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dbcdacc58d
We know that we want to put something into _notrans, no point in doing another round trip into gencache.tdb. Signed-off-by: Volker Lendecke <vl@samba.org> Reviewed-by: Ralph Boehme <slow@samba.org>
1000 lines
22 KiB
C
1000 lines
22 KiB
C
/*
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Unix SMB/CIFS implementation.
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Generic, persistent and shared between processes cache mechanism for use
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by various parts of the Samba code
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Copyright (C) Rafal Szczesniak 2002
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Copyright (C) Volker Lendecke 2009
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "includes.h"
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#include "system/filesys.h"
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#include "system/glob.h"
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#include "util_tdb.h"
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#include "tdb_wrap/tdb_wrap.h"
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#undef DBGC_CLASS
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#define DBGC_CLASS DBGC_TDB
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#define CACHE_DATA_FMT "%12u/"
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static struct tdb_wrap *cache;
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static struct tdb_wrap *cache_notrans;
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/**
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* @file gencache.c
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* @brief Generic, persistent and shared between processes cache mechanism
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* for use by various parts of the Samba code
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*
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**/
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/**
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* Cache initialisation function. Opens cache tdb file or creates
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* it if does not exist.
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*
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* @return true on successful initialisation of the cache or
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* false on failure
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**/
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static bool gencache_init(void)
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{
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char* cache_fname = NULL;
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int open_flags = O_RDWR|O_CREAT;
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/* skip file open if it's already opened */
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if (cache) {
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return true;
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}
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cache_fname = cache_path("gencache.tdb");
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if (cache_fname == NULL) {
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return false;
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}
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DEBUG(5, ("Opening cache file at %s\n", cache_fname));
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cache = tdb_wrap_open(NULL, cache_fname, 0,
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TDB_DEFAULT|TDB_INCOMPATIBLE_HASH,
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open_flags, 0644);
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if (cache) {
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int ret;
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ret = tdb_check(cache->tdb, NULL, NULL);
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if (ret != 0) {
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TALLOC_FREE(cache);
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/*
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* Retry with CLEAR_IF_FIRST.
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*
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* Warning: Converting this to dbwrap won't work
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* directly. gencache.c does transactions on this tdb,
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* and dbwrap forbids this for CLEAR_IF_FIRST
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* databases. tdb does allow transactions on
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* CLEAR_IF_FIRST databases, so lets use it here to
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* clean up a broken database.
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*/
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cache = tdb_wrap_open(NULL, cache_fname, 0,
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TDB_DEFAULT|
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TDB_INCOMPATIBLE_HASH|
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TDB_CLEAR_IF_FIRST,
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open_flags, 0644);
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}
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}
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if (!cache && (errno == EACCES)) {
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open_flags = O_RDONLY;
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cache = tdb_wrap_open(NULL, cache_fname, 0,
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TDB_DEFAULT|TDB_INCOMPATIBLE_HASH,
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open_flags, 0644);
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if (cache) {
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DEBUG(5, ("gencache_init: Opening cache file %s read-only.\n", cache_fname));
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}
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}
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TALLOC_FREE(cache_fname);
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if (!cache) {
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DEBUG(5, ("Attempt to open gencache.tdb has failed.\n"));
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return false;
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}
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cache_fname = lock_path("gencache_notrans.tdb");
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if (cache_fname == NULL) {
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TALLOC_FREE(cache);
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return false;
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}
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DEBUG(5, ("Opening cache file at %s\n", cache_fname));
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cache_notrans = tdb_wrap_open(NULL, cache_fname, 0,
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TDB_CLEAR_IF_FIRST|
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TDB_INCOMPATIBLE_HASH|
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TDB_NOSYNC|
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TDB_MUTEX_LOCKING,
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open_flags, 0644);
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if (cache_notrans == NULL) {
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DEBUG(5, ("Opening %s failed: %s\n", cache_fname,
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strerror(errno)));
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TALLOC_FREE(cache_fname);
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TALLOC_FREE(cache);
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return false;
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}
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TALLOC_FREE(cache_fname);
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return true;
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}
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static TDB_DATA last_stabilize_key(void)
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{
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TDB_DATA result;
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result.dptr = discard_const_p(uint8_t, "@LAST_STABILIZED");
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result.dsize = 17;
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return result;
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}
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struct gencache_have_val_state {
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time_t new_timeout;
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const DATA_BLOB *data;
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bool gotit;
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};
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static void gencache_have_val_parser(time_t old_timeout, DATA_BLOB data,
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void *private_data)
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{
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struct gencache_have_val_state *state =
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(struct gencache_have_val_state *)private_data;
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time_t now = time(NULL);
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int cache_time_left, new_time_left, additional_time;
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/*
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* Excuse the many variables, but these time calculations are
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* confusing to me. We do not want to write to gencache with a
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* possibly expensive transaction if we are about to write the same
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* value, just extending the remaining timeout by less than 10%.
