Adding upstream version 1:2.3.19.1+dfsg1.upstream/1%2.3.19.1+dfsg1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 913 insertions, 0 deletions

diff --git a/src/lib-storage/mail-storage-private.h b/src/lib-storage/mail-storage-private.h
new file mode 100644
index 0000000..bc462bb
--- /dev/null
+++ b/src/lib-storage/mail-storage-private.h
@@ -0,0 +1,913 @@
+#ifndef MAIL_STORAGE_PRIVATE_H
+#define MAIL_STORAGE_PRIVATE_H
+
+#include "module-context.h"
+#include "unichar.h"
+#include "file-lock.h"
+#include "mail-storage.h"
+#include "mail-storage-hooks.h"
+#include "mail-storage-settings.h"
+#include "mailbox-attribute-private.h"
+#include "mail-index-private.h"
+
+struct file_lock;
+struct file_create_settings;
+struct fs;
+
+/* Default prefix for indexes */
+#define MAIL_INDEX_PREFIX "dovecot.index"
+
+/* Block size when read()ing message header. */
+#define MAIL_READ_HDR_BLOCK_SIZE (1024*4)
+/* Block size when read()ing message (header and) body. */
+#define MAIL_READ_FULL_BLOCK_SIZE IO_BLOCK_SIZE
+
+#define MAIL_SHARED_STORAGE_NAME "shared"
+
+#define MAIL_STORAGE_LOST_MAILBOX_PREFIX "recovered-lost-folder-"
+
+enum mail_storage_list_index_rebuild_reason {
+	/* Mailbox list index was found to be corrupted. */
+	MAIL_STORAGE_LIST_INDEX_REBUILD_REASON_CORRUPTED,
+	/* Mailbox list index doesn't have INBOX in an inbox=yes namespace.
+	   Rebuild is done to verify whether the user really is an empty new
+	   user, or if an existing user's mailbox list index was lost. Because
+	   this is called in non-error conditions, the callback shouldn't log
+	   any errors or warnings if it didn't find any missing mailboxes. */
+	MAIL_STORAGE_LIST_INDEX_REBUILD_REASON_NO_INBOX,
+	/* MAILBOX_SYNC_FLAG_FORCE_RESYNC is run. This is called only once
+	   per list, so that doveadm force-resync '*' won't cause it to run for
+	   every mailbox. */
+	MAIL_STORAGE_LIST_INDEX_REBUILD_REASON_FORCE_RESYNC,
+};
+
+struct mail_storage_module_register {
+	unsigned int id;
+};
+
+struct mail_module_register {
+	unsigned int id;
+};
+
+struct mail_storage_vfuncs {
+	const struct setting_parser_info *(*get_setting_parser_info)(void);
+
+	struct mail_storage *(*alloc)(void);
+	int (*create)(struct mail_storage *storage, struct mail_namespace *ns,
+		      const char **error_r);
+	void (*destroy)(struct mail_storage *storage);
+	void (*add_list)(struct mail_storage *storage,
+			 struct mailbox_list *list);
+
+	void (*get_list_settings)(const struct mail_namespace *ns,
+				  struct mailbox_list_settings *set);
+	bool (*autodetect)(const struct mail_namespace *ns,
+			   struct mailbox_list_settings *set);
+
+	struct mailbox *(*mailbox_alloc)(struct mail_storage *storage,
+					 struct mailbox_list *list,
+					 const char *vname,
+					 enum mailbox_flags flags);
+	int (*purge)(struct mail_storage *storage);
+	/* Called when mailbox list index rebuild is requested.
+	   The callback should add any missing mailboxes to the list index.
