tables.c

一个很有名的浏览器

		 * whole cell width. */
		expand_lines(table->part, x + width - 1, y, height, cell->bgcolor);

		if (cell->fragment_id)
			add_fragment_identifier(part, cell->fragment_id);
	}

	done_html_parser_state(state);

	if (part) mem_free(part);
}

static void
draw_table_cells(struct table *table, int x, int y)
{
	int col, row;
	int xp;
	color_t bgcolor = par_format.bgcolor;
	struct table_frames table_frames;

	get_table_frames(table, &table_frames);

	if (table->fragment_id)
		add_fragment_identifier(table->part, table->fragment_id);

	/* Expand using the background color of the ``parent context'' all the
	 * way down the start of the left edge of the table. */
	expand_lines(table->part, x - 1, y, table->real_height, bgcolor);

	xp = x + table_frames.left;
	for (col = 0; col < table->cols; col++) {
		int yp = y + table_frames.top;

		for (row = 0; row < table->rows; row++) {
			int row_height = table->rows_heights[row] +
				(row < table->rows - 1 && has_hline_width(table, row + 1));

			draw_table_cell(table, col, row, xp, yp);

			yp += row_height;
		}

		if (col < table->cols - 1) {
			xp += table->cols_widths[col] + has_vline_width(table, col + 1);
		}
	}

	/* Finish the table drawing by aligning the right and bottom edge of
	 * the table */
	x += table->real_width - 1;
	expand_lines(table->part, x, y, table->real_height, table->bgcolor);

	/* Tables are renderer column-wise which breaks forms where the
	 * form items appears in a column before the actual form tag is
	 * parsed. Consider the folloing example:
	 *
	 *	+--------+--------+	Where cell 2 has a <form>-tag
	 *	| cell 1 | cell 2 |	and cell 3 has an <input>-tag.
	 *	+--------+--------+
	 *	| cell 3 | cell 4 |	The table is rendered by drawing
	 *	+--------+--------+	the cells in the order: 1, 3, 2, 4.
	 *
	 * That is the <input>-tag form-item is added before the <form>-tag,
	 * which means a ``dummy'' form to hold it is added too.
	 * Calling check_html_form_hierarchy() will join the the form-item
	 * to the correct form from cell 2. */
	check_html_form_hierarchy(table->part);

	/* Do a sanity check whether the height is correct */
	check_table_height(table, &table_frames, y);
}


static inline int
get_frame_pos(int a, int a_size, int b, int b_size)
{
	assert(a >= -1 || a < a_size + 2 || b >= 0 || b <= b_size);
	if_assert_failed return 0;
	return a + 1 + (a_size + 2) * b;
}

#define H_FRAME_POSITION(table, col, row) frame[0][get_frame_pos(col, (table)->cols, row, (table)->rows)]
#define V_FRAME_POSITION(table, col, row) frame[1][get_frame_pos(row, (table)->rows, col, (table)->cols)]

static inline void
draw_frame_point(struct table *table, signed char *frame[2], int x, int y,
		 int col, int row)
{
	/* TODO: Use /BORDER._.* / macros ! --pasky */
	static unsigned char const border_chars[81] = {
		0x00, 0xb3, 0xba,	0xc4, 0xc0, 0xd3,	0xcd, 0xd4, 0xc8,
		0xc4, 0xd9, 0xbd,	0xc4, 0xc1, 0xd0,	0xcd, 0xd4, 0xc8,
		0xcd, 0xbe, 0xbc,	0xcd, 0xbe, 0xbc,	0xcd, 0xcf, 0xca,

		0xb3, 0xb3, 0xba,	0xda, 0xc3, 0xd3,	0xd5, 0xc6, 0xc8,
		0xbf, 0xb4, 0xbd,	0xc2, 0xc5, 0xd0,	0xd5, 0xc6, 0xc8,
		0xb8, 0xb5, 0xbc,	0xb8, 0xb5, 0xbc,	0xd1, 0xd8, 0xca,

		0xba, 0xba, 0xba,	0xd6, 0xd6, 0xc7,	0xc9, 0xc9, 0xcc,
		0xb7, 0xb7, 0xb6,	0xd2, 0xd2, 0xd7,	0xc9, 0xc9, 0xcc,
		0xbb, 0xbb, 0xb9,	0xbb, 0xbb, 0xb9,	0xcb, 0xcb, 0xce,
	};
	/* Note: I have no clue wether any of these names are suitable but they
	 * should give an idea of what is going on. --jonas */
	signed char left   = H_FRAME_POSITION(table, col - 1,     row);
	signed char right  = H_FRAME_POSITION(table,     col,     row);
	signed char top    = V_FRAME_POSITION(table,     col, row - 1);
	signed char bottom = V_FRAME_POSITION(table,     col,     row);
	int pos;

	if (left < 0 && right < 0 && top < 0 && bottom < 0) return;

