freebsd-dev/contrib/nvi/vi/vs_line.c
Peter Wemm b8ba871bd9 Import of nvi-1.79, minus a few bits that we dont need (eg: postscript
files, curses, db, regex etc that we already have).  The other glue will
follow shortly.

Obtained from: Keith Bostic <bostic@bostic.com>
1996-11-01 06:45:43 +00:00

515 lines
14 KiB
C

/*-
* Copyright (c) 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[] = "@(#)vs_line.c 10.19 (Berkeley) 9/26/96";
#endif /* not lint */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <bitstring.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include "../common/common.h"
#include "vi.h"
#ifdef VISIBLE_TAB_CHARS
#define TABCH '-'
#else
#define TABCH ' '
#endif
/*
* vs_line --
* Update one line on the screen.
*
* PUBLIC: int vs_line __P((SCR *, SMAP *, size_t *, size_t *));
*/
int
vs_line(sp, smp, yp, xp)
SCR *sp;
SMAP *smp;
size_t *xp, *yp;
{
CHAR_T *kp;
GS *gp;
SMAP *tsmp;
size_t chlen, cno_cnt, cols_per_screen, len, nlen;
size_t offset_in_char, offset_in_line, oldx, oldy;
size_t scno, skip_cols, skip_screens;
int ch, dne, is_cached, is_partial, is_tab;
int list_tab, list_dollar;
char *p, *cbp, *ecbp, cbuf[128];
#if defined(DEBUG) && 0
TRACE(sp, "vs_line: row %u: line: %u off: %u\n",
smp - HMAP, smp->lno, smp->off);
#endif
/*
* If ex modifies the screen after ex output is already on the screen,
* don't touch it -- we'll get scrolling wrong, at best.
*/
if (!F_ISSET(sp, SC_TINPUT_INFO) && VIP(sp)->totalcount > 1)
return (0);
if (F_ISSET(sp, SC_SCR_EXWROTE) && smp - HMAP != LASTLINE(sp))
return (0);
/*
* Assume that, if the cache entry for the line is filled in, the
* line is already on the screen, and all we need to do is return
* the cursor position. If the calling routine doesn't need the
* cursor position, we can just return.
*/
is_cached = SMAP_CACHE(smp);
if (yp == NULL && is_cached)
return (0);
/*
* A nasty side effect of this routine is that it returns the screen
* position for the "current" character. Not pretty, but this is the
* only routine that really knows what's out there.
*
* Move to the line. This routine can be called by vs_sm_position(),
* which uses it to fill in the cache entry so it can figure out what
* the real contents of the screen are. Because of this, we have to
* return to whereever we started from.
*/
gp = sp->gp;
(void)gp->scr_cursor(sp, &oldy, &oldx);
(void)gp->scr_move(sp, smp - HMAP, 0);
/* Get the line. */
dne = db_get(sp, smp->lno, 0, &p, &len);
/*
* Special case if we're printing the info/mode line. Skip printing
* the leading number, as well as other minor setup. The only time
* this code paints the mode line is when the user is entering text
* for a ":" command, so we can put the code here instead of dealing
* with the empty line logic below. This is a kludge, but it's pretty
* much confined to this module.
*
* Set the number of columns for this screen.
* Set the number of chars or screens to skip until a character is to
* be displayed.
*/
cols_per_screen = sp->cols;
if (O_ISSET(sp, O_LEFTRIGHT)) {
skip_screens = 0;
skip_cols = smp->coff;
} else {
skip_screens = smp->soff - 1;
skip_cols = skip_screens * cols_per_screen;
}
list_tab = O_ISSET(sp, O_LIST);
if (F_ISSET(sp, SC_TINPUT_INFO))
list_dollar = 0;
else {
list_dollar = list_tab;
/*
* If O_NUMBER is set, the line doesn't exist and it's line
* number 1, i.e., an empty file, display the line number.
*
* If O_NUMBER is set, the line exists and the first character
* on the screen is the first character in the line, display
* the line number.
