Fix feasibility distance maintenance

This commit is contained in:
Matthias Schiffer 2012-10-06 04:13:01 +02:00
parent cebdfe45e9
commit 7601e58284
3 changed files with 56 additions and 47 deletions

View file

@ -28,20 +28,6 @@
#include "neigh.h"
bool ffd_is_feasible(const ffd_announce_t *announce, ffd_metric_seqno_t ms) {
if (FFD_IS_INFINITY(ms) || FFD_IS_INFINITY(announce->feasibility_distance))
return true;
int16_t seqno_diff = ms.seqno - announce->feasibility_distance.seqno;
if (seqno_diff < 0)
return true;
if (seqno_diff == 0 && ms.metric < announce->feasibility_distance.metric)
return true;
return false;
}
static ffd_nexthop_t* select_nexthop(const ffd_announce_t *announce) {
uint16_t ret_metric = 0xffff;
ffd_nexthop_t *ret = NULL;
@ -62,7 +48,7 @@ static ffd_nexthop_t* select_nexthop(const ffd_announce_t *announce) {
return ret;
}
ffd_metric_seqno_t ffd_announce_get_metric(const ffd_announce_t *announce) {
ffd_metric_seqno_t get_metric(const ffd_announce_t *announce) {
if (announce->selected) {
uint32_t metric = announce->selected->metric_seqno.metric + ffd_neigh_get_cost(announce->selected->neigh);
@ -75,6 +61,7 @@ ffd_metric_seqno_t ffd_announce_get_metric(const ffd_announce_t *announce) {
static inline void update_selected(ffd_announce_t *announce) {
announce->selected = select_nexthop(announce);
announce->metric = get_metric(announce);
}
void ffd_announce_update(ffd_announce_t *announce, ffd_nexthop_t *nexthop, ffd_metric_seqno_t ms, uint16_t interval) {
@ -90,7 +77,7 @@ void ffd_announce_update(ffd_announce_t *announce, ffd_nexthop_t *nexthop, ffd_m
ffd_announce_t* ffd_announce_new(void) {
ffd_announce_t *a = calloc(1, sizeof(ffd_announce_t));
a->feasibility_distance.metric = 0xffff;
a->metric.metric = a->feasibility_distance.metric = 0xffff;
a->next = announce_list;
announce_list = a;

View file

@ -50,35 +50,11 @@ typedef struct __attribute__((packed)) _ffd_node_id_t {
uint8_t id[8];
} ffd_node_id_t;
#define FFD_NODE_ID_UNSPEC ((ffd_node_id_t){})
static inline bool ffd_is_node_id_unspec(const ffd_node_id_t *node) {
const uint8_t *id = node->id;
if (id[0]||id[1]||id[2]||id[3]||id[4]||id[5]||id[6]||id[7])
return false;
else
return true;
}
static inline bool ffd_are_node_ids_equal(const ffd_node_id_t *id1, const ffd_node_id_t *id2) {
const uint8_t *a = id1->id;
const uint8_t *b = id2->id;
return (a[0]==b[0] && a[1]==b[1] && a[2]==b[2] && a[3]==b[3]
&& a[4]==b[4] && a[5]==b[5] && a[6]==b[6] && a[7]==b[7]);
}
typedef struct _ffd_metric_seqno_t {
uint16_t metric;
uint16_t seqno;
} ffd_metric_seqno_t;
#define FFD_IS_INFINITY(m) ((m).metric == 0xffff)
typedef struct _ffd_nexthop_t {
struct _ffd_nexthop_t *next;
@ -96,6 +72,7 @@ typedef struct _ffd_announce_t {
uint16_t type;
uint16_t key;
ffd_metric_seqno_t metric;
ffd_metric_seqno_t feasibility_distance;
ffd_nexthop_t *selected;
@ -147,8 +124,54 @@ extern int sockfd;
extern struct timespec now;
bool ffd_is_feasible(const ffd_announce_t *announce, ffd_metric_seqno_t ms);
ffd_metric_seqno_t ffd_announce_get_metric(const ffd_announce_t *announce);
#define FFD_NODE_ID_UNSPEC ((ffd_node_id_t){})
static inline bool ffd_is_node_id_unspec(const ffd_node_id_t *node) {
const uint8_t *id = node->id;
if (id[0]||id[1]||id[2]||id[3]||id[4]||id[5]||id[6]||id[7])
return false;
else
return true;
}
static inline bool ffd_are_node_ids_equal(const ffd_node_id_t *id1, const ffd_node_id_t *id2) {
const uint8_t *a = id1->id;
const uint8_t *b = id2->id;
return (a[0]==b[0] && a[1]==b[1] && a[2]==b[2] && a[3]==b[3]
&& a[4]==b[4] && a[5]==b[5] && a[6]==b[6] && a[7]==b[7]);
}
#define FFD_IS_INFINITY(m) ((m).metric == 0xffff)
/* returns true if ms1 is better than ms2 */
static inline bool ffd_is_metric_better(ffd_metric_seqno_t ms1, ffd_metric_seqno_t ms2) {
if (FFD_IS_INFINITY(ms1))
return false;
if (FFD_IS_INFINITY(ms2))
return true;
int16_t seqno_diff = ms2.seqno - ms1.seqno;
if (seqno_diff < 0)
return true;
if (seqno_diff == 0 && ms1.metric < ms2.metric)
return true;
return false;
}
static inline bool ffd_is_feasible(const ffd_announce_t *announce, ffd_metric_seqno_t ms) {
if (FFD_IS_INFINITY(ms))
return true;
return ffd_is_metric_better(ms, announce->feasibility_distance);
}
void ffd_announce_update(ffd_announce_t *announce, ffd_nexthop_t *nexthop, ffd_metric_seqno_t ms, uint16_t interval);
ffd_announce_t* ffd_announce_new(void);

View file

@ -164,13 +164,11 @@ static bool add_update(ffd_packet_t *packet, size_t max_len, ffd_node_id_t *node
return false;
}
ffd_metric_seqno_t metric = ffd_announce_get_metric(announce);
update->flags = 0;
update->reserved = 0;
update->interval = htons(FFD_UPDATE_INTERVAL);
update->seqno = htons(metric.seqno);
update->metric = htons(metric.metric);
update->seqno = htons(announce->metric.seqno);
update->metric = htons(announce->metric.metric);
update->type = htons(announce->type);
update->key = htons(announce->key);
@ -182,7 +180,8 @@ static bool add_update(ffd_packet_t *packet, size_t max_len, ffd_node_id_t *node
}
}
announce->feasibility_distance = metric;
if (ffd_is_metric_better(announce->metric, announce->feasibility_distance))
announce->feasibility_distance = announce->metric;
return true;
}