unix,win: add uv_library_shutdown()

Make it possible to explicitly tell libuv to release any resources
it's still holding onto (memory, threads, file descriptors, etc.)

Before this commit, cleanup was performed in various destructors.
This commit centralizes the cleanup logic, enabling the addition of
`uv_library_shutdown()`, but maintains the current observable behavior
of cleaning up when libuv is unloaded by means of `dlclose(3)`.

Fixes: https://github.com/libuv/libuv/issues/2763
PR-URL: https://github.com/libuv/libuv/pull/2764
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/src/uv-common.c b/src/uv-common.c
index 5cb1a8c8..f69a2c1d 100644
--- a/src/uv-common.c
+++ b/src/uv-common.c
@@ -821,3 +821,19 @@ void uv_free_cpu_info(uv_cpu_info_t* cpu_infos, int count) {
 
   uv__free(cpu_infos);
 }
+
+
+#ifdef __GNUC__  /* Also covers __clang__ and __INTEL_COMPILER. */
+__attribute__((destructor))
+#endif
+void uv_library_shutdown(void) {
+  static int was_shutdown;
+
+  if (was_shutdown)
+    return;
+
+  uv__process_title_cleanup();
+  uv__signal_cleanup();
+  uv__threadpool_cleanup();
+  was_shutdown = 1;
+}