAY *dp)
{
        FTSENT *p;
        int chcnt;

        for (p = dp->list, chcnt = 0; p; p = p->fts_link) {
                if (p->fts_number == NO_PRINT)
                        continue;
                /* XXX strlen does not take octal escapes into account. */
                if (strlen(p->fts_name) + chcnt +
                    (p->fts_link ? 2 : 0) >= (unsigned)termwidth) {
                        putchar('\n');
                        chcnt = 0;
                }
                chcnt += printaname(p, dp->s_inode, dp->s_block);
                if (p->fts_link) {
                        printf(", ");
                        chcnt += 2;
                }
        }
        if (chcnt)
                putchar('\n');
}

void
printcol(const DISPLAY *dp)
{
        static FTSENT **array;
        static int lastentries = -1;
        FTSENT *p;
        FTSENT **narray;
        int base;
        int chcnt;
        int cnt;
        int col;
        int colwidth;
        int endcol;
        int num;
        int numcols;
        int numrows;
        int row;
        int tabwidth;

        if (f_notabs)
                tabwidth = 1;
        else
                tabwidth = 8;

        /*
         * Have to do random access in the linked list -- build a table
         * of pointers.
         */
        if (dp->entries > lastentries) {
                if ((narray =
                    realloc(array, dp->entries * sizeof(FTSENT *))) == NULL) {
                        warn(NULL);
                        printscol(dp);
                        return;
                }
                lastentries = dp->entries;
                array = narray;
        }
        for (p = dp->list, num = 0; p; p = p->fts_link)
                if (p->fts_number != NO_PRINT)
                        array[num++] = p;

        colwidth = dp->maxlen;
        if (f_inode)
                colwidth += dp->s_inode + 1;
        if (f_size)
                colwidth += dp->s_block + 1;
        if (f_type)
                colwidth += 1;

        colwidth = (colwidth + tabwidth) & ~(tabwidth - 1);
        if (termwidth < 2 * colwidth) {
                printscol(dp);
                return;
        }
        numcols = termwidth / colwidth;
        numrows = num / numcols;
        if (num % numcols)
                ++numrows;

        if ((dp->list == NULL || dp->list->fts_level != FTS_ROOTLEVEL) &&
            (f_longform || f_size)) {
                (void)printf("total %lu\n", howmany(dp->btotal, blocksize));
        }

        base = 0;
        for (row = 0; row < numrows; ++row) {
                endcol = colwidth;
                if (!f_sortacross)
                        base = row;
                for (col = 0, chcnt = 0; col < numcols; ++col) {
                        chcnt += printaname(array[base], dp->s_inode,
                            dp->s_block);
                        if (f_sortacross)
                                base++;
                        else
                                base += numrows;
                        if (base >= num)
                                break;
                        while ((cnt = ((chcnt + tabwidth) & ~(tabwidth - 1)))
                            <= endcol) {
                                if (f_sortacross && col + 1 >= numcols)
                                        break;
                                (void)putchar(f_notabs ? ' ' : '\t');
                                chcnt = cnt;
                        }
                        endcol += colwidth;
                }
                (void)putchar('\n');
        }
}

/*
 * print [inode] [size] name
 * return # of characters printed, no trailing characters.
 */
static int
printaname(const FTSENT *p, u_long inodefield, u_long sizefield)
{
        struct stat *sp;
        int chcnt;
#ifdef COLORLS
        int color_printed = 0;
#endif

        sp = p->fts_statp;
        chcnt = 0;
        if (f_inode)
                chcnt += printf("%*ju ",
                    (int)inodefield, (uintmax_t)sp->st_ino);
        if (f_size)
                chcnt += printf(f_thousands ? "%'*jd " : "%*jd ",
                    (int)sizefield, howmany(sp->st_blocks, blocksize));
#ifdef COLORLS
        if (f_color)
                color_printed = colortype(sp->st_mode);
#endif
        chcnt += printname(p->fts_name);
#ifdef COLORLS
        if (f_color && color_printed)
                endcolor(0);
#endif
        if (f_type)
                chcnt += printtype(sp->st_mode);
        return (chcnt);
}

/*
 * Print device special file major and minor numbers.
 */
static void
printdev(size_t width, dev_t dev)
{

        (void)printf("%#*jx ", (u_int)width, (uintmax_t)dev);
}

static void
ls_strftime(char *str, size_t len, const char *fmt, const struct tm *tm)
{
        char *posb, nfmt[BUFSIZ];
        const char *format = fmt;

        if ((posb = strstr(fmt, "%b")) != NULL) {
                if (month_max_size == 0) {
                        compute_abbreviated_month_size();
                }
                if (month_max_size > 0 && tm != NULL) {
                        snprintf(nfmt, sizeof(nfmt),  "%.*s%s%*s%s",
                            (int)(posb - fmt), fmt,
                            get_abmon(tm->tm_mon),
                            (int)padding_for_month[tm->tm_mon],
                            "",
                            posb + 2);
                        format = nfmt;
                }
        }
        if (tm != NULL)
                strftime(str, len, format, tm);
        else
                strlcpy(str, "bad date val", len);
}

static void
printtime(time_t ftime)
{
        char longstring[80];
        static time_t now = 0;
        const char *format;
        static int d_first = -1;

        if (d_first < 0)
                d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
        if (now == 0)
                now = time(NULL);

