renderer.c

来自「elinks下lynx是最重要的二个文本浏览器, 在linux下非常实用, el」· C语言 代码 · 共 2,052 行 · 第 1/4 页

			} else {
				int to_move = link->npoints - (i + 1);

				assert(to_move >= 0);

				if (to_move > 0) {
					memmove(&link->points[i],
						&link->points[i + 1],
						to_move *
						sizeof(*link->points));
					i--;
				}

				link->npoints--;
			}
		}

		if (!matched) {
			renderer_context.last_link_to_move = nlink;
		}
	}

	/* Don't move tags when removing links. */
	if (yt < 0) return;

	matched = 0;
	tag = renderer_context.last_tag_to_move;

	while (list_has_next(part->document->tags, tag)) {
		tag = tag->next;

		if (tag->y == Y(yf)) {
			matched = 1;
			if (tag->x >= X(xf)) {
				tag->y = Y(yt);
				tag->x += -xf + xt;
			}

		} else if (!matched && tag->y > Y(yf)) {
			/* Fix for bug 479 (part two) */
			matched = 1;
		}

		if (!matched) renderer_context.last_tag_to_move = tag;
	}
}

static inline void
copy_chars(struct html_context *html_context, int x, int y, int width, struct screen_char *d)
{
	struct part *part;

	assert(html_context);
	if_assert_failed return;

	part = html_context->part;

	assert(width > 0 && part && part->document && part->document->data);
	if_assert_failed return;

	if (realloc_line(html_context, part->document, Y(y), X(x) + width - 1))
		return;

	copy_screen_chars(&POS(x, y), d, width);
}

static inline void
move_chars(struct html_context *html_context, int x, int y, int nx, int ny)
{
	struct part *part;

	assert(html_context);
	if_assert_failed return;

	part = html_context->part;

	assert(part && part->document && part->document->data);
	if_assert_failed return;

	if (LEN(y) - x <= 0) return;
	copy_chars(html_context, nx, ny, LEN(y) - x, &POS(x, y));

	LINE(y).length = X(x);
	move_links(html_context, x, y, nx, ny);
}

static inline void
shift_chars(struct html_context *html_context, int y, int shift)
{
	struct part *part;
	struct screen_char *a;
	int len;

	assert(html_context);
	if_assert_failed return;

	part = html_context->part;

	assert(part && part->document && part->document->data);
	if_assert_failed return;

	len = LEN(y);

	a = fmem_alloc(len * sizeof(*a));
	if (!a) return;

	copy_screen_chars(a, &POS(0, y), len);

	clear_hchars(html_context, 0, y, shift);
	copy_chars(html_context, shift, y, len, a);
	fmem_free(a);

	move_links(html_context, 0, y, shift, y);
}

static inline void
del_chars(struct html_context *html_context, int x, int y)
{
	struct part *part;

	assert(html_context);
	if_assert_failed return;

	part = html_context->part;

	assert(part && part->document && part->document->data);
	if_assert_failed return;

	LINE(y).length = X(x);
	move_links(html_context, x, y, -1, -1);
}

#define overlap(x) int_max((x).width - (x).rightmargin, 0)

static int inline
split_line_at(struct html_context *html_context, int width)
{
	struct part *part;
	int tmp;
	int new_width = width + par_format.rightmargin;

	assert(html_context);
	if_assert_failed return 0;

	part = html_context->part;

	assert(part);
	if_assert_failed return 0;

	/* Make sure that we count the right margin to the total
	 * actual box width. */
	int_lower_bound(&part->box.width, new_width);

	if (part->document) {
		assert(part->document->data);
		if_assert_failed return 0;
		assertm(POS(width, part->cy).data == ' ',
			"bad split: %c", POS(width, part->cy).data);
		move_chars(html_context, width + 1, part->cy, par_format.leftmargin, part->cy + 1);
		del_chars(html_context, width, part->cy);
	}

	width++; /* Since we were using (x + 1) only later... */

	tmp = part->spaces_len - width;
	if (tmp > 0) {
		/* 0 is possible and I'm paranoid ... --Zas */
		memmove(part->spaces, part->spaces + width, tmp);
	}

	assert(tmp >= 0);
	if_assert_failed tmp = 0;
	memset(part->spaces + tmp, 0, width);

	if (par_format.leftmargin > 0) {
		tmp = part->spaces_len - par_format.leftmargin;
		assertm(tmp > 0, "part->spaces_len - par_format.leftmargin == %d", tmp);
		/* So tmp is zero, memmove() should survive that. Don't recover. */
		memmove(part->spaces + par_format.leftmargin, part->spaces, tmp);
	}

	part->cy++;

	if (part->cx == width) {
		part->cx = -1;
		int_lower_bound(&part->box.height, part->cy);
		return 2;
	} else {
		part->cx -= width - par_format.leftmargin;
		int_lower_bound(&part->box.height, part->cy + 1);
		return 1;
	}
}

