Only use the stack_alloc helper for multiple pointers

Author: eregon

lib/truffle/socket/truffle/foreign.rb

@@ -1,3 +1,5 @@
+# truffleruby_primitives: true
+
 # Copyright (c) 2013, Brian Shirai
 # All rights reserved.
 #
@@ -95,26 +97,25 @@ module Foreign
       attach_function :freeifaddrs, [:pointer], :void
 
       def self.bind(descriptor, sockaddr)
-        sockaddr_p = Truffle::FFI::Pool.stack_alloc(:char, sockaddr.bytesize)
+        sockaddr_p = Primitive.io_thread_buffer_allocate(sockaddr.bytesize)
         begin
           sockaddr_p.write_bytes(sockaddr)
           _bind(descriptor, sockaddr_p, sockaddr.bytesize)
         ensure
-          Truffle::FFI::Pool.stack_free(sockaddr_p)
+          Primitive.io_thread_buffer_free(sockaddr_p)
         end
       end
 
       def self.connect(descriptor, sockaddr)
         sockaddr = Socket.coerce_to_string(sockaddr)
 
-        sockaddr_p = Truffle::FFI::Pool.stack_alloc(:char, sockaddr.bytesize)
-
+        sockaddr_p = Primitive.io_thread_buffer_allocate(sockaddr.bytesize)
         begin
           sockaddr_p.write_bytes(sockaddr)
 
           _connect(descriptor, sockaddr_p, sockaddr.bytesize)
         ensure
-          Truffle::FFI::Pool.stack_free(sockaddr_p)
+          Primitive.io_thread_buffer_free(sockaddr_p)
         end
       end
 
@@ -143,10 +144,10 @@ def self.getaddrinfo(host, service = nil, family = nil, socktype = nil,
         hints[:ai_protocol] = protocol || 0
         hints[:ai_flags]    = flags || 0
 
-        res_p = Truffle::FFI::Pool.stack_alloc(:pointer, 1)
+        res_p = Primitive.io_thread_buffer_allocate(Primitive.pointer_find_type_size(:pointer))
 
         res_p.clear
-        err   = _getaddrinfo(host, service, hints.pointer, res_p)
+        err = _getaddrinfo(host, service, hints.pointer, res_p)
 
         raise SocketError, gai_strerror(err) unless err == 0
 
@@ -183,7 +184,7 @@ def self.getaddrinfo(host, service = nil, family = nil, socktype = nil,
 
           # Be sure to feed a legit pointer to freeaddrinfo
           freeaddrinfo(ptr) unless ptr.null?
-          Truffle::FFI::Pool.stack_free(res_p)
+          Primitive.io_thread_buffer_free(res_p)
         end
       end
 
@@ -283,7 +284,7 @@ def self.pack_sockaddr_in(host, port, family = ::Socket::AF_UNSPEC,
           host = '0.0.0.0'
         end
 
-        res_p = Truffle::FFI::Pool.stack_alloc(:pointer, 1)
+        res_p = Primitive.io_thread_buffer_allocate(Primitive.pointer_find_type_size(:pointer))
         res_p.clear
 
         err = _getaddrinfo(host, port.to_s, hints.pointer, res_p)
@@ -302,7 +303,7 @@ def self.pack_sockaddr_in(host, port, family = ::Socket::AF_UNSPEC,
           ptr = res_p.read_pointer
 
           freeaddrinfo(ptr) unless ptr.null?
-          Truffle::FFI::Pool.stack_free(res_p)
+          Primitive.io_thread_buffer_free(res_p)
         end
       end
 
@@ -328,7 +329,7 @@ def self.getpeereid(*)
       end
 
       def self.socketpair(family, type, protocol)
-        pointer = Truffle::FFI::Pool.stack_alloc(:int, 2)
+        pointer = Primitive.io_thread_buffer_allocate(Primitive.pointer_find_type_size(:int) * 2)
         begin
           pointer.clear
           status = _socketpair(family, type, protocol, pointer)
@@ -337,7 +338,7 @@ def self.socketpair(family, type, protocol)
 
           pointer.read_array_of_int(2)
         ensure
-          Truffle::FFI::Pool.stack_free(pointer)
+          Primitive.io_thread_buffer_free(pointer)
         end
       end
 
@@ -373,7 +374,7 @@ def self.ip_to_bytes(family, address)
           address = address[0...i]
         end
 
-        pointer = Truffle::FFI::Pool.stack_alloc(:pointer, size)
+        pointer = Primitive.io_thread_buffer_allocate(Primitive.pointer_find_type_size(:pointer) * size)
 
         begin
           status = inet_pton(family, address, pointer)
@@ -382,7 +383,7 @@ def self.ip_to_bytes(family, address)
 
           pointer.get_array_of_uchar(0, size)
         ensure
-          Truffle::FFI::Pool.stack_free(pointer)
+          Primitive.io_thread_buffer_free(pointer)
         end
       end
     end

src/main/ruby/truffleruby/core/truffle/ffi/pointer.rb

@@ -266,7 +266,8 @@ def self.from_string(str)
   end
 
   class Pool
-
+    # Use Primitive.io_thread_buffer_allocate(Primitive.pointer_find_type_size(:type) * n)
+    # instead for a single pointer. This method always returns an Array of FFI::Pointer.
     def self.stack_alloc(*args)
       total_length = 0
       offsets = []
@@ -286,10 +287,10 @@ def self.stack_alloc(*args)
         total_length += length
       end
       buffer = Primitive.io_thread_buffer_allocate(total_length)
-      pointers = offsets.map { |offset, length| buffer.slice(offset, length) }
-      pointers.size == 1 ? pointers[0] : pointers
+      offsets.map { |offset, length| buffer.slice(offset, length) }
     end
 
+    # The argument is the first pointer returned by #stack_alloc
     def self.stack_free(pointer)
       Primitive.io_thread_buffer_free(pointer)
     end