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*/
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cache_time_left = old_timeout - now;
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if (cache_time_left <= 0) {
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/*
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* timed out, write new value
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*/
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return;
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}
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new_time_left = state->new_timeout - now;
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if (new_time_left <= 0) {
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/*
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* Huh -- no new timeout?? Write it.
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*/
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return;
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}
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if (new_time_left < cache_time_left) {
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/*
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* Someone wants to shorten the timeout. Let it happen.
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*/
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return;
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}
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/*
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* By how much does the new timeout extend the remaining cache time?
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*/
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additional_time = new_time_left - cache_time_left;
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if (additional_time * 10 < 0) {
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/*
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* Integer overflow. We extend by so much that we have to write it.
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*/
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return;
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}
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/*
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* The comparison below is essentially equivalent to
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*
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* new_time_left > cache_time_left * 1.10
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*
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* but without floating point calculations.
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*/
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if (additional_time * 10 > cache_time_left) {
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/*
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* We extend the cache timeout by more than 10%. Do it.
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*/
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return;
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}
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/*
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* Now the more expensive data compare.
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*/
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if (data_blob_cmp(state->data, &data) != 0) {
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/*
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* Write a new value. Certainly do it.
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*/
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return;
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}
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/*
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* Extending the timeout by less than 10% for the same cache value is
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* not worth the trouble writing a value into gencache under a
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* possibly expensive transaction.
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*/
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state->gotit = true;
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}
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static bool gencache_have_val(const char *keystr, const DATA_BLOB *data,
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time_t timeout)
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{
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struct gencache_have_val_state state;
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state.new_timeout = timeout;
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state.data = data;
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state.gotit = false;
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if (!gencache_parse(keystr, gencache_have_val_parser, &state)) {
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return false;
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}
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return state.gotit;
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}
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static int last_stabilize_parser(TDB_DATA key, TDB_DATA data,
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void *private_data)
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{
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time_t *last_stabilize = private_data;
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if ((data.dsize != 0) && (data.dptr[data.dsize-1] == '\0')) {
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*last_stabilize = atoi((char *)data.dptr);
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}
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return 0;
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}
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/**
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* Set an entry in the cache file. If there's no such
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* one, then add it.
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*
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* @param keystr string that represents a key of this entry
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* @param blob DATA_BLOB value being cached
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* @param timeout time when the value is expired
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*
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* @retval true when entry is successfully stored
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* @retval false on failure
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**/
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bool gencache_set_data_blob(const char *keystr, const DATA_BLOB *blob,
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time_t timeout)
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{
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int ret;
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fstring hdr;
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int hdr_len;
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char* val;
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time_t last_stabilize;
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static int writecount;
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if (tdb_data_cmp(string_term_tdb_data(keystr),
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last_stabilize_key()) == 0) {
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DEBUG(10, ("Can't store %s as a key\n", keystr));
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return false;
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}
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if ((keystr == NULL) || (blob == NULL)) {
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return false;
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}
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if (!gencache_init()) {
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return false;
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}
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if ((timeout != 0) && gencache_have_val(keystr, blob, timeout)) {
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DEBUG(10, ("Did not store value for %s, we already got it\n",
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keystr));
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return true;
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}
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hdr_len = fstr_sprintf(hdr, CACHE_DATA_FMT, (int)timeout);
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if (hdr_len == -1) {
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return false;
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}
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if ((blob->length + (size_t)hdr_len) < blob->length) {
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return false;
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}
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val = talloc_array(talloc_tos(), char, hdr_len + blob->length);
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if (val == NULL) {
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return false;
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}
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memcpy(val, hdr, hdr_len);
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memcpy(val+hdr_len, blob->data, blob->length);
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DEBUG(10, ("Adding cache entry with key=[%s] and timeout="
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"[%s] (%d seconds %s)\n", keystr,
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timestring(talloc_tos(), timeout),
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(int)(timeout - time(NULL)),
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timeout > time(NULL) ? "ahead" : "in the past"));
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ret = tdb_store_bystring(
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cache_notrans->tdb, keystr,
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make_tdb_data((uint8_t *)val, talloc_array_length(val)),
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0);
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TALLOC_FREE(val);
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if (ret != 0) {
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return false;
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}
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/*
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* Every 100 writes within a single process, stabilize the cache with
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* a transaction. This is done to prevent a single transaction to
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* become huge and chew lots of memory.