+	   Returns 0 on success, -1 on temporary failure that didn't properly
+	   rebuild the index. */
+	int (*list_index_rebuild)(struct mail_storage *storage,
+				  enum mail_storage_list_index_rebuild_reason reason);
+};
+
+union mail_storage_module_context {
+	struct mail_storage_vfuncs super;
+	struct mail_storage_module_register *reg;
+};
+
+enum mail_storage_class_flags {
+	/* mailboxes are files, not directories */
+	MAIL_STORAGE_CLASS_FLAG_MAILBOX_IS_FILE	= 0x01,
+	/* root_dir points to a unique directory */
+	MAIL_STORAGE_CLASS_FLAG_UNIQUE_ROOT	= 0x02,
+	/* mailbox_open_stream() is supported */
+	MAIL_STORAGE_CLASS_FLAG_OPEN_STREAMS	= 0x04,
+	/* never use quota for this storage (e.g. virtual mailboxes) */
+	MAIL_STORAGE_CLASS_FLAG_NOQUOTA		= 0x08,
+	/* Storage doesn't need a mail root directory */
+	MAIL_STORAGE_CLASS_FLAG_NO_ROOT		= 0x10,
+	/* Storage uses one file per message */
+	MAIL_STORAGE_CLASS_FLAG_FILE_PER_MSG	= 0x20,
+	/* Messages have GUIDs (always set mailbox_status.have_guids=TRUE) */
+	MAIL_STORAGE_CLASS_FLAG_HAVE_MAIL_GUIDS	= 0x40,
+	/* mailbox_save_set_guid() works (always set
+	   mailbox_status.have_save_guids=TRUE) */
+	MAIL_STORAGE_CLASS_FLAG_HAVE_MAIL_SAVE_GUIDS	= 0x80,
+	/* message content can be unstructured binary data
+	   (e.g. zlib plugin is allowed to compress/decompress mails) */
+	MAIL_STORAGE_CLASS_FLAG_BINARY_DATA	= 0x100,
+	/* Message GUIDs can only be 128bit (always set
+	   mailbox_status.have_only_guid128) */
+	MAIL_STORAGE_CLASS_FLAG_HAVE_MAIL_GUID128 = 0x200,
+	/* Storage deletes all files internally - mailbox list's
+	   delete_mailbox() shouldn't delete anything itself. */
+	MAIL_STORAGE_CLASS_FLAG_NO_LIST_DELETES	= 0x400,
+	/* Storage creates a secondary index */
+	MAIL_STORAGE_CLASS_FLAG_SECONDARY_INDEX	= 0x800,
+};
+
+struct mail_binary_cache {
+	struct timeout *to;
+	struct mailbox *box;
+	uint32_t uid;
+
+	uoff_t orig_physical_pos;
+	bool include_hdr;
+	struct istream *input;
+	uoff_t size;
+};
+
+struct mail_storage_error {
+	char *error_string;
+	enum mail_error error;
+	char *last_internal_error;
+	bool last_error_is_internal;
+};
+
+struct mail_storage {
+	const char *name;
+	enum mail_storage_class_flags class_flags;
+	/* Fields that the storage backend can get by other means than parsing
+	   the message header/body. For example the imapc backend can lookup
+	   MAIL_FETCH_IMAP_BODYSTRUCTURE from the remote server. Adding fields
+	   here avoids adding them to index_mail_data.access_part. */
+	enum mail_fetch_field nonbody_access_fields;
+	struct event_category *event_category;
+
+        struct mail_storage_vfuncs v, *vlast;
+
+/* private: */
+	pool_t pool;
+	struct mail_storage *prev, *next;
+	/* counting number of times mail_storage_create() has returned this
+	   same storage. */
+	int refcount;
+	/* counting number of objects (e.g. mailbox) that have a pointer
+	   to this storage. */
+	int obj_refcount;
+	/* Linked list of all mailboxes in the storage */
+	struct mailbox *mailboxes;
+	/* A "root dir" to enable storage sharing.  It is only ever used for
+	 * uniqueness checking (via strcmp) and never used as a path. */
+	const char *unique_root_dir;
+
+	/* prefix for lost mailbox */
+	const char *lost_mailbox_prefix;
+
+	/* Last error set in mail_storage_set_critical(). */
+	char *last_internal_error;
+
+	char *error_string;
+	enum mail_error error;
+	ARRAY(struct mail_storage_error) error_stack;
+	struct event *event;
+
+        const struct mail_storage *storage_class;
+	struct mail_user *user;
+	const char *temp_path_prefix;
+	const struct mail_storage_settings *set;
+
+	enum mail_storage_flags flags;
+
+	struct mail_storage_callbacks callbacks;
+	void *callback_context;
+
+	struct mail_binary_cache binary_cache;
+	/* Filled lazily by mailbox_attribute_*() when accessing shared
+	   attributes. */
+	struct dict *_shared_attr_dict;
+
+	/* optional fs-api object for accessing mailboxes */
+	struct fs *mailboxes_fs;
+
+	/* Module-specific contexts. See mail_storage_module_id. */
+	ARRAY(union mail_storage_module_context *) module_contexts;
+
+	/* Failed to create shared attribute dict, don't try again */
+	bool shared_attr_dict_failed:1;
+	bool last_error_is_internal:1;
+	bool rebuilding_list_index:1;
+	bool rebuild_list_index:1;
+};
+
+struct mail_attachment_part {
+	struct message_part *part;
+	const char *content_type, *content_disposition;
+};
+
+struct virtual_mailbox_vfuncs {
+	/* convert backend UIDs to virtual UIDs. if some backend UID doesn't
+	   exist in mailbox, it's simply ignored */
+	void (*get_virtual_uids)(struct mailbox *box,
+				 struct mailbox *backend_mailbox,
+				 const ARRAY_TYPE(seq_range) *backend_uids,
+				 ARRAY_TYPE(seq_range) *virtual_uids_r);
+	/* like get_virtual_uids(), but if a backend UID doesn't exist,
+	   convert it to 0. */
+	void (*get_virtual_uid_map)(struct mailbox *box,
