mail-index.h revision e6d35af29202a78abd9c6a8412f340693b36a948
#ifndef __MAIL_INDEX_H
#define __MAIL_INDEX_H
#include "byteorder.h"
#include "file-dotlock.h"
#include "message-parser.h"
#include "imap-util.h"
#define MAIL_INDEX_MAJOR_VERSION 3
#define MAIL_INDEX_MINOR_VERSION 0
#define INDEX_FILE_PREFIX ".imap.index"
enum mail_index_open_flags {
/* Create index if it doesn't exist */
MAIL_INDEX_OPEN_FLAG_CREATE = 0x01,
/* Update \Recent flag counters */
/* Compressing and cache updates are not performed */
MAIL_INDEX_OPEN_FLAG_FAST = 0x04,
/* Invalidate memory maps before accessing them */
/* internal: we're creating the index */
_MAIL_INDEX_OPEN_FLAG_CREATING = 0x100
};
enum mail_index_header_flag {
/* Rebuild flag is set while index is being rebuilt or when
some error is noticed in the index file. If this flag is set,
the index shouldn't be used before rebuilding it. */
};
enum mail_index_record_flag {
/* If binary flags are set, it's not checked whether mail is
missing CRs. So this flag may be set as an optimization for
regular non-binary mails as well if it's known that it contains
valid CR+LF line breaks. */
/* Mail flags have been changed in index, but not written into
actual mailbox yet. */
/* Maildir: Mail file is in new/ dir instead of cur/ */
/* Mail header or body is known to contain NUL characters. */
/* Mail header or body is known to not contain NUL characters. */
};
enum mail_lock_type {
MAIL_LOCK_UNLOCK = 0,
};
enum mail_lock_notify_type {
/* Mailbox is locked, will abort in secs_left */
/* Mailbox lock looks stale, will override in secs_left */
/* Index is locked, will abort in secs_left */
};
enum mail_index_error {
/* No errors */
/* Internal error, see get_error_text() for more information. */
/* Index is now in inconsistent state with the previous known state,
meaning that the message IDs etc. may have changed - only way to
recover this would be to fully close the mailbox and reopen it.
With IMAP this would mean a forced disconnection since we can't do
forced CLOSE. */
/* We ran out of available disk space. */
/* Mail index locking timeouted */
/* Mailbox locking timeouted */
};
struct mail_index_header {
/* major version is increased only when you can't have backwards
compatibility. minor version is increased when header size is
increased to contain new non-critical fields. */
if file size is shrinked */
/* these UIDs may not exist and may not even be unseen */
};
struct mail_index_record {
};
struct mail_index {
/* Note that opening same index twice in the same process is a bad
idea since they share the same file locks. As soon one of the
indexes is closed, the locks in second index are dropped which
especially hurts modify log since it keeps locks all the time. */
/* Free index from memory. */
reset error from get_last_error() as unlocking can be done as
a cleanup after some other function failed. Index is always
mmap()ed after set_lock() succeeds.
Trying to change a shared lock into exclusive lock is a fatal
error, since it may create a deadlock. Even though operating
system should detect it and fail, it's not a good idea to even
let it happen. Better ways to do this would be to a) mark the
data to be updated later, b) use try_lock() if the update is
preferred but not required, c) unlock + lock again, but make
sure that won't create race conditions. */
enum mail_lock_type lock_type);
/* Try locking the index. Returns TRUE if the lock was got and
FALSE if lock isn't possible to get currently or some other error
occured. Never blocks. */
enum mail_lock_type lock_type);
/* If we have to wait for the lock, the given lock notify function
is called once in a while. */
void *context);
/* Rebuild the whole index. Note that this changes the indexid
so all the other files must also be rebuilt after this call.
Index MUST NOT have shared lock, but exclusive lock or no lock at
all is fine. Note that this function may leave the index
exclusively locked, and always sets index->inconsistent = TRUE. */
/* Verify that the index is valid. If anything invalid is found,
index is set inconsistent and to be rebuilt at next open.
Same locking issues as with rebuild(). */
/* Synchronize the index with the mailbox. Index must not have shared
lock when calling this function. The data_lock_type specifies what
lock should be set to data file (mbox file). This function may
leave the index in ANY locking state. If changes is non-NULL, it's
set to TRUE if any changes were noticed. If minimal_sync is TRUE,
we do as little as possible to get data file locked (ie. noop with
maildir). */
/* Returns the index header (never fails). The index needs to be
locked before calling this function, and must be kept locked as
long as you keep using the returned structure. */
/* sequence -> data lookup. The index needs to be locked before calling
this function, and must be kept locked as long as you keep using
the returned structure. */
unsigned int seq);
/* Return the next record after specified record, or NULL if it was
last record. The index must be locked all the time between
lookup() and last next() call. rec must not have been expunged. */
struct mail_index_record *rec);
/* Find first existing UID in range. Sequence number is also retrieved
if seq_r is non-NULL. */
unsigned int first_uid,
unsigned int last_uid,
unsigned int *seq_r);
/* Open mail file and return it as mmap()ed IStream. If we fail,
we return NULL and set deleted = TRUE if failure was because the
mail was just deleted (ie. not an error). received_date is set
if it's non-NULL. */
struct mail_index_record *rec,
/* Returns received date of message, or (time_t)-1 if error occured. */
struct mail_index_record *rec);
/* Expunge mails from index. Modifylog is also updated. The
index must be exclusively locked before calling this function.
first_rec+1 .. last_rec-1 range may contain already expunged
records.
