diff options
Diffstat (limited to 'ex/ex_z.c')
| -rw-r--r-- | ex/ex_z.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/ex/ex_z.c b/ex/ex_z.c new file mode 100644 index 000000000000..41b72ad1fd42 --- /dev/null +++ b/ex/ex_z.c @@ -0,0 +1,150 @@ +/*- + * Copyright (c) 1993, 1994 + * The Regents of the University of California. All rights reserved. + * Copyright (c) 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_z.c 10.10 (Berkeley) 3/6/96"; +#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" + +/* + * ex_z -- :[line] z [^-.+=] [count] [flags] + * Adjust window. + * + * PUBLIC: int ex_z __P((SCR *, EXCMD *)); + */ +int +ex_z(sp, cmdp) + SCR *sp; + EXCMD *cmdp; +{ + MARK abs; + recno_t cnt, equals, lno; + int eofcheck; + + NEEDFILE(sp, cmdp); + + /* + * !!! + * If no count specified, use either two times the size of the + * scrolling region, or the size of the window option. POSIX + * 1003.2 claims that the latter is correct, but historic ex/vi + * documentation and practice appear to use the scrolling region. + * I'm using the window size as it means that the entire screen + * is used instead of losing a line to roundoff. Note, we drop + * a line from the cnt if using the window size to leave room for + * the next ex prompt. + */ + if (FL_ISSET(cmdp->iflags, E_C_COUNT)) + cnt = cmdp->count; + else +#ifdef HISTORIC_PRACTICE + cnt = O_VAL(sp, O_SCROLL) * 2; +#else + cnt = O_VAL(sp, O_WINDOW) - 1; +#endif + + equals = 0; + eofcheck = 0; + lno = cmdp->addr1.lno; + + switch (FL_ISSET(cmdp->iflags, + E_C_CARAT | E_C_DASH | E_C_DOT | E_C_EQUAL | E_C_PLUS)) { + case E_C_CARAT: /* Display cnt * 2 before the line. */ + eofcheck = 1; + if (lno > cnt * 2) + cmdp->addr1.lno = (lno - cnt * 2) + 1; + else + cmdp->addr1.lno = 1; + cmdp->addr2.lno = (cmdp->addr1.lno + cnt) - 1; + break; + case E_C_DASH: /* Line goes at the bottom of the screen. */ + cmdp->addr1.lno = lno > cnt ? (lno - cnt) + 1 : 1; + cmdp->addr2.lno = lno; + break; + case E_C_DOT: /* Line goes in the middle of the screen. */ + /* + * !!! + * Historically, the "middleness" of the line overrode the + * count, so that "3z.19" or "3z.20" would display the first + * 12 lines of the file, i.e. (N - 1) / 2 lines before and + * after the specified line. + */ + eofcheck = 1; + cnt = (cnt - 1) / 2; + cmdp->addr1.lno = lno > cnt ? lno - cnt : 1; + cmdp->addr2.lno = lno + cnt; + + /* + * !!! + * Historically, z. set the absolute cursor mark. + */ + abs.lno = sp->lno; + abs.cno = sp->cno; + (void)mark_set(sp, ABSMARK1, &abs, 1); + break; + case E_C_EQUAL: /* Center with hyphens. */ + /* + * !!! + * Strangeness. The '=' flag is like the '.' flag (see the + * above comment, it applies here as well) but with a special + * little hack. Print out lines of hyphens before and after + * the specified line. Additionally, the cursor remains set + * on that line. + */ + eofcheck = 1; + cnt = (cnt - 1) / 2; + cmdp->addr1.lno = lno > cnt ? lno - cnt : 1; + cmdp->addr2.lno = lno - 1; + if (ex_pr(sp, cmdp)) + return (1); + (void)ex_puts(sp, "----------------------------------------\n"); + cmdp->addr2.lno = cmdp->addr1.lno = equals = lno; + if (ex_pr(sp, cmdp)) + return (1); + (void)ex_puts(sp, "----------------------------------------\n"); + cmdp->addr1.lno = lno + 1; + cmdp->addr2.lno = (lno + cnt) - 1; + break; + default: + /* If no line specified, move to the next one. */ + if (F_ISSET(cmdp, E_ADDR_DEF)) + ++lno; + /* FALLTHROUGH */ + case E_C_PLUS: /* Line goes at the top of the screen. */ + eofcheck = 1; + cmdp->addr1.lno = lno; + cmdp->addr2.lno = (lno + cnt) - 1; + break; + } + + if (eofcheck) { + if (db_last(sp, &lno)) + return (1); + if (cmdp->addr2.lno > lno) + cmdp->addr2.lno = lno; + } + + if (ex_pr(sp, cmdp)) + return (1); + if (equals) + sp->lno = equals; + return (0); +} |