/**
* Invalidate possibly cached page.
*
* This is used when we know a new and fresh copy of the page is held on
* the disk. Further access to the page will require reloading the
* page from disk.
*/
void
lru_invalidate(DBM *db, long bno)
{
struct lru_cache *cache = db->cache;
void *value;
if (
g_hash_table_lookup_extended(cache->pagnum,
ulong_to_pointer(bno), NULL, &value)
) {
long idx = pointer_to_int(value);
g_assert(idx >= 0 && idx < cache->pages);
g_assert(cache->numpag[idx] == bno);
/*
* One should never be invalidating a dirty page, unless something
* went wrong during a split and we're trying to undo things.
* Since the operation will cause a data loss, warn.
*/
if (cache->dirty[idx]) {
g_warning("sdbm: \"%s\": %s() invalidating dirty page #%ld",
db->name, stacktrace_caller_name(1), bno);
}
hash_list_remove(cache->used, value);
g_hash_table_remove(cache->pagnum, ulong_to_pointer(bno));
cache->numpag[idx] = -1;
cache->dirty[idx] = FALSE;
slist_append(cache->available, value); /* Make index available */
}
}
/**
* Expire registered pings.
*
* @param forced TRUE if we're shutdowning and want to cleanup
*/
static void
udp_ping_expire(bool forced)
{
time_t now;
g_return_if_fail(udp_pings);
now = tm_time();
for (;;) {
struct udp_ping *ping;
time_delta_t d;
ping = hash_list_head(udp_pings);
if (NULL == ping)
break;
if (!forced) {
d = delta_time(now, ping->added);
if (d > 0 && d <= UDP_PING_TIMEOUT) {
break;
}
}
if (ping->callback) {
(*ping->callback->cb)(
ping->callback->got_reply ?
UDP_PING_EXPIRED : UDP_PING_TIMEDOUT,
NULL, ping->callback->data);
}
hash_list_remove(udp_pings, ping);
udp_ping_free(ping);
}
}
/**
* Remove cached entry for key, optionally disposing of the whole structure.
* Cached entry is flushed if it was dirty and flush is set.
*
* @return the reusable cached entry if dispose was FALSE and the key was
* indeed cached, NULL otherwise.
*/
static struct cached *
remove_entry(dbmw_t *dw, gconstpointer key, gboolean dispose, gboolean flush)
{
struct cached *old;
gpointer old_key;
gboolean found;
found = map_lookup_extended(dw->values, key, &old_key, (gpointer) &old);
if (!found)
return NULL;
g_assert(old != NULL);
if (old->dirty && flush)
write_back(dw, key, old);
hash_list_remove(dw->keys, key);
map_remove(dw->values, key);
wfree(old_key, dbmw_keylen(dw, old_key));
if (!dispose)
return old;
/*
* Dispose of the cache structure.
*/
free_value(dw, old, TRUE);
WFREE(old);
return NULL;
}
/**
* Make sure the filename associated to a SHA1 is given the name of
* the shared file and no longer bears the name of the partial file.
* This can happen when the partial file is seeded then the file is
* renamed and shared.
*/
void
upload_stats_enforce_local_filename(const shared_file_t *sf)
{
struct ul_stats *s;
const struct sha1 *sha1;
const char *name;
if (!upload_stats_by_sha1)
return; /* Nothing known by SHA1 yet */
sha1 = sha1_hash_available(sf) ? shared_file_sha1(sf) : NULL;
if (!sha1)
return; /* File's SHA1 not known yet, nothing to do here */
s = g_hash_table_lookup(upload_stats_by_sha1, sha1);
if (NULL == s)
return; /* SHA1 not in stats, nothing to do */
name = shared_file_name_nfc(sf);
if (name == s->filename) /* Both are string atoms */
return; /* Everything is fine */
/*
* We need to update the filename to match the shared file.
