Use a single lock in indexing dispatches

Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

Author: jviotti

src/build/build.cc

@@ -124,10 +124,9 @@ auto Build::refresh(const std::filesystem::path &path) -> void {
   this->entries_[path.native()].file_mark = value;
 }
 
-auto Build::track(const std::filesystem::path &path) -> void {
+auto Build::track_unsafe(const std::filesystem::path &path) -> void {
   assert(path.is_absolute());
   const auto &path_string{path.native()};
-  std::unique_lock lock{this->mutex};
   this->entries_[path_string].tracked = true;
   auto parent_key{path_string};
   while (true) {
@@ -147,6 +146,11 @@ auto Build::track(const std::filesystem::path &path) -> void {
   }
 }
 
+auto Build::track(const std::filesystem::path &path) -> void {
+  std::unique_lock lock{this->mutex};
+  this->track_unsafe(path);
+}
+
 auto Build::is_untracked_file(const std::filesystem::path &path) const -> bool {
   std::shared_lock lock{this->mutex};
   const auto match{this->entries_.find(path.native())};

src/build/include/sourcemeta/one/build.h

@@ -10,6 +10,7 @@
 #include <array>         // std::array
 #include <filesystem>    // std::filesystem
 #include <functional>    // std::function, std::reference_wrapper, std::cref
+#include <mutex>         // std::unique_lock
 #include <optional>      // std::optional
 #include <shared_mutex>  // std::shared_mutex, std::shared_lock
 #include <string>        // std::string
@@ -50,7 +51,7 @@ class SOURCEMETA_ONE_BUILD_EXPORT Build {
                 const std::vector<std::filesystem::path> &dependencies)
       -> bool {
     const auto &destination_string{destination.native()};
-    std::shared_lock lock{this->mutex};
+    std::unique_lock lock{this->mutex};
     const auto cached_match{this->entries_.find(destination_string)};
     if (cached_match != this->entries_.end()) {
       const auto &entry{cached_match->second};
@@ -69,8 +70,7 @@ class SOURCEMETA_ONE_BUILD_EXPORT Build {
         }
 
         if (this->dispatch_is_cached(entry, static_dependencies_match)) {
-          lock.unlock();
-          this->track(destination);
+          this->track_unsafe(destination);
           return false;
         }
       }
@@ -107,7 +107,7 @@ class SOURCEMETA_ONE_BUILD_EXPORT Build {
                 const Context &context, const DependencyTypes &...dependencies)
       -> bool {
     const auto &destination_string{destination.native()};
-    std::shared_lock lock{this->mutex};
+    std::unique_lock lock{this->mutex};
     const auto cached_match{this->entries_.find(destination_string)};
     if (cached_match != this->entries_.end()) {
       const auto &entry{cached_match->second};
@@ -131,8 +131,7 @@ class SOURCEMETA_ONE_BUILD_EXPORT Build {
         }
 
         if (this->dispatch_is_cached(entry, static_dependencies_match)) {
-          lock.unlock();
-          this->track(destination);
+          this->track_unsafe(destination);
           return false;
         }
       }
@@ -187,6 +186,7 @@ class SOURCEMETA_ONE_BUILD_EXPORT Build {
                   std::vector<std::filesystem::path> &&static_dependencies,
                   std::vector<std::filesystem::path> &&dynamic_dependencies)
       -> void;
+  auto track_unsafe(const std::filesystem::path &path) -> void;
 
   std::filesystem::path root;
   std::string root_string;