From Ben Gras, add select support on /dev/random.

Change-Id: I47bf4c45285458ecc224df0564edf98afdb2c9d6
This commit is contained in:
Lionel Sambuc 2014-04-16 13:57:52 +02:00
parent 78cfc9712b
commit 6a309697f4

View file

@ -28,15 +28,20 @@ static ssize_t r_write(devminor_t minor, u64_t position, endpoint_t endpt,
static int r_open(devminor_t minor, int access, endpoint_t user_endpt);
static void r_random(clock_t stamp);
static void r_updatebin(int source, struct k_randomness_bin *rb);
static int r_select(devminor_t, unsigned int, endpoint_t);
/* Entry points to this driver. */
static struct chardriver r_dtab = {
.cdr_open = r_open, /* open device */
.cdr_read = r_read, /* read from device */
.cdr_write = r_write, /* write to device (seeding it) */
.cdr_select = r_select, /* select hook */
.cdr_alarm = r_random /* get randomness from kernel (alarm) */
};
/* select requestor */
static endpoint_t random_select = NONE;
/* Buffer for the /dev/random number generator. */
#define RANDOM_BUF_SIZE 1024
static char random_buf[RANDOM_BUF_SIZE];
@ -253,3 +258,16 @@ static void r_random(clock_t UNUSED(stamp))
printf("RANDOM: sys_setalarm failed: %d\n", s);
}
/*===========================================================================*
* r_select *
*===========================================================================*/
static int r_select(devminor_t minor, unsigned int ops, endpoint_t ep)
{
/* random device is always writable; it's infinitely readable
* once seeded, and doesn't block when it's not, so all operations
* are instantly possible. we ignore CDEV_OP_ERR.
*/
int ready_ops = 0;
if (minor != RANDOM_DEV) return(EIO);
return ops & (CDEV_OP_RD | CDEV_OP_WR);
}