memcheck: fix race in libgit2...

...caused by incorrectly setting and resetting the library internal
state and the misuse of pthreads in libgit2.

Normally, git_libgit2_init and git_libgit2_shutdown should span the
life of a worker thread in order to be safely used. However, due to
an incorrect implementation of libgit2's threadstate with pthreads,
on unix systems there is a race condition.

Until the use of pthread_key_t is corrected in libgit2, we need to
apply a workaround by always ensuring that the main thread is the
first thread reaching the GitContext constructor.

4 files changed, 24 insertions, 2 deletions

diff --git a/test/TARGETS b/test/TARGETS
index 9e9c20eb..8fb612ec 100644
--- a/test/TARGETS
+++ b/test/TARGETS
@@ -2,7 +2,11 @@
   { "type": ["@", "rules", "CC", "library"]
   , "name": ["catch-main"]
   , "srcs": ["main.cpp"]
-  , "deps": [["@", "catch2", "", "catch2"], ["test/utils", "log_config"]]
+  , "deps":
+    [ ["@", "catch2", "", "catch2"]
+    , ["test/utils", "log_config"]
+    , ["src/buildtool/file_system", "git_context"]
+    ]
   , "stage": ["test"]
   }
 , "TESTS":
diff --git a/test/main.cpp b/test/main.cpp
index c93583f2..bb431de2 100644
--- a/test/main.cpp
+++ b/test/main.cpp
@@ -13,9 +13,19 @@
 // limitations under the License.
 
 #include "catch2/catch_session.hpp"
+#include "src/buildtool/file_system/git_context.hpp"
 #include "test/utils/logging/log_config.hpp"
 
 auto main(int argc, char* argv[]) -> int {
     ConfigureLogging();
+
+    /**
+     * The current implementation of libgit2 uses pthread_key_t incorrectly
+     * on POSIX systems to handle thread-specific data, which requires us to
+     * explicitly make sure the main thread is the first one to call
+     * git_libgit2_init. Future versions of libgit2 will hopefully fix this.
+     */
+    GitContext::Create();
+
     return Catch::Session().run(argc, argv);
 }
diff --git a/test/other_tools/git_operations/git_config_run.test.cpp b/test/other_tools/git_operations/git_config_run.test.cpp
index 8ffd744a..956b8926 100644
--- a/test/other_tools/git_operations/git_config_run.test.cpp
+++ b/test/other_tools/git_operations/git_config_run.test.cpp
@@ -45,7 +45,7 @@ auto main(int argc, char* argv[]) -> int {
         ConfigureLogging();
 
         // start a git context, needed to read in the config file
-        GitContext context{};
+        GitContext::Create();
 
         // handle args
         if (argc < 3) {
diff --git a/test/utils/remote_execution/main-remote-execution.cpp b/test/utils/remote_execution/main-remote-execution.cpp
index 7dd48d92..49b0b617 100644
--- a/test/utils/remote_execution/main-remote-execution.cpp
+++ b/test/utils/remote_execution/main-remote-execution.cpp
@@ -86,6 +86,14 @@ auto main(int argc, char* argv[]) -> int {
         return EXIT_FAILURE;
     }
 
+    /**
+     * The current implementation of libgit2 uses pthread_key_t incorrectly
+     * on POSIX systems to handle thread-specific data, which requires us to
+     * explicitly make sure the main thread is the first one to call
+     * git_libgit2_init. Future versions of libgit2 will hopefully fix this.
+     */
+    GitContext::Create();
+
     int result = Catch::Session().run(argc, argv);
 
     // valgrind fails if we terminate before grpc's async shutdown threads exit