*
* !!!
* If O_NUMBER set, decrement the number of columns in the
* first screen. DO NOT CHANGE THIS -- IT'S RIGHT! The
* rest of the code expects this to reflect the number of
* columns in the first screen, regardless of the number of
* columns we're going to skip.
*/
if (O_ISSET(sp, O_NUMBER)) {
cols_per_screen -= O_NUMBER_LENGTH;
if ((!dne || smp->lno == 1) && skip_cols == 0) {
nlen = snprintf(cbuf,
sizeof(cbuf), O_NUMBER_FMT, smp->lno);
(void)gp->scr_addstr(sp, cbuf, nlen);
}
}
}
/*
* Special case non-existent lines and the first line of an empty
* file. In both cases, the cursor position is 0, but corrected
* as necessary for the O_NUMBER field, if it was displayed.
*/
if (dne || len == 0) {
/* Fill in the cursor. */
if (yp != NULL && smp->lno == sp->lno) {
*yp = smp - HMAP;
*xp = sp->cols - cols_per_screen;
}
/* If the line is on the screen, quit. */
if (is_cached)
goto ret1;
/* Set line cache information. */
smp->c_sboff = smp->c_eboff = 0;
smp->c_scoff = smp->c_eclen = 0;
/*
* Lots of special cases for empty lines, but they only apply
* if we're displaying the first screen of the line.
*/
if (skip_cols == 0)
if (dne) {
if (smp->lno == 1) {
if (list_dollar) {
ch = '$';
goto empty;
}
} else {
ch = '~';
goto empty;
}
} else
if (list_dollar) {
ch = '$';
empty: (void)gp->scr_addstr(sp,
KEY_NAME(sp, ch), KEY_LEN(sp, ch));
}
(void)gp->scr_clrtoeol(sp);
(void)gp->scr_move(sp, oldy, oldx);
return (0);
}
/*
* If we just wrote this or a previous line, we cached the starting
* and ending positions of that line. The way it works is we keep
* information about the lines displayed in the SMAP. If we're
* painting the screen in the forward direction, this saves us from
* reformatting the physical line for every line on the screen. This
* wins big on binary files with 10K lines.
*
* Test for the first screen of the line, then the current screen line,
* then the line behind us, then do the hard work. Note, it doesn't
* do us any good to have a line in front of us -- it would be really
* hard to try and figure out tabs in the reverse direction, i.e. how
* many spaces a tab takes up in the reverse direction depends on
* what characters preceded it.
*
* Test for the first screen of the line.
*/
if (skip_cols == 0) {
smp->c_sboff = offset_in_line = 0;
smp->c_scoff = offset_in_char = 0;
p = &p[offset_in_line];
goto display;
}
/* Test to see if we've seen this exact line before. */
if (is_cached) {
offset_in_line = smp->c_sboff;
offset_in_char = smp->c_scoff;
p = &p[offset_in_line];
/* Set cols_per_screen to 2nd and later line length. */
if (O_ISSET(sp, O_LEFTRIGHT) || skip_cols > cols_per_screen)
cols_per_screen = sp->cols;
goto display;
}
/* Test to see if we saw an earlier part of this line before. */
if (smp != HMAP &&
SMAP_CACHE(tsmp = smp - 1) && tsmp->lno == smp->lno) {
if (tsmp->c_eclen != tsmp->c_ecsize) {
offset_in_line = tsmp->c_eboff;
offset_in_char = tsmp->c_eclen;
} else {
offset_in_line = tsmp->c_eboff + 1;
offset_in_char = 0;
}
/* Put starting info for this line in the cache. */
smp->c_sboff = offset_in_line;
smp->c_scoff = offset_in_char;
p = &p[offset_in_line];
/* Set cols_per_screen to 2nd and later line length. */
if (O_ISSET(sp, O_LEFTRIGHT) || skip_cols > cols_per_screen)
cols_per_screen = sp->cols;
goto display;
}
scno = 0;
offset_in_line = 0;
offset_in_char = 0;
/* Do it the hard way, for leftright scrolling screens. */
if (O_ISSET(sp, O_LEFTRIGHT)) {
for (; offset_in_line < len; ++offset_in_line) {
chlen = (ch = *(u_char *)p++) == '\t' && !list_tab ?
