path: root/Src/utils.c

/*
 * utils.c - miscellaneous utilities
 *
 * This file is part of zsh, the Z shell.
 *
 * Copyright (c) 1992-1997 Paul Falstad
 * All rights reserved.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and to distribute modified versions of this software for any
 * purpose, provided that the above copyright notice and the following
 * two paragraphs appear in all copies of this software.
 *
 * In no event shall Paul Falstad or the Zsh Development Group be liable
 * to any party for direct, indirect, special, incidental, or consequential
 * damages arising out of the use of this software and its documentation,
 * even if Paul Falstad and the Zsh Development Group have been advised of
 * the possibility of such damage.
 *
 * Paul Falstad and the Zsh Development Group specifically disclaim any
 * warranties, including, but not limited to, the implied warranties of
 * merchantability and fitness for a particular purpose.  The software
 * provided hereunder is on an "as is" basis, and Paul Falstad and the
 * Zsh Development Group have no obligation to provide maintenance,
 * support, updates, enhancements, or modifications.
 *
 */

#include "zsh.mdh"
#include "utils.pro"

/* name of script being sourced */

/**/
char *scriptname;

/* Print an error */
 
/**/
mod_export void
zerr(const char *fmt, const char *str, int num)
{
    if (errflag || noerrs) {
	if (noerrs < 2)
	    errflag = 1;
	return;
    }
    zwarn(fmt, str, num);
    errflag = 1;
}

/**/
mod_export void
zerrnam(const char *cmd, const char *fmt, const char *str, int num)
{
    if (errflag || noerrs)
	return;

    zwarnnam(cmd, fmt, str, num);
    errflag = 1;
}

/**/
mod_export void
zwarn(const char *fmt, const char *str, int num)
{
    if (errflag || noerrs)
	return;
    trashzle();
    /*
     * scriptname is set when sourcing scripts, so that we get the
     * correct name instead of the generic name of whatever
     * program/script is running.  It's also set in shell functions,
     * so test locallevel, too.
     */
    nicezputs((isset(SHINSTDIN) && !locallevel) ? "zsh" :
	      scriptname ? scriptname : argzero, stderr);
    fputc((unsigned char)':', stderr);
    zerrmsg(fmt, str, num);
}

/**/
mod_export void
zwarnnam(const char *cmd, const char *fmt, const char *str, int num)
{
    if (errflag || noerrs)
	return;
    trashzle();
    if (unset(SHINSTDIN) || locallevel) {
	nicezputs(scriptname ? scriptname : argzero, stderr);
	fputc((unsigned char)':', stderr);
    }
    if (cmd) {
	nicezputs(cmd, stderr);
	fputc((unsigned char)':', stderr);
    }
    zerrmsg(fmt, str, num);
}

/**/
void
zerrmsg(const char *fmt, const char *str, int num)
{
    if ((unset(SHINSTDIN) || locallevel) && lineno)
	fprintf(stderr, "%ld: ", (long)lineno);
    else
	fputc((unsigned char)' ', stderr);

    while (*fmt)
	if (*fmt == '%') {
	    fmt++;
	    switch (*fmt++) {
	    case 's':
		nicezputs(str, stderr);
		break;
	    case 'l': {
		char *s;
		num = metalen(str, num);
		s = zhalloc(num + 1);
		memcpy(s, str, num);
		s[num] = '\0';
		nicezputs(s, stderr);
		break;
	    }
	    case 'd':
		fprintf(stderr, "%d", num);
		break;
	    case '%':
		putc('%', stderr);
		break;
	    case 'c':
		fputs(nicechar(num), stderr);
		break;
	    case 'e':
		/* print the corresponding message for this errno */
		if (num == EINTR) {
		    fputs("interrupt\n", stderr);
		    errflag = 1;
		    return;
		}
		/* If the message is not about I/O problems, it looks better *
		 * if we uncapitalize the first letter of the message        */
		if (num == EIO)
		    fputs(strerror(num), stderr);
		else {
		    char *errmsg = strerror(num);
		    fputc(tulower(errmsg[0]), stderr);
		    fputs(errmsg + 1, stderr);
		}
		break;
	    }
	} else {
	    putc(*fmt == Meta ? *++fmt ^ 32 : *fmt, stderr);
	    fmt++;
	}
    putc('\n', stderr);
    fflush(stderr);
}

/* Output a single character, for the termcap routines.     *
 * This is used instead of putchar since it can be a macro. */

/**/
int
putraw(int c)
{
    putc(c, stdout);
    return 0;
}

/* Output a single character, for the termcap routines. */

/**/
mod_export int
putshout(int c)
{
    putc(c, shout);
    return 0;
}

/* Turn a character into a visible representation thereof.  The visible *
 * string is put together in a static buffer, and this function returns *
 * a pointer to it.  Printable characters stand for themselves, DEL is  *
 * represented as "^?", newline and tab are represented as "\n" and     *
 * "\t", and normal control characters are represented in "^C" form.    *
 * Characters with bit 7 set, if unprintable, are represented as "\M-"  *
 * followed by the visible representation of the character with bit 7   *
 * stripped off.  Tokens are interpreted, rather than being treated as  *
 * literal characters.                                                  */

/**/
mod_export char *
nicechar(int c)
{
    static char buf[6];
    char *s = buf;
    c &= 0xff;
    if (isprint(c))
	goto done;
    if (c & 0x80) {
	if (isset(PRINTEIGHTBIT))
	    goto done;
	*s++ = '\\';
	*s++ = 'M';
	*s++ = '-';
	c &= 0x7f;
	if(isprint(c))
	    goto done;
    }
    if (c == 0x7f) {
	*s++ = '^';
	c = '?';
    } else if (c == '\n') {
	*s++ = '\\';
	c = 'n';
    } else if (c == '\t') {
	*s++ = '\\';
	c = 't';
    } else if (c < 0x20) {
	*s++ = '^';
	c += 0x40;
    }
    done:
    *s++ = c;
    *s = 0;
    return buf;
}

/* Output a string's visible representation. */

#if 0 /**/
void
nicefputs(char *s, FILE *f)
{
    for (; *s; s++)
	fputs(nicechar(STOUC(*s)), f);
}
#endif

/* Return the length of the visible representation of a string. */

/**/
size_t
nicestrlen(char *s)
{
    size_t l = 0;

    for (; *s; s++)
	l += strlen(nicechar(STOUC(*s)));
    return l;
}

/* get a symlink-free pathname for s relative to PWD */

/**/
char *
findpwd(char *s)
{
    char *t;

    if (*s == '/')
	return xsymlink(s);
    s = tricat((pwd[1]) ? pwd : "", "/", s);
    t = xsymlink(s);
    zsfree(s);
    return t;
}

/* Check whether a string contains the *
 * name of the present directory.      */

/**/
int
ispwd(char *s)
{
    struct stat sbuf, tbuf;

    if (stat(unmeta(s), &sbuf) == 0 && stat(".", &tbuf) == 0)
	if (sbuf.st_dev == tbuf.st_dev && sbuf.st_ino == tbuf.st_ino)
	    return 1;
    return 0;
}

static char xbuf[PATH_MAX*2];

/**/
static char **
slashsplit(char *s)
{
    char *t, **r, **q;
    int t0;

    if (!*s)
	return (char **) zcalloc(sizeof(char **));

    for (t = s, t0 = 0; *t; t++)
	if (*t == '/')
	    t0++;
    q = r = (char **) zalloc(sizeof(char **) * (t0 + 2));

    while ((t = strchr(s, '/'))) {
	*q++ = ztrduppfx(s, t - s);
	while (*t == '/')
	    t++;
	if (!*t) {
	    *q = NULL;
	    return r;
	}
	s = t;
    }
    *q++ = ztrdup(s);
    *q = NULL;
    return r;
}

/* expands symlinks and .. or . expressions */
/* if flag = 0, only expand .. and . expressions */

/**/
static int
xsymlinks(char *s)
{
    char **pp, **opp;
    char xbuf2[PATH_MAX*2], xbuf3[PATH_MAX*2];
    int t0, ret = 0;

    opp = pp = slashsplit(s);
    for (; *pp; pp++) {
	if (!strcmp(*pp, ".")) {
	    zsfree(*pp);
	    continue;
	}
	if (!strcmp(*pp, "..")) {
	    char *p;

	    zsfree(*pp);
	    if (!strcmp(xbuf, "/"))
		continue;
	    p = xbuf + strlen(xbuf);
	    while (*--p != '/');
	    *p = '\0';
	    continue;
	}
	sprintf(xbuf2, "%s/%s", xbuf, *pp);
	t0 = readlink(unmeta(xbuf2), xbuf3, PATH_MAX);
	if (t0 == -1) {
	    strcat(xbuf, "/");
	    strcat(xbuf, *pp);
	    zsfree(*pp);
	} else {
	    ret = 1;
	    metafy(xbuf3, t0, META_NOALLOC);
	    if (*xbuf3 == '/') {
		strcpy(xbuf, "");
		xsymlinks(xbuf3 + 1);
	    } else
		xsymlinks(xbuf3);
	    zsfree(*pp);
	}
    }
    free(opp);
    return ret;
}

/*
 * expand symlinks in s, and remove other weird things:
 * note that this always expands symlinks.
 */

/**/
char *
xsymlink(char *s)
{
    if (*s != '/')
	return NULL;
    *xbuf = '\0';
    xsymlinks(s + 1);
    if (!*xbuf)
	return ztrdup("/");
    return ztrdup(xbuf);
}

/**/
void
print_if_link(char *s)
{
    if (*s == '/') {
	*xbuf = '\0';
	if (xsymlinks(s + 1))
	    printf(" -> "), zputs(*xbuf ? xbuf : "/", stdout);
    }
}

/* print a directory */

/**/
void
fprintdir(char *s, FILE *f)
{
    Nameddir d = finddir(s);

    if (!d)
	fputs(unmeta(s), f);
    else {
	putc('~', f);
	fputs(unmeta(d->nam), f);
	fputs(unmeta(s + strlen(d->dir)), f);
    }
}

/* Returns the current username.  It caches the username *
 * and uid to try to avoid requerying the password files *
 * or NIS/NIS+ database.                                 */

/**/
uid_t cached_uid;
/**/
char *cached_username;

/**/
char *
get_username(void)
{
#ifdef HAVE_GETPWUID
    struct passwd *pswd;
    uid_t current_uid;
 
    current_uid = getuid();
    if (current_uid != cached_uid) {
	cached_uid = current_uid;
	zsfree(cached_username);
	if ((pswd = getpwuid(current_uid)))
	    cached_username = ztrdup(pswd->pw_name);
	else
	    cached_username = ztrdup("");
    }
#else /* !HAVE_GETPWUID */
    cached_uid = getuid();
#endif /* !HAVE_GETPWUID */
    return cached_username;
}

/* static variables needed by finddir(). */

static char *finddir_full;
static Nameddir finddir_last;
static int finddir_best;

/* ScanFunc used by finddir(). */

/**/
static void
finddir_scan(HashNode hn, int flags)
{
    Nameddir nd = (Nameddir) hn;

    if(nd->diff > finddir_best && !dircmp(nd->dir, finddir_full)
       && !(nd->flags & ND_NOABBREV)) {
	finddir_last=nd;
	finddir_best=nd->diff;
    }
}

/* See if a path has a named directory as its prefix. *
 * If passed a NULL argument, it will invalidate any  *
 * cached information.                                */

/**/
Nameddir
finddir(char *s)
{
    static struct nameddir homenode = { NULL, "", 0, NULL, 0 };
    static int ffsz;

    /* Invalidate directory cache if argument is NULL.  This is called *
     * whenever a node is added to or removed from the hash table, and *
     * whenever the value of $HOME changes.  (On startup, too.)        */
    if (!s) {
	homenode.dir = home;
	homenode.diff = strlen(home);
	if(homenode.diff==1)
	    homenode.diff = 0;
	if(!finddir_full)
	    finddir_full = zalloc(ffsz = PATH_MAX);
	finddir_full[0] = 0;
	return finddir_last = NULL;
    }

    if(!strcmp(s, finddir_full) && *finddir_full)
	return finddir_last;

    if(strlen(s) >= ffsz) {
	free(finddir_full);
	finddir_full = zalloc(ffsz = strlen(s) * 2);
    }
    strcpy(finddir_full, s);
    finddir_best=0;
    finddir_last=NULL;
    finddir_scan((HashNode)&homenode, 0);
    scanhashtable(nameddirtab, 0, 0, 0, finddir_scan, 0);
    return finddir_last;
}

/* add a named directory */

/**/
mod_export void
adduserdir(char *s, char *t, int flags, int always)
{
    Nameddir nd;

    /* We don't maintain a hash table in non-interactive shells. */
    if (!interact)
	return;

