mail-transaction-log-file.c revision d9fda7e3a0fa5551547ac3e3054b837fc77f4bfb
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch/* Copyright (c) 2003-2010 Dovecot authors, see the included COPYING file */
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "lib.h"
9f8559a5ac7b53b83378c894de6578773dc1e392Timo Sirainen#include "ioloop.h"
9f8559a5ac7b53b83378c894de6578773dc1e392Timo Sirainen#include "buffer.h"
e641c9f656f1788ca6226ef0d60b2d592e2ca6d1Stephan Bosch#include "file-dotlock.h"
e641c9f656f1788ca6226ef0d60b2d592e2ca6d1Stephan Bosch#include "nfs-workarounds.h"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "read-full.h"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "write-full.h"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "mmap-util.h"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "mail-index-private.h"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "mail-index-modseq.h"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch#include "mail-transaction-log-private.h"
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch#define LOG_PREFETCH IO_BLOCK_SIZE
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch#define MEMORY_LOG_NAME "(in-memory transaction log file)"
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch#define LOG_NEW_DOTLOCK_SUFFIX ".newlock"
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Boschstatic int
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Boschlog_file_set_syscall_error(struct mail_transaction_log_file *file,
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch const char *function)
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch{
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch return mail_index_file_set_syscall_error(file->log->index,
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch file->filepath, function);
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch}
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Boschstatic void
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Boschmail_transaction_log_mark_corrupted(struct mail_transaction_log_file *file)
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch{
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch unsigned int offset =
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch offsetof(struct mail_transaction_log_header, indexid);
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch if (MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file) ||
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch file->log->index->readonly)
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch return;
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch /* indexid=0 marks the log file as corrupted */
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch if (pwrite_full(file->fd, &file->hdr.indexid,
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch sizeof(file->hdr.indexid), offset) < 0) {
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch mail_index_file_set_syscall_error(file->log->index,
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch file->filepath, "pwrite()");
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch }
1e653c7406ec0b062c0bacfdf2e7568a3f860500Stephan Bosch}
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Boschvoid
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Boschmail_transaction_log_file_set_corrupted(struct mail_transaction_log_file *file,
d45ab3fff7c47f1719b9cd310228c0dac2bdd1b2Timo Sirainen const char *fmt, ...)
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch{
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch va_list va;
e641c9f656f1788ca6226ef0d60b2d592e2ca6d1Stephan Bosch
e641c9f656f1788ca6226ef0d60b2d592e2ca6d1Stephan Bosch file->corrupted = TRUE;
e641c9f656f1788ca6226ef0d60b2d592e2ca6d1Stephan Bosch file->hdr.indexid = 0;
e641c9f656f1788ca6226ef0d60b2d592e2ca6d1Stephan Bosch mail_transaction_log_mark_corrupted(file);
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch va_start(va, fmt);
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch T_BEGIN {
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch mail_index_set_error(file->log->index,
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch "Corrupted transaction log file %s seq %u: %s "
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch "(sync_offset=%"PRIuUOFF_T")",
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch file->filepath, file->hdr.file_seq,
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch t_strdup_vprintf(fmt, va), file->sync_offset);
92c2272787b74eb000f05a926e9103a25a6a0dc0Stephan Bosch } T_END;
92c2272787b74eb000f05a926e9103a25a6a0dc0Stephan Bosch va_end(va);
92c2272787b74eb000f05a926e9103a25a6a0dc0Stephan Bosch}
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch
92c2272787b74eb000f05a926e9103a25a6a0dc0Stephan Boschstruct mail_transaction_log_file *
92c2272787b74eb000f05a926e9103a25a6a0dc0Stephan Boschmail_transaction_log_file_alloc(struct mail_transaction_log *log,
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch const char *path)
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch{
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch struct mail_transaction_log_file *file;
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch file = i_new(struct mail_transaction_log_file, 1);
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch file->log = log;
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch file->filepath = i_strdup(path);
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch file->fd = -1;
d82ad7143c057c565e1fd5f3580645556ed0bcc9Stephan Bosch return file;
069def4dc35022852d569b7ab75a3b19d2cb0f1cTimo Sirainen}
069def4dc35022852d569b7ab75a3b19d2cb0f1cTimo Sirainen
a952a4444e46e107b15ab1bd0e8b63a29f94b123Timo Sirainenvoid mail_transaction_log_file_free(struct mail_transaction_log_file **_file)
c911297407bdcc7c7936305eb8f791b450d6375cTimo Sirainen{
c911297407bdcc7c7936305eb8f791b450d6375cTimo Sirainen struct mail_transaction_log_file *file = *_file;
5394bed8aaef2a6c1c870a34a23a7824e1f370bbStephan Bosch struct mail_transaction_log_file **p;
int old_errno = errno;
*_file = NULL;
mail_transaction_log_file_unlock(file);
for (p = &file->log->files; *p != NULL; p = &(*p)->next) {