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*/
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writecount += 1;
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if (writecount > lp_parm_int(-1, "gencache", "stabilize_count", 100)) {
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gencache_stabilize();
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writecount = 0;
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goto done;
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}
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/*
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* Every 5 minutes, call gencache_stabilize() to not let grow
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* gencache_notrans.tdb too large.
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*/
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last_stabilize = 0;
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tdb_parse_record(cache_notrans->tdb, last_stabilize_key(),
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last_stabilize_parser, &last_stabilize);
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if ((last_stabilize
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+ lp_parm_int(-1, "gencache", "stabilize_interval", 300))
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< time(NULL)) {
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gencache_stabilize();
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}
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done:
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return ret == 0;
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}
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static void gencache_del_parser(time_t timeout, DATA_BLOB blob,
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void *private_data)
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{
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if (timeout != 0) {
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bool *exists = private_data;
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*exists = true;
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}
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}
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/**
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* Delete one entry from the cache file.
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*
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* @param keystr string that represents a key of this entry
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*
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* @retval true upon successful deletion
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* @retval false in case of failure
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**/
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bool gencache_del(const char *keystr)
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{
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TDB_DATA key = string_term_tdb_data(keystr);
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bool exists = false;
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bool result = false;
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int ret;
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if (keystr == NULL) {
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return false;
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}
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if (!gencache_init()) {
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return false;
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}
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DEBUG(10, ("Deleting cache entry (key=[%s])\n", keystr));
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ret = tdb_chainlock(cache_notrans->tdb, key);
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if (ret == -1) {
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return false;
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}
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gencache_parse(keystr, gencache_del_parser, &exists);
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if (exists) {
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/*
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* We delete an element by setting its timeout to
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* 0. This way we don't have to do a transaction on
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* gencache.tdb every time we delete an element.
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*/
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result = gencache_set(keystr, "", 0);
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}
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tdb_chainunlock(cache_notrans->tdb, key);
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return result;
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}
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static bool gencache_pull_timeout(uint8_t *val, time_t *pres, char **payload)
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{
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time_t res;
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char *endptr;
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if (val == NULL) {
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return false;
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}
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res = strtol((char *)val, &endptr, 10);
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if ((endptr == NULL) || (*endptr != '/')) {
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DEBUG(2, ("Invalid gencache data format: %s\n", (char *)val));
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return false;
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}
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if (pres != NULL) {
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*pres = res;
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}
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if (payload != NULL) {
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*payload = endptr+1;
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}
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return true;
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}
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struct gencache_parse_state {
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void (*parser)(time_t timeout, DATA_BLOB blob, void *private_data);
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void *private_data;
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bool copy_to_notrans;
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};
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static int gencache_parse_fn(TDB_DATA key, TDB_DATA data, void *private_data)
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{
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struct gencache_parse_state *state;
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DATA_BLOB blob;
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time_t t;
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char *payload;
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bool ret;
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if (data.dptr == NULL) {
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return -1;
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}
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ret = gencache_pull_timeout(data.dptr, &t, &payload);
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if (!ret) {
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return -1;
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}
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state = (struct gencache_parse_state *)private_data;
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blob = data_blob_const(
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payload, data.dsize - PTR_DIFF(payload, data.dptr));
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state->parser(t, blob, state->private_data);
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if (state->copy_to_notrans) {
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tdb_store(cache_notrans->tdb, key, data, 0);
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}
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return 0;
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}
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bool gencache_parse(const char *keystr,
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void (*parser)(time_t timeout, DATA_BLOB blob,
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void *private_data),
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void *private_data)
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{
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struct gencache_parse_state state;
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TDB_DATA key = string_term_tdb_data(keystr);
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int ret;
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if (keystr == NULL) {
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return false;
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}
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if (tdb_data_cmp(key, last_stabilize_key()) == 0) {
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return false;
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}
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if (!gencache_init()) {
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return false;
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}
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state.parser = parser;
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state.private_data = private_data;
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state.copy_to_notrans = false;
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ret = tdb_chainlock(cache_notrans->tdb, key);
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if (ret != 0) {
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return false;
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}
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ret = tdb_parse_record(cache_notrans->tdb, key,
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gencache_parse_fn, &state);
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if (ret == 0) {
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tdb_chainunlock(cache_notrans->tdb, key);
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return true;
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}
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state.copy_to_notrans = true;
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ret = tdb_parse_record(cache->tdb, key, gencache_parse_fn, &state);
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if ((ret == -1) && (tdb_error(cache->tdb) == TDB_ERR_NOEXIST)) {
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/*
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* The record does not exist. Set a delete-marker in
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* gencache_notrans, so that we don't have to look at
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* the fcntl-based cache again.
