Imported from util-linux-2.11y tarball.

[thirdparty/util-linux.git] / text-utils / more.c

/*
 * Copyright (C) 1980 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

/*
** more.c - General purpose tty output filter and file perusal program
**
**      by Eric Shienbrood, UC Berkeley
**
**      modified by Geoff Peck, UCB to add underlining, single spacing
**      modified by John Foderaro, UCB to add -c and MORE environment variable
**      modified by Erik Troan <ewt@redhat.com> to be more posix and so compile
**        on linux/axp.
**      modified by Kars de Jong <jongk@cs.utwente.nl> to use terminfo instead
**        of termcap.
        1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
        - added Native Language Support
        1999-03-19 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
        - more nls translatable strings
        1999-05-09 aeb - applied a RedHat patch (setjmp->sigsetjmp); without it
        a second ^Z would fail.
        1999-05-09 aeb - undone Kars' work, so that more works without
        libcurses (and hence can be in /bin with libcurses being in /usr/lib
        which may not be mounted). However, when termcap is not present curses
        can still be used.
*/

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>             /* for alloca() */
#include <stdarg.h>             /* for va_start() etc */
#include <sys/param.h>
#include <ctype.h>
#include <signal.h>
#include <errno.h>
#include <termios.h>
#include <setjmp.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/wait.h>
#include <a.out.h>
#include <locale.h>
#include "xstrncpy.h"
#include "nls.h"
#include "widechar.h"

#define _REGEX_RE_COMP
#include <regex.h>
#undef _REGEX_RE_COMP

#define VI              "vi"    /* found on the user's path */

#define Fopen(s,m)      (Currline = 0,file_pos=0,fopen(s,m))
#define Ftell(f)        file_pos
#define Fseek(f,off)    (file_pos=off,fseek(f,off,0))
#define Getc(f)         (++file_pos, getc(f))
#define Ungetc(c,f)     (--file_pos, ungetc(c,f))

#define stty(fd,argp)  tcsetattr(fd,TCSANOW,argp)

/* some function declarations */
void initterm(void);
void kill_line(void);
void doclear(void);
void cleareol(void);
void clreos(void);
void home(void);
void error (char *mess);
void do_shell (char *filename);
int  colon (char *filename, int cmd, int nlines);
int  expand (char **outbuf, char *inbuf);
void argscan(char *s,char *argv0);
void rdline (register FILE *f);
void copy_file(register FILE *f);
void search(char buf[], FILE *file, register int n);
void skipf (register int nskip);
void skiplns(register int n, register FILE *f);
void screen (register FILE *f, register int num_lines);
int  command (char *filename, register FILE *f);
void erasep (register int col);
void show (register char ch);
int  pr(char *s1);
int  printd (int n);
void set_tty(void);
void reset_tty(void);
void ttyin (unsigned char buf[], register int nmax, char pchar);
int  number(char *cmd);
int  readch (void);
int  get_line(register FILE *f, int *length);
void prbuf (register char *s, register int n);
int  xprintf (char *fmt, ...);
void execute (char *filename, char *cmd, ...);
void errwrite (char *txt);
void errwrite1 (char *sym);
FILE *checkf (char *, int *);

#define TBUFSIZ 1024
#define LINSIZ  256
#define ctrl(letter)    (letter & 077)
#define RUBOUT  '\177'
#define ESC     '\033'
#define QUIT    '\034'

struct termios  otty, savetty0;
long            file_pos, file_size;
int             fnum, no_intty, no_tty, slow_tty;
int             dum_opt, dlines;
void            onquit(int), onsusp(int), chgwinsz(int), end_it(int);
int             nscroll = 11;   /* Number of lines scrolled by 'd' */
int             fold_opt = 1;   /* Fold long lines */
int             stop_opt = 1;   /* Stop after form feeds */
int             ssp_opt = 0;    /* Suppress white space */
int             ul_opt = 1;     /* Underline as best we can */
int             promptlen;
int             Currline;       /* Line we are currently at */
int             startup = 1;
int             firstf = 1;
int             notell = 1;
int             docrterase = 0;
int             docrtkill = 0;
int             bad_so; /* True if overwriting does not turn off standout */
int             inwait, Pause, errors;
int             within; /* true if we are within a file,
                        false if we are between files */
int             hard, dumb, noscroll, hardtabs, clreol, eatnl;
int             catch_susp;     /* We should catch the SIGTSTP signal */
char            **fnames;       /* The list of file names */
int             nfiles;         /* Number of files left to process */
char            *shell;         /* The name of the shell to use */
int             shellp;         /* A previous shell command exists */
sigjmp_buf      restore;
char            Line[LINSIZ+2]; /* Line buffer */
int             Lpp = 24;       /* lines per page */
char            *Clear;         /* clear screen */
char            *eraseln;       /* erase line */
char            *Senter, *Sexit;/* enter and exit standout mode */
char            *ULenter, *ULexit;      /* enter and exit underline mode */
char            *chUL;          /* underline character */
char            *chBS;          /* backspace character */
char            *Home;          /* go to home */
char            *cursorm;       /* cursor movement */
char            cursorhome[40]; /* contains cursor movement to home */
char            *EodClr;        /* clear rest of screen */
int             Mcol = 80;      /* number of columns */
int             Wrap = 1;       /* set if automargins */
int             soglitch;       /* terminal has standout mode glitch */
int             ulglitch;       /* terminal has underline mode glitch */
int             pstate = 0;     /* current UL state */
static int      magic(FILE *, char *);
struct {
    long chrctr, line;
} context, screen_start;
extern char     PC;             /* pad character */

#ifndef HAVE_termcap
#define USE_CURSES
#endif

#ifdef USE_CURSES

#if NCH
#include <ncurses.h>
#else
#include <curses.h>
#endif
#include <term.h>                       /* include after <curses.h> */

static void
my_putstring(char *s) {
     putp(s);
}

static void
my_setupterm(const char *term, int fildes, int *errret) {
     setupterm(term, fildes, errret);
}

static int
my_tgetnum(char *s, char *ss) {
     return tigetnum(ss);
}

static int
my_tgetflag(char *s, char *ss) {
     return tigetflag(ss);
}

static char *
my_tgetstr(char *s, char *ss) {
     return tigetstr(ss);
}

static char *
my_tgoto(const char *cap, int col, int row) {
     return tparm(cap, col, row);
}

#else /* no CURSES */
#include <termcap.h>

char termbuffer[4096];
char tcbuffer[4096];
char *strbuf = termbuffer;

static void
my_putstring(char *s) {
     tputs (s, 1, putchar);
}

static void
my_setupterm(const char *term, int fildes, int *errret) {
     *errret = tgetent(tcbuffer, term);
}

static int
my_tgetnum(char *s, char *ss) {
     return tgetnum(s);
}

static int
my_tgetflag(char *s, char *ss) {
     return tgetflag(s);
}

static char *
my_tgetstr(char *s, char *ss) {
     return tgetstr(s, &strbuf);
}

static char *
my_tgoto(const char *cap, int col, int row) {
     return tgoto(cap, col, row);
}


