Fix VGA screen dump (4c5e8c5c) · Commits · SUMMER2020 / students / proj-2021291

hw/vga.c

+86 −27

Original line number	Diff line number	Diff line
		@@ -1223,6 +1223,35 @@ static const uint8_t cursor_glyph[32 * 4] = {
		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
		};

		static void vga_get_text_resolution(VGAState s, int pwidth, int *pheight,
		int pcwidth, int pcheight)
		{
		int width, cwidth, height, cheight;

		/* total width & height */
		cheight = (s->cr[9] & 0x1f) + 1;
		cwidth = 8;
		if (!(s->sr[1] & 0x01))
		cwidth = 9;
		if (s->sr[1] & 0x08)
		cwidth = 16; /* NOTE: no 18 pixel wide */
		width = (s->cr[0x01] + 1);
		if (s->cr[0x06] == 100) {
		/* ugly hack for CGA 160x100x16 - explain me the logic */
		height = 100;
		} else {
		height = s->cr[0x12] \|
		((s->cr[0x07] & 0x02) << 7) \|
		((s->cr[0x07] & 0x40) << 3);
		height = (height + 1) / cheight;
		}

		*pwidth = width;
		*pheight = height;
		*pcwidth = cwidth;
		*pcheight = cheight;
		}

		/*
		* Text mode update
		* Missing:
		@@ -1275,24 +1304,8 @@ static void vga_draw_text(VGAState *s, int full_update)
		line_offset = s->line_offset;
		s1 = s->vram_ptr + (s->start_addr * 4);

		/* total width & height */
		cheight = (s->cr[9] & 0x1f) + 1;
		cw = 8;
		if (!(s->sr[1] & 0x01))
		cw = 9;
		if (s->sr[1] & 0x08)
		cw = 16; /* NOTE: no 18 pixel wide */
		vga_get_text_resolution(s, &width, &height, &cw, &cheight);
		x_incr = cw * ((ds_get_bits_per_pixel(s->ds) + 7) >> 3);
		width = (s->cr[0x01] + 1);
		if (s->cr[0x06] == 100) {
		/* ugly hack for CGA 160x100x16 - explain me the logic */
		height = 100;
		} else {
		height = s->cr[0x12] \|
		((s->cr[0x07] & 0x02) << 7) \|
		((s->cr[0x07] & 0x40) << 3);
		height = (height + 1) / cheight;
		}
		if ((height * width) > CH_ATTR_SIZE) {
		/* better than nothing: exit if transient size is too big */
		return;
		@@ -2542,11 +2555,29 @@ int ppm_save(const char filename, uint8_t data,
		return 0;
		}

		/* save the vga display in a PPM image even if no display is
		available */
		static void vga_screen_dump(void opaque, const char filename)
		static void vga_screen_dump_blank(VGAState s, const char filename)
		{
		FILE *f;
		unsigned int y, x, w, h;

		w = s->last_scr_width * sizeof(uint32_t);
		h = s->last_scr_height;

		f = fopen(filename, "wb");
		if (!f)
		return;
		fprintf(f, "P6\n%d %d\n%d\n", w, h, 255);
		for (y = 0; y < h; y++) {
		for (x = 0; x < w; x++) {
		fputc(0, f);
		}
		}
		fclose(f);
		}

		static void vga_screen_dump_common(VGAState s, const char filename,
		int w, int h)
		{
		VGAState s = (VGAState )opaque;
		DisplayState saved_ds, ds1, ds = &ds1;

		/* XXX: this is a little hackish */
		@@ -2559,14 +2590,42 @@ static void vga_screen_dump(void opaque, const char filename)
		ds->dpy_refresh = vga_save_dpy_refresh;
		ds->depth = 32;

		ds->linesize = w * sizeof(uint32_t);
		ds->data = qemu_mallocz(h * ds->linesize);
		s->ds = ds;
		s->graphic_mode = -1;
		vga_update_display(s);
		ppm_save(filename, ds->data, w, h, ds->linesize);
		qemu_free(ds->data);
		s->ds = saved_ds;
		}

		static void vga_screen_dump_graphic(VGAState s, const char filename)
		{
		int w, h;

		if (ds_get_data(ds)) {
		ppm_save(filename, ds_get_data(ds), vga_save_w, vga_save_h,
		ds_get_linesize(s->ds));
		qemu_free(ds_get_data(ds));
		s->get_resolution(s, &w, &h);
		vga_screen_dump_common(s, filename, w, h);
		}
		s->ds = saved_ds;

		static void vga_screen_dump_text(VGAState s, const char filename)
		{
		int w, h, cwidth, cheight;

		vga_get_text_resolution(s, &w, &h, &cwidth, &cheight);
		vga_screen_dump_common(s, filename, w * cwidth, h * cheight);
		}

		/* save the vga display in a PPM image even if no display is
		available */
		static void vga_screen_dump(void opaque, const char filename)
		{
		VGAState s = (VGAState )opaque;

		if (!(s->ar_index & 0x20))
		vga_screen_dump_blank(s, filename);
		else if (s->gr[6] & 1)
		vga_screen_dump_graphic(s, filename);
		else
		vga_screen_dump_text(s, filename);
		}