src/lib-index/mail-index-private.h

	mail-index-private.h revision f23298fea47eecbeded985ee2537a34c4c4ef56b
#ifndef __MAIL_INDEX_PRIVATE_H
#define __MAIL_INDEX_PRIVATE_H

/* Make sure F_RDLCK, F_WRLCK and F_UNLCK get defined */
#include <unistd.h>
#include <fcntl.h>

#include "file-dotlock.h"
#include "mail-index.h"

struct mail_transaction_header;
struct mail_index_sync_map_ctx;

/* How many seconds to wait a lock for index file. */
#define MAIL_INDEX_LOCK_SECS 120
/* Index file is grown exponentially when we're adding less than this many
   records. */
#define MAIL_INDEX_MAX_POWER_GROW (1024*1024 / sizeof(struct mail_index_record))
/* How many times to retry opening index files if read/fstat returns ESTALE.
   This happens with NFS when the file has been deleted (ie. index file was
   rewritten by another computer than us). */
#define MAIL_INDEX_ESTALE_RETRY_COUNT 10

#define MAIL_INDEX_MAP_IS_IN_MEMORY(map) \
    ((map)->buffer != NULL)

#define MAIL_INDEX_MAP_IDX(map, idx) \
    ((struct mail_index_record *) \
        PTR_OFFSET((map)->records, (idx) * (map)->hdr.record_size))

typedef int mail_index_expunge_handler_t(struct mail_index_sync_map_ctx *ctx,
                     uint32_t seq, const void *data,
                     void **context);
typedef int mail_index_sync_handler_t(struct mail_index_sync_map_ctx *ctx,
                      uint32_t seq, void *old_data,
                      const void *new_data, void **context);
typedef void mail_index_sync_lost_handler_t(struct mail_index *index);

#define MAIL_INDEX_HEADER_SIZE_ALIGN(size) \
    (((size) + 7) & ~7)

struct mail_index_ext {
    const char *name;
    uint32_t index_idx; /* index ext_id */
    uint32_t reset_id;
    uint32_t hdr_offset;
    uint32_t hdr_size;
    uint16_t record_offset;
    uint16_t record_size;
    uint16_t record_align;
};

struct mail_index_ext_header {
    uint32_t hdr_size;
    uint32_t reset_id;
    uint16_t record_offset;
    uint16_t record_size;
    uint16_t record_align;
    uint16_t name_size;
    /* unsigned char name[] */
};

struct mail_index_map {
    int refcount;

    struct mail_index_header hdr;
    const void *hdr_base;
    void *records; /* struct mail_index_record[] */
    unsigned int records_count;

    pool_t extension_pool;
    buffer_t *extensions; /* struct mail_index_ext[] */
    buffer_t *ext_id_map; /* uint32_t[] (index -> file) */

    void *mmap_base;
    size_t mmap_size, mmap_used_size;

    buffer_t *buffer;
    buffer_t *hdr_copy_buf;

    unsigned int write_to_disk:1;
};

struct mail_index {
    char *dir, *prefix;

    struct mail_cache *cache;
    struct mail_transaction_log *log;

    mode_t mode;
    gid_t gid;

    pool_t extension_pool;
    buffer_t *extensions; /* struct mail_index_ext[] */

    buffer_t *expunge_handlers; /* mail_index_expunge_handler_t*[] */
    buffer_t *sync_handlers; /* mail_index_sync_handler_t*[] */
    buffer_t *sync_lost_handlers; /* mail_index_sync_lost_handler_t*[] */

    char *filepath;
    int fd;

        struct mail_index_map *map;
    const struct mail_index_header *hdr;
    uint32_t indexid;

    int lock_type, shared_lock_count, excl_lock_count;
    unsigned int lock_id;
    char *copy_lock_path;
    struct dotlock dotlock;
        enum mail_index_lock_method lock_method;

