d8b5c7ed06
This has big improvements to the .info file utility support and much recent OSS requires its features.
558 lines
18 KiB
C
558 lines
18 KiB
C
/* display.c -- How to display Info windows.
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$Id: display.c,v 1.6 1997/07/24 21:13:27 karl Exp $
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Copyright (C) 1993, 97 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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Written by Brian Fox (bfox@ai.mit.edu). */
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#include "info.h"
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#include "display.h"
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extern int info_any_buffered_input_p (); /* Found in session.c. */
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static void free_display ();
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static DISPLAY_LINE **make_display ();
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/* An array of display lines which tell us what is currently visible on
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the display. */
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DISPLAY_LINE **the_display = (DISPLAY_LINE **)NULL;
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/* Non-zero means do no output. */
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int display_inhibited = 0;
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/* Initialize THE_DISPLAY to WIDTH and HEIGHT, with nothing in it. */
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void
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display_initialize_display (width, height)
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int width, height;
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{
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free_display (the_display);
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the_display = make_display (width, height);
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display_clear_display (the_display);
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}
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/* Clear all of the lines in DISPLAY making the screen blank. */
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void
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display_clear_display (display)
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DISPLAY_LINE **display;
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{
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register int i;
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register DISPLAY_LINE *display_line;
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for (i = 0; (display_line = display[i]); i++)
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{
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display[i]->text[0] = '\0';
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display[i]->textlen = 0;
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display[i]->inverse = 0;
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}
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}
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/* Non-zero if we didn't completely redisplay a window. */
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int display_was_interrupted_p = 0;
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/* Update the windows pointed to by WINDOW in the_display. This actually
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writes the text on the screen. */
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void
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display_update_display (window)
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WINDOW *window;
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{
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register WINDOW *win;
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display_was_interrupted_p = 0;
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/* For every window in the list, check contents against the display. */
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for (win = window; win; win = win->next)
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{
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/* Only re-display visible windows which need updating. */
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if (((win->flags & W_WindowVisible) == 0) ||
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((win->flags & W_UpdateWindow) == 0) ||
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(win->height == 0))
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continue;
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display_update_one_window (win);
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if (display_was_interrupted_p)
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break;
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}
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/* Always update the echo area. */
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display_update_one_window (the_echo_area);
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}
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/* Display WIN on the_display. Unlike display_update_display (), this
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function only does one window. */
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void
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display_update_one_window (win)
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WINDOW *win;
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{
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register char *nodetext; /* Current character to display. */
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register char *last_node_char; /* Position of the last character in node. */
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register int i; /* General use index. */
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char *printed_line; /* Buffer for a printed line. */
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int pl_index = 0; /* Index into PRINTED_LINE. */
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int line_index = 0; /* Number of lines done so far. */
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DISPLAY_LINE **display = the_display;
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/* If display is inhibited, that counts as an interrupted display. */
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if (display_inhibited)
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display_was_interrupted_p = 1;
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/* If the window has no height, or display is inhibited, quit now. */
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if (!win->height || display_inhibited)
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return;
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/* If the window's first row doesn't appear in the_screen, then it
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cannot be displayed. This can happen when the_echo_area is the
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window to be displayed, and the screen has shrunk to less than one
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line. */
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if ((win->first_row < 0) || (win->first_row > the_screen->height))
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return;
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/* Print each line in the window into our local buffer, and then
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check the contents of that buffer against the display. If they
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differ, update the display. */
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printed_line = (char *)xmalloc (1 + win->width);
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if (!win->node || !win->line_starts)
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goto done_with_node_display;
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nodetext = win->line_starts[win->pagetop];
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last_node_char = win->node->contents + win->node->nodelen;
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for (; nodetext < last_node_char; nodetext++)
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{
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char *rep, *rep_carried_over, rep_temp[2];
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int replen;
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if (isprint (*nodetext))
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{
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rep_temp[0] = *nodetext;
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replen = 1;
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rep_temp[1] = '\0';
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rep = rep_temp;
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}
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else
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{
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if (*nodetext == '\r' || *nodetext == '\n')
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{
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replen = win->width - pl_index;
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}
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else
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{
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rep = printed_representation (*nodetext, pl_index);
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replen = strlen (rep);
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}
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}
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/* If this character can be printed without passing the width of
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the line, then stuff it into the line. */
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if (replen + pl_index < win->width)
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{
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/* Optimize if possible. */
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if (replen == 1)
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{
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printed_line[pl_index++] = *rep;
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}
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else
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{
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for (i = 0; i < replen; i++)
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printed_line[pl_index++] = rep[i];
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}
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}
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else
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{
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DISPLAY_LINE *entry;
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/* If this character cannot be printed in this line, we have
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found the end of this line as it would appear on the screen.
