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/*
* (c) 2007, Quest Software, Inc. All rights reserved.
*
* This file is part of XScreenSaver,
* Copyright (c) 1993-2009 Jamie Zawinski <jwz@jwz.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*/
#include <stdlib.h>
#include <ctype.h>
#include <X11/Xlib.h>
#include "mlstring.h"
#define LINE_SPACING 1.2
static mlstring *
mlstring_allocate(const char *msg);
static void
mlstring_calculate(mlstring *str, XFontStruct *font);
mlstring*
mlstring_new(const char *msg, XFontStruct *font, Dimension wrap_width)
{
mlstring *newstr;
if (!(newstr = mlstring_allocate(msg)))
return NULL;
newstr->font_id = font->fid;
mlstring_wrap(newstr, font, wrap_width);
return newstr;
}
mlstring *
mlstring_allocate(const char *msg)
{
const char *s;
mlstring *ml;
struct mlstr_line *cur, *prev = NULL;
size_t linelength;
int the_end = 0;
if (!msg)
return NULL;
ml = calloc(1, sizeof(mlstring));
if (!ml)
return NULL;
for (s = msg; !the_end; msg = ++s)
{
/* New string struct */
cur = calloc(1, sizeof(struct mlstr_line));
if (!cur)
goto fail;
if (!ml->lines)
ml->lines = cur;
/* Find the \n or end of string */
while (*s != '\n')
{
if (*s == '\0')
{
the_end = 1;
break;
}
++s;
}
linelength = s - msg;
/* Duplicate the string */
cur->line = malloc(linelength + 1);
if (!cur->line)
goto fail;
strncpy(cur->line, msg, linelength);
cur->line[linelength] = '\0';
if (prev)
prev->next_line = cur;
prev = cur;
}
return ml;
fail:
if (ml)
mlstring_free(ml);
return NULL;
}
/*
* Frees an mlstring.
* This function does not have any unit tests.
*/
void
mlstring_free(mlstring *str) {
struct mlstr_line *cur, *next;
for (cur = str->lines; cur; cur = next) {
next = cur->next_line;
free(cur->line);
free(cur);
}
free(str);
}
void
mlstring_wrap(mlstring *mstring, XFontStruct *font, Dimension width)
{
short char_width = font->max_bounds.width;
int line_length, wrap_at;
struct mlstr_line *mstr, *newml;
/* An alternative implementation of this function would be to keep trying
* XTextWidth() on space-delimited substrings until the longest one less
* than 'width' is found, however there shouldn't be much difference
* between that, and this implementation.
*/
for (mstr = mstring->lines; mstr; mstr = mstr->next_line)
{
if (XTextWidth(font, mstr->line, strlen(mstr->line)) > width)
{
/* Wrap it */
line_length = width / char_width;
if (line_length == 0)
line_length = 1;
/* First try to soft wrap by finding a space */
for (wrap_at = line_length; wrap_at >= 0 && !isspace(mstr->line[wrap_at]); --wrap_at);
if (wrap_at == -1) /* No space found, hard wrap */
wrap_at = line_length;
else
wrap_at++; /* Leave the space at the end of the line. */
newml = calloc(1, sizeof(*newml));
if (!newml) /* OOM, don't bother trying to wrap */
break;
if (NULL == (newml->line = strdup(mstr->line + wrap_at)))
{
/* OOM, jump ship */
free(newml);
break;
}
/* Terminate the existing string at its end */
mstr->line[wrap_at] = '\0';
newml->next_line = mstr->next_line;
mstr->next_line = newml;
}
}
mlstring_calculate(mstring, font);
}
#undef MAX
#define MAX(x, y) ((x) > (y) ? (x) : (y))
/*
* Calculates the overall extents (width + height of the multi-line string).
* This function is called as part of mlstring_new().
* It does not have any unit testing.
*/
void
mlstring_calculate(mlstring *str, XFontStruct *font) {
struct mlstr_line *line;
str->font_height = font->ascent + font->descent;
str->overall_height = 0;
str->overall_width = 0;
/* XXX: Should there be some baseline calculations to help XDrawString later on? */
str->font_ascent = font->ascent;
for (line = str->lines; line; line = line->next_line)
{
line->line_width = XTextWidth(font, line->line, strlen(line->line));
str->overall_width = MAX(str->overall_width, line->line_width);
/* Don't add line spacing for the first line */
str->overall_height += (font->ascent + font->descent) *
(line == str->lines ? 1 : LINE_SPACING);
}
}
void
mlstring_draw(Display *dpy, Drawable dialog, GC gc, mlstring *string, int x, int y) {
struct mlstr_line *line;
if (!string)
return;
y += string->font_ascent;
XSetFont(dpy, gc, string->font_id);
for (line = string->lines; line; line = line->next_line)
{
XDrawString(dpy, dialog, gc, x, y, line->line, strlen(line->line));
y += string->font_height * LINE_SPACING;
}
}
/* vim:ts=8:sw=2:noet
*/
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