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*/
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gencache_set(keystr, "", 0);
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}
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tdb_chainunlock(cache_notrans->tdb, key);
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return (ret == 0);
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}
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struct gencache_get_data_blob_state {
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TALLOC_CTX *mem_ctx;
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DATA_BLOB *blob;
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time_t timeout;
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bool result;
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};
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static void gencache_get_data_blob_parser(time_t timeout, DATA_BLOB blob,
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void *private_data)
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{
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struct gencache_get_data_blob_state *state =
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(struct gencache_get_data_blob_state *)private_data;
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if (timeout == 0) {
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state->result = false;
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return;
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}
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state->timeout = timeout;
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if (state->blob == NULL) {
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state->result = true;
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return;
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}
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*state->blob = data_blob_talloc(state->mem_ctx, blob.data,
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blob.length);
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if (state->blob->data == NULL) {
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state->result = false;
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return;
|
|
}
|
|
state->result = true;
|
|
}
|
|
|
|
/**
|
|
* Get existing entry from the cache file.
|
|
*
|
|
* @param keystr string that represents a key of this entry
|
|
* @param blob DATA_BLOB that is filled with entry's blob
|
|
* @param timeout pointer to a time_t that is filled with entry's
|
|
* timeout
|
|
*
|
|
* @retval true when entry is successfuly fetched
|
|
* @retval false for failure
|
|
**/
|
|
|
|
bool gencache_get_data_blob(const char *keystr, TALLOC_CTX *mem_ctx,
|
|
DATA_BLOB *blob,
|
|
time_t *timeout, bool *was_expired)
|
|
{
|
|
struct gencache_get_data_blob_state state;
|
|
bool expired = false;
|
|
|
|
state.result = false;
|
|
state.mem_ctx = mem_ctx;
|
|
state.blob = blob;
|
|
|
|
if (!gencache_parse(keystr, gencache_get_data_blob_parser, &state)) {
|
|
goto fail;
|
|
}
|
|
if (!state.result) {
|
|
goto fail;
|
|
}
|
|
if (state.timeout <= time(NULL)) {
|
|
/*
|
|
* We're expired, delete the entry. We can't use gencache_del
|
|
* here, because that uses gencache_get_data_blob for checking
|
|
* the existence of a record. We know the thing exists and
|
|
* directly store an empty value with 0 timeout.