#endif /* USE_CURSES */

static void
idummy(int *kk) {}

static void
Fdummy(FILE **ff) {}

static void
usage(char *s) {
        char *p = strrchr(s, '/');
        fprintf(stderr,
                _("usage: %s [-dflpcsu] [+linenum | +/pattern] name1 name2 ...\n"),
                p ? p + 1 : s);
}

int main(int argc, char **argv) {
    FILE        *f;
    char        *s;
    char        *p;
    int         ch;
    int         left;
    int         prnames = 0;
    int         initopt = 0;
    int         srchopt = 0;
    int         clearit = 0;
    int         initline = 0;
    char        initbuf[80];

    setlocale(LC_ALL, "");
    bindtextdomain(PACKAGE, LOCALEDIR);
    textdomain(PACKAGE);
    
    /* avoid gcc complaints about register variables that
       may be clobbered by a longjmp, by forcing our variables here
       to be non-register */
    Fdummy(&f); idummy(&left); idummy(&prnames);
    idummy(&initopt); idummy(&srchopt); idummy(&initline);

    nfiles = argc;
    fnames = argv;
    setlocale(LC_ALL, "");
    initterm ();
    nscroll = Lpp/2 - 1;
    if (nscroll <= 0)
        nscroll = 1;
    if((s = getenv("MORE")) != NULL) argscan(s,argv[0]);
    while (--nfiles > 0) {
        if ((ch = (*++fnames)[0]) == '-') {
            argscan(*fnames+1,argv[0]);
        }
        else if (ch == '+') {
            s = *fnames;
            if (*++s == '/') {
                srchopt++;
                for (++s, p = initbuf; p < initbuf + 79 && *s != '\0';)
                    *p++ = *s++;
                *p = '\0';
            }
            else {
                initopt++;
                for (initline = 0; *s != '\0'; s++)
                    if (isdigit (*s))
                        initline = initline*10 + *s -'0';
                --initline;
            }
        }
        else break;
    }
    /* allow clreol only if Home and eraseln and EodClr strings are
     *  defined, and in that case, make sure we are in noscroll mode
     */
    if(clreol)
    {
        if((Home == NULL) || (*Home == '\0') ||
           (eraseln == NULL) || (*eraseln == '\0') ||
           (EodClr == NULL) || (*EodClr == '\0') )
              clreol = 0;
        else noscroll = 1;
    }
    if (dlines == 0)
        dlines = Lpp - (noscroll ? 1 : 2);
    left = dlines;
    if (nfiles > 1)
        prnames++;
    if (!no_intty && nfiles == 0) {
        usage(argv[0]);
        exit(1);
    }
    else
        f = stdin;
    if (!no_tty) {
        signal(SIGQUIT, onquit);
        signal(SIGINT, end_it);
#ifdef SIGWINCH
        signal(SIGWINCH, chgwinsz);
#endif
        if (signal (SIGTSTP, SIG_IGN) == SIG_DFL) {
            signal(SIGTSTP, onsusp);
            catch_susp++;
        }
        stty (fileno(stderr), &otty);
    }
    if (no_intty) {
        if (no_tty)
            copy_file (stdin);
        else {
            if ((ch = Getc (f)) == '\f')
                doclear();
            else {
                Ungetc (ch, f);
                if (noscroll && (ch != EOF)) {
                    if (clreol)
                        home ();
                    else
                        doclear ();
                }
            }
            if (srchopt)
            {
                search (initbuf, stdin, 1);
                if (noscroll)
                    left--;
            }
            else if (initopt)
                skiplns (initline, stdin);
            screen (stdin, left);
        }
        no_intty = 0;
        prnames++;
        firstf = 0;
    }

    while (fnum < nfiles) {
        if ((f = checkf (fnames[fnum], &clearit)) != NULL) {
            context.line = context.chrctr = 0;
            Currline = 0;
            if (firstf) sigsetjmp (restore, 1);
            if (firstf) {
                firstf = 0;
                if (srchopt) {
                    search (initbuf, f, 1);
                    if (noscroll)
                        left--;
                }
                else if (initopt)
                    skiplns (initline, f);
            }
            else if (fnum < nfiles && !no_tty) {
                sigsetjmp (restore, 1);
                left = command (fnames[fnum], f);
            }
            if (left != 0) {
                if ((noscroll || clearit) && (file_size != LONG_MAX)) {
                    if (clreol)
                        home ();
                    else
                        doclear ();
                }
                if (prnames) {
                    if (bad_so)
                        erasep (0);
                    if (clreol)
                        cleareol ();
                    pr("::::::::::::::");
                    if (promptlen > 14)
                        erasep (14);
                    xprintf ("\n");
                    if(clreol) cleareol();
                    xprintf("%s\n", fnames[fnum]);
                    if(clreol) cleareol();
                    xprintf("::::::::::::::\n");
                    if (left > Lpp - 4)
                        left = Lpp - 4;
                }
                if (no_tty)
                    copy_file (f);
                else {
                    within++;
                    screen(f, left);
                    within = 0;
                }
            }
            sigsetjmp (restore, 1);
            fflush(stdout);
            fclose(f);
            screen_start.line = screen_start.chrctr = 0L;
            context.line = context.chrctr = 0L;
        }
        fnum++;
        firstf = 0;
    }
    reset_tty ();
    exit(0);
}

void argscan(char *s, char *argv0) {
        int seen_num = 0;

        while (*s != '\0') {
                switch (*s) {
                  case '0': case '1': case '2':
                  case '3': case '4': case '5':
                  case '6': case '7': case '8':
                  case '9':
                        if (!seen_num) {
                                dlines = 0;
                                seen_num = 1;
                        }
                        dlines = dlines*10 + *s - '0';
                        break;
                  case 'd':
                        dum_opt = 1;
                        break;
                  case 'l':
                        stop_opt = 0;
                        break;
                  case 'f':
                        fold_opt = 0;
                        break;
                  case 'p':
                        noscroll++;
                        break;
                  case 'c':
                        clreol++;
                        break;
                  case 's':
                        ssp_opt = 1;
                        break;
                  case 'u':
                        ul_opt = 0;
                        break;
                  case '-': case ' ': case '\t':
                        break;
                  default:
                        fputs(argv0,stderr);
                        fputs(": unknown option \"-",stderr);
                        putc(*s,stderr);
                        fputs("\"\n",stderr);
                        usage(argv0);
                        exit(1);
                        break;
                }
                s++;
        }
}


/*
** Check whether the file named by fs is an ASCII file which the user may
** access.  If it is, return the opened file. Otherwise return NULL.
*/

FILE *
checkf (fs, clearfirst)
        register char *fs;
        int *clearfirst;
{
        struct stat stbuf;
        register FILE *f;
        int c;

        if (stat (fs, &stbuf) == -1) {
                (void)fflush(stdout);
                if (clreol)
                        cleareol ();
                perror(fs);
                return((FILE *)NULL);
        }
        if ((stbuf.st_mode & S_IFMT) == S_IFDIR) {
                xprintf(_("\n*** %s: directory ***\n\n"), fs);
                return((FILE *)NULL);
        }
        if ((f = Fopen(fs, "r")) == NULL) {
                (void)fflush(stdout);
                perror(fs);
                return((FILE *)NULL);
        }
        if (magic(f, fs))
                return((FILE *)NULL);
        c = Getc(f);
        *clearfirst = (c == '\f');
        Ungetc (c, f);
        if ((file_size = stbuf.st_size) == 0)
                file_size = LONG_MAX;
        return(f);
}

