Store each FFI::Function in it's own instance variabe in the module to be attached

This allows to freeze the FFI::Function immediately, so that it is shareable by Ractor without the need to freeze the module explicit.
To make it shareable the typedef hash used for variadic functions is duplicated and made frozen.

This creates a small compatibility issue:
Only typedefs defined above the variadic function can be used by that function.
If a typedef is created after the definition of the variadic function, then this typedef can no longer be used as parameter to that variadic function.

Also fix the retrieval of simple (non-struct) global variables per #attached_variables.

Closes #975

1 files changed, 17 insertions, 17 deletions

diff --git a/lib/ffi/library.rb b/lib/ffi/library.rb
index 5656b2d..e681b3e 100644
--- a/lib/ffi/library.rb
+++ b/lib/ffi/library.rb
@@ -209,7 +209,7 @@ module FFI
             end
             raise LoadError unless function
 
-            invokers << if arg_types.length > 0 && arg_types[arg_types.length - 1] == FFI::NativeType::VARARGS
+            invokers << if arg_types[-1] == FFI::NativeType::VARARGS
               VariadicInvoker.new(function, arg_types, find_type(ret_type), options)
 
             else
@@ -295,10 +295,9 @@ module FFI
         # If it is a global struct, just attach directly to the pointer
         s = s = type.new(address) # Assigning twice to suppress unused variable warning
         self.module_eval <<-code, __FILE__, __LINE__
-          @ffi_gvars = {} unless defined?(@ffi_gvars)
-          @ffi_gvars[#{mname.inspect}] = s
+          @ffi_gsvar_#{mname} = s
           def self.#{mname}
-            @ffi_gvars[#{mname.inspect}]
+            @ffi_gsvar_#{mname}
           end
         code
 
@@ -310,13 +309,12 @@ module FFI
         # Attach to this module as mname/mname=
         #
         self.module_eval <<-code, __FILE__, __LINE__
-          @ffi_gvars = {} unless defined?(@ffi_gvars)
-          @ffi_gvars[#{mname.inspect}] = s
+          @ffi_gvar_#{mname} = s
           def self.#{mname}
-            @ffi_gvars[#{mname.inspect}][:gvar]
+            @ffi_gvar_#{mname}[:gvar]
           end
           def self.#{mname}=(value)
-            @ffi_gvars[#{mname.inspect}][:gvar] = value
+            @ffi_gvar_#{mname}[:gvar] = value
           end
         code
 
@@ -543,18 +541,20 @@ module FFI
     end
 
     def attached_functions
-      @ffi_functions || {}
-    end
-
-    def attached_variables
-      (@ffi_gvars || {}).map do |name, gvar|
-        [name, gvar.class]
+      instance_variables.grep(/\A@ffi_function_(.*)/) do |m|
+        [$1, instance_variable_get(m)]
       end.to_h
     end
 
-    def freeze
-      super
-      FFI.make_shareable(@ffi_functions)
+    def attached_variables
+      (
+        instance_variables.grep(/\A@ffi_gsvar_(.*)/) do |m|
+          [$1, instance_variable_get(m).class]
+        end +
+        instance_variables.grep(/\A@ffi_gvar_(.*)/) do |m|
+          [$1, instance_variable_get(m).layout[:gvar].type]
+        end
+      ).to_h
     end
   end
 end