// loop.c - loop execution

//

// © Portions Copyright (c) Symbian Software Ltd 2007. All rights reserved.

//

/*

 * 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 "loop.pro"

#ifdef __SYMBIAN32__

#ifdef __WINSCW__

#pragma warn_unusedarg off

#pragma warn_possunwant off

#endif//__WINSCW__

#endif//__SYMBIAN32__

/* # of nested loops we are in */

/**/

int loops;

/* # of continue levels */

/**/

mod_export int contflag;

/* # of break levels */

/**/

mod_export int breaks;

/**/

int

execfor(Estate state, int do_exec)

{

    Wordcode end, loop;

    wordcode code = state->pc[-1];

    int iscond = (WC_FOR_TYPE(code) == WC_FOR_COND), ctok = 0, atok = 0;

    int last = 0;

    char *name, *str, *cond = NULL, *advance = NULL;

    zlong val = 0;

    LinkList vars = NULL, args = NULL;

    end = state->pc + WC_FOR_SKIP(code);

    if (iscond) {

	str = dupstring(ecgetstr(state, EC_NODUP, NULL));

	singsub(&str);

	if (isset(XTRACE)) {

	    char *str2 = dupstring(str);

	    untokenize(str2);

	    printprompt4();

	    fprintf(xtrerr, "%s\n", str2);

	    fflush(xtrerr);

	}

	if (!errflag)

	    matheval(str);

	if (errflag) {

	    state->pc = end;

	    return lastval = errflag;

	}

	cond = ecgetstr(state, EC_NODUP, &ctok);

	advance = ecgetstr(state, EC_NODUP, &atok);

    } else {

	vars = ecgetlist(state, *state->pc++, EC_NODUP, NULL);

	if (WC_FOR_TYPE(code) == WC_FOR_LIST) {

	    int htok = 0;

	    if (!(args = ecgetlist(state, *state->pc++, EC_DUPTOK, &htok))) {

		state->pc = end;

		return 0;

	    }

	    if (htok)

		execsubst(args);

	} else {

	    char **x;

	    args = newlinklist();

	    for (x = pparams; *x; x++)

		addlinknode(args, dupstring(*x));

	}

    }

    lastval = 0;

    loops++;

    pushheap();

    cmdpush(CS_FOR);

    loop = state->pc;

    while (!last) {

	if (iscond) {

	    if (ctok) {

		str = dupstring(cond);

		singsub(&str);

	    } else

		str = cond;

	    if (!errflag) {

		while (iblank(*str))

		    str++;

		if (*str) {

		    if (isset(XTRACE)) {

			printprompt4();

			fprintf(xtrerr, "%s\n", str);

			fflush(xtrerr);

		    }

		    val = mathevali(str);

		} else

		    val = 1;

	    }

	    if (errflag) {

		if (breaks)

		    breaks--;

		lastval = 1;

		break;

	    }

	    if (!val)

		break;

	} else {

	    LinkNode node;

	    int count = 0;

	    for (node = firstnode(vars); node; incnode(node))

	    {

		name = (char *)getdata(node);

		if (!args || !(str = (char *) ugetnode(args)))

		{

		    if (count) { 

			str = "";

			last = 1;

		    } else

			break;

		}

		if (isset(XTRACE)) {

		    printprompt4();

		    fprintf(xtrerr, "%s=%s\n", name, str);

		    fflush(xtrerr);

		}

		setsparam(name, ztrdup(str));

		count++;

	    }

	    if (!count)

		break;

	}

	state->pc = loop;

	execlist(state, 1, do_exec && args && empty(args));

	if (breaks) {

	    breaks--;

	    if (breaks || !contflag)

		break;

	    contflag = 0;

	}

	if (retflag)

	    break;

	if (iscond && !errflag) {

	    if (atok) {

		str = dupstring(advance);

		singsub(&str);

	    } else

		str = advance;

	    if (isset(XTRACE)) {

		printprompt4();

		fprintf(xtrerr, "%s\n", str);

		fflush(xtrerr);

	    }

	    if (!errflag)

		matheval(str);

	}

	if (errflag) {

	    if (breaks)

		breaks--;

	    lastval = 1;

	    break;

	}

	freeheap();

