lib/gencache.c

Generic, persistent and shared between processes cache mechanism for use by various parts of the Samba code [詳細]

ソースコードを見る。

関数
BOOL	gencache_init (void)
	Cache initialisation function.
BOOL	gencache_shutdown (void)
	Cache shutdown function.
BOOL	gencache_set (const char *keystr, const char *value, time_t timeout)
	Set an entry in the cache file.
BOOL	gencache_del (const char *keystr)
	Delete one entry from the cache file.
BOOL	gencache_get (const char *keystr, char **valstr, time_t *timeout)
	Get existing entry from the cache file.
void	gencache_iterate (void(*fn)(const char *key, const char *value, time_t timeout, void *dptr), void *data, const char *keystr_pattern)
	Iterate through all entries which key matches to specified pattern
int	gencache_lock_entry (const char *key)
void	gencache_unlock_entry (const char *key)
変数
static TDB_CONTEXT *	cache
static BOOL	cache_readonly

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説明

Generic, persistent and shared between processes cache mechanism for use by various parts of the Samba code

gencache.c で定義されています。

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関数

BOOL gencache_init

(

void

)

Cache initialisation function.

Opens cache tdb file or creates it if does not exist.

戻り値:

true on successful initialisation of the cache or false on failure

gencache.c の 52 行で定義されています。

参照先 cache・cache_readonly・errno・lock_path()・tdb_open_log().

参照元 gencache_del()・gencache_get()・gencache_iterate()・gencache_lock_entry()・gencache_set()・gencache_unlock_entry()・namecache_delete()・namecache_enable()・namecache_fetch()・namecache_flush()・namecache_status_fetch()・namecache_status_store()・namecache_store()・run_local_gencache()・saf_delete()・saf_fetch()・saf_store()・sitename_fetch()・sitename_store()・trustdom_cache_enable()・trustdom_cache_fetch()・trustdom_cache_fetch_timestamp()・trustdom_cache_flush()・trustdom_cache_store()・trustdom_cache_store_timestamp().

{
        char* cache_fname = NULL;
        
        /* skip file open if it's already opened */
        if (cache) return True;

        cache_fname = lock_path("gencache.tdb");

        DEBUG(5, ("Opening cache file at %s\n", cache_fname));

        cache = tdb_open_log(cache_fname, 0, TDB_DEFAULT,
                             O_RDWR|O_CREAT, 0644);

        if (!cache && (errno == EACCES)) {
                cache = tdb_open_log(cache_fname, 0, TDB_DEFAULT, O_RDONLY, 0644);
                if (cache) {
                        cache_readonly = True;
                        DEBUG(5, ("gencache_init: Opening cache file %s read-only.\n", cache_fname));
                }
        }

        if (!cache) {
                DEBUG(5, ("Attempt to open gencache.tdb has failed.\n"));
                return False;
        }
        return True;
}

BOOL gencache_shutdown

(

void

)

Cache shutdown function.

Closes opened cache tdb file.

戻り値:

true on successful closing the cache or false on failure during cache shutdown

gencache.c の 89 行で定義されています。

参照先 cache・cache_readonly・tdb_close().

参照元 namecache_shutdown()・net_cache_add()・net_cache_flush()・net_cache_list()・run_local_gencache()・trustdom_cache_shutdown().

{
        int ret;
        /* tdb_close routine returns -1 on error */
        if (!cache) return False;
        DEBUG(5, ("Closing cache file\n"));
        ret = tdb_close(cache);
        cache = NULL;
        cache_readonly = False;
        return ret != -1;
}

BOOL gencache_set	(	const char *	keystr,
		const char *	value,
		time_t	timeout
	)

Set an entry in the cache file.

If there's no such one, then add it.

引数:

	keystr	string that represents a key of this entry
	value	text representation value being cached
	timeout	time when the value is expired

戻り値:

	true	when entry is successfuly stored
	false	on failure

gencache.c の 114 行で定義されています。

参照先 asprintf()・cache・cache_readonly・TDB_DATA::dptr・TDB_DATA::dsize・gencache_init()・tdb_store().

参照元 cache_account_policy_set()・namecache_status_store()・namecache_store()・net_cache_add()・run_local_gencache()・saf_store()・sitename_store()・trustdom_cache_store()・trustdom_cache_store_timestamp()・wins_srv_died().