/*
 * magic --
 *      check for file magic numbers.  This code would best be shared with
 *      the file(1) program or, perhaps, more should not try and be so smart?
 */
static int
magic(f, fs)
        FILE *f;
        char *fs;
{
        char twobytes[2];

        /* don't try to look ahead if the input is unseekable */
        if (fseek(f, 0L, SEEK_SET))
                return(0);

        if (fread(twobytes, 2, 1, f) == 1) {
                switch(twobytes[0] + (twobytes[1]<<8)) {
                case OMAGIC:    /* 0407 */
                case NMAGIC:    /* 0410 */
                case ZMAGIC:    /* 0413 */
                case 0405:
                case 0411:
                case 0177545:
                case 0x457f:            /* simple ELF detection */
                        xprintf(_("\n******** %s: Not a text file ********\n\n"), fs);
                        (void)fclose(f);
                        return(1);
                }
        }
        (void)fseek(f, 0L, SEEK_SET);           /* rewind() not necessary */
        return(0);
}

/*
** Print out the contents of the file f, one screenful at a time.
*/

#define STOP -10

void screen (register FILE *f, register int num_lines)
{
    register int c;
    register int nchars;
    int length;                 /* length of current line */
    static int prev_len = 1;    /* length of previous line */

    for (;;) {
        while (num_lines > 0 && !Pause) {
            if ((nchars = get_line (f, &length)) == EOF)
            {
                if (clreol)
                    clreos();
                return;
            }
            if (ssp_opt && length == 0 && prev_len == 0)
                continue;
            prev_len = length;
            if (bad_so || ((Senter && *Senter == ' ') && (promptlen > 0)))
                erasep (0);
            /* must clear before drawing line since tabs on some terminals
             * do not erase what they tab over.
             */
            if (clreol)
                cleareol ();
            prbuf (Line, length);
            if (nchars < promptlen)
                erasep (nchars);        /* erasep () sets promptlen to 0 */
            else promptlen = 0;
            /* is this needed?
             * if (clreol)
             *  cleareol();     * must clear again in case we wrapped *
             */
            if (nchars < Mcol || !fold_opt)
                prbuf("\n", 1); /* will turn off UL if necessary */
            if (nchars == STOP)
                break;
            num_lines--;
        }
        if (pstate) {
                my_putstring (ULexit);
                pstate = 0;
        }
        fflush(stdout);
        if ((c = Getc(f)) == EOF)
        {
            if (clreol)
                clreos ();
            return;
        }

        if (Pause && clreol)
            clreos ();
        Ungetc (c, f);
        sigsetjmp (restore, 1);
        Pause = 0; startup = 0;
        if ((num_lines = command (NULL, f)) == 0)
            return;
        if (hard && promptlen > 0)
                erasep (0);
        if (noscroll && num_lines >= dlines)
        {
            if (clreol)
                home();
            else
                doclear ();
        }
        screen_start.line = Currline;
        screen_start.chrctr = Ftell (f);
    }
}

/*
** Come here if a quit signal is received
*/

void onquit(int dummy) {
    signal(SIGQUIT, SIG_IGN);
    if (!inwait) {
        putchar ('\n');
        if (!startup) {
            signal(SIGQUIT, onquit);
            siglongjmp (restore, 1);
        }
        else
            Pause++;
    }
    else if (!dum_opt && notell) {
        char *s = _("[Use q or Q to quit]");
        errwrite(s);
        promptlen += strlen(s);
        notell = 0;
    }
    signal(SIGQUIT, onquit);
}

/*
** Come here if a signal for a window size change is received
*/

#ifdef SIGWINCH
void chgwinsz(int dummy) {
    struct winsize win;

    (void) signal(SIGWINCH, SIG_IGN);
    if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1) {
        if (win.ws_row != 0) {
            Lpp = win.ws_row;
            nscroll = Lpp/2 - 1;
            if (nscroll <= 0)
                nscroll = 1;
            dlines = Lpp - (noscroll ? 1 : 2);
        }
        if (win.ws_col != 0)
            Mcol = win.ws_col;
    }
    (void) signal(SIGWINCH, chgwinsz);
}
#endif

/*
** Clean up terminal state and exit. Also come here if interrupt signal received
*/

void end_it (int dummy) {
    reset_tty ();
    if (clreol) {
        putchar ('\r');
        clreos ();
        fflush (stdout);
    }
    else if (!clreol && (promptlen > 0)) {
        kill_line ();
        fflush (stdout);
    }
    else
        errwrite("\n");
    _exit(0);
}

void copy_file(register FILE *f) {
    register int c;

    while ((c = getc(f)) != EOF)
        putchar(c);
}

/* Simplified printf function */

int xprintf (char *fmt, ...) {
        va_list ap;
        char ch;
        int ccount;

        ccount = 0;
        va_start(ap, fmt);
        while (*fmt) {
                while ((ch = *fmt++) != '%') {
                        if (ch == '\0')
                                return (ccount);
                        ccount++;
                        putchar (ch);
                }
                switch (*fmt++) {
                case 'd':
                        ccount += printd (va_arg(ap, int));
                        break;
                case 's':
                        ccount += pr (va_arg(ap, char *));
                        break;
                case '%':
                        ccount++;
                        putchar ('%');
                        break;
                case '0':
                        return (ccount);
                default:
                        break;
                }
        }
        va_end(ap);
        return (ccount);

}

/*
** Print an integer as a string of decimal digits,
** returning the length of the print representation.
*/

int printd (int n)
{
    int a, nchars;

    if ((a = n/10) != 0)
        nchars = 1 + printd(a);
    else
        nchars = 1;
    putchar (n % 10 + '0');
    return (nchars);
}

/* Put the print representation of an integer into a string */
static char *sptr;

static void Sprintf (int n) {
    int a;

    if ((a = n/10) != 0)
        Sprintf (a);
    *sptr++ = n % 10 + '0';
}

static void scanstr (int n, char *str)
{
    sptr = str;
    Sprintf (n);
    *sptr = '\0';
}

#define ringbell()      errwrite("\007");

#ifdef undef
strlen (s)
char *s;
{
    register char *p;

    p = s;
    while (*p++)
        ;
    return (p - s - 1);
}
#endif

/* See whether the last component of the path name "path" is equal to the
** string "string"
*/

static int tailequ (char *path, register char *string)
{
        register char *tail;

        tail = path + strlen(path);
        while (--tail >= path)
                if (*tail == '/')
                        break;
        ++tail;
        while (*tail++ == *string++)
                if (*tail == '\0')
                        return(1);
        return(0);
}

static void prompt (char *filename)
{
    if (clreol)
        cleareol ();
    else if (promptlen > 0)
        kill_line ();
    if (!hard) {
        promptlen = 0;
        if (Senter && Sexit) {
            my_putstring (Senter);
            promptlen += (2 * soglitch);
        }
        if (clreol)
            cleareol ();
        promptlen += pr(_("--More--"));
        if (filename != NULL) {
            promptlen += xprintf (_("(Next file: %s)"), filename);
        } else if (!no_intty) {
            promptlen += xprintf ("(%d%%)",
                                  (int)((file_pos * 100) / file_size));
        }
        if (dum_opt) {
            promptlen += pr(_("[Press space to continue, 'q' to quit.]"));
        }
        if (Senter && Sexit)
            my_putstring (Sexit);
        if (clreol)
            clreos ();
        fflush(stdout);
    }
    else
        ringbell();
    inwait++;
}