/* Here, we scan the line for a possible place where we could split it into two
 * (breaking it, because it is too long), if it is overlapping from the maximal
 * box width. */
/* Returns 0 if there was found no spot suitable for breaking the line.
 *         1 if the line was split into two.
 *         2 if the (second) splitted line is blank (that is useful to determine
 *           ie. if the next line_break() should really break the line; we don't
 *           want to see any blank lines to pop up, do we?). */
static int
split_line(struct html_context *html_context)
{
	struct part *part;
	int x;

	assert(html_context);
	if_assert_failed return 0;

	part = html_context->part;

	assert(part);
	if_assert_failed return 0;

	for (x = overlap(par_format); x >= par_format.leftmargin; x--)
		if (x < part->spaces_len && part->spaces[x])
			return split_line_at(html_context, x);

	for (x = par_format.leftmargin; x < part->cx ; x++)
		if (x < part->spaces_len && part->spaces[x])
			return split_line_at(html_context, x);

	/* Make sure that we count the right margin to the total
	 * actual box width. */
	int_lower_bound(&part->box.width, part->cx + par_format.rightmargin);

	return 0;
}

/* Insert @new_spaces spaces before the coordinates @x and @y,
 * adding those spaces to whatever link is at those coordinates. */
/* TODO: Integrate with move_links. */
static void
insert_spaces_in_link(struct part *part, int x, int y, int new_spaces)
{
	int i = part->document->nlinks;

	x = X(x);
	y = Y(y);

	while (i--) {
		struct link *link = &part->document->links[i];
		int j = link->npoints;

		while (j-- > 1) {
			struct point *point = &link->points[j];

			if (point->x != x || point->y != y)
				continue;

			if (!realloc_points(link, link->npoints + new_spaces))
				return;

			link->npoints += new_spaces;
			point = &link->points[link->npoints - 1];

			while (new_spaces--) {
				point->x = --x;
				point->y = y;
				point--;
			}

			return;
		}
	}
}

/* This function is very rare exemplary of clean and beautyful code here.
 * Please handle with care. --pasky */
static void
justify_line(struct html_context *html_context, int y)
{
	struct part *part;
	struct screen_char *line; /* we save original line here */
	int len;
	int pos;
	int *space_list;
	int spaces;
	int diff;

	assert(html_context);
	if_assert_failed return;

	part = html_context->part;

	assert(part && part->document && part->document->data);
	if_assert_failed return;

	len = LEN(y);
	assert(len > 0);
	if_assert_failed return;

	line = fmem_alloc(len * sizeof(*line));
	if (!line) return;

	/* It may sometimes happen that the line is only one char long and that
	 * char is space - then we're going to write to both [0] and [1], but
	 * we allocated only one field. Thus, we've to do (len + 1). --pasky */
	space_list = fmem_alloc((len + 1) * sizeof(*space_list));
	if (!space_list) {
		fmem_free(line);
		return;
	}

	copy_screen_chars(line, &POS(0, y), len);

	/* Skip leading spaces */

	spaces = 0;
	pos = 0;

	while (line[pos].data == ' ')
		pos++;

	/* Yes, this can be negative, we know. But we add one to it always
	 * anyway, so it's ok. */
	space_list[spaces++] = pos - 1;

	/* Count spaces */

	for (; pos < len; pos++)
		if (line[pos].data == ' ')
			space_list[spaces++] = pos;

	space_list[spaces] = len;

	/* Realign line */

	/* Diff is the difference between the width of the paragraph
	 * and the current length of the line. */
	diff = overlap(par_format) - len;

	/* We check diff > 0 because diff can be negative (i.e., we have
	 * an unbroken line of length > overlap(par_format))
	 * even when spaces > 1 if the line has only non-breaking spaces. */
	if (spaces > 1 && diff > 0) {
		int prev_end = 0;
		int word;

		clear_hchars(html_context, 0, y, overlap(par_format));

		for (word = 0; word < spaces; word++) {
			/* We have to increase line length by 'diff' num. of
			 * characters, so we move 'word'th word 'word_shift'
			 * characters right. */
			int word_start = space_list[word] + 1;
			int word_len = space_list[word + 1] - word_start;
			int word_shift;
			int new_start;
			int new_spaces;

