diff options
Diffstat (limited to 'src/lib-index/mail-transaction-log-private.h')
-rw-r--r-- | src/lib-index/mail-transaction-log-private.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/src/lib-index/mail-transaction-log-private.h b/src/lib-index/mail-transaction-log-private.h new file mode 100644 index 0000000..4961fe0 --- /dev/null +++ b/src/lib-index/mail-transaction-log-private.h @@ -0,0 +1,199 @@ +#ifndef MAIL_TRANSACTION_LOG_VIEW_H +#define MAIL_TRANSACTION_LOG_VIEW_H + +#include "buffer.h" +#include "mail-transaction-log.h" + +struct dotlock_settings; + +/* Synchronization can take a while sometimes, especially when copying lots of + mails. */ +#define MAIL_TRANSACTION_LOG_LOCK_TIMEOUT (3*60) +#define MAIL_TRANSACTION_LOG_DOTLOCK_CHANGE_TIMEOUT (3*60) + +#define MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file) ((file)->fd == -1) + +#define LOG_FILE_MODSEQ_CACHE_SIZE 10 + +struct modseq_cache { + uoff_t offset; + uint64_t highest_modseq; +}; + +struct mail_transaction_log_file { + struct mail_transaction_log *log; + /* Next file in the mail_transaction_log.files list. Sorted by + hdr.file_seq. */ + struct mail_transaction_log_file *next; + + /* refcount=0 is a valid state. files start that way, and they're + freed only when mail_transaction_logs_clean() is called. */ + int refcount; + + char *filepath; + int fd; + + /* Cached values for last stat()/fstat() */ + ino_t st_ino; + dev_t st_dev; + time_t last_mtime; + uoff_t last_size; + + /* Used to avoid logging mmap() errors too rapidly. */ + time_t last_mmap_error_time; + /* If non-NULL, the log file should be rotated. The string contains a + human-readable reason why the rotation was requested. */ + char *need_rotate; + + /* Copy of the log file header. Set when opened. */ + struct mail_transaction_log_header hdr; + /* Buffer that points to mmap_base */ + buffer_t mmap_buffer; + /* Buffer that can be used to access the log file contents. Either + points to mmap_buffer, or it's a copy of the file contents starting + from buffer_offset. */ + buffer_t *buffer; + /* Offset to log where the buffer starts from. 0 with mmaped log. */ + uoff_t buffer_offset; + /* If non-NULL, mmap()ed log file */ + void *mmap_base; + size_t mmap_size; + + /* Offset to log file how far it's been read. Usually it's the same + as the log file size. However, if the last multi-record transaction + wasn't fully written (or is in the middle of being written), this + points to the beginning of the MAIL_TRANSACTION_BOUNDARY record. */ + uoff_t sync_offset; + /* highest modseq at sync_offset */ + uint64_t sync_highest_modseq; + /* The last mail_index_header.log_file_tail_offset update that was + read from the log. */ + uoff_t last_read_hdr_tail_offset; + /* Update mail_index_header.log_file_tail_offset to this offset the + next time a transaction is written. Transaction log handling may + increase this automatically by making it skip external transactions + after last_read_hdr_tail_offset (to avoid re-reading them + needlessly). */ + uoff_t max_tail_offset; + + /* Last seen offsets for MAIL_TRANSACTION_INDEX_DELETED and + MAIL_TRANSACTION_INDEX_UNDELETED records. These are used to update + mail_index.index_delete* fields. */ + uoff_t index_deleted_offset, index_undeleted_offset; + + /* Cache to optimize mail_transaction_log_file_get_modseq_next_offset() + so it doesn't always have to start from the beginning of the log + file to find the wanted modseq. */ + struct modseq_cache modseq_cache[LOG_FILE_MODSEQ_CACHE_SIZE]; + + /* Lock for the log file fd. If dotlocking is used, this is NULL and + mail_transaction_log.dotlock is used instead. */ + struct file_lock *file_lock; + /* Time when the log was successfully locked */ + time_t lock_create_time; + + /* Log is currently locked. */ + bool locked:1; + /* TRUE if sync_offset has already been updated while this log was + locked. This can be used to optimize away unnecessary checks to see + whether there's more data written to log after sync_offset. */ + bool locked_sync_offset_updated:1; + /* Log