if (*p == file) {
*p = file->next;
break;
}
}
if (file == file->log->head)
file->log->head = NULL;
if (file->buffer != NULL)
buffer_free(&file->buffer);
if (file->mmap_base != NULL) {
if (munmap(file->mmap_base, file->mmap_size) < 0)
log_file_set_syscall_error(file, "munmap()");
}
if (file->fd != -1) {
if (close(file->fd) < 0)
log_file_set_syscall_error(file, "close()");
}
i_free(file->filepath);
i_free(file);
errno = old_errno;
}
static void
mail_transaction_log_file_skip_to_head(struct mail_transaction_log_file *file)
{
struct mail_transaction_log *log = file->log;
struct mail_index_map *map = log->index->map;
const struct mail_index_modseq_header *modseq_hdr;
uoff_t head_offset;
if (map == NULL || file->hdr.file_seq != map->hdr.log_file_seq ||
map->hdr.log_file_head_offset == 0)
return;
/* we can get a valid log offset from index file. initialize
sync_offset from it so we don't have to read the whole log
file from beginning. */
head_offset = map->hdr.log_file_head_offset;
modseq_hdr = mail_index_map_get_modseq_header(map);
if (head_offset < file->hdr.hdr_size) {
mail_index_set_error(log->index,
"%s: log_file_head_offset too small",
log->index->filepath);
file->sync_offset = file->hdr.hdr_size;
file->sync_highest_modseq = file->hdr.initial_modseq;
} else if (modseq_hdr == NULL && file->hdr.initial_modseq == 0) {
/* modseqs not used yet */
file->sync_offset = head_offset;
file->sync_highest_modseq = 0;
} else if (modseq_hdr == NULL ||
modseq_hdr->log_seq != file->hdr.file_seq) {
/* highest_modseq not synced, start from beginning */
file->sync_offset = file->hdr.hdr_size;
file->sync_highest_modseq = file->hdr.initial_modseq;
} else if (modseq_hdr->log_offset > head_offset) {
mail_index_set_error(log->index,
"%s: modseq_hdr.log_offset too large",
log->index->filepath);
file->sync_offset = file->hdr.hdr_size;
file->sync_highest_modseq = file->hdr.initial_modseq;
} else {
/* start from where we last stopped tracking modseqs */
file->sync_offset = modseq_hdr->log_offset;
file->sync_highest_modseq = modseq_hdr->highest_modseq;
}
if (file->hdr.file_seq == log->index->map->hdr.log_file_seq) {
file->saved_tail_offset =
log->index->map->hdr.log_file_tail_offset;
file->saved_tail_sync_offset = file->saved_tail_offset;
}
if (file->saved_tail_offset > file->max_tail_offset)
file->max_tail_offset = file->saved_tail_offset;
}
static void
mail_transaction_log_file_add_to_list(struct mail_transaction_log_file *file)
{
struct mail_transaction_log_file **p;
file->sync_offset = file->hdr.hdr_size;
file->sync_highest_modseq = file->hdr.initial_modseq;
mail_transaction_log_file_skip_to_head(file);
/* insert it to correct position */
for (p = &file->log->files; *p != NULL; p = &(*p)->next) {
if ((*p)->hdr.file_seq > file->hdr.file_seq)
break;
i_assert((*p)->hdr.file_seq < file->hdr.file_seq);
}
file->next = *p;
*p = file;
}
static int
mail_transaction_log_init_hdr(struct mail_transaction_log *log,
struct mail_transaction_log_header *hdr)
{
struct mail_index *index = log->index;
struct mail_transaction_log_file *file;
memset(hdr, 0, sizeof(*hdr));
hdr->major_version = MAIL_TRANSACTION_LOG_MAJOR_VERSION;
hdr->minor_version = MAIL_TRANSACTION_LOG_MINOR_VERSION;
hdr->hdr_size = sizeof(struct mail_transaction_log_header);
hdr->indexid = log->index->indexid;
hdr->create_stamp = ioloop_time;
#if !WORDS_BIGENDIAN
hdr->compat_flags |= MAIL_INDEX_COMPAT_LITTLE_ENDIAN;
#endif
if (index->fd != -1) {
/* not creating index - make sure we have latest header */
if (!index->mapping) {
if (mail_index_map(index,
MAIL_INDEX_SYNC_HANDLER_HEAD) <= 0)
return -1;
} else {
/* if we got here from mapping, the .log file is
corrupted. use whatever values we got from index
file */
}
}
if (index->map != NULL) {
hdr->prev_file_seq = index->map->hdr.log_file_seq;
hdr->prev_file_offset = index->map->hdr.log_file_head_offset;
hdr->file_seq = index->map->hdr.log_file_seq + 1;
hdr->initial_modseq =
mail_index_map_modseq_get_highest(index->map);
} else {
hdr->file_seq = 1;
}
if (log->head != NULL) {
/* make sure the sequence always increases to avoid crashes
later. this catches the buggy case where two processes
happen to replace the same log file. */
for (file = log->head->next; file != NULL; file = file->next) {
if (hdr->file_seq <= file->hdr.file_seq)
hdr->file_seq = file->hdr.file_seq + 1;
}
if (hdr->file_seq <= log->head->hdr.file_seq) {
/* make sure the sequence grows */
hdr->file_seq = log->head->hdr.file_seq+1;
}
if (hdr->initial_modseq < log->head->sync_highest_modseq) {
/* this should be always up-to-date */
hdr->initial_modseq = log->head->sync_highest_modseq;
}
}
return 0;
}
struct mail_transaction_log_file *
mail_transaction_log_file_alloc_in_memory(struct mail_transaction_log *log)
{
struct mail_transaction_log_file *file;
file = mail_transaction_log_file_alloc(log, MEMORY_LOG_NAME);
if (mail_transaction_log_init_hdr(log, &file->hdr) < 0) {
i_free(file);
return NULL;
}
file->buffer = buffer_create_dynamic(default_pool, 4096);
file->buffer_offset = sizeof(file->hdr);
mail_transaction_log_file_add_to_list(file);
return file;
}
static int
mail_transaction_log_file_dotlock(struct mail_transaction_log_file *file)
{
struct dotlock_settings dotlock_set;
int ret;
if (file->log->dotlock_count > 0)
ret = 1;
else {
mail_transaction_log_get_dotlock_set(file->log, &dotlock_set);
ret = file_dotlock_create(&dotlock_set, file->filepath, 0,
&file->log->dotlock);
}
if (ret > 0) {
file->log->dotlock_count++;
file->locked = TRUE;
file->lock_created = time(NULL);
return 0;
}
if (ret < 0) {
log_file_set_syscall_error(file, "file_dotlock_create()");
return -1;
}
mail_index_set_error(file->log->index,
"Timeout (%us) while waiting for "
"dotlock for transaction log file %s",
dotlock_set.timeout, file->filepath);
file->log->index->index_lock_timeout = TRUE;
return -1;
}
static int
mail_transaction_log_file_undotlock(struct mail_transaction_log_file *file)
{
int ret;
if (--file->log->dotlock_count > 0)
return 0;
ret = file_dotlock_delete(&file->log->dotlock);
if (ret < 0) {
log_file_set_syscall_error(file, "file_dotlock_delete()");
return -1;
}
if (ret == 0) {
mail_index_set_error(file->log->index,
"Dotlock was lost for transaction log file %s",
file->filepath);
return -1;
}
return 0;
}
int mail_transaction_log_file_lock(struct mail_transaction_log_file *file)