    /* The ND_USERNAME flag means that this possible hash table *
     * entry is derived from a passwd entry.  Such entries are  *
     * subordinate to explicitly generated entries.             */
    if ((flags & ND_USERNAME) && nameddirtab->getnode2(nameddirtab, s))
	return;

    /* Normal parameter assignments generate calls to this function, *
     * with always==0.  Unless the AUTO_NAME_DIRS option is set, we  *
     * don't let such assignments actually create directory names.   *
     * Instead, a reference to the parameter as a directory name can *
     * cause the actual creation of the hash table entry.            */
    if (!always && unset(AUTONAMEDIRS) &&
	    !nameddirtab->getnode2(nameddirtab, s))
	return;

    if (!t || *t != '/' || strlen(t) >= PATH_MAX) {
	/* We can't use this value as a directory, so simply remove *
	 * the corresponding entry in the hash table, if any.       */
	HashNode hn = nameddirtab->removenode(nameddirtab, s);

	if(hn)
	    nameddirtab->freenode(hn);
	return;
    }

    /* add the name */
    nd = (Nameddir) zcalloc(sizeof *nd);
    nd->flags = flags;
    nd->dir = ztrdup(t);
    /* The variables PWD and OLDPWD are not to be displayed as ~PWD etc. */
    if (!strcmp(s, "PWD") || !strcmp(s, "OLDPWD"))
	nd->flags |= ND_NOABBREV;
    nameddirtab->addnode(nameddirtab, ztrdup(s), nd);
}

/* Get a named directory: this function can cause a directory name *
 * to be added to the hash table, if it isn't there already.       */

/**/
char *
getnameddir(char *name)
{
    Param pm;
    char *str;
    Nameddir nd;

    /* Check if it is already in the named directory table */
    if ((nd = (Nameddir) nameddirtab->getnode(nameddirtab, name)))
	return dupstring(nd->dir);

    /* Check if there is a scalar parameter with this name whose value *
     * begins with a `/'.  If there is, add it to the hash table and   *
     * return the new value.                                           */
    if ((pm = (Param) paramtab->getnode(paramtab, name)) &&
	    (PM_TYPE(pm->flags) == PM_SCALAR) &&
	    (str = getsparam(name)) && *str == '/') {
	adduserdir(name, str, 0, 1);
	return str;
    }

#ifdef HAVE_GETPWNAM
    {
	/* Retrieve an entry from the password table/database for this user. */
	struct passwd *pw;
	if ((pw = getpwnam(name))) {
	    char *dir = isset(CHASELINKS) ? xsymlink(pw->pw_dir)
		: ztrdup(pw->pw_dir);
	    adduserdir(name, dir, ND_USERNAME, 1);
	    str = dupstring(dir);
	    zsfree(dir);
	    return str;
	}
    }
#endif /* HAVE_GETPWNAM */

    /* There are no more possible sources of directory names, so give up. */
    return NULL;
}

/**/
static int
dircmp(char *s, char *t)
{
    if (s) {
	for (; *s == *t; s++, t++)
	    if (!*s)
		return 0;
	if (!*s && *t == '/')
	    return 0;
    }
    return 1;
}

/* extra functions to call before displaying the prompt */

/**/
mod_export LinkList prepromptfns;

/* the last time we checked mail */
 
/**/
time_t lastmailcheck;
 
/* the last time we checked the people in the WATCH variable */
 
/**/
time_t lastwatch;

/* do pre-prompt stuff */

/**/
void
preprompt(void)
{
    static time_t lastperiodic;
    LinkNode ln;
    List list;
    int period = getiparam("PERIOD");
    int mailcheck = getiparam("MAILCHECK");

    /* If NOTIFY is not set, then check for completed *
     * jobs before we print the prompt.               */
    if (unset(NOTIFY))
	scanjobs();
    if (errflag)
	return;

    /* If a shell function named "precmd" exists, *
     * then execute it.                           */
    if ((list = getshfunc("precmd")) != &dummy_list) {
	int osc = sfcontext;

	sfcontext = SFC_HOOK;
	doshfunc("precmd", list, NULL, 0, 1);
	sfcontext = osc;
    }
    if (errflag)
	return;

    /* If 1) the parameter PERIOD exists, 2) the shell function     *
     * "periodic" exists, 3) it's been greater than PERIOD since we *
     * executed "periodic", then execute it now.                    */
    if (period && (time(NULL) > lastperiodic + period) &&
	(list = getshfunc("periodic")) != &dummy_list) {
	int osc = sfcontext;

	sfcontext = SFC_HOOK;
	doshfunc("periodic", list, NULL, 0, 1);
	sfcontext = osc;
	lastperiodic = time(NULL);
    }
    if (errflag)
	return;

    /* If WATCH is set, then check for the *
     * specified login/logout events.      */
    if (watch) {
	if ((int) difftime(time(NULL), lastwatch) > getiparam("LOGCHECK")) {
	    dowatch();
	    lastwatch = time(NULL);
	}
    }
    if (errflag)
	return;

    /* Check mail */
    if (mailcheck && (int) difftime(time(NULL), lastmailcheck) > mailcheck) {
	char *mailfile;

	if (mailpath && *mailpath && **mailpath)
	    checkmailpath(mailpath);
	else if ((mailfile = getsparam("MAIL")) && *mailfile) {
	    char *x[2];

	    x[0] = mailfile;
	    x[1] = NULL;
	    checkmailpath(x);
	}
	lastmailcheck = time(NULL);
    }

    /* Some people have claimed that C performs type    *
     * checking, but they were later found to be lying. */
    for(ln = firstnode(prepromptfns); ln; ln = nextnode(ln))
	(**(void (**) _((void)))getdata(ln))();
}

/**/
static void
checkmailpath(char **s)
{
    struct stat st;
    char *v, *u, c;

    while (*s) {
	for (v = *s; *v && *v != '?'; v++);
	c = *v;
	*v = '\0';
	if (c != '?')
	    u = NULL;
	else
	    u = v + 1;
	if (**s == 0) {
	    *v = c;
	    zerr("empty MAILPATH component: %s", *s, 0);
#ifndef MAILDIR_SUPPORT
	} else if (stat(unmeta(*s), &st) == -1) {
#else
	} else if (mailstat(unmeta(*s), &st) == -1) {
#endif
	    if (errno != ENOENT)
		zerr("%e: %s", *s, errno);
	} else if (S_ISDIR(st.st_mode)) {
	    LinkList l;
	    DIR *lock = opendir(unmeta(*s));
	    char buf[PATH_MAX * 2], **arr, **ap;
	    int ct = 1;

	    if (lock) {
		char *fn;
		HEAPALLOC {
		    pushheap();
		    l = newlinklist();
		    while ((fn = zreaddir(lock, 1)) && !errflag) {
			if (u)
			    sprintf(buf, "%s/%s?%s", *s, fn, u);
			else
			    sprintf(buf, "%s/%s", *s, fn);
			addlinknode(l, dupstring(buf));
			ct++;
		    }
		    closedir(lock);
		    ap = arr = (char **) alloc(ct * sizeof(char *));

		    while ((*ap++ = (char *)ugetnode(l)));
		    checkmailpath(arr);
		    popheap();
		} LASTALLOC;
	    }
	} else {
	    if (st.st_size && st.st_atime <= st.st_mtime &&
		st.st_mtime > lastmailcheck) {
		if (!u) {
		    fprintf(shout, "You have new mail.\n");
		    fflush(shout);
		} else {
		    VARARR(char, usav, underscoreused);

		    memcpy(usav, underscore, underscoreused);

		    setunderscore(*s);
		    HEAPALLOC {
			u = dupstring(u);
			if (! parsestr(u)) {
			    singsub(&u);
			    zputs(u, shout);
			    fputc('\n', shout);
			    fflush(shout);
			}
		    } LASTALLOC;
		    setunderscore(usav);
		}
	    }
	    if (isset(MAILWARNING) && st.st_atime > st.st_mtime &&
		st.st_atime > lastmailcheck && st.st_size) {
		fprintf(shout, "The mail in %s has been read.\n", unmeta(*s));
		fflush(shout);
	    }
	}
	*v = c;
	s++;
    }
}

/* This prints the XTRACE prompt. */

/**/
void
printprompt4(void)
{
    if (prompt4) {
	int l;
	char *s = dupstring(prompt4);

	unmetafy(s, &l);
	s = unmetafy(promptexpand(metafy(s, l, META_NOALLOC), 0, NULL, NULL), &l);

	fprintf(stderr, "%s", s);
    }
}

/**/
mod_export void
freestr(void *a)
{
    zsfree(a);
}

/**/
void
gettyinfo(struct ttyinfo *ti)
{
    if (SHTTY != -1) {
#ifdef HAVE_TERMIOS_H
# ifdef HAVE_TCGETATTR
	if (tcgetattr(SHTTY, &ti->tio) == -1)
# else
	if (ioctl(SHTTY, TCGETS, &ti->tio) == -1)
# endif
	    zerr("bad tcgets: %e", NULL, errno);
#else
# ifdef HAVE_TERMIO_H
	ioctl(SHTTY, TCGETA, &ti->tio);
# else
	ioctl(SHTTY, TIOCGETP, &ti->sgttyb);
	ioctl(SHTTY, TIOCLGET, &ti->lmodes);
	ioctl(SHTTY, TIOCGETC, &ti->tchars);
	ioctl(SHTTY, TIOCGLTC, &ti->ltchars);
# endif
#endif
    }
}

/**/
mod_export void
settyinfo(struct ttyinfo *ti)
{
    if (SHTTY != -1) {
#ifdef HAVE_TERMIOS_H
# ifdef HAVE_TCGETATTR
#  ifndef TCSADRAIN
#   define TCSADRAIN 1	/* XXX Princeton's include files are screwed up */
#  endif
	tcsetattr(SHTTY, TCSADRAIN, &ti->tio);
    /* if (tcsetattr(SHTTY, TCSADRAIN, &ti->tio) == -1) */
# else
	ioctl(SHTTY, TCSETS, &ti->tio);
    /* if (ioctl(SHTTY, TCSETS, &ti->tio) == -1) */
# endif
	/*	zerr("settyinfo: %e",NULL,errno)*/ ;
#else
# ifdef HAVE_TERMIO_H
	ioctl(SHTTY, TCSETA, &ti->tio);
# else
	ioctl(SHTTY, TIOCSETN, &ti->sgttyb);
	ioctl(SHTTY, TIOCLSET, &ti->lmodes);
	ioctl(SHTTY, TIOCSETC, &ti->tchars);
	ioctl(SHTTY, TIOCSLTC, &ti->ltchars);
# endif
#endif
    }
}

/* the default tty state */
 
/**/
mod_export struct ttyinfo shttyinfo;

/* != 0 if we need to call resetvideo() */

/**/
mod_export int resetneeded;

#ifdef TIOCGWINSZ
/* window size changed */

/**/
mod_export int winchanged;
#endif

static int
adjustlines(int signalled)
{
    int oldlines = lines;

#ifdef TIOCGWINSZ
    if (signalled || lines <= 0)
	lines = shttyinfo.winsize.ws_row;
    else
	shttyinfo.winsize.ws_row = lines;
#endif /* TIOCGWINSZ */
    if (lines <= 0) {
	DPUTS(signalled, "BUG: Impossible TIOCGWINSZ rows");
	lines = tclines > 0 ? tclines : 24;
    }

    if (lines > 2)
	termflags &= ~TERM_SHORT;
    else
	termflags |= TERM_SHORT;

    return (lines != oldlines);
}

static int
adjustcolumns(int signalled)
{
    int oldcolumns = columns;

#ifdef TIOCGWINSZ
    if (signalled || columns <= 0)
	columns = shttyinfo.winsize.ws_col;
    else
	shttyinfo.winsize.ws_col = columns;
#endif /* TIOCGWINSZ */
    if (columns <= 0) {
	DPUTS(signalled, "BUG: Impossible TIOCGWINSZ cols");
	columns = tccolumns > 0 ? tccolumns : 80;
    }

    if (columns > 2)
	termflags &= ~TERM_NARROW;
    else
	termflags |= TERM_NARROW;

    return (columns != oldcolumns);
}

/* check the size of the window and adjust if necessary. *
 * The value of from:					 *
 *   0: called from update_job or setupvals		 *
 *   1: called from the SIGWINCH handler		 *
 *   2: called from the LINES parameter callback	 *
 *   3: called from the COLUMNS parameter callback	 */

