libgit2: provide init_count of the library

A function to provide the initialization count of the library; this is
subject to race conditions but is useful for a naive determination as to
whether the library has been initialized or not.

4 files changed, 31 insertions, 0 deletions

diff --git a/src/libgit2.c b/src/libgit2.c
index e41988c8e..f27c9997d 100644
--- a/src/libgit2.c
+++ b/src/libgit2.c
@@ -90,6 +90,11 @@ int git_libgit2_init(void)
 	return git_runtime_init(init_fns, ARRAY_SIZE(init_fns));
 }
 
+int git_libgit2_init_count(void)
+{
+	return git_runtime_init_count();
+}
+
 int git_libgit2_shutdown(void)
 {
 	return git_runtime_shutdown();
diff --git a/src/libgit2.h b/src/libgit2.h
index 6f92a8318..a898367ae 100644
--- a/src/libgit2.h
+++ b/src/libgit2.h
@@ -7,6 +7,8 @@
 #ifndef INCLUDE_libgit2_h__
 #define INCLUDE_libgit2_h__
 
+extern int git_libgit2_init_count(void);
+
 extern const char *git_libgit2__user_agent(void);
 extern const char *git_libgit2__ssl_ciphers(void);
 
diff --git a/src/runtime.c b/src/runtime.c
index b61c3c4ba..c05dee8b9 100644
--- a/src/runtime.c
+++ b/src/runtime.c
@@ -127,6 +127,21 @@ int git_runtime_init(git_runtime_init_fn init_fns[], size_t cnt)
 	return ret;
 }
 
+int git_runtime_init_count(void)
+{
+	int ret;
+
+	if (init_lock() < 0)
+		return -1;
+
+	ret = git_atomic32_get(&init_count);
+
+	if (init_unlock() < 0)
+		return -1;
+
+	return ret;
+}
+
 int git_runtime_shutdown(void)
 {
 	int ret;
diff --git a/src/runtime.h b/src/runtime.h
index be2e37a60..2cbcafe52 100644
--- a/src/runtime.h
+++ b/src/runtime.h
@@ -28,6 +28,15 @@ typedef void (*git_runtime_shutdown_fn)(void);
  */
 int git_runtime_init(git_runtime_init_fn init_fns[], size_t cnt);
 
+/*
+ * Returns the number of initializations active (the number of calls to
+ * `git_runtime_init` minus the number of calls sto `git_runtime_shutdown`).
+ * If 0, the runtime is not currently initialized.
+ *
+ * @return The number of initializations performed or an error
+ */
+int git_runtime_init_count(void);
+
 /**
  * Shut down the runtime.  If this is the last shutdown call,
  * such that there are no remaining `init` calls, then any