    }

    popheap();

    cmdpop();

    loops--;

    state->pc = end;

    return lastval;

}

/**/

int

execselect(Estate state, UNUSED(int do_exec))

{

    Wordcode end, loop;

    wordcode code = state->pc[-1];

    char *str, *s, *name;

    LinkNode n;

    int i, usezle;

    FILE *inp;

    size_t more;

    LinkList args;

    end = state->pc + WC_FOR_SKIP(code);

    name = ecgetstr(state, EC_NODUP, NULL);

    if (WC_SELECT_TYPE(code) == WC_SELECT_PPARAM) {

	char **x;

	args = newlinklist();

	for (x = pparams; *x; x++)

	    addlinknode(args, dupstring(*x));

    } else {

	int htok = 0;

	if (!(args = ecgetlist(state, *state->pc++, EC_DUPTOK, &htok))) {

	    state->pc = end;

	    return 0;

	}

	if (htok)

	    execsubst(args);

    }

    if (!args || empty(args)) {

	state->pc = end;

	return 1;

    }

    loops++;

    lastval = 0;

    pushheap();

    cmdpush(CS_SELECT);

    usezle = interact && SHTTY != -1 && isset(USEZLE);

    inp = fdopen(dup(usezle ? SHTTY : 0), "r");

    more = selectlist(args, 0);

    loop = state->pc;

    for (;;) {

	for (;;) {

	    if (empty(bufstack)) {

	    	if (usezle) {

		    int oef = errflag;

		    isfirstln = 1;

		    str = (char *)zleread(&prompt3, NULL, 0, ZLCON_SELECT);

		    if (errflag)

			str = NULL;

		    errflag = oef;

	    	} else {

		    str = promptexpand(prompt3, 0, NULL, NULL);

		    zputs(str, stderr);

		    free(str);

		    fflush(stderr);

		    str = fgets(zalloc(256), 256, inp);

	    	}

	    } else

		str = (char *)getlinknode(bufstack);

	    if (!str || errflag) {

		if (breaks)

		    breaks--;

		fprintf(stderr, "\n");

		fflush(stderr);

		goto done;

	    }

	    if ((s = strchr(str, '\n')))

		*s = '\0';

	    if (*str)

	      break;

	    more = selectlist(args, more);

	}

	setsparam("REPLY", ztrdup(str));

	i = atoi(str);

	if (!i)

	    str = "";

	else {

	    for (i--, n = firstnode(args); n && i; incnode(n), i--);

	    if (n)

		str = (char *) getdata(n);

	    else

		str = "";

	}

	setsparam(name, ztrdup(str));

	state->pc = loop;

	execlist(state, 1, 0);

	freeheap();

	if (breaks) {

	    breaks--;

	    if (breaks || !contflag)

		break;

	    contflag = 0;

	}

	if (retflag || errflag)

	    break;

    }

  done:

    cmdpop();

    popheap();

    fclose(inp);

    loops--;

    state->pc = end;

    return lastval;

}

/* And this is used to print select lists. */

/**/

size_t

selectlist(LinkList l, size_t start)

{

    size_t longest = 1, fct, fw = 0, colsz, t0, t1, ct;

    LinkNode n;

    char **arr, **ap;

    trashzle();

    ct = countlinknodes(l);

    ap = arr = (char **) zhalloc((countlinknodes(l) + 1) * sizeof(char **));

    for (n = (LinkNode) firstnode(l); n; incnode(n))

	*ap++ = (char *)getdata(n);

    *ap = NULL;

    for (ap = arr; *ap; ap++)

	if (strlen(*ap) > longest)

	    longest = strlen(*ap);

    t0 = ct;

    longest++;

    while (t0)

	t0 /= 10, longest++;

    /* to compensate for added ')' */

    fct = (columns - 1) / (longest + 3);

    if (fct == 0)

	fct = 1;

    else

	fw = (columns - 1) / fct;

    colsz = (ct + fct - 1) / fct;

    for (t1 = start; t1 != colsz && t1 - start < lines - 2; t1++) {

	ap = arr + t1;

	do {

	    size_t t2 = strlen(*ap) + 2;

	    int t3;

	    fprintf(stderr, "%d) %s", t3 = ap - arr + 1, *ap);

	    while (t3)

		t2++, t3 /= 10;

	    for (; t2 < fw; t2++)

		fputc(' ', stderr);

	    for (t0 = colsz; t0 && *ap; t0--, ap++);