|
|
*/
|
|
gencache_set(keystr, "", 0);
|
|
expired = true;
|
|
goto fail;
|
|
}
|
|
if (timeout) {
|
|
*timeout = state.timeout;
|
|
}
|
|
|
|
return true;
|
|
|
|
fail:
|
|
if (was_expired != NULL) {
|
|
*was_expired = expired;
|
|
}
|
|
if (state.result && state.blob) {
|
|
data_blob_free(state.blob);
|
|
}
|
|
return false;
|
|
}
|
|
|
|
struct stabilize_state {
|
|
bool written;
|
|
};
|
|
static int stabilize_fn(struct tdb_context *tdb, TDB_DATA key, TDB_DATA val,
|
|
void *priv);
|
|
|
|
static int wipe_fn(struct tdb_context *tdb, TDB_DATA key, TDB_DATA val,
|
|
void *priv);
|
|
|
|
/**
|
|
* Stabilize gencache
|
|
*
|
|
* Migrate the clear-if-first gencache data to the stable,
|
|
* transaction-based gencache.tdb
|
|
*/
|
|
|
|
bool gencache_stabilize(void)
|
|
{
|
|
struct stabilize_state state;
|
|
int res;
|
|
char *now;
|
|
|
|
if (!gencache_init()) {
|
|
return false;
|
|
}
|
|
|
|
res = tdb_transaction_start_nonblock(cache->tdb);
|
|
if (res != 0) {
|
|
if (tdb_error(cache->tdb) == TDB_ERR_NOLOCK)
|
|
{
|
|
/*
|
|
* Someone else already does the stabilize,
|
|
* this does not have to be done twice
|
|
*/
|
|
return true;
|
|
}
|
|
|
|
DEBUG(10, ("Could not start transaction on gencache.tdb: "
|
|
"%s\n", tdb_errorstr(cache->tdb)));
|
|
return false;
|
|
}
|
|
|
|
res = tdb_lockall(cache_notrans->tdb);
|
|
if (res != 0) {
|
|
tdb_transaction_cancel(cache->tdb);
|
|
DEBUG(10, ("Could not get allrecord lock on "
|
|
"gencache_notrans.tdb: %s\n",
|
|
tdb_errorstr(cache_notrans->tdb)));
|
|
return false;
|
|
}
|
|
|
|
state.written = false;
|
|
|
|
res = tdb_traverse(cache_notrans->tdb, stabilize_fn, &state);
|
|
if (res < 0) {
|
|
tdb_unlockall(cache_notrans->tdb);
|
|
tdb_transaction_cancel(cache->tdb);
|
|
return false;
|
|
}
|
|
|
|
if (!state.written) {
|
|
tdb_unlockall(cache_notrans->tdb);
|
|
tdb_transaction_cancel(cache->tdb);
|
|
return true;
|
|
}
|
|
|
|
res = tdb_transaction_commit(cache->tdb);
|
|
if (res != 0) {
|
|
DEBUG(10, ("tdb_transaction_commit on gencache.tdb failed: "
|
|
"%s\n", tdb_errorstr(cache->tdb)));
|
|
tdb_unlockall(cache_notrans->tdb);
|
|
return false;
|
|
}
|
|
|
|
res = tdb_traverse(cache_notrans->tdb, wipe_fn, NULL);
|
|
if (res < 0) {
|
|
DEBUG(10, ("tdb_traverse with wipe_fn on gencache_notrans.tdb "
|
|
"failed: %s\n",
|
|
tdb_errorstr(cache_notrans->tdb)));
|
|
tdb_unlockall(cache_notrans->tdb);
|
|
return false;
|
|
}
|
|
|
|
res = tdb_unlockall(cache_notrans->tdb);
|
|
if (res != 0) {
|
|
DEBUG(10, ("tdb_unlockall on gencache.tdb failed: "
|
|
"%s\n", tdb_errorstr(cache->tdb)));
|
|
return false;
|
|
}
|
|
|
|
now = talloc_asprintf(talloc_tos(), "%d", (int)time(NULL));
|
|
if (now != NULL) {
|
|
tdb_store(cache_notrans->tdb, last_stabilize_key(),
|
|
string_term_tdb_data(now), 0);
|
|
TALLOC_FREE(now);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
static int stabilize_fn(struct tdb_context *tdb, TDB_DATA key, TDB_DATA val,
|
|
void *priv)
|
|
{
|
|
struct stabilize_state *state = (struct stabilize_state *)priv;
|
|
int res;
|
|
time_t timeout;
|
|
|
|
if (tdb_data_cmp(key, last_stabilize_key()) == 0) {
|
|
return 0;
|
|
}
|
|
|
|
if (!gencache_pull_timeout(val.dptr, &timeout, NULL)) {
|
|
DEBUG(10, ("Ignoring invalid entry\n"));
|
|
return 0;
|
|
}
|
|
if ((timeout < time(NULL)) || (val.dsize == 0)) {
|
|
res = tdb_delete(cache->tdb, key);
|
|
if (res == 0) {
|
|
state->written = true;
|
|
} else if (tdb_error(cache->tdb) == TDB_ERR_NOEXIST) {
|
|
res = 0;
|
|
}
|
|
} else {
|
|
res = tdb_store(cache->tdb, key, val, 0);
|
|
if (res == 0) {
|
|
state->written = true;
|
|
}
|
|
}
|
|
|
|
if (res != 0) {
|
|
DEBUG(10, ("Transfer to gencache.tdb failed: %s\n",
|
|
tdb_errorstr(cache->tdb)));
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int wipe_fn(struct tdb_context *tdb, TDB_DATA key, TDB_DATA val,
|
|
void *priv)
|
|
{
|
|
int res;
|
|
bool ok;
|
|
time_t timeout;
|
|
|
|
res = tdb_data_cmp(key, last_stabilize_key());
|
|
if (res == 0) {
|
|
return 0;
|
|
}
|
|
|
|
ok = gencache_pull_timeout(val.dptr, &timeout, NULL);
|
|
if (!ok) {
|
|
DEBUG(10, ("Ignoring invalid entry\n"));
|
|
return 0;
|
|
}
|
|
|
|
res = tdb_delete(tdb, key);
|
|
if (res != 0) {
|
|
DEBUG(10, ("tdb_delete from gencache_notrans.tdb failed: "
|
|
"%s\n", tdb_errorstr(cache_notrans->tdb)));
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* Get existing entry from the cache file.
