#ifndef _LVD_MAP_H_
#define _LVD_MAP_H_
#include <stdint.h>
#include <sys/types.h>
/*
* LVD per-domain registry — single C implementation for liblve.so.
*
* Two file types live under LVD_MAP_DIR:
*
* <uid> Per-uid open-addressing hash table (docroot -> domain_id).
* The hot lookup path touches only this file — no locking,
* no .index access.
*
* .index Global next_id counter (12 bytes). Touched only on writes
* (assign/remove), under flock().
*
* Per-uid on-disk format (version 2):
*
* Header (16 bytes):
* magic[4] = "LVDM"
* version(u16) = 2
* count(u16) — number of occupied slots
* str_offset(u32)— byte offset from file start to string pool
* capacity(u32) — hash table slot count (power of 2)
*
* Hash table (capacity * 16 bytes, starts at byte 16):
* Per slot (16 bytes):
* hash(u32) — FNV-1a of docroot; 0 = empty slot
* key_offset(u32)— offset into string pool (from pool start)
* key_len(u32) — docroot string length (excluding NUL)
* domain_id(u32) — assigned domain LVE ID
*
* String pool (at str_offset):
* Packed null-terminated docroot strings
*
* Version 1 (legacy sorted-array format) is still accepted by
* lvd_map_lookup() for transparent migration.
*/
#define LVD_MAP_MAGIC "LVDM"
#define LVD_MAP_VERSION 2
#define LVD_MAP_DIR "/etc/container/lvd_ids"
/* Legacy format version for backward-compatible reads */
#define LVD_MAP_VERSION_V1 1
struct lvd_map_header {
char magic[4];
uint16_t version;
uint16_t count;
uint32_t str_offset;
uint32_t capacity; /* v2: hash table slot count; v1: reserved */
} __attribute__((packed));
struct lvd_map_slot {
uint32_t hash; /* FNV-1a of docroot; 0 = empty */
uint32_t key_offset; /* offset into string pool */
uint32_t key_len; /* docroot length (no NUL) */
uint32_t domain_id;
} __attribute__((packed));
/* Legacy v1 entry (12 bytes, sorted by docroot) */
struct lvd_map_entry_v1 {
uint32_t key_offset;
uint32_t key_len;
uint32_t domain_id;
} __attribute__((packed));
/* ------------------------------------------------------------------ */
/* Hash */
/* ------------------------------------------------------------------ */
uint32_t lvd_fnv1a(const char *docroot);
/* ------------------------------------------------------------------ */
/* Read-only (no locking, no .index access) */
/* ------------------------------------------------------------------ */
uint32_t lvd_map_lookup(uid_t uid, const char *docroot);
int lvd_map_verify_ownership(uid_t uid, uint32_t domain_id);
/* ------------------------------------------------------------------ */
/* Iteration (opendir/readdir style — zero-copy, mmap-backed) */
/* ------------------------------------------------------------------ */
typedef struct lvd_iter lvd_iter_t;
lvd_iter_t *lvd_map_iter_open(uid_t uid);
int lvd_map_iter_next(lvd_iter_t *it,
const char **docroot,
uint32_t *domain_id);
void lvd_map_iter_close(lvd_iter_t *it);
/* ------------------------------------------------------------------ */
/* Read-write (acquires flock on .index) */
/* ------------------------------------------------------------------ */
int lvd_map_assign(uid_t uid, const char *docroot, uint32_t *out_id);
int lvd_map_remove(uid_t uid, const char *docroot, uint32_t *old_id);
int lvd_map_remove_all(uid_t uid);
/* ------------------------------------------------------------------ */
/* Index management */
/* ------------------------------------------------------------------ */
int lvd_index_rebuild(void);
/* ------------------------------------------------------------------ */
/* Domain ID threshold */
/* ------------------------------------------------------------------ */
/*
* Minimum domain LVE ID — reads UID_MAX from /etc/login.defs at runtime.
* Returns max(UID_MAX, LVD_UID_MAX_DEFAULT) so domain IDs never go
* below the compile-time floor (60000).
*/
uint32_t lvd_get_id_min(void);
#endif /* _LVD_MAP_H_ */
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