dsync-brain.c revision 2d66fbf7a14d354cd7ffa3e504fc660a99f22f75
/* Copyright (c) 2013 Dovecot authors, see the included COPYING file */
#include "lib.h"
#include "array.h"
#include "hash.h"
#include "hostpid.h"
#include "mail-namespace.h"
#include "dsync-mailbox-tree.h"
#include "dsync-ibc.h"
#include "dsync-brain-private.h"
#include <sys/stat.h>
static const char *dsync_state_names[DSYNC_STATE_DONE+1] = {
"recv_handshake",
"send_last_common",
"recv_last_common",
"send_mailbox_tree",
"send_mailbox_tree_deletes",
"recv_mailbox_tree",
"recv_mailbox_tree_deletes",
"master_send_mailbox",
"slave_recv_mailbox",
"sync_mails",
"done"
};
static void dsync_brain_run_io(void *context)
{
struct dsync_brain *brain = context;
bool changed, try_pending;
if (dsync_ibc_has_failed(brain->ibc)) {
io_loop_stop(current_ioloop);
brain->failed = TRUE;
return;
}
try_pending = TRUE;
do {
if (!dsync_brain_run(brain, &changed)) {
io_loop_stop(current_ioloop);
break;
}
if (changed)
try_pending = TRUE;
else if (try_pending) {
if (dsync_ibc_has_pending_data(brain->ibc))
changed = TRUE;
try_pending = FALSE;
}
} while (changed);
}
static struct dsync_brain *
dsync_brain_common_init(struct mail_user *user, struct dsync_ibc *ibc)
{
struct dsync_brain *brain;
pool_t pool;
pool = pool_alloconly_create("dsync brain", 10240);
brain = p_new(pool, struct dsync_brain, 1);
brain->pool = pool;
brain->user = user;
brain->ibc = ibc;
brain->sync_type = DSYNC_BRAIN_SYNC_TYPE_UNKNOWN;
brain->lock_fd = -1;
hash_table_create(&brain->mailbox_states, pool, 0,
guid_128_hash, guid_128_cmp);
p_array_init(&brain->remote_mailbox_states, pool, 64);
return brain;
}
static void
dsync_brain_set_flags(struct dsync_brain *brain, enum dsync_brain_flags flags)
{
brain->mail_requests =
(flags & DSYNC_BRAIN_FLAG_SEND_MAIL_REQUESTS) != 0;
brain->backup_send = (flags & DSYNC_BRAIN_FLAG_BACKUP_SEND) != 0;
brain->backup_recv = (flags & DSYNC_BRAIN_FLAG_BACKUP_RECV) != 0;
brain->debug = (flags & DSYNC_BRAIN_FLAG_DEBUG) != 0;
brain->sync_visible_namespaces =
(flags & DSYNC_BRAIN_FLAG_SYNC_VISIBLE_NAMESPACES) != 0;
brain->no_mail_sync = (flags & DSYNC_BRAIN_FLAG_NO_MAIL_SYNC) != 0;
}
struct dsync_brain *
dsync_brain_master_init(struct mail_user *user, struct dsync_ibc *ibc,
struct mail_namespace *sync_ns, const char *sync_box,
const guid_128_t sync_box_guid,
enum dsync_brain_sync_type sync_type,
enum dsync_brain_flags flags, unsigned int lock_timeout,
const char *state)
{
struct dsync_ibc_settings ibc_set;
struct dsync_brain *brain;
const char *error;
i_assert(sync_type != DSYNC_BRAIN_SYNC_TYPE_UNKNOWN);
i_assert(sync_type != DSYNC_BRAIN_SYNC_TYPE_STATE || *state != '\0');
brain = dsync_brain_common_init(user, ibc);
brain->sync_type = sync_type;
if (sync_ns != NULL)
brain->sync_ns = sync_ns;
brain->sync_box = p_strdup(brain->pool, sync_box);
memcpy(brain->sync_box_guid, sync_box_guid, sizeof(brain->sync_box_guid));
brain->lock_timeout = lock_timeout;
brain->master_brain = TRUE;
dsync_brain_set_flags(brain, flags);
if (sync_type == DSYNC_BRAIN_SYNC_TYPE_STATE &&
