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px4-firmware/NxWidgets/libnxwidgets/include/cnxstring.hxx

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/****************************************************************************
* include/cnxtring.hxx
* NxWidgets/libnxwidgets/
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX, NxWidgets, nor the names of its contributors
* me 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 OWNER 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.
*
****************************************************************************
*
* Portions of this package derive from Woopsi (http://woopsi.org/) and
* portions are original efforts. It is difficult to determine at this
* point what parts are original efforts and which parts derive from Woopsi.
* However, in any event, the work of Antony Dzeryn will be acknowledged
* in most NxWidget files. Thanks Antony!
*
* Copyright (c) 2007-2011, Antony Dzeryn
* 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 names "Woopsi", "Simian Zombie" 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 Antony Dzeryn ``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 Antony Dzeryn 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.
*
****************************************************************************/
#ifndef __INCLUDE_CNXSTRING_HXX
#define __INCLUDE_CNXSTRING_HXX
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include "nxconfig.hxx"
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/****************************************************************************
* Implementation Classes
****************************************************************************/
#if defined(__cplusplus)
namespace NXWidgets
{
class CStringIterator;
/**
* Unicode string class. Uses 16-bt wide-character encoding. For optimal
* performance, use the CStringIterator class to iterate over a CNxString
* instance.
*
* Where possible, the string avoids allocating memory each time the
* string grows or shrinks. This means that the string may consume more
* memory than the number of chars would seem to dictate if the object
* previously contained a large string that has subsequently been truncated.
* It also means that increasing the length of such a string is a cheaper
* operation as memory does not need to allocated and copied.
*
* Additionally, the string increases its array size by m_growAmount every
* time it needs to allocate extra memory, potentially reducing the number
* of reallocs needed.
*
* The string is not null-terminated. Instead, it uses a m_stringLength
* member that stores the number of characters in the string. This saves a
* byte and makes calls to getLength() run in O(1) time instead of O(n).
*/
class CNxString
{
private:
friend class CStringIterator;
int m_stringLength; /**< Number of characters in the string */
int m_allocatedSize; /**< Number of bytes allocated for this string */
int m_growAmount; /**< Number of chars that the string grows by
whenever it needs to get larger */
protected:
FAR nxwidget_char_t *m_text; /**< Raw char array data */
/**
* Allocate memory for the string.
*
* @param chars Number of chars to allocate.
* @param preserve If true, the data in the existing memory will be
* preserved if new memory must be allocated
*/
void allocateMemory(int chars, bool preserve);
/**
* Check if we've got any string data stored or not.
*
* @return True if the string contains any data; false if no data has
* yet been supplied.
*/
inline bool hasData(void) const
{
return m_stringLength > 0;
}
/**
* Get the amount of allocated memory.
*
* @return The number of chars allocated in RAM.
*/
inline int getAllocatedSize(void) const
{
return m_allocatedSize;
}
/**
* Returns a pointer to the raw char array data.
*
* @return Pointer to the char array.
*/
inline FAR const nxwidget_char_t *getCharArray(void) const
{
return m_text;
}
/**
* Return a pointer to the specified character.
*
* @param index Index of the character to retrieve.
*/
FAR nxwidget_char_t *getCharPointer(const int index) const;
public:
/**
* Constructor to create an empty string object.
*/
CNxString();
/**
* Constructor to create a string from a C character array.
*
* @param text Pointer to a char array to use as the basis of the
* string.
*/
CNxString(FAR const char *text);
/**
* Constructor to create a string from a single character.
*
* @param letter Single character to use as the basis of the string.
*/
CNxString(const nxwidget_char_t letter);
/**
* Copy constructor.
* @param string CNxString object to create a copy of.
*/
CNxString(const CNxString &string);
/**
* Destructor.
*/
inline ~CNxString()
{
delete[] m_text;
m_text = (FAR nxwidget_char_t *)NULL;
};
/**
* Creates and returns a new CStringIterator object that will iterate
* over this string. The object must be manually deleted once it is
* no longer needed.
*
* @return A new CStringIterator object.
*/
CStringIterator *newStringIterator(void) const;
/**
* Copy the internal array to the supplied buffer. The buffer must be
* large enough to contain the full text in the string. The
* getByteCount() method can be used to obtain the length of the string.
* Unlike the CNxString class, the char array is null-terminated.
