static void arch_decomp_setup()

in mach-rpc/include/mach/uncompress.h [112:180]

• 63 lines of code
• 26 McCabe index (conditional complexity)

static void arch_decomp_setup(void)
{
	int i;
	struct tag *t = (struct tag *)params;
	unsigned int nr_pages = 0, page_size = PAGE_SIZE;

	if (t->hdr.tag == ATAG_CORE) {
		for (; t->hdr.size; t = tag_next(t)) {
			if (t->hdr.tag == ATAG_VIDEOTEXT) {
				video_num_rows = t->u.videotext.video_lines;
				video_num_cols = t->u.videotext.video_cols;
				video_x = t->u.videotext.x;
				video_y = t->u.videotext.y;
			} else if (t->hdr.tag == ATAG_VIDEOLFB) {
				bytes_per_char_h = t->u.videolfb.lfb_depth;
				bytes_per_char_v = 8;
			} else if (t->hdr.tag == ATAG_MEM) {
				page_size = PAGE_SIZE;
				nr_pages += (t->u.mem.size / PAGE_SIZE);
			}
		}
	} else {
		nr_pages = params->nr_pages;
		page_size = params->page_size;
		video_num_rows = params->video_num_rows;
		video_num_cols = params->video_num_cols;
		video_x = params->video_x;
		video_y = params->video_y;
		bytes_per_char_h = params->bytes_per_char_h;
		bytes_per_char_v = params->bytes_per_char_v;
	}

	video_size_row = video_num_cols * bytes_per_char_h;
	
	if (bytes_per_char_h == 4)
		for (i = 0; i < 256; i++)
			con_charconvtable[i] =
				(i & 128 ? 1 << 0  : 0) |
				(i & 64  ? 1 << 4  : 0) |
				(i & 32  ? 1 << 8  : 0) |
				(i & 16  ? 1 << 12 : 0) |
				(i & 8   ? 1 << 16 : 0) |
				(i & 4   ? 1 << 20 : 0) |
				(i & 2   ? 1 << 24 : 0) |
				(i & 1   ? 1 << 28 : 0);
	else
		for (i = 0; i < 16; i++)
			con_charconvtable[i] =
				(i & 8   ? 1 << 0  : 0) |
				(i & 4   ? 1 << 8  : 0) |
				(i & 2   ? 1 << 16 : 0) |
				(i & 1   ? 1 << 24 : 0);


	palette_setpixel(0);
	if (bytes_per_char_h == 1) {
		palette_write (0);
		palette_write (0x00ffffff);
		for (i = 2; i < 256; i++)
			palette_write (0);
		white = 1;
	} else {
		for (i = 0; i < 256; i++)
			palette_write (i < 16 ? palette_4[i] : 0);
		white = 7;
	}

	if (nr_pages * page_size < 4096*1024) error("<4M of mem\n");
}