OS/2 Spezial/SPEZIAL2_97.zip/SPEZIAL2_97.iso/ANWEND/EDITOR/NVI179B/NVI179B.ZIP/ex/ex_join.c

C/C++ Source or Header | 1996-09-15 | 5KB | 178 lines

/*-
 * Copyright (c) 1992, 1993, 1994
 *    The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1992, 1993, 1994, 1995, 1996
 *    Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 */

#include "config.h"

#ifndef lint
static const char sccsid[] = "@(#)ex_join.c    10.10 (Berkeley) 9/15/96";
#endif /* not lint */

#include <sys/types.h>
#include <sys/queue.h>

#include <bitstring.h>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "../common/common.h"

/*
 * ex_join -- :[line [,line]] j[oin][!] [count] [flags]
 *    Join lines.
 *
 * PUBLIC: int ex_join __P((SCR *, EXCMD *));
 */
int
ex_join(sp, cmdp)
    SCR *sp;
    EXCMD *cmdp;
{
    recno_t from, to;
    size_t blen, clen, len, tlen;
    int echar, extra, first;
    char *bp, *p, *tbp;

    NEEDFILE(sp, cmdp);

    from = cmdp->addr1.lno;
    to = cmdp->addr2.lno;

    /* Check for no lines to join. */
    if (!db_exist(sp, from + 1)) {
        msgq(sp, M_ERR, "131|No following lines to join");
        return (1);
    }

    GET_SPACE_RET(sp, bp, blen, 256);

    /*
     * The count for the join command was off-by-one,
     * historically, to other counts for other commands.
     */
    if (FL_ISSET(cmdp->iflags, E_C_COUNT))
        ++cmdp->addr2.lno;

    /*
     * If only a single address specified, or, the same address
     * specified twice, the from/two addresses will be the same.
     */
    if (cmdp->addr1.lno == cmdp->addr2.lno)
        ++cmdp->addr2.lno;

    clen = tlen = 0;
        for (first = 1,
        from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) {
        /*
         * Get next line.  Historic versions of vi allowed "10J" while
         * less than 10 lines from the end-of-file, so we do too.
         */
        if (db_get(sp, from, 0, &p, &len)) {
            cmdp->addr2.lno = from - 1;
            break;
        }

        /* Empty lines just go away. */
        if (len == 0)
            continue;

        /*
         * Get more space if necessary.  Note, tlen isn't the length
         * of the new line, it's roughly the amount of space needed.
         * tbp - bp is the length of the new line.
         */
        tlen += len + 2;
        ADD_SPACE_RET(sp, bp, blen, tlen);
        tbp = bp + clen;

        /*
         * Historic practice:
         *
         * If force specified, join without modification.
         * If the current line ends with whitespace, strip leading
         *    whitespace from the joined line.
         * If the next line starts with a ), do nothing.
         * If the current line ends with ., insert two spaces.
         * Else, insert one space.
         *
         * One change -- add ? and ! to the list of characters for
         * which we insert two spaces.  I expect that POSIX 1003.2
         * will require this as well.
         *
         * Echar is the last character in the last line joined.
         */
        extra = 0;
        if (!first && !FL_ISSET(cmdp->iflags, E_C_FORCE)) {
            if (isblank(echar))
                for (; len && isblank(*p); --len, ++p);
            else if (p[0] != ')') {
                if (strchr(".?!", echar)) {
                    *tbp++ = ' ';
                    ++clen;
                    extra = 1;
                }
                *tbp++ = ' ';
                ++clen;
                for (; len && isblank(*p); --len, ++p);
            }
        }

        if (len != 0) {
            memcpy(tbp, p, len);
            tbp += len;
            clen += len;
            echar = p[len - 1];
        } else
            echar = ' ';

        /*
         * Historic practice for vi was to put the cursor at the first
         * inserted whitespace character, if there was one, or the
         * first character of the joined line, if there wasn't, or the
         * last character of the line if joined to an empty line.  If
         * a count was specified, the cursor was moved as described
         * for the first line joined, ignoring subsequent lines.  If
         * the join was a ':' command, the cursor was placed at the
         * first non-blank character of the line unless the cursor was
         * "attracted" to the end of line when the command was executed
         * in which case it moved to the new end of line.  There are
         * probably several more special cases, but frankly, my dear,
         * I don't give a damn.  This implementation puts the cursor
         * on the first inserted whitespace character, the first
         * character of the joined line, or the last character of the
         * line regardless.  Note, if the cursor isn't on the joined
         * line (possible with : commands), it is reset to the starting
         * line.
         */
        if (first) {
            sp->cno = (tbp - bp) - (1 + extra);
            first = 0;
        } else
            sp->cno = (tbp - bp) - len - (1 + extra);
    }
    sp->lno = cmdp->addr1.lno;

    /* Delete the joined lines. */
        for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; to > from; --to)
        if (db_delete(sp, to))
            goto err;

    /* If the original line changed, reset it. */
    if (!first && db_set(sp, from, bp, tbp - bp)) {
err:        FREE_SPACE(sp, bp, blen);
        return (1);
    }
    FREE_SPACE(sp, bp, blen);

    sp->rptlines[L_JOINED] += (cmdp->addr2.lno - cmdp->addr1.lno) + 1;
    return (0);
}