+				    struct mailbox *backend_mailbox,
+				    const ARRAY_TYPE(seq_range) *backend_uids,
+				    ARRAY_TYPE(uint32_t) *virtual_uids_r);
+	void (*get_virtual_backend_boxes)(struct mailbox *box,
+					  ARRAY_TYPE(mailboxes) *mailboxes,
+					  bool only_with_msgs);
+};
+
+struct mailbox_vfuncs {
+	bool (*is_readonly)(struct mailbox *box);
+
+	int (*enable)(struct mailbox *box, enum mailbox_feature features);
+	int (*exists)(struct mailbox *box, bool auto_boxes,
+		      enum mailbox_existence *existence_r);
+	int (*open)(struct mailbox *box);
+	void (*close)(struct mailbox *box);
+	void (*free)(struct mailbox *box);
+
+	int (*create_box)(struct mailbox *box,
+			  const struct mailbox_update *update, bool directory);
+	int (*update_box)(struct mailbox *box,
+			  const struct mailbox_update *update);
+	int (*delete_box)(struct mailbox *box);
+	int (*rename_box)(struct mailbox *src, struct mailbox *dest);
+
+	int (*get_status)(struct mailbox *box, enum mailbox_status_items items,
+			  struct mailbox_status *status_r);
+	int (*get_metadata)(struct mailbox *box,
+			    enum mailbox_metadata_items items,
+			    struct mailbox_metadata *metadata_r);
+	int (*set_subscribed)(struct mailbox *box, bool set);
+
+	int (*attribute_set)(struct mailbox_transaction_context *t,
+			     enum mail_attribute_type type_flags,
+			     const char *key,
+			     const struct mail_attribute_value *value);
+	int (*attribute_get)(struct mailbox *box,
+			     enum mail_attribute_type type_flags,
+			     const char *key,
+			     struct mail_attribute_value *value_r);
+	struct mailbox_attribute_iter *
+		(*attribute_iter_init)(struct mailbox *box,
+				       enum mail_attribute_type type_flags,
+				       const char *prefix);
+	const char *(*attribute_iter_next)(struct mailbox_attribute_iter *iter);
+	int (*attribute_iter_deinit)(struct mailbox_attribute_iter *iter);
+
+	/* Lookup sync extension record and figure out if it mailbox has
+	   changed since. Returns 1 = yes, 0 = no, -1 = error. if quick==TRUE,
+	   return 1 if it's too costly to find out exactly. The reason_r is
+	   set if 1 is returned. */
+	int (*list_index_has_changed)(struct mailbox *box,
+				      struct mail_index_view *list_view,
+				      uint32_t seq, bool quick,
+				      const char **reason_r);
+	/* Update the sync extension record. */
+	void (*list_index_update_sync)(struct mailbox *box,
+				       struct mail_index_transaction *trans,
+				       uint32_t seq);
+
+	struct mailbox_sync_context *
+		(*sync_init)(struct mailbox *box,
+			     enum mailbox_sync_flags flags);
+	bool (*sync_next)(struct mailbox_sync_context *ctx,
+			  struct mailbox_sync_rec *sync_rec_r);
+	int (*sync_deinit)(struct mailbox_sync_context *ctx,
+			   struct mailbox_sync_status *status_r);
+
+	/* Called once for each expunge. Called one or more times for
+	   flag/keyword changes. Once the sync is finished, called with
+	   uid=0 and sync_type=0. */
+	void (*sync_notify)(struct mailbox *box, uint32_t uid,
+			    enum mailbox_sync_type sync_type);
+
+	void (*notify_changes)(struct mailbox *box);
+
+	struct mailbox_transaction_context *
+		(*transaction_begin)(struct mailbox *box,
+				     enum mailbox_transaction_flags flags,
+				     const char *reason);
+	int (*transaction_commit)(struct mailbox_transaction_context *t,
+				  struct mail_transaction_commit_changes *changes_r);
+	void (*transaction_rollback)(struct mailbox_transaction_context *t);
+
+	enum mail_flags (*get_private_flags_mask)(struct mailbox *box);
+
+	struct mail *
+		(*mail_alloc)(struct mailbox_transaction_context *t,
+			      enum mail_fetch_field wanted_fields,
+			      struct mailbox_header_lookup_ctx *wanted_headers);
+
+	struct mail_search_context *
+	(*search_init)(struct mailbox_transaction_context *t,
+		       struct mail_search_args *args,
+		       const enum mail_sort_type *sort_program,
+		       enum mail_fetch_field wanted_fields,
+		       struct mailbox_header_lookup_ctx *wanted_headers);
+	int (*search_deinit)(struct mail_search_context *ctx);
+	bool (*search_next_nonblock)(struct mail_search_context *ctx,
+				     struct mail **mail_r, bool *tryagain_r);
+	/* Internally used by the search to find the next mail that potentially
+	   matches the search query. The function performs "quick checks" on
+	   the search query that can be done without initializing the mail
+	   struct. For example it can filter out non-matching mails based on
+	   SEARCH_SEQSET and SEARCH_UIDSET. Once a potentially matching mail is
+	   found, ctx->seq is updated to it.
+
+	   Plugins can use this function to skip over any mails that can't
+	   match the search query. Plugins can also set
+	   mail_search_arg.[non]match_always=TRUE
+	   for search args that it already definitely knows will/won't match,
+	   which prevents the standard search from attempting to match them
+	   again.
