static int __init pnpbios_probe_system()

in pnpbios/core.c [423:475]

• 45 lines of code
• 7 McCabe index (conditional complexity)

static int __init pnpbios_probe_system(void)
{
	union pnp_bios_install_struct *check;
	u8 sum;
	int length, i;

	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");

	/*
	 * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
	 * structure and, if one is found, sets up the selectors and
	 * entry points
	 */
	for (check = (union pnp_bios_install_struct *)__va(0xf0000);
	     check < (union pnp_bios_install_struct *)__va(0xffff0);
	     check = (void *)check + 16) {
		if (check->fields.signature != PNP_SIGNATURE)
			continue;
		printk(KERN_INFO
		       "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
		       check);
		length = check->fields.length;
		if (!length) {
			printk(KERN_ERR
			       "PnPBIOS: installation structure is invalid, skipping\n");
			continue;
		}
		for (sum = 0, i = 0; i < length; i++)
			sum += check->chars[i];
		if (sum) {
			printk(KERN_ERR
			       "PnPBIOS: installation structure is corrupted, skipping\n");
			continue;
		}
		if (check->fields.version < 0x10) {
			printk(KERN_WARNING
			       "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
			       check->fields.version >> 4,
			       check->fields.version & 15);
			continue;
		}
		printk(KERN_INFO
		       "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
		       check->fields.version >> 4, check->fields.version & 15,
		       check->fields.pm16cseg, check->fields.pm16offset,
		       check->fields.pm16dseg);
		pnp_bios_install = check;
		return 1;
	}

	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
	return 0;
}