/**/
void
adjustwinsize(int from)
{
    static int getwinsz = 1;
    int ttyrows = shttyinfo.winsize.ws_row;
    int ttycols = shttyinfo.winsize.ws_col;
    int resetzle = 0;

    if (getwinsz || from == 1) {
#ifdef TIOCGWINSZ
	if (SHTTY == -1)
	    return;
	if (ioctl(SHTTY, TIOCGWINSZ, (char *)&shttyinfo.winsize) == 0) {
	    resetzle = (ttyrows != shttyinfo.winsize.ws_row ||
			ttycols != shttyinfo.winsize.ws_col);
	    if (from == 0 && resetzle && ttyrows && ttycols)
		from = 1; /* Signal missed while a job owned the tty? */
	    ttyrows = shttyinfo.winsize.ws_row;
	    ttycols = shttyinfo.winsize.ws_col;
	} else {
	    /* Set to unknown on failure */
	    shttyinfo.winsize.ws_row = 0;
	    shttyinfo.winsize.ws_col = 0;
	    resetzle = 1;
	}
#else
	resetzle = from == 1;
#endif /* TIOCGWINSZ */
    } /* else
	 return; */

    switch (from) {
    case 0:
    case 1:
	getwinsz = 0;
	/* Calling setiparam() here calls this function recursively, but  *
	 * because we've already called adjustlines() and adjustcolumns() *
	 * here, recursive calls are no-ops unless a signal intervenes.   *
	 * The commented "else return;" above might be a safe shortcut,   *
	 * but I'm concerned about what happens on race conditions; e.g., *
	 * suppose the user resizes his xterm during `eval $(resize)'?    */
	if (adjustlines(from) && zgetenv("LINES"))
	    setiparam("LINES", lines);
	if (adjustcolumns(from) && zgetenv("COLUMNS"))
	    setiparam("COLUMNS", columns);
	getwinsz = 1;
	break;
    case 2:
	resetzle = adjustlines(0);
	break;
    case 3:
	resetzle = adjustcolumns(0);
	break;
    }

#ifdef TIOCGWINSZ
    if (interact && from >= 2 &&
	(shttyinfo.winsize.ws_row != ttyrows ||
	 shttyinfo.winsize.ws_col != ttycols)) {
	/* shttyinfo.winsize is already set up correctly */
	ioctl(SHTTY, TIOCSWINSZ, (char *)&shttyinfo.winsize);
    }
#endif /* TIOCGWINSZ */

    if (zleactive && resetzle) {
#ifdef TIOCGWINSZ
	winchanged =
#endif /* TIOCGWINSZ */
	    resetneeded = 1;
	zrefresh();
    }
}

/* Move a fd to a place >= 10 and mark the new fd in fdtable.  If the fd *
 * is already >= 10, it is not moved.  If it is invalid, -1 is returned. */

/**/
mod_export int
movefd(int fd)
{
    if(fd != -1 && fd < 10) {
#ifdef F_DUPFD
	int fe = fcntl(fd, F_DUPFD, 10);
#else
	int fe = movefd(dup(fd));
#endif
	zclose(fd);
	fd = fe;
    }
    if(fd != -1) {
	if (fd > max_zsh_fd) {
	    while (fd >= fdtable_size)
		fdtable = zrealloc(fdtable, (fdtable_size *= 2));
	    max_zsh_fd = fd;
	}
	fdtable[fd] = 1;
    }
    return fd;
}

/* Move fd x to y.  If x == -1, fd y is closed. */

/**/
mod_export void
redup(int x, int y)
{
    if(x < 0)
	zclose(y);
    else if (x != y) {
	while (y >= fdtable_size)
	    fdtable = zrealloc(fdtable, (fdtable_size *= 2));
	dup2(x, y);
	if ((fdtable[y] = fdtable[x]) && y > max_zsh_fd)
	    max_zsh_fd = y;
	zclose(x);
    }
}

/* Close the given fd, and clear it from fdtable. */

/**/
mod_export int
zclose(int fd)
{
    if (fd >= 0) {
	fdtable[fd] = 0;
	while (max_zsh_fd > 0 && !fdtable[max_zsh_fd])
	    max_zsh_fd--;
	if (fd == coprocin)
	    coprocin = -1;
	if (fd == coprocout)
	    coprocout = -1;
    }
    return close(fd);
}

/* Get a file name relative to $TMPPREFIX which *
 * is unique, for use as a temporary file.      */
 
/**/
mod_export char *
gettempname(void)
{
    char *s;
 
    if (!(s = getsparam("TMPPREFIX")))
	s = DEFAULT_TMPPREFIX;
 
    return ((char *) mktemp(dyncat(unmeta(s), "XXXXXX")));
}

/* Check if a string contains a token */

/**/
mod_export int
has_token(const char *s)
{
    while(*s)
	if(itok(*s++))
	    return 1;
    return 0;
}

/* Delete a character in a string */
 
/**/
mod_export void
chuck(char *str)
{
    while ((str[0] = str[1]))
	str++;
}

/**/
mod_export int
tulower(int c)
{
    c &= 0xff;
    return (isupper(c) ? tolower(c) : c);
}

/**/
mod_export int
tuupper(int c)
{
    c &= 0xff;
    return (islower(c) ? toupper(c) : c);
}

/* copy len chars from t into s, and null terminate */

/**/
void
ztrncpy(char *s, char *t, int len)
{
    while (len--)
	*s++ = *t++;
    *s = '\0';
}

/* copy t into *s and update s */

/**/
mod_export void
strucpy(char **s, char *t)
{
    char *u = *s;

    while ((*u++ = *t++));
    *s = u - 1;
}

/**/
mod_export void
struncpy(char **s, char *t, int n)
{
    char *u = *s;

    while (n--)
	*u++ = *t++;
    *s = u;
    *u = '\0';
}

/* Return the number of elements in an array of pointers. *
 * It doesn't count the NULL pointer at the end.          */

/**/
mod_export int
arrlen(char **s)
{
    int count;

    for (count = 0; *s; s++, count++);
    return count;
}

/* Skip over a balanced pair of parenthesis. */

/**/
mod_export int
skipparens(char inpar, char outpar, char **s)
{
    int level;

    if (**s != inpar)
	return -1;

    for (level = 1; *++*s && level;)
	if (**s == inpar)
	   ++level;
	else if (**s == outpar)
	   --level;

   return level;
}

/* Convert string to zlong (see zsh.h).  This function (without the z) *
 * is contained in the ANSI standard C library, but a lot of them seem *
 * to be broken.                                                       */

/**/
mod_export zlong
zstrtol(const char *s, char **t, int base)
{
    zlong ret = 0;
    int neg;

    while (inblank(*s))
	s++;

    if ((neg = (*s == '-')))
	s++;
    else if (*s == '+')
	s++;

    if (!base) {
	if (*s != '0')
	    base = 10;
	else if (*++s == 'x' || *s == 'X')
	    base = 16, s++;
	else
	    base = 8;
    }
    if (base <= 10)
	for (; *s >= '0' && *s < ('0' + base); s++)
	    ret = ret * base + *s - '0';
    else
	for (; idigit(*s) || (*s >= 'a' && *s < ('a' + base - 10))
	     || (*s >= 'A' && *s < ('A' + base - 10)); s++)
	    ret = ret * base + (idigit(*s) ? (*s - '0') : (*s & 0x1f) + 9);
    if (t)
	*t = (char *)s;
    return neg ? -ret : ret;
}

/**/
int
setblock_stdin(void)
{
#ifdef O_NDELAY
# ifdef O_NONBLOCK
#  define NONBLOCK (O_NDELAY|O_NONBLOCK)
# else /* !O_NONBLOCK */
#  define NONBLOCK O_NDELAY
# endif /* !O_NONBLOCK */
#else /* !O_NDELAY */
# ifdef O_NONBLOCK
#  define NONBLOCK O_NONBLOCK
# else /* !O_NONBLOCK */
#  define NONBLOCK 0
# endif /* !O_NONBLOCK */
#endif /* !O_NDELAY */

#if NONBLOCK
    struct stat st;
    long mode;

    if (!fstat(0, &st) && !S_ISREG(st.st_mode)) {
	mode = fcntl(0, F_GETFL, 0);
	if (mode != -1 && (mode & NONBLOCK) &&
	    !fcntl(0, F_SETFL, mode & ~NONBLOCK))
	    return 1;
    }
#endif /* NONBLOCK */
    return 0;

#undef NONBLOCK
}

/**/
int
checkrmall(char *s)
{
    fprintf(shout, "zsh: sure you want to delete all the files in ");
    if (*s != '/') {
	nicezputs(pwd[1] ? unmeta(pwd) : "", shout);
	fputc('/', shout);
    }
    nicezputs(s, shout);
    if(isset(RMSTARWAIT)) {
	fputs("? (waiting ten seconds)", shout);
	fflush(shout);
	zbeep();
	sleep(10);
	fputc('\n', shout);
    }
    fputs(" [yn]? ", shout);
    fflush(shout);
    zbeep();
    return (getquery("ny", 1) == 'y');
}

/**/
int
read1char(void)
{
    char c;

    while (read(SHTTY, &c, 1) != 1) {
	if (errno != EINTR || errflag)
	    return -1;
    }
    return STOUC(c);
}

/**/
int
getquery(char *valid_chars, int purge)
{
    int c, d;
    int isem = !strcmp(term, "emacs");

#ifdef FIONREAD
    int val = 0;
#endif

    attachtty(mypgrp);
    if (!isem)
	setcbreak();

#ifdef FIONREAD
    ioctl(SHTTY, FIONREAD, (char *)&val);
    if(purge) {
	while(val--)
	    read(SHTTY, &c, 1);
    } else if (val) {
	if (!isem)
	    settyinfo(&shttyinfo);
	write(SHTTY, "n\n", 2);
	return 'n';
    }
#endif
    while ((c = read1char()) >= 0) {
	if (c == 'Y' || c == '\t')
	    c = 'y';
	else if (c == 'N')
	    c = 'n';
	if (!valid_chars)
	    break;
	if (c == '\n') {
	    c = *valid_chars;
	    break;
	}
	if (strchr(valid_chars, c)) {
	    write(SHTTY, "\n", 1);
	    break;
	}
	zbeep();
	if (icntrl(c))
	    write(SHTTY, "\b \b", 3);
	write(SHTTY, "\b \b", 3);
    }
    if (isem) {
	if (c != '\n')
	    while ((d = read1char()) >= 0 && d != '\n');
    } else {
	settyinfo(&shttyinfo);
	if (c != '\n' && !valid_chars)
	    write(SHTTY, "\n", 1);
    }
    return c;
}

static int d;
static char *guess, *best;

/**/
static void
spscan(HashNode hn, int scanflags)
{
    int nd;

    nd = spdist(hn->nam, guess, (int) strlen(guess) / 4 + 1);
    if (nd <= d) {
	best = hn->nam;
	d = nd;
    }
}

/* spellcheck a word */
/* fix s ; if hist is nonzero, fix the history list too */

/**/
mod_export void
spckword(char **s, int hist, int cmd, int ask)
{
    char *t, *u;
    int x;
    char ic = '\0';
    int ne;
    int preflen = 0;

    if ((histdone & HISTFLAG_NOEXEC) || **s == '-' || **s == '%')
	return;
    if (!strcmp(*s, "in"))
	return;
    if (!(*s)[0] || !(*s)[1])
	return;
    if (shfunctab->getnode(shfunctab, *s) ||
	builtintab->getnode(builtintab, *s) ||
	cmdnamtab->getnode(cmdnamtab, *s) ||
	aliastab->getnode(aliastab, *s)  ||
	reswdtab->getnode(reswdtab, *s))
	return;
    else if (isset(HASHLISTALL)) {
	cmdnamtab->filltable(cmdnamtab);
	if (cmdnamtab->getnode(cmdnamtab, *s))
	    return;
    }
    t = *s;
    if (*t == Tilde || *t == Equals || *t == String)
	t++;
    for (; *t; t++)
	if (itok(*t))
	    return;
    best = NULL;
    for (t = *s; *t; t++)
	if (*t == '/')
	    break;
    if (**s == Tilde && !*t)
	return;
    if (**s == String && !*t) {
	guess = *s + 1;
	if (*t || !ialpha(*guess))
	    return;
	ic = String;
	d = 100;
	scanhashtable(paramtab, 1, 0, 0, spscan, 0);
    } else if (**s == Equals) {
	if (*t)
	    return;
	if (hashcmd(guess = *s + 1, pathchecked))
	    return;
	d = 100;
	ic = Equals;
	scanhashtable(aliastab, 1, 0, 0, spscan, 0);
	scanhashtable(cmdnamtab, 1, 0, 0, spscan, 0);
    } else {
	guess = *s;
	if (*guess == Tilde || *guess == String) {
	    ic = *guess;
	    if (!*++t)
		return;
	    guess = dupstring(guess);
	    ne = noerrs;
	    noerrs = 2;
	    singsub(&guess);
	    noerrs = ne;
	    if (!guess)
		return;
	    preflen = strlen(guess) - strlen(t);
	}
	if (access(unmeta(guess), F_OK) == 0)
	    return;
	if ((u = spname(guess)) != guess)
	    best = u;
	if (!*t && cmd) {
	    if (hashcmd(guess, pathchecked))
		return;
	    d = 100;
	    scanhashtable(reswdtab, 1, 0, 0, spscan, 0);
	    scanhashtable(aliastab, 1, 0, 0, spscan, 0);
	    scanhashtable(shfunctab, 1, 0, 0, spscan, 0);
	    scanhashtable(builtintab, 1, 0, 0, spscan, 0);
	    scanhashtable(cmdnamtab, 1, 0, 0, spscan, 0);
	}
    }
    if (errflag)
	return;
    if (best && (int)strlen(best) > 1 && strcmp(best, guess)) {
	if (ic) {
	    if (preflen) {
		/* do not correct the result of an expansion */
		if (strncmp(guess, best, preflen))
		    return;
		/* replace the temporarily expanded prefix with the original */
		u = (char *) ncalloc(t - *s + strlen(best + preflen) + 1);
		strncpy(u, *s, t - *s);
		strcpy(u + (t - *s), best + preflen);
	    } else {
		u = (char *) ncalloc(strlen(best) + 2);
		strcpy(u + 1, best);
	    }
	    best = u;
	    guess = *s;
	    *guess = *best = ztokens[ic - Pound];
	}
	if (ask) {
	    char *pptbuf;
	    pptbuf = promptexpand(sprompt, 0, best, guess);
	    zputs(pptbuf, shout);
	    free(pptbuf);
	    fflush(shout);
	    zbeep();
	    x = getquery("nyae ", 0);
	} else
	    x = 'y';
	if (x == 'y' || x == ' ') {
	    *s = dupstring(best);
	    if (hist)
		hwrep(best);
	} else if (x == 'a') {
	    histdone |= HISTFLAG_NOEXEC;
	} else if (x == 'e') {
	    histdone |= HISTFLAG_NOEXEC | HISTFLAG_RECALL;
	}
	if (ic)
	    **s = ic;
    }
}

