minix/commands/yap/display.c
2009-11-09 10:26:00 +00:00

547 lines
11 KiB
C

/* Copyright (c) 1985 Ceriel J.H. Jacobs */
# ifndef lint
static char rcsid[] = "$Header$";
# endif
# define _DISPLAY_
# include "in_all.h"
# include "display.h"
# include "assert.h"
# include "machine.h"
# include "term.h"
# include "output.h"
# include "options.h"
# include "process.h"
# include "getline.h"
# include "main.h"
STATIC char * do_line();
/*
* Fill n lines of the screen, each with "str".
*/
STATIC VOID
fillscr(n,str) char *str; int n; {
while (n-- > 0) {
putline(str);
}
}
/*
* Skip "n" screenlines of line "p", and return what's left of it.
*/
STATIC char *
skiplines(p,n) char *p; int n; {
while (n-- > 0) {
p = do_line(p,0);
scr_info.currentpos--;
}
return p;
}
/*
* Redraw screen.
* "n" = 1 if it is a real redraw, 0 if one page must be displayed.
* It is also called when yap receives a stop signal.
*/
VOID
redraw(n) int n; {
register struct scr_info *p = &scr_info;
register int i;
i = pagesize;
if (n && p->currentpos) {
i = p->currentpos;
}
(VOID) display(p->firstline,p->nf,i,1);
}
/*
* Compute return value for the routines "display" and "scrollf".
* This return value indicates wether we are at the end of file
* or at the start, or both.
* "s" contains that part of the last line that was not displayed.
*/
STATIC int
compretval(s) char *s; {
register int i;
register struct scr_info *p = &scr_info;
i = 0;
if (!s || (!*s && !getline(p->lastline+1, 1))) {
i = EOFILE;
}
if (p->firstline == 1 && !p->nf) {
i |= START;
}
status = i;
return i;
}
/*
* Display nlines, starting at line n, not displaying the first
* nd screenlines of n.
* If reallydispl = 0, the actual displaying is not performed,
* only the computing associated with it is done.
*/
int
display(n,nd,nlines,reallydispl)
long n; int nd; register int nlines; int reallydispl; {
register struct scr_info *s = &scr_info;
register char *p; /* pointer to line to be displayed */
if (startcomm) { /* No displaying on a command from the
* yap command line. In this case, displaying
* will be done after executing the command,
* by a redraw.
*/
reallydispl = 0;
}
if (!n) {
n = 1L;
nd = 0;
}
if (reallydispl) { /* move cursor to starting point */
if (stupid) {
putline(currentfile);
putline(", line ");
prnum(n);
nlines--;
}
if (cflag) {
putline("\r\n");
}
else {
home();
clrscreen();
}
}
/*
* Now, do computations and display
*/
s->currentpos = 0;
s->nf = nd;
s->head = s->tail;
s->tail->cnt = 0;
s->tail->line = n;
p = skiplines(getline(n,1),nd);
while (nlines && p) {
/*
* While there is room,
* and there is something left to display ...
*/
(s->tail->cnt)++;
nlines--;
if (*(p = do_line(p,reallydispl)) == '\0') {
/*
* File-line finished, get next one ...
*/
p = getline(++n,1);
if (nlines && p) {
s->tail = s->tail->next;
s->tail->cnt = 0;
s->tail->line = n;
}
}
}
if (!stupid) {
s->currentpos += nlines;
if (reallydispl) {
fillscr(nlines, "~\r\n");
fillscr(maxpagesize - s->currentpos, "\r\n");
}
}
return compretval(p);
}
/*
* Scroll forwards n lines.
*/
int
scrollf(n,reallydispl) int n; int reallydispl; {
register struct scr_info *s = &scr_info;
register char *p;
register long ll;
register int i;
/*
* First, find out how many screenlines of the last line were already
* on the screen, and possibly above it.
