Free cache memory once it's no longer used.

Doesn't slow down empty build times measurably, and
saves some memory on non-empty builds.

3 files changed, 23 insertions, 8 deletions

diff --git a/src/disk_interface.cc b/src/disk_interface.cc
index cd99915..ff86ed1 100644
--- a/src/disk_interface.cc
+++ b/src/disk_interface.cc
@@ -230,3 +230,19 @@ int RealDiskInterface::RemoveFile(const string& path) {
     return 0;
   }
 }
+
+void RealDiskInterface::AllowCache(bool allow) {
+#ifdef _WIN32
+  use_cache_ = allow;
+  if (!use_cache_)
+    ClearCache();
+#endif
+}
+
+void RealDiskInterface::ClearCache() {
+#ifdef _WIN32
+  for (Cache::iterator it = cache_.begin(), end = cache_.end(); it != end; ++it)
+    delete it->second;
+  cache_.clear();
+#endif
+}
diff --git a/src/disk_interface.h b/src/disk_interface.h
index bb40dc9..40c24b6 100644
--- a/src/disk_interface.h
+++ b/src/disk_interface.h
@@ -61,7 +61,7 @@ struct RealDiskInterface : public DiskInterface {
                       , use_cache_(false)
 #endif
                       {}
-  virtual ~RealDiskInterface() {}
+  virtual ~RealDiskInterface() { ClearCache(); }
   virtual TimeStamp Stat(const string& path);
   virtual bool MakeDir(const string& path);
   virtual bool WriteFile(const string& path, const string& contents);
@@ -70,6 +70,9 @@ struct RealDiskInterface : public DiskInterface {
 
   /// Whether to print on errors.  Used to make a test quieter.
   bool quiet_;
+
+  /// Whether stat information can be cached.
+  void AllowCache(bool allow);
 #ifdef _WIN32
   /// Whether stat information can be cached.
   bool use_cache_;
@@ -80,6 +83,7 @@ struct RealDiskInterface : public DiskInterface {
   typedef map<string, DirCache*> Cache;
   Cache cache_;
 #endif
+  void ClearCache();
 };
 
 #endif  // NINJA_DISK_INTERFACE_H_
diff --git a/src/ninja.cc b/src/ninja.cc
index cace2a0..eedfec0 100644
--- a/src/ninja.cc
+++ b/src/ninja.cc
@@ -889,10 +889,7 @@ int NinjaMain::RunBuild(int argc, char** argv) {
     return 1;
   }
 
-#ifdef _WIN32
-  if (g_experimental_win_statcache)
-    disk_interface_.use_cache_ = true;
-#endif
+  disk_interface_.AllowCache(g_experimental_win_statcache);
 
   Builder builder(&state_, config_, &build_log_, &deps_log_, &disk_interface_);
   for (size_t i = 0; i < targets.size(); ++i) {
@@ -907,10 +904,8 @@ int NinjaMain::RunBuild(int argc, char** argv) {
     }
   }
 
-#ifdef _WIN32
   // Make sure restat rules do not see stale timestamps.
-  disk_interface_.use_cache_ = false;
-#endif
+  disk_interface_.AllowCache(false);
 
   if (builder.AlreadyUpToDate()) {
     printf("ninja: no work to do.\n");