{
unsigned int lock_timeout_secs;
int ret;
if (file->locked)
return 0;
if (MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file)) {
file->locked = TRUE;
return 0;
}
if (file->log->index->lock_method == FILE_LOCK_METHOD_DOTLOCK)
return mail_transaction_log_file_dotlock(file);
i_assert(file->file_lock == NULL);
lock_timeout_secs = I_MIN(MAIL_TRANSCATION_LOG_LOCK_TIMEOUT,
file->log->index->max_lock_timeout_secs);
ret = mail_index_lock_fd(file->log->index, file->filepath, file->fd,
F_WRLCK, lock_timeout_secs,
&file->file_lock);
if (ret > 0) {
file->locked = TRUE;
file->lock_created = time(NULL);
return 0;
}
if (ret < 0) {
log_file_set_syscall_error(file, "mail_index_wait_lock_fd()");
return -1;
}
mail_index_set_error(file->log->index,
"Timeout (%us) while waiting for lock for "
"transaction log file %s",
lock_timeout_secs, file->filepath);
file->log->index->index_lock_timeout = TRUE;
return -1;
}
void mail_transaction_log_file_unlock(struct mail_transaction_log_file *file)
{
unsigned int lock_time;
if (!file->locked)
return;
file->locked = FALSE;
if (MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file))
return;
lock_time = time(NULL) - file->lock_created;
if (lock_time >= MAIL_TRANSCATION_LOG_LOCK_TIMEOUT) {
i_warning("Transaction log file %s was locked for %u seconds",
file->filepath, lock_time);
}
if (file->log->index->lock_method == FILE_LOCK_METHOD_DOTLOCK) {
mail_transaction_log_file_undotlock(file);
return;
}
file_unlock(&file->file_lock);
}
static ssize_t
mail_transaction_log_file_read_header(struct mail_transaction_log_file *file)
{
ssize_t pos, ret;
memset(&file->hdr, 0, sizeof(file->hdr));
/* try to read the whole header, but it's not necessarily an error to
read less since the older versions of the log format could be
smaller. */
pos = 0;
do {
ret = pread(file->fd, PTR_OFFSET(&file->hdr, pos),
sizeof(file->hdr) - pos, pos);
if (ret > 0)
pos += ret;
} while (ret > 0 && pos < (ssize_t)sizeof(file->hdr));
return ret < 0 ? -1 : pos;
}
static int
mail_transaction_log_file_read_hdr(struct mail_transaction_log_file *file,
bool ignore_estale)
{
struct mail_transaction_log_file *f;
int ret;
i_assert(!MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file));
if (file->corrupted)
return 0;
ret = mail_transaction_log_file_read_header(file);
if (ret < 0) {
if (errno != ESTALE || !ignore_estale)
log_file_set_syscall_error(file, "pread()");
return -1;
}
if (file->hdr.major_version != MAIL_TRANSACTION_LOG_MAJOR_VERSION) {
/* incompatible version - fix silently */
return 0;
}
if (ret < MAIL_TRANSACTION_LOG_HEADER_MIN_SIZE) {
mail_transaction_log_file_set_corrupted(file,
"unexpected end of file while reading header");
return 0;
}
if (file->hdr.minor_version >= 2 || file->hdr.major_version > 1) {
/* we have compatibility flags */
enum mail_index_header_compat_flags compat_flags = 0;
#if !WORDS_BIGENDIAN
compat_flags |= MAIL_INDEX_COMPAT_LITTLE_ENDIAN;
#endif
if (file->hdr.compat_flags != compat_flags) {
/* architecture change */
mail_index_set_error(file->log->index,
"Rebuilding index file %s: "
"CPU architecture changed",
file->log->index->filepath);
return 0;
}
}
if (file->hdr.hdr_size < MAIL_TRANSACTION_LOG_HEADER_MIN_SIZE) {
mail_transaction_log_file_set_corrupted(file,
"Header size too small");
return 0;
}
if (file->hdr.hdr_size < sizeof(file->hdr)) {
/* @UNSAFE: smaller than we expected - zero out the fields we
shouldn't have filled */
memset(PTR_OFFSET(&file->hdr, file->hdr.hdr_size), 0,
sizeof(file->hdr) - file->hdr.hdr_size);
}
if (file->hdr.indexid == 0) {
/* corrupted */
file->corrupted = TRUE;
mail_index_set_error(file->log->index,
"Transaction log file %s: marked corrupted",
file->filepath);
return 0;
}
if (file->hdr.indexid != file->log->index->indexid) {
if (file->log->index->indexid != 0 &&
!file->log->index->initial_create) {
/* index file was probably just rebuilt and we don't
know about it yet */
mail_transaction_log_file_set_corrupted(file,
"indexid changed %u -> %u",
file->log->index->indexid, file->hdr.indexid);
return 0;
}
/* creating index file. since transaction log is created
first, use the indexid in it to create the main index
to avoid races. */
file->log->index->indexid = file->hdr.indexid;
}
/* make sure we already don't have a file with the same sequence
opened. it shouldn't happen unless the old log file was
corrupted. */
for (f = file->log->files; f != NULL; f = f->next) {
if (f->hdr.file_seq == file->hdr.file_seq) {
/* mark the old file corrupted. we can't safely remove
it from the list however, so return failure. */
f->corrupted = TRUE;
f->hdr.indexid = 0;
if (strcmp(f->filepath, f->log->head->filepath) != 0) {
/* only mark .2 corrupted, just to make sure
we don't lose any changes from .log in case
we're somehow wrong */
mail_transaction_log_mark_corrupted(f);
ret = 0;
} else {
ret = -1;
}
mail_index_set_error(f->log->index,
"Transaction log %s: "
"duplicate transaction log sequence (%u)",
f->filepath, f->hdr.file_seq);
return ret;
}
}
file->sync_highest_modseq = file->hdr.initial_modseq;
return 1;
}
static int
mail_transaction_log_file_stat(struct mail_transaction_log_file *file,
bool ignore_estale)
{
struct stat st;
if (fstat(file->fd, &st) < 0) {
if (errno != ESTALE || !ignore_estale)
log_file_set_syscall_error(file, "fstat()");
return -1;
}
file->st_dev = st.st_dev;
file->st_ino = st.st_ino;
file->last_mtime = st.st_mtime;
file->last_size = st.st_size;
return 0;
}
static bool
mail_transaction_log_file_is_dupe(struct mail_transaction_log_file *file)
{
struct mail_transaction_log_file *tmp;
for (tmp = file->log->files; tmp != NULL; tmp = tmp->next) {
if (tmp->st_ino == file->st_ino &&
CMP_DEV_T(tmp->st_dev, file->st_dev))
return TRUE;
}
return FALSE;
}
static int
mail_transaction_log_file_create2(struct mail_transaction_log_file *file,
int new_fd, bool reset,
struct dotlock **dotlock)
{
struct mail_index *index = file->log->index;
struct stat st;
const char *path2;
int fd, ret;
bool rename_existing;
if (file->log->nfs_flush) {
/* although we check also mtime and file size below, it's done
only to fix broken log files. we don't bother flushing
attribute cache just for that. */
nfs_flush_file_handle_cache(file->filepath);
}
/* log creation is locked now - see if someone already created it.