+
+	   This is used by the FTS plugin to skip over non-matching mails and
+	   to initialize the [non]match_always=TRUE for the search args that
+	   were matched against the FTS indexes. This prevents the standard
+	   search from having to open any email bodies. */
+	bool (*search_next_update_seq)(struct mail_search_context *ctx);
+	int (*search_next_match_mail)(struct mail_search_context *ctx,
+				      struct mail *mail);
+
+	struct mail_save_context *
+		(*save_alloc)(struct mailbox_transaction_context *t);
+	int (*save_begin)(struct mail_save_context *ctx, struct istream *input);
+	int (*save_continue)(struct mail_save_context *ctx);
+	int (*save_finish)(struct mail_save_context *ctx);
+	void (*save_cancel)(struct mail_save_context *ctx);
+	int (*copy)(struct mail_save_context *ctx, struct mail *mail);
+
+	/* Called during transaction commit/rollback if saving was done */
+	int (*transaction_save_commit_pre)(struct mail_save_context *save_ctx);
+	void (*transaction_save_commit_post)
+		(struct mail_save_context *save_ctx,
+		 struct mail_index_transaction_commit_result *result_r);
+	void (*transaction_save_rollback)(struct mail_save_context *save_ctx);
+
+	bool (*is_inconsistent)(struct mailbox *box);
+};
+
+union mailbox_module_context {
+        struct mailbox_vfuncs super;
+	struct mail_storage_module_register *reg;
+};
+
+struct mail_msgpart_partial_cache {
+	uint32_t uid;
+	uoff_t physical_start;
+	uoff_t physical_pos, virtual_pos;
+};
+
+struct mailbox_index_vsize {
+	uint64_t vsize;
+	uint32_t highest_uid;
+	uint32_t message_count;
+};
+
+struct mailbox_index_pop3_uidl {
+	uint32_t max_uid_with_pop3_uidl;
+};
+
+struct mailbox_index_first_saved {
+	uint32_t uid;
+	uint32_t timestamp;
+};
+
+struct mailbox {
+	const char *name;
+	/* mailbox's virtual name (from mail_namespace_get_vname()) */
+	const char *vname;
+	struct mail_storage *storage;
+	struct mailbox_list *list;
+	struct event *event;
+
+	struct mailbox_vfuncs v, *vlast;
+	/* virtual mailboxes: */
+	const struct virtual_mailbox_vfuncs *virtual_vfuncs;
+/* private: */
+	pool_t pool;
+	/* Linked list of all mailboxes in this storage */
+	struct mailbox *prev, *next;
+
+	/* these won't be set until mailbox is opened: */
+	struct mail_index *index;
+	struct mail_index_view *view;
+	struct mail_cache *cache;
+	/* Private per-user index/view for shared mailboxes. These are synced
+	   against the primary index and used to store per-user flags.
+	   These are non-NULL only when mailbox has per-user flags. */
+	struct mail_index *index_pvt;
+	struct mail_index_view *view_pvt;
+	/* Filled lazily by mailbox_get_permissions() */
+	struct mailbox_permissions _perm;
+	/* Filled lazily when mailbox is opened, use mailbox_get_path()
+	   to access it */
+	const char *_path;
+	/* Filled lazily when mailbox is opened, use mailbox_get_index_path()
+	   to access it */
+	const char *_index_path;
+
+	/* default vfuncs for new struct mails. */
+	const struct mail_vfuncs *mail_vfuncs;
+	/* Mailbox settings, or NULL if defaults */
+	const struct mailbox_settings *set;
+
+	/* If non-zero, fail mailbox_open() with this error. mailbox_alloc()
+	   can set this to force open to fail. */
+	enum mail_error open_error;
+
+	struct istream *input;
+	const char *index_prefix;
+	enum mailbox_flags flags;
+	unsigned int transaction_count;
+	unsigned int attribute_iter_count;
+	enum mailbox_feature enabled_features;
+	struct mail_msgpart_partial_cache partial_cache;
+	uint32_t vsize_hdr_ext_id;
+	uint32_t pop3_uidl_hdr_ext_id;
+	uint32_t box_name_hdr_ext_id;
+	uint32_t box_last_rename_stamp_ext_id;
+	uint32_t mail_vsize_ext_id;
+
+	/* MAIL_RECENT flags handling */
+	ARRAY_TYPE(seq_range) recent_flags;
+	uint32_t recent_flags_prev_uid;
+	uint32_t recent_flags_count;
+
+	struct mail_index_view *tmp_sync_view;
+
+	/* Mailbox notification settings: */
+	mailbox_notify_callback_t *notify_callback;
+	void *notify_context;
+	struct timeout *to_notify, *to_notify_delay;
+	struct mailbox_notify_file *notify_files;
+
+	/* Increased by one for each new struct mailbox. */
+	unsigned int generation_sequence;
+
+	/* Saved search results */
+	ARRAY(struct mail_search_result *) search_results;