file has found to be corrupted. Stop trying to read it. + The indexid is also usually overwritten to be 0 in the log header at + this time. */ + bool corrupted:1; +}; + +struct mail_transaction_log { + struct mail_index *index; + /* Linked list of all transaction log views */ + struct mail_transaction_log_view *views; + /* Paths to .log and .log.2 */ + char *filepath, *filepath2; + + /* Linked list of all the opened log files. The oldest files may have + already been unlinked. The list is sorted by the log file sequence + (oldest/lowest first), so that transaction views can use them + easily. */ + struct mail_transaction_log_file *files; + /* Latest log file (the last file in the files linked list) */ + struct mail_transaction_log_file *head; + /* open_file is used temporarily while opening the log file. + if mail_transaction_log_open() failed, it's left there for + mail_transaction_log_create(). */ + struct mail_transaction_log_file *open_file; + + /* Normally the .log locking is done via their file descriptors, so + e.g. rotating a log needs to lock both the old and the new files + at the same time. However, when FILE_LOCK_METHOD_DOTLOCK is used, + the lock isn't file-specific. There is just a single dotlock that + is created by the first log file lock. The second lock simply + increases the refcount. (It's not expected that there would be more + than 2 locks.) */ + int dotlock_refcount; + struct dotlock *dotlock; + + /* This session has already checked whether an old .log.2 should be + unlinked. */ + bool log_2_unlink_checked:1; +}; + +void +mail_transaction_log_file_set_corrupted(struct mail_transaction_log_file *file, + const char *fmt, ...) + ATTR_FORMAT(2, 3) ATTR_COLD; + +void mail_transaction_log_get_dotlock_set(struct mail_transaction_log *log, + struct dotlock_settings *set_r); + +struct mail_transaction_log_file * +mail_transaction_log_file_alloc_in_memory(struct mail_transaction_log *log); +struct mail_transaction_log_file * +mail_transaction_log_file_alloc(struct mail_transaction_log *log, + const char *path); +void mail_transaction_log_file_free(struct mail_transaction_log_file **file); + +/* Returns 1 if log was opened, 0 if it didn't exist or was already open, + -1 if error. */ +int mail_transaction_log_file_open(struct mail_transaction_log_file *file, + const char **reason_r); +int mail_transaction_log_file_create(struct mail_transaction_log_file *file, + bool reset); +int mail_transaction_log_file_lock(struct mail_transaction_log_file *file); + +int mail_transaction_log_find_file(struct mail_transaction_log *log, + uint32_t file_seq, bool nfs_flush, + struct mail_transaction_log_file **file_r, + const char **reason_r); + +/* Returns 1 if ok, 0 if file is corrupted or offset range is invalid, + -1 if I/O error */ +int mail_transaction_log_file_map(struct mail_transaction_log_file *file, + uoff_t start_offset, uoff_t end_offset, + const char **reason_r); +int mail_transaction_log_file_move_to_memory(struct mail_transaction_log_file *file); + +void mail_transaction_logs_clean(struct mail_transaction_log *log); + +bool mail_transaction_log_want_rotate(struct mail_transaction_log *log, + const char **reason_r); +int mail_transaction_log_rotate(struct mail_transaction_log *log, bool reset); +int mail_transaction_log_lock_head(struct mail_transaction_log *log, + const char *lock_reason); +void mail_transaction_log_file_unlock(struct mail_transaction_log_file *file, + const char *lock_reason); + +void mail_transaction_update_modseq(const struct mail_transaction_header *hdr, + const void *data, uint64_t *cur_modseq, + unsigned int version); +/* Returns 1 if ok, 0 if file is corrupted or offset range is invalid, + -1 if I/O error */ +int mail_transaction_log_file_get_highest_modseq_at( + struct mail_transaction_log_file *file, + uoff_t offset, uint64_t *highest_modseq_r, + const char **error_r); +int mail_transaction_log_file_get_modseq_next_offset( + struct mail_transaction_log_file *file, + uint64_t modseq, uoff_t *next_offset_r); + +#endif |