note that if we're rotating, we need to keep the log locked until
the file has been rewritten. and because fcntl() locks are stupid,
if we go and open()+close() the file and we had it already opened,
its locks are lost. so we use stat() to check if the file has been
recreated, although it almost never is. */
if (reset)
rename_existing = FALSE;
else if (nfs_safe_stat(file->filepath, &st) < 0) {
if (errno != ENOENT)
return log_file_set_syscall_error(file, "stat()");
rename_existing = FALSE;
} else if (st.st_ino == file->st_ino &&
CMP_DEV_T(st.st_dev, file->st_dev) &&
/* inode/dev checks are enough when we're rotating the file,
but not when we're replacing a broken log file */
st.st_mtime == file->last_mtime &&
(uoff_t)st.st_size == file->last_size) {
/* no-one else recreated the file */
rename_existing = TRUE;
} else {
/* recreated. use the file if its header is ok */
fd = nfs_safe_open(file->filepath, O_RDWR);
if (fd == -1) {
if (errno != ENOENT) {
log_file_set_syscall_error(file, "open()");
return -1;
}
} else {
file->fd = fd;
if (mail_transaction_log_file_read_hdr(file,
FALSE) > 0 &&
mail_transaction_log_file_stat(file, FALSE) == 0) {
/* yes, it was ok */
(void)file_dotlock_delete(dotlock);
mail_transaction_log_file_add_to_list(file);
return 0;
}
file->fd = -1;
if (close(fd) < 0)
log_file_set_syscall_error(file, "close()");
}
rename_existing = FALSE;
}
if (mail_transaction_log_init_hdr(file->log, &file->hdr) < 0)
return -1;
if (reset) {
/* don't reset modseqs. if we're reseting due to rebuilding
indexes we'll probably want to keep uidvalidity and in such
cases we really don't want to shrink modseqs. */
file->hdr.prev_file_seq = 0;
file->hdr.prev_file_offset = 0;
}
if (write_full(new_fd, &file->hdr, sizeof(file->hdr)) < 0)
return log_file_set_syscall_error(file, "write_full()");
if (file->log->index->fsync_mode == FSYNC_MODE_ALWAYS) {
/* the header isn't important, so don't bother calling
fdatasync() unless it's required */
if (fdatasync(new_fd) < 0)
return log_file_set_syscall_error(file, "fdatasync()");
}
file->fd = new_fd;
ret = mail_transaction_log_file_stat(file, FALSE);
if (file->log->head != NULL && file->log->head->locked) {
/* we'll need to preserve the lock */
if (mail_transaction_log_file_lock(file) < 0)
ret = -1;
}
/* if we return -1 the dotlock deletion code closes the fd */
file->fd = -1;
if (ret < 0)
return -1;
/* keep two log files */
if (rename_existing) {
/* rename() would be nice and easy way to do this, except then
there's a race condition between the rename and
file_dotlock_replace(). during that time the log file
doesn't exist, which could cause problems. */
path2 = t_strconcat(file->filepath, ".2", NULL);
if (unlink(path2) < 0 && errno != ENOENT) {
mail_index_set_error(index, "unlink(%s) failed: %m",
path2);
/* try to link() anyway */
}
if (nfs_safe_link(file->filepath, path2, FALSE) < 0 &&
errno != ENOENT && errno != EEXIST) {
mail_index_set_error(index, "link(%s, %s) failed: %m",
file->filepath, path2);
/* ignore the error. we don't care that much about the
second log file and we're going to overwrite this
first one. */
}
}
if (file_dotlock_replace(dotlock,
DOTLOCK_REPLACE_FLAG_DONT_CLOSE_FD) <= 0)
return -1;
/* success */
file->fd = new_fd;
mail_transaction_log_file_add_to_list(file);
return 0;
}
int mail_transaction_log_file_create(struct mail_transaction_log_file *file,
bool reset)
{
struct mail_index *index = file->log->index;
struct dotlock_settings new_dotlock_set;
struct dotlock *dotlock;
mode_t old_mask;
int fd;
i_assert(!MAIL_INDEX_IS_IN_MEMORY(index));
if (file->log->index->readonly) {
mail_index_set_error(index,
"Can't create log file %s: Index is read-only",
file->filepath);
return -1;
}
mail_transaction_log_get_dotlock_set(file->log, &new_dotlock_set);
new_dotlock_set.lock_suffix = LOG_NEW_DOTLOCK_SUFFIX;
/* With dotlocking we might already have path.lock created, so this
filename has to be different. */
old_mask = umask(index->mode ^ 0666);
fd = file_dotlock_open(&new_dotlock_set, file->filepath, 0, &dotlock);
umask(old_mask);
if (fd == -1)
return log_file_set_syscall_error(file, "file_dotlock_open()");
mail_index_fchown(index, fd, file_dotlock_get_lock_path(dotlock));
/* either fd gets used or the dotlock gets deleted and returned fd
is for the existing file */
if (mail_transaction_log_file_create2(file, fd, reset, &dotlock) < 0) {
if (dotlock != NULL)
(void)file_dotlock_delete(&dotlock);
return -1;
}
return 0;
}
int mail_transaction_log_file_open(struct mail_transaction_log_file *file,
bool check_existing)
{
unsigned int i;
bool ignore_estale;
int ret;
for (i = 0;; i++) {
file->fd = nfs_safe_open(file->filepath, O_RDWR);
if (file->fd == -1) {
if (errno == ENOENT)
return 0;
return log_file_set_syscall_error(file, "open()");
}
ignore_estale = i < MAIL_INDEX_ESTALE_RETRY_COUNT;
if (mail_transaction_log_file_stat(file, ignore_estale) < 0)
ret = -1;
else if (check_existing &&
mail_transaction_log_file_is_dupe(file))
return 0;
else {
ret = mail_transaction_log_file_read_hdr(file,
ignore_estale);
}
if (ret > 0) {
/* success */
break;
}
if (ret == 0) {
/* corrupted */
if (file->log->index->readonly) {
/* don't delete */
} else if (unlink(file->filepath) < 0 &&
errno != ENOENT) {
mail_index_set_error(file->log->index,
"unlink(%s) failed: %m",
file->filepath);
}
return 0;
}
if (errno != ESTALE ||
i == MAIL_INDEX_ESTALE_RETRY_COUNT) {
/* syscall error */
return -1;
}
/* ESTALE - try again */
}
mail_transaction_log_file_add_to_list(file);
return 1;
}
static int
log_file_track_mailbox_sync_offset_hdr(struct mail_transaction_log_file *file,
const void *data, unsigned int size)
{
const struct mail_transaction_header_update *u = data;