+
+	/* Module-specific contexts. See mail_storage_module_id. */
+	ARRAY(union mailbox_module_context *) module_contexts;
+
+	/* When FAST open flag is used, the mailbox isn't actually opened until
+	   it's synced for the first time. */
+	bool opened:1;
+	/* Mailbox was deleted while we had it open. */
+	bool mailbox_deleted:1;
+	/* Mailbox is being created */
+	bool creating:1;
+	/* Mailbox is being deleted */
+	bool deleting:1;
+	/* Mailbox is being undeleted */
+	bool mailbox_undeleting:1;
+	/* Don't use MAIL_INDEX_SYNC_FLAG_DELETING_INDEX for sync flag */
+	bool delete_sync_check:1;
+	/* Delete mailbox only if it's empty */
+	bool deleting_must_be_empty:1;
+	/* The backend wants to skip checking if there are 0 messages before
+	   calling mailbox_list.delete_mailbox() */
+	bool delete_skip_empty_check:1;
+	/* Mailbox was already marked as deleted within this allocation. */
+	bool marked_deleted:1;
+	/* TRUE if this is an INBOX for this user */
+	bool inbox_user:1;
+	/* TRUE if this is an INBOX for this namespace (user or shared) */
+	bool inbox_any:1;
+	/* When copying to this mailbox, require that mailbox_copy() uses
+	   mailbox_save_*() to actually save a new physical copy rather than
+	   simply incrementing a reference count (e.g. via hard link) */
+	bool disable_reflink_copy_to:1;
+	/* Don't allow creating any new keywords */
+	bool disallow_new_keywords:1;
+	/* Mailbox has been synced at least once */
+	bool synced:1;
+	/* Updating cache file is disabled */
+	bool mail_cache_disabled:1;
+	/* Update first_saved field to mailbox list index. */
+	bool update_first_saved:1;
+	/* mailbox_verify_create_name() only checks for mailbox_verify_name() */
+	bool skip_create_name_restrictions:1;
+	/* Using LAYOUT=index and mailbox is being opened with a corrupted
+	   mailbox name. Try to revert to the previously known good name. */
+	bool corrupted_mailbox_name:1;
+	/* mailbox_open() returned MAIL_ERROR_NOTFOUND because the mailbox
+	   doesn't have the LOOKUP ACL right. */
+	bool acl_no_lookup_right:1;
+};
+
+struct mail_vfuncs {
+	void (*close)(struct mail *mail);
+	void (*free)(struct mail *mail);
+	void (*set_seq)(struct mail *mail, uint32_t seq, bool saving);
+	bool (*set_uid)(struct mail *mail, uint32_t uid);
+	void (*set_uid_cache_updates)(struct mail *mail, bool set);
+	bool (*prefetch)(struct mail *mail);
+	int (*precache)(struct mail *mail);
+	void (*add_temp_wanted_fields)(struct mail *mail,
+				       enum mail_fetch_field fields,
+				       struct mailbox_header_lookup_ctx *headers);
+
+	enum mail_flags (*get_flags)(struct mail *mail);
+	const char *const *(*get_keywords)(struct mail *mail);
+	const ARRAY_TYPE(keyword_indexes) *
+		(*get_keyword_indexes)(struct mail *mail);
+	uint64_t (*get_modseq)(struct mail *mail);
+	uint64_t (*get_pvt_modseq)(struct mail *mail);
+
+	int (*get_parts)(struct mail *mail,
+			 struct message_part **parts_r);
+	int (*get_date)(struct mail *mail, time_t *date_r, int *timezone_r);
+	int (*get_received_date)(struct mail *mail, time_t *date_r);
+	int (*get_save_date)(struct mail *mail, time_t *date_r);
+	int (*get_virtual_size)(struct mail *mail, uoff_t *size_r);
+	int (*get_physical_size)(struct mail *mail, uoff_t *size_r);
+
+	int (*get_first_header)(struct mail *mail, const char *field,
+				bool decode_to_utf8, const char **value_r);
+	int (*get_headers)(struct mail *mail, const char *field,
+			   bool decode_to_utf8, const char *const **value_r);
+	int (*get_header_stream)(struct mail *mail,
+				 struct mailbox_header_lookup_ctx *headers,
+				 struct istream **stream_r);
+	int (*get_stream)(struct mail *mail, bool get_body,
+			  struct message_size *hdr_size,
+			  struct message_size *body_size,
+			  struct istream **stream_r);
+	int (*get_binary_stream)(struct mail *mail,
+				 const struct message_part *part,
+				 bool include_hdr, uoff_t *size_r,
+				 unsigned int *lines_r, bool *binary_r,
+				 struct istream **stream_r);
+
+	int (*get_special)(struct mail *mail, enum mail_fetch_field field,
+			   const char **value_r);
+	int (*get_backend_mail)(struct mail *mail, struct mail **real_mail_r);
+
+	void (*update_flags)(struct mail *mail, enum modify_type modify_type,