*/
if (n <= 0 || (status & EOFILE)) return status;
if (startcomm) reallydispl = 0;
/*
* Find out where to begin displaying
*/
i = s->tail->cnt;
if ((ll = s->lastline) == s->firstline) i += s->nf;
p = skiplines(getline(ll, 1), i);
/*
* Now, place the cursor at the first free line
*/
if (reallydispl && !stupid) {
clrbline();
mgoto(s->currentpos);
}
/*
* Now display lines, keeping track of which lines are on the screen.
*/
while (n-- > 0) { /* There are still rows to be displayed */
if (!*p) { /* End of line, get next one */
if (!(p = getline(++ll, 1))) {
/*
* No lines left. At end of file
*/
break;
}
s->tail = s->tail->next;
s->tail->cnt = 0;
s->tail->line = ll;
}
if (s->currentpos >= maxpagesize) {
/*
* No room, delete first screen-line
*/
s->currentpos--;
s->nf++;
if (--(s->head->cnt) == 0) {
/*
* The first file-line on the screen is wiped
* out completely; update administration
* accordingly.
*/
s->nf = 0;
s->head = s->head->next;
assert(s->head->cnt > 0);
}
}
s->tail->cnt++;
p = do_line(p, reallydispl);
}
return compretval(p);
}
/*
* Scroll back n lines
*/
int
scrollb(n, reallydispl) int n, reallydispl; {
register struct scr_info *s = &scr_info;
register char *p; /* Holds string to be displayed */
register int i;
register int count;
register long ln; /* a line number */
register int nodispl;
int cannotscroll; /* stupid or no insert-line */
/*
* First, find out where to start
*/
if ((count = n) <= 0 || (status & START)) return status;
if (startcomm) reallydispl = 0;
cannotscroll = stupid || (!*AL && !*SR);
ln = s->firstline;
nodispl = s->nf;
while (count) { /* While scrolling back ... */
if (i = nodispl) {
/*
* There were screen-lines of s->firstline that were not
* displayed.
* We can use them now, but only "count" of them.
*/
if (i > count) i = count;
s->currentpos += i;
nodispl -= i;
count -= i;
}
else { /* Get previous line */
if (ln == 1) break; /* isn't there ... */
p = getline(--ln, 1);
/*
* Make it the first line of the screen and compute
* how many screenlines it takes. These lines are not
* displayed, but nodispl is set to this count, so
* that it will be nonzero next time around
*/
nodispl = 0;
do { /* Find out how many screenlines */
nodispl++;
p = skiplines(p, 1);
} while (*p);
}
}
n -= count;
if ((i = s->currentpos) > maxpagesize) i = maxpagesize;
if (reallydispl && hardcopy) i = n;
/*
* Now that we know where to start, we can use "display" to do the
* rest of the computing for us, and maybe even the displaying ...
*/
i = display(ln,
nodispl,
i,
reallydispl && cannotscroll);
if (cannotscroll || !reallydispl) {
/*
* Yes, "display" did the displaying, or we did'nt have to
* display at all.
* I like it, but the user obviously does not.
* Let him buy another (smarter) terminal ...
*/
return i;
}
/*
* Now, all we have to do is the displaying. And we are dealing with
* a smart terminal (it can insert lines or scroll back).
*/
home();
/*
* Insert lines all at once
*/
for (i = n; i; i--) {
if (DB && *CE) {
/*
* Grumble..., terminal retains lines below, so we have
* to clear the lines that we push off the screen
*/
clrbline();
home();
}
if (*SR) {
scrollreverse();
}
else {
# ifdef VT100_PATCH
insert_line(0);
# else
insert_line();
# endif
}
}
p = skiplines(getline(ln = s->firstline, 1), s->nf);
for (i = 0; i < n; i++) {
p = do_line(p,1);
s->currentpos--;
if (!*p) {
p = getline(++ln, 1);
}
}
return count;
}
/*
* Process a line.
* If reallydispl > 0 then display it.