dsync_mailbox_states_import(brain->mailbox_states,
brain->pool, state, &error) < 0) {
hash_table_clear(brain->mailbox_states, FALSE);
i_error("Saved sync state is invalid, "
"falling back to full sync: %s", error);
brain->sync_type = sync_type = DSYNC_BRAIN_SYNC_TYPE_FULL;
}
dsync_brain_mailbox_trees_init(brain);
memset(&ibc_set, 0, sizeof(ibc_set));
ibc_set.hostname = my_hostdomain();
ibc_set.sync_ns_prefix = sync_ns == NULL ? NULL : sync_ns->prefix;
ibc_set.sync_box = sync_box;
memcpy(ibc_set.sync_box_guid, sync_box_guid,
sizeof(ibc_set.sync_box_guid));
ibc_set.sync_type = sync_type;
ibc_set.lock_timeout = lock_timeout;
/* reverse the backup direction for the slave */
ibc_set.brain_flags = flags & ~(DSYNC_BRAIN_FLAG_BACKUP_SEND |
DSYNC_BRAIN_FLAG_BACKUP_RECV);
if ((flags & DSYNC_BRAIN_FLAG_BACKUP_SEND) != 0)
ibc_set.brain_flags |= DSYNC_BRAIN_FLAG_BACKUP_RECV;
else if ((flags & DSYNC_BRAIN_FLAG_BACKUP_RECV) != 0)
ibc_set.brain_flags |= DSYNC_BRAIN_FLAG_BACKUP_SEND;
dsync_ibc_send_handshake(ibc, &ibc_set);
dsync_ibc_set_io_callback(ibc, dsync_brain_run_io, brain);
brain->state = DSYNC_STATE_MASTER_RECV_HANDSHAKE;
return brain;
}
struct dsync_brain *
dsync_brain_slave_init(struct mail_user *user, struct dsync_ibc *ibc)
{
struct dsync_ibc_settings ibc_set;
struct dsync_brain *brain;
brain = dsync_brain_common_init(user, ibc);
brain->state = DSYNC_STATE_SLAVE_RECV_HANDSHAKE;
memset(&ibc_set, 0, sizeof(ibc_set));
ibc_set.hostname = my_hostdomain();
dsync_ibc_send_handshake(ibc, &ibc_set);
dsync_ibc_set_io_callback(ibc, dsync_brain_run_io, brain);
return brain;
}
int dsync_brain_deinit(struct dsync_brain **_brain)
{
struct dsync_brain *brain = *_brain;
int ret;
*_brain = NULL;
if (dsync_ibc_has_timed_out(brain->ibc)) {
i_error("Timeout during state=%s%s",
dsync_state_names[brain->state],
brain->state != DSYNC_STATE_SYNC_MAILS ? "" :
t_strdup_printf(" (send=%s recv=%s)",
dsync_box_state_names[brain->box_send_state],
dsync_box_state_names[brain->box_recv_state]));
}
if (dsync_ibc_has_failed(brain->ibc) ||
brain->state != DSYNC_STATE_DONE)
brain->failed = TRUE;
dsync_ibc_close_mail_streams(brain->ibc);
if (brain->box != NULL)
dsync_brain_sync_mailbox_deinit(brain);
if (brain->local_tree_iter != NULL)
dsync_mailbox_tree_iter_deinit(&brain->local_tree_iter);
if (brain->mailbox_states_iter != NULL)
hash_table_iterate_deinit(&brain->mailbox_states_iter);
hash_table_destroy(&brain->mailbox_states);
if (brain->lock_fd != -1) {
/* unlink the lock file before it gets unlocked */
if (unlink(brain->lock_path) < 0)
i_error("unlink(%s) failed: %m", brain->lock_path);
file_lock_free(&brain->lock);
i_close_fd(&brain->lock_fd);
}
ret = brain->failed ? -1 : 0;
pool_unref(&brain->pool);
return ret;
}
static int
dsync_brain_lock(struct dsync_brain *brain, const char *remote_hostname)
{
struct stat st1, st2;
const char *home;
int ret;
if ((ret = strcmp(remote_hostname, my_hostdomain())) < 0) {
/* locking done by remote */
return 0;
}
if (ret == 0 && !brain->master_brain) {
/* running dsync within the same server.
