From 2f705f3d22a6251791c2bc4e5bd72e76f6c336be Mon Sep 17 00:00:00 2001
From: Timo Sirainen <tss@iki.fi>
Date: Fri, 22 Feb 2013 10:01:06 +0200
Subject: [PATCH] mdbox: If m.X file has no mails, don't try to fix it
 infinitely in storage rebuild.

---
 src/lib-storage/index/dbox-common/dbox-file-fix.c  | 14 ++++++++++++--
 src/lib-storage/index/dbox-common/dbox-file.h      |  3 ++-
 .../index/dbox-multi/mdbox-storage-rebuild.c       |  6 ++++--
 .../index/dbox-single/sdbox-sync-rebuild.c         |  2 +-
 4 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/src/lib-storage/index/dbox-common/dbox-file-fix.c b/src/lib-storage/index/dbox-common/dbox-file-fix.c
index 4a04150063..84c4a9e2c4 100644
--- a/src/lib-storage/index/dbox-common/dbox-file-fix.c
+++ b/src/lib-storage/index/dbox-common/dbox-file-fix.c
@@ -291,7 +291,7 @@ int dbox_file_fix(struct dbox_file *file, uoff_t start_offset)
 {
 	struct ostream *output;
 	const char *dir, *p, *temp_path, *broken_path;
-	bool deleted;
+	bool deleted, have_messages;
 	int fd, ret;
 
 	i_assert(dbox_file_is_open(file));
@@ -307,6 +307,7 @@ int dbox_file_fix(struct dbox_file *file, uoff_t start_offset)
 
 	output = o_stream_create_fd_file(fd, 0, FALSE);
 	ret = dbox_file_fix_write_stream(file, start_offset, temp_path, output);
+	have_messages = output->offset > file->file_header_size;
 	o_stream_unref(&output);
 	if (close(fd) < 0) {
 		mail_storage_set_critical(&file->storage->storage,
@@ -332,6 +333,15 @@ int dbox_file_fix(struct dbox_file *file, uoff_t start_offset)
 		i_warning("dbox: Copy of the broken file saved to %s",
 			  broken_path);
 	}
+	if (!have_messages) {
+		/* the resulting file has no messages. just delete the file. */
+		dbox_file_close(file);
+		if (unlink(temp_path) < 0)
+			i_error("unlink(%s) failed: %m", temp_path);
+		if (unlink(file->cur_path) < 0)
+			i_error("unlink(%s) failed: %m", file->cur_path);
+		return 0;
+	}
 	if (rename(temp_path, file->cur_path) < 0) {
 		mail_storage_set_critical(&file->storage->storage,
 					  "rename(%s, %s) failed: %m",
@@ -347,5 +357,5 @@ int dbox_file_fix(struct dbox_file *file, uoff_t start_offset)
 			file->cur_path);
 		return -1;
 	}
-	return 0;
+	return 1;
 }
diff --git a/src/lib-storage/index/dbox-common/dbox-file.h b/src/lib-storage/index/dbox-common/dbox-file.h
index bb7b81d0af..4787a84e0f 100644
--- a/src/lib-storage/index/dbox-common/dbox-file.h
+++ b/src/lib-storage/index/dbox-common/dbox-file.h
@@ -190,7 +190,8 @@ uoff_t dbox_file_get_plaintext_size(struct dbox_file *file);
 
 /* Fix a broken dbox file by rename()ing over it with a fixed file. Everything
    before start_offset is assumed to be valid and is simply copied. The file
-   is reopened afterwards. Returns 0 if ok, -1 if I/O error. */
+   is reopened afterwards. Returns 1 if ok, 0 if the resulting file has no
+   mails and was deleted, -1 if I/O error. */
 int dbox_file_fix(struct dbox_file *file, uoff_t start_offset);
 /* Delete the given dbox file. Returns 1 if deleted, 0 if file wasn't found
    or -1 if error. */
diff --git a/src/lib-storage/index/dbox-multi/mdbox-storage-rebuild.c b/src/lib-storage/index/dbox-multi/mdbox-storage-rebuild.c
index cc665f9e17..b7c733f8a3 100644
--- a/src/lib-storage/index/dbox-multi/mdbox-storage-rebuild.c
+++ b/src/lib-storage/index/dbox-multi/mdbox-storage-rebuild.c
@@ -152,9 +152,11 @@ static int rebuild_file_mails(struct mdbox_storage_rebuild_context *ctx,
 				/* use existing file header if it was ok */
 				prev_offset = offset;
 			}
-			if (dbox_file_fix(file, prev_offset) < 0) {
-				ret = -1;
+			if ((ret = dbox_file_fix(file, prev_offset)) < 0)
 				break;
+			if (ret == 0) {
+				/* file was deleted */
+				return 1;
 			}
 			fixed = TRUE;
 			if (!first) {
diff --git a/src/lib-storage/index/dbox-single/sdbox-sync-rebuild.c b/src/lib-storage/index/dbox-single/sdbox-sync-rebuild.c
index baaef38cf8..d66115197c 100644
--- a/src/lib-storage/index/dbox-single/sdbox-sync-rebuild.c
+++ b/src/lib-storage/index/dbox-single/sdbox-sync-rebuild.c
@@ -39,7 +39,7 @@ sdbox_sync_add_file_index(struct dbox_sync_rebuild_context *ctx,
 		ret = dbox_file_seek(file, 0);
 	}
 	if (ret == 0) {
-		if ((ret = dbox_file_fix(file, 0)) == 0)
+		if ((ret = dbox_file_fix(file, 0)) > 0)
 			ret = dbox_file_seek(file, 0);
 	}
 
-- 
2.47.3