/*
* Returns a pseudo-random number in [min, max].
*/
int
rand_between(int min, int max)
{
int r = rand();
kdebug_assert(min >= 0);
kdebug_assert(max >= min);
while (r < min || r > max)
{
r = rand();
}
return r;
}
/* kexception:
* Application-specific exception handler, called after registers
* have been saved.
*/
void
kexception()
{
registers_t * reg;
cause_reg_t cause;
/* Make sure that we are here because of a syscall exception. */
cause.reg = kget_cause();
kdebug_assert(cause.field.exc == 8);
/* Get pointer to stored registers. */
reg = kget_registers();
/* Handle the system call (see syscall.S). */
ksyscall_handler(reg);
/* Return from exception to instruction following syscall. */
reg->epc_reg += 4;
/* Acknowledge syscall exception. */
kset_cause(~0x60, 0);
}
/* example of call to a print function */
printstr(a);
/* Put '0' on the Malta display. */
display_word(0);
/* Setup storage-area for saving registers on exception. */
kset_registers(®s);
/* Initialise timer to interrupt in 100 ms (simulated time). */
kload_timer(100 * timer_msec);
/* Update the status register to enable timer interrupts. */
kset_sr(0xFFBF00E8, 0x10008001);
/* Forever do nothing. */
while (1);
}
/*
* Releases a list node back to the system. Always returns NULL, to make it
* easy to avoid dangling pointers by simply using the return value in an
* assignment.
*/
list_node_t *
list_node_free(list_node_t *node)
{
kdebug_assert(node);
node->next_free = g_freelist;
g_freelist = node;
return NULL;
}
/*
* See stdlib.h documentation.
*/
int
atoi(const char *str)
{
int x = 0;
int i = 0;
int j = 1;
int k = 0;
kdebug_assert(str);
/* Skip white space */
while (str[i] == ' ')
{
i++;
}
if (str[i] == '-' || str[i] == '+')
{
i++;
}
/* index of start */
k = i;
/* 0-9 = 48-57 */
while (str[i] >= '0' && str[i] <= '9')
{
i++;
}
/* remove last char \0 */
i--;
for ( ; i >= k; i--)
{
x += (str[i] - '0') * j;
j *= 10;
}
if (str[i] == '-')
{
x = -x;
}
return x;
}