locking done by master brain. */
return 0;
}
if ((ret = mail_user_get_home(brain->user, &home)) < 0) {
i_error("Couldn't look up user's home dir");
return -1;
}
if (ret == 0) {
i_error("User has no home directory");
return -1;
}
brain->lock_path = p_strconcat(brain->pool, home,
"/"DSYNC_LOCK_FILENAME, NULL);
for (;;) {
brain->lock_fd = creat(brain->lock_path, 0600);
if (brain->lock_fd == -1) {
i_error("Couldn't create lock %s: %m",
brain->lock_path);
return -1;
}
if (file_wait_lock(brain->lock_fd, brain->lock_path, F_WRLCK,
FILE_LOCK_METHOD_FCNTL, brain->lock_timeout,
&brain->lock) <= 0) {
if (errno == EAGAIN) {
i_error("Couldn't lock %s: Timed out after %u seconds",
brain->lock_path, brain->lock_timeout);
} else {
i_error("Couldn't lock %s: %m", brain->lock_path);
}
break;
}
if (fstat(brain->lock_fd, &st1) < 0) {
if (errno != ESTALE) {
i_error("fstat(%s) failed: %m", brain->lock_path);
break;
}
} else if (stat(brain->lock_path, &st2) < 0) {
if (errno != ENOENT) {
i_error("stat(%s) failed: %m", brain->lock_path);
break;
}
} else if (st1.st_ino == st2.st_ino) {
/* success */
return 0;
}
/* file was recreated, try again */
i_close_fd(&brain->lock_fd);
}
i_close_fd(&brain->lock_fd);
return -1;
}
static bool dsync_brain_master_recv_handshake(struct dsync_brain *brain)
{
const struct dsync_ibc_settings *ibc_set;
i_assert(brain->master_brain);
if (dsync_ibc_recv_handshake(brain->ibc, &ibc_set) == 0)
return FALSE;
if (brain->lock_timeout > 0) {
if (dsync_brain_lock(brain, ibc_set->hostname) < 0) {
brain->failed = TRUE;
return FALSE;
}
}
brain->state = brain->sync_type == DSYNC_BRAIN_SYNC_TYPE_STATE ?
DSYNC_STATE_MASTER_SEND_LAST_COMMON :
DSYNC_STATE_SEND_MAILBOX_TREE;
return TRUE;
}
static bool dsync_brain_slave_recv_handshake(struct dsync_brain *brain)
{
const struct dsync_ibc_settings *ibc_set;
i_assert(!brain->master_brain);
if (dsync_ibc_recv_handshake(brain->ibc, &ibc_set) == 0)
return FALSE;
if (ibc_set->lock_timeout > 0) {
brain->lock_timeout = ibc_set->lock_timeout;
if (dsync_brain_lock(brain, ibc_set->hostname) < 0) {
brain->failed = TRUE;
return FALSE;
}
}
if (ibc_set->sync_ns_prefix != NULL) {
brain->sync_ns = mail_namespace_find(brain->user->namespaces,
ibc_set->sync_ns_prefix);
}
brain->sync_box = p_strdup(brain->pool, ibc_set->sync_box);
memcpy(brain->sync_box_guid, ibc_set->sync_box_guid,
sizeof(brain->sync_box_guid));
i_assert(brain->sync_type == DSYNC_BRAIN_SYNC_TYPE_UNKNOWN);
brain->sync_type = ibc_set->sync_type;
dsync_brain_set_flags(brain, ibc_set->brain_flags);
dsync_brain_mailbox_trees_init(brain);
if (brain->sync_type == DSYNC_BRAIN_SYNC_TYPE_STATE)
brain->state = DSYNC_STATE_SLAVE_RECV_LAST_COMMON;
else
brain->state = DSYNC_STATE_SEND_MAILBOX_TREE;
return TRUE;
}
static void dsync_brain_master_send_last_common(struct dsync_brain *brain)
{
struct dsync_mailbox_state *state;
uint8_t *guid;
enum dsync_ibc_send_ret ret = DSYNC_IBC_SEND_RET_OK;
i_assert(brain->master_brain);
if (brain->mailbox_states_iter == NULL) {
brain->mailbox_states_iter =
hash_table_iterate_init(brain->mailbox_states);
}
for (;;) {
if (ret == DSYNC_IBC_SEND_RET_FULL)
return;
if (!hash_table_iterate(brain->mailbox_states_iter,
brain->mailbox_states, &guid, &state))
break;
ret = dsync_ibc_send_mailbox_state(brain->ibc, state);
}
hash_table_iterate_deinit(&brain->mailbox_states_iter);
dsync_ibc_send_end_of_list(brain->ibc, DSYNC_IBC_EOL_MAILBOX_STATE);
brain->state = DSYNC_STATE_SEND_MAILBOX_TREE;
}
static void dsync_mailbox_state_add(struct dsync_brain *brain,
const struct dsync_mailbox_state *state)
{
struct dsync_mailbox_state *dupstate;