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Carefully print the end of the line, and then compare. */
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if (*nodetext == '\n' || *nodetext == '\r' || *nodetext == '\t')
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{
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printed_line[pl_index] = '\0';
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rep_carried_over = (char *)NULL;
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}
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else
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{
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/* The printed representation of this character extends into
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the next line. Remember the offset of the last character
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printed out of REP so that we can carry the character over
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to the next line. */
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for (i = 0; pl_index < (win->width - 1);)
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printed_line[pl_index++] = rep[i++];
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rep_carried_over = rep + i;
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/* If printing the last character in this window couldn't
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possibly cause the screen to scroll, place a backslash
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in the rightmost column. */
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if (1 + line_index + win->first_row < the_screen->height)
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{
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if (win->flags & W_NoWrap)
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printed_line[pl_index++] = '$';
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else
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printed_line[pl_index++] = '\\';
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}
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printed_line[pl_index] = '\0';
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}
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/* We have the exact line as it should appear on the screen.
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Check to see if this line matches the one already appearing
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on the screen. */
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entry = display[line_index + win->first_row];
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/* If the screen line is inversed, then we have to clear
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the line from the screen first. Why, I don't know. */
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if (entry->inverse)
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{
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terminal_goto_xy (0, line_index + win->first_row);
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terminal_clear_to_eol ();
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entry->inverse = 0;
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entry->text[0] = '\0';
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entry->textlen = 0;
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}
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/* Find the offset where these lines differ. */
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for (i = 0; i < pl_index; i++)
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if (printed_line[i] != entry->text[i])
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break;
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/* If the lines are not the same length, or if they differed
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at all, we must do some redrawing. */
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if ((i != pl_index) || (pl_index != entry->textlen))
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{
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/* Move to the proper point on the terminal. */
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terminal_goto_xy (i, line_index + win->first_row);
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/* If there is any text to print, print it. */
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if (i != pl_index)
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terminal_put_text (printed_line + i);
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/* If the printed text didn't extend all the way to the edge
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of the window, and text was appearing between here and the
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edge of the window, clear from here to the end of the line. */
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if ((pl_index < win->width && pl_index < entry->textlen) ||
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(entry->inverse))
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terminal_clear_to_eol ();
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fflush (stdout);
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/* Update the display text buffer. */
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strcpy (entry->text + i, printed_line + i);
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entry->textlen = pl_index;
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/* Lines showing node text are not in inverse. Only modelines
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have that distinction. */
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entry->inverse = 0;
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}
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/* We have done at least one line. Increment our screen line
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index, and check against the bottom of the window. */
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if (++line_index == win->height)
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break;
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/* A line has been displayed, and the screen reflects that state.