/*
 * Get a logical line
 */

int get_line(register FILE *f, int *length)
{
    int c;
    char *p;
    int column;
    static int colflg;

#ifdef ENABLE_WIDECHAR
    int i;
    wchar_t wc;
    int wc_width;
    mbstate_t state, state_bak;         /* Current status of the stream. */
    unsigned char mbc[MB_LEN_MAX];      /* Buffer for one multibyte char. */
    size_t mblength;                    /* Byte length of multibyte char. */
    size_t mbc_pos = 0;                 /* Postion of the MBC. */
    int use_mbc_buffer_flag = 0;        /* If 1, mbc has data. */
    int break_flag = 0;                 /* If 1, exit while(). */
    long file_pos_bak = Ftell (f);

    memset (&state, '\0', sizeof (mbstate_t));
#endif

    p = Line;
    column = 0;
    c = Getc (f);
    if (colflg && c == '\n') {
        Currline++;
        c = Getc (f);
    }
    while (p < &Line[LINSIZ - 1]) {
#ifdef ENABLE_WIDECHAR
        if (fold_opt && use_mbc_buffer_flag && MB_CUR_MAX > 1) {
            use_mbc_buffer_flag = 0;
            state_bak = state;
            mbc[mbc_pos++] = c;
process_mbc:
            mblength = mbrtowc (&wc, mbc, mbc_pos, &state);

            switch (mblength) {
              case (size_t)-2:    /* Incomplete multibyte character. */
                use_mbc_buffer_flag = 1;
                state = state_bak;
                break;

              case (size_t)-1:    /* Invalid as a multibyte character. */
                *p++ = mbc[0];
                state = state_bak;
                column++;
                file_pos_bak++;
                
                if (column >= Mcol) {
                    Fseek (f, file_pos_bak);
                } else {
                    memmove (mbc, mbc + 1, --mbc_pos);
                    if (mbc_pos > 0) {
                        mbc[mbc_pos] = '\0';
                        goto process_mbc;
                    }
                }
                break;

              default:
                wc_width = wcwidth (wc);

                if (column + wc_width > Mcol) {
                    Fseek (f, file_pos_bak);
                    break_flag = 1;
                } else {
                    for (i = 0; i < mbc_pos; i++)
                      *p++ = mbc[i];
                    if (wc_width > 0)
                      column += wc_width;
                }
            }

            if (break_flag || column >= Mcol)
              break;

            c = Getc (f);
            continue;
        }
#endif 
        if (c == EOF) {
            if (p > Line) {
                *p = '\0';
                *length = p - Line;
                return (column);
            }
            *length = p - Line;
            return (EOF);
        }
        if (c == '\n') {
            Currline++;
            break;
        }

        *p++ = c;
#if 0
        if (c == '\033') {      /* ESC */
                c = Getc(f);
                while (c > ' ' && c < '0' && p < &Line[LINSIZ - 1]) {
                        *p++ = c;
                        c = Getc(f);
                }
                if (c >= '0' && c < '\177' && p < &Line[LINSIZ - 1]) {
                        *p++ = c;
                        c = Getc(f);
                        continue;
                }
        }
#endif
        if (c == '\t') {
            if (!hardtabs || (column < promptlen && !hard)) {
                if (hardtabs && eraseln && !dumb) {
                    column = 1 + (column | 7);
                    my_putstring (eraseln);
                    promptlen = 0;
                }
                else {
                    for (--p; p < &Line[LINSIZ - 1];) {
                        *p++ = ' ';
                        if ((++column & 7) == 0)
                            break;
                    }
                    if (column >= promptlen) promptlen = 0;
                }
            } else
                column = 1 + (column | 7);
        } else if (c == '\b' && column > 0) {
            column--;
        } else if (c == '\r') {
            int next = Getc(f);
            if (next == '\n') {
                p--;
                Currline++;
                break;
            }
            Ungetc(next,f);
            column = 0;
        } else if (c == '\f' && stop_opt) {
                p[-1] = '^';
                *p++ = 'L';
                column += 2;
                Pause++;
        } else if (c == EOF) {
            *length = p - Line;
            return (column);
        } else {
#ifdef ENABLE_WIDECHAR
            if (fold_opt && MB_CUR_MAX > 1) {
                memset (mbc, '\0', MB_LEN_MAX);
                mbc_pos = 0;
                mbc[mbc_pos++] = c;
                state_bak = state;

                mblength = mbrtowc (&wc, mbc, mbc_pos, &state);

                /* The value of mblength is always less than 2 here. */
                switch (mblength) {
                  case (size_t)-2:
                    p--;
                    file_pos_bak = Ftell (f) - 1;
                    state = state_bak;
                    use_mbc_buffer_flag = 1;
                    break;

                  case (size_t)-1:
                    state = state_bak;
                    column++;
                    break;

                  default:
                    wc_width = wcwidth (wc);
                    if (wc_width > 0)
                      column += wc_width;
                }
            } else
#endif
              {
                if (isprint(c))
                   column++;
              }
        }

        if (column >= Mcol && fold_opt)
                break;
        c = Getc (f);
    }
    if (column >= Mcol && Mcol > 0) {
        if (!Wrap) {
            *p++ = '\n';
        }
    }
    colflg = column == Mcol && fold_opt;
    if (colflg && eatnl && Wrap) {
        *p++ = '\n'; /* simulate normal wrap */
    }
    *length = p - Line;
    *p = 0;
    return (column);
}

/*
** Erase the rest of the prompt, assuming we are starting at column col.
*/

void erasep (register int col)
{

    if (promptlen == 0)
        return;
    if (hard) {
        putchar ('\n');
    }
    else {
        if (col == 0)
            putchar ('\r');
        if (!dumb && eraseln)
            my_putstring (eraseln);
        else
            for (col = promptlen - col; col > 0; col--)
                putchar (' ');
    }
    promptlen = 0;
}

/*
** Erase the current line entirely
*/

void kill_line ()
{
    erasep (0);
    if (!eraseln || dumb)
        putchar ('\r');
}

/*
 * force clear to end of line
 */
void cleareol()
{
    my_putstring(eraseln);
}

void clreos()
{
    my_putstring(EodClr);
}

/*
**  Print string and return number of characters
*/

int pr(char *s1)
{
    register char       *s;
    register char       c;

    for (s = s1; (c = *s++) != 0; )
        putchar(c);
    return (int) (s - s1 - 1);
}