+			     enum mail_flags flags);
+	void (*update_keywords)(struct mail *mail, enum modify_type modify_type,
+				struct mail_keywords *keywords);
+	void (*update_modseq)(struct mail *mail, uint64_t min_modseq);
+	void (*update_pvt_modseq)(struct mail *mail, uint64_t min_pvt_modseq);
+	void (*update_pop3_uidl)(struct mail *mail, const char *uidl);
+	void (*expunge)(struct mail *mail);
+	void (*set_cache_corrupted)(struct mail *mail,
+				    enum mail_fetch_field field,
+				    const char *reason);
+	int (*istream_opened)(struct mail *mail, struct istream **input);
+};
+
+union mail_module_context {
+	struct mail_vfuncs super;
+	struct mail_module_register *reg;
+};
+
+struct mail_private {
+	struct mail mail;
+	struct mail_vfuncs v, *vlast;
+	/* normally NULL, but in case this is a "backend mail" for a mail
+	   created by virtual storage, this points back to the original virtual
+	   mail. at least mailbox_copy() bypasses the virtual storage, so this
+	   allows mail_log plugin to log the copy operation using the original
+	   mailbox name. */
+	struct mail *vmail;
+	/* Event is created lazily. Use mail_event() to access it. */
+	struct event *_event;
+
+	uint32_t seq_pvt;
+
+	/* initial wanted fields/headers, set by mail_alloc(): */
+	enum mail_fetch_field wanted_fields;
+	struct mailbox_header_lookup_ctx *wanted_headers;
+
+	pool_t pool, data_pool;
+	ARRAY(union mail_module_context *) module_contexts;
+
+	const char *get_stream_reason;
+
+	bool autoexpunged:1;
+	/* mail created by mailbox_search_*() */
+	bool search_mail:1;
+};
+
+struct mailbox_list_context {
+	struct mail_storage *storage;
+	enum mailbox_list_flags flags;
+	bool failed;
+};
+
+union mailbox_transaction_module_context {
+	struct mail_storage_module_register *reg;
+};
+
+struct mailbox_transaction_stats {
+	unsigned long open_lookup_count;
+	unsigned long stat_lookup_count;
+	unsigned long fstat_lookup_count;
+	/* number of files we've opened and read */
+	unsigned long files_read_count;
+	/* number of bytes we've had to read from files */
+	unsigned long long files_read_bytes;
+	/* number of cache lookup hits */
+	unsigned long cache_hit_count;
+};
+
+struct mail_save_private_changes {
+	/* first saved mail is 0, second is 1, etc. we'll map these to UIDs
+	   using struct mail_transaction_commit_changes. */
+	unsigned int mailnum;
+	enum mail_flags flags;
+};
+
+struct mailbox_transaction_context {
+	struct mailbox *box;
+	enum mailbox_transaction_flags flags;
+	char *reason;
+
+	union mail_index_transaction_module_context module_ctx;
+	struct mail_index_transaction_vfuncs super;
+	int mail_ref_count;
+
+	struct mail_index_transaction *itrans;
+	struct dict_transaction_context *attr_pvt_trans, *attr_shared_trans;
+	/* view contains all changes done within this transaction */
+	struct mail_index_view *view;
+
+	/* for private index updates: */
+	struct mail_index_transaction *itrans_pvt;
+	struct mail_index_view *view_pvt;
+
+	struct mail_cache_view *cache_view;
+	struct mail_cache_transaction_ctx *cache_trans;
+
+	struct mail_transaction_commit_changes *changes;
+	ARRAY(union mailbox_transaction_module_context *) module_contexts;
+
+	uint32_t prev_pop3_uidl_tracking_seq;
+	uint32_t highest_pop3_uidl_uid;
+
+	struct mail_save_context *save_ctx;
+	/* number of mails saved/copied within this transaction. */
+	unsigned int save_count;
+	/* List of private flags added with save/copy. These are added to the
+	   private index after committing the mails to the shared index. */
+	ARRAY(struct mail_save_private_changes) pvt_saves;
+
+	/* these statistics are never reset by mail-storage API: */
+	struct mailbox_transaction_stats stats;
+	/* Set to TRUE to update stats_* fields */
+	bool stats_track:1;
+};
+
+union mail_search_module_context {
+	struct mail_storage_module_register *reg;
+};
+
+struct mail_search_context {
+	struct mailbox_transaction_context *transaction;
+
+	struct mail_search_args *args;
+	struct mail_search_sort_program *sort_program;
+	enum mail_fetch_field wanted_fields;
+	struct mailbox_header_lookup_ctx *wanted_headers;
+	normalizer_func_t *normalizer;
+
+	/* if non-NULL, specifies that a search resulting is being updated.