|
|
*
|
|
* @param keystr string that represents a key of this entry
|
|
* @param valstr buffer that is allocated and filled with the entry value
|
|
* buffer's disposing must be done outside
|
|
* @param timeout pointer to a time_t that is filled with entry's
|
|
* timeout
|
|
*
|
|
* @retval true when entry is successfully fetched
|
|
* @retval false for failure
|
|
**/
|
|
|
|
bool gencache_get(const char *keystr, TALLOC_CTX *mem_ctx, char **value,
|
|
time_t *ptimeout)
|
|
{
|
|
DATA_BLOB blob;
|
|
bool ret = false;
|
|
|
|
ret = gencache_get_data_blob(keystr, mem_ctx, &blob, ptimeout, NULL);
|
|
if (!ret) {
|
|
return false;
|
|
}
|
|
if ((blob.data == NULL) || (blob.length == 0)) {
|
|
data_blob_free(&blob);
|
|
return false;
|
|
}
|
|
if (blob.data[blob.length-1] != '\0') {
|
|
/* Not NULL terminated, can't be a string */
|
|
data_blob_free(&blob);
|
|
return false;
|
|
}
|
|
if (value) {
|
|
/*
|
|
* talloc_move generates a type-punned warning here. As we
|
|
* leave the function immediately, do a simple talloc_steal.
|
|
*/
|
|
*value = (char *)talloc_steal(mem_ctx, blob.data);
|
|
return true;
|
|
}
|
|
data_blob_free(&blob);
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Set an entry in the cache file. If there's no such
|
|
* one, then add it.
|
|
*
|
|
* @param keystr string that represents a key of this entry
|
|
* @param value text representation value being cached
|
|
* @param timeout time when the value is expired
|
|
*
|
|
* @retval true when entry is successfuly stored
|
|
* @retval false on failure
|
|
**/
|
|
|
|
bool gencache_set(const char *keystr, const char *value, time_t timeout)
|
|
{
|
|
DATA_BLOB blob = data_blob_const(value, strlen(value)+1);
|
|
return gencache_set_data_blob(keystr, &blob, timeout);
|
|
}
|
|
|
|
struct gencache_iterate_blobs_state {
|
|
void (*fn)(const char *key, DATA_BLOB value,
|
|
time_t timeout, void *private_data);
|
|
const char *pattern;
|
|
void *private_data;
|
|
bool in_persistent;
|
|
};
|
|
|
|
static int gencache_iterate_blobs_fn(struct tdb_context *tdb, TDB_DATA key,
|
|
TDB_DATA data, void *priv)
|
|
{
|
|
struct gencache_iterate_blobs_state *state =
|
|
(struct gencache_iterate_blobs_state *)priv;
|
|
char *keystr;
|
|
char *free_key = NULL;
|
|
time_t timeout;
|
|
char *payload;
|
|
|
|
if (tdb_data_cmp(key, last_stabilize_key()) == 0) {
|
|
return 0;
|
|
}
|
|
if (state->in_persistent && tdb_exists(cache_notrans->tdb, key)) {
|
|
return 0;
|
|
}
|
|
|
|
if (key.dptr[key.dsize-1] == '\0') {
|
|
keystr = (char *)key.dptr;
|
|
} else {
|
|
/* ensure 0-termination */
|
|
keystr = talloc_strndup(talloc_tos(), (char *)key.dptr, key.dsize);
|
|
free_key = keystr;
|
|
if (keystr == NULL) {
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
if (!gencache_pull_timeout(data.dptr, &timeout, &payload)) {
|
|
goto done;
|
|
}
|
|
|
|
if (timeout == 0) {
|
|
/* delete marker */
|
|
goto done;
