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#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <pthread.h>
#include <talloc.h>
#include <osmocom/core/linuxlist.h>
#include "bankd.h"
/* thread-safe lookup of map by client:slot */
struct bankd_slot_mapping *bankd_slotmap_by_client(struct bankd *bankd, const struct client_slot *client)
{
struct bankd_slot_mapping *map;
pthread_rwlock_rdlock(&bankd->slot_mappings_rwlock);
llist_for_each_entry(map, &bankd->slot_mappings, list) {
if (client_slot_equals(&map->client, client)) {
pthread_rwlock_unlock(&bankd->slot_mappings_rwlock);
return map;
}
}
pthread_rwlock_unlock(&bankd->slot_mappings_rwlock);
return NULL;
}
/* thread-safe lookup of map by bank:slot */
struct bankd_slot_mapping *bankd_slotmap_by_bank(struct bankd *bankd, const struct bank_slot *bank)
{
struct bankd_slot_mapping *map;
pthread_rwlock_rdlock(&bankd->slot_mappings_rwlock);
llist_for_each_entry(map, &bankd->slot_mappings, list) {
if (bank_slot_equals(&map->bank, bank)) {
pthread_rwlock_unlock(&bankd->slot_mappings_rwlock);
return map;
}
}
pthread_rwlock_unlock(&bankd->slot_mappings_rwlock);
return NULL;
}
/* thread-safe creating of a new bank<->client map */
int bankd_slotmap_add(struct bankd *bankd, const struct bank_slot *bank, const struct client_slot *client)
{
struct bankd_slot_mapping *map;
/* We assume a single thread (main thread) will ever update the mappings,
* and hence we don't have any races by first grabbing + releasing the read
* lock twice before grabbing the writelock below */
map = bankd_slotmap_by_bank(bankd, bank);
if (map) {
fprintf(stderr, "BANKD %u:%u already in use, cannot add new map\n",
bank->bank_id, bank->slot_nr);
return -EBUSY;
}
map = bankd_slotmap_by_client(bankd, client);
if (map) {
fprintf(stderr, "CLIENT %u:%u already in use, cannot add new map\n",
client->client_id, client->slot_nr);
return -EBUSY;
}
/* allocate new mapping and add to list of mappings */
map = talloc_zero(bankd, struct bankd_slot_mapping);
if (!map)
return -ENOMEM;
map->bank = *bank;
map->client = *client;
pthread_rwlock_wrlock(&bankd->slot_mappings_rwlock);
llist_add_tail(&map->list, &bankd->slot_mappings);
pthread_rwlock_unlock(&bankd->slot_mappings_rwlock);
printf("Added Slot Map C(%u:%u) <-> B(%u:%u)\n",
map->client.client_id, map->client.slot_nr, map->bank.bank_id, map->bank.slot_nr);
return 0;
}
/* thread-safe removal of a bank<->client map */
void bankd_slotmap_del(struct bankd *bankd, struct bankd_slot_mapping *map)
{
printf("Deleting Slot Map C(%u:%u) <-> B(%u:%u)\n",
map->client.client_id, map->client.slot_nr, map->bank.bank_id, map->bank.slot_nr);
pthread_rwlock_wrlock(&bankd->slot_mappings_rwlock);
llist_del(&map->list);
pthread_rwlock_unlock(&bankd->slot_mappings_rwlock);
talloc_free(map);
}
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