diff options
Diffstat (limited to 'contrib/nvi/ex/ex_shift.c')
| -rw-r--r-- | contrib/nvi/ex/ex_shift.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/contrib/nvi/ex/ex_shift.c b/contrib/nvi/ex/ex_shift.c new file mode 100644 index 0000000..83bd36d --- /dev/null +++ b/contrib/nvi/ex/ex_shift.c @@ -0,0 +1,191 @@ +/*- + * 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_shift.c 10.11 (Berkeley) 9/15/96"; +#endif /* not lint */ + +#include <sys/types.h> +#include <sys/queue.h> + +#include <bitstring.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "../common/common.h" + +enum which {LEFT, RIGHT}; +static int shift __P((SCR *, EXCMD *, enum which)); + +/* + * ex_shiftl -- :<[<...] + * + * + * PUBLIC: int ex_shiftl __P((SCR *, EXCMD *)); + */ +int +ex_shiftl(sp, cmdp) + SCR *sp; + EXCMD *cmdp; +{ + return (shift(sp, cmdp, LEFT)); +} + +/* + * ex_shiftr -- :>[>...] + * + * PUBLIC: int ex_shiftr __P((SCR *, EXCMD *)); + */ +int +ex_shiftr(sp, cmdp) + SCR *sp; + EXCMD *cmdp; +{ + return (shift(sp, cmdp, RIGHT)); +} + +/* + * shift -- + * Ex shift support. + */ +static int +shift(sp, cmdp, rl) + SCR *sp; + EXCMD *cmdp; + enum which rl; +{ + recno_t from, to; + size_t blen, len, newcol, newidx, oldcol, oldidx, sw; + int curset; + char *p, *bp, *tbp; + + NEEDFILE(sp, cmdp); + + if (O_VAL(sp, O_SHIFTWIDTH) == 0) { + msgq(sp, M_INFO, "152|shiftwidth option set to 0"); + return (0); + } + + /* Copy the lines being shifted into the unnamed buffer. */ + if (cut(sp, NULL, &cmdp->addr1, &cmdp->addr2, CUT_LINEMODE)) + return (1); + + /* + * The historic version of vi permitted the user to string any number + * of '>' or '<' characters together, resulting in an indent of the + * appropriate levels. There's a special hack in ex_cmd() so that + * cmdp->argv[0] points to the string of '>' or '<' characters. + * + * Q: What's the difference between the people adding features + * to vi and the Girl Scouts? + * A: The Girl Scouts have mint cookies and adult supervision. + */ + for (p = cmdp->argv[0]->bp, sw = 0; *p == '>' || *p == '<'; ++p) + sw += O_VAL(sp, O_SHIFTWIDTH); + + GET_SPACE_RET(sp, bp, blen, 256); + + curset = 0; + for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) { + if (db_get(sp, from, DBG_FATAL, &p, &len)) + goto err; + if (!len) { + if (sp->lno == from) + curset = 1; + continue; + } + + /* + * Calculate the old indent amount and the number of + * characters it used. + */ + for (oldidx = 0, oldcol = 0; oldidx < len; ++oldidx) + if (p[oldidx] == ' ') + ++oldcol; + else if (p[oldidx] == '\t') + oldcol += O_VAL(sp, O_TABSTOP) - + oldcol % O_VAL(sp, O_TABSTOP); + else + break; + + /* Calculate the new indent amount. */ + if (rl == RIGHT) + newcol = oldcol + sw; + else { + newcol = oldcol < sw ? 0 : oldcol - sw; + if (newcol == oldcol) { + if (sp->lno == from) + curset = 1; + continue; + } + } + + /* Get a buffer that will hold the new line. */ + ADD_SPACE_RET(sp, bp, blen, newcol + len); + + /* + * Build a new indent string and count the number of + * characters it uses. + */ + for (tbp = bp, newidx = 0; + newcol >= O_VAL(sp, O_TABSTOP); ++newidx) { + *tbp++ = '\t'; + newcol -= O_VAL(sp, O_TABSTOP); + } + for (; newcol > 0; --newcol, ++newidx) + *tbp++ = ' '; + + /* Add the original line. */ + memcpy(tbp, p + oldidx, len - oldidx); + + /* Set the replacement line. */ + if (db_set(sp, from, bp, (tbp + (len - oldidx)) - bp)) { +err: FREE_SPACE(sp, bp, blen); + return (1); + } + + /* + * !!! + * The shift command in historic vi had the usual bizarre + * collection of cursor semantics. If called from vi, the + * cursor was repositioned to the first non-blank character + * of the lowest numbered line shifted. If called from ex, + * the cursor was repositioned to the first non-blank of the + * highest numbered line shifted. Here, if the cursor isn't + * part of the set of lines that are moved, move it to the + * first non-blank of the last line shifted. (This makes + * ":3>>" in vi work reasonably.) If the cursor is part of + * the shifted lines, it doesn't get moved at all. This + * permits shifting of marked areas, i.e. ">'a." shifts the + * marked area twice, something that couldn't be done with + * historic vi. + */ + if (sp->lno == from) { + curset = 1; + if (newidx > oldidx) + sp->cno += newidx - oldidx; + else if (sp->cno >= oldidx - newidx) + sp->cno -= oldidx - newidx; + } + } + if (!curset) { + sp->lno = to; + sp->cno = 0; + (void)nonblank(sp, to, &sp->cno); + } + + FREE_SPACE(sp, bp, blen); + + sp->rptlines[L_SHIFT] += cmdp->addr2.lno - cmdp->addr1.lno + 1; + return (0); +} |