    /* These are typically same as map->hdr->log_file_*, but with
       mmap_disable we may have synced more than index */
    uint32_t sync_log_file_seq;
    uoff_t sync_log_file_offset;

    unsigned int last_grow_count;

    char *error;
    unsigned int nodiskspace:1;
    unsigned int index_lock_timeout:1;

    unsigned int opened:1;
    unsigned int log_locked:1;
    unsigned int mmap_disable:1;
    unsigned int mmap_no_write:1;
    unsigned int readonly:1;
    unsigned int fsck:1;
};

enum mail_index_sync_handler_type {
    MAIL_INDEX_SYNC_HANDLER_INDEX   = 0x01,
    MAIL_INDEX_SYNC_HANDLER_VIEW    = 0x02
};

struct mail_index_sync_handler {
    mail_index_sync_handler_t *callback;
        enum mail_index_sync_handler_type type;
};

/* Add/replace sync handler for specified extra record. */
void mail_index_register_expunge_handler(struct mail_index *index,
                     uint32_t ext_id,
                     mail_index_expunge_handler_t *cb);
void mail_index_register_sync_handler(struct mail_index *index, uint32_t ext_id,
                      mail_index_sync_handler_t *cb,
                      enum mail_index_sync_handler_type type);
void mail_index_register_sync_lost_handler(struct mail_index *index,
                       mail_index_sync_lost_handler_t *cb);

int mail_index_write_base_header(struct mail_index *index,
                 const struct mail_index_header *hdr);

int mail_index_reopen(struct mail_index *index, int fd);
int mail_index_create_tmp_file(struct mail_index *index, const char **path_r);

/* Returns 0 = ok, -1 = error. If update_index is TRUE, reopens the index
   file if needed to get later version of it (not necessarily latest due to
   races, unless transaction log is exclusively locked). */
int mail_index_lock_shared(struct mail_index *index, int update_index,
               unsigned int *lock_id_r);
/* Returns 0 = ok, -1 = error. */
int mail_index_lock_exclusive(struct mail_index *index,
                  unsigned int *lock_id_r);
void mail_index_unlock(struct mail_index *index, unsigned int lock_id);
/* Returns 1 if given lock_id is valid, 0 if not. */
int mail_index_is_locked(struct mail_index *index, unsigned int lock_id);

int mail_index_lock_fd(struct mail_index *index, int fd, int lock_type,
               unsigned int timeout_secs);

/* Reopen index file if it has changed. */
int mail_index_refresh(struct mail_index *index);

/* Map index file to memory, replacing the previous mapping for index.
   Returns 1 = ok, 0 = corrupted, -1 = error. If index needs fscking, it
   returns 1 but sets index->fsck = TRUE. */
int mail_index_map(struct mail_index *index, int force);
/* Unreference given mapping and unmap it if it's dropped to zero. */
void mail_index_unmap(struct mail_index *index, struct mail_index_map *map);
struct mail_index_map *
mail_index_map_clone(struct mail_index_map *map, uint32_t new_record_size);

uint32_t mail_index_map_lookup_ext(struct mail_index_map *map,
                   const char *name);
uint32_t
mail_index_map_register_ext(struct mail_index *index,
                struct mail_index_map *map, const char *name,
                uint32_t hdr_offset, uint32_t hdr_size,
                uint32_t record_offset, uint32_t record_size,
                uint32_t record_align, uint32_t reset_id);
int mail_index_map_get_ext_idx(struct mail_index_map *map,
                   uint32_t ext_id, uint32_t *idx_r);
const struct mail_index_ext *
mail_index_view_get_ext(struct mail_index_view *view, uint32_t ext_id);

int mail_index_fix_header(struct mail_index *index, struct mail_index_map *map,
              struct mail_index_header *hdr, const char **error_r);

void mail_index_view_transaction_ref(struct mail_index_view *view);
void mail_index_view_transaction_unref(struct mail_index_view *view);

void mail_index_set_inconsistent(struct mail_index *index);

int mail_index_set_error(struct mail_index *index, const char *fmt, ...)
    __attr_format__(2, 3);
/* "%s failed with index file %s: %m" */
int mail_index_set_syscall_error(struct mail_index *index,
                 const char *function);
/* "%s failed with file %s: %m" */
int mail_index_file_set_syscall_error(struct mail_index *index,
                      const char *filepath,
                      const char *function);
void mail_index_reset_error(struct mail_index *index);

uint32_t mail_index_uint32_to_offset(uint32_t offset);
uint32_t mail_index_offset_to_uint32(uint32_t offset);

#endif