/*
 * Generic Copyin/Copyout routines
 */

#include <stdbool.h>
#include <stdint.h>

#include <errno.h>

#include <sys/kassert.h>
#include <machine/pmap.h>

extern int copy_unsafe(void *to_addr, void *from_addr, uintptr_t len);
extern int copystr_unsafe(void *to_addr, void *from_addr, uintptr_t len);

int
CopyIn(uintptr_t fromuser, void *tokernel, uintptr_t len)
{
    if (len == 0)
	return 0;

    // Kernel space
    if (fromuser >= MEM_USERSPACE_TOP) {
	kprintf("CopyIn: address exceeds userspace top\n");
	return EFAULT;
    }

    // Wrap around
    if (len > (MEM_USERSPACE_TOP - fromuser)) {
	kprintf("CopyIn: length exceeds userspace top\n");
	return EFAULT;
    }

    return copy_unsafe(tokernel, (void *)fromuser, len);
}

int
CopyOut(void *fromkernel, uintptr_t touser, uintptr_t len)
{
    if (len == 0)
	return 0;

    // Kernel space
    if (touser >= MEM_USERSPACE_TOP) {
	kprintf("CopyOut: address exceeds userspace top\n");
	return EFAULT;
    }

    // Wrap around
    if (len > (MEM_USERSPACE_TOP - touser)) {
	kprintf("CopyOut: length exceeds userspace top\n");
	return EFAULT;
    }

    return copy_unsafe((void *)touser, fromkernel, len);
}

int
CopyStrIn(uintptr_t fromuser, void *tokernel, uintptr_t len)
{
    if (len == 0)
	return 0;

    // Kernel space
    if (fromuser >= MEM_USERSPACE_TOP) {
	kprintf("CopyStrIn: address exceeds userspace top\n");
	return EFAULT;
    }

    // Wrap around
    if (len > (MEM_USERSPACE_TOP - fromuser)) {
	kprintf("CopyStrIn: length exceeds userspace top\n");
	return EFAULT;
    }

    return copystr_unsafe(tokernel, (void *)fromuser, len);
}

int
CopyStrOut(void *fromkernel, uintptr_t touser, uintptr_t len)
{
    if (len == 0)
	return 0;

    // Kernel space
    if (touser >= MEM_USERSPACE_TOP) {
	kprintf("CopyStrOut: address exceeds userspace top\n");
	return EFAULT;
    }

    // Wrap around
    if (len > (MEM_USERSPACE_TOP - touser)) {
	kprintf("CopyStrOut: length exceeds userspace top\n");
	return EFAULT;
    }

    return copystr_unsafe((void *)touser, fromkernel, len);
}