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If there is typeahead pending, then let that typeahead be read
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now, instead of continuing with the display. */
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if (info_any_buffered_input_p ())
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{
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free (printed_line);
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display_was_interrupted_p = 1;
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return;
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}
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/* Reset PL_INDEX to the start of the line. */
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pl_index = 0;
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/* If there are characters from REP left to print, stuff them
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into the buffer now. */
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if (rep_carried_over)
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for (; rep[pl_index]; pl_index++)
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printed_line[pl_index] = rep[pl_index];
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/* If this window has chosen not to wrap lines, skip to the end
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of the physical line in the buffer, and start a new line here. */
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if (pl_index && (win->flags & W_NoWrap))
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{
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char *begin;
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pl_index = 0;
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printed_line[0] = '\0';
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begin = nodetext;
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while ((nodetext < last_node_char) && (*nodetext != '\n'))
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nodetext++;
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}
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}
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}
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done_with_node_display:
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/* We have reached the end of the node or the end of the window. If it
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is the end of the node, then clear the lines of the window from here
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to the end of the window. */
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for (; line_index < win->height; line_index++)
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{
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DISPLAY_LINE *entry = display[line_index + win->first_row];
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/* If this line has text on it then make it go away. */
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if (entry && entry->textlen)
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{
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entry->textlen = 0;
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entry->text[0] = '\0';
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terminal_goto_xy (0, line_index + win->first_row);
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terminal_clear_to_eol ();
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}
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}
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/* Finally, if this window has a modeline it might need to be redisplayed.
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Check the window's modeline against the one in the display, and update
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if necessary. */
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if ((win->flags & W_InhibitMode) == 0)
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{
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window_make_modeline (win);
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line_index = win->first_row + win->height;
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/* This display line must both be in inverse, and have the same
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contents. */
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if ((!display[line_index]->inverse) ||
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(strcmp (display[line_index]->text, win->modeline) != 0))
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{
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terminal_goto_xy (0, line_index);
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terminal_begin_inverse ();
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terminal_put_text (win->modeline);
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terminal_end_inverse ();
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strcpy (display[line_index]->text, win->modeline);
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display[line_index]->inverse = 1;
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display[line_index]->textlen = strlen (win->modeline);
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fflush (stdout);
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}
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}
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/* Okay, this window doesn't need updating anymore. */
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win->flags &= ~W_UpdateWindow;
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free (printed_line);
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fflush (stdout);
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}
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/* Scroll the region of the_display starting at START, ending at END, and
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moving the lines AMOUNT lines. If AMOUNT is less than zero, the lines
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are moved up in the screen, otherwise down. Actually, it is possible
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for no scrolling to take place in the case that the terminal doesn't
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support it. This doesn't matter to us. */
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void
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display_scroll_display (start, end, amount)
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int start, end, amount;
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{
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register int i, last;
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DISPLAY_LINE *temp;
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/* If this terminal cannot do scrolling, give up now. */
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if (!terminal_can_scroll)
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return;
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/* If there isn't anything displayed on the screen because it is too
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small, quit now. */
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if (!the_display[0])
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return;
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/* If there is typeahead pending, then don't actually do any scrolling. */
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if (info_any_buffered_input_p ())
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return;
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/* Do it on the screen. */
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terminal_scroll_terminal (start, end, amount);
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/* Now do it in the display buffer so our contents match the screen. */
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if (amount > 0)
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{
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last = end + amount;
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/* Shift the lines to scroll right into place. */
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for (i = 0; i < (end - start); i++)
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{
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temp = the_display[last - i];
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the_display[last - i] = the_display[end - i];
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the_display[end - i] = temp;
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}
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/* The lines have been shifted down in the buffer. Clear all of the
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lines that were vacated. */
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for (i = start; i != (start + amount); i++)
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{
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the_display[i]->text[0] = '\0';
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the_display[i]->textlen = 0;
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the_display[i]->inverse = 0;
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}
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}
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if (amount < 0)
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{
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last = start + amount;
