cnid.h

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/*
 * Copyright (c) 2003 the Netatalk Team
 * Copyright (c) 2003 Rafal Lewczuk <rlewczuk@pronet.pl>
 * Copyright (c) 2010 Frank Lahm
 *
 * This program is free software; you can redistribute and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation version 2 of the License or later
 * version if explicitly stated by any of above copyright holders.
 *
 * 2024/07/05: Rafal Lewczuk gave permission to change the license
 * to a later verion of the GNU GPL in
 * https://github.com/Netatalk/netatalk/issues/1193
 *
 */

 
#ifndef _ATALK_CNID__H
#define _ATALK_CNID__H 1
 
#include <errno.h>
#include <stdbool.h>
#include <stdint.h>
 
#include <atalk/adouble.h>
#include <atalk/list.h>
#include <atalk/uuid.h>
 
/* CNID object flags */
#define CNID_FLAG_PERSISTENT   0x01      
#define CNID_FLAG_MANGLING     0x02      
#define CNID_FLAG_SETUID       0x04      
#define CNID_FLAG_BLOCK        0x08      
#define CNID_FLAG_NODEV        0x10      
#define CNID_FLAG_LAZY_INIT    0x20
#define CNID_FLAG_INODE        0x80      
 
#define CNID_INVALID   0
#define CNID_START     17    
 
#define CNID_ERR_PARAM 0x80000001
#define CNID_ERR_PATH  0x80000002
#define CNID_ERR_DB    0x80000003   
#define CNID_ERR_CLOSE 0x80000004   
#define CNID_ERR_MAX   0x80000005
#define CNID_ERR_RESET 0x80000006   
#define CNID_ERR_BUSY  0x80000007   
#define CNID_ERR_CORRUPT 0x80000008 
#define CNID_ERR_NOTFOUND 0x80000009 
 
/* CNID_ERR_* exceed INT_MAX; compare against errno through this unsigned view */
#define CNID_ERRNO() ((unsigned int) errno)

#define CNID_ERRNO_IS_BACKEND_FAILURE()         \
    (CNID_ERRNO() == CNID_ERR_BUSY              \
     || CNID_ERRNO() == CNID_ERR_CORRUPT        \
     || CNID_ERRNO() == CNID_ERR_DB)
 
/* cnid_find() requires a result buffer large enough to hold at least one
 * full DBD-backend batch (CNID_FIND_MIN_RESULTS = 100 CNIDs in network
 * byte order). The cnid_find() wrapper enforces this minimum centrally
 * so every CNID backend behaves identically. */
#define CNID_FIND_MIN_RESULTS  100
#define CNID_FIND_MIN_BUFLEN   (CNID_FIND_MIN_RESULTS * sizeof(uint32_t))

typedef struct _cnid_db {
    /* Flags describing some CNID backend aspects. */
    uint32_t      cnid_db_flags;
    struct vol   *cnid_db_vol;
    /* back-end speficic data */
    void         *cnid_db_private;
 
    cnid_t (*cnid_add)(struct _cnid_db *cdb, const struct stat *st, cnid_t did,
                       const char *name, size_t, cnid_t hint);
    int (*cnid_delete)(struct _cnid_db *cdb, cnid_t id);
    cnid_t (*cnid_get)(struct _cnid_db *cdb, cnid_t did, const char *name,
                       size_t);
    cnid_t (*cnid_lookup)(struct _cnid_db *cdb, const struct stat *st,
                          cnid_t did, const char *name, size_t);
    cnid_t (*cnid_nextid)(struct _cnid_db *cdb);
    char *(*cnid_resolve)(struct _cnid_db *cdb, cnid_t *id, void *buffer,
                          size_t len);
    int (*cnid_update)(struct _cnid_db *cdb, cnid_t id, const struct stat *st,
                       cnid_t did, const char *name, size_t len);
    void (*cnid_close)(struct _cnid_db *cdb);
    int (*cnid_getstamp)(struct _cnid_db *cdb, void *buffer, const size_t len);
    cnid_t (*cnid_rebuild_add)(struct _cnid_db *, const struct stat *, cnid_t,
                               const char *, size_t, cnid_t);
    int (*cnid_find)(struct _cnid_db *cdb, const char *name, size_t namelen,
                     cnid_t scope_did,
                     void *buffer, size_t buflen, bool *more_available);
    int (*cnid_wipe)(struct _cnid_db *cdb);
} cnid_db;
 
/*
 * Consolidation of args passed from main cnid_open to modules cnid_XXX_open, so
 * that it's easier to add aditional args as required.
 */
struct cnid_open_args {
    uint32_t cnid_args_flags;
    struct vol *cnid_args_vol;
};
 
/*
 * CNID module - represents particular CNID implementation
 */
struct _cnid_module {
    char *name;
    /* CNID modules are also stored on a bidirectional list. */
    struct list_head db_list;
    struct _cnid_db *(*cnid_open)(struct cnid_open_args *args);
    /* Flags describing some CNID backend aspects. */
    uint32_t flags;
};
 
typedef struct _cnid_module cnid_module;
 
/* Inititalize the CNID backends */
void cnid_init(void);
 
/* Registers new CNID backend module */
void cnid_register(struct _cnid_module *module);
 
/* This function opens a CNID database for selected volume. */
struct _cnid_db *cnid_open(struct vol *vol, char *type, int flags);
cnid_t cnid_add(struct _cnid_db *cdb, const struct stat *st, const cnid_t did,
                const char *name, const size_t len, cnid_t hint);
int    cnid_delete(struct _cnid_db *cdb, cnid_t id);
cnid_t cnid_get(struct _cnid_db *cdb, const cnid_t did, char *name,
                const size_t len);
int    cnid_getstamp(struct _cnid_db *cdb, void *buffer, const size_t len);
cnid_t cnid_lookup(struct _cnid_db *cdb, const struct stat *st,
                   const cnid_t did, char *name, const size_t len);
char  *cnid_resolve(struct _cnid_db *cdb, cnid_t *id, void *buffer,
                    size_t len);
int    cnid_update(struct _cnid_db *cdb, const cnid_t id,
                   const struct stat *st, const cnid_t did, char *name,
                   const size_t len);
cnid_t cnid_rebuild_add(struct _cnid_db *cdb, const struct stat *st,
                        const cnid_t did, char *name, const size_t len,
                        cnid_t hint);
int    cnid_find(struct _cnid_db *cdb, const char *name, size_t namelen,
                 void *buffer, size_t buflen, bool *more_available);
int    cnid_find_scoped(struct _cnid_db *cdb, const char *name,
                        size_t namelen, cnid_t scope_did,
                        void *buffer, size_t buflen,
                        bool *more_available);
int    cnid_wipe(struct _cnid_db *cdb);
void   cnid_close(struct _cnid_db *db);
 
#endif