|
|
}
|
|
|
|
if (fnmatch(state->pattern, keystr, 0) != 0) {
|
|
goto done;
|
|
}
|
|
|
|
DEBUG(10, ("Calling function with arguments "
|
|
"(key=[%s], timeout=[%s])\n",
|
|
keystr, timestring(talloc_tos(), timeout)));
|
|
|
|
state->fn(keystr,
|
|
data_blob_const(payload,
|
|
data.dsize - PTR_DIFF(payload, data.dptr)),
|
|
timeout, state->private_data);
|
|
|
|
done:
|
|
TALLOC_FREE(free_key);
|
|
return 0;
|
|
}
|
|
|
|
void gencache_iterate_blobs(void (*fn)(const char *key, DATA_BLOB value,
|
|
time_t timeout, void *private_data),
|
|
void *private_data, const char *pattern)
|
|
{
|
|
struct gencache_iterate_blobs_state state;
|
|
|
|
if ((fn == NULL) || (pattern == NULL) || !gencache_init()) {
|
|
return;
|
|
}
|
|
|
|
DEBUG(5, ("Searching cache keys with pattern %s\n", pattern));
|
|
|
|
state.fn = fn;
|
|
state.pattern = pattern;
|
|
state.private_data = private_data;
|
|
|
|
state.in_persistent = false;
|
|
tdb_traverse(cache_notrans->tdb, gencache_iterate_blobs_fn, &state);
|
|
|
|
state.in_persistent = true;
|
|
tdb_traverse(cache->tdb, gencache_iterate_blobs_fn, &state);
|
|
}
|
|
|
|
/**
|
|
* Iterate through all entries which key matches to specified pattern
|
|
*
|
|
* @param fn pointer to the function that will be supplied with each single
|
|
* matching cache entry (key, value and timeout) as an arguments
|
|
* @param data void pointer to an arbitrary data that is passed directly to the fn
|
|
* function on each call
|
|
* @param keystr_pattern pattern the existing entries' keys are matched to
|
|
*
|
|
**/
|
|
|
|
struct gencache_iterate_state {
|
|
void (*fn)(const char *key, const char *value, time_t timeout,
|
|
void *priv);
|
|
void *private_data;
|
|
};
|
|
|
|
static void gencache_iterate_fn(const char *key, DATA_BLOB value,
|
|
time_t timeout, void *private_data)
|
|
{
|
|
struct gencache_iterate_state *state =
|
|
(struct gencache_iterate_state *)private_data;
|
|
char *valstr;
|
|
char *free_val = NULL;
|
|
|
|
if (value.data[value.length-1] == '\0') {
|
|
valstr = (char *)value.data;
|
|
} else {
|
|
/* ensure 0-termination */
|
|
valstr = talloc_strndup(talloc_tos(), (char *)value.data, value.length);
|
|
free_val = valstr;
|
|
if (valstr == NULL) {
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
DEBUG(10, ("Calling function with arguments "
|
|
"(key=[%s], value=[%s], timeout=[%s])\n",
|
|
key, valstr, timestring(talloc_tos(), timeout)));
|
|
|
|
state->fn(key, valstr, timeout, state->private_data);
|
|
|
|
done:
|
|
|
|
TALLOC_FREE(free_val);
|
|
}
|
|
|
|
void gencache_iterate(void (*fn)(const char *key, const char *value,
|
|
time_t timeout, void *dptr),
|
|
void *private_data, const char *pattern)
|
|
{
|
|
struct gencache_iterate_state state;
|
|
|
|
if (fn == NULL) {
|
|
return;
|
|
}
|
|
state.fn = fn;
|
|
state.private_data = private_data;
|
|
gencache_iterate_blobs(gencache_iterate_fn, &state, pattern);
|
|
}
|