vt: fix background color on line feed

A command that causes a line feed while a background color is active, such as perl -e 'print "x" x 60, "\e[44m", "x" x 40, "\e[0m\n"' and perl -e 'print "x" x 40, "\e[44m\n", "x" x 40, "\e[0m\n"' causes the line that was started as a result of the line feed to be completely filled with the currently active background color instead of the default color. When scrolling, part of the current screen is memcpy'd/memmove'd to the new region, and the new line(s) that will appear as a result are cleared using memset. However, the lines are cleared with vc->vc_video_erase_char, causing them to be colored with the currently active background color. This is different from X11 terminal emulators which always paint the new lines with the default background color (e.g. `xterm -bg black`). The clear operation (\e[1J and \e[2J) also use vc_video_erase_char, so a new vc->vc_scrl_erase_char is introduced with contains the erase character used for scrolling, which is built from vc->vc_def_color instead of vc->vc_color.

Jan Engelhardt committed 18 years ago

Commit c9e587a1 parent 3265e666 files · +14 −12Browse files

Unified · Split

6 files

drivers/char/vt.c +4 −3
drivers/video/console/fbcon.c +4 −4
drivers/video/console/mdacon.c +1 −1
drivers/video/console/sticon.c +2 −2
drivers/video/console/vgacon.c +2 −2
include/linux/console_struct.h +1 −0

drivers/char/vt.c+4−3

@@ -301,7 +301,7 @@ static void scrup(struct vc_data *vc, unsigned int t, unsigned int b, int nr) · 300 unmodified lines
301	301	d = (unsigned short )(vc->vc_origin + vc->vc_size_row t);
302	302	s = (unsigned short )(vc->vc_origin + vc->vc_size_row (t + nr));
303	303	scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
304		− scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_video_erase_char,
	304	+ scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_scrl_erase_char,
305	305	vc->vc_size_row * nr);
306	306	}
307	307
@@ -319,7 +319,7 @@ static void scrdown(struct vc_data *vc, unsigned int t, unsigned int b, int nr) · 11 unmodified lines
319	319	s = (unsigned short )(vc->vc_origin + vc->vc_size_row t);
320	320	step = vc->vc_cols * nr;
321	321	scr_memmovew(s + step, s, (b - t - nr) * vc->vc_size_row);
322		− scr_memsetw(s, vc->vc_video_erase_char, 2 * step);
	322	+ scr_memsetw(s, vc->vc_scrl_erase_char, 2 * step);
323	323	}
324	324
325	325	static void do_update_region(struct vc_data *vc, unsigned long start, int count)
@@ -400,7 +400,7 @@ static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink, · 74 unmodified lines
400	400	* Bit 7 : blink
401	401	*/
402	402	{
403		− u8 a = vc->vc_color;
	403	+ u8 a = _color;
404	404	if (!vc->vc_can_do_color)
405	405	return _intensity \|
406	406	(_italic ? 2 : 0) \|
@@ -434,6 +434,7 @@ static void update_attr(struct vc_data *vc) · 27 unmodified lines
434	434	vc->vc_blink, vc->vc_underline,
435	435	vc->vc_reverse ^ vc->vc_decscnm, vc->vc_italic);
436	436	vc->vc_video_erase_char = (build_attr(vc, vc->vc_color, 1, vc->vc_blink, 0, vc->vc_decscnm, 0) << 8) \| ' ';
	437	+ vc->vc_scrl_erase_char = (build_attr(vc, vc->vc_def_color, 1, false, false, false, false) << 8) \| ' ';
437	438	}
438	439
439	440	/* Note: inverting the screen twice should revert to the original state */

