static int ptrace_peekusr()

in kernel/ptrace.c [270:335]

• 50 lines of code
• 12 McCabe index (conditional complexity)

static int ptrace_peekusr(struct task_struct *child, long regno,
			  long __user *ret)
{
	struct pt_regs *regs;
	unsigned long tmp;

	regs = task_pt_regs(child);
	tmp = 0;  /* Default return value. */

	switch(regno) {
	case REG_AR_BASE ... REG_AR_BASE + XCHAL_NUM_AREGS - 1:
		tmp = regs->areg[regno - REG_AR_BASE];
		break;

	case REG_A_BASE ... REG_A_BASE + 15:
		tmp = regs->areg[regno - REG_A_BASE];
		break;

	case REG_PC:
		tmp = regs->pc;
		break;

	case REG_PS:
		/* Note: PS.EXCM is not set while user task is running;
		 * its being set in regs is for exception handling
		 * convenience.
		 */
		tmp = (regs->ps & ~(1 << PS_EXCM_BIT));
		break;

	case REG_WB:
		break;		/* tmp = 0 */

	case REG_WS:
		{
			unsigned long wb = regs->windowbase;
			unsigned long ws = regs->windowstart;
			tmp = ((ws >> wb) | (ws << (WSBITS - wb))) &
				((1 << WSBITS) - 1);
			break;
		}
	case REG_LBEG:
		tmp = regs->lbeg;
		break;

	case REG_LEND:
		tmp = regs->lend;
		break;

	case REG_LCOUNT:
		tmp = regs->lcount;
		break;

	case REG_SAR:
		tmp = regs->sar;
		break;

	case SYSCALL_NR:
		tmp = regs->syscall;
		break;

	default:
		return -EIO;
	}
	return put_user(tmp, ret);
}