	}

	while (*ap);

	fputc('\n', stderr);

    }

 /* Below is a simple attempt at doing it the Korn Way..

       ap = arr;

       t0 = 0;

       do {

           t0++;

           fprintf(stderr,"%d) %s\n",t0,*ap);

           ap++;

       }

       while (*ap);*/

    fflush(stderr);

    return t1 < colsz ? t1 : 0;

}

/**/

int

execwhile(Estate state, UNUSED(int do_exec))

{

    Wordcode end, loop;

    wordcode code = state->pc[-1];

    int olderrexit, oldval, isuntil = (WC_WHILE_TYPE(code) == WC_WHILE_UNTIL);

    end = state->pc + WC_WHILE_SKIP(code);

    olderrexit = noerrexit;

    oldval = 0;

    pushheap();

    cmdpush(isuntil ? CS_UNTIL : CS_WHILE);

    loops++;

    loop = state->pc;

    if (loop[0] == WC_END && loop[1] == WC_END) {

        /* This is an empty loop.  Make sure the signal handler sets the

        * flags and then just wait for someone hitting ^C. */

        int old_simple_pline = simple_pline;

        simple_pline = 1;

        while (!breaks)

            ;

        breaks--;

        simple_pline = old_simple_pline;

    } else

        for (;;) {

            state->pc = loop;

            noerrexit = 1;

            execlist(state, 1, 0);

            noerrexit = olderrexit;

            if (!((lastval == 0) ^ isuntil)) {

                if (breaks)

                    breaks--;

                lastval = oldval;

                break;

            }

            if (retflag) {

                lastval = oldval;

                break;

            }

            execlist(state, 1, 0);

            if (breaks) {

                breaks--;

                if (breaks || !contflag)

                    break;

                contflag = 0;

            }

            if (errflag) {

                lastval = 1;

                break;

            }

            if (retflag)

                break;

            freeheap();

            oldval = lastval;

        }

    cmdpop();

    popheap();

    loops--;

    state->pc = end;

    return lastval;

}

/**/

int

execrepeat(Estate state, UNUSED(int do_exec))

{

    Wordcode end, loop;

    wordcode code = state->pc[-1];

    int count, htok = 0;

    char *tmp;

    end = state->pc + WC_REPEAT_SKIP(code);

    lastval = 0;

    tmp = ecgetstr(state, EC_DUPTOK, &htok);

    if (htok)

	singsub(&tmp);

    count = atoi(tmp);

    pushheap();

    cmdpush(CS_REPEAT);

    loops++;

    loop = state->pc;

    while (count-- > 0) {

	state->pc = loop;

	execlist(state, 1, 0);

	freeheap();

	if (breaks) {

	    breaks--;

	    if (breaks || !contflag)

		break;

	    contflag = 0;

	}

	if (errflag) {

	    lastval = 1;

	    break;

	}

	if (retflag)

	    break;

    }

    cmdpop();

    popheap();

    loops--;

    state->pc = end;

    return lastval;

}

/**/

int

execif(Estate state, int do_exec)

{

    Wordcode end, next;

    wordcode code = state->pc[-1];

    int olderrexit, s = 0, run = 0;

    olderrexit = noerrexit;

    end = state->pc + WC_IF_SKIP(code);

    if (!noerrexit)

	noerrexit = 1;

    while (state->pc < end) {

	code = *state->pc++;

	if (wc_code(code) != WC_IF ||

	    (run = (WC_IF_TYPE(code) == WC_IF_ELSE))) {

	    if (run)

		run = 2;

	    break;

	}

	next = state->pc + WC_IF_SKIP(code);

	cmdpush(s ? CS_ELIF : CS_IF);

	execlist(state, 1, 0);

	cmdpop();

	if (!lastval) {

	    run = 1;

	    break;

	}

	if (retflag)

	    break;

	s = 1;

	state->pc = next;

    }

    noerrexit = olderrexit;

    if (run) {

	cmdpush(run == 2 ? CS_ELSE : (s ? CS_ELIFTHEN : CS_IFTHEN));

	execlist(state, 1, do_exec);