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#include "cookie_cache.h"
#include <time.h>
#include <glib.h>
#include "compat.h"
#include "helpers.h"
#include "poller.h"
#include "str.h"
INLINE void cookie_cache_state_init(struct cookie_cache_state *s) {
bencode_buffer_init(&s->buffer);
s->in_use = g_hash_table_new((GHashFunc) str_hash, (GEqualFunc) str_equal);
s->cookies = g_hash_table_new((GHashFunc) str_hash, (GEqualFunc) str_equal);
}
INLINE void cookie_cache_state_cleanup(struct cookie_cache_state *s) {
g_hash_table_destroy(s->cookies);
g_hash_table_destroy(s->in_use);
bencode_buffer_free(&s->buffer);
}
void cookie_cache_init(struct cookie_cache *c) {
cookie_cache_state_init(&c->current);
cookie_cache_state_init(&c->old);
c->swap_time_us = rtpe_now;
mutex_init(&c->lock);
cond_init(&c->cond);
}
/* lock must be held */
static void __cookie_cache_check_swap(struct cookie_cache *c) {
if (rtpe_now - c->swap_time_us >= 30000000LL) {
g_hash_table_remove_all(c->old.cookies);
bencode_buffer_free(&c->old.buffer);
swap_ptrs(&c->old.cookies, &c->current.cookies);
c->old.buffer = c->current.buffer;
bencode_buffer_init(&c->current.buffer);
c->swap_time_us = rtpe_now;
}
}
static cache_entry *__cache_entry_dup(struct cookie_cache_state *c, const cache_entry *s) {
if (!s)
return NULL;
cache_entry *r;
r = bencode_buffer_alloc(&c->buffer, sizeof(*r));
r->reply = bencode_str_strdup(&c->buffer, &s->reply);
r->command = s->command;
r->callid = bencode_str_strdup(&c->buffer, &s->callid);
return r;
}
cache_entry *cookie_cache_lookup(struct cookie_cache *c, const str *s) {
cache_entry *ret;
LOCK(&c->lock);
__cookie_cache_check_swap(c);
restart:
ret = g_hash_table_lookup(c->current.cookies, s);
if (!ret)
ret = g_hash_table_lookup(c->old.cookies, s);
if (ret) {
ret = cache_entry_dup(ret);
return ret;
}
// is it being worked on right now by another thread?
void *p = g_hash_table_lookup(c->current.in_use, s);
if (!p)
p = g_hash_table_lookup(c->old.in_use, s);
if (p) {
cond_wait(&c->cond, &c->lock);
goto restart;
}
// caller is required to call cookie_cache_insert or cookie_cache_remove
// before `s` runs out of scope
g_hash_table_replace(c->current.in_use, (void *) s, (void *) 0x1);
return NULL;
}
void cookie_cache_insert(struct cookie_cache *c, const str *s, const struct cache_entry *entry) {
LOCK(&c->lock);
g_hash_table_remove(c->current.in_use, s);
g_hash_table_remove(c->old.in_use, s);
g_hash_table_replace(c->current.cookies, bencode_str_str_dup(&c->current.buffer, s),
__cache_entry_dup(&c->current, entry));
g_hash_table_remove(c->old.cookies, s);
cond_broadcast(&c->cond);
}
void cookie_cache_remove(struct cookie_cache *c, const str *s) {
LOCK(&c->lock);
g_hash_table_remove(c->current.in_use, s);
g_hash_table_remove(c->old.in_use, s);
g_hash_table_remove(c->current.cookies, s);
g_hash_table_remove(c->old.cookies, s);
cond_broadcast(&c->cond);
}
void cookie_cache_cleanup(struct cookie_cache *c) {
cookie_cache_state_cleanup(&c->current);
cookie_cache_state_cleanup(&c->old);
}
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