TAB_OFF(scno) : KEY_LEN(sp, ch);
if ((scno += chlen) >= skip_cols)
break;
}
/* Set cols_per_screen to 2nd and later line length. */
cols_per_screen = sp->cols;
/* Put starting info for this line in the cache. */
if (scno != skip_cols) {
smp->c_sboff = offset_in_line;
smp->c_scoff =
offset_in_char = chlen - (scno - skip_cols);
--p;
} else {
smp->c_sboff = ++offset_in_line;
smp->c_scoff = 0;
}
}
/* Do it the hard way, for historic line-folding screens. */
else {
for (; offset_in_line < len; ++offset_in_line) {
chlen = (ch = *(u_char *)p++) == '\t' && !list_tab ?
TAB_OFF(scno) : KEY_LEN(sp, ch);
if ((scno += chlen) < cols_per_screen)
continue;
scno -= cols_per_screen;
/* Set cols_per_screen to 2nd and later line length. */
cols_per_screen = sp->cols;
/*
* If crossed the last skipped screen boundary, start
* displaying the characters.
*/
if (--skip_screens == 0)
break;
}
/* Put starting info for this line in the cache. */
if (scno != 0) {
smp->c_sboff = offset_in_line;
smp->c_scoff = offset_in_char = chlen - scno;
--p;
} else {
smp->c_sboff = ++offset_in_line;
smp->c_scoff = 0;
}
}
display:
/*
* Set the number of characters to skip before reaching the cursor
* character. Offset by 1 and use 0 as a flag value. Vs_line is
* called repeatedly with a valid pointer to a cursor position.
* Don't fill anything in unless it's the right line and the right
* character, and the right part of the character...
*/
if (yp == NULL ||
smp->lno != sp->lno || sp->cno < offset_in_line ||
offset_in_line + cols_per_screen < sp->cno) {
cno_cnt = 0;
/* If the line is on the screen, quit. */
if (is_cached)
goto ret1;
} else
cno_cnt = (sp->cno - offset_in_line) + 1;
/* This is the loop that actually displays characters. */
ecbp = (cbp = cbuf) + sizeof(cbuf) - 1;
for (is_partial = 0, scno = 0;
offset_in_line < len; ++offset_in_line, offset_in_char = 0) {
if ((ch = *(u_char *)p++) == '\t' && !list_tab) {
scno += chlen = TAB_OFF(scno) - offset_in_char;
is_tab = 1;
} else {
scno += chlen = KEY_LEN(sp, ch) - offset_in_char;
is_tab = 0;
}
/*
* Only display up to the right-hand column. Set a flag if
* the entire character wasn't displayed for use in setting
* the cursor. If reached the end of the line, set the cache
* info for the screen. Don't worry about there not being
* characters to display on the next screen, its lno/off won't
* match up in that case.
*/
if (scno >= cols_per_screen) {
if (is_tab == 1) {
chlen -= scno - cols_per_screen;
smp->c_ecsize = smp->c_eclen = chlen;
scno = cols_per_screen;
} else {
smp->c_ecsize = chlen;
chlen -= scno - cols_per_screen;
smp->c_eclen = chlen;
if (scno > cols_per_screen)
is_partial = 1;
}
smp->c_eboff = offset_in_line;
/* Terminate the loop. */
offset_in_line = len;
}
/*
* If the caller wants the cursor value, and this was the
* cursor character, set the value. There are two ways to
* put the cursor on a character -- if it's normal display
* mode, it goes on the last column of the character. If
* it's input mode, it goes on the first. In normal mode,
* set the cursor only if the entire character was displayed.