{
        int ret;
        TDB_DATA keybuf, databuf;
        char* valstr = NULL;
        
        /* fail completely if get null pointers passed */
        SMB_ASSERT(keystr && value);

        if (!gencache_init()) return False;
        
        if (cache_readonly) {
                return False;
        }

        asprintf(&valstr, CACHE_DATA_FMT, (int)timeout, value);
        if (!valstr)
                return False;

        keybuf.dptr = CONST_DISCARD(char *, keystr);
        keybuf.dsize = strlen(keystr)+1;
        databuf.dptr = valstr;
        databuf.dsize = strlen(valstr)+1;
        DEBUG(10, ("Adding cache entry with key = %s; value = %s and timeout ="
                   " %s (%d seconds %s)\n", keybuf.dptr, value,ctime(&timeout),
                   (int)(timeout - time(NULL)), 
                   timeout > time(NULL) ? "ahead" : "in the past"));

        ret = tdb_store(cache, keybuf, databuf, 0);
        SAFE_FREE(valstr);
        
        return ret == 0;
}

BOOL gencache_del

(

const char *

keystr

)

Delete one entry from the cache file.

引数:

keystr

string that represents a key of this entry

戻り値:

	true	upon successful deletion
	false	in case of failure

gencache.c の 157 行で定義されています。

参照先 cache・cache_readonly・TDB_DATA::dptr・TDB_DATA::dsize・gencache_init()・tdb_delete().

参照元 delete_cache_entry()・flush_netbios_name()・flush_trustdom_name()・namecache_delete()・net_cache_del()・run_local_gencache()・saf_delete()・sitename_store()・wins_srv_alive().

{
        int ret;
        TDB_DATA keybuf;
        
        /* fail completely if get null pointers passed */
        SMB_ASSERT(keystr);

        if (!gencache_init()) return False;     
        
        if (cache_readonly) {
                return False;
        }

        keybuf.dptr = CONST_DISCARD(char *, keystr);
        keybuf.dsize = strlen(keystr)+1;
        DEBUG(10, ("Deleting cache entry (key = %s)\n", keystr));
        ret = tdb_delete(cache, keybuf);
        
        return ret == 0;
}

BOOL gencache_get	(	const char *	keystr,
		char **	valstr,
		time_t *	timeout
	)

Get existing entry from the cache file.

引数:

	keystr	string that represents a key of this entry
	valstr	buffer that is allocated and filled with the entry value buffer's disposing must be done outside
	timeout	pointer to a time_t that is filled with entry's timeout

戻り値:

	true	when entry is successfuly fetched
	False	for failure

gencache.c の 193 行で定義されています。

参照先 cache・TDB_DATA::dptr・TDB_DATA::dsize・gencache_init()・t・tdb_delete()・tdb_fetch().

参照元 cache_account_policy_get()・namecache_fetch()・namecache_status_fetch()・net_cache_get()・run_local_gencache()・saf_fetch()・sitename_fetch()・trustdom_cache_fetch()・trustdom_cache_fetch_timestamp()・wins_srv_is_dead().

{
        TDB_DATA keybuf, databuf;
        time_t t;
        char *endptr;

        /* fail completely if get null pointers passed */
        SMB_ASSERT(keystr);

        if (!gencache_init()) {
                return False;
        }
        
        keybuf.dptr = CONST_DISCARD(char *, keystr);
        keybuf.dsize = strlen(keystr)+1;
        databuf = tdb_fetch(cache, keybuf);

        if (databuf.dptr == NULL) {
                DEBUG(10, ("Cache entry with key = %s couldn't be found\n",
                           keystr));
                return False;
        }

        t = strtol(databuf.dptr, &endptr, 10);

        if ((endptr == NULL) || (*endptr != '/')) {
                DEBUG(2, ("Invalid gencache data format: %s\n", databuf.dptr));
                SAFE_FREE(databuf.dptr);
                return False;
        }

        DEBUG(10, ("Returning %s cache entry: key = %s, value = %s, "
                   "timeout = %s", t > time(NULL) ? "valid" :
                   "expired", keystr, endptr+1, ctime(&t)));

        if (t <= time(NULL)) {

                /* We're expired, delete the entry */
                tdb_delete(cache, keybuf);

                SAFE_FREE(databuf.dptr);
                return False;
        }

        if (valstr) {
                *valstr = SMB_STRDUP(endptr+1);
                if (*valstr == NULL) {
                        SAFE_FREE(databuf.dptr);
                        DEBUG(0, ("strdup failed\n"));
                        return False;
                }
        }
        
        SAFE_FREE(databuf.dptr);

        if (timeout) {
                *timeout = t;
        }

        return True;
} 

void gencache_iterate	(	void(*)(const char *key, const char *value, time_t timeout, void *dptr)	fn,
		void *	data,
		const char *	keystr_pattern
	)

Iterate through all entries which key matches to specified pattern

引数:

	fn	pointer to the function that will be supplied with each single matching cache entry (key, value and timeout) as an arguments
	data	void pointer to an arbitrary data that is passed directly to the fn function on each call
	keystr_pattern	pattern the existing entries' keys are matched to

gencache.c の 267 行で定義されています。

参照先 asprintf()・cache・TDB_DATA::dptr・TDB_DATA::dsize・fn・gencache_init()・keys_node::next・keys_node::node_key・status・tdb_fetch()・tdb_search_keys()・tdb_search_list_free().