*/
STATIC char *
do_line(str, reallydispl) register char *str; int reallydispl; {
char buf[1024];
register char *p = buf;
register int pos = COLS;
register int c;
register int c1;
register int do_ul = 0, do_hl = 0;
int lastmode = 0, lasthlmode = 0;
int c2;
while (*str && pos > 0) {
if (*str < ' ' && (c1 = match(str,&c2,sppat)) > 0) {
/*
* We found a string that matches, and thus must be
* echoed literally
*/
if ((pos - c2) <= 0) {
/*
* It did not fit
*/
break;
}
pos -= c2;
str += c1;
if (reallydispl) {
c = *str;
*p = *str = 0;
cputline(p = buf);
putline(str - c1);
*str = c;
}
continue;
}
c = *str++;
do_hl = 0;
if (*str == '\b' && *(str+1) != 0
&& (c != '_' || *(str+2) == '\b')) {
while (*str == '\b' && *(str+1) != 0) {
str++;
c = *str++;
do_hl = 1;
}
}
do_ul = 1;
/*
* Find underline sequences ...
*/
if (c == '_' && *str == '\b') {
str++;
c = *str++;
}
else {
if (*str == '\b' && *(str+1) == '_') {
str += 2;
}
else do_ul = 0;
}
if (reallydispl && do_hl != lasthlmode) {
*p = 0;
cputline(p = buf);
if (do_hl) bold();
else end_bold();
}
lasthlmode = do_hl;
if (reallydispl && do_ul != lastmode) {
*p = 0;
cputline(p = buf);
if (do_ul) underline();
else end_underline();
}
lastmode = do_ul;
*p++ = c;
if (c >= ' ' && c < 0177) {
pos--;
if (reallydispl && do_ul && *UC && pos > 0) {
/*
* Underlining apparently is done one
* character at a time.
*/
*p = 0;
cputline(p = buf);
backspace();
underchar();
}
continue;
}
if (c == '\t') {
p--;
c1 = 8 - ((COLS - pos) & 07);
/*
* Actually, if COLS is a multiple of 8, this can be
* simplified to
* c1 = pos & 07;
* But of course, we don't know that for sure.
*/
if (pos - c1 < 0) break;
pos -= c1;
if (reallydispl) {
if (expandtabs) {
/*
* Expand tabs. We cannot let the
* kernel take care of this
* for two reasons:
* 1. There can be tabs in cursor
* addressing strings,
* 2. We probably do it better.
*/
while (c1-- > 0) {
*p++ = ' ';
}
}
else {
*p = 0;
cputline(p = buf);
givetab();
}
}
continue;
}
/*
* Now we have a control character, which takes two positions
*/
if (pos <= 1) {
p--;
break;
}
pos -= 2;
}
if (reallydispl) {
*p = 0;
cputline(buf);
if (pos > 0 || (pos <= 0 && (!AM || XN))) {
putline("\r\n");
}
/*
* The next should be here! I.e. it may not be before printing
* the newline. This has to do with XN. We don't know exactly
* WHEN the terminal will stop ignoring the newline.
* I have for example a terminal (Ampex a230) that will
* continue to ignore the newline after a clear to end of line
* sequence, but not after an end_underline sequence.
*/
if (do_ul) {
end_underline();
}
if (do_hl) {
standend();
}
}
scr_info.currentpos++;
return str;
}
/* ARGSUSED */
int
setmark(cnt) long cnt; { /* Set a mark on the current page */
register struct scr_info *p = &scr_info;
p->savfirst = p->firstline;
p->savnf = p->nf;
}
/* ARGSUSED */
int
tomark(cnt) long cnt; { /* Go to the mark */
register struct scr_info *p = &scr_info;
(VOID) display(p->savfirst,p->savnf,pagesize,1);
}
/* ARGSUSED */
int
exgmark(cnt) long cnt; { /* Exchange mark and current page */
register struct scr_info *p = &scr_info;
register long svfirst;
register int svnf;
svfirst = p->firstline;
svnf = p->nf;
tomark(0L);
p->savfirst = svfirst;
p->savnf = svnf;
}
VOID
d_clean() { /* Clean up */
register struct scr_info *p = &scr_info;
p->savnf = 0;
p->savfirst = 0;
p->head = p->tail;
p->head->line = 0;
p->currentpos = 0;
}