const struct mail_index_header *ihdr;
const unsigned int offset_pos =
offsetof(struct mail_index_header, log_file_tail_offset);
const unsigned int offset_size = sizeof(ihdr->log_file_tail_offset);
uint32_t tail_offset;
i_assert(offset_size == sizeof(tail_offset));
if (size < sizeof(*u) || size < sizeof(*u) + u->size) {
mail_transaction_log_file_set_corrupted(file,
"header update extends beyond record size");
return -1;
}
if (u->offset <= offset_pos &&
u->offset + u->size >= offset_pos + offset_size) {
memcpy(&tail_offset,
CONST_PTR_OFFSET(u + 1, offset_pos - u->offset),
sizeof(tail_offset));
if (tail_offset < file->saved_tail_offset) {
if (file->sync_offset < file->saved_tail_sync_offset) {
/* saved_tail_offset was already set in header,
but we still had to resync the file to find
modseqs. ignore this record. */
return 1;
}
mail_index_set_error(file->log->index,
"Transaction log file %s seq %u: "
"log_file_tail_offset update shrank it "
"(%u vs %"PRIuUOFF_T" "
"sync_offset=%"PRIuUOFF_T")",
file->filepath, file->hdr.file_seq,
tail_offset, file->saved_tail_offset,
file->sync_offset);
} else {
file->saved_tail_offset = tail_offset;
if (tail_offset > file->max_tail_offset)
file->max_tail_offset = tail_offset;
return 1;
}
}
return 0;
}
void mail_transaction_update_modseq(const struct mail_transaction_header *hdr,
const void *data, uint64_t *cur_modseq)
{
uint32_t trans_size;
trans_size = mail_index_offset_to_uint32(hdr->size);
i_assert(trans_size != 0);
if (*cur_modseq != 0) {
/* tracking modseqs */
} else if ((hdr->type & MAIL_TRANSACTION_TYPE_MASK) ==
MAIL_TRANSACTION_EXT_INTRO) {
/* modseqs not tracked yet. see if this is a modseq
extension introduction. */
const struct mail_transaction_ext_intro *intro = data;
const unsigned int modseq_ext_len =
strlen(MAIL_INDEX_MODSEQ_EXT_NAME);
if (intro->name_size == modseq_ext_len &&
memcmp(intro + 1, MAIL_INDEX_MODSEQ_EXT_NAME,
modseq_ext_len) == 0) {
/* modseq tracking started */
*cur_modseq += 1;
return;
}
} else {
/* not tracking modseqs */
return;
}
switch (hdr->type & MAIL_TRANSACTION_TYPE_MASK) {
case MAIL_TRANSACTION_EXPUNGE | MAIL_TRANSACTION_EXPUNGE_PROT:
case MAIL_TRANSACTION_EXPUNGE_GUID | MAIL_TRANSACTION_EXPUNGE_PROT:
if ((hdr->type & MAIL_TRANSACTION_EXTERNAL) == 0) {
/* ignore expunge requests */
break;
}
case MAIL_TRANSACTION_APPEND:
case MAIL_TRANSACTION_FLAG_UPDATE:
case MAIL_TRANSACTION_KEYWORD_UPDATE:
case MAIL_TRANSACTION_KEYWORD_RESET:
/* these changes increase modseq */
*cur_modseq += 1;
break;
case MAIL_TRANSACTION_MODSEQ_UPDATE: {
const struct mail_transaction_modseq_update *rec, *end;
end = CONST_PTR_OFFSET(data, trans_size - sizeof(*hdr));
for (rec = data; rec < end; rec++) {
uint64_t modseq = ((uint64_t)rec->modseq_high32 >> 32) |
rec->modseq_low32;
if (*cur_modseq < modseq)
*cur_modseq = modseq;
}
}
}
}
static struct modseq_cache *
modseq_cache_hit(struct mail_transaction_log_file *file, unsigned int idx)
{
struct modseq_cache cache;
if (idx > 0) {
/* @UNSAFE: move it to top */
cache = file->modseq_cache[idx];
memmove(file->modseq_cache + 1, file->modseq_cache,
sizeof(*file->modseq_cache) * idx);
file->modseq_cache[0] = cache;
}
return &file->modseq_cache[0];
}
static struct modseq_cache *
modseq_cache_get_offset(struct mail_transaction_log_file *file, uoff_t offset)
{
unsigned int i, best = -1U;
for (i = 0; i < N_ELEMENTS(file->modseq_cache); i++) {
if (offset < file->modseq_cache[i].offset)
continue;
if (file->modseq_cache[i].offset == 0)
return NULL;
if (offset == file->modseq_cache[i].offset) {
/* exact cache hit */
return modseq_cache_hit(file, i);
}
if (best == -1U ||
file->modseq_cache[i].offset <
file->modseq_cache[best].offset)
best = i;
}
if (best == -1U)
return NULL;
return &file->modseq_cache[best];
}
static struct modseq_cache *
modseq_cache_get_modseq(struct mail_transaction_log_file *file, uint64_t modseq)
{
unsigned int i, best = -1U;
for (i = 0; i < N_ELEMENTS(file->modseq_cache); i++) {
if (modseq < file->modseq_cache[i].highest_modseq)
continue;
if (file->modseq_cache[i].offset == 0)
return NULL;
if (modseq == file->modseq_cache[i].highest_modseq) {
/* exact cache hit */
return modseq_cache_hit(file, i);
}
if (best == -1U ||
file->modseq_cache[i].highest_modseq <
file->modseq_cache[best].highest_modseq)
best = i;
}
if (best == -1U)
return NULL;
return &file->modseq_cache[best];
}
static int
log_get_synced_record(struct mail_transaction_log_file *file, uoff_t *offset,
const struct mail_transaction_header **hdr_r)
{
const struct mail_transaction_header *hdr;
uint32_t trans_size;
hdr = CONST_PTR_OFFSET(file->buffer->data,
*offset - file->buffer_offset);
/* we've already synced this record at some point. it should
be valid. */
trans_size = mail_index_offset_to_uint32(hdr->size);
if (trans_size < sizeof(*hdr) ||
*offset - file->buffer_offset + trans_size > file->buffer->used) {
mail_transaction_log_file_set_corrupted(file,
"Transaction log corrupted unexpectedly at "
"%"PRIuUOFF_T": Invalid size %u (type=%x)",
*offset, trans_size, hdr->type);
return -1;
}
*offset += trans_size;
*hdr_r = hdr;
return 0;
}
int mail_transaction_log_file_get_highest_modseq_at(
struct mail_transaction_log_file *file,
uoff_t offset, uint64_t *highest_modseq_r)
{
const struct mail_transaction_header *hdr;
struct modseq_cache *cache;
uoff_t cur_offset;
uint64_t cur_modseq;
int ret;
i_assert(offset <= file->sync_offset);
if (offset == file->sync_offset) {
*highest_modseq_r = file->sync_highest_modseq;
return 0;
}
cache = modseq_cache_get_offset(file, offset);
if (cache == NULL) {
/* nothing usable in cache - scan from beginning */
cur_offset = file->hdr.hdr_size;
cur_modseq = file->hdr.initial_modseq;