	pos =      int_max(top,    0)
	    +  3 * int_max(right,  0)
	    +  9 * int_max(left,   0)
	    + 27 * int_max(bottom, 0);

	draw_frame_hchars(table->part, x, y, 1, border_chars[pos],
			  par_format.bgcolor, table->bordercolor);
}

static inline void
draw_frame_hline(struct table *table, signed char *frame[2], int x, int y,
		 int col, int row)
{
	static unsigned char const hltable[] = { ' ', BORDER_SHLINE, BORDER_DHLINE };
	int pos = H_FRAME_POSITION(table, col, row);

	assertm(pos < 3, "Horizontal table position out of bound [%d]", pos);
	if_assert_failed return;

	if (pos < 0 || table->cols_widths[col] <= 0) return;

	draw_frame_hchars(table->part, x, y, table->cols_widths[col], hltable[pos],
			  par_format.bgcolor, table->bordercolor);
}

static inline void
draw_frame_vline(struct table *table, signed char *frame[2], int x, int y,
		 int col, int row)
{
	static unsigned char const vltable[] = { ' ', BORDER_SVLINE, BORDER_DVLINE };
	int pos = V_FRAME_POSITION(table, col, row);

	assertm(pos < 3, "Vertical table position out of bound [%d]", pos);
	if_assert_failed return;

	if (pos < 0 || table->rows_heights[row] <= 0) return;

	draw_frame_vchars(table->part, x, y, table->rows_heights[row], vltable[pos],
			  par_format.bgcolor, table->bordercolor);
}

static inline int
table_row_has_group(struct table *table, int row)
{
	int col;

	for (col = 0; col < table->cols; col++)
		if (CELL(table, col, row)->is_group)
			return 1;

	return 0;
}

static void
init_table_rules(struct table *table, signed char *frame[2])
{
	int col, row;

	for (row = 0; row < table->rows; row++) for (col = 0; col < table->cols; col++) {
		int xsp, ysp;
		struct table_cell *cell = CELL(table, col, row);

		if (!cell->is_used || cell->is_spanned) continue;

		xsp = cell->colspan ? cell->colspan : table->cols - col;
		ysp = cell->rowspan ? cell->rowspan : table->rows - row;

		if (table->rules != TABLE_RULE_COLS) {
			memset(&H_FRAME_POSITION(table, col, row), table->cellspacing, xsp);
			memset(&H_FRAME_POSITION(table, col, row + ysp), table->cellspacing, xsp);
		}

		if (table->rules != TABLE_RULE_ROWS) {
			memset(&V_FRAME_POSITION(table, col, row), table->cellspacing, ysp);
			memset(&V_FRAME_POSITION(table, col + xsp, row), table->cellspacing, ysp);
		}
	}

	if (table->rules == TABLE_RULE_GROUPS) {
		for (col = 1; col < table->cols; col++) {
			if (table->cols_x[col])
				continue;

			memset(&V_FRAME_POSITION(table, col, 0), 0, table->rows);
		}

		for (row = 1; row < table->rows; row++) {
			if (table_row_has_group(table, row))
				continue;

			memset(&H_FRAME_POSITION(table, 0, row), 0, table->cols);
		}
	}
}

static void
draw_table_frames(struct table *table, int indent, int y)
{
	struct table_frames table_frames;
	signed char *frame[2];
	int col, row;
	int cx, cy;
	int fh_size = (table->cols + 2) * (table->rows + 1);
	int fv_size = (table->cols + 1) * (table->rows + 2);

	frame[0] = fmem_alloc(fh_size + fv_size);
	if (!frame[0]) return;
	memset(frame[0], -1, fh_size + fv_size);

	frame[1] = &frame[0][fh_size];

	if (table->rules != TABLE_RULE_NONE)
		init_table_rules(table, frame);

	get_table_frames(table, &table_frames);
	memset(&H_FRAME_POSITION(table, 0, 0), table_frames.top, table->cols);
	memset(&H_FRAME_POSITION(table, 0, table->rows), table_frames.bottom, table->cols);
	memset(&V_FRAME_POSITION(table, 0, 0), table_frames.left, table->rows);
	memset(&V_FRAME_POSITION(table, table->cols, 0), table_frames.right, table->rows);

	cy = y;
	for (row = 0; row <= table->rows; row++) {
		cx = indent;
		if ((row > 0 && row < table->rows && has_hline_width(table, row))
		    || (row == 0 && table_frames.top)
		    || (row == table->rows && table_frames.bottom)) {
			int w = table_frames.left ? table->border : -1;

			for (col = 0; col < table->cols; col++) {
				if (col > 0)
					w = get_vline_width(table, col);

				if (w >= 0) {
					draw_frame_point(table, frame, cx, cy, col, row);
					if (row < table->rows)
						draw_frame_vline(table, frame, cx, cy + 1, col, row);
					cx++;
				}

				draw_frame_hline(table, frame, cx, cy, col, row);
				cx += table->cols_widths[col];
			}

			if (table_frames.right) {
				draw_frame_point(table, frame, cx, cy, col, row);
				if (row < table->rows)
					draw_frame_vline(table, frame, cx, cy + 1, col, row);
				cx++;
			}

			cy++;

