From 0fc7529c01e601c786d77e590aaf674ade8dd99e Mon Sep 17 00:00:00 2001
From: Joe Thornber <ejt@redhat.com>
Date: Mon, 14 Oct 2019 09:21:38 +0100
Subject: [PATCH] [cache_repair, thin_repair] fix bug introduced in recent
 patch

I hadn't realised that check_file_exists() also checked that it was
a regular file, which we don't want for the couple of uses I recently
added.

This patch adds an optional arg must_be_regular_file, and defaults
it to true, preserving the original behaviour.  The recent additions
have this set to false.
---
 base/file_utils.cc               | 4 ++--
 base/file_utils.h                | 2 +-
 caching/cache_repair.cc          | 2 +-
 thin-provisioning/thin_repair.cc | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/base/file_utils.cc b/base/file_utils.cc
index ba8957c..7883cfe 100644
--- a/base/file_utils.cc
+++ b/base/file_utils.cc
@@ -66,13 +66,13 @@ file_utils::file_exists(string const &path) {
 }
 
 void
-file_utils::check_file_exists(string const &file) {
+file_utils::check_file_exists(string const &file, bool must_be_regular_file) {
 	struct stat info;
 	int r = ::stat(file.c_str(), &info);
 	if (r)
 		throw runtime_error("Couldn't stat file");
 
-	if (!S_ISREG(info.st_mode))
+	if (must_be_regular_file && !S_ISREG(info.st_mode))
 		throw runtime_error("Not a regular file");
 }
 
diff --git a/base/file_utils.h b/base/file_utils.h
index 2ee20ab..3edcc9e 100644
--- a/base/file_utils.h
+++ b/base/file_utils.h
@@ -10,7 +10,7 @@
 namespace file_utils {
 	int open_file(std::string const &path, int flags);
 	bool file_exists(std::string const &path);
-	void check_file_exists(std::string const &file);
+	void check_file_exists(std::string const &file, bool must_be_regular_file = true);
 	int create_block_file(std::string const &path, off_t file_size);
 	int open_block_file(std::string const &path, off_t min_size, bool writeable, bool excl = true);
 	uint64_t get_file_length(std::string const &file);
diff --git a/caching/cache_repair.cc b/caching/cache_repair.cc
index bc365c9..8a837a8 100644
--- a/caching/cache_repair.cc
+++ b/caching/cache_repair.cc
@@ -32,7 +32,7 @@ namespace {
 	int repair(string const &old_path, string const &new_path) {
 		bool metadata_touched = false;
 		try {
-			file_utils::check_file_exists(new_path);
+			file_utils::check_file_exists(new_path, false);
 			metadata_touched = true;
 			metadata_dump(open_metadata_for_read(old_path),
 				      output_emitter(new_path),
diff --git a/thin-provisioning/thin_repair.cc b/thin-provisioning/thin_repair.cc
index 6f464e2..0673753 100644
--- a/thin-provisioning/thin_repair.cc
+++ b/thin-provisioning/thin_repair.cc
@@ -22,7 +22,7 @@ namespace {
 		try {
 			// block size gets updated by the restorer
 			block_manager<>::ptr new_bm = open_bm(new_path, block_manager<>::READ_WRITE);
-			file_utils::check_file_exists(old_path);
+			file_utils::check_file_exists(old_path, false);
 			metadata_touched = true;
 			metadata::ptr new_md(new metadata(new_bm, metadata::CREATE, 128, 0));
 			emitter::ptr e = create_restore_emitter(new_md);