/* Print a buffer of n characters */

void prbuf (register char *s, register int n)
{
    register char c;                    /* next output character */
    register int state;                 /* next output char's UL state */
#define wouldul(s,n)    ((n) >= 2 && (((s)[0] == '_' && (s)[1] == '\b') || ((s)[1] == '\b' && (s)[2] == '_')))

    while (--n >= 0)
        if (!ul_opt)
            putchar (*s++);
        else {
            if (*s == ' ' && pstate == 0 && ulglitch && wouldul(s+1, n-1)) {
                s++;
                continue;
            }
            if ((state = wouldul(s, n)) != 0) {
                c = (*s == '_')? s[2] : *s ;
                n -= 2;
                s += 3;
            } else
                c = *s++;
            if (state != pstate) {
                if (c == ' ' && state == 0 && ulglitch && wouldul(s, n-1))
                    state = 1;
                else
                    my_putstring(state ? ULenter : ULexit);
            }
            if (c != ' ' || pstate == 0 || state != 0 || ulglitch == 0)
                putchar(c);
            if (state && *chUL) {
                pr(chBS);
                my_putstring(chUL);
            }
            pstate = state;
        }
}

/*
**  Clear the screen
*/
void
doclear()
{
    if (Clear && !hard) {
        my_putstring(Clear);

        /* Put out carriage return so that system doesn't
        ** get confused by escape sequences when expanding tabs
        */
        putchar ('\r');
        promptlen = 0;
    }
}

/*
 * Go to home position
 */
void
home()
{
    my_putstring(Home);
}

static int lastcmd, lastarg, lastp;
static int lastcolon;
char shell_line[1000];

/*
** Read a command and do it. A command consists of an optional integer
** argument followed by the command character.  Return the number of lines
** to display in the next screenful.  If there is nothing more to display
** in the current file, zero is returned.
*/

int command (char *filename, register FILE *f)
{
    register int nlines;
    register int retval = 0;
    register int c;
    char colonch;
    int done;
    char comchar, cmdbuf[80];

#define ret(val) retval=val;done++;break

    done = 0;
    if (!errors)
        prompt (filename);
    else
        errors = 0;
    for (;;) {
        nlines = number (&comchar);
        lastp = colonch = 0;
        if (comchar == '.') {   /* Repeat last command */
                lastp++;
                comchar = lastcmd;
                nlines = lastarg;
                if (lastcmd == ':')
                        colonch = lastcolon;
        }
        lastcmd = comchar;
        lastarg = nlines;
        if ((cc_t) comchar == otty.c_cc[VERASE]) {
            kill_line ();
            prompt (filename);
            continue;
        }
        switch (comchar) {
        case ':':
            retval = colon (filename, colonch, nlines);
            if (retval >= 0)
                done++;
            break;
        case 'b':
        case ctrl('B'):
            {
                register int initline;

                if (no_intty) {
                    ringbell();
                    return (-1);
                }

                if (nlines == 0) nlines++;

                putchar ('\r');
                erasep (0);
                xprintf ("\n");
                if (clreol)
                        cleareol ();
                if (nlines != 1)
                        xprintf (_("...back %d pages"), nlines);
                else
                        xprintf (_("...back 1 page"));
                if (clreol)
                        cleareol ();
                pr ("\n");

                initline = Currline - dlines * (nlines + 1);
                if (! noscroll)
                    --initline;
                if (initline < 0) initline = 0;
                Fseek(f, 0L);
                Currline = 0;   /* skiplns() will make Currline correct */
                skiplns(initline, f);
                if (! noscroll) {
                    ret(dlines + 1);
                }
                else {
                    ret(dlines);
                }
            }
        case ' ':
        case 'z':
            if (nlines == 0) nlines = dlines;
            else if (comchar == 'z') dlines = nlines;
            ret (nlines);
        case 'd':
        case ctrl('D'):
            if (nlines != 0) nscroll = nlines;
            ret (nscroll);
        case 'q':
        case 'Q':
            end_it (0);
        case 's':
        case 'f':
            if (nlines == 0) nlines++;
            if (comchar == 'f')
                nlines *= dlines;
            putchar ('\r');
            erasep (0);
            xprintf ("\n");
            if (clreol)
                cleareol ();
            if (nlines == 1)
                    xprintf (_("...skipping one line"));
            else
                    xprintf (_("...skipping %d lines"), nlines);

            if (clreol)
                cleareol ();
            pr ("\n");

            while (nlines > 0) {
                while ((c = Getc (f)) != '\n')
                    if (c == EOF) {
                        retval = 0;
                        done++;
                        goto endsw;
                    }
                    Currline++;
                    nlines--;
            }
            ret (dlines);
        case '\n':
            if (nlines != 0)
                dlines = nlines;
            else
                nlines = 1;
            ret (nlines);
        case '\f':
            if (!no_intty) {
                doclear ();
                Fseek (f, screen_start.chrctr);
                Currline = screen_start.line;
                ret (dlines);
            }
            else {
                ringbell();
                break;
            }
        case '\'':
            if (!no_intty) {
                kill_line ();
                pr (_("\n***Back***\n\n"));
                Fseek (f, context.chrctr);
                Currline = context.line;
                ret (dlines);
            }
            else {
                ringbell();
                break;
            }
        case '=':
            kill_line ();
            promptlen = printd (Currline);
            fflush (stdout);
            break;
        case 'n':
            lastp++;
        case '/':
            if (nlines == 0) nlines++;
            kill_line ();
            pr ("/");
            promptlen = 1;
            fflush (stdout);
            if (lastp) {
                errwrite ("\r");
                search (NULL, f, nlines);       /* Use previous r.e. */
            }
            else {
                ttyin (cmdbuf, sizeof(cmdbuf)-2, '/');
                errwrite("\r");
                search (cmdbuf, f, nlines);
            }
            ret (dlines-1);
        case '!':
            do_shell (filename);
            break;
        case '?':
        case 'h':
            if (noscroll) doclear();
            xprintf(_("\nMost commands optionally preceded by integer argument"
                " k.  Defaults in brackets.\n"
                "Star (*) indicates argument becomes new default.\n"));
            xprintf("---------------------------------------"
                "----------------------------------------\n");
            xprintf(_("<space>\t\t\t"
                        "Display next k lines of text [current screen size]\n"
                "z\t\t\tDisplay next k lines of text [current screen size]*\n"
                "<return>\t\tDisplay next k lines of text [1]*\n"
                "d or ctrl-D\t\t"
                        "Scroll k lines [current scroll size, initially 11]*\n"
                "q or Q or <interrupt>\tExit from more\n"
                "s\t\t\tSkip forward k lines of text [1]\n"
                "f\t\t\tSkip forward k screenfuls of text [1]\n"
                "b or ctrl-B\t\tSkip backwards k screenfuls of text [1]\n"
                "'\t\t\tGo to place where previous search started\n"
                "=\t\t\tDisplay current line number\n"
                "/<regular expression>\t"
                        "Search for kth occurrence of regular expression [1]\n"
                "n\t\t\tSearch for kth occurrence of last r.e [1]\n"
                "!<cmd> or :!<cmd>\tExecute <cmd> in a subshell\n"
                "v\t\t\tStart up /usr/bin/vi at current line\n"
                "ctrl-L\t\t\tRedraw screen\n"
                ":n\t\t\tGo to kth next file [1]\n"
                ":p\t\t\tGo to kth previous file [1]\n"
                ":f\t\t\tDisplay current file name and line number\n"
                ".\t\t\tRepeat previous command\n"));
            xprintf("---------------------------------------"
                "----------------------------------------\n");
            prompt(filename);
            break;
        case 'v':       /* This case should go right before default */
            if (!no_intty) {
                    char *editor;