} else if (cache->offset == offset) {
/* exact cache hit */
*highest_modseq_r = cache->highest_modseq;
return 0;
} else {
/* use cache to skip over some records */
cur_offset = cache->offset;
cur_modseq = cache->highest_modseq;
}
ret = mail_transaction_log_file_map(file, cur_offset, offset);
if (ret <= 0) {
if (ret < 0)
return -1;
mail_index_set_error(file->log->index,
"%s: Transaction log corrupted, can't get modseq",
file->filepath);
return -1;
}
i_assert(cur_offset >= file->buffer_offset);
i_assert(cur_offset + file->buffer->used >= offset);
while (cur_offset < offset) {
if (log_get_synced_record(file, &cur_offset, &hdr) < 0)
return- 1;
mail_transaction_update_modseq(hdr, hdr + 1, &cur_modseq);
}
/* @UNSAFE: cache the value */
memmove(file->modseq_cache + 1, file->modseq_cache,
sizeof(*file->modseq_cache) *
(N_ELEMENTS(file->modseq_cache) - 1));
file->modseq_cache[0].offset = cur_offset;
file->modseq_cache[0].highest_modseq = cur_modseq;
*highest_modseq_r = cur_modseq;
return 0;
}
int mail_transaction_log_file_get_modseq_next_offset(
struct mail_transaction_log_file *file,
uint64_t modseq, uoff_t *next_offset_r)
{
const struct mail_transaction_header *hdr;
struct modseq_cache *cache;
uoff_t cur_offset;
uint64_t cur_modseq;
int ret;
if (modseq >= file->sync_highest_modseq) {
*next_offset_r = file->sync_offset;
return 0;
}
if (modseq == file->hdr.initial_modseq) {
*next_offset_r = file->hdr.hdr_size;
return 0;
}
cache = modseq_cache_get_modseq(file, modseq);
if (cache == NULL) {
/* nothing usable in cache - scan from beginning */
cur_offset = file->hdr.hdr_size;
cur_modseq = file->hdr.initial_modseq;
} else if (cache->highest_modseq == modseq) {
/* exact cache hit */
*next_offset_r = cache->offset;
return 0;
} else {
/* use cache to skip over some records */
cur_offset = cache->offset;
cur_modseq = cache->highest_modseq;
}
ret = mail_transaction_log_file_map(file, cur_offset,
file->sync_offset);
if (ret <= 0) {
if (ret < 0)
return -1;
mail_index_set_error(file->log->index,
"%s: Transaction log corrupted, can't get modseq",
file->filepath);
return -1;
}
i_assert(cur_offset >= file->buffer_offset);
while (cur_offset < file->sync_offset) {
if (log_get_synced_record(file, &cur_offset, &hdr) < 0)
return -1;
mail_transaction_update_modseq(hdr, hdr + 1, &cur_modseq);
if (cur_modseq >= modseq)
break;
}
if (cur_offset == file->sync_offset) {
/* if we got to sync_offset, cur_modseq should be
sync_highest_modseq */
mail_index_set_error(file->log->index,
"%s: Transaction log changed unexpectedly, "
"can't get modseq", file->filepath);
return -1;
}
/* @UNSAFE: cache the value */
memmove(file->modseq_cache + 1, file->modseq_cache,
sizeof(*file->modseq_cache) *
(N_ELEMENTS(file->modseq_cache) - 1));
file->modseq_cache[0].offset = cur_offset;
file->modseq_cache[0].highest_modseq = cur_modseq;
*next_offset_r = cur_offset;
return 0;
}
static int
log_file_track_sync(struct mail_transaction_log_file *file,
const struct mail_transaction_header *hdr,
unsigned int trans_size)
{
const void *data = hdr + 1;
int ret;
mail_transaction_update_modseq(hdr, hdr + 1,
&file->sync_highest_modseq);
if ((hdr->type & MAIL_TRANSACTION_EXTERNAL) == 0)
return 0;
/* external transactions: */
switch (hdr->type & MAIL_TRANSACTION_TYPE_MASK) {
case MAIL_TRANSACTION_HEADER_UPDATE:
/* see if this updates mailbox_sync_offset */
ret = log_file_track_mailbox_sync_offset_hdr(file, data,
trans_size -
sizeof(*hdr));
if (ret != 0)
return ret < 0 ? -1 : 0;
break;
case MAIL_TRANSACTION_INDEX_DELETED:
if (file->sync_offset < file->index_undeleted_offset)
break;
file->log->index->index_deleted = TRUE;
file->index_deleted_offset = file->sync_offset + trans_size;
break;
case MAIL_TRANSACTION_INDEX_UNDELETED:
if (file->sync_offset < file->index_deleted_offset)
break;
file->log->index->index_deleted = FALSE;
file->log->index->index_delete_requested = FALSE;
file->index_undeleted_offset = file->sync_offset + trans_size;
break;
}
if (file->max_tail_offset == file->sync_offset) {
/* external transactions aren't synced to mailbox. we can
update mailbox sync offset to skip this transaction to
avoid re-reading it at the next sync. */
file->max_tail_offset += trans_size;
}
return 0;
}
static int
mail_transaction_log_file_sync(struct mail_transaction_log_file *file)
{
const struct mail_transaction_header *hdr;
const void *data;
struct stat st;
size_t size, avail;
uint32_t trans_size = 0;
i_assert(file->sync_offset >= file->buffer_offset);
data = buffer_get_data(file->buffer, &size);
if (file->buffer_offset + size < file->sync_offset) {
mail_transaction_log_file_set_corrupted(file,
"log file shrank (%"PRIuUOFF_T" < %"PRIuUOFF_T")",
file->buffer_offset + (uoff_t)size, file->sync_offset);
return -1;
}
while (file->sync_offset - file->buffer_offset + sizeof(*hdr) <= size) {
hdr = CONST_PTR_OFFSET(data, file->sync_offset -
file->buffer_offset);
trans_size = mail_index_offset_to_uint32(hdr->size);
if (trans_size == 0) {
/* unfinished */
return 1;
}
if (trans_size < sizeof(*hdr)) {
mail_transaction_log_file_set_corrupted(file,
"hdr.size too small (%u)", trans_size);
return -1;
}
if (file->sync_offset - file->buffer_offset + trans_size > size)
break;
/* transaction has been fully written */
if (log_file_track_sync(file, hdr, trans_size) < 0)
return -1;
file->sync_offset += trans_size;
trans_size = 0;
}
if (file->mmap_base != NULL && !file->locked) {
/* Now that all the mmaped pages have page faulted, check if
the file had changed while doing that. Only after the last
page has faulted, the size returned by fstat() can be
trusted. Otherwise it might point to a page boundary while
the next page is still being written.
