simplify Valgrind wrapper

src/debug/mod.rs

@@ -1,27 +1,21 @@
 // This file is part of libfringe, a low-level green threading library.
 // Copyright (c) 2015, edef <edef@edef.eu>
 // See the LICENSE file included in this distribution.
-use stack;
+pub use self::imp::*;
 
-mod valgrind;
+#[cfg(feature = "valgrind")]
+#[path = "valgrind/mod.rs"]
+mod imp;
 
-#[derive(Debug)]
-pub struct StackId(valgrind::stack_id_t);
-
-impl StackId {
-  #[inline(always)]
-  pub fn register<Stack: stack::Stack>(stack: &mut Stack) -> StackId {
-    StackId(unsafe {
-      valgrind::stack_register(stack.limit(), stack.top())
-    })
-  }
-}
-
-impl Drop for StackId {
-  #[inline(always)]
-  fn drop(&mut self) {
-    unsafe {
-      valgrind::stack_deregister(self.0)
+#[cfg(not(feature = "valgrind"))]
+mod imp {
+  use stack;
+  #[derive(Debug)]
+  pub struct StackId;
+  /// No-op since no valgrind
+  impl StackId {
+    pub unsafe fn register<Stack: stack::Stack>(_stack: &mut Stack) -> StackId {
+      StackId
     }
   }
 }

src/debug/valgrind/mod.rs

@@ -1,17 +1,44 @@
 // This file is part of libfringe, a low-level green threading library.
 // Copyright (c) 2015, edef <edef@edef.eu>
 // See the LICENSE file included in this distribution.
-pub use self::imp::*;
+#![allow(non_camel_case_types)]
+//! In order for Valgrind to keep track of stack overflows and such, it needs
+//! a little help. That help unfortunately comes in the form of a set of C
+//! macros. Calling out to un-inlineable C code for this is pointlessly slow,
+//! but that's the way it is for now.
+use stack;
 
-#[cfg(feature = "valgrind")]
-#[path = "native.rs"]
-mod imp;
+pub type stack_id_t = u32;
+extern "C" {
+  #[link_name = "valgrind_stack_register"]
+  /// Register a stack with Valgrind. Returns an integer ID that can
+  /// be used to deregister the stack when it's deallocated.
+  /// `start < end`.
+  pub fn stack_register(start: *const u8, end: *const u8) -> stack_id_t;
 
-#[cfg(not(feature = "valgrind"))]
-mod imp {
-  //! Stub for the Valgrind functions
-  #![allow(non_camel_case_types)]
-  pub type stack_id_t = ();
-  pub unsafe fn stack_register(_start: *const u8, _end: *const u8) -> stack_id_t {}
-  pub unsafe fn stack_deregister(_id: stack_id_t) {}
+  #[link_name = "valgrind_stack_deregister"]
+  /// Deregister a stack from Valgrind. Takes the integer ID that was returned
+  /// on registration.
+  pub fn stack_deregister(id: stack_id_t);
+}
+
+#[derive(Debug)]
+pub struct StackId(stack_id_t);
+
+impl StackId {
+  #[inline(always)]
+  pub fn register<Stack: stack::Stack>(stack: &mut Stack) -> StackId {
+    StackId(unsafe {
+      stack_register(stack.limit(), stack.top())
+    })
+  }
+}
+
+impl Drop for StackId {
+  #[inline(always)]
+  fn drop(&mut self) {
+    unsafe {
+      stack_deregister(self.0)
+    }
+  }
 }

src/debug/valgrind/native.rs

@@ -1,22 +0,0 @@
-// This file is part of libfringe, a low-level green threading library.
-// Copyright (c) 2015, edef <edef@edef.eu>
-// See the LICENSE file included in this distribution.
-#![allow(non_camel_case_types)]
-//! In order for Valgrind to keep track of stack overflows and such, it needs
-//! a little help. That help unfortunately comes in the form of a set of C
-//! macros. Calling out to un-inlineable C code for this is pointlessly slow,
-//! but that's the way it is for now.
-
-pub type stack_id_t = u32;
-extern "C" {
-  #[link_name = "valgrind_stack_register"]
-  /// Register a stack with Valgrind. Returns an integer ID that can
-  /// be used to deregister the stack when it's deallocated.
-  /// `start < end`.
-  pub fn stack_register(start: *const u8, end: *const u8) -> stack_id_t;
-
-  #[link_name = "valgrind_stack_deregister"]
-  /// Deregister a stack from Valgrind. Takes the integer ID that was returned
-  /// on registration.
-  pub fn stack_deregister(id: stack_id_t);
-}