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

	mail-index-private.h revision a2645bdd6547b87e2380f33ce78640118b9e9e68
#ifndef __MAIL_INDEX_PRIVATE_H
#define __MAIL_INDEX_PRIVATE_H

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

struct mail_transaction_header;

/* Maximum number of extra record data items we allowed. Raising this limit
   only means it takes a few bytes more memory, but 32 should be enough for a
   long time, right? :) */
#define MAIL_INDEX_MAX_EXTRA_RECORDS 32

/* 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))

struct mail_index_extra_record_info {
    const char *name;
    uint16_t offset;
    uint16_t size;
};

struct mail_index_map {
    int refcount;

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

    struct mail_index_extra_record_info *
        extra_record_map[MAIL_INDEX_MAX_EXTRA_RECORDS];

    void *mmap_base;
    size_t mmap_size, mmap_used_size;

    buffer_t *buffer;

    uint32_t log_file_seq;
    uoff_t log_file_offset;

    struct mail_index_header hdr_copy;
    uint32_t base_header_size; /* so we don't need lock to access it */

    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 extra_records_pool;
    buffer_t *extra_records_buf;
    const struct mail_index_extra_record_info *extra_records;
    unsigned int extra_records_count;
    unsigned int max_record_size;

    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;

    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 fcntl_locks_disable:1;
    unsigned int readonly:1;
    unsigned int fsck:1;
};

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_map_lock_mprotect(struct mail_index *index,
                 struct mail_index_map *map, int lock_type);

/* 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_to_memory(struct mail_index_map *map, uint32_t new_record_size);

int mail_index_lookup_full(struct mail_index_view *view, uint32_t seq,
               struct mail_index_map **map_r,
               const struct mail_index_record **rec_r);

void mail_index_reset_cache(struct mail_index_transaction *t,
                uint32_t new_file_seq);
void mail_index_update_cache(struct mail_index_transaction *t, uint32_t seq,
                 uint32_t file_seq, uint32_t offset,
                 uint32_t *old_offset_r);

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);

#endif