Without this check we might see partial transactions,
sometimes causing "Extension record updated without intro
prefix" errors. */
if (fstat(file->fd, &st) < 0)
return log_file_set_syscall_error(file, "fstat()");
if ((uoff_t)st.st_size != file->last_size) {
file->last_size = st.st_size;
return 0;
}
}
avail = file->sync_offset - file->buffer_offset;
if (avail != size) {
/* There's more data than we could sync at the moment. If the
last record's size wasn't valid, we can't know if it will
be updated unless we've locked the log. */
if (trans_size != 0) {
/* pread()s or the above fstat() check for mmaps should
have guaranteed that this doesn't happen */
mail_transaction_log_file_set_corrupted(file,
"hdr.size too large (%u)", trans_size);
return -1;
} else if (file->locked) {
mail_transaction_log_file_set_corrupted(file,
"Unexpected garbage at EOF");
return -1;
}
/* The size field will be updated soon */
mail_index_flush_read_cache(file->log->index, file->filepath,
file->fd, file->locked);
}
if (file->next != NULL &&
file->hdr.file_seq == file->next->hdr.prev_file_seq &&
file->next->hdr.prev_file_offset != file->sync_offset) {
mail_transaction_log_file_set_corrupted(file,
"Invalid transaction log size "
"(%"PRIuUOFF_T" vs %u): %s", file->sync_offset,
file->log->head->hdr.prev_file_offset, file->filepath);
return -1;
}
return 1;
}
static int
mail_transaction_log_file_insert_read(struct mail_transaction_log_file *file,
uoff_t offset)
{
void *data;
size_t size;
ssize_t ret;
size = file->buffer_offset - offset;
buffer_copy(file->buffer, size, file->buffer, 0, (size_t)-1);
data = buffer_get_space_unsafe(file->buffer, 0, size);
ret = pread_full(file->fd, data, size, offset);
if (ret > 0) {
/* success */
file->buffer_offset -= size;
return 1;
}
/* failure. don't leave ourself to inconsistent state */
buffer_copy(file->buffer, 0, file->buffer, size, (size_t)-1);
buffer_set_used_size(file->buffer, file->buffer->used - size);
if (ret == 0) {
mail_transaction_log_file_set_corrupted(file, "file shrank");
return 0;
} else if (errno == ESTALE) {
/* log file was deleted in NFS server, fail silently */
return 0;
} else {
return log_file_set_syscall_error(file, "pread()");
}
}
static int
mail_transaction_log_file_read_more(struct mail_transaction_log_file *file)
{
void *data;
size_t size;
uint32_t read_offset;
ssize_t ret;
read_offset = file->buffer_offset + buffer_get_used_size(file->buffer);
do {
data = buffer_append_space_unsafe(file->buffer, LOG_PREFETCH);
ret = pread(file->fd, data, LOG_PREFETCH, read_offset);
if (ret > 0)
read_offset += ret;
size = read_offset - file->buffer_offset;
buffer_set_used_size(file->buffer, size);
} while (ret > 0 || (ret < 0 && errno == EINTR));
file->last_size = read_offset;
if (ret < 0) {
if (errno == ESTALE) {
/* log file was deleted in NFS server, fail silently */
return 0;
}
return log_file_set_syscall_error(file, "pread()");
}
return 1;
}
static bool
mail_transaction_log_file_need_nfs_flush(struct mail_transaction_log_file *file)
{
const struct mail_index_header *hdr = &file->log->index->map->hdr;
uoff_t max_offset = file->last_size;
if (file->next != NULL &&
file->hdr.file_seq == file->next->hdr.prev_file_seq &&
file->next->hdr.prev_file_offset != max_offset) {
/* we already have a newer log file which says that we haven't
synced the entire file. */
return TRUE;
}
if (file->hdr.file_seq == hdr->log_file_seq &&
max_offset < hdr->log_file_head_offset)
return TRUE;
return FALSE;
}
static int
mail_transaction_log_file_read(struct mail_transaction_log_file *file,
uoff_t start_offset, bool nfs_flush)
{
int ret;
i_assert(file->mmap_base == NULL);
/* NFS: if file isn't locked, we're optimistic that we can read enough
data without flushing attribute cache. if after reading we notice
that we really should have read more, flush the cache and try again.