+	   this can be used as a search optimization: if searched message
+	   already exists in search result, it's not necessary to check if
+	   static data matches. */
+	struct mail_search_result *update_result;
+	/* add matches to these search results */
+	ARRAY(struct mail_search_result *) results;
+
+	uint32_t seq;
+	uint32_t progress_cur, progress_max;
+
+	ARRAY(struct mail *) mails;
+	unsigned int unused_mail_idx;
+	unsigned int max_mails;
+
+	ARRAY(union mail_search_module_context *) module_contexts;
+
+	bool seen_lost_data:1;
+	bool progress_hidden:1;
+};
+
+struct mail_save_data {
+	enum mail_flags flags;
+	enum mail_flags pvt_flags;
+	struct mail_keywords *keywords;
+	uint64_t min_modseq;
+
+	time_t received_date, save_date;
+	int received_tz_offset;
+
+	uint32_t uid;
+	char *guid, *pop3_uidl, *from_envelope;
+	uint32_t pop3_order;
+
+	struct ostream *output;
+	struct mail_save_attachment *attach;
+};
+
+struct mail_save_context {
+	struct mailbox_transaction_context *transaction;
+	struct mail *dest_mail;
+	/* Set during mailbox_copy(). This is useful when copying is
+	   implemented via save, and the save_*() methods want to access the
+	   source mail. */
+	struct mail *copy_src_mail;
+
+	/* data that changes for each saved mail */
+	struct mail_save_data data;
+
+	/* returns TRUE if message part is an attachment. */
+	bool (*part_is_attachment)(struct mail_save_context *ctx,
+				   const struct mail_attachment_part *part);
+
+	/* mailbox_save_alloc() called, but finish/cancel not.
+	   the same context is usually returned by the backends for reuse. */
+	bool unfinished:1;
+	/* mailbox_save_finish() or mailbox_copy() is being called. */
+	bool finishing:1;
+	/* mail was copied or moved using saving (requires:
+	   copying_or_moving==TRUE). */
+	bool copying_via_save:1;
+	/* mail is being saved, not copied. However, this is set also with
+	   mailbox_save_using_mail() and then copying_or_moving==TRUE. */
+	bool saving:1;
+	/* mail is being moved - ignore quota (requires:
+	   copying_or_moving==TRUE && saving==FALSE). */
+	bool moving:1;
+	/* mail is being copied or moved. However, this is set also with
+	   mailbox_save_using_mail() and then saving==TRUE. */
+	bool copying_or_moving:1;
+};
+
+struct mailbox_sync_context {
+	struct mailbox *box;
+	enum mailbox_sync_flags flags;
+	bool open_failed;
+};
+
+struct mailbox_header_lookup_ctx {
+	struct mailbox *box;
+	pool_t pool;
+	int refcount;
+
+	unsigned int count;
+	const char *const *name;
+	unsigned int *idx;
+};
+
+/* Modules should use do "my_id = mail_storage_module_id++" and
+   use objects' module_contexts[id] for their own purposes. */
+extern struct mail_storage_module_register mail_storage_module_register;
+
+/* Storage's module_id for mail_index. */
+extern struct mail_module_register mail_module_register;
+
+extern struct event_category event_category_storage;
+extern struct event_category event_category_mailbox;
+extern struct event_category event_category_mail;
+
+#define MAIL_STORAGE_CONTEXT(obj) \
+	MODULE_CONTEXT(obj, mail_storage_mail_index_module)
+#define MAIL_STORAGE_CONTEXT_REQUIRE(obj) \
+	MODULE_CONTEXT_REQUIRE(obj, mail_storage_mail_index_module)
+extern MODULE_CONTEXT_DEFINE(mail_storage_mail_index_module,
+			     &mail_index_module_register);
+
+void mail_storage_obj_ref(struct mail_storage *storage);
+void mail_storage_obj_unref(struct mail_storage *storage);
+
+/* Set error message in storage. Critical errors are logged with i_error(),
+   but user sees only "internal error" message. */
+void mail_storage_clear_error(struct mail_storage *storage);
+void mail_storage_set_error(struct mail_storage *storage,
+			    enum mail_error error, const char *string);
+void mail_storage_set_critical(struct mail_storage *storage,
+			       const char *fmt, ...) ATTR_FORMAT(2, 3);
+void mailbox_set_critical(struct mailbox *box,
+			  const char *fmt, ...) ATTR_FORMAT(2, 3);
+void mail_set_critical(struct mail *mail,
+		       const char *fmt, ...) ATTR_FORMAT(2, 3);
+void mail_storage_set_internal_error(struct mail_storage *storage);
+void mailbox_set_index_error(struct mailbox *box);
+void mail_storage_set_index_error(struct mail_storage *storage,
+				  struct mail_index *index);
+bool mail_storage_set_error_from_errno(struct mail_storage *storage);
+void mail_storage_copy_list_error(struct mail_storage *storage,
+				  struct mailbox_list *list);
+void mail_storage_copy_error(struct mail_storage *dest,
+			     struct mail_storage *src);
+/* set record in mail cache corrupted */
+void mail_set_mail_cache_corrupted(struct mail *mail, const char *fmt, ...)
