Introduce Cosmopolitan Templates Library (CTL)

ctl/vector.h

@@ -0,0 +1,242 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=c++ ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef COSMOPOLITAN_CTL_OPTIONAL_H_
+#define COSMOPOLITAN_CTL_OPTIONAL_H_
+#include <__utility/forward.h>
+#include <__utility/move.h>
+#include <__utility/swap.h>
+
+template<typename T>
+struct Vector
+{
+    size_t n = 0;
+    size_t c = 0;
+    T* p = nullptr;
+
+    using iterator = T*;
+    using const_iterator = const T*;
+
+    Vector() = default;
+
+    ~Vector()
+    {
+        delete[] p;
+    }
+
+    Vector(const Vector& other)
+    {
+        n = other.n;
+        c = other.c;
+        p = new T[c];
+        for (size_t i = 0; i < n; ++i)
+            new (&p[i]) T(other.p[i]);
+    }
+
+    Vector(Vector&& other) noexcept
+    {
+        n = other.n;
+        c = other.c;
+        p = other.p;
+        other.n = 0;
+        other.c = 0;
+        other.p = nullptr;
+    }
+
+    explicit Vector(size_t count, const T& value = T())
+    {
+        n = count;
+        c = count;
+        p = new T[c];
+        for (size_t i = 0; i < n; ++i)
+            new (&p[i]) T(value);
+    }
+
+    Vector& operator=(const Vector& other)
+    {
+        if (this != &other) {
+            T* newData = new T[other.c];
+            for (size_t i = 0; i < other.n; ++i) {
+                newData[i] = other.p[i];
+            }
+            delete[] p;
+            p = newData;
+            n = other.n;
+            c = other.c;
+        }
+        return *this;
+    }
+
+    Vector& operator=(Vector&& other) noexcept
+    {
+        if (this != &other) {
+            delete[] p;
+            p = other.p;
+            n = other.n;
+            c = other.c;
+            other.p = nullptr;
+            other.n = 0;
+            other.c = 0;
+        }
+        return *this;
+    }
+
+    bool empty() const
+    {
+        return !n;
+    }
+
+    size_t size() const
+    {
+        return n;
+    }
+
+    size_t capacity() const
+    {
+        return c;
+    }
+
+    T& operator[](size_t i)
+    {
+        if (i >= n)
+            __builtin_trap();
+        return p[i];
+    }
+
+    const T& operator[](size_t i) const
+    {
+        if (i >= n)
+            __builtin_trap();
+        return p[i];
+    }
+
+    iterator begin()
+    {
+        return p;
+    }
+
+    iterator end()
+    {
+        return p + n;
+    }
+
+    const_iterator cbegin() const
+    {
+        return p;
+    }
+
+    const_iterator cend() const
+    {
+        return p + n;
+    }
+
+    T& front()
+    {
+        if (!n)
+            __builtin_trap();
+        return p[0];
+    }
+
+    const T& front() const
+    {
+        if (!n)
+            __builtin_trap();
+        return p[0];
+    }
+
+    T& back()
+    {
+        if (!n)
+            __builtin_trap();
+        return p[n - 1];
+    }
+
+    const T& back() const
+    {
+        if (!n)
+            __builtin_trap();
+        return p[n - 1];
+    }
+
+    void clear()
+    {
+        for (size_t i = 0; i < n; ++i)
+            p[i].~T();
+        n = 0;
+    }
+
+    void reserve(size_t c2)
+    {
+        if (c2 <= c)
+            return;
+        T* newP = new T[c2];
+        for (size_t i = 0; i < n; ++i)
+            newP[i] = std::move(p[i]);
+        delete[] p;
+        p = newP;
+        c = c2;
+    }
+
+    void push_back(const T& e)
+    {
+        if (n == c) {
+            size_t c2 = c + 1;
+            c2 += c2 >> 1;
+            reserve(c2);
+        }
+        new (&p[n]) T(e);
+        ++n;
+    }
+
+    void push_back(T&& e)
+    {
+        if (n == c) {
+            size_t c2 = c + 1;
+            c2 += c2 >> 1;
+            reserve(c2);
+        }
+        new (&p[n]) T(std::forward<T>(e));
+        ++n;
+    }
+
+    template<typename... Args>
+    void emplace_back(Args&&... args)
+    {
+        if (n == c) {
+            size_t c2 = c + 1;
+            c2 += c2 >> 1;
+            reserve(c2);
+        }
+        new (&p[n]) T(std::forward<Args>(args)...);
+        ++n;
+    }
+
+    void pop_back()
+    {
+        if (n > 0) {
+            --n;
+            p[n].~T();
+        }
+    }
+
+    void resize(size_t n2)
+    {
+        if (n2 > n) {
+            reserve(n2);
+            for (size_t i = n; i < n2; ++i)
+                new (&p[i]) T();
+        } else if (n2 < n) {
+            for (size_t i = n2; i < n; ++i)
+                p[i].~T();
+        }
+        n = n2;
+    }
+
+    void swap(Vector& other) noexcept
+    {
+        std::swap(n, other.n);
+        std::swap(c, other.c);
+        std::swap(p, other.p);
+    }
+};
+
+#endif // COSMOPOLITAN_CTL_OPTIONAL_H_