/**/
mod_export int
ztrftime(char *buf, int bufsize, char *fmt, struct tm *tm)
{
    int hr12;
#ifndef HAVE_STRFTIME
    static char *astr[] =
    {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
    static char *estr[] =
    {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
     "Aug", "Sep", "Oct", "Nov", "Dec"};
#else
    char *origbuf = buf;
#endif
    char tmp[3];


    tmp[0] = '%';
    tmp[2] = '\0';
    while (*fmt)
	if (*fmt == '%') {
	    fmt++;
	    switch (*fmt++) {
	    case 'd':
		*buf++ = '0' + tm->tm_mday / 10;
		*buf++ = '0' + tm->tm_mday % 10;
		break;
	    case 'e':
	    case 'f':
		if (tm->tm_mday > 9)
		    *buf++ = '0' + tm->tm_mday / 10;
		else if (fmt[-1] == 'e')
		    *buf++ = ' ';
		*buf++ = '0' + tm->tm_mday % 10;
		break;
	    case 'k':
	    case 'K':
		if (tm->tm_hour > 9)
		    *buf++ = '0' + tm->tm_hour / 10;
		else if (fmt[-1] == 'k')
		    *buf++ = ' ';
		*buf++ = '0' + tm->tm_hour % 10;
		break;
	    case 'l':
	    case 'L':
		hr12 = tm->tm_hour % 12;
		if (hr12 == 0)
		    hr12 = 12;
	        if (hr12 > 9)
		  *buf++ = '1';
		else if (fmt[-1] == 'l')
		  *buf++ = ' ';
		*buf++ = '0' + (hr12 % 10);
		break;
	    case 'm':
		*buf++ = '0' + (tm->tm_mon + 1) / 10;
		*buf++ = '0' + (tm->tm_mon + 1) % 10;
		break;
	    case 'M':
		*buf++ = '0' + tm->tm_min / 10;
		*buf++ = '0' + tm->tm_min % 10;
		break;
	    case 'S':
		*buf++ = '0' + tm->tm_sec / 10;
		*buf++ = '0' + tm->tm_sec % 10;
		break;
	    case 'y':
		*buf++ = '0' + (tm->tm_year / 10) % 10;
		*buf++ = '0' + tm->tm_year % 10;
		break;
#ifndef HAVE_STRFTIME
	    case 'a':
		strucpy(&buf, astr[tm->tm_wday]);
		break;
	    case 'b':
		strucpy(&buf, estr[tm->tm_mon]);
		break;
	    case 'p':
		*buf++ = (tm->tm_hour > 11) ? 'p' : 'a';
		*buf++ = 'm';
		break;
	    default:
		*buf++ = '%';
		if (fmt[-1] != '%')
		    *buf++ = fmt[-1];
#else
	    default:
		*buf = '\0';
		tmp[1] = fmt[-1];
		strftime(buf, bufsize - strlen(origbuf), tmp, tm);
		buf += strlen(buf);
#endif
		break;
	    }
	} else
	    *buf++ = *fmt++;
    *buf = '\0';
    return 0;
}

/**/
mod_export char *
zjoin(char **arr, int delim)
{
    int len = 0;
    char **s, *ret, *ptr;

    for (s = arr; *s; s++)
	len += strlen(*s) + 1;
    if (!len)
	return "";
    ptr = ret = (char *) ncalloc(len);
    for (s = arr; *s; s++) {
	strucpy(&ptr, *s);
	if (delim)
	    *ptr++ = delim;
    }
    ptr[-1] = '\0';
    return ret;
}

/* Split a string containing a colon separated list *
 * of items into an array of strings.               */

/**/
char **
colonsplit(char *s, int uniq)
{
    int ct;
    char *t, **ret, **ptr, **p;

    for (t = s, ct = 0; *t; t++) /* count number of colons */
	if (*t == ':')
	    ct++;
    ptr = ret = (char **) zalloc(sizeof(char **) * (ct + 2));

    t = s;
    do {
	s = t;
        /* move t to point at next colon */
	for (; *t && *t != ':'; t++);
	if (uniq)
	    for (p = ret; p < ptr; p++)
		if (strlen(*p) == t - s && ! strncmp(*p, s, t - s))
		    goto cont;
	*ptr = (char *) zalloc((t - s) + 1);
	ztrncpy(*ptr++, s, t - s);
      cont: ;
    }
    while (*t++);
    *ptr = NULL;
    return ret;
}

/**/
static int
skipwsep(char **s)
{
    char *t = *s;
    int i = 0;

    while (*t && iwsep(*t == Meta ? t[1] ^ 32 : *t)) {
	if (*t == Meta)
	    t++;
	t++;
	i++;
    }
    *s = t;
    return i;
}

/**/
mod_export char **
spacesplit(char *s, int allownull)
{
    char *t, **ret, **ptr;

    ptr = ret = (char **) ncalloc(sizeof(*ret) * (wordcount(s, NULL, -!allownull) + 1));

    t = s;
    skipwsep(&s);
    if (*s && isep(*s == Meta ? s[1] ^ 32 : *s))
	*ptr++ = dupstring(allownull ? "" : nulstring);
    else if (!allownull && t != s)
	*ptr++ = dupstring("");
    while (*s) {
	if (isep(*s == Meta ? s[1] ^ 32 : *s)) {
	    if (*s == Meta)
		s++;
	    s++;
	    skipwsep(&s);
	}
	t = s;
	findsep(&s, NULL);
	if (s > t || allownull) {
	    *ptr = (char *) ncalloc((s - t) + 1);
	    ztrncpy(*ptr++, t, s - t);
	} else
	    *ptr++ = dupstring(nulstring);
	t = s;
	skipwsep(&s);
    }
    if (!allownull && t != s)
	*ptr++ = dupstring("");
    *ptr = NULL;
    return ret;
}

/**/
static int
findsep(char **s, char *sep)
{
    int i;
    char *t, *tt;

    if (!sep) {
	for (t = *s; *t; t++) {
	    if (*t == Meta) {
		if (isep(t[1] ^ 32))
		    break;
		t++;
	    } else if (isep(*t))
		break;
	}
	i = t - *s;
	*s = t;
	return i;
    }
    if (!sep[0]) {
	return **s ? ++*s, 1 : -1;
    }
    for (i = 0; **s; i++) {
	for (t = sep, tt = *s; *t && *tt && *t == *tt; t++, tt++);
	if (!*t)
	    return i;
	if (*(*s)++ == Meta) {
#ifdef DEBUG
	    if (! *(*s)++)
		fprintf(stderr, "BUG: unexpected end of string in findsep()\n");
#else
	    (*s)++;
#endif
	}
    }
    return -1;
}

/**/
char *
findword(char **s, char *sep)
{
    char *r, *t;
    int sl;

    if (!**s)
	return NULL;

    if (sep) {
	sl = strlen(sep);
	r = *s;
	while (! findsep(s, sep)) {
	    r = *s += sl;
	}
	return r;
    }
    for (t = *s; *t; t++) {
	if (*t == Meta) {
	    if (! isep(t[1] ^ 32))
		break;
	    t++;
	} else if (! isep(*t))
	    break;
    }
    *s = t;
    findsep(s, sep);
    return t;
}

/**/
int
wordcount(char *s, char *sep, int mul)
{
    int r, sl, c;

    if (sep) {
	r = 1;
	sl = strlen(sep);
	for (; (c = findsep(&s, sep)) >= 0; s += sl)
	    if ((c && *(s + sl)) || mul)
		r++;
    } else {
	char *t = s;

	r = 0;
	if (mul <= 0)
	    skipwsep(&s);
	if ((*s && isep(*s == Meta ? s[1] ^ 32 : *s)) ||
	    (mul < 0 && t != s))
	    r++;
	for (; *s; r++) {
	    if (isep(*s == Meta ? s[1] ^ 32 : *s)) {
		if (*s == Meta)
		    s++;
		s++;
		if (mul <= 0)
		    skipwsep(&s);
	    }
	    findsep(&s, NULL);
	    t = s;
	    if (mul <= 0)
		skipwsep(&s);
	}
	if (mul < 0 && t != s)
	    r++;
    }
    return r;
}

/**/
mod_export char *
sepjoin(char **s, char *sep)
{
    char *r, *p, **t;
    int l, sl;
    char sepbuf[3];

    if (!*s)
	return "";
    if (!sep) {
	sep = sepbuf;
	sepbuf[0] = *ifs;
	sepbuf[1] = *ifs == Meta ? ifs[1] ^ 32 : '\0';
	sepbuf[2] = '\0';
    }
    sl = strlen(sep);
    for (t = s, l = 1 - sl; *t; l += strlen(*t) + sl, t++);
    r = p = (char *) ncalloc(l);
    t = s;
    while (*t) {
	strucpy(&p, *t);
	if (*++t)
	    strucpy(&p, sep);
    }
    *p = '\0';
    return r;
}

/**/
char **
sepsplit(char *s, char *sep, int allownull)
{
    int n, sl;
    char *t, *tt, **r, **p;

    if (!sep)
	return spacesplit(s, allownull);

    sl = strlen(sep);
    n = wordcount(s, sep, 1);
    r = p = (char **) ncalloc((n + 1) * sizeof(char *));

    for (t = s; n--;) {
	tt = t;
	findsep(&t, sep);
	*p = (char *) ncalloc(t - tt + 1);
	strncpy(*p, tt, t - tt);
	(*p)[t - tt] = '\0';
	p++;
	t += sl;
    }
    *p = NULL;

    return r;
}

/* Get the definition of a shell function */

/**/
mod_export List
getshfunc(char *nam)
{
    Shfunc shf;

    if (!(shf = (Shfunc) shfunctab->getnode(shfunctab, nam)))
	return &dummy_list;

    return shf->funcdef;
}

/* allocate a tree element */

static int sizetab[N_COUNT] = {
    sizeof(struct list),
    sizeof(struct sublist),
    sizeof(struct pline),
    sizeof(struct cmd),
    sizeof(struct redir),
    sizeof(struct cond),
    sizeof(struct forcmd),
    sizeof(struct casecmd),
    sizeof(struct ifcmd),
    sizeof(struct whilecmd),
    sizeof(struct varasg),
    sizeof(struct autofn),
};

static int offstab[N_COUNT] = {
    offsetof(struct list, left),
    offsetof(struct sublist, left),
    offsetof(struct pline, left),
    offsetof(struct cmd, u),
    offsetof(struct redir, name),
    offsetof(struct cond, left),
    offsetof(struct forcmd, name),
    offsetof(struct casecmd, pats),
    offsetof(struct ifcmd, ifls),
    offsetof(struct whilecmd, cont),
    offsetof(struct varasg, name),
    sizeof(struct autofn),
};

static int flagtab[N_COUNT] = {
    NT_SET(N_LIST, NT_NODE, NT_NODE, 0, 0),
    NT_SET(N_SUBLIST, NT_NODE, NT_NODE, 0, 0),
    NT_SET(N_PLINE, NT_NODE, NT_NODE, 0, 0),
    NT_SET(N_CMD, NT_NODE, NT_STR | NT_LIST, NT_NODE | NT_LIST, NT_NODE | NT_LIST),
    NT_SET(N_REDIR, NT_STR, 0, 0, 0),
    NT_SET(N_COND, NT_NODE, NT_NODE, NT_PAT, 0),
    NT_SET(N_FOR, NT_STR, NT_STR, NT_STR, NT_NODE),
    NT_SET(N_CASE, NT_STR | NT_ARR, NT_PAT | NT_ARR, NT_NODE | NT_ARR, 0),
    NT_SET(N_IF, NT_NODE | NT_ARR, NT_NODE | NT_ARR, 0, 0),
    NT_SET(N_WHILE, NT_NODE, NT_NODE, 0, 0),
    NT_SET(N_VARASG, NT_STR, NT_STR, NT_STR | NT_LIST, 0),
    NT_SET(N_AUTOFN, 0, 0, 0, 0),
};