*/
if (cno_cnt &&
--cno_cnt == 0 && (F_ISSET(sp, SC_TINPUT) || !is_partial)) {
*yp = smp - HMAP;
if (F_ISSET(sp, SC_TINPUT))
*xp = scno - chlen;
else
*xp = scno - 1;
if (O_ISSET(sp, O_NUMBER) &&
!F_ISSET(sp, SC_TINPUT_INFO) && skip_cols == 0)
*xp += O_NUMBER_LENGTH;
/* If the line is on the screen, quit. */
if (is_cached)
goto ret1;
}
/* If the line is on the screen, don't display anything. */
if (is_cached)
continue;
#define FLUSH { \
*cbp = '\0'; \
(void)gp->scr_addstr(sp, cbuf, cbp - cbuf); \
cbp = cbuf; \
}
/*
* Display the character. We do tab expansion here because
* the screen interface doesn't have any way to set the tab
* length. Note, it's theoretically possible for chlen to
* be larger than cbuf, if the user set a impossibly large
* tabstop.
*/
if (is_tab)
while (chlen--) {
if (cbp >= ecbp)
FLUSH;
*cbp++ = TABCH;
}
else {
if (cbp + chlen >= ecbp)
FLUSH;
for (kp = KEY_NAME(sp, ch) + offset_in_char; chlen--;)
*cbp++ = *kp++;
}
}
if (scno < cols_per_screen) {
/* If didn't paint the whole line, update the cache. */
smp->c_ecsize = smp->c_eclen = KEY_LEN(sp, ch);
smp->c_eboff = len - 1;
/*
* If not the info/mode line, and O_LIST set, and at the
* end of the line, and the line ended on this screen,
* add a trailing $.
*/
if (list_dollar) {
++scno;
chlen = KEY_LEN(sp, '$');
if (cbp + chlen >= ecbp)
FLUSH;
for (kp = KEY_NAME(sp, '$'); chlen--;)
*cbp++ = *kp++;
}
/* If still didn't paint the whole line, clear the rest. */
if (scno < cols_per_screen)
(void)gp->scr_clrtoeol(sp);
}
/* Flush any buffered characters. */
if (cbp > cbuf)
FLUSH;
ret1: (void)gp->scr_move(sp, oldy, oldx);
return (0);
}
/*
* vs_number --
* Repaint the numbers on all the lines.
*
* PUBLIC: int vs_number __P((SCR *));
*/
int
vs_number(sp)
SCR *sp;
{
GS *gp;
SMAP *smp;
VI_PRIVATE *vip;
size_t len, oldy, oldx;
int exist;
char nbuf[10];
gp = sp->gp;
vip = VIP(sp);
/* No reason to do anything if we're in input mode on the info line. */
if (F_ISSET(sp, SC_TINPUT_INFO))
return (0);
/*
* Try and avoid getting the last line in the file, by getting the
* line after the last line in the screen -- if it exists, we know
* we have to to number all the lines in the screen. Get the one
* after the last instead of the last, so that the info line doesn't
* fool us. (The problem is that file_lline will lie, and tell us
* that the info line is the last line in the file.) If that test
* fails, we have to check each line for existence.
*/
exist = db_exist(sp, TMAP->lno + 1);
(void)gp->scr_cursor(sp, &oldy, &oldx);
for (smp = HMAP; smp <= TMAP; ++smp) {
/* Numbers are only displayed for the first screen line. */
if (O_ISSET(sp, O_LEFTRIGHT)) {
if (smp->coff != 0)
continue;
} else
if (smp->soff != 1)
continue;
/*
* The first line of an empty file gets numbered, otherwise
* number any existing line.
*/
if (smp->lno != 1 && !exist && !db_exist(sp, smp->lno))
break;
(void)gp->scr_move(sp, smp - HMAP, 0);
len = snprintf(nbuf, sizeof(nbuf), O_NUMBER_FMT, smp->lno);
(void)gp->scr_addstr(sp, nbuf, len);
}
(void)gp->scr_move(sp, oldy, oldx);
return (0);
}