*/
hash_list_remove(upload_stats_list, s);
atom_str_change(&s->pathname, shared_file_path(sf));
atom_str_change(&s->filename, name);
hash_list_append(upload_stats_list, s);
gcu_upload_stats_gui_update_name(s);
}
/**
* Callout queue callback fired when waiting event times out.
*/
static void
wq_timed_out(cqueue_t *cq, void *arg)
{
wq_event_t *we = arg;
hash_list_t *hl;
wq_status_t status;
wq_event_check(we);
g_assert(we->tm != NULL);
cq_zero(cq, &we->tm->timeout_ev);
hl = htable_lookup(waitqueue, we->key);
g_assert(hl != NULL);
/*
* Invoke the callback with the sentinel data signalling a timeout.
*/
status = (*we->cb)(we->arg, WQ_TIMED_OUT);
/*
* When the callback returns WQ_SLEEP, we re-instantiate the initial
* timeout.
*
* Otherwise the event is discarded (removed from the wait queue) and
* the callback will never be invoked again for this event.
*/
switch (status) {
case WQ_SLEEP:
we->tm->timeout_ev = cq_main_insert(we->tm->delay, wq_timed_out, we);
return;
case WQ_EXCLUSIVE:
s_critical("weird status WQ_EXCLUSIVE on timeout invocation of %s()",
stacktrace_function_name(we->cb));
/* FALL THROUGH */
case WQ_REMOVE:
hash_list_remove(hl, we);
/*
* Cleanup the table if it ends-up being empty.
*/
if (0 == hash_list_length(hl)) {
hash_list_free(&hl);
htable_remove(waitqueue, we->key);
}
wq_event_free(we);
return;
}
g_assert_not_reached();
}
/**
* @return NULL on error, a newly allocated string via halloc() otherwise.
*/
static char *
uhc_get_next(void)
{
struct uhc *uhc;
char *host;
time_t now;
size_t n;
g_return_val_if_fail(uhc_list, NULL);
now = tm_time();
n = hash_list_count(uhc_list);
if (0 == n)
return NULL;
/*
* Wait UHC_RETRY_AFTER secs before contacting the UHC again.
* Can't be too long because the UDP reply may get lost if the
* requesting host already has a saturated b/w.
* If we come here, it's because we're lacking hosts for establishing
* a Gnutella connection, after we exhausted our caches.
*/
while (n-- != 0) {
uhc = hash_list_head(uhc_list);
g_assert(uhc != NULL); /* We computed count on entry */
if (delta_time(now, uhc->stamp) >= UHC_RETRY_AFTER)
goto found;
hash_list_moveto_tail(uhc_list, uhc);
}
return NULL;
found:
uhc->stamp = now;
host = h_strdup(uhc->host);
if (uhc->used < UHC_MAX_ATTEMPTS) {
uhc->used++;
hash_list_moveto_tail(uhc_list, uhc);
} else {
hash_list_remove(uhc_list, uhc);
uhc_free(&uhc);
}
return host;
}
/**
* Detach a UDP TX scheduling layer from a TX stack.
*
* @param us the UDP TX scheduler to detach from
* @param tx the TX driver detaching from the scheduler
*/
void
udp_sched_detach(udp_sched_t *us, const txdrv_t *tx)
{
struct udp_tx_stack key, *uts;
const void *oldkey;
udp_sched_check(us);
key.tx = tx;
g_assert(hash_list_contains(us->stacks, &key));
hash_list_find(us->stacks, &key, &oldkey);
uts = deconstify_pointer(oldkey);
hash_list_remove(us->stacks, uts);
WFREE(uts);
}
/**
* Remove an attribute from the table.
*
* The key is only used for lookups, only the hashed elements need to be
* filled in.
*
* @return TRUE if we found the attribute and removed it.
*/
static bool
xattr_table_remove_key(xattr_table_t *xat, const struct xattr *key)
{
struct xattr *old;
xattr_table_check(xat);
g_assert(key != NULL);
old = xattr_table_lookup_key(xat, key);
if (old != NULL) {
hash_list_remove(xat->hl, old);
xattr_free(old);
return TRUE;
} else {
return FALSE;
}
}
/**
* Map iterator to free cached entries that have been marked as removable.