/**/
void *
allocnode(int type)
{
    struct node *n;

    n = (struct node *) ncalloc(sizetab[type]);
    memset((void *) n, 0, sizetab[type]);
    n->ntype = flagtab[type];

    return (void *) n;
}
 
/* duplicate a syntax tree */

/**/
mod_export void *
dupstruct(void *a)
{
    void **onodes, **nnodes, *ret, *n, *on;
    int type;
    size_t nodeoffs;

    if (!a || ((List) a) == &dummy_list)
	return a;
    type = *(int *)a;
    ret = alloc(sizetab[NT_TYPE(type)]);
    memcpy(ret, a, nodeoffs = offstab[NT_TYPE(type)]);
    onodes = (void **) ((char *)a + nodeoffs);
    nnodes = (void **) ((char *)ret + nodeoffs);
    for (type = (type & 0xffff00) >> 4; (type >>= 4); *nnodes++ = n) {
	if (!(on = *onodes++))
	    n = NULL;
	else {
	    switch (type & 0xf) {
	    case NT_NODE:
		n = dupstruct(on);
		break;
	    case NT_STR:
		n = dupstring(on);
		break;
	    case NT_PAT:
		n = duppatprog(on);
		break;
	    case NT_LIST | NT_NODE:
		n = duplist(on, (VFunc) dupstruct);
		break;
	    case NT_LIST | NT_STR:
		n = duplist(on, (VFunc) (useheap ? dupstring : ztrdup));
		break;
	    case NT_LIST | NT_PAT:
		n = duplist(on, (VFunc) duppatprog);
		break;
	    case NT_NODE | NT_ARR:
		n = duparray(on, (VFunc) dupstruct);
		break;
	    case NT_STR | NT_ARR:
		n = duparray(on, (VFunc) (useheap ? dupstring : ztrdup));
		break;
	    case NT_PAT | NT_ARR:
		n = duparray(on, (VFunc) duppatprog);
		break;
	    default:
		DPUTS(1, "BUG: bad node type in dupstruct()");
		abort();
	    }
	}
    }
    return ret;
}

/* Free a syntax tree. Now, freestruct() only registers everything that
 * has to be freed. Later, freestructs() will be called to do the real
 * work. This is to avoid having functions that are currently executed
 * free themselves by re-defining themselves. */

static LinkList freeslist = NULL;

/**/
mod_export void
freestruct(void *a)
{
    if (!a || ((List) a) == &dummy_list)
	return;

    PERMALLOC {
	if (!freeslist)
	    freeslist = newlinklist();
	addlinknode(freeslist, a);
    } LASTALLOC;
}

/**/
void
freestructs(void)
{
    void *a;

    if (freeslist)
	while ((a = getlinknode(freeslist)))
	    ifreestruct(a);
}

/**/
static void
ifreestruct(void *a)
{
    void **nodes, *n;
    int type, size;

    type = *(int *) a;
    nodes = (void **) ((char *)a + offstab[NT_TYPE(type)]);
    size = sizetab[NT_TYPE(type)];
    for (type = (type & 0xffff00) >> 4; (type >>= 4);) {
	if ((n = *nodes++)) {
	    switch (type & 0xf) {
	    case NT_NODE:
		freestruct(n);
		break;
	    case NT_STR:
		zsfree((char *) n);
		break;
	    case NT_PAT:
		freepatprog((Patprog) n);
		break;
	    case NT_LIST | NT_NODE:
		freelinklist((LinkList) n, (FreeFunc) freestruct);
		break;
	    case NT_LIST | NT_STR:
		freelinklist((LinkList) n, (FreeFunc) zsfree);
		break;
	    case NT_LIST | NT_PAT:
		freelinklist((LinkList) n, (FreeFunc) freepatprog);
		break;
	    case NT_NODE | NT_ARR:
		{
		    void **p = (void **) n;

		    while (*p)
			freestruct(*p++);
		    zfree(n, sizeof(void *) * (p + 1 - (void **) n));
		    break;
		}
	    case NT_STR | NT_ARR:
		freearray((char **) n);
		break;
	    case NT_PAT | NT_ARR:
		{
		    Patprog *p = (Patprog *) n;

		    while (*p)
			freepatprog(*p++);
		    zfree(n, sizeof(void *) * ((void **) p + 1 - (void **) n));
		    break;
		}
	    default:
		DPUTS(1, "BUG: bad node type in freenode()");
		abort();
	    }
	}
    }
#if 0
    DPUTS(size != ((char *) nodes) - ((char *) a),
	"BUG: size wrong in freenode()");
#endif
    zfree(a, size);
}

/**/
LinkList
dupheaplist(LinkList l)
{
    if (!l)
	return NULL;

    return duplist(l, (VFunc) dupstruct);
}

/**/
static LinkList
duplist(LinkList l, VFunc func)
{
    if (l && nonempty(l)) {
	LinkList ret;
	LinkNode node;

	ret = newlinklist();
	for (node = firstnode(l); node; incnode(node))
	    addlinknode(ret, func(getdata(node)));
	return ret;
    }
    return NULL;
}

/**/
char **
duparray(char **arr, VFunc func)
{
    if (arr && *arr) {
	char **ret, **rr, *p;

	ret = (char **) alloc((arrlen(arr) + 1) * sizeof(char *));
	for (rr = ret; (p = *arr++);)
	    *rr++ = (char *)func(p);
	*rr = NULL;

	return ret;
    }
    return NULL;
}

/**/
char **
mkarray(char *s)
{
    char **t = (char **) zalloc((s) ? (2 * sizeof s) : (sizeof s));

    if ((*t = s))
	t[1] = NULL;
    return t;
}

/**/
mod_export void
zbeep(void)
{
    char *vb;
    if ((vb = getsparam("ZBEEP"))) {
	int len;
	vb = getkeystring(vb, &len, 2, NULL);
	write(SHTTY, vb, len);
    } else if (isset(BEEP))
	write(SHTTY, "\07", 1);
}

/**/
mod_export void
freearray(char **s)
{
    char **t = s;

    DPUTS(!s, "freearray() with zero argument");

    while (*s)
	zsfree(*s++);
    free(t);
}

/**/
int
equalsplit(char *s, char **t)
{
    for (; *s && *s != '='; s++);
    if (*s == '=') {
	*s++ = '\0';
	*t = s;
	return 1;
    }
    return 0;
}

/* the ztypes table */

/**/
mod_export short int typtab[256];

/* initialize the ztypes table */

/**/
void
inittyptab(void)
{
    int t0;
    char *s;

    for (t0 = 0; t0 != 256; t0++)
	typtab[t0] = 0;
    for (t0 = 0; t0 != 32; t0++)
	typtab[t0] = typtab[t0 + 128] = ICNTRL;
    typtab[127] = ICNTRL;
    for (t0 = '0'; t0 <= '9'; t0++)
	typtab[t0] = IDIGIT | IALNUM | IWORD | IIDENT | IUSER;
    for (t0 = 'a'; t0 <= 'z'; t0++)
	typtab[t0] = typtab[t0 - 'a' + 'A'] = IALPHA | IALNUM | IIDENT | IUSER | IWORD;
    for (t0 = 0240; t0 != 0400; t0++)
	typtab[t0] = IALPHA | IALNUM | IIDENT | IUSER | IWORD;
    typtab['.'] |= IIDENT;
    typtab['_'] = IIDENT | IUSER;
    typtab['-'] = IUSER;
    typtab[' '] |= IBLANK | INBLANK;
    typtab['\t'] |= IBLANK | INBLANK;
    typtab['\n'] |= INBLANK;
    typtab['\0'] |= IMETA;
    typtab[STOUC(Meta)  ] |= IMETA;
    typtab[STOUC(Marker)] |= IMETA;
    for (t0 = (int)STOUC(Pound); t0 <= (int)STOUC(Nularg); t0++)
	typtab[t0] |= ITOK | IMETA;
    for (s = ifs ? ifs : DEFAULT_IFS; *s; s++) {
	if (inblank(*s)) {
	    if (s[1] == *s)
		s++;
	    else
		typtab[STOUC(*s)] |= IWSEP;
	}
	typtab[STOUC(*s == Meta ? *++s ^ 32 : *s)] |= ISEP;
    }
    for (s = wordchars ? wordchars : DEFAULT_WORDCHARS; *s; s++)
	typtab[STOUC(*s == Meta ? *++s ^ 32 : *s)] |= IWORD;
    for (s = SPECCHARS; *s; s++)
	typtab[STOUC(*s)] |= ISPECIAL;
    if (isset(BANGHIST) && bangchar && interact && isset(SHINSTDIN))
	typtab[bangchar] |= ISPECIAL;
}

/**/
mod_export char **
arrdup(char **s)
{
    char **x, **y;

    y = x = (char **) ncalloc(sizeof(char *) * (arrlen(s) + 1));

    while ((*x++ = dupstring(*s++)));
    return y;
}

/* Duplicate a list of strings. */

/**/
LinkList
listdup(LinkList l)
{
    if (!l)
	return NULL;
    else {
	LinkList r = newlinklist();
	LinkNode n;

	for (n = firstnode(l); n; incnode(n))
	    addlinknode(r, dupstring((char *) getdata(n)));

	return r;
    }
}

/**/
char **
listarr(LinkList l)
{
    char **x, **y;
    LinkNode n;

    x = y = (char **) ncalloc((countlinknodes(l) + 1) * sizeof(char *));

    for (n = firstnode(l); n; incnode(n))
	*x++ = dupstring((char *) getdata(n));
    *x = NULL;
    return y;
}

/**/
static char *
spname(char *oldname)
{
    char *p, spnameguess[PATH_MAX + 1], spnamebest[PATH_MAX + 1];
    static char newname[PATH_MAX + 1];
    char *new = newname, *old;
    int bestdist = 200, thisdist;

    old = oldname;
    for (;;) {
	while (*old == '/')
	    *new++ = *old++;
	*new = '\0';
	if (*old == '\0')
	    return newname;
	p = spnameguess;
	for (; *old != '/' && *old != '\0'; old++)
	    if (p < spnameguess + PATH_MAX)
		*p++ = *old;
	*p = '\0';
	if ((thisdist = mindist(newname, spnameguess, spnamebest)) >= 3) {
	    if (bestdist < 3) {
		strcpy(new, spnameguess);
		strcat(new, old);
		return newname;
	    } else
	    	return NULL;
	} else
	    bestdist = thisdist;
	for (p = spnamebest; (*new = *p++);)
	    new++;
    }
}

/**/
static int
mindist(char *dir, char *mindistguess, char *mindistbest)
{
    int mindistd, nd;
    DIR *dd;
    char *fn;
    char buf[PATH_MAX];

    if (dir[0] == '\0')
	dir = ".";
    mindistd = 100;
    sprintf(buf, "%s/%s", dir, mindistguess);
    if (access(unmeta(buf), F_OK) == 0) {
	strcpy(mindistbest, mindistguess);
	return 0;
    }
    if (!(dd = opendir(unmeta(dir))))
	return mindistd;
    while ((fn = zreaddir(dd, 0))) {
	nd = spdist(fn, mindistguess,
		    (int)strlen(mindistguess) / 4 + 1);
	if (nd <= mindistd) {
	    strcpy(mindistbest, fn);
	    mindistd = nd;
	    if (mindistd == 0)
		break;
	}
    }
    closedir(dd);
    return mindistd;
}