                    editor = getenv("VISUAL");
                    if (editor == NULL || *editor == '\0')
                            editor = getenv("EDITOR");
                    if (editor == NULL || *editor == '\0')
                            editor = VI;

                    kill_line ();
                    cmdbuf[0] = '+';
                    scanstr (Currline - dlines <= 0 ? 1
                             : Currline - (dlines + 1) / 2, &cmdbuf[1]);
                    pr (editor); putchar (' ');
                    pr (cmdbuf); putchar (' '); pr (fnames[fnum]);
                    execute (filename, editor, editor, cmdbuf, fnames[fnum], 0);
                    break;
            }
        default:
            if (dum_opt) {
                kill_line ();
                if (Senter && Sexit) {
                    my_putstring (Senter);
                    promptlen = pr (_("[Press 'h' for instructions.]"))
                            + 2 * soglitch;
                    my_putstring (Sexit);
                }
                else
                    promptlen = pr (_("[Press 'h' for instructions.]"));
                fflush (stdout);
            }
            else
                ringbell();
            break;
        }
        if (done) break;
    }
    putchar ('\r');
endsw:
    inwait = 0;
    notell++;
    return (retval);
}

static char ch;

/*
 * Execute a colon-prefixed command.
 * Returns <0 if not a command that should cause
 * more of the file to be printed.
 */

int colon (char *filename, int cmd, int nlines) {
        if (cmd == 0)
                ch = readch ();
        else
                ch = cmd;
        lastcolon = ch;
        switch (ch) {
        case 'f':
                kill_line ();
                if (!no_intty)
                        promptlen = xprintf (_("\"%s\" line %d"), fnames[fnum], Currline);
                else
                        promptlen = xprintf (_("[Not a file] line %d"), Currline);
                fflush (stdout);
                return (-1);
        case 'n':
                if (nlines == 0) {
                        if (fnum >= nfiles - 1)
                                end_it (0);
                        nlines++;
                }
                putchar ('\r');
                erasep (0);
                skipf (nlines);
                return (0);
        case 'p':
                if (no_intty) {
                        ringbell();
                        return (-1);
                }
                putchar ('\r');
                erasep (0);
                if (nlines == 0)
                        nlines++;
                skipf (-nlines);
                return (0);
        case '!':
                do_shell (filename);
                return (-1);
        case 'q':
        case 'Q':
                end_it (0);
        default:
                ringbell();
                return (-1);
        }
}

/*
** Read a decimal number from the terminal. Set cmd to the non-digit which
** terminates the number.
*/

int number(char *cmd)
{
        register int i;

        i = 0; ch = otty.c_cc[VKILL];
        for (;;) {
                ch = readch ();
                if (isdigit(ch))
                        i = i*10 + ch - '0';
                else if ((cc_t) ch == otty.c_cc[VKILL])
                        i = 0;
                else {
                        *cmd = ch;
                        break;
                }
        }
        return (i);
}

void do_shell (char *filename)
{
        char cmdbuf[200];
        int rc;
        char *expanded;

        kill_line ();
        pr ("!");
        fflush (stdout);
        promptlen = 1;
        if (lastp)
                pr (shell_line);
        else {
                ttyin (cmdbuf, sizeof(cmdbuf)-2, '!');
                expanded = 0;
                rc = expand (&expanded, cmdbuf);
                if (expanded) {
                        if (strlen(expanded) < sizeof(shell_line))
                                strcpy(shell_line, expanded);
                        else
                                rc = -1;
                        free(expanded);
                }
                if (rc < 0) {
                        errwrite(_("  Overflow\n"));
                        prompt (filename);
                        return;
                } else if (rc > 0) {
                        kill_line ();
                        promptlen = xprintf ("!%s", shell_line);
                }
        }
        fflush (stdout);
        errwrite("\n");
        promptlen = 0;
        shellp = 1;
        execute (filename, shell, shell, "-c", shell_line, 0);
}

/*
** Search for nth ocurrence of regular expression contained in buf in the file
*/

void search(char buf[], FILE *file, register int n)
{
    long startline = Ftell (file);
    register long line1 = startline;
    register long line2 = startline;
    register long line3 = startline;
    register int lncount;
    int saveln, rv;
    char *s;

    context.line = saveln = Currline;
    context.chrctr = startline;
    lncount = 0;
    if ((s = re_comp (buf)) != 0)
        error (s);
    while (!feof (file)) {
        line3 = line2;
        line2 = line1;
        line1 = Ftell (file);
        rdline (file);
        lncount++;
        if ((rv = re_exec (Line)) == 1) {
                if (--n == 0) {
                    if (lncount > 3 || (lncount > 1 && no_intty))
                    {
                        pr ("\n");
                        if (clreol)
                            cleareol ();
                        pr(_("...skipping\n"));
                    }
                    if (!no_intty) {
                        Currline -= (lncount >= 3 ? 3 : lncount);
                        Fseek (file, line3);
                        if (noscroll) {
                            if (clreol) {
                                home ();
                                cleareol ();
                            }
                            else
                                doclear ();
                        }
                    }
                    else {
                        kill_line ();
                        if (noscroll) {
                            if (clreol) {
                                home ();
                                cleareol ();
                            }
                            else
                                doclear ();
                        }
                        pr (Line);
                        putchar ('\n');
                    }
                    break;
                }
        } else if (rv == -1)
            error (_("Regular expression botch"));
    }
    if (feof (file)) {
        if (!no_intty) {
#ifndef __linux__
                                /* No longer in libc 4.5.8. . . */
            file->_flags &= ~STDIO_S_EOF_SEEN; /* why doesn't fseek do this ??!!??! */
#endif
            Currline = saveln;
            Fseek (file, startline);
        }
        else {
            pr (_("\nPattern not found\n"));
            end_it (0);
        }
        error (_("Pattern not found"));
    }
}

/*VARARGS2*/
void execute (char * filename, char * cmd, ...)
{
        int id;
        int n;
        va_list argp;
        char * arg;
        char ** args;
        int argcount;

        fflush (stdout);
        reset_tty ();
        for (n = 10; (id = fork ()) < 0 && n > 0; n--)
            sleep (5);
        if (id == 0) {
            if (!isatty(0)) {
                close(0);
                open("/dev/tty", 0);
            }

            va_start(argp, cmd);
            arg = va_arg(argp, char *);
            argcount = 0;
            while (arg) {
                argcount++;
                arg = va_arg(argp, char *);
            }
            va_end(argp);

            args = alloca(sizeof(char *) * (argcount + 1));
            args[argcount] = NULL;
            
            va_start(argp, cmd);
            arg = va_arg(argp, char *);
            argcount = 0;
            while (arg) {
                args[argcount] = arg;
                argcount++;
                arg = va_arg(argp, char *);
            }
            va_end(argp);
        
            execvp (cmd, args);
            errwrite(_("exec failed\n"));
            exit (1);
        }
        if (id > 0) {
            signal (SIGINT, SIG_IGN);
            signal (SIGQUIT, SIG_IGN);
            if (catch_susp)
                signal(SIGTSTP, SIG_DFL);
            while (wait(0) > 0);
            signal (SIGINT, end_it);
            signal (SIGQUIT, onquit);
            if (catch_susp)
                signal(SIGTSTP, onsusp);
        } else
            errwrite(_("can't fork\n"));
        set_tty ();
        pr ("------------------------\n");
        prompt (filename);
}
/*
** Skip n lines in the file f
*/

void skiplns (register int n, register FILE *f)
{
    register int c;

    while (n > 0) {
        while ((c = Getc (f)) != '\n')
            if (c == EOF)
                return;
            n--;
            Currline++;
    }
}

