Format

src/header/_oldlib/mallocnull.rs

@@ -0,0 +1,46 @@
+use core::mem;
+use libc::{c_void, size_t};
+
+/// Malloc memory if pointer is null, and free on drop
+pub struct MallocNull<T> {
+    value: *mut T,
+    free_on_drop: bool
+}
+
+impl<T> MallocNull<T> {
+    pub fn new(ptr: *mut T, size: usize) -> MallocNull<T> {
+        if ptr.is_null() {
+            MallocNull {
+                value: unsafe { ::malloc(size as size_t) as *mut T },
+                free_on_drop: true
+            }
+	    } else {
+            MallocNull {
+                value: ptr,
+                free_on_drop: false
+            }
+        }
+    }
+    
+    pub fn into_raw(self) -> *mut T {
+        let ptr = self.value;
+        mem::forget(self);
+        ptr
+    }
+
+    pub fn as_ptr(&self) -> *const T {
+        self.value
+    }
+
+    pub fn as_mut_ptr(&self) -> *mut T {
+        self.value
+    }
+}
+
+impl<T> Drop for MallocNull<T> {
+    fn drop(&mut self) {
+        if self.free_on_drop {
+            unsafe { ::free(self.value as *mut c_void) };
+        }
+    }
+}