drivers/video/console/fbcon.c+4−4

@@ -1881,7 +1881,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir, · 1880 unmodified lines
1881	1881	scr_memsetw((unsigned short *) (vc->vc_origin +
1882	1882	vc->vc_size_row *
1883	1883	(b - count)),
1884		− vc->vc_video_erase_char,
	1884	+ vc->vc_scrl_erase_char,
1885	1885	vc->vc_size_row * count);
1886	1886	return 1;
1887	1887	break;
@@ -1953,7 +1953,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir, · 65 unmodified lines
1953	1953	scr_memsetw((unsigned short *) (vc->vc_origin +
1954	1954	vc->vc_size_row *
1955	1955	(b - count)),
1956		− vc->vc_video_erase_char,
	1956	+ vc->vc_scrl_erase_char,
1957	1957	vc->vc_size_row * count);
1958	1958	return 1;
1959	1959	}
@@ -1972,7 +1972,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir, · 12 unmodified lines
1972	1972	scr_memsetw((unsigned short *) (vc->vc_origin +
1973	1973	vc->vc_size_row *
1974	1974	t),
1975		− vc->vc_video_erase_char,
	1975	+ vc->vc_scrl_erase_char,
1976	1976	vc->vc_size_row * count);
1977	1977	return 1;
1978	1978	break;
@@ -2042,7 +2042,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir, · 63 unmodified lines
2042	2042	scr_memsetw((unsigned short *) (vc->vc_origin +
2043	2043	vc->vc_size_row *
2044	2044	t),
2045		− vc->vc_video_erase_char,
	2045	+ vc->vc_scrl_erase_char,
2046	2046	vc->vc_size_row * count);
2047	2047	return 1;
2048	2048	}

drivers/video/console/mdacon.c+1−1

@@ -531,7 +531,7 @@ static void mdacon_cursor(struct vc_data *c, int mode) · 530 unmodified lines
531	531
532	532	static int mdacon_scroll(struct vc_data *c, int t, int b, int dir, int lines)
533	533	{
534		− u16 eattr = mda_convert_attr(c->vc_video_erase_char);
	534	+ u16 eattr = mda_convert_attr(c->vc_scrl_erase_char);
535	535
536	536	if (!lines)
537	537	return 0;

drivers/video/console/sticon.c+2−2

@@ -170,12 +170,12 @@ static int sticon_scroll(struct vc_data *conp, int t, int b, int dir, int count) · 169 unmodified lines
170	170	switch (dir) {
171	171	case SM_UP:
172	172	sti_bmove(sti, t + count, 0, t, 0, b - t - count, conp->vc_cols);
173		− sti_clear(sti, b - count, 0, count, conp->vc_cols, conp->vc_video_erase_char);
	173	+ sti_clear(sti, b - count, 0, count, conp->vc_cols, conp->vc_scrl_erase_char);
174	174	break;
175	175
176	176	case SM_DOWN:
177	177	sti_bmove(sti, t, 0, t + count, 0, b - t - count, conp->vc_cols);
178		− sti_clear(sti, t, 0, count, conp->vc_cols, conp->vc_video_erase_char);
	178	+ sti_clear(sti, t, 0, count, conp->vc_cols, conp->vc_scrl_erase_char);
179	179	break;
180	180	}
181	181

drivers/video/console/vgacon.c+2−2

@@ -1350,7 +1350,7 @@ static int vgacon_scroll(struct vc_data *c, int t, int b, int dir, · 1349 unmodified lines
1350	1350	} else
1351	1351	c->vc_origin += delta;
1352	1352	scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
1353		− delta), c->vc_video_erase_char,
	1353	+ delta), c->vc_scrl_erase_char,
1354	1354	delta);
1355	1355	} else {
1356	1356	if (oldo - delta < vga_vram_base) {
@@ -1363,7 +1363,7 @@ static int vgacon_scroll(struct vc_data *c, int t, int b, int dir, · 6 unmodified lines
1363	1363	} else
1364	1364	c->vc_origin -= delta;
1365	1365	c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
1366		− scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,
	1366	+ scr_memsetw((u16 *) (c->vc_origin), c->vc_scrl_erase_char,
1367	1367	delta);
1368	1368	}
1369	1369	c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;

include/linux/console_struct.h+1−0

@@ -53,6 +53,7 @@ struct vc_data { · 52 unmodified lines
53	53	unsigned short vc_hi_font_mask; /* [#] Attribute set for upper 256 chars of font or 0 if not supported */
54	54	struct console_font vc_font; /* Current VC font set */
55	55	unsigned short vc_video_erase_char; /* Background erase character */
	56	+ unsigned short vc_scrl_erase_char; /* Erase character for scroll */
56	57	/* VT terminal data */
57	58	unsigned int vc_state; /* Escape sequence parser state */
58	59	unsigned int vc_npar,vc_par[NPAR]; /* Parameters of current escape sequence */