*/
static gboolean
cache_free_removable(gpointer key, gpointer value, gpointer data)
{
dbmw_t *dw = data;
struct cached *entry = value;
dbmw_check(dw);
g_assert(!entry->len == !entry->data);
if (!entry->removable)
return FALSE;
free_value(dw, entry, TRUE);
hash_list_remove(dw->keys, key);
wfree(key, dbmw_keylen(dw, key));
WFREE(entry);
return TRUE;
}
/**
* Remove a key from the table.
*
* @return TRUE if the key was found and removed.
*/
bool
ohash_table_remove(ohash_table_t *oh, const void *key)
{
struct ohash_pair pk;
struct ohash_pair *op;
ohash_table_check(oh);
pk.oh = oh;
pk.key = key;
if (!hash_list_contains(oh->hl, &pk))
return FALSE;
op = hash_list_remove(oh->hl, &pk);
g_assert(op->oh == oh);
ohash_free_kv(op);
return TRUE;
}
/**
* Clear all the upload stats data structure.
*/
static G_GNUC_COLD void
upload_stats_free_all(void)
{
if (upload_stats_list) {
struct ul_stats *s;
while (NULL != (s = hash_list_head(upload_stats_list))) {
hash_list_remove(upload_stats_list, s);
atom_str_free_null(&s->pathname);
atom_str_free_null(&s->filename);
if (s->sha1)
g_hash_table_remove(upload_stats_by_sha1, s->sha1);
atom_sha1_free_null(&s->sha1);
WFREE(s);
}
hash_list_free(&upload_stats_list);
gm_hash_table_destroy_null(&upload_stats_by_sha1);
}
dirty = TRUE;
}
/**
* Remove an event from the queue.
*/
static void
wq_remove(wq_event_t *we)
{
hash_list_t *hl;
wq_event_check(we);
hl = htable_lookup(waitqueue, we->key);
if (NULL == hl) {
s_critical("attempt to remove event %s() on unknown key %p",
stacktrace_function_name(we->cb), we->key);
} if (NULL == hash_list_remove(hl, we)) {
s_critical("attempt to remove unknown event %s() on %p",
stacktrace_function_name(we->cb), we->key);
} else if (0 == hash_list_length(hl)) {
hash_list_free(&hl);
htable_remove(waitqueue, we->key);
}
wq_event_free(we);
}
/**
* Remove cached entry for key, optionally disposing of the whole structure.
* Cached entry is flushed if it was dirty and flush is set.
*
* @return the reusable cached entry if dispose was FALSE and the key was
* indeed cached, NULL otherwise.
*/
static struct cached *
remove_entry(dbmw_t *dw, const void *key, bool dispose, bool flush)
{
struct cached *old;
void *old_key;
bool found;
found = map_lookup_extended(dw->values, key, &old_key, (void *) &old);
if (!found)
return NULL;
g_assert(old != NULL);
if (dbg_ds_debugging(dw->dbg, 3, DBG_DSF_CACHING)) {
dbg_ds_log(dw->dbg, dw, "%s: %s key=%s (%s)",
G_STRFUNC, old->dirty ? "dirty" : "clean",
dbg_ds_keystr(dw->dbg, key, (size_t) -1),
flush ? "flushing" : " discarding");
}
if (old->dirty && flush)
write_back(dw, key, old);
hash_list_remove(dw->keys, key);
map_remove(dw->values, key);
wfree(old_key, dbmw_keylen(dw, old_key));
if (!dispose)
return old;
/*
* Dispose of the cache structure.
*/
free_value(dw, old, TRUE);
WFREE(old);
return NULL;
}
/**
* Upon reception of an UDP pong, check whether we had a matching registered
* ping bearing the given MUID.
*
* If there was a callback atttached to the reception of a reply, invoke it
* before returning UDP_PONG_HANDLED.
