From: Timo Sirainen <tss@iki.fi>
Date: Thu, 29 Apr 2004 00:08:00 +0000 (+0300)
Subject: Don't modify index file when creating new transaction log.
X-Git-Tag: 1.1.alpha1~4171
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=40ef82c46f6652412b068ebcdac7c3e74840a284;p=thirdparty%2Fdovecot%2Fcore.git

Don't modify index file when creating new transaction log.

--HG--
branch : HEAD
---

diff --git a/src/lib-index/mail-index-private.h b/src/lib-index/mail-index-private.h
index 342ee7e5c6..c33275f916 100644
--- a/src/lib-index/mail-index-private.h
+++ b/src/lib-index/mail-index-private.h
@@ -70,7 +70,7 @@ struct mail_index {
 	uint32_t indexid;
 
 	int lock_type, shared_lock_count, excl_lock_count;
-	unsigned int lock_id, opening_lock_id;
+	unsigned int lock_id;
 	char *copy_lock_path;
 	struct dotlock dotlock;
 
diff --git a/src/lib-index/mail-index.c b/src/lib-index/mail-index.c
index 71f74d375b..97b18a04d2 100644
--- a/src/lib-index/mail-index.c
+++ b/src/lib-index/mail-index.c
@@ -538,10 +538,10 @@ static int
 mail_index_open2(struct mail_index *index, enum mail_index_open_flags flags)
 {
 	struct mail_index_header hdr;
+	unsigned int lock_id = 0;
 	int ret;
 
-	index->opening_lock_id = 0;
-	ret = mail_index_try_open(index, &index->opening_lock_id);
+	ret = mail_index_try_open(index, &lock_id);
 	if (ret > 0)
 		hdr = *index->hdr;
 	else if (ret == 0) {
@@ -559,10 +559,8 @@ mail_index_open2(struct mail_index *index, enum mail_index_open_flags flags)
 	if (index->log == NULL)
 		return -1;
 
-	if (index->opening_lock_id != 0) {
-		mail_index_unlock(index, index->opening_lock_id);
-                index->opening_lock_id = 0;
-	}
+	if (lock_id != 0)
+		mail_index_unlock(index, lock_id);
 	return index->fd != -1 ? 1 : mail_index_create(index, &hdr);
 }
 
diff --git a/src/lib-index/mail-transaction-log-view.c b/src/lib-index/mail-transaction-log-view.c
index d443a2b146..56e9c9d275 100644
--- a/src/lib-index/mail-transaction-log-view.c
+++ b/src/lib-index/mail-transaction-log-view.c
@@ -88,8 +88,33 @@ mail_transaction_log_view_set(struct mail_transaction_log_view *view,
         mail_transaction_log_view_close_files(view);
 
 	ret = mail_transaction_log_file_find(view->log, min_file_seq, &file);
-	if (ret <= 0)
-		return -1;
+	if (ret <= 0) {
+		if (ret == 0 &&
+		    min_file_seq == view->log->tail->hdr.file_seq-1 &&
+		    min_file_offset == view->log->tail->hdr.prev_file_offset) {
+			/* we can skip this */
+			min_file_seq++;
+			min_file_offset =
+				sizeof(struct mail_transaction_log_header);
+			ret = mail_transaction_log_file_find(view->log,
+							     min_file_seq,
+							     &file);
+		}
+
+		if (ret == 0) {
+			mail_index_set_error(view->log->index,
+				"Lost transaction log file %s seq %u",
+				view->log->tail->filepath, min_file_seq);
+		}
+		if (ret <= 0)
+			return -1;
+
+		if (min_file_seq > max_file_seq) {
+			/* empty view */
+			max_file_seq = min_file_seq;
+			max_file_offset = min_file_offset;
+		}
+	}
 	end_offset = min_file_seq == max_file_seq ?
 		max_file_offset : (uoff_t)-1;
 	ret = mail_transaction_log_file_map(file, min_file_offset, end_offset);
diff --git a/src/lib-index/mail-transaction-log.c b/src/lib-index/mail-transaction-log.c
index 65850512d4..ea3293a5dc 100644
--- a/src/lib-index/mail-transaction-log.c
+++ b/src/lib-index/mail-transaction-log.c
@@ -61,6 +61,12 @@ mail_transaction_log_file_set_corrupted(struct mail_transaction_log_file *file,
 	va_end(va);
 }
 