if file is locked, the attribute cache was already flushed when
refreshing the log. */
if (file->log->nfs_flush && nfs_flush) {
if (!file->locked)
nfs_flush_attr_cache_unlocked(file->filepath);
else {
nfs_flush_attr_cache_fd_locked(file->filepath,
file->fd);
}
}
if (file->buffer != NULL && file->buffer_offset > start_offset) {
/* we have to insert missing data to beginning of buffer */
ret = mail_transaction_log_file_insert_read(file, start_offset);
if (ret <= 0)
return ret;
}
if (file->buffer == NULL) {
file->buffer =
buffer_create_dynamic(default_pool, LOG_PREFETCH);
file->buffer_offset = start_offset;
}
if ((ret = mail_transaction_log_file_read_more(file)) <= 0)
return ret;
if (file->log->nfs_flush && !nfs_flush &&
mail_transaction_log_file_need_nfs_flush(file)) {
/* we didn't read enough data. flush and try again. */
return mail_transaction_log_file_read(file, start_offset, TRUE);
}
if ((ret = mail_transaction_log_file_sync(file)) <= 0) {
i_assert(ret != 0); /* happens only with mmap */
return -1;
}
i_assert(file->sync_offset >= file->buffer_offset);
buffer_set_used_size(file->buffer,
file->sync_offset - file->buffer_offset);
return 1;
}
static int
log_file_map_check_offsets(struct mail_transaction_log_file *file,
uoff_t start_offset, uoff_t end_offset)
{
if (start_offset > file->sync_offset) {
/* broken start offset */
mail_index_set_error(file->log->index,
"%s: start_offset (%"PRIuUOFF_T") > "
"current sync_offset (%"PRIuUOFF_T")",
file->filepath, start_offset, file->sync_offset);
return 0;
}
if (end_offset != (uoff_t)-1 && end_offset > file->sync_offset) {
mail_index_set_error(file->log->index,
"%s: end_offset (%"PRIuUOFF_T") > "
"current sync_offset (%"PRIuUOFF_T")",
file->filepath, start_offset, file->sync_offset);
return 0;
}
return 1;
}
static int
mail_transaction_log_file_mmap(struct mail_transaction_log_file *file)
{
if (file->buffer != NULL) {
/* in case we just switched to mmaping */
buffer_free(&file->buffer);
}
file->mmap_size = file->last_size;
file->mmap_base = mmap(NULL, file->mmap_size, PROT_READ, MAP_SHARED,
file->fd, 0);
if (file->mmap_base == MAP_FAILED) {
file->mmap_base = NULL;
file->mmap_size = 0;
return log_file_set_syscall_error(file, "mmap()");
}
if (file->mmap_size > mmap_get_page_size()) {
if (madvise(file->mmap_base, file->mmap_size,
MADV_SEQUENTIAL) < 0)
log_file_set_syscall_error(file, "madvise()");
}
buffer_create_const_data(&file->mmap_buffer,
file->mmap_base, file->mmap_size);
file->buffer = &file->mmap_buffer;
file->buffer_offset = 0;
return 0;
}
static void
mail_transaction_log_file_munmap(struct mail_transaction_log_file *file)
{
if (file->mmap_base == NULL)
return;
if (munmap(file->mmap_base, file->mmap_size) < 0)
log_file_set_syscall_error(file, "munmap()");
file->mmap_base = NULL;
file->mmap_size = 0;
buffer_free(&file->buffer);
}
static int
mail_transaction_log_file_map_mmap(struct mail_transaction_log_file *file,
uoff_t start_offset)
{
struct stat st;
int ret;
/* we are going to mmap() this file, but it's not necessarily
mmaped currently. */
i_assert(file->buffer_offset == 0 || file->mmap_base == NULL);
i_assert(file->mmap_size == 0 || file->mmap_base != NULL);
if (fstat(file->fd, &st) < 0)
return log_file_set_syscall_error(file, "fstat()");
file->last_size = st.st_size;
if ((uoff_t)st.st_size < file->sync_offset) {
mail_transaction_log_file_set_corrupted(file,
"file size shrank");
return 0;
}
if (file->buffer != NULL && file->buffer_offset <= start_offset &&
(uoff_t)st.st_size == file->buffer_offset + file->buffer->used) {
/* we already have the whole file mapped */
if ((ret = mail_transaction_log_file_sync(file)) < 0)
return 0;
if (ret > 0)
return 1;
/* size changed, re-mmap */
}
do {
mail_transaction_log_file_munmap(file);
if (file->last_size - start_offset < mmap_get_page_size()) {
/* just reading the file is probably faster */
return mail_transaction_log_file_read(file,
start_offset,
FALSE);
}
if (mail_transaction_log_file_mmap(file) < 0)
return -1;
if ((ret = mail_transaction_log_file_sync(file)) < 0)
return 0;
} while (ret == 0);
return 1;
}
int mail_transaction_log_file_map(struct mail_transaction_log_file *file,
uoff_t start_offset, uoff_t end_offset)
{
struct mail_index *index = file->log->index;
size_t size;
int ret;
if (file->hdr.indexid == 0) {
/* corrupted */
return 0;
}
i_assert(start_offset >= file->hdr.hdr_size);
i_assert(start_offset <= end_offset);
if (index->log_locked && file == file->log->head &&
end_offset == (uoff_t)-1) {
/* we're not interested of going further than sync_offset */
if (log_file_map_check_offsets(file, start_offset,
end_offset) == 0)
return 0;
i_assert(start_offset <= file->sync_offset);
end_offset = file->sync_offset;
}
if (file->buffer != NULL && file->buffer_offset <= start_offset) {
/* see if we already have it */
size = buffer_get_used_size(file->buffer);
if (file->buffer_offset + size >= end_offset)
return 1;
}
if (MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file)) {
if (start_offset < file->buffer_offset) {
/* we had moved the log to memory but failed to read
the beginning of the log file */
mail_index_set_error(index,
"%s: Beginning of the log isn't available",
file->filepath);
return 0;
}
return log_file_map_check_offsets(file, start_offset,
end_offset);
}
if (start_offset > file->sync_offset)
mail_transaction_log_file_skip_to_head(file);
if (start_offset > file->sync_offset) {
/* although we could just skip over the unwanted data, we have
to sync everything so that modseqs are calculated
correctly */
start_offset = file->sync_offset;
}
if ((file->log->index->flags & MAIL_INDEX_OPEN_FLAG_MMAP_DISABLE) == 0)
ret = mail_transaction_log_file_map_mmap(file, start_offset);
else {
mail_transaction_log_file_munmap(file);
ret = mail_transaction_log_file_read(file, start_offset, FALSE);
}
return ret <= 0 ? ret :
log_file_map_check_offsets(file, start_offset, end_offset);
}
void mail_transaction_log_file_move_to_memory(struct mail_transaction_log_file
*file)
{
buffer_t *buf;
if (MAIL_TRANSACTION_LOG_FILE_IN_MEMORY(file))
return;
if (file->mmap_base != NULL) {
/* just copy to memory */
i_assert(file->buffer_offset == 0);
buf = buffer_create_dynamic(default_pool, file->mmap_size);
buffer_append(buf, file->mmap_base, file->mmap_size);
buffer_free(&file->buffer);
file->buffer = buf;
/* and lose the mmap */
if (munmap(file->mmap_base, file->mmap_size) < 0)
log_file_set_syscall_error(file, "munmap()");
file->mmap_base = NULL;
} else if (file->buffer_offset != 0) {
/* we don't have the full log in the memory. read it. */
(void)mail_transaction_log_file_read(file, 0, FALSE);
}
file->last_size = 0;
if (close(file->fd) < 0)
log_file_set_syscall_error(file, "close()");
file->fd = -1;
i_free(file->filepath);
file->filepath = i_strdup(file->log->filepath);
}