| /* |
| * Copyright (c) 2021, The OpenThread Authors. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. 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. |
| * 3. Neither the name of the copyright holder 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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 |
| * This file includes definitions for `Heap::String` (a heap allocated string). |
| */ |
| |
| #ifndef HEAP_STRING_HPP_ |
| #define HEAP_STRING_HPP_ |
| |
| #include "openthread-core-config.h" |
| |
| #include "common/equatable.hpp" |
| #include "common/error.hpp" |
| #include "common/heap.hpp" |
| |
| namespace ot { |
| namespace Heap { |
| |
| /** |
| * This class represents a heap allocated string. |
| * |
| * The buffer to store the string is allocated from heap and is manged by the `Heap::String` class itself, e.g., it may |
| * be reused and/or freed and reallocated when the string is set. The `Heap::String` destructor will always free the |
| * allocated buffer. |
| * |
| */ |
| class String : public Unequatable<String> |
| { |
| public: |
| /** |
| * This constructor initializes the `String` as null (or empty). |
| * |
| */ |
| String(void) |
| : mStringBuffer(nullptr) |
| { |
| } |
| |
| /** |
| * This is the move constructor for `String`. |
| * |
| * `String` is non-copyable (copy constructor is deleted) but move constructor is provided to allow it to to be |
| * used as return type (return by value) from functions/methods (which will then use move semantics). |
| * |
| */ |
| String(String &&aString) |
| : mStringBuffer(aString.mStringBuffer) |
| { |
| aString.mStringBuffer = nullptr; |
| } |
| |
| /** |
| * This is the destructor for `HealString` object |
| * |
| */ |
| ~String(void) { Free(); } |
| |
| /** |
| * This method indicates whether or not the `String` is null (i.e., it was never successfully set or it was |
| * freed). |
| * |
| * @retval TRUE The `String` is null. |
| * @retval FALSE The `String` is not null. |
| * |
| */ |
| bool IsNull(void) const { return (mStringBuffer == nullptr); } |
| |
| /** |
| * This method returns the `String` as a C string. |
| * |
| * @returns A pointer to C string buffer or `nullptr` if the `String` is null (never set or freed). |
| * |
| */ |
| const char *AsCString(void) const { return mStringBuffer; } |
| |
| /** |
| * This method sets the string from a given C string. |
| * |
| * @param[in] aCString A pointer to c string buffer. Can be `nullptr` which then frees the `String`. |
| * |
| * @retval kErrorNone Successfully set the string. |
| * @retval kErrorNoBufs Failed to allocate buffer for string. |
| * |
| */ |
| Error Set(const char *aCString); |
| |
| /** |
| * This method sets the string from another `String`. |
| * |
| * @param[in] aString The other `String` to set from. |
| * |
| * @retval kErrorNone Successfully set the string. |
| * @retval kErrorNoBufs Failed to allocate buffer for string. |
| * |
| */ |
| Error Set(const String &aString) { return Set(aString.AsCString()); } |
| |
| /** |
| * This method sets the string from another `String`. |
| * |
| * @param[in] aString The other `String` to set from (rvalue reference using move semantics). |
| * |
| * @retval kErrorNone Successfully set the string. |
| * @retval kErrorNoBufs Failed to allocate buffer for string. |
| * |
| */ |
| Error Set(String &&aString); |
| |
| /** |
| * This method frees any buffer allocated by the `String`. |
| * |
| * The `String` destructor will automatically call `Free()`. This method allows caller to free buffer |
| * explicitly. |
| * |
| */ |
| void Free(void); |
| |
| /** |
| * This method overloads operator `==` to evaluate whether or not the `String` is equal to a given C string. |
| * |
| * @param[in] aCString A C string to compare with. Can be `nullptr` which then checks if `String` is null. |
| * |
| * @retval TRUE If the two strings are equal. |
| * @retval FALSE If the two strings are not equal. |
| * |
| */ |
| bool operator==(const char *aCString) const; |
| |
| /** |
| * This method overloads operator `!=` to evaluate whether or not the `String` is unequal to a given C string. |
| * |
| * @param[in] aCString A C string to compare with. Can be `nullptr` which then checks if `String` is not null. |
| * |
| * @retval TRUE If the two strings are not equal. |
| * @retval FALSE If the two strings are equal. |
| * |
| */ |
| bool operator!=(const char *aCString) const { return !(*this == aCString); } |
| |
| /** |
| * This method overloads operator `==` to evaluate whether or not two `String` are equal. |
| * |
| * @param[in] aString The other string to compare with. |
| * |
| * @retval TRUE If the two strings are equal. |
| * @retval FALSE If the two strings are not equal. |
| * |
| */ |
| bool operator==(const String &aString) const { return (*this == aString.AsCString()); } |
| |
| String(const String &) = delete; |
| String &operator=(const String &) = delete; |
| |
| private: |
| char *mStringBuffer; |
| }; |
| |
| } // namespace Heap |
| } // namespace ot |
| |
| #endif // HEAP_STRING_HPP_ |