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#include "job.h"
#include "utils.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>
#include <sys/socket.h>
#include <glib/gslist.h>
#define DEV_STRLEN 12 // INCLUDING NULLCHAR (increase to 13 if you need more than 100 (0-99) devices)
#define MAX_NUM_DEVICES_TO_CHECK 100
#ifndef FALSE
#define FALSE (0)
#endif
#ifndef TRUE
#define TRUE (!FALSE)
#endif
typedef struct
{
char available;
char name[DEV_STRLEN];
} device_t;
// "/dev/dnbdXX" == 11 bytes per device + nullchar = 12
static device_t *devices = NULL;
static int num_devices = 0;
static char keep_running = TRUE;
// Private functions
static char* get_free_device();
static void query_servers();
//
void* dnbd3_job_thread(void *data)
{
int i, j;
// Determine number of available dnbd3 devices, which are needed for proxy mode
char dev[DEV_STRLEN];
for (i = 0; i < MAX_NUM_DEVICES_TO_CHECK; ++i)
{
snprintf(dev, DEV_STRLEN, "/dev/dnbd%d", i);
if (access(dev, W_OK | R_OK)) // Need RW access to device to read and do ioctl
continue;
++num_devices;
}
if (num_devices > 0)
{
devices = calloc(num_devices, sizeof(*devices));
for (i = 0, j = 0; i < MAX_NUM_DEVICES_TO_CHECK; ++i)
{
memset(dev, 0, DEV_STRLEN);
snprintf(dev, DEV_STRLEN, "/dev/dnbd%d", i);
if (access(dev, W_OK | R_OK))
continue;
if (j >= num_devices) // More available devices during second iteration? :-(
break;
memcpy(devices[j].name, dev, DEV_STRLEN);
devices[j].available = TRUE;
++j;
}
}
//
time_t next_delete_invocation = 0;
//
// Job/Watchdog mainloop
while (keep_running)
{
const time_t starttime = time(NULL);
//
// TODO: Update image atime
// Call image deletion function if last call is more than 5 minutes ago
if (starttime < next_delete_invocation)
{
next_delete_invocation = starttime + 300;
dnbd3_exec_delete(TRUE);
}
// TODO: Replicate proxied images (limited bandwidth)
// Query other servers for new images/status/...
query_servers();
// TODO: Switch server of dnbd device based on more sophisticated inputs than just rtt
// Calc sleep timeout for next iteration
sleep(30 - (time(NULL) - starttime)); // Sleep 30 seconds, but account for the time it took to execute the loop
}
//
free(devices);
devices = NULL;
pthread_exit(NULL);
return NULL;
}
void dnbd3_job_shutdown()
{
keep_running = FALSE;
}
static void query_servers()
{
struct timeval client_timeout;
client_timeout.tv_sec = 0;
client_timeout.tv_usec = 500 * 1000;
int client_sock;
// Apply read/write timeout
setsockopt(client_sock, SOL_SOCKET, SO_RCVTIMEO, &client_timeout, sizeof(client_timeout));
setsockopt(client_sock, SOL_SOCKET, SO_SNDTIMEO, &client_timeout, sizeof(client_timeout));
}
/**
* Get full name of an available dnbd3 device, eg. /dev/dnbd4
* Returned buffer is owned by this module, do not modify or free!
*/
static char* get_free_device()
{
if (devices == NULL)
return NULL;
int i;
for (i = 0; i < num_devices; ++i)
{
if (!devices[i].available)
continue;
// TODO: Check sysfs if device is maybe already connected
return devices[i].name;
}
return NULL;
}
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