+#define INDEX_HAS_MISSING_LOGS(index, file) \
+	((file)->hdr.file_seq != (index)->hdr->log_file_seq && \
+	 ((file)->hdr.file_seq != (index)->hdr->log_file_seq+1 || \
+	  (file)->hdr.prev_file_offset != (index)->hdr->log_file_offset))
+
+
 static int mail_transaction_log_check_file_seq(struct mail_transaction_log *log)
 {
 	struct mail_index *index = log->index;
@@ -77,7 +83,7 @@ static int mail_transaction_log_check_file_seq(struct mail_transaction_log *log)
 		ret = mail_index_map(index, FALSE);
 		if (ret <= 0)
 			ret = -1;
-		else if (file->hdr.file_seq != index->hdr->log_file_seq) {
+		else if (INDEX_HAS_MISSING_LOGS(index, file)) {
 			/* broken - fix it by creating a new log file */
 			ret = mail_transaction_log_rotate(log);
 		}
@@ -104,11 +110,10 @@ mail_transaction_log_open_or_create(struct mail_index *index)
 	}
 
 	if (index->fd != -1 &&
-	    log->head->hdr.file_seq != index->hdr->log_file_seq) {
+	    INDEX_HAS_MISSING_LOGS(index, log->head)) {
 		/* head log file isn't same as head index file -
 		   shouldn't happen except in race conditions. lock them and
-		   check again - FIXME: missing error handling.
-		   FIXME: index->hdr check crashes if we created the log */
+		   check again - FIXME: missing error handling. */
 		(void)mail_transaction_log_check_file_seq(log);
 	}
 	return log;
@@ -280,14 +285,13 @@ mail_transaction_log_file_read_hdr(struct mail_transaction_log_file *file,
 	return 1;
 }
 
-static int mail_transaction_log_file_create(struct mail_transaction_log *log,
-					    const char *path,
-					    dev_t dev, ino_t ino)
+static int
+mail_transaction_log_file_create(struct mail_transaction_log *log,
+				 const char *path, dev_t dev, ino_t ino)
 {
 	struct mail_index *index = log->index;
 	struct mail_transaction_log_header hdr;
 	struct stat st;
-	unsigned int lock_id;
 	int fd, fd2, ret;
 
 	fd = file_dotlock_open(path, NULL, LOG_DOTLOCK_TIMEOUT,
@@ -326,37 +330,9 @@ static int mail_transaction_log_file_create(struct mail_transaction_log *log,
 	hdr.indexid = index->indexid;
 	hdr.used_size = sizeof(hdr);
 
-	if (index->fd != -1) {
-		index->log_locked = TRUE; /* kludging around assert.. */
-		if (mail_index_lock_exclusive(index, &lock_id) < 0) {
-			(void)file_dotlock_delete(path, fd);
-			index->log_locked = FALSE;
-			return -1;
-		}
-
-		ret = mail_index_map(index, FALSE);
-		if (ret > 0) {
-			/* update log_file_* fields in header */
-			struct mail_index_header idx_hdr;
-
-			idx_hdr = *index->hdr;
-			idx_hdr.log_file_seq++;
-			idx_hdr.log_file_offset = sizeof(hdr);
-			if (mail_index_write_header(index, &idx_hdr) < 0)
-				ret = -1;
-		}
-		hdr.file_seq = index->hdr->log_file_seq;
-		mail_index_unlock(index, lock_id);
-		index->log_locked = FALSE;
-
-		if (ret <= 0) {
-			(void)file_dotlock_delete(path, fd);
-			return -1;
-		}
-	} else {
-		/* creating new index file */
-		hdr.file_seq = index->hdr->log_file_seq+1;
-	}
+	if (index->fd != -1)
+		hdr.prev_file_offset = index->hdr->log_file_offset;
+	hdr.file_seq = index->hdr->log_file_seq+1;
 
 	if (write_full(fd, &hdr, sizeof(hdr)) < 0) {
 		mail_index_file_set_syscall_error(index, path, "write_full()");
diff --git a/src/lib-index/mail-transaction-log.h b/src/lib-index/mail-transaction-log.h
index 7d271e019d..bc70e600a5 100644
--- a/src/lib-index/mail-transaction-log.h
+++ b/src/lib-index/mail-transaction-log.h
@@ -6,6 +6,7 @@
 struct mail_transaction_log_header {
 	uint32_t indexid;
 	uint32_t file_seq;
+	uint32_t prev_file_offset;
 	uint32_t used_size;
 };