*
* The ``host'' paramaeter MUST be a stack or static pointer to a gnet_host_t,
* and NOT the address of a dynamically allocated host because gnet_host_copy()
* is going to be used on it.
*
* @param n the gnutella node replying
* @param host if non-NULL, filled with the host to whom we sent the ping
*
* @return TRUE if indeed this was a reply for a ping we sent.
*/
enum udp_pong_status
udp_ping_is_registered(const struct gnutella_node *n, gnet_host_t *host)
{
const struct guid *muid = gnutella_header_get_muid(&n->header);
if (udp_pings) {
struct udp_ping *ping;
ping = hash_list_remove(udp_pings, muid);
if (ping != NULL) {
if (host != NULL) {
/*
* Let caller know the exact IP:port of the host we contacted,
* since the replying party can use a different port (which
* we may not be able to contact, whereas we know the targeted
* port did cause a reply).
*/
gnet_host_copy(host, ping->host);
}
if (ping->callback) {
(*ping->callback->cb)(UDP_PING_REPLY, n, ping->callback->data);
if (ping->callback->multiple) {
ping->callback->got_reply = TRUE;
ping->added = tm_time(); /* Delay expiration */
hash_list_append(udp_pings, ping);
} else {
udp_ping_free(ping);
}
return UDP_PONG_HANDLED;
}
udp_ping_free(ping);
return UDP_PONG_SOLICITED;
}
}
return UDP_PONG_UNSOLICITED;
}
/**
* Callback for adns_resolve(), invoked when the resolution is complete.
*/
static void
uhc_host_resolved(const host_addr_t *addrs, size_t n, void *uu_udata)
{
(void) uu_udata;
g_assert(addrs);
/*
* If resolution failed, try again if possible.
*/
if (0 == n) {
if (GNET_PROPERTY(bootstrap_debug))
g_warning("could not resolve UDP host cache \"%s\"",
uhc_ctx.host);
uhc_try_next();
return;
}
if (n > 1) {
size_t i;
host_addr_t *hav;
/* Current UHC was moved to tail by uhc_get_next() */
struct uhc *uhc = hash_list_tail(uhc_list);
/*
* UHC resolved to multiple endpoints. Could be roundrobbin or
* IPv4 and IPv6 addresss. Adding them as seperate entries: if the
* IPv6 is unreachable we have an opportunity to skip it.
* -- JA 24/7/2011
*
* Shuffle the address array before appending them to the UHC list.
* --RAM, 2015-10-01
*/
hav = HCOPY_ARRAY(addrs, n);
SHUFFLE_ARRAY_N(hav, n);
for (i = 0; i < n; i++) {
const char *host = host_addr_port_to_string(hav[i], uhc_ctx.port);
g_debug("BOOT UDP host cache \"%s\" resolved to %s (#%zu)",
uhc_ctx.host, host, i + 1);
uhc_list_append(host);
}
hash_list_remove(uhc_list, uhc); /* Replaced by IP address list */
uhc_free(&uhc);
/*
* We're going to continue and process the first address (in our
* shuffled array). Make sure it is put at the end of the list
* and marked as being used, mimicing what uhc_get_next() would do.
* --RAM, 2015-10-01
*/
{
struct uhc key;
key.host = host_addr_port_to_string(hav[0], uhc_ctx.port);
uhc = hash_list_lookup(uhc_list, &key);
g_assert(uhc != NULL); /* We added the entry above! */
uhc->stamp = tm_time();
uhc->used++;
hash_list_moveto_tail(uhc_list, uhc);
}
uhc_ctx.addr = hav[0]; /* Struct copy */
HFREE_NULL(hav);
} else {
uhc_ctx.addr = addrs[0];
}
if (GNET_PROPERTY(bootstrap_debug))
g_debug("BOOT UDP host cache \"%s\" resolved to %s",
uhc_ctx.host, host_addr_to_string(uhc_ctx.addr));
/*
* Now send the ping.
*/
uhc_send_ping();
}
