cmd/csh/sh.hist.c

	sh.hist.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * Copyright 1990 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley Software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "sh.h"
#include "sh.tconst.h"

/*
 * C shell
 */

savehist(sp)
    struct wordent *sp;
{
    register struct Hist *hp, *np;
    register int histlen = 0;
    tchar *cp;

#ifdef TRACE
    tprintf("TRACE- savehist()\n");
#endif
    /* throw away null lines */
    if (sp->next->word[0] == '\n')
        return;
    cp = value(S_history /*"history"*/);
    if (*cp) {
        register tchar *p = cp;

        while (*p) {
            if (!digit(*p)) {
                histlen = 0;
                break;
            }
            histlen = histlen * 10 + *p++ - '0';
        }
    }
    for (hp = &Histlist; np = hp->Hnext;)
        if (eventno - np->Href >= histlen || histlen == 0)
            hp->Hnext = np->Hnext, hfree(np);
        else
            hp = np;
    (void) enthist(++eventno, sp, 1);
}

struct Hist *
enthist(event, lp, docopy)
    int event;
    register struct wordent *lp;
    bool docopy;
{
    register struct Hist *np;

#ifdef TRACE
    tprintf("TRACE- enthist()\n");
#endif
    np = (struct Hist *) xalloc(sizeof *np);
    np->Hnum = np->Href = event;
    if (docopy)
        copylex(&np->Hlex, lp);
    else {
        np->Hlex.next = lp->next;
        lp->next->prev = &np->Hlex;
        np->Hlex.prev = lp->prev;
        lp->prev->next = &np->Hlex;
    }
    np->Hnext = Histlist.Hnext;
    Histlist.Hnext = np;
    return (np);
}

hfree(hp)
    register struct Hist *hp;
{
#ifdef TRACE
    tprintf("TRACE- hfree()\n");
#endif

    freelex(&hp->Hlex);
    xfree( (tchar *)hp);
}

dohist(vp)
    tchar **vp;
{
    int n, rflg = 0, hflg = 0;
#ifdef TRACE
    tprintf("TRACE- dohist()\n");
#endif
    if (getn(value(S_history /*"history"*/)) == 0)
        return;
    if (setintr)
        (void) sigsetmask(sigblock(0) & ~sigmask(SIGINT));
    while (*++vp && **vp == '-') {
        tchar *vp2 = *vp;

        while (*++vp2)
            switch (*vp2) {
            case 'h':
                hflg++;
                break;
            case 'r':
                rflg++;
                break;
            case '-':   /* ignore multiple '-'s */
                break;
            default:
                printf("Unknown flag: -%c\n", *vp2);
                error("Usage: history [-rh] [# number of events]");
            }
    }
    if (*vp)
        n = getn(*vp);
    else {
        n = getn(value(S_history /*"history"*/));
    }
    dohist1(Histlist.Hnext, &n, rflg, hflg);
}

dohist1(hp, np, rflg, hflg)
    struct Hist *hp;
    int *np, rflg, hflg;
{
    bool print = (*np) > 0;
#ifdef TRACE
    tprintf("TRACE- dohist1()\n");
#endif
top:
    if (hp == 0)
        return;
    (*np)--;
    hp->Href++;
    if (rflg == 0) {
        dohist1(hp->Hnext, np, rflg, hflg);
        if (print)
            phist(hp, hflg);
        return;
    }
    if (*np >= 0)
        phist(hp, hflg);
    hp = hp->Hnext;
    goto top;
}

phist(hp, hflg)
    register struct Hist *hp;
    int hflg;
{
#ifdef TRACE
    tprintf("TRACE- phist()\n");
#endif

    if (hflg == 0)
        printf("%6d\t", hp->Hnum);
    prlex(&hp->Hlex);
}