commit fdef30085a12aa04de8c9b47a40963ca5aa23d49
author Cameron Dale <camrdale@google.com> Thu Dec 12 18:38:05 2019 +0000
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> Thu Dec 12 18:38:05 2019 +0000
tree 1c70a91c542d53d31855f57b0be5b79dde01d9d4
parent fafaa55964f96281317bb2ed2156586aac2036dc

Remove a use of absl/synchronization from Cobalt.

absl/synchronization is banned in Fuchsia:
https://fuchsia.googlesource.com/fuchsia/+/master/docs/development/languages/c-cpp/library_restrictions.md#third_party_absl_cpp

Replace it with src/lib/util/protected_fields.h instead.

Change-Id: Ic41bce7c63c5ee66b2e772247e66f0cf9af50001

src/bin/test_app/BUILD.gn

diff --git a/src/bin/test_app/BUILD.gn b/src/bin/test_app/BUILD.gn
index 4ec99b6..5a557c3 100644
--- a/src/bin/test_app/BUILD.gn
+++ b/src/bin/test_app/BUILD.gn
@@ -63,7 +63,6 @@
     "$cobalt_root/src/bin/test_app/test_registry",
     "$cobalt_root/src/logger:logger_test_utils",
     "$cobalt_root/src/logger:project_context_factory",
-    "//third_party/abseil-cpp/absl/synchronization",
     "//third_party/gflags",
     "//third_party/googletest:gtest",
     "//third_party/tink/cc/util:status",

src/system_data/BUILD.gn

diff --git a/src/system_data/BUILD.gn b/src/system_data/BUILD.gn
index 82e2094..6c8a43b 100644
--- a/src/system_data/BUILD.gn
+++ b/src/system_data/BUILD.gn
@@ -33,8 +33,8 @@
   configs += [ "$cobalt_root:cobalt_config" ]
   deps = [
     "$cobalt_root/src:logging",
+    "$cobalt_root/src/lib/util:protected_fields",
     "//third_party/abseil-cpp",
-    "//third_party/abseil-cpp/absl/synchronization",
   ]
   public_deps = [
     "$cobalt_root/src/pb",

src/system_data/system_data.h

diff --git a/src/system_data/system_data.h b/src/system_data/system_data.h
index 28e8b35..d1d3d4d 100644
--- a/src/system_data/system_data.h
+++ b/src/system_data/system_data.h
@@ -11,9 +11,9 @@
 #include <utility>
 #include <vector>
 
+#include "src/lib/util/protected_fields.h"
 #include "src/pb/observation_batch.pb.h"
 #include "src/registry/metric_definition.pb.h"
-#include "third_party/abseil-cpp/absl/synchronization/mutex.h"
 
 namespace cobalt::system_data {
 
@@ -64,18 +64,18 @@
   ~SystemData() override = default;
 
   // Returns a vector with all experiments the system has a notion of.
-  const std::vector<Experiment>& experiments() const override LOCKS_EXCLUDED(experiments_mutex_) {
-    absl::ReaderMutexLock lock(&experiments_mutex_);
-    return experiments_;
+  const std::vector<Experiment>& experiments() const override {
+    auto unprotected_experiments = protected_experiments_.const_lock();
+    return unprotected_experiments->experiments;
   }
 
   // Returns the SystemProfile for the current system.
   const SystemProfile& system_profile() const override { return system_profile_; }
 
   // Resets the experiment state to the one provided.
-  void SetExperimentState(std::vector<Experiment> experiments) LOCKS_EXCLUDED(experiments_mutex_) {
-    absl::WriterMutexLock lock(&experiments_mutex_);
-    experiments_ = std::move(experiments);
+  void SetExperimentState(std::vector<Experiment> experiments) {
+    auto unprotected_experiments = protected_experiments_.lock();
+    unprotected_experiments->experiments = std::move(experiments);
   }
 
   // Resets the current channel value.
@@ -92,8 +92,10 @@
   void PopulateSystemProfile();
 
   SystemProfile system_profile_;
-  mutable absl::Mutex experiments_mutex_;
-  std::vector<Experiment> experiments_ GUARDED_BY(experiments_mutex_);
+  struct UnprotectedExperiments {
+    std::vector<Experiment> experiments;
+  };
+  util::RWProtectedFields<UnprotectedExperiments> protected_experiments_;
   ReleaseStage release_stage_;
 };