Return to left.c CVS log

Up to [CSRG BSD Unix] / 43BSD / contrib / icon / functions

Annotation of 43BSD/contrib/icon/functions/left.c, revision 1.1

1.1     ! root        1: #include "../h/rt.h"
        !             2: 
        !             3: /*
        !             4:  * left(s1,n,s2) - pad s1 on right with s2 to length n.
        !             5:  */
        !             6: 
        !             7: Xleft(nargs, arg3, arg2, arg1, arg0)
        !             8: int nargs;
        !             9: struct descrip arg3, arg2, arg1, arg0;
        !            10:    {
        !            11:    register char *s, *st;
        !            12:    int cnt, slen;
        !            13:    char *sbuf, *s3, sbuf1[MAXSTRING], sbuf2[MAXSTRING];
        !            14:    extern char *alcstr();
        !            15: 
        !            16:    /*
        !            17:     * s1 must be a string.  n must be a non-negative integer and defaults
        !            18:     *  to 1.  s2 must be a string and defaults to a blank.
        !            19:     */
        !            20:    if (cvstr(&arg1, sbuf1) == NULL)
        !            21:       runerr(103, &arg1);
        !            22:    defshort(&arg2, 1);
        !            23:    if ((cnt = INTVAL(arg2)) < 0)
        !            24:       runerr(205, &arg2);
        !            25:    defstr(&arg3, sbuf2, &blank);
        !            26: 
        !            27:    sneed(cnt);
        !            28:    if (STRLEN(arg3) == 0) {
        !            29:       /*
        !            30:        * The padding string is null, make it a blank.
        !            31:        */
        !            32:       slen = 1;
        !            33:       s3 = " ";
        !            34:       }
        !            35:    else {
        !            36:       slen = STRLEN(arg3);
        !            37:       s3 = STRLOC(arg3);
        !            38:       }
        !            39: 
        !            40:    /*
        !            41:     * Get n bytes of string space.  Start at the right end of the new
        !            42:     *  string and copy s2 into the new string as many times as it fits.
        !            43:     *  Note that s2 is copied from right to left.
        !            44:     */
        !            45:    sbuf = alcstr(NULL, cnt);
        !            46:    s = sbuf + cnt;
        !            47:    while (s > sbuf) {
        !            48:       st = s3 + slen;
        !            49:       while (st > s3 && s > sbuf)
        !            50:          *--s = *--st;
        !            51:       }
        !            52: 
        !            53:    /*
        !            54:     * Copy s1 into the new string, starting at the left end.  If *s1 > n,
        !            55:     *  only copy n bytes.
        !            56:     */
        !            57:    s = sbuf;
        !            58:    slen = STRLEN(arg1);
        !            59:    st = STRLOC(arg1);
        !            60:    if (slen > cnt)
        !            61:       slen = cnt;
        !            62:    while (slen-- > 0)
        !            63:       *s++ = *st++;
        !            64: 
        !            65:    /*
        !            66:     * Return the new string.
        !            67:     */
        !            68:    STRLEN(arg0) = cnt;
        !            69:    STRLOC(arg0) = sbuf;
        !            70:    }
        !            71: 
        !            72: Procblock(left,3)

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.