Note that all record pointers are invalidated after this call as
expunging may radically modify the file. */
struct mail_index_record *first_rec,
struct mail_index_record *last_rec,
int external_change);
/* Update mail flags. The index must be exclusively locked before
calling this function. */
int external_change);
/* Append a new record to index. The index must be exclusively
locked before calling this function. */
/* Returns the last error code. */
/* Returns the full error message for last error. This message may
contain paths etc. so it shouldn't be shown to users. */
/* private: */
struct mail_cache *cache;
struct mail_modify_log *modifylog;
struct mail_custom_flags *custom_flags;
char *dir; /* directory where to place the index files */
char *filepath; /* index file path */
char *mailbox_path; /* file/directory for mailbox location */
char *control_dir; /* destination for control files */
unsigned int indexid;
unsigned int sync_id;
unsigned int excl_lock_counter;
/* updated whenever expunge() is called */
unsigned int expunge_counter;
int mbox_fd;
struct istream *mbox_stream;
enum mail_lock_type mbox_lock_type;
struct dotlock mbox_dotlock;
/* these counters can be used to check that we've synced the mailbox
after locking it */
unsigned int mbox_lock_counter;
unsigned int mbox_sync_counter;
/* last mbox sync: */
/* last maildir sync: */
int maildir_lock_fd;
struct hash_table *new_filenames;
int fd; /* opened index file */
char *error; /* last error message */
void *mmap_base;
struct mail_index_header *header;
enum mail_lock_type lock_type;
unsigned int first_recent_uid;
void *lock_notify_context;
/* these fields are OR'ed to the fields in index header once we
get around grabbing exclusive lock */
unsigned int set_flags;
unsigned int cache_later_locks;
unsigned int anon_mmap:1;
unsigned int mmap_invalidate:1;
unsigned int opened:1;
unsigned int rebuilding:1;
unsigned int mail_read_mmaped:1;
unsigned int inconsistent:1;
unsigned int nodiskspace:1;
unsigned int index_lock_timeout:1;
unsigned int allow_new_custom_flags:1;
unsigned int mailbox_readonly:1;
unsigned int mailbox_lock_timeout:1;
unsigned int maildir_keep_new:1;
unsigned int maildir_have_new:1;
unsigned int maildir_synced_once:1;
};
#ifdef DEV_T_STRUCT
/* we can't initialize dev_t as 0, and we don't know what it actually
contains, so don't initialize them. gcc's -W option should be disabled
with this or we get warnings.. */
# define MAIL_INDEX_PRIVATE_FILL 0
#else
/* needed to remove annoying warnings about not initializing all struct
members.. */
#define MAIL_INDEX_PRIVATE_FILL \
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
0, 0, 0, 0, { 0, 0, 0 }, 0, 0, 0, \
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
0, 0, 0, 0, 0, 0, 0
#endif
/* defaults - same as above but prefixed with mail_index_. */
enum mail_lock_type lock_type);
enum mail_lock_type lock_type);
void *context);
unsigned int seq);
struct mail_index_record *rec);
struct mail_index_record *
struct mail_index_record *first_rec,
struct mail_index_record *last_rec,
int external_change);
int external_change);
/* INTERNAL: */
struct mail_index_record *rec,
enum mail_flags old_flags,
enum mail_flags new_flags);
struct mail_index_record *first_rec,
struct mail_index_record *last_rec);
/* Maximum allowed UID number. */
/* Max. mmap()ed size for a message */
/* Block size when read()ing message. */
/* Delete unused non-local temp files after 24h. Just to be sure we don't
delete it too early. The temp files don't harm much anyway. */
/* number of records to always keep allocated in index file,
either used or unused */
#define INDEX_MIN_RECORDS_COUNT 64
/* when empty space in index file gets full, grow the file n% larger */
#define INDEX_GROW_PERCENTAGE 10
/* ftruncate() the index file when only n% of it is in use */
#define INDEX_TRUNCATE_PERCENTAGE 30
/* don't truncate whole file anyway, keep n% of the empty space */
#define INDEX_TRUNCATE_KEEP_PERCENTAGE 10
/* Compress the file when deleted space reaches n% of total size */
#define INDEX_COMPRESS_PERCENTAGE 50
/* Compress the file when searching deleted records tree has to go this deep */
#define INDEX_COMPRESS_DEPTH 10
/* uoff_t to index file for given record */
/* record for given index */
((struct mail_index_record *) \
/* returns the next record after last one */
#define INDEX_END_RECORD(index) \
((struct mail_index_record *) \
/* index number for uoff_t position */
sizeof(struct mail_index_record))
/* index number for given record */
/* mark the index corrupted */
#define INDEX_MARK_CORRUPTED(index) \
STMT_START { \
} STMT_END
/* get number of records in mmaped index */
#define MAIL_INDEX_RECORD_COUNT(index) \
sizeof(struct mail_index_record))
/* minimum size for index file */
#define INDEX_FILE_MIN_SIZE(index) \
((index)->header_size + \
INDEX_MIN_RECORDS_COUNT * sizeof(struct mail_index_record))
/* enum mail_lock_type to fcntl() lock type */
#define MAIL_LOCK_TO_FLOCK(lock_type) \
#define INDEX_IS_IN_MEMORY(index) \
/* Returns alignmentation for given size */
#define INDEX_ALIGN(size) \
#endif