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for (i = 0; i < (end - start); i++)
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{
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temp = the_display[last + i];
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the_display[last + i] = the_display[start + i];
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the_display[start + i] = temp;
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}
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/* The lines have been shifted up in the buffer. Clear all of the
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lines that are left over. */
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for (i = end + amount; i != end; i++)
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{
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the_display[i]->text[0] = '\0';
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the_display[i]->textlen = 0;
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the_display[i]->inverse = 0;
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}
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}
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}
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/* Try to scroll lines in WINDOW. OLD_PAGETOP is the pagetop of WINDOW before
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having had its line starts recalculated. OLD_STARTS is the list of line
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starts that used to appear in this window. OLD_COUNT is the number of lines
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that appear in the OLD_STARTS array. */
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void
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display_scroll_line_starts (window, old_pagetop, old_starts, old_count)
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WINDOW *window;
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int old_pagetop, old_count;
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char **old_starts;
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{
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register int i, old, new; /* Indices into the line starts arrays. */
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int last_new, last_old; /* Index of the last visible line. */
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int old_first, new_first; /* Index of the first changed line. */
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int unchanged_at_top = 0;
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int already_scrolled = 0;
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/* Locate the first line which was displayed on the old window. */
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old_first = old_pagetop;
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new_first = window->pagetop;
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/* Find the last line currently visible in this window. */
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last_new = window->pagetop + (window->height - 1);
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if (last_new > window->line_count)
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last_new = window->line_count - 1;
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/* Find the last line which used to be currently visible in this window. */
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last_old = old_pagetop + (window->height - 1);
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if (last_old > old_count)
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last_old = old_count - 1;
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for (old = old_first, new = new_first;
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old < last_old && new < last_new;
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old++, new++)
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if (old_starts[old] != window->line_starts[new])
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break;
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else
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unchanged_at_top++;
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/* Loop through the old lines looking for a match in the new lines. */
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for (old = old_first + unchanged_at_top; old < last_old; old++)
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{
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for (new = new_first; new < last_new; new++)
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if (old_starts[old] == window->line_starts[new])
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{
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/* Find the extent of the matching lines. */
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for (i = 0; (old + i) < last_old; i++)
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if (old_starts[old + i] != window->line_starts[new + i])
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break;
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/* Scroll these lines if there are enough of them. */
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{
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int start, end, amount;
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start = (window->first_row
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+ ((old + already_scrolled) - old_pagetop));
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amount = new - (old + already_scrolled);
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end = window->first_row + window->height;
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/* If we are shifting the block of lines down, then the last
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AMOUNT lines will become invisible. Thus, don't bother
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scrolling them. */
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if (amount > 0)
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end -= amount;
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if ((end - start) > 0)
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{
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display_scroll_display (start, end, amount);
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/* Some lines have been scrolled. Simulate the scrolling
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by offsetting the value of the old index. */
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old += i;
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already_scrolled += amount;
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}
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}
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}
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}
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}
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/* Move the screen cursor to directly over the current character in WINDOW. */
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void
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display_cursor_at_point (window)
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WINDOW *window;
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{
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int vpos, hpos;
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vpos = window_line_of_point (window) - window->pagetop + window->first_row;
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hpos = window_get_cursor_column (window);
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terminal_goto_xy (hpos, vpos);
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fflush (stdout);
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}
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/* **************************************************************** */
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/* */
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/* Functions Static to this File */
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/* */
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/* **************************************************************** */
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/* Make a DISPLAY_LINE ** with width and height. */
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static DISPLAY_LINE **
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make_display (width, height)
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int width, height;
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{
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register int i;
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DISPLAY_LINE **display;
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display = (DISPLAY_LINE **)xmalloc ((1 + height) * sizeof (DISPLAY_LINE *));
|
||
|
||
for (i = 0; i < height; i++)
|
||
{
|
||
display[i] = (DISPLAY_LINE *)xmalloc (sizeof (DISPLAY_LINE));
|
||
display[i]->text = (char *)xmalloc (1 + width);
|
||
display[i]->textlen = 0;
|
||
display[i]->inverse = 0;
|
||
}
|
||
display[i] = (DISPLAY_LINE *)NULL;
|
||
return (display);
|
||
}
|
||
|
||
/* Free the storage allocated to DISPLAY. */
|
||
static void
|
||
free_display (display)
|
||
DISPLAY_LINE **display;
|
||
{
|
||
register int i;
|
||
register DISPLAY_LINE *display_line;
|
||
|
||
if (!display)
|
||
return;
|
||
|
||
for (i = 0; (display_line = display[i]); i++)
|
||
{
|
||
free (display_line->text);
|
||
free (display_line);
|
||
}
|
||
free (display);
|
||
}
|