uint8_t *guid_p;
dupstate = p_new(brain->pool, struct dsync_mailbox_state, 1);
*dupstate = *state;
guid_p = dupstate->mailbox_guid;
hash_table_insert(brain->mailbox_states, guid_p, dupstate);
}
static bool dsync_brain_slave_recv_last_common(struct dsync_brain *brain)
{
struct dsync_mailbox_state state;
enum dsync_ibc_recv_ret ret;
bool changed = FALSE;
i_assert(!brain->master_brain);
while ((ret = dsync_ibc_recv_mailbox_state(brain->ibc, &state)) > 0) {
dsync_mailbox_state_add(brain, &state);
changed = TRUE;
}
if (ret == DSYNC_IBC_RECV_RET_FINISHED) {
brain->state = DSYNC_STATE_SEND_MAILBOX_TREE;
changed = TRUE;
}
return changed;
}
static bool dsync_brain_run_real(struct dsync_brain *brain, bool *changed_r)
{
bool changed = FALSE, ret = TRUE;
if (brain->failed)
return FALSE;
if (brain->debug) {
i_debug("brain %c: in state=%s", brain->master_brain ? 'M' : 'S',
dsync_state_names[brain->state]);
}
switch (brain->state) {
case DSYNC_STATE_MASTER_RECV_HANDSHAKE:
changed = dsync_brain_master_recv_handshake(brain);
break;
case DSYNC_STATE_SLAVE_RECV_HANDSHAKE:
changed = dsync_brain_slave_recv_handshake(brain);
break;
case DSYNC_STATE_MASTER_SEND_LAST_COMMON:
dsync_brain_master_send_last_common(brain);
changed = TRUE;
break;
case DSYNC_STATE_SLAVE_RECV_LAST_COMMON:
changed = dsync_brain_slave_recv_last_common(brain);
break;
case DSYNC_STATE_SEND_MAILBOX_TREE:
dsync_brain_send_mailbox_tree(brain);
changed = TRUE;
break;
case DSYNC_STATE_RECV_MAILBOX_TREE:
changed = dsync_brain_recv_mailbox_tree(brain);
break;
case DSYNC_STATE_SEND_MAILBOX_TREE_DELETES:
dsync_brain_send_mailbox_tree_deletes(brain);
changed = TRUE;
break;
case DSYNC_STATE_RECV_MAILBOX_TREE_DELETES:
changed = dsync_brain_recv_mailbox_tree_deletes(brain);
break;
case DSYNC_STATE_MASTER_SEND_MAILBOX:
dsync_brain_master_send_mailbox(brain);
changed = TRUE;
break;
case DSYNC_STATE_SLAVE_RECV_MAILBOX:
changed = dsync_brain_slave_recv_mailbox(brain);
break;
case DSYNC_STATE_SYNC_MAILS:
changed = dsync_brain_sync_mails(brain);
break;
case DSYNC_STATE_DONE:
changed = TRUE;
ret = FALSE;
break;
}
if (brain->debug) {
i_debug("brain %c: out state=%s changed=%d",
brain->master_brain ? 'M' : 'S',
dsync_state_names[brain->state], changed);
}
*changed_r = changed;
return brain->failed ? FALSE : ret;
}
bool dsync_brain_run(struct dsync_brain *brain, bool *changed_r)
{
bool ret;
*changed_r = FALSE;
if (dsync_ibc_has_failed(brain->ibc)) {
brain->failed = TRUE;
return FALSE;
}
T_BEGIN {
ret = dsync_brain_run_real(brain, changed_r);
} T_END;
return ret;
}
void dsync_brain_get_state(struct dsync_brain *brain, string_t *output)
{
struct hash_iterate_context *iter;
struct dsync_mailbox_node *node;
const struct dsync_mailbox_state *new_state;
struct dsync_mailbox_state *state;
const uint8_t *guid_p;
uint8_t *guid;
/* update mailbox states */
array_foreach(&brain->remote_mailbox_states, new_state) {
guid_p = new_state->mailbox_guid;
state = hash_table_lookup(brain->mailbox_states, guid_p);
if (state != NULL)
*state = *new_state;
else
dsync_mailbox_state_add(brain, new_state);
}
/* remove nonexistent mailboxes */
iter = hash_table_iterate_init(brain->mailbox_states);
while (hash_table_iterate(iter, brain->mailbox_states, &guid, &state)) {
node = dsync_mailbox_tree_lookup_guid(brain->local_mailbox_tree,
guid);
if (node == NULL ||
node->existence != DSYNC_MAILBOX_NODE_EXISTS)
hash_table_remove(brain->mailbox_states, guid);
}
hash_table_iterate_deinit(&iter);
dsync_mailbox_states_export(brain->mailbox_states, output);
}
bool dsync_brain_has_failed(struct dsync_brain *brain)
{
return brain->failed;
}