add new vector representation as a library

Author: thestinger

src/libstd/lib.rs

@@ -110,6 +110,7 @@ pub mod char;
 pub mod tuple;
 
 pub mod vec;
+pub mod vec_ng;
 pub mod at_vec;
 pub mod str;
 

src/libstd/rt/global_heap.rs

@@ -52,7 +52,7 @@ pub unsafe fn realloc_raw(ptr: *mut u8, size: uint) -> *mut u8 {
     // `realloc(ptr, 0)` may allocate, but it may also return a null pointer
     // http://pubs.opengroup.org/onlinepubs/9699919799/functions/realloc.html
     if size == 0 {
-        free(ptr);
+        free(ptr as *mut c_void);
         mut_null()
     } else {
         let p = realloc(ptr as *mut c_void, size as size_t);

src/libstd/vec_ng.rs

@@ -0,0 +1,231 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Migrate documentation over from `std::vec` when it is removed.
+#[doc(hidden)];
+
+use prelude::*;
+use container::Container;
+use mem::size_of;
+use cast::{forget, transmute};
+use rt::global_heap::{malloc_raw, realloc_raw};
+use vec::Items;
+use unstable::raw::Slice;
+use ptr::{offset, read_ptr};
+use libc::{free, c_void};
+use unstable::intrinsics::move_val_init;
+
+pub struct Vec<T> {
+    priv len: uint,
+    priv cap: uint,
+    priv ptr: *mut T
+}
+
+impl<T> Vec<T> {
+    #[inline]
+    pub fn new() -> Vec<T> {
+        Vec { len: 0, cap: 0, ptr: 0 as *mut T }
+    }
+
+    pub fn with_capacity(capacity: uint) -> Vec<T> {
+        if capacity == 0 {
+            Vec::new()
+        } else {
+            let size = capacity.checked_mul(&size_of::<T>()).expect("capacity overflow");
+            let ptr = unsafe { malloc_raw(size) };
+            Vec { len: 0, cap: capacity, ptr: ptr as *mut T }
+        }
+    }
+
+    pub fn from_fn(length: uint, op: |uint| -> T) -> Vec<T> {
+        unsafe {
+            let mut xs = Vec::with_capacity(length);
+            while xs.len < length {
+                move_val_init(xs.as_mut_slice().unsafe_mut_ref(xs.len), op(xs.len));
+                xs.len += 1;
+            }
+            xs
+        }
+    }
+}
+
+impl<T: Clone> Vec<T> {
+    pub fn from_elem(length: uint, value: T) -> Vec<T> {
+        unsafe {
+            let mut xs = Vec::with_capacity(length);
+            while xs.len < length {
+                move_val_init(xs.as_mut_slice().unsafe_mut_ref(xs.len), value.clone());
+                xs.len += 1;
+            }
+            xs
+        }
+    }
+}
+
+impl<T> Container for Vec<T> {
+    #[inline]
+    fn len(&self) -> uint {
+        self.len
+    }
+}
+
+impl<T> Vec<T> {
+    #[inline]
+    pub fn capacity(&self) -> uint {
+        self.cap
+    }
+
+    pub fn reserve_exact(&mut self, capacity: uint) {
+        if capacity >= self.len {
+            let size = capacity.checked_mul(&size_of::<T>()).expect("capacity overflow");
+            self.cap = capacity;
+            unsafe {
+                self.ptr = realloc_raw(self.ptr as *mut u8, size) as *mut T;
+            }
+        }
+    }
+
+    pub fn shrink_to_fit(&mut self) {
+        if self.len == 0 {
+            unsafe { free(self.ptr as *mut c_void) };
+            self.cap = 0;
+            self.ptr = 0 as *mut T;
+        } else {
+            unsafe {
+                // Overflow check is unnecessary as the vector is already at least this large.
+                self.ptr = realloc_raw(self.ptr as *mut u8, self.len * size_of::<T>()) as *mut T;
+            }
+            self.cap = self.len;
+        }
+    }
+
+    #[inline]
+    pub fn pop(&mut self) -> Option<T> {
+        if self.len == 0 {
+            None
+        } else {
+            unsafe {
+                self.len -= 1;
+                Some(read_ptr(self.as_slice().unsafe_ref(self.len())))
+            }
+        }
+    }
+
+    #[inline]
+    pub fn push(&mut self, value: T) {
+        if self.len == self.cap {
+            if self.cap == 0 { self.cap += 2 }
+            let old_size = self.cap * size_of::<T>();
+            self.cap = self.cap * 2;
+            let size = old_size * 2;
+            if old_size > size { fail!("capacity overflow") }
+            unsafe {
+                self.ptr = realloc_raw(self.ptr as *mut u8, size) as *mut T;
+            }
+        }
+
+        unsafe {
+            let end = offset(self.ptr as *T, self.len as int) as *mut T;
+            move_val_init(&mut *end, value);
+            self.len += 1;
+        }
+    }
+
+    pub fn truncate(&mut self, len: uint) {
+        unsafe {
+            let mut i = len;
+            // drop any extra elements
+            while i < self.len {
+                read_ptr(self.as_slice().unsafe_ref(i));
+                i += 1;
+            }
+        }
+        self.len = len;
+    }
+
+    #[inline]
+    pub fn as_slice<'a>(&'a self) -> &'a [T] {
+        let slice = Slice { data: self.ptr as *T, len: self.len };
+        unsafe { transmute(slice) }
+    }
+
+    #[inline]
+    pub fn as_mut_slice<'a>(&'a mut self) -> &'a mut [T] {
+        let slice = Slice { data: self.ptr as *T, len: self.len };
+        unsafe { transmute(slice) }
+    }
+
+    #[inline]
+    pub fn move_iter(self) -> MoveItems<T> {
+        unsafe {
+            let iter = transmute(self.as_slice().iter());
+            let ptr = self.ptr as *mut c_void;
+            forget(self);
+            MoveItems { allocation: ptr, iter: iter }
+        }
+    }
+
+    #[inline]
+    pub unsafe fn set_len(&mut self, len: uint) {
+        self.len = len;
+    }
+}
+
+
+#[unsafe_destructor]
+impl<T> Drop for Vec<T> {
+    fn drop(&mut self) {
+        unsafe {
+            for x in self.as_mut_slice().iter() {
+                read_ptr(x);
+            }
+            free(self.ptr as *mut c_void)
+        }
+    }
+}
+
+pub struct MoveItems<T> {
+    priv allocation: *mut c_void, // the block of memory allocated for the vector
+    priv iter: Items<'static, T>
+}
+
+impl<T> Iterator<T> for MoveItems<T> {
+    #[inline]
+    fn next(&mut self) -> Option<T> {
+        unsafe {
+            self.iter.next().map(|x| read_ptr(x))
+        }
+    }
+
+    #[inline]
+    fn size_hint(&self) -> (uint, Option<uint>) {
+        self.iter.size_hint()
+    }
+}
+
+impl<T> DoubleEndedIterator<T> for MoveItems<T> {
+    #[inline]
+    fn next_back(&mut self) -> Option<T> {
+        unsafe {
+            self.iter.next_back().map(|x| read_ptr(x))
+        }
+    }
+}
+
+#[unsafe_destructor]
+impl<T> Drop for MoveItems<T> {
+    fn drop(&mut self) {
+        // destroy the remaining elements
+        for _x in *self {}
+        unsafe {
+            free(self.allocation)
+        }
+    }
+}