3 * $Id: cnid_last.c,v 1.5 2010-03-31 09:47:32 franklahm Exp $
5 * Copyright (c) 1999. Adrian Sun (asun@zoology.washington.edu)
6 * All Rights Reserved. See COPYRIGHT.
12 #endif /* HAVE_CONFIG_H */
14 #ifdef CNID_BACKEND_LAST
16 #include "cnid_last.h"
17 #include <atalk/util.h>
18 #include <atalk/logger.h>
20 #include <sys/types.h>
23 #include <arpa/inet.h>
25 /* ------------------------ */
26 cnid_t cnid_last_add(struct _cnid_db *cdb, const struct stat *st,
27 cnid_t did _U_, const char *name _U_, size_t len _U_, cnid_t hint _U_)
30 /* FIXME: it relies on fact, that this is never called twice for the same file/dir. */
31 /* Propably we should look through DID tree. */
34 * First thing: DID and FNUMs are
35 * in the same space for purposes of enumerate (and several
36 * other wierd places). While we consider this Apple's bug,
37 * this is the work-around: In order to maintain constant and
38 * unique DIDs and FNUMs, we monotonically generate the DIDs
39 * during the session, and derive the FNUMs from the filesystem.
40 * Since the DIDs are small, we insure that the FNUMs are fairly
41 * large by setting thier high bits to the device number.
43 * AFS already does something very similar to this for the
44 * inode number, so we don't repeat the procedure.
47 * due to complaints over did's being non-persistent,
48 * here's the current hack to provide semi-persistent
50 * 1) we reserve the first bit for file ids.
51 * 2) the next 7 bits are for the device.
52 * 3) the remaining 24 bits are for the inode.
54 * both the inode and device information are actually hashes
55 * that are then truncated to the requisite bit length.
57 * it should be okay to use lstat to deal with symlinks.
60 struct _cnid_last_private *priv;
62 if (!cdb || !(cdb->_private))
65 priv = (struct _cnid_last_private *) (cdb->_private);
67 if (S_ISDIR(st->st_mode))
68 return htonl(priv->last_did++);
70 return htonl((st->st_dev << 16) | (st->st_ino & 0x0000ffff));
75 void cnid_last_close(struct _cnid_db *cdb)
84 int cnid_last_delete(struct _cnid_db *cdb _U_, const cnid_t id _U_)
90 /* Return CNID for a given did/name. */
91 cnid_t cnid_last_get(struct _cnid_db *cdb _U_, cnid_t did _U_, const char *name _U_, size_t len _U_)
93 /* FIXME: it relies on fact, that this is never called twice for the same file/dir. */
94 /* Propably we should look through DID tree. */
100 cnid_t cnid_last_lookup(struct _cnid_db *cdb _U_, const struct stat *st _U_, cnid_t did _U_,
101 const char *name _U_, size_t len _U_)
103 /* FIXME: this function doesn't work in [last] scheme ! */
104 /* Should be never called or CNID should be somewhat refactored again. */
109 static struct _cnid_db *cnid_last_new(const char *volpath)
111 struct _cnid_db *cdb;
112 struct _cnid_last_private *priv;
114 if ((cdb = (struct _cnid_db *) calloc(1, sizeof(struct _cnid_db))) == NULL)
117 if ((cdb->volpath = strdup(volpath)) == NULL) {
122 if ((cdb->_private = calloc(1, sizeof(struct _cnid_last_private))) == NULL) {
128 /* Set up private state */
129 priv = (struct _cnid_last_private *) (cdb->_private);
132 /* Set up standard fields */
134 cdb->cnid_add = cnid_last_add;
135 cdb->cnid_delete = cnid_last_delete;
136 cdb->cnid_get = cnid_last_get;
137 cdb->cnid_lookup = cnid_last_lookup;
138 cdb->cnid_nextid = NULL; /* cnid_last_nextid; */
139 cdb->cnid_resolve = cnid_last_resolve;
140 cdb->cnid_update = cnid_last_update;
141 cdb->cnid_close = cnid_last_close;
146 struct _cnid_db *cnid_last_open(struct cnid_open_args *args)
148 struct _cnid_db *cdb;
154 if ((cdb = cnid_last_new(args->dir)) == NULL) {
155 LOG(log_error, logtype_default, "cnid_open: Unable to allocate memory for database");
162 struct _cnid_module cnid_last_module = {
169 /* Return the did/name pair corresponding to a CNID. */
170 char *cnid_last_resolve(struct _cnid_db *cdb _U_, cnid_t * id _U_, void *buffer _U_, size_t len _U_)
172 /* FIXME: frankly, it does not work. As get, add and other functions. */
177 int cnid_last_update(struct _cnid_db *cdb _U_, cnid_t id _U_, const struct stat *st _U_,
178 cnid_t did _U_, const char *name _U_, size_t len _U_)
184 #endif /* CNID_BACKEND_LAST */