gcc/texinfo/info/footnotes.c

262 lines
7.7 KiB
C

/* footnotes.c -- Some functions for manipulating footnotes.
$Id: footnotes.c,v 1.1.1.2 1998/03/22 20:42:29 law Exp $
Copyright (C) 1993, 97 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Written by Brian Fox (bfox@ai.mit.edu). */
#include "info.h"
/* Non-zero means attempt to show footnotes when displaying a new window. */
int auto_footnotes_p = 1;
static char *footnote_nodename = "*Footnotes*";
#define FOOTNOTE_HEADER_FORMAT \
"*** Footnotes appearing in the node \"%s\" ***\n"
/* Find the window currently showing footnotes. */
static WINDOW *
find_footnotes_window ()
{
WINDOW *win;
/* Try to find an existing window first. */
for (win = windows; win; win = win->next)
if (internal_info_node_p (win->node) &&
(strcmp (win->node->nodename, footnote_nodename) == 0))
break;
return (win);
}
/* Manufacture a node containing the footnotes of this node, and
return the manufactured node. If NODE has no footnotes, return a
NULL pointer. */
NODE *
make_footnotes_node (node)
NODE *node;
{
NODE *fn_node, *result = (NODE *)NULL;
long fn_start;
/* Make the initial assumption that the footnotes appear as simple
text within this windows node. */
fn_node = node;
/* See if this node contains the magic footnote label. */
fn_start =
info_search_in_node (FOOTNOTE_LABEL, node, 0, (WINDOW *)NULL, 1);
/* If it doesn't, check to see if it has an associated footnotes node. */
if (fn_start == -1)
{
REFERENCE **refs;
refs = info_xrefs_of_node (node);
if (refs)
{
register int i;
char *refname;
refname = (char *)xmalloc
(1 + strlen ("-Footnotes") + strlen (node->nodename));
strcpy (refname, node->nodename);
strcat (refname, "-Footnotes");
for (i = 0; refs[i]; i++)
if ((refs[i]->nodename != (char *)NULL) &&
(strcmp (refs[i]->nodename, refname) == 0))
{
char *filename;
filename = node->parent;
if (!filename)
filename = node->filename;
fn_node = info_get_node (filename, refname);
if (fn_node)
fn_start = 0;
break;
}
free (refname);
info_free_references (refs);
}
}
/* If we never found the start of a footnotes area, quit now. */
if (fn_start == -1)
return ((NODE *)NULL);
/* Make the new node. */
result = (NODE *)xmalloc (sizeof (NODE));
result->flags = 0;
/* Get the size of the footnotes appearing within this node. */
{
char *header;
long text_start = fn_start;
header = (char *)xmalloc
(1 + strlen (node->nodename) + strlen (FOOTNOTE_HEADER_FORMAT));
sprintf (header, FOOTNOTE_HEADER_FORMAT, node->nodename);
/* Move the start of the displayed text to right after the first line.
This effectively skips either "---- footno...", or "File: foo...". */
while (text_start < fn_node->nodelen)
if (fn_node->contents[text_start++] == '\n')
break;
result->nodelen = strlen (header) + fn_node->nodelen - text_start;
/* Set the contents of this node. */
result->contents = (char *)xmalloc (1 + result->nodelen);
sprintf (result->contents, "%s", header);
memcpy (result->contents + strlen (header),
fn_node->contents + text_start, fn_node->nodelen - text_start);
name_internal_node (result, footnote_nodename);
free (header);
}
#if defined (NOTDEF)
/* If the footnotes were gleaned from the node that we were called with,
shorten the calling node's display length. */
if (fn_node == node)
narrow_node (node, 0, fn_start);
#endif /* NOTDEF */
return (result);
}
/* Create or delete the footnotes window depending on whether footnotes
exist in WINDOW's node or not. Returns FN_FOUND if footnotes were found
and displayed. Returns FN_UNFOUND if there were no footnotes found
in WINDOW's node. Returns FN_UNABLE if there were footnotes, but the
window to show them couldn't be made. */
int
info_get_or_remove_footnotes (window)
WINDOW *window;
{
WINDOW *fn_win;
NODE *new_footnotes;
fn_win = find_footnotes_window ();
/* If we are in the footnotes window, change nothing. */
if (fn_win == window)
return (FN_FOUND);
/* Try to find footnotes for this window's node. */
new_footnotes = make_footnotes_node (window->node);
/* If there was a window showing footnotes, and there are no footnotes
for the current window, delete the old footnote window. */
if (fn_win && !new_footnotes)
{
if (windows->next)
info_delete_window_internal (fn_win);
}
/* If there are footnotes for this window's node, but no window around
showing footnotes, try to make a new window. */
if (new_footnotes && !fn_win)
{
WINDOW *old_active;
WINDOW *last, *win;
/* Always make this window be the last one appearing in the list. Find
the last window in the chain. */
for (win = windows, last = windows; win; last = win, win = win->next);
/* Try to split this window, and make the split window the one to
contain the footnotes. */
old_active = active_window;
active_window = last;
fn_win = window_make_window (new_footnotes);
active_window = old_active;
if (!fn_win)
{
free (new_footnotes->contents);
free (new_footnotes);
/* If we are hacking automatic footnotes, and there are footnotes
but we couldn't display them, print a message to that effect. */
if (auto_footnotes_p)
inform_in_echo_area (_("Footnotes could not be displayed"));
return (FN_UNABLE);
}
}
/* If there are footnotes, and there is a window to display them,
make that window be the number of lines appearing in the footnotes. */
if (new_footnotes && fn_win)
{
window_set_node_of_window (fn_win, new_footnotes);
window_change_window_height
(fn_win, fn_win->line_count - fn_win->height);
remember_window_and_node (fn_win, new_footnotes);
add_gcable_pointer (new_footnotes->contents);
}
if (!new_footnotes)
return (FN_UNFOUND);
else
return (FN_FOUND);
}
/* Show the footnotes associated with this node in another window. */
DECLARE_INFO_COMMAND (info_show_footnotes,
_("Show the footnotes associated with this node in another window"))
{
/* A negative argument means just make the window go away. */
if (count < 0)
{
WINDOW *fn_win = find_footnotes_window ();
/* If there is an old footnotes window, and it isn't the only window
on the screen, delete it. */
if (fn_win && windows->next)
info_delete_window_internal (fn_win);
}
else
{
int result;
result = info_get_or_remove_footnotes (window);
switch (result)
{
case FN_UNFOUND:
info_error (NO_FOOT_NODE);
break;
case FN_UNABLE:
info_error (WIN_TOO_SMALL);
break;
}
}
}