参照元 namecache_flush()・net_cache_flush()・net_cache_list()・net_cache_search()・trustdom_cache_flush().

{
        TDB_LIST_NODE *node, *first_node;
        TDB_DATA databuf;
        char *keystr = NULL, *valstr = NULL, *entry = NULL;
        time_t timeout = 0;
        int status;
        unsigned u;

        /* fail completely if get null pointers passed */
        SMB_ASSERT(fn && keystr_pattern);

        if (!gencache_init()) return;

        DEBUG(5, ("Searching cache keys with pattern %s\n", keystr_pattern));
        node = tdb_search_keys(cache, keystr_pattern);
        first_node = node;
        
        while (node) {
                char *fmt;

                /* ensure null termination of the key string */
                keystr = SMB_STRNDUP(node->node_key.dptr, node->node_key.dsize);
                if (!keystr) {
                        break;
                }
                
                /* 
                 * We don't use gencache_get function, because we need to iterate through
                 * all of the entries. Validity verification is up to fn routine.
                 */
                databuf = tdb_fetch(cache, node->node_key);
                if (!databuf.dptr || databuf.dsize <= TIMEOUT_LEN) {
                        SAFE_FREE(databuf.dptr);
                        SAFE_FREE(keystr);
                        node = node->next;
                        continue;
                }
                entry = SMB_STRNDUP(databuf.dptr, databuf.dsize);
                if (!entry) {
                        SAFE_FREE(databuf.dptr);
                        SAFE_FREE(keystr);
                        break;
                }

                SAFE_FREE(databuf.dptr);

                valstr = (char *)SMB_MALLOC(databuf.dsize + 1 - TIMEOUT_LEN);
                if (!valstr) {
                        SAFE_FREE(entry);
                        SAFE_FREE(keystr);
                        break;
                }

                asprintf(&fmt, READ_CACHE_DATA_FMT_TEMPLATE, (unsigned int)databuf.dsize - TIMEOUT_LEN);
                if (!fmt) {
                        SAFE_FREE(valstr);
                        SAFE_FREE(entry);
                        SAFE_FREE(keystr);
                        break;
                }
                status = sscanf(entry, fmt, &u, valstr);
                SAFE_FREE(fmt);

                if ( status != 2 ) {
                        DEBUG(0,("gencache_iterate: invalid return from sscanf %d\n",status));
                }
                timeout = u;
                
                DEBUG(10, ("Calling function with arguments (key = %s, value = %s, timeout = %s)\n",
                           keystr, valstr, ctime(&timeout)));
                fn(keystr, valstr, timeout, data);
                
                SAFE_FREE(valstr);
                SAFE_FREE(entry);
                SAFE_FREE(keystr);
                node = node->next;
        }
        
        tdb_search_list_free(first_node);
}

int gencache_lock_entry

(

const char *

key

)

gencache.c の 354 行で定義されています。

参照先 cache・gencache_init()・tdb_lock_bystring().

{
        if (!gencache_init())
                return -1;
        
        return tdb_lock_bystring(cache, key);
}

void gencache_unlock_entry

(

const char *

key

)

gencache.c の 366 行で定義されています。

参照先 cache・gencache_init()・tdb_unlock_bystring().

{
        if (!gencache_init())
                return;
        
        tdb_unlock_bystring(cache, key);
        return;
}

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変数

TDB_CONTEXT* cache [static]

gencache.c の 33 行で定義されています。

参照元 enum_dom_groups()・enum_local_groups()・gencache_del()・gencache_get()・gencache_init()・gencache_iterate()・gencache_lock_entry()・gencache_set()・gencache_shutdown()・gencache_unlock_entry()・idmap_cache_del()・idmap_cache_destructor()・idmap_cache_init()・idmap_cache_map_id()・idmap_cache_map_sid()・idmap_cache_set()・idmap_cache_set_negative_id()・idmap_cache_set_negative_sid()・idmap_cache_shutdown()・lockout_policy()・login_cache_delentry()・login_cache_init()・login_cache_read()・login_cache_shutdown()・login_cache_write()・lookup_cached_name()・lookup_cached_sid()・lookup_groupmem()・lookup_useraliases()・lookup_usergroups()・name_to_sid()・password_policy()・pcap_cache_destroy()・query_user()・query_user_list()・rids_to_names()・sid_to_name()・trusted_domains()・wcache_cached_creds_exist()・wcache_count_cached_creds()・wcache_get_creds()・wcache_invalidate_cache()・wcache_invalidate_samlogon()・wcache_remove_oldest_cached_creds().

BOOL cache_readonly [static]

gencache.c の 34 行で定義されています。

参照元 gencache_del()・gencache_init()・gencache_set()・gencache_shutdown().

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