From: Joel Rosdahl <joel@rosdahl.net>
Date: Thu, 27 Aug 2020 08:35:59 +0000 (+0200)
Subject: Support passing level 0 to “ccache -X” to use default level
X-Git-Tag: v4.0~162
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2bb90086cf43ce88c00bc87f36b7b3bc1f837277;p=thirdparty%2Fccache.git

Support passing level 0 to “ccache -X” to use default level
---

diff --git a/src/ZstdCompressor.cpp b/src/ZstdCompressor.cpp
index e1fa46d0e..4e054942a 100644
--- a/src/ZstdCompressor.cpp
+++ b/src/ZstdCompressor.cpp
@@ -23,13 +23,11 @@
 
 using Logging::log;
 
-const uint8_t k_default_zstd_compression_level = 1;
-
 ZstdCompressor::ZstdCompressor(FILE* stream, int8_t compression_level)
   : m_stream(stream), m_zstd_stream(ZSTD_createCStream())
 {
   if (compression_level == 0) {
-    compression_level = k_default_zstd_compression_level;
+    compression_level = default_compression_level;
     log("Using default compression level {}", compression_level);
   }
 
diff --git a/src/ZstdCompressor.hpp b/src/ZstdCompressor.hpp
index 3c1203235..58ca45342 100644
--- a/src/ZstdCompressor.hpp
+++ b/src/ZstdCompressor.hpp
@@ -1,4 +1,4 @@
-// Copyright (C) 2019 Joel Rosdahl and other contributors
+// Copyright (C) 2019-2020 Joel Rosdahl and other contributors
 //
 // See doc/AUTHORS.adoc for a complete list of contributors.
 //
@@ -40,6 +40,8 @@ public:
   void write(const void* data, size_t count) override;
   void finalize() override;
 
+  constexpr static uint8_t default_compression_level = 1;
+
 private:
   FILE* m_stream;
   ZSTD_CStream* m_zstd_stream;
diff --git a/src/ccache.cpp b/src/ccache.cpp
index c59f3fc95..c9e8ec82e 100644
--- a/src/ccache.cpp
+++ b/src/ccache.cpp
@@ -2411,22 +2411,21 @@ handle_main_options(int argc, const char* const* argv)
 
     case 'X': // --recompress
     {
-      int level;
+      optional<int8_t> wanted_level;
       if (arg == "uncompressed") {
-        level = 0;
+        wanted_level = nullopt;
       } else {
-        level = Util::parse_int(arg);
+        int level = Util::parse_int(arg);
         if (level < -128 || level > 127) {
           throw Error("compression level must be between -128 and 127");
         }
-        if (level == 0) {
-          level = ctx.config.compression_level();
-        }
+        wanted_level = level;
       }
 
       ProgressBar progress_bar("Recompressing...");
-      compress_recompress(
-        ctx, level, [&](double progress) { progress_bar.update(progress); });
+      compress_recompress(ctx, wanted_level, [&](double progress) {
+        progress_bar.update(progress);
+      });
       break;
     }
 
diff --git a/src/compress.cpp b/src/compress.cpp
index ebf8105a8..d05127e72 100644
--- a/src/compress.cpp
+++ b/src/compress.cpp
@@ -27,6 +27,7 @@
 #include "Result.hpp"
 #include "StdMakeUnique.hpp"
 #include "ThreadPool.hpp"
+#include "ZstdCompressor.hpp"
 #include "manifest.hpp"
 #include "stats.hpp"
 
@@ -36,6 +37,7 @@
 #include <thread>
 
 using Logging::log;
+using nonstd::optional;
 
 namespace {
 
@@ -154,29 +156,31 @@ recompress_file(Context& ctx,
                 RecompressionStatistics& statistics,
                 const std::string& stats_file,
                 const CacheFile& cache_file,
-                int8_t level)
+                optional<int8_t> level)
 {
   auto file = open_file(cache_file.path(), "rb");
   auto reader = create_reader(cache_file, file.get());
 
-  int8_t current_level = reader->compression_type() == Compression::Type::none
-                           ? 0
-                           : reader->compression_level();
   auto old_stat = Stat::stat(cache_file.path(), Stat::OnError::log);
   uint64_t content_size = reader->content_size();
+  int8_t wanted_level =
+    level ? (*level == 0 ? ZstdCompressor::default_compression_level : *level)
+          : 0;
 
-  if (current_level == level) {
+  if (reader->compression_level() == wanted_level) {
     statistics.update(content_size, old_stat.size(), old_stat.size(), 0);
     return;
   }
 
-  log("Recompressing {} to level {}", cache_file.path(), level);
+  log("Recompressing {} to {}",
+      cache_file.path(),
+      level ? fmt::format("level {}", wanted_level) : "uncompressed");
   AtomicFile atomic_new_file(cache_file.path(), AtomicFile::Mode::binary);
-  auto writer = create_writer(atomic_new_file.stream(),
-                              *reader,
-                              level == 0 ? Compression::Type::none
-                                         : Compression::Type::zstd,
-                              level);
+  auto writer =
+    create_writer(atomic_new_file.stream(),
+                  *reader,
+                  level ? Compression::Type::zstd : Compression::Type::none,
+                  wanted_level);
 
   char buffer[READ_BUFFER_SIZE];
   size_t bytes_left = reader->payload_size();
@@ -277,7 +281,7 @@ compress_stats(const Config& config,
 
 void
 compress_recompress(Context& ctx,
-                    int8_t level,
+                    optional<int8_t> level,
                     const Util::ProgressReceiver& progress_receiver)
 {
   const size_t threads = std::thread::hardware_concurrency();
diff --git a/src/compress.hpp b/src/compress.hpp
index 645f62943..91eb04d1b 100644
--- a/src/compress.hpp
+++ b/src/compress.hpp
@@ -1,4 +1,4 @@
-// Copyright (C) 2019 Joel Rosdahl and other contributors
+// Copyright (C) 2019-2020 Joel Rosdahl and other contributors
 //
 // See doc/AUTHORS.adoc for a complete list of contributors.
 //
@@ -22,7 +22,9 @@
 
 #include "Util.hpp"
 
-struct Confix;
+#include "third_party/nonstd/optional.hpp"
+
+class Config;
 class Context;
 
 void compress_stats(const Config& config,
@@ -32,9 +34,9 @@ void compress_stats(const Config& config,
 //
 // Arguments:
 // - ctx: The context.
-// - level: Target compression level (positive or negative value), or 0 for no
-//   compression.
+// - level: Target compression level (positive or negative value for actual
+//   level, 0 for default level and nonstd::nullopt for no compression).
 // - progress_receiver: Function that will be called for progress updates.
 void compress_recompress(Context& ctx,
-                         int8_t level,
+                         nonstd::optional<int8_t> level,
                          const Util::ProgressReceiver& progress_receiver);