+	ATTR_FORMAT(2, 3);
+
+/* Indicate mail being expunged by autoexpunge */
+void mail_autoexpunge(struct mail *mail);
+
+void mail_event_create(struct mail *mail);
+/* Returns TRUE if everything should already be in memory after this call
+   or if prefetching is not supported, i.e. the caller shouldn't do more
+   prefetching before this message is handled. */
+bool mail_prefetch(struct mail *mail);
+void mail_set_aborted(struct mail *mail);
+void mail_set_expunged(struct mail *mail);
+void mail_set_seq_saving(struct mail *mail, uint32_t seq);
+/* Returns true IF and only IF the mail has EITHER one of the
+   attachment keywords set. If it has both, or none, it will return FALSE. */
+bool mail_has_attachment_keywords(struct mail *mail);
+/* Sets attachment keywords. Returns -1 on error, 0 when no attachment(s) found,
+   and 1 if attachment was found. */
+int mail_set_attachment_keywords(struct mail *mail);
+
+/* Attempt to start accessing the mail stream. Returns TRUE is ok, FALSE if
+   prevented by mail->lookup_abort. */
+bool mail_stream_access_start(struct mail *mail);
+/* Attempt to start accessing the mail metadata. Returns TRUE is ok, FALSE if
+   prevented by mail->lookup_abort. */
+bool mail_metadata_access_start(struct mail *mail);
+/* Emit mail opened events */
+void mail_opened_event(struct mail *mail);
+
+/* Emit mail expunge_requested event */
+void mail_expunge_requested_event(struct mail *mail);
+
+void mailbox_set_deleted(struct mailbox *box);
+int mailbox_mark_index_deleted(struct mailbox *box, bool del);
+/* Easy wrapper for getting mailbox's MAILBOX_LIST_PATH_TYPE_MAILBOX.
+   The mailbox must already be opened and the caller must know that the
+   storage has mailbox files (i.e. NULL/empty path is never returned). */
+const char *mailbox_get_path(struct mailbox *box) ATTR_PURE;
+/* Similar to mailbox_get_path() but for MAILBOX_LIST_PATH_TYPE_INDEX. */
+const char *mailbox_get_index_path(struct mailbox *box) ATTR_PURE;
+/* Wrapper to mailbox_list_get_path() */
+int mailbox_get_path_to(struct mailbox *box, enum mailbox_list_path_type type,
+			const char **path_r);
+/* Get mailbox permissions. */
+const struct mailbox_permissions *mailbox_get_permissions(struct mailbox *box);
+/* Force permissions to be refreshed on next lookup */
+void mailbox_refresh_permissions(struct mailbox *box);
+
+/* Open private index files for mailbox. Returns 1 if opened, 0 if there
+   are no private indexes (or flags) in this mailbox, -1 if error. */
+int mailbox_open_index_pvt(struct mailbox *box);
+/* Create path's directory with proper permissions. The root directory is also
+   created if necessary. Returns 1 if created, 0 if it already existed,
+   -1 if error. */
+int mailbox_mkdir(struct mailbox *box, const char *path,
+		  enum mailbox_list_path_type type);
+/* Create a non-mailbox type directory for mailbox if it's missing (e.g. index).
+   Optimized for case where the directory usually exists. */
+int mailbox_create_missing_dir(struct mailbox *box,
+			       enum mailbox_list_path_type type);
+/* Returns TRUE if mailbox is autocreated. */
+bool mailbox_is_autocreated(struct mailbox *box);
+/* Returns TRUE if mailbox is autosubscribed. */
+bool mailbox_is_autosubscribed(struct mailbox *box);
+
+/* Returns -1 if error, 0 if failed with EEXIST, 1 if ok */
+int mailbox_create_fd(struct mailbox *box, const char *path, int flags,
+		      int *fd_r);
+/* Create a lock file with the given path and settings. If it succeeds,
+   returns 1 and lock_r, which needs to be freed once finished with the lock.
+   If lock_set->lock_timeout_secs is reached, returns 0 and error_r. Returns
+   -1 and sets error_r on other errors. */
+int mail_storage_lock_create(const char *lock_path,
+			     const struct file_create_settings *lock_set,
+			     const struct mail_storage_settings *mail_set,
+			     struct file_lock **lock_r, const char **error_r);
+/* Create a lock file to the mailbox with the given filename. Returns the same
+   as mail_storage_lock_create(). */
+int mailbox_lock_file_create(struct mailbox *box, const char *lock_fname,
+			     unsigned int lock_secs, struct file_lock **lock_r,
+			     const char **error_r);
+unsigned int mail_storage_get_lock_timeout(struct mail_storage *storage,
+					   unsigned int secs);
+void mail_storage_free_binary_cache(struct mail_storage *storage);
+
+enum mail_index_open_flags
+mail_storage_settings_to_index_flags(const struct mail_storage_settings *set);
+void mailbox_save_context_deinit(struct mail_save_context *ctx);
+
+/* Notify that a sync should be done. */
+void mailbox_sync_notify(struct mailbox *box, uint32_t uid,
+			 enum mailbox_sync_type sync_type);
+
+/* for unit testing */
+int mailbox_verify_name(struct mailbox *box);
+
+int mail_storage_list_index_rebuild_and_set_uncorrupted(struct mail_storage *storage);
+int mail_storage_list_index_rebuild(struct mail_storage *storage,
+				    enum mail_storage_list_index_rebuild_reason reason);
+
+#endif