From 87271666ac4102b548c4d45f6fbfa66e95f2f23f Mon Sep 17 00:00:00 2001
From: Marcus Holland-Moritz <github@mhxnet.de>
Date: Sat, 5 Nov 2022 18:45:48 +0100
Subject: [PATCH] Autogenerate compression type code

---
 include/dwarfs/block_compressor.h | 11 ++------
 include/dwarfs/compression.h      | 46 +++++++++++++++++++++++++++++++
 src/dwarfs/fstypes.cpp            | 10 ++++---
 3 files changed, 54 insertions(+), 13 deletions(-)
 create mode 100644 include/dwarfs/compression.h

diff --git a/include/dwarfs/block_compressor.h b/include/dwarfs/block_compressor.h
index c8c74b24..8184cada 100644
--- a/include/dwarfs/block_compressor.h
+++ b/include/dwarfs/block_compressor.h
@@ -33,19 +33,12 @@
 #include <utility>
 #include <vector>
 
+#include "dwarfs/compression.h"
+
 namespace dwarfs {
 
 class option_map;
 
-// TODO: move this to fstypes.h?
-enum class compression_type : uint8_t {
-  NONE = 0,
-  LZMA = 1,
-  ZSTD = 2,
-  LZ4 = 3,
-  LZ4HC = 4,
-};
-
 class bad_compression_ratio_error : public std::runtime_error {
  public:
   bad_compression_ratio_error()
diff --git a/include/dwarfs/compression.h b/include/dwarfs/compression.h
new file mode 100644
index 00000000..d8f9f9cf
--- /dev/null
+++ b/include/dwarfs/compression.h
@@ -0,0 +1,46 @@
+/* vim:set ts=2 sw=2 sts=2 et: */
+/**
+ * \author     Marcus Holland-Moritz (github@mhxnet.de)
+ * \copyright  Copyright (c) Marcus Holland-Moritz
+ *
+ * This file is part of dwarfs.
+ *
+ * dwarfs is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * dwarfs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with dwarfs.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+// clang-format off
+#define DWARFS_COMPRESSION_TYPE_LIST(DWARFS_COMPRESSION_TYPE, SEPARATOR) \
+  DWARFS_COMPRESSION_TYPE(NONE,   0) SEPARATOR                           \
+  DWARFS_COMPRESSION_TYPE(LZMA,   1) SEPARATOR                           \
+  DWARFS_COMPRESSION_TYPE(ZSTD,   2) SEPARATOR                           \
+  DWARFS_COMPRESSION_TYPE(LZ4,    3) SEPARATOR                           \
+  DWARFS_COMPRESSION_TYPE(LZ4HC,  4)
+// clang-format on
+
+namespace dwarfs {
+
+enum class compression_type : uint8_t {
+#define DWARFS_COMPRESSION_TYPE_ENUMERATION_(name, value) name = value
+#define DWARFS_COMMA_ ,
+  DWARFS_COMPRESSION_TYPE_LIST(DWARFS_COMPRESSION_TYPE_ENUMERATION_,
+                               DWARFS_COMMA_)
+#undef DWARFS_COMPRESSION_TYPE_ENUMERATION_
+#undef DWARFS_COMMA_
+};
+
+} // namespace dwarfs
diff --git a/src/dwarfs/fstypes.cpp b/src/dwarfs/fstypes.cpp
index 93cade0e..992b7941 100644
--- a/src/dwarfs/fstypes.cpp
+++ b/src/dwarfs/fstypes.cpp
@@ -28,6 +28,7 @@
 
 #include <fmt/format.h>
 
+#include "dwarfs/compression.h"
 #include "dwarfs/fstypes.h"
 
 namespace dwarfs {
@@ -44,10 +45,11 @@ const std::map<section_type, std::string_view> sections{
 };
 
 const std::map<compression_type, std::string_view> compressions{
-#define COMPRESSION_TYPE_(x) {compression_type::x, #x}
-    COMPRESSION_TYPE_(NONE), COMPRESSION_TYPE_(LZMA), COMPRESSION_TYPE_(ZSTD),
-    COMPRESSION_TYPE_(LZ4), COMPRESSION_TYPE_(LZ4HC)
-#undef COMPRESSION_TYPE_
+#define DWARFS_COMPRESSION_TYPE_(name, value) {compression_type::name, #name}
+#define DWARFS_COMMA_ ,
+    DWARFS_COMPRESSION_TYPE_LIST(DWARFS_COMPRESSION_TYPE_, DWARFS_COMMA_)
+#undef DWARFS_COMPRESSION_TYPE_
+#undef DWARFS_COMMA_
 };
 
 template <typename HT>