		} else if (row < table->rows) {
			for (col = 0; col <= table->cols; col++) {
				if ((col > 0 && col < table->cols && has_vline_width(table, col))
				    || (col == 0 && table_frames.left)
				    || (col == table->cols && table_frames.right)) {
					draw_frame_vline(table, frame, cx, cy, col, row);
					cx++;
				}
				if (col < table->cols) cx += table->cols_widths[col];
			}
		}

		if (row < table->rows) cy += table->rows_heights[row];
	}

	fmem_free(frame[0]);
}

static void
draw_table_caption(struct table *table, int x, int y)
{
	unsigned char *start = table->caption.start;
	unsigned char *end = table->caption.end;
	struct part *part;

	if (!start || !end) return;

	while (start < end && isspace(*start))
		start++;

	while (start < end && isspace(end[-1]))
		end--;

	if (start >= end) return;

	part = format_html_part(start, end, table->align,
		0, table->real_width, table->part->document, x, y,
		NULL, table->link_num);

	if (part) {
		table->part->cy += part->box.height;
		table->part->cx = -1;
		table->part->link_num = part->link_num;
		mem_free(part);
	}
}

/* This renders tag soup elements that the parser detected while chewing it's
 * way through the table HTML. */
static void
draw_table_bad_html(struct table *table)
{
	int i;

	for (i = 0; i < table->bad_html_size; i++) {
		struct html_start_end *html = &table->bad_html[i];
		unsigned char *start = html->start;
		unsigned char *end = html->end;

		while (start < end && isspace(*start))
			start++;

		while (start < end && isspace(end[-1]))
			end--;

		if (start >= end) continue;

		parse_html(start, end, table->part, NULL);
	}
}

void
format_table(unsigned char *attr, unsigned char *html, unsigned char *eof,
	     unsigned char **end, struct part *part)
{
	struct table *table;
	struct node *node, *new_node;
	struct html_element *state;
	int indent, margins;

	html_context.table_level++;

	table = parse_table(html, eof, end, attr, (part->document || part->box.x));
	if (!table) goto ret0;

	table->part = part;

	/* XXX: This tag soup handling needs to be done outside the create
	 * parser state. Something to do with link numbering. */
	/* It needs to be done _before_ processing the actual table, too.
	 * Otherwise i.e. <form> tags between <table> and <tr> are broken. */
	draw_table_bad_html(table);

	state = init_html_parser_state(ELEMENT_DONT_KILL, ALIGN_LEFT, 0, 0);

	margins = par_format.leftmargin + par_format.rightmargin;
	if (get_table_cellpadding(table)) goto ret2;

	/* DBG("%d %d %d", t->min_width, t->max_width, table->width); */
	if (table->min_width >= table->width)
		distribute_widths(table, table->min_width);
	else if (table->max_width < table->width && table->full_width)
		distribute_widths(table, table->max_width);
	else
		distribute_widths(table, table->width);

	if (!part->document && part->box.x == 1) {
		int total_width = table->real_width + margins;

		int_bounds(&total_width, table->real_width, par_format.width);
		int_lower_bound(&part->box.width, total_width);
		part->cy += table->real_height;

		goto ret2;
	}

#ifdef HTML_TABLE_2ND_PASS
	check_table_widths(table);
#endif

	get_table_heights(table);

	if (!part->document) {
		int_lower_bound(&part->box.width, table->real_width + margins);
		part->cy += table->real_height;
		goto ret2;
	}

	node = part->document->nodes.next;
	node->box.height = part->box.y - node->box.y + part->cy;

	indent = get_table_indent(table);

	/* FIXME: See bug 432. It should be possible to align the caption at
	 * the top, bottom or the sides. */
	draw_table_caption(table, indent + part->box.x, part->box.y + part->cy);
	draw_table_cells(table, indent, part->cy);
	draw_table_frames(table, indent, part->cy);

	part->cy += table->real_height;
	part->cx = -1;

	new_node = mem_alloc(sizeof(*new_node));
	if (new_node) {
		set_box(&new_node->box, node->box.x, part->box.y + part->cy,
			node->box.width, 0);
		add_to_list(part->document->nodes, new_node);
	}

ret2:
	part->link_num = table->link_num;
	int_lower_bound(&part->box.height, part->cy);
	html_context.part = part; /* Might've changed in draw_table_cells(). */
	done_html_parser_state(state);

	free_table(table);

ret0:
	html_context.table_level--;
	if (!html_context.table_level) free_table_cache();
}