			assert(word_len >= 0);
			if_assert_failed continue;
			if (!word_len) continue;

			word_shift = (word * diff) / (spaces - 1);
			new_start = word_start + word_shift;

			copy_chars(html_context, new_start, y, word_len,
				   &line[word_start]);

			new_spaces = new_start - prev_end - 1;
			if (word && new_spaces) {
				move_links(html_context, prev_end + 1, y, new_start, y);
				insert_spaces_in_link(part,
						      new_start, y, new_spaces);
			}

			prev_end = new_start + word_len;
		}
	}

	fmem_free(space_list);
	fmem_free(line);
}

static void
align_line(struct html_context *html_context, int y, int last)
{
	struct part *part;
	int shift;
	int len;

	assert(html_context);
	if_assert_failed return;

	part = html_context->part;

	assert(part && part->document && part->document->data);
	if_assert_failed return;

	len = LEN(y);

	if (!len || par_format.align == ALIGN_LEFT)
		return;

	if (par_format.align == ALIGN_JUSTIFY) {
		if (!last)
			justify_line(html_context, y);
		return;
	}

	shift = overlap(par_format) - len;
	if (par_format.align == ALIGN_CENTER)
		shift /= 2;
	if (shift > 0)
		shift_chars(html_context, y, shift);
}

static inline void
init_link_event_hooks(struct html_context *html_context, struct link *link)
{
	link->event_hooks = mem_calloc(1, sizeof(*link->event_hooks));
	if (!link->event_hooks) return;

#define add_evhook(list_, type_, src_)						\
	do {									\
		struct script_event_hook *evhook;				\
										\
		if (!src_) break;						\
										\
		evhook = mem_calloc(1, sizeof(*evhook));			\
		if (!evhook) break;						\
										\
		evhook->type = type_;						\
		evhook->src  = stracpy(src_);					\
		add_to_list(*(list_), evhook);					\
	} while (0)

	init_list(*link->event_hooks);
	add_evhook(link->event_hooks, SEVHOOK_ONCLICK, format.onclick);
	add_evhook(link->event_hooks, SEVHOOK_ONDBLCLICK, format.ondblclick);
	add_evhook(link->event_hooks, SEVHOOK_ONMOUSEOVER, format.onmouseover);
	add_evhook(link->event_hooks, SEVHOOK_ONHOVER, format.onhover);
	add_evhook(link->event_hooks, SEVHOOK_ONFOCUS, format.onfocus);
	add_evhook(link->event_hooks, SEVHOOK_ONMOUSEOUT, format.onmouseout);
	add_evhook(link->event_hooks, SEVHOOK_ONBLUR, format.onblur);

#undef add_evhook
}

static struct link *
new_link(struct html_context *html_context, unsigned char *name, int namelen)
{
	struct document *document;
	struct part *part;
	int link_number;
	struct link *link;

	assert(html_context);
	if_assert_failed return NULL;

	part = html_context->part;

	assert(part);
	if_assert_failed return NULL;

	document = part->document;

	assert(document);
	if_assert_failed return NULL;

	link_number = part->link_num;

	if (!ALIGN_LINK(&document->links, document->nlinks, document->nlinks + 1))
		return NULL;

	link = &document->links[document->nlinks++];
	link->number = link_number - 1;
	if (document->options.use_tabindex) link->number += format.tabindex;
	link->accesskey = format.accesskey;
	link->title = null_or_stracpy(format.title);
	link->where_img = null_or_stracpy(format.image);

	if (!format.form) {
		link->target = null_or_stracpy(format.target);
		link->data.name = memacpy(name, namelen);
		/* if (strlen(url) > 4 && !strncasecmp(url, "MAP@", 4)) { */
		if (format.link
		    && ((format.link[0]|32) == 'm')
		    && ((format.link[1]|32) == 'a')
		    && ((format.link[2]|32) == 'p')
		    && 	(format.link[3]     == '@')
		    &&   format.link[4]) {
			link->type = LINK_MAP;
			link->where = stracpy(format.link + 4);
		} else {
			link->type = LINK_HYPERTEXT;
			link->where = null_or_stracpy(format.link);
		}

	} else {
		struct form_control *fc = format.form;
		struct form *form;

		switch (fc->type) {
		case FC_TEXT:
		case FC_PASSWORD:
		case FC_FILE:
			link->type = LINK_FIELD;
			break;
		case FC_TEXTAREA:
			link->type = LINK_AREA;
			break;
		case FC_CHECKBOX:
		case FC_RADIO:
			link->type = LINK_CHECKBOX;
			break;
		case FC_SELECT:
			link->type = LINK_SELECT;
			break;