/**/
static int
spdist(char *s, char *t, int thresh)
{
    char *p, *q;
    char *keymap =
    "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\
\t1234567890-=\t\
\tqwertyuiop[]\t\
\tasdfghjkl;'\n\t\
\tzxcvbnm,./\t\t\t\
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\
\t!@#$%^&*()_+\t\
\tQWERTYUIOP{}\t\
\tASDFGHJKL:\"\n\t\
\tZXCVBNM<>?\n\n\t\
\n\n\n\n\n\n\n\n\n\n\n\n\n\n";

    if (!strcmp(s, t))
	return 0;
/* any number of upper/lower mistakes allowed (dist = 1) */
    for (p = s, q = t; *p && tulower(*p) == tulower(*q); p++, q++);
    if (!*p && !*q)
	return 1;
    if (!thresh)
	return 200;
    for (p = s, q = t; *p && *q; p++, q++)
	if (*p == *q)
	    continue;		/* don't consider "aa" transposed, ash */
	else if (p[1] == q[0] && q[1] == p[0])	/* transpositions */
	    return spdist(p + 2, q + 2, thresh - 1) + 1;
	else if (p[1] == q[0])	/* missing letter */
	    return spdist(p + 1, q + 0, thresh - 1) + 2;
	else if (p[0] == q[1])	/* missing letter */
	    return spdist(p + 0, q + 1, thresh - 1) + 2;
	else if (*p != *q)
	    break;
    if ((!*p && strlen(q) == 1) || (!*q && strlen(p) == 1))
	return 2;
    for (p = s, q = t; *p && *q; p++, q++)
	if (p[0] != q[0] && p[1] == q[1]) {
	    int t0;
	    char *z;

	/* mistyped letter */

	    if (!(z = strchr(keymap, p[0])) || *z == '\n' || *z == '\t')
		return spdist(p + 1, q + 1, thresh - 1) + 1;
	    t0 = z - keymap;
	    if (*q == keymap[t0 - 15] || *q == keymap[t0 - 14] ||
		*q == keymap[t0 - 13] ||
		*q == keymap[t0 - 1] || *q == keymap[t0 + 1] ||
		*q == keymap[t0 + 13] || *q == keymap[t0 + 14] ||
		*q == keymap[t0 + 15])
		return spdist(p + 1, q + 1, thresh - 1) + 2;
	    return 200;
	} else if (*p != *q)
	    break;
    return 200;
}

/* set cbreak mode, or the equivalent */

/**/
void
setcbreak(void)
{
    struct ttyinfo ti;

    ti = shttyinfo;
#ifdef HAS_TIO
    ti.tio.c_lflag &= ~ICANON;
    ti.tio.c_cc[VMIN] = 1;
    ti.tio.c_cc[VTIME] = 0;
#else
    ti.sgttyb.sg_flags |= CBREAK;
#endif
    settyinfo(&ti);
}

/* give the tty to some process */

/**/
mod_export void
attachtty(pid_t pgrp)
{
    static int ep = 0;

    if (jobbing) {
#ifdef HAVE_TCSETPGRP
	if (SHTTY != -1 && tcsetpgrp(SHTTY, pgrp) == -1 && !ep)
#else
# if ardent
	if (SHTTY != -1 && setpgrp() == -1 && !ep)
# else
	int arg = pgrp;

	if (SHTTY != -1 && ioctl(SHTTY, TIOCSPGRP, &arg) == -1 && !ep)
# endif
#endif
	{
	    if (pgrp != mypgrp && kill(-pgrp, 0) == -1)
		attachtty(mypgrp);
	    else {
		if (errno != ENOTTY)
		{
		    zerr("can't set tty pgrp: %e", NULL, errno);
		    fflush(stderr);
		}
		opts[MONITOR] = 0;
		ep = 1;
		errflag = 0;
	    }
	}
    }
}

/* get the process group associated with the tty */

/**/
pid_t
gettygrp(void)
{
    pid_t arg;

    if (SHTTY == -1)
	return -1;

#ifdef HAVE_TCSETPGRP
    arg = tcgetpgrp(SHTTY);
#else
    ioctl(SHTTY, TIOCGPGRP, &arg);
#endif

    return arg;
}

/* Return the output baudrate */

#ifdef HAVE_SELECT
/**/
long
getbaudrate(struct ttyinfo *shttyinfo)
{
    long speedcode;

#ifdef HAS_TIO
# if defined(HAVE_TCGETATTR) && defined(HAVE_TERMIOS_H)
    speedcode = cfgetospeed(&shttyinfo->tio);
# else
    speedcode = shttyinfo->tio.c_cflag & CBAUD;
# endif
#else
    speedcode = shttyinfo->sgttyb.sg_ospeed;
#endif

    switch (speedcode) {
    case B0:
	return (0L);
    case B50:
	return (50L);
    case B75:
	return (75L);
    case B110:
	return (110L);
    case B134:
	return (134L);
    case B150:
	return (150L);
    case B200:
	return (200L);
    case B300:
	return (300L);
    case B600:
	return (600L);
#ifdef _B900
    case _B900:
	return (900L);
#endif
    case B1200:
	return (1200L);
    case B1800:
	return (1800L);
    case B2400:
	return (2400L);
#ifdef _B3600
    case _B3600:
	return (3600L);
#endif
    case B4800:
	return (4800L);
#ifdef _B7200
    case _B7200:
	return (7200L);
#endif
    case B9600:
	return (9600L);
#ifdef B19200
    case B19200:
	return (19200L);
#else
# ifdef EXTA
    case EXTA:
	return (19200L);
# endif
#endif
#ifdef B38400
    case B38400:
	return (38400L);
#else
# ifdef EXTB
    case EXTB:
	return (38400L);
# endif
#endif
#ifdef B57600
    case B57600:
	return (57600L);
#endif
#ifdef B115200
    case B115200:
	return (115200L);
#endif
#ifdef B230400
    case B230400:
	return (230400L);
#endif
#ifdef B460800
    case B460800:
	return (460800L);
#endif
    default:
	if (speedcode >= 100)
	    return speedcode;
	break;
    }
    return (0L);
}
#endif

/* Escape tokens and null characters.  Buf is the string which should be     *
 * escaped.  len is the length of the string.  If len is -1, buf should be   *
 * null terminated.  If len is non-negative and the third paramerer is not   *
 * META_DUP, buf should point to an at least len+1 long memory area.  The    *
 * return value points to the quoted string.  If the given string does not   *
 * contain any special character which should be quoted and the third        *
 * parameter is not META_(HEAP|)DUP, buf is returned unchanged (a            *
 * terminating null character is appended to buf if necessary).  Otherwise   *
 * the third `heap' argument determines the method used to allocate space    *
 * for the result.  It can have the following values:                        *
 *   META_REALLOC:  use zrealloc on buf                                      *
 *   META_HREALLOC: use hrealloc on buf                                      *
 *   META_USEHEAP:  get memory from the heap.  This leaves buf unchanged.    *
 *   META_NOALLOC:  buf points to a memory area which is long enough to hold *
 *                  the quoted form, just quote it and return buf.           *
 *   META_STATIC:   store the quoted string in a static area.  The original  *
 *                  sting should be at most PATH_MAX long.                   *
 *   META_ALLOC:    allocate memory for the new string with zalloc().        *
 *   META_DUP:      leave buf unchanged and allocate space for the return    *
 *                  value even if buf does not contains special characters   *
 *   META_HEAPDUP:  same as META_DUP, but uses the heap                      */

/**/
mod_export char *
metafy(char *buf, int len, int heap)
{
    int meta = 0;
    char *t, *p, *e;
    static char mbuf[PATH_MAX*2+1];

    if (len == -1) {
	for (e = buf, len = 0; *e; len++)
	    if (imeta(*e++))
		meta++;
    } else
	for (e = buf; e < buf + len;)
	    if (imeta(*e++))
		meta++;

    if (meta || heap == META_DUP || heap == META_HEAPDUP) {
	switch (heap) {
	case META_REALLOC:
	    buf = zrealloc(buf, len + meta + 1);
	    break;
	case META_HREALLOC:
	    buf = hrealloc(buf, len, len + meta + 1);
	    break;
	case META_ALLOC:
	case META_DUP:
	    buf = memcpy(zalloc(len + meta + 1), buf, len);
	    break;
	case META_USEHEAP:
	case META_HEAPDUP:
	    buf = memcpy(zhalloc(len + meta + 1), buf, len);
	    break;
	case META_STATIC:
#ifdef DEBUG
	    if (len > PATH_MAX) {
		fprintf(stderr, "BUG: len = %d > PATH_MAX in metafy\n", len);
		fflush(stderr);
	    }
#endif
	    buf = memcpy(mbuf, buf, len);
	    break;
#ifdef DEBUG
	case META_NOALLOC:
	    break;
	default:
	    fprintf(stderr, "BUG: metafy called with invaild heap value\n");
	    fflush(stderr);
	    break;
#endif
	}
	p = buf + len;
	e = t = buf + len + meta;
	while (meta) {
	    if (imeta(*--t = *--p)) {
		*t-- ^= 32;
		*t = Meta;
		meta--;
	    }
	}
    }
    *e = '\0';
    return buf;
}

/**/
mod_export char *
unmetafy(char *s, int *len)
{
    char *p, *t;

    for (p = s; *p && *p != Meta; p++);
    for (t = p; (*t = *p++);)
	if (*t++ == Meta)
	    t[-1] = *p++ ^ 32;
    if (len)
	*len = t - s;
    return s;
}

/* Return the character length of a metafied substring, given the      *
 * unmetafied substring length.                                        */

/**/
mod_export int
metalen(const char *s, int len)
{
    int mlen = len;

    while (len--) {
	if (*s++ == Meta) {
	    mlen++;
	    s++;
	}
    }
    return mlen;
}

/* This function converts a zsh internal string to a form which can be *
 * passed to a system call as a filename.  The result is stored in a   *
 * single static area.  NULL returned if the result is longer than     *
 * 4 * PATH_MAX.                                                       */

/**/
mod_export char *
unmeta(const char *file_name)
{
    static char fn[4 * PATH_MAX];
    char *p;
    const char *t;

    for (t = file_name, p = fn; *t && p < fn + 4 * PATH_MAX - 1; p++)
	if ((*p = *t++) == Meta)
	    *p = *t++ ^ 32;
    if (*t)
	return NULL;
    if (p - fn == t - file_name)
	return (char *) file_name;
    *p = '\0';
    return fn;
}

/* Unmetafy and compare two strings, with unsigned characters. *
 * "a\0" sorts after "a".                                      */

/**/
int
ztrcmp(unsigned char const *s1, unsigned char const *s2)
{
    int c1, c2;

    while(*s1 && *s1 == *s2) {
	s1++;
	s2++;
    }

    if(!(c1 = *s1))
	c1 = -1;
    else if(c1 == STOUC(Meta))
	c1 = *++s1 ^ 32;
    if(!(c2 = *s2))
	c2 = -1;
    else if(c2 == STOUC(Meta))
	c2 = *++s2 ^ 32;

    if(c1 == c2)
	return 0;
    else if(c1 < c2)
	return -1;
    else
	return 1;
}

/* Return zero if the metafied string s and the non-metafied,  *
 * len-long string r are the same.  Return -1 if r is a prefix *
 * of s.  Return 1 if r is the lowercase version of s.  Return *
 * 2 is r is the lowercase prefix of s and return 3 otherwise. */

/**/
mod_export int
metadiffer(char const *s, char const *r, int len)
{
    int l = len;

    while (l-- && *s && *r++ == (*s == Meta ? *++s ^ 32 : *s))
	s++;
    if (*s && l < 0)
	return -1;
    if (l < 0)
	return 0;
    if (!*s)
	return 3;
    s -= len - l - 1;
    r -= len - l;
    while (len-- && *s && *r++ == tulower(*s == Meta ? *++s ^ 32 : *s))
	s++;
    if (*s && len < 0)
	return 2;
    if (len < 0)
	return 1;
    return 3;
}

/* Return the unmetafied length of a metafied string. */

/**/
mod_export int
ztrlen(char const *s)
{
    int l;

    for (l = 0; *s; l++)
	if (*s++ == Meta) {
#ifdef DEBUG
	    if (! *s)
		fprintf(stderr, "BUG: unexpected end of string in ztrlen()\n");
	    else
#endif
	    s++;
	}
    return l;
}

/* Subtract two pointers in a metafied string. */

/**/
mod_export int
ztrsub(char const *t, char const *s)
{
    int l = t - s;

    while (s != t)
	if (*s++ == Meta) {
#ifdef DEBUG
	    if (! *s || s == t)
		fprintf(stderr, "BUG: substring ends in the middle of a metachar in ztrsub()\n");
	    else
#endif
	    s++;
	    l--;
	}
    return l;
}

/**/
mod_export char *
zreaddir(DIR *dir, int ignoredots)
{
    struct dirent *de;

    do {
	de = readdir(dir);
	if(!de)
	    return NULL;
    } while(ignoredots && de->d_name[0] == '.' &&
	(!de->d_name[1] || (de->d_name[1] == '.' && !de->d_name[2])));

    return metafy(de->d_name, -1, META_STATIC);
}

/* Unmetafy and output a string.  Tokens are skipped. */

/**/
mod_export int
zputs(char const *s, FILE *stream)
{
    int c;

    while (*s) {
	if (*s == Meta)
	    c = *++s ^ 32;
	else if(itok(*s)) {
	    s++;
	    continue;
	} else
	    c = *s;
	s++;
	if (fputc(c, stream) < 0)
	    return EOF;
    }
    return 0;
}