#define SIXMONTHS       ((365 / 2) * 86400)
        if (f_timeformat)  /* user specified format */
                format = f_timeformat;
        else if (f_sectime)
                /* mmm dd hh:mm:ss yyyy || dd mmm hh:mm:ss yyyy */
                format = d_first ? "%e %b %T %Y" : "%b %e %T %Y";
        else if (ftime + SIXMONTHS > now && ftime < now + SIXMONTHS)
                /* mmm dd hh:mm || dd mmm hh:mm */
                format = d_first ? "%e %b %R" : "%b %e %R";
        else
                /* mmm dd  yyyy || dd mmm  yyyy */
                format = d_first ? "%e %b  %Y" : "%b %e  %Y";
        ls_strftime(longstring, sizeof(longstring), format, localtime(&ftime));
        fputs(longstring, stdout);
        fputc(' ', stdout);
}

static int
printtype(u_int mode)
{

        if (f_slash) {
                if ((mode & S_IFMT) == S_IFDIR) {
                        (void)putchar('/');
                        return (1);
                }
                return (0);
        }

        switch (mode & S_IFMT) {
        case S_IFDIR:
                (void)putchar('/');
                return (1);
        case S_IFIFO:
                (void)putchar('|');
                return (1);
        case S_IFLNK:
                (void)putchar('@');
                return (1);
        case S_IFSOCK:
                (void)putchar('=');
                return (1);
        case S_IFWHT:
                (void)putchar('%');
                return (1);
        default:
                break;
        }
        if (mode & (S_IXUSR | S_IXGRP | S_IXOTH)) {
                (void)putchar('*');
                return (1);
        }
        return (0);
}

#ifdef COLORLS
static int
putch(int c)
{
        (void)putchar(c);
        return 0;
}

static int
writech(int c)
{
        char tmp = (char)c;

        (void)write(STDOUT_FILENO, &tmp, 1);
        return 0;
}

static void
printcolor_termcap(Colors c)
{
        char *ansiseq;

        if (colors[c].bold)
                tputs(enter_bold, 1, putch);
        if (colors[c].underline)
                tputs(enter_underline, 1, putch);

        if (colors[c].num[0] != -1) {
                ansiseq = tgoto(ansi_fgcol, 0, colors[c].num[0]);
                if (ansiseq)
                        tputs(ansiseq, 1, putch);
        }
        if (colors[c].num[1] != -1) {
                ansiseq = tgoto(ansi_bgcol, 0, colors[c].num[1]);
                if (ansiseq)
                        tputs(ansiseq, 1, putch);
        }
}

static void
printcolor_ansi(Colors c)
{

        printf("\033[");

        if (colors[c].bold)
                printf("1");
        if (colors[c].underline)
                printf(";4");
        if (colors[c].num[0] != -1)
                printf(";3%d", colors[c].num[0]);
        if (colors[c].num[1] != -1)
                printf(";4%d", colors[c].num[1]);
        printf("m");
}

static void
printcolor(Colors c)
{

        if (explicitansi)
                printcolor_ansi(c);
        else
                printcolor_termcap(c);
}

static void
endcolor_termcap(int sig)
{

        tputs(ansi_coloff, 1, sig ? writech : putch);
        tputs(attrs_off, 1, sig ? writech : putch);
}

static void
endcolor_ansi(void)
{

        printf("\33[m");
}

static void
endcolor(int sig)
{

        if (explicitansi)
                endcolor_ansi();
        else
                endcolor_termcap(sig);
}

static int
colortype(mode_t mode)
{
        switch (mode & S_IFMT) {
        case S_IFDIR:
                if (mode & S_IWOTH)
                        if (mode & S_ISTXT)
                                printcolor(C_WSDIR);
                        else
                                printcolor(C_WDIR);
                else
                        printcolor(C_DIR);
                return (1);
        case S_IFLNK:
                printcolor(C_LNK);
                return (1);
        case S_IFSOCK:
                printcolor(C_SOCK);
                return (1);
        case S_IFIFO:
                printcolor(C_FIFO);
                return (1);
        case S_IFBLK:
                printcolor(C_BLK);
                return (1);
        case S_IFCHR:
                printcolor(C_CHR);
                return (1);
        default:;
        }
        if (mode & (S_IXUSR | S_IXGRP | S_IXOTH)) {
                if (mode & S_ISUID)
                        printcolor(C_SUID);
                else if (mode & S_ISGID)
                        printcolor(C_SGID);
                else
                        printcolor(C_EXEC);
                return (1);
        }
        return (0);
}

void
parsecolors(const char *cs)
{
        int i;
        int j;
        size_t len;
        char c[2];
        short legacy_warn = 0;

        if (cs == NULL)
                cs = "";        /* LSCOLORS not set */
        len = strlen(cs);
        for (i = 0; i < (int)C_NUMCOLORS; i++) {
                colors[i].bold = false;
                colors[i].underline = false;