/*
** Skip nskip files in the file list (from the command line). Nskip may be
** negative.
*/

void skipf (register int nskip)
{
    if (nskip == 0) return;
    if (nskip > 0) {
        if (fnum + nskip > nfiles - 1)
            nskip = nfiles - fnum - 1;
    }
    else if (within)
        ++fnum;
    fnum += nskip;
    if (fnum < 0)
        fnum = 0;
    pr (_("\n...Skipping "));
    pr ("\n");
    if (clreol)
        cleareol ();
    if (nskip > 0)
            pr (_("...Skipping to file "));
    else
            pr (_("...Skipping back to file "));
    pr (fnames[fnum]);
    pr ("\n");
    if (clreol)
        cleareol ();
    pr ("\n");
    --fnum;
}

/*----------------------------- Terminal I/O -------------------------------*/

void initterm()
{
    int         ret;
    char        *padstr;
    char        *term;
    struct winsize win;

#ifdef do_SIGTTOU
retry:
#endif
    no_tty = tcgetattr(fileno(stdout), &otty);
    if (!no_tty) {      
        docrterase = (otty.c_cc[VERASE] != 255);
        docrtkill =  (otty.c_cc[VKILL] != 255);
#ifdef do_SIGTTOU
        {
            int tgrp;
            /*
             * Wait until we're in the foreground before we save the
             * the terminal modes.
             */
            if ((tgrp = tcgetpgrp(fileno(stdout))) < 0) {
                perror("tcgetpgrp");
                exit(1);
            }
            if (tgrp != getpgrp(0)) {
                kill(0, SIGTTOU);
                goto retry;
            }
        }
#endif
        if ((term = getenv("TERM")) == 0) {
            dumb++; ul_opt = 0;
        }
        my_setupterm(term, 1, &ret);
        if (ret <= 0) {
            dumb++; ul_opt = 0;
        }
        else {
#ifdef TIOCGWINSZ
            if (ioctl(fileno(stdout), TIOCGWINSZ, &win) < 0) {
#endif
                Lpp = my_tgetnum("li","lines");
                Mcol = my_tgetnum("co","cols");
#ifdef TIOCGWINSZ
            } else {
                if ((Lpp = win.ws_row) == 0)
                    Lpp = my_tgetnum("li","lines");
                if ((Mcol = win.ws_col) == 0)
                    Mcol = my_tgetnum("co","cols");
            }
#endif
            if ((Lpp <= 0) || my_tgetflag("hc","hc")) {
                hard++; /* Hard copy terminal */
                Lpp = 24;
            }

            if (my_tgetflag("xn","xenl"))
                eatnl++; /* Eat newline at last column + 1; dec, concept */
            if (Mcol <= 0)
                Mcol = 80;

            if (tailequ (fnames[0], "page"))
                noscroll++;
            Wrap = my_tgetflag("am","am");
            bad_so = my_tgetflag ("xs","xhp");
            eraseln = my_tgetstr("ce","el");
            Clear = my_tgetstr("cl","clear");
            Senter = my_tgetstr("so","smso");
            Sexit = my_tgetstr("se","rmso");
            if ((soglitch = my_tgetnum("sg","xmc")) < 0)
                soglitch = 0;

            /*
             *  Set up for underlining:  some terminals don't need it;
             *  others have start/stop sequences, still others have an
             *  underline char sequence which is assumed to move the
             *  cursor forward one character.  If underline sequence
             *  isn't available, settle for standout sequence.
             */

            if (my_tgetflag("ul","ul") || my_tgetflag("os","os"))
                ul_opt = 0;
            if ((chUL = my_tgetstr("uc","uc")) == NULL )
                chUL = "";
            if (((ULenter = my_tgetstr("us","smul")) == NULL ||
                 (ULexit = my_tgetstr("ue","rmul")) == NULL) && !*chUL) {
                if ((ULenter = Senter) == NULL || (ULexit = Sexit) == NULL) {
                        ULenter = "";
                        ULexit = "";
                } else
                        ulglitch = soglitch;
            } else {
                ulglitch = 0;
            }

            if ((padstr = my_tgetstr("pc","pad")) != NULL)
                PC = *padstr;
            Home = my_tgetstr("ho","home");
            if (Home == 0 || *Home == '\0') {
                if ((cursorm = my_tgetstr("cm","cup")) != NULL) {
                    const char *t = (const char *)my_tgoto(cursorm, 0, 0);
                    xstrncpy(cursorhome, t, sizeof(cursorhome));
                    Home = cursorhome;
                }
            }
            EodClr = my_tgetstr("cd","ed");
            if ((chBS = my_tgetstr("le","cub1")) == NULL)
                chBS = "\b";

        }
        if ((shell = getenv("SHELL")) == NULL)
            shell = "/bin/sh";
    }
    no_intty = tcgetattr(fileno(stdin), &otty);
    tcgetattr(fileno(stderr), &otty);
    savetty0 = otty;
    slow_tty = (otty.c_cflag & CBAUD) < B1200;
    hardtabs = (otty.c_oflag & TABDLY) != XTABS;
    if (!no_tty) {
        otty.c_lflag &= ~(ICANON|ECHO);
        otty.c_cc[VMIN] = 1;
        otty.c_cc[VTIME] = 0;
    }
}

int readch () {
        unsigned char c;

        errno = 0;
        if (read (fileno(stderr), &c, 1) <= 0) {
                if (errno != EINTR)
                        end_it(0);
                else
                        c = otty.c_cc[VKILL];
        }
        return (c);
}

static char *BS = "\b";
static char *BSB = "\b \b";
static char *CARAT = "^";
#define ERASEONECOLUMN \
    if (docrterase) \
        errwrite(BSB); \
    else \
        errwrite(BS);

void ttyin (unsigned char buf[], register int nmax, char pchar) {
    unsigned char *sp;
    int c;
    int slash = 0;
    int maxlen;

    sp = buf;
    maxlen = 0;
    while (sp - buf < nmax) {
        if (promptlen > maxlen) maxlen = promptlen;
        c = readch ();
        if (c == '\\') {
            slash++;
        }
        else if (((cc_t) c == otty.c_cc[VERASE]) && !slash) {
            if (sp > buf) {
#ifdef ENABLE_WIDECHAR
                if (MB_CUR_MAX > 1)
                  {
                    wchar_t wc;
                    size_t pos = 0, mblength;
                    mbstate_t state, state_bak;

                    memset (&state, '\0', sizeof (mbstate_t));

                    while (1) {
                         state_bak = state;
                         mblength = mbrtowc (&wc, buf + pos, sp - buf, &state);