/* Create a visibly-represented duplicate of a string. */

/**/
static char *
nicedup(char const *s, int heap)
{
    int c, len = strlen(s) * 5;
    VARARR(char, buf, len);
    char *p = buf, *n;

    while ((c = *s++)) {
	if (itok(c)) {
	    if (c <= Comma)
		c = ztokens[c - Pound];
	    else 
		continue;
	}
	if (c == Meta)
	    c = *s++ ^ 32;
	n = nicechar(c);
	while(*n)
	    *p++ = *n++;
    }
    return metafy(buf, p - buf, (heap ? META_HEAPDUP : META_DUP));
}

/**/
mod_export char *
niceztrdup(char const *s)
{
    return nicedup(s, 0);
}

/**/
char *
nicedupstring(char const *s)
{
    return nicedup(s, 1);
}

/* Unmetafy and output a string, displaying special characters readably. */

/**/
mod_export int
nicezputs(char const *s, FILE *stream)
{
    int c;

    while ((c = *s++)) {
	if (itok(c)) {
	    if (c <= Comma)
		c = ztokens[c - Pound];
	    else 
		continue;
	}
	if (c == Meta)
	    c = *s++ ^ 32;
	if(fputs(nicechar(c), stream) < 0)
	    return EOF;
    }
    return 0;
}

/* Return the length of the visible representation of a metafied string. */

/**/
mod_export size_t
niceztrlen(char const *s)
{
    size_t l = 0;
    int c;

    while ((c = *s++)) {
	if (itok(c)) {
	    if (c <= Comma)
		c = ztokens[c - Pound];
	    else 
		continue;
	}
	if (c == Meta)
	    c = *s++ ^ 32;
	l += strlen(nicechar(STOUC(c)));
    }
    return l;
}

/* check for special characters in the string */

/**/
mod_export int
hasspecial(char const *s)
{
    for (; *s; s++)
	if (ispecial(*s == Meta ? *++s ^ 32 : *s))
	    return 1;
    return 0;
}

/* Quote the string s and return the result.  If e is non-zero, the         *
 * pointer it points to may point to a position in s and in e the position  *
 * of the corresponding character in the quoted string is returned.         *
 * The last argument should be zero if this is to be used outside a string, *
 * one if it is to be quoted for the inside of a single quoted string, and  *
 * two if it is for the inside of  double quoted string.                    *
 * The string may be metafied and contain tokens.                           */

/**/
mod_export char *
bslashquote(const char *s, char **e, int instring)
{
    const char *u, *tt;
    char *v;
    char *buf = ncalloc(4 * strlen(s) + 1);
    int sf = 0;

    tt = v = buf;
    u = s;
    for (; *u; u++) {
	if (e && *e == u)
	    *e = v, sf = 1;
	if (instring == 3) {
	  int c = *u;
	  if (c == Meta) {
	    c = *++u ^ 32;
	  }
	  c &= 0xff;
	  if(isprint(c)) {
	    switch (c) {
	    case '\\':
	    case '\'':
	      *v++ = '\\';
	      *v++ = c;
	      break;

	    default:
	      if(imeta(c)) {
		*v++ = Meta;
		*v++ = c ^ 32;
	      }
	      else {
		if (isset(BANGHIST) && c == bangchar) {
		  *v++ = '\\';
		}
		*v++ = c;
	      }
	      break;
	    }
	  }
	  else {
	    switch (c) {
	    case '\0':
	      *v++ = '\\';
	      *v++ = '0';
	      if ('0' <= u[1] && u[1] <= '7') {
		*v++ = '0';
		*v++ = '0';
	      }
	      break;

	    case '\007': *v++ = '\\'; *v++ = 'a'; break;
	    case '\b': *v++ = '\\'; *v++ = 'b'; break;
	    case '\f': *v++ = '\\'; *v++ = 'f'; break;
	    case '\n': *v++ = '\\'; *v++ = 'n'; break;
	    case '\r': *v++ = '\\'; *v++ = 'r'; break;
	    case '\t': *v++ = '\\'; *v++ = 't'; break;
	    case '\v': *v++ = '\\'; *v++ = 'v'; break;

	    default:
	      *v++ = '\\';
	      *v++ = '0' + ((c >> 6) & 7);
	      *v++ = '0' + ((c >> 3) & 7);
	      *v++ = '0' + (c & 7);
	      break;
	    }
	  }
	  continue;
	}
	else if (ispecial(*u) &&
		 ((*u != '=' && *u != '~') ||
		  u == s ||
		  (isset(MAGICEQUALSUBST) && (u[-1] == '=' || u[-1] == ':')) ||
		  (*u == '~' && isset(EXTENDEDGLOB))) &&
	    (!instring ||
	     (isset(BANGHIST) && *u == (char)bangchar) ||
	     (instring == 2 &&
	      (*u == '$' || *u == '`' || *u == '\"' || *u == '\\')) ||
	     (instring == 1 && *u == '\''))) {
	    if (*u == '\n' || (instring == 1 && *u == '\'')) {
		if (unset(RCQUOTES)) {
		    *v++ = '\'';
		    if (*u == '\'')
			*v++ = '\\';
		    *v++ = *u;
		    *v++ = '\'';
		} else if (*u == '\n')
		    *v++ = '"', *v++ = '\n', *v++ = '"';
		else
		    *v++ = '\'', *v++ = '\'';
		continue;
	    } else
		*v++ = '\\';
	}
	if(*u == Meta)
	    *v++ = *u++;
	*v++ = *u;
    }
    *v = '\0';

    if (e && *e == u)
	*e = v, sf = 1;
    DPUTS(e && !sf, "BUG: Wild pointer *e in bslashquote()");

    return buf;
}

/* Unmetafy and output a string, quoted if it contains special characters. */

/**/
mod_export int
quotedzputs(char const *s, FILE *stream)
{
    int inquote = 0, c;

    /* check for empty string */
    if(!*s)
	return fputs("''", stream);

    if (!hasspecial(s))
	return zputs(s, stream);

    if (isset(RCQUOTES)) {
	/* use rc-style quotes-within-quotes for the whole string */
	if(fputc('\'', stream) < 0)
	    return EOF;
	while(*s) {
	    if (*s == Meta)
		c = *++s ^ 32;
	    else
		c = *s;
	    s++;
	    if (c == '\'') {
		if(fputc('\'', stream) < 0)
		    return EOF;
	    } else if(c == '\n' && isset(CSHJUNKIEQUOTES)) {
		if(fputc('\\', stream) < 0)
		    return EOF;
	    }
	    if(fputc(c, stream) < 0)
		return EOF;
	}
	if(fputc('\'', stream) < 0)
	    return EOF;
    } else {
	/* use Bourne-style quoting, avoiding empty quoted strings */
	while(*s) {
	    if (*s == Meta)
		c = *++s ^ 32;
	    else
		c = *s;
	    s++;
	    if (c == '\'') {
		if(inquote) {
		    if(fputc('\'', stream) < 0)
			return EOF;
		    inquote=0;
		}
		if(fputs("\\'", stream) < 0)
		    return EOF;
	    } else {
		if (!inquote) {
		    if(fputc('\'', stream) < 0)
			return EOF;
		    inquote=1;
		}
		if(c == '\n' && isset(CSHJUNKIEQUOTES)) {
		    if(fputc('\\', stream) < 0)
			return EOF;
		}
		if(fputc(c, stream) < 0)
		    return EOF;
	    }
	}
	if (inquote) {
	    if(fputc('\'', stream) < 0)
		return EOF;
	}
    }
    return 0;
}

/* Double-quote a metafied string. */

/**/
mod_export char *
dquotedztrdup(char const *s)
{
    int len = strlen(s) * 4 + 2;
    char *buf = zalloc(len);
    char *p = buf, *ret;

    if(isset(CSHJUNKIEQUOTES)) {
	int inquote = 0;

	while(*s) {
	    int c = *s++;

	    if (c == Meta)
		c = *s++ ^ 32;
	    switch(c) {
		case '"':
		case '$':
		case '`':
		    if(inquote) {
			*p++ = '"';
			inquote = 0;
		    }
		    *p++ = '\\';
		    *p++ = c;
		    break;
		default:
		    if(!inquote) {
			*p++ = '"';
			inquote = 1;
		    }
		    if(c == '\n')
			*p++ = '\\';
		    *p++ = c;
		    break;
	    }
	}
	if (inquote)
	    *p++ = '"';
    } else {
	int pending = 0;

	*p++ = '"';
	while(*s) {
	    int c = *s++;

	    if (c == Meta)
		c = *s++ ^ 32;
	    switch(c) {
		case '\\':
		    if(pending)
			*p++ = '\\';
		    *p++ = '\\';
		    pending = 1;
		    break;
		case '"':
		case '$':
		case '`':
		    if(pending)
			*p++ = '\\';
		    *p++ = '\\';
		    /* fall through */
		default:
		    *p++ = c;
		    pending = 0;
		    break;
	    }
	}
	if(pending)
	    *p++ = '\\';
	*p++ = '"';
    }
    ret = metafy(buf, p - buf, META_DUP);
    zfree(buf, len);
    return ret;
}

/* Unmetafy and output a string, double quoting it in its entirety. */

#if 0 /**/
int
dquotedzputs(char const *s, FILE *stream)
{
    char *d = dquotedztrdup(s);
    int ret = zputs(d, stream);

    zsfree(d);
    return ret;
}
#endif

/*
 * Decode a key string, turning it into the literal characters.
 * The length is returned in len.
 * fromwhere determines how the processing works.
 *   0:  Don't handle keystring, just print-like escapes.
 *       Expects misc to be present.
 *   1:  Handle Emacs-like \C-X arguments etc., but not ^X
 *       Expects misc to be present.
 *   2:  Handle ^X as well as emacs-like keys; don't handle \c
 *       for no newlines.
 *   3:  As 1, but don't handle \c.
 *   4:  Do $'...' quoting.  Overwrites the existing string instead of
 *       zhalloc'ing 
 *   5:  As 2, but \- is special.  Expects misc to be defined.
 *   6:  As 2, but parses only one character and returns end-pointer
 *       and parsed character in *misc
 */

/**/
mod_export char *
getkeystring(char *s, int *len, int fromwhere, int *misc)
{
    char *buf, tmp[1];
    char *t, *u = NULL;
    char svchar = '\0';
    int meta = 0, control = 0;

    if (fromwhere == 6)
	t = buf = tmp;
    else if (fromwhere != 4)
	t = buf = zhalloc(strlen(s) + 1);
    else {
	t = buf = s;
	s += 2;
    }
    for (; *s; s++) {
	if (*s == '\\' && s[1]) {
	    switch (*++s) {
	    case 'a':
#ifdef __STDC__
		*t++ = '\a';
#else
		*t++ = '\07';
#endif
		break;
	    case 'n':
		*t++ = '\n';
		break;
	    case 'b':
		*t++ = '\b';
		break;
	    case 't':
		*t++ = '\t';
		break;
	    case 'v':
		*t++ = '\v';
		break;
	    case 'f':
		*t++ = '\f';
		break;
	    case 'r':
		*t++ = '\r';
		break;
	    case 'E':
		if (!fromwhere) {
		    *t++ = '\\', s--;
		    continue;
		}
	    case 'e':
		*t++ = '\033';
		break;
	    case 'M':
		if (fromwhere) {
		    if (s[1] == '-')
			s++;
		    meta = 1 + control;	/* preserve the order of ^ and meta */
		} else
		    *t++ = '\\', s--;
		continue;
	    case 'C':
		if (fromwhere) {
		    if (s[1] == '-')
			s++;
		    control = 1;
		} else
		    *t++ = '\\', s--;
		continue;
	    case Meta:
		*t++ = '\\', s--;
		break;
	    case '-':
		if (fromwhere == 5) {
		    *misc  = 1;
		    break;
		}
		goto def;
	    case 'c':
		if (fromwhere < 2) {
		    *misc = 1;
		    break;
		}
	    default:
	    def:
		if ((idigit(*s) && *s < '8') || *s == 'x') {
		    if (!fromwhere) {
			if (*s == '0')
			    s++;
			else if (*s != 'x') {
			    *t++ = '\\', s--;
			    continue;
			}
		    }
		    if (s[1] && s[2] && s[3]) {
			svchar = s[3];
			s[3] = '\0';
			u = s;
		    }
		    *t++ = zstrtol(s + (*s == 'x'), &s,
				   (*s == 'x') ? 16 : 8);
		    if (svchar) {
			u[3] = svchar;
			svchar = '\0';
		    }
		    s--;
		} else {
		    if (!fromwhere && *s != '\\')
			*t++ = '\\';
		    *t++ = *s;
		}
		break;
	    }
	} else if (fromwhere == 4 && *s == Snull) {
	    for (u = t; (*u++ = *s++););
	    return t + 1;
	} else if (*s == '^' &&
		   (fromwhere == 2 || fromwhere == 5 || fromwhere == 6)) {
	    control = 1;
	    continue;
	} else if (*s == Meta)
	    *t++ = *++s ^ 32;
	else
	    *t++ = *s;
	if (meta == 2) {
	    t[-1] |= 0x80;
	    meta = 0;
	}
	if (control) {
	    if (t[-1] == '?')
		t[-1] = 0x7f;
	    else
		t[-1] &= 0x9f;
	    control = 0;
	}
	if (meta) {
	    t[-1] |= 0x80;
	    meta = 0;
	}
	if (fromwhere == 4 && imeta(t[-1])) {
	    *t = t[-1] ^ 32;
	    t[-1] = Meta;
	    t++;
	}
	if (fromwhere == 6 && t != tmp) {
	    *misc = STOUC(tmp[0]);
	    return s + 1;
	}
    }
    DPUTS(fromwhere == 4, "BUG: unterminated $' substitution");
    *t = '\0';
    *len = t - buf;
    return buf;
}