                if (len <= 2 * (size_t)i) {
                        c[0] = defcolors[2 * i];
                        c[1] = defcolors[2 * i + 1];
                } else {
                        c[0] = cs[2 * i];
                        c[1] = cs[2 * i + 1];
                }
                for (j = 0; j < 2; j++) {
                        /* Legacy colours used 0-7 */
                        if (c[j] >= '0' && c[j] <= '7') {
                                colors[i].num[j] = c[j] - '0';
                                if (!legacy_warn) {
                                        warnx("LSCOLORS should use "
                                            "characters a-h instead of 0-9 ("
                                            "see the manual page)");
                                }
                                legacy_warn = 1;
                        } else if (c[j] >= 'a' && c[j] <= 'h')
                                colors[i].num[j] = c[j] - 'a';
                        else if (c[j] >= 'A' && c[j] <= 'H') {
                                colors[i].num[j] = c[j] - 'A';
                                if (j == 1)
                                        colors[i].underline = true;
                                else
                                        colors[i].bold = true;
                        } else if (tolower((unsigned char)c[j]) == 'x') {
                                if (j == 1 && c[j] == 'X')
                                        colors[i].underline = true;
                                colors[i].num[j] = -1;
                        } else {
                                warnx("invalid character '%c' in LSCOLORS"
                                    " env var", c[j]);
                                colors[i].num[j] = -1;
                        }
                }
        }
}

void
colorquit(int sig)
{
        endcolor(sig);

        (void)signal(sig, SIG_DFL);
        (void)kill(getpid(), sig);
}

#endif /* COLORLS */

static void
printlink(const FTSENT *p)
{
        int lnklen;
        char name[MAXPATHLEN + 1];
        char path[MAXPATHLEN + 1];

        if (p->fts_level == FTS_ROOTLEVEL)
                (void)snprintf(name, sizeof(name), "%s", p->fts_name);
        else
                (void)snprintf(name, sizeof(name),
                    "%s/%s", p->fts_parent->fts_accpath, p->fts_name);
        if ((lnklen = readlink(name, path, sizeof(path) - 1)) == -1) {
                (void)fprintf(stderr, "\nls: %s: %s\n", name, strerror(errno));
                return;
        }
        path[lnklen] = '\0';
        (void)printf(" -> ");
        (void)printname(path);
}

static void
printsize(size_t width, off_t bytes)
{

        if (f_humanval) {
                /*
                 * Reserve one space before the size and allocate room for
                 * the trailing '\0'.
                 */
                char buf[HUMANVALSTR_LEN - 1 + 1];

                humanize_number(buf, sizeof(buf), (int64_t)bytes, "",
                    HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
                (void)printf("%*s ", (u_int)width, buf);
        } else {
                (void)printf(f_thousands ? "%'*jd " : "%*jd ",
                    (u_int)width, bytes);
        }
}

/*
 * Add a + after the standard rwxrwxrwx mode if the file has an
 * ACL. strmode() reserves space at the end of the string.
 */
static void
aclmode(char *buf, const FTSENT *p)
{
        char name[MAXPATHLEN + 1];
        int ret, trivial;
        static dev_t previous_dev = NODEV;
        static int supports_acls = -1;
        static int type = ACL_TYPE_ACCESS;
        acl_t facl;

        /*
         * XXX: ACLs are not supported on whiteouts and device files
         * residing on UFS.
         */
        if (S_ISCHR(p->fts_statp->st_mode) || S_ISBLK(p->fts_statp->st_mode) ||
            S_ISWHT(p->fts_statp->st_mode))
                return;

        if (previous_dev == p->fts_statp->st_dev && supports_acls == 0)
                return;

        if (p->fts_level == FTS_ROOTLEVEL)
                snprintf(name, sizeof(name), "%s", p->fts_name);
        else
                snprintf(name, sizeof(name), "%s/%s",
                    p->fts_parent->fts_accpath, p->fts_name);

        if (previous_dev != p->fts_statp->st_dev) {
                previous_dev = p->fts_statp->st_dev;
                supports_acls = 0;

                ret = lpathconf(name, _PC_ACL_NFS4);
                if (ret > 0) {
                        type = ACL_TYPE_NFS4;
                        supports_acls = 1;
                } else if (ret < 0 && errno != EINVAL) {
                        warn("%s", name);
                        return;
                }
                if (supports_acls == 0) {
                        ret = lpathconf(name, _PC_ACL_EXTENDED);
                        if (ret > 0) {
                                type = ACL_TYPE_ACCESS;
                                supports_acls = 1;
                        } else if (ret < 0 && errno != EINVAL) {
                                warn("%s", name);
                                return;
                        }
                }
        }
        if (supports_acls == 0)
                return;
        facl = acl_get_link_np(name, type);
        if (facl == NULL) {
                warn("%s", name);
                return;
        }
        if (acl_is_trivial_np(facl, &trivial)) {
                acl_free(facl);
                warn("%s", name);
                return;
        }
        if (!trivial)
                buf[10] = '+';
        acl_free(facl);
}