                         state = (mblength == (size_t)-2
                                 || mblength == (size_t)-1) ? state_bak : state;
                         mblength = (mblength == (size_t)-2
                                     || mblength == (size_t)-1
                                     || mblength == 0) ? 1 : mblength;

                         if (buf + pos + mblength >= sp)
                         break;

                         pos += mblength;
                    }

                    if (mblength == 1) {
                      ERASEONECOLUMN
                    }
                    else {
                        int wc_width;
                        wc_width = wcwidth (wc);
                        wc_width = (wc_width < 1) ? 1 : wc_width;
                        while (wc_width--) {
                            ERASEONECOLUMN
                        }
                    }

                    while (mblength--) {
                        --promptlen;
                        --sp;
                    }
                  }
                else
#endif
                  {
                    --promptlen;
                    ERASEONECOLUMN
                    --sp;
                  }

                if ((*sp < ' ' && *sp != '\n') || *sp == RUBOUT) {
                    --promptlen;
                    ERASEONECOLUMN
                }
                continue;
            }
            else {
                if (!eraseln) promptlen = maxlen;
                siglongjmp (restore, 1);
            }
        }
        else if (((cc_t) c == otty.c_cc[VKILL]) && !slash) {
            if (hard) {
                show (c);
                putchar ('\n');
                putchar (pchar);
            }
            else {
                putchar ('\r');
                putchar (pchar);
                if (eraseln)
                    erasep (1);
                else if (docrtkill)
                    while (promptlen-- > 1)
                        errwrite(BSB);
                promptlen = 1;
            }
            sp = buf;
            fflush (stdout);
            continue;
        }
        if (slash && ((cc_t) c == otty.c_cc[VKILL]
                   || (cc_t) c == otty.c_cc[VERASE])) {
            ERASEONECOLUMN
            --sp;
        }
        if (c != '\\')
            slash = 0;
        *sp++ = c;
        if ((c < ' ' && c != '\n' && c != ESC) || c == RUBOUT) {
            c += (c == RUBOUT) ? -0100 : 0100;
            errwrite(CARAT);
            promptlen++;
        }
        if (c != '\n' && c != ESC) {
            char cbuf = c;
            errwrite1(&cbuf);
            promptlen++;
        }
        else
            break;
    }
    *--sp = '\0';
    if (!eraseln) promptlen = maxlen;
    if (sp - buf >= nmax - 1)
        error (_("Line too long"));
}

/* return: 0 - unchanged, 1 - changed, -1 - overflow (unchanged) */
int expand (char **outbuf, char *inbuf) {
    char *inpstr;
    char *outstr;
    char c;
    char *temp;
    int changed = 0;
    int tempsz, xtra, offset;

    xtra = strlen (fnames[fnum]) + strlen (shell_line) + 1;
    tempsz = 200 + xtra;
    temp = malloc(tempsz);
    if (!temp) {
            error (_("Out of memory"));
            return -1;
    }
    inpstr = inbuf;
    outstr = temp;
    while ((c = *inpstr++) != '\0'){
        offset = outstr-temp;
        if (tempsz-offset-1 < xtra) {
                tempsz += 200 + xtra;
                temp = realloc(temp, tempsz);
                if (!temp) {
                        error (_("Out of memory"));
                        return -1;
                }
                outstr = temp + offset;
        }
        switch (c) {
        case '%':
            if (!no_intty) {
                strcpy (outstr, fnames[fnum]);
                outstr += strlen (fnames[fnum]);
                changed++;
            } else
                *outstr++ = c;
            break;
        case '!':
            if (!shellp)
                error (_("No previous command to substitute for"));
            strcpy (outstr, shell_line);
            outstr += strlen (shell_line);
            changed++;
            break;
        case '\\':
            if (*inpstr == '%' || *inpstr == '!') {
                *outstr++ = *inpstr++;
                break;
            }
        default:
            *outstr++ = c;
        }
    }
    *outstr++ = '\0';
    *outbuf = temp;
    return (changed);
}

void show (char c) {
    char cbuf;

    if ((c < ' ' && c != '\n' && c != ESC) || c == RUBOUT) {
        c += (c == RUBOUT) ? -0100 : 0100;
        errwrite(CARAT);
        promptlen++;
    }
    cbuf = c;
    errwrite1(&cbuf);
    promptlen++;
}

void errwrite (char *txt)
{
    write (fileno(stderr), txt, strlen(txt));
}

void errwrite1 (char *sym)
{
    write (fileno(stderr), sym, 1);
}

void error (char *mess)
{
    if (clreol)
        cleareol ();
    else
        kill_line ();
    promptlen += strlen (mess);
    if (Senter && Sexit) {
        my_putstring (Senter);
        pr(mess);
        my_putstring (Sexit);
    }
    else
        pr (mess);
    fflush(stdout);
    errors++;
    siglongjmp (restore, 1);
}


void set_tty () {
        otty.c_lflag &= ~(ICANON|ECHO);
        otty.c_cc[VMIN] = 1;    /* read at least 1 char */
        otty.c_cc[VTIME] = 0;   /* no timeout */
        stty(fileno(stderr), &otty);
}

static int
ourputch(int c) {
    return putc(c, stdout);
}

void
reset_tty () {
    if (no_tty)
        return;
    if (pstate) {
        tputs(ULexit, 1, ourputch);
        fflush(stdout);
        pstate = 0;
    }
    otty.c_lflag |= ICANON|ECHO;
    otty.c_cc[VMIN] = savetty0.c_cc[VMIN];
    otty.c_cc[VTIME] = savetty0.c_cc[VTIME];
    stty(fileno(stderr), &savetty0);
}

void rdline (register FILE *f)
{
    register int  c;
    register char *p;

    p = Line;
    while ((c = Getc (f)) != '\n' && c != EOF && p - Line < LINSIZ - 1)
        *p++ = c;
    if (c == '\n')
        Currline++;
    *p = '\0';
}

/* Come here when we get a suspend signal from the terminal */

void onsusp (int dummy) {
    sigset_t signals, oldmask;

    /* ignore SIGTTOU so we don't get stopped if csh grabs the tty */
    signal(SIGTTOU, SIG_IGN);
    reset_tty ();
    fflush (stdout);
    signal(SIGTTOU, SIG_DFL);
    /* Send the TSTP signal to suspend our process group */
    signal(SIGTSTP, SIG_DFL);

    /* unblock SIGTSTP or we won't be able to suspend ourself */
    sigemptyset(&signals);
    sigaddset(&signals, SIGTSTP);
    sigprocmask(SIG_UNBLOCK, &signals, &oldmask);

    kill (0, SIGTSTP);
    /* Pause for station break */

    sigprocmask(SIG_SETMASK, &oldmask, NULL);

    /* We're back */
    signal (SIGTSTP, onsusp);
    set_tty ();
    if (inwait)
            siglongjmp (restore, 1);
}