| 1 | /* | 
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| 2 | Unix SMB/CIFS implementation. | 
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| 3 | In-memory cache | 
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| 4 | Copyright (C) Volker Lendecke 2007-2008 | 
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| 5 |  | 
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| 6 | This program is free software; you can redistribute it and/or modify | 
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| 7 | it under the terms of the GNU General Public License as published by | 
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| 8 | the Free Software Foundation; either version 3 of the License, or | 
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| 9 | (at your option) any later version. | 
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| 10 |  | 
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| 11 | This program is distributed in the hope that it will be useful, | 
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| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | 
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| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
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| 14 | GNU General Public License for more details. | 
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| 15 |  | 
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| 16 | You should have received a copy of the GNU General Public License | 
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| 17 | along with this program.  If not, see <http://www.gnu.org/licenses/>. | 
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| 18 | */ | 
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| 19 |  | 
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| 20 | #ifndef __MEMCACHE_H__ | 
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| 21 | #define __MEMCACHE_H__ | 
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| 22 |  | 
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| 23 | #include "includes.h" | 
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| 24 |  | 
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| 25 | struct memcache; | 
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| 26 |  | 
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| 27 | /* | 
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| 28 | * A memcache can store different subkeys with overlapping keys, the | 
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| 29 | * memcache_number becomes part of the key. Feel free to add caches of your | 
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| 30 | * own here. | 
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| 31 | * | 
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| 32 | * If you add talloc type caches, also note this in the switch statement in | 
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| 33 | * memcache_is_talloc(). | 
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| 34 | */ | 
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| 35 |  | 
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| 36 | enum memcache_number { | 
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| 37 | STAT_CACHE, | 
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| 38 | UID_SID_CACHE, | 
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| 39 | SID_UID_CACHE, | 
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| 40 | GID_SID_CACHE, | 
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| 41 | SID_GID_CACHE, | 
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| 42 | GETWD_CACHE, | 
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| 43 | GETPWNAM_CACHE,         /* talloc */ | 
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| 44 | MANGLE_HASH2_CACHE, | 
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| 45 | PDB_GETPWSID_CACHE,     /* talloc */ | 
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| 46 | SINGLETON_CACHE_TALLOC, /* talloc */ | 
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| 47 | SINGLETON_CACHE | 
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| 48 | }; | 
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| 49 |  | 
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| 50 | /* | 
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| 51 | * Create a memcache structure. max_size is in bytes, if you set it 0 it will | 
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| 52 | * not forget anything. | 
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| 53 | */ | 
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| 54 |  | 
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| 55 | struct memcache *memcache_init(TALLOC_CTX *mem_ctx, size_t max_size); | 
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| 56 |  | 
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| 57 | /* | 
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| 58 | * If you set this global memcache, use it as the default cache when NULL is | 
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| 59 | * passed to the memcache functions below. This is a workaround for many | 
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| 60 | * situations where passing the cache everywhere would be a big hassle. | 
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| 61 | */ | 
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| 62 |  | 
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| 63 | void memcache_set_global(struct memcache *cache); | 
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| 64 |  | 
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| 65 | /* | 
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| 66 | * Add a data blob to the cache | 
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| 67 | */ | 
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| 68 |  | 
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| 69 | void memcache_add(struct memcache *cache, enum memcache_number n, | 
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| 70 | DATA_BLOB key, DATA_BLOB value); | 
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| 71 |  | 
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| 72 | /* | 
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| 73 | * Add a talloc object to the cache. The difference to memcache_add() is that | 
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| 74 | * when the objects is to be discared, talloc_free is called for it. Also | 
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| 75 | * talloc_move() ownership of the object to the cache. | 
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| 76 | * | 
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| 77 | * Please note that the current implementation has a fixed relationship | 
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| 78 | * between what cache subtypes store talloc objects and which ones store plain | 
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| 79 | * blobs. We can fix this, but for now we don't have a mixed use of blobs vs | 
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| 80 | * talloc objects in the cache types. | 
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| 81 | */ | 
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| 82 |  | 
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| 83 | void memcache_add_talloc(struct memcache *cache, enum memcache_number n, | 
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| 84 | DATA_BLOB key, void *ptr); | 
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| 85 |  | 
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| 86 | /* | 
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| 87 | * Delete an object from the cache | 
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| 88 | */ | 
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| 89 |  | 
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| 90 | void memcache_delete(struct memcache *cache, enum memcache_number n, | 
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| 91 | DATA_BLOB key); | 
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| 92 |  | 
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| 93 | /* | 
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| 94 | * Look up an object from the cache. Memory still belongs to the cache, so | 
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| 95 | * make a copy of it if needed. | 
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| 96 | */ | 
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| 97 |  | 
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| 98 | bool memcache_lookup(struct memcache *cache, enum memcache_number n, | 
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| 99 | DATA_BLOB key, DATA_BLOB *value); | 
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| 100 |  | 
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| 101 | /* | 
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| 102 | * Look up an object from the cache. Memory still belongs to the cache, so | 
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| 103 | * make a copy of it if needed. | 
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| 104 | */ | 
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| 105 |  | 
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| 106 | void *memcache_lookup_talloc(struct memcache *cache, enum memcache_number n, | 
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| 107 | DATA_BLOB key); | 
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| 108 |  | 
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| 109 | /* | 
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| 110 | * Flush a complete cache subset. | 
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| 111 | */ | 
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| 112 |  | 
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| 113 | void memcache_flush(struct memcache *cache, enum memcache_number n); | 
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| 114 |  | 
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| 115 | #endif | 
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