commit 276add0b5c160fd8076cd67b47b5898d7d955400
author zhangskz <89936743+zhangskz@users.noreply.github.com> Tue Mar 08 12:05:34 2022 -0500
committer GitHub <noreply@github.com> Tue Mar 08 12:05:34 2022 -0500
tree dafc37d174a0ccf440567817d42e272cb8a21c59
parent 1cec8031826622c542dfd126ac2df37e68715e51

Add ruby_upb_alloc using xrealloc/xfree so Ruby GC is aware of allocated memory for Arenas. (#9586)

* Add ruby-specific upb_alloc using xrealloc/xfree for use in Arena_alloc so Ruby GC is aware of allocated memory.
* Add RB_GC_GUARD to DescriptorPool_add_serialized_file  to ensure ruby does not aggressively garbage collect arena_rb due to lack of references.

ruby/ext/google/protobuf_c/defs.c

diff --git a/ruby/ext/google/protobuf_c/defs.c b/ruby/ext/google/protobuf_c/defs.c
index aaa8b4d..3bd18e8 100644
--- a/ruby/ext/google/protobuf_c/defs.c
+++ b/ruby/ext/google/protobuf_c/defs.c
@@ -159,6 +159,7 @@
     rb_raise(cTypeError, "Unable to build file to DescriptorPool: %s",
              upb_Status_ErrorMessage(&status));
   }
+  RB_GC_GUARD(arena_rb);
   return get_filedef_obj(_self, filedef);
 }
 

ruby/ext/google/protobuf_c/protobuf.c

diff --git a/ruby/ext/google/protobuf_c/protobuf.c b/ruby/ext/google/protobuf_c/protobuf.c
index 4d3e1a5..2135cca 100644
--- a/ruby/ext/google/protobuf_c/protobuf.c
+++ b/ruby/ext/google/protobuf_c/protobuf.c
@@ -193,9 +193,20 @@
     .flags = RUBY_TYPED_FREE_IMMEDIATELY,
 };
 
+static void* ruby_upb_allocfunc(upb_alloc* alloc, void* ptr, size_t oldsize, size_t size) {
+  if (size == 0) {
+    xfree(ptr);
+    return NULL;
+  } else {
+    return xrealloc(ptr, size);
+  }
+}
+
+upb_alloc ruby_upb_alloc = {&ruby_upb_allocfunc};
+
 static VALUE Arena_alloc(VALUE klass) {
   Arena *arena = ALLOC(Arena);
-  arena->arena = upb_Arena_New();
+  arena->arena = upb_Arena_Init(NULL, 0, &ruby_upb_alloc);
   arena->pinned_objs = Qnil;
   return TypedData_Wrap_Struct(klass, &Arena_type, arena);
 }