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+/**
+ * Copyright (c) 2017, Timothy Stack
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * * Neither the name of Timothy Stack nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * @file big_array.hh
+ */
+
+#ifndef lnav_big_array_hh
+#define lnav_big_array_hh
+
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include "base/math_util.hh"
+
+template<typename T>
+struct big_array {
+    static const size_t DEFAULT_INCREMENT = 100 * 1000;
+
+    big_array()
+        : ba_ptr(nullptr), ba_size(0), ba_capacity(0){
+
+                                       };
+
+    bool reserve(size_t size)
+    {
+        if (size < this->ba_capacity) {
+            return false;
+        }
+
+        if (this->ba_ptr) {
+            munmap(this->ba_ptr,
+                   roundup_size(this->ba_capacity * sizeof(T), getpagesize()));
+        }
+
+        this->ba_capacity = size + DEFAULT_INCREMENT;
+        void* result
+            = mmap(nullptr,
+                   roundup_size(this->ba_capacity * sizeof(T), getpagesize()),
+                   PROT_READ | PROT_WRITE,
+                   MAP_ANONYMOUS | MAP_PRIVATE,
+                   -1,
+                   0);
+
+        ensure(result != MAP_FAILED);
+
+        this->ba_ptr = (T*) result;
+
+        return true;
+    };
+
+    void clear()
+    {
+        this->ba_size = 0;
+    };
+
+    size_t size() const
+    {
+        return this->ba_size;
+    };
+
+    void shrink_to(size_t new_size)
+    {
+        require(new_size <= this->ba_size);
+
+        this->ba_size = new_size;
+    }
+
+    bool empty() const
+    {
+        return this->ba_size == 0;
+    };
+
+    void push_back(const T& val)
+    {
+        this->ba_ptr[this->ba_size] = val;
+        this->ba_size += 1;
+    };
+
+    T& operator[](size_t index)
+    {
+        return this->ba_ptr[index];
+    };
+
+    const T& operator[](size_t index) const
+    {
+        return this->ba_ptr[index];
+    };
+
+    T& back()
+    {
+        return this->ba_ptr[this->ba_size - 1];
+    }
+
+    typedef T* iterator;
+
+    iterator begin()
+    {
+        return this->ba_ptr;
+    };
+
+    iterator end()
+    {
+        return this->ba_ptr + this->ba_size;
+    };
+
+    T* ba_ptr;
+    size_t ba_size;
+    size_t ba_capacity;
+};
+
+#endif