/* Return non-zero if s is a prefix of t. */

/**/
mod_export int
strpfx(char *s, char *t)
{
    while (*s && *s == *t)
	s++, t++;
    return !*s;
}

/* Return non-zero if s is a suffix of t. */

/**/
mod_export int
strsfx(char *s, char *t)
{
    int ls = strlen(s), lt = strlen(t);

    if (ls <= lt)
	return !strcmp(t + lt - ls, s);
    return 0;
}

/**/
mod_export char *
dupstrpfx(const char *s, int len)
{
    char *r = ncalloc(len + 1);

    memcpy(r, s, len);
    r[len] = '\0';
    return r;
}

/**/
mod_export char *
ztrduppfx(const char *s, int len)
{
    char *r = zalloc(len + 1);

    memcpy(r, s, len);
    r[len] = '\0';
    return r;
}

/* Append a string to an allocated string, reallocating to make room. */

/**/
mod_export char *
appstr(char *base, char const *append)
{
    return strcat(realloc(base, strlen(base) + strlen(append) + 1), append);
}

/**/
static int
upchdir(int n)
{
    char buf[PATH_MAX];
    char *s;
    int err = -1;

    while (n > 0) {
	for (s = buf; s < buf + PATH_MAX - 4 && n--; )
	    *s++ = '.', *s++ = '.', *s++ = '/';
	s[-1] = '\0';
	if (chdir(buf))
	    return err;
	err = -2;
    }
    return 0;
}

/* Change directory, without following symlinks.  Returns 0 on success, -1 *
 * on failure.  Sets errno to ENOTDIR if any symlinks are encountered.  If *
 * fchdir() fails, or the current directory is unreadable, we might end up *
 * in an unwanted directory in case of failure.                            */

/**/
mod_export int
lchdir(char const *path, struct dirsav *d, int hard)
{
    char const *pptr;
    int level;
    struct stat st1;
    struct dirsav ds;
#ifdef HAVE_LSTAT
    char buf[PATH_MAX + 1], *ptr;
    int err;
    struct stat st2;
#endif

    if (!d) {
	ds.ino = ds.dev = 0;
	ds.dirname = NULL;
	ds.dirfd = -1;
	d = &ds;
    }
#ifdef HAVE_LSTAT
    if ((*path == '/' || !hard) &&
	(d != &ds || hard)){
#else
    if (*path == '/') {
#endif
	level = -1;
#ifdef HAVE_FCHDIR
	if (d->dirfd < 0 && (d->dirfd = open(".", O_RDONLY | O_NOCTTY)) < 0 &&
	    zgetdir(d) && *d->dirname != '/')
	    d->dirfd = open("..", O_RDONLY | O_NOCTTY);
#else
	if (!d->dirname)
	    zgetdir(d);
#endif
    } else {
	level = 0;
	if (!d->dev && !d->ino) {
	    stat(".", &st1);
	    d->dev = st1.st_dev;
	    d->ino = st1.st_ino;
	}
    }

#ifdef HAVE_LSTAT
    if (!hard)
#endif
    {
	if (d != &ds) {
	    for (pptr = path; *pptr; level++) {
		while (*pptr && *pptr++ != '/');
		while (*pptr == '/')
		    pptr++;
	    }
	    d->level = level;
	}
	return zchdir((char *) path);
    }
#ifdef HAVE_LSTAT
    if (*path == '/')
	chdir("/");
    for(;;) {
	while(*path == '/')
	    path++;
	if(!*path) {
	    if (d == &ds) {
		zsfree(ds.dirname);
		if (ds.dirfd >=0)
		    close(ds.dirfd);
	    } else
		d->level = level;
	    return 0;
	}
	for(pptr = path; *++pptr && *pptr != '/'; ) ;
	if(pptr - path > PATH_MAX) {
	    err = ENAMETOOLONG;
	    break;
	}
	for(ptr = buf; path != pptr; )
	    *ptr++ = *path++;
	*ptr = 0;
	if(lstat(buf, &st1)) {
	    err = errno;
	    break;
	}
	if(!S_ISDIR(st1.st_mode)) {
	    err = ENOTDIR;
	    break;
	}
	if(chdir(buf)) {
	    err = errno;
	    break;
	}
	if (level >= 0)
	    level++;
	if(lstat(".", &st2)) {
	    err = errno;
	    break;
	}
	if(st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino) {
	    err = ENOTDIR;
	    break;
	}
    }
    if (restoredir(d)) {
	if (d == &ds) {
	    zsfree(ds.dirname);
	    if (ds.dirfd >=0)
		close(ds.dirfd);
	}
	errno = err;
	return -2;
    }
    if (d == &ds) {
	zsfree(ds.dirname);
	if (ds.dirfd >=0)
	    close(ds.dirfd);
    }
    errno = err;
    return -1;
#endif /* HAVE_LSTAT */
}

/**/
mod_export int
restoredir(struct dirsav *d)
{
    int err = 0;
    struct stat sbuf;

    if (d->dirname && *d->dirname == '/')
	return chdir(d->dirname);
#ifdef HAVE_FCHDIR
    if (d->dirfd >= 0) {
	if (!fchdir(d->dirfd)) {
	    if (!d->dirname) {
		return 0;
	    } else if (chdir(d->dirname)) {
		close(d->dirfd);
		d->dirfd = -1;
		err = -2;
	    }
	} else {
	    close(d->dirfd);
	    d->dirfd = err = -1;
	}
    } else
#endif
    if (d->level > 0)
	err = upchdir(d->level);
    else if (d->level < 0)
	err = -1;
    if (d->dev || d->ino) {
	stat(".", &sbuf);
	if (sbuf.st_ino != d->ino || sbuf.st_dev != d->dev)
	    err = -2;
    }
    return err;
}

/* Get a signal number from a string */

/**/
mod_export int
getsignum(char *s)
{
    int x, i;

    /* check for a signal specified by number */
    x = atoi(s);
    if (idigit(*s) && x >= 0 && x < VSIGCOUNT)
	return x;

    /* search for signal by name */
    for (i = 0; i < VSIGCOUNT; i++)
	if (!strcmp(s, sigs[i]))
	    return i;

    /* no matching signal */
    return -1;
}

/* Check whether the shell is running with privileges in effect.  *
 * This is the case if EITHER the euid is zero, OR (if the system *
 * supports POSIX.1e (POSIX.6) capability sets) the process'      *
 * Effective or Inheritable capability sets are non-empty.        */

/**/
int
privasserted(void)
{
    if(!geteuid())
	return 1;
#ifdef HAVE_CAP_GET_PROC
    {
	cap_t caps = cap_get_proc();
	if(caps) {
	    /* POSIX doesn't define a way to test whether a capability set *
	     * is empty or not.  Typical.  I hope this is conforming...    */
	    cap_flag_value_t val;
	    cap_value_t n;
	    for(n = 0; !cap_get_flag(caps, n, CAP_EFFECTIVE, &val); n++)
		if(val ||
		   (!cap_get_flag(caps, n, CAP_INHERITABLE, &val) && val)) {
		    cap_free(caps);
		    return 1;
		}
	    cap_free(caps);
	}
    }
#endif /* HAVE_CAP_GET_PROC */
    return 0;
}

#ifdef DEBUG

/**/
mod_export void
dputs(char *message)
{
    fprintf(stderr, "%s\n", message);
    fflush(stderr);
}

#endif /* DEBUG */

/**/
mod_export int
mode_to_octal(mode_t mode)
{
    int m = 0;

    if(mode & S_ISUID)
	m |= 04000;
    if(mode & S_ISGID)
	m |= 02000;
    if(mode & S_ISVTX)
	m |= 01000;
    if(mode & S_IRUSR)
	m |= 00400;
    if(mode & S_IWUSR)
	m |= 00200;
    if(mode & S_IXUSR)
	m |= 00100;
    if(mode & S_IRGRP)
	m |= 00040;
    if(mode & S_IWGRP)
	m |= 00020;
    if(mode & S_IXGRP)
	m |= 00010;
    if(mode & S_IROTH)
	m |= 00004;
    if(mode & S_IWOTH)
	m |= 00002;
    if(mode & S_IXOTH)
	m |= 00001;
    return m;
}

#ifdef MAILDIR_SUPPORT
/*
 *     Stat a file. If it's a maildir, check all messages
 *     in the maildir and present the grand total as a file.
 *     The fields in the 'struct stat' are from the mail directory.
 *     The following fields are emulated:
 *
 *     st_nlink        always 1
 *     st_size         total number of bytes in all files
 *     st_blocks       total number of messages
 *     st_atime        access time of newest file in maildir
 *     st_mtime        modify time of newest file in maildir
 *     st_mode         S_IFDIR changed to S_IFREG
 *
 *     This is good enough for most mail-checking applications.
 */
int
mailstat(char *path, struct stat *st)
{
       DIR                     *dd;
       struct                  dirent *fn;
       struct stat             st_ret, st_tmp;
       static struct stat      st_new_last, st_ret_last;
       char                    dir[PATH_MAX * 2];
       char                    file[PATH_MAX * 2];
       int                     i, l;
       time_t                  atime = 0, mtime = 0;

       /* First see if it's a directory. */
       if ((i = stat(path, st)) != 0 || !S_ISDIR(st->st_mode))
               return i;
       if (strlen(path) > sizeof(dir) - 5) {
               errno = ENAMETOOLONG;
               return -1;
       }

       st_ret = *st;
       st_ret.st_nlink = 1;
       st_ret.st_size  = 0;
       st_ret.st_blocks  = 0;
       st_ret.st_mode  &= ~S_IFDIR;
       st_ret.st_mode  |= S_IFREG;

       /* See if cur/ is present */
       sprintf(dir, "%s/cur", path);
       if (stat(dir, &st_tmp) || !S_ISDIR(st_tmp.st_mode)) return 0;
       st_ret.st_atime = st_tmp.st_atime;

       /* See if tmp/ is present */
       sprintf(dir, "%s/tmp", path);
       if (stat(dir, &st_tmp) || !S_ISDIR(st_tmp.st_mode)) return 0;
       st_ret.st_mtime = st_tmp.st_mtime;

       /* And new/ */
       sprintf(dir, "%s/new", path);
       if (stat(dir, &st_tmp) || !S_ISDIR(st_tmp.st_mode)) return 0;
       st_ret.st_mtime = st_tmp.st_mtime;

       /* Optimization - if new/ didn't change, nothing else did. */
       if (st_tmp.st_dev == st_new_last.st_dev &&
           st_tmp.st_ino == st_new_last.st_ino &&
           st_tmp.st_atime == st_new_last.st_atime &&
           st_tmp.st_mtime == st_new_last.st_mtime) {
               *st = st_ret_last;
               return 0;
       }
       st_new_last = st_tmp;

       /* Loop over new/ and cur/ */
       for (i = 0; i < 2; i++) {
               sprintf(dir, "%s/%s", path, i ? "cur" : "new");
               sprintf(file, "%s/", dir);
               l = strlen(file);
               if ((dd = opendir(dir)) == NULL)
                       return 0;
               while ((fn = readdir(dd)) != NULL) {
                       if (fn->d_name[0] == '.' ||
                           strlen(fn->d_name) + l >= sizeof(file))
                               continue;
                       strcpy(file + l, fn->d_name);
                       if (stat(file, &st_tmp) != 0)
                               continue;
                       st_ret.st_size += st_tmp.st_size;
                       st_ret.st_blocks++;
                       if (st_tmp.st_atime != st_tmp.st_mtime &&
                           st_tmp.st_atime > atime)
                               atime = st_tmp.st_atime;
                       if (st_tmp.st_mtime > mtime)
                               mtime = st_tmp.st_mtime;
               }
               closedir(dd);
       }

       if (atime) st_ret.st_atime = atime;
       if (mtime) st_ret.st_mtime = mtime;

       *st = st_ret_last = st_ret;
       return 0;
}
#endif