* The buffer must be (getByteCount() + 1) bytes long, in order to
* accommodate the terminator.
*
* @param buffer Buffer to copy the internal char array to.
*/
void copyToCharArray(FAR nxwidget_char_t *buffer) const;
/**
* Set the text in the string.
*
* @param text CNxString containing the new data for this string.
*/
void setText(const CNxString &text);
/**
* Set the text in the string.
*
* @param text Char array to use as the new data for this string.
*/
void setText(FAR const char *text);
/**
* Set the nxwidget_char_t text in the string.
*
* @param text Char array to use as the new data for this string.
*/
void setText(FAR const nxwidget_char_t *text, int nchars);
/**
* Set the 8-bit C-string text in the string.
*
* @param text Character to to use as the new data for this string.
*/
void setText(const nxwidget_char_t text);
/**
* Append text to the end of the string.
*
* @param text String to append.
*/
void append(const CNxString &text);
/**
* Insert text at the specified character index.
*
* @param text The text to insert.
* @param index The index at which to insert the text.
*/
void insert(const CNxString &text, const int index);
/**
* Remove all characters from the string from the start index onwards.
*
* @param startIndex Index to remove from.
*/
void remove(const int startIndex);
/**
* Remove specified number of characters from the string from the
* start index onwards.
*
* @param startIndex Index to remove from.
* @param count Number of characters to remove.
*/
void remove(const int startIndex, const int count);
/**
* Get the of number of letters (ie. the length) of the string.
*
* @return The length of the string.
*/
inline const int getLength(void) const
{
return m_stringLength;
};
/**
* Get the character at the specified index. This function is useful
* for finding the occasional character at an index, but for iterating
* over strings it is exceptionally slow. The newStringIterator()
* method should be used to retrieve an iterator object that can iterate
* over the string efficiently.
*
* @param index The index of the character to retrieve.
* @return The character at the specified index.
*/
const nxwidget_char_t getCharAt(int index) const;
/**
* Returns the first index of the specified letter within the string.
* Will return -1 if the letter is not found.
*
* @param letter Letter to find.
* @return The index of the letter.
*/
const int indexOf(nxwidget_char_t letter) const;
/**
* Returns the first index of the specified letter within the string.
* Will return -1 if the letter is not found. Scans through the string
* from "startIndex" until it has examined all subsequent letters.
* @param letter Letter to find.
*
* @param startIndex The index to start searching from.
* @return The index of the letter.
*/
const int indexOf(nxwidget_char_t letter, int startIndex) const;
/**
* Returns the first index of the specified letter within the string.
* Will return -1 if the letter is not found. Scans through the string
* from "startIndex" until it has examined all letters within the
* range "count".
*
* @param letter Letter to find.
* @param startIndex The index to start searching from.
* @param count The number of characters to examine.
* @return The index of the letter.
*/
const int indexOf(nxwidget_char_t letter, int startIndex, int count) const;
/**
* Returns the last index of the specified letter within the string.
* Will return -1 if the letter is not found.
*
* @param letter Letter to find.
* @return The index of the letter.
*/
const int lastIndexOf(nxwidget_char_t letter) const;
/**
* Returns the last index of the specified letter within the string.
* Will return -1 if the letter is not found. Scans through the string
* backwards from "startIndex" until it has examined all preceding
* letters within the string.
*
* @param letter Letter to find.
* @param startIndex The index to start searching from.
* @return The index of the letter.
*/
const int lastIndexOf(nxwidget_char_t letter, int startIndex) const;
/**
* Returns the last index of the specified letter within the string.
* Will return -1 if the letter is not found. Scans through the string
* backwards from "startIndex" until it has examined all letters within
* the range "count".
* @param letter Letter to find.
* @param startIndex The index to start searching from.
* @param count The number of characters to examine.
* @return The index of the letter.
*/
const int lastIndexOf(nxwidget_char_t letter, int startIndex, int count) const;
/**
* Get a substring from this string. It is the responsibility of the
* caller to delete the substring when it is no longer required.
*
* @param startIndex The starting point of the substring.
* @return A pointer to a new CNxString object containing the
* substring.
*/
CNxString *subString(int startIndex) const;
/**
* Get a substring from this string. It is the responsibility of the
* caller to delete the substring when it is no longer required.
*
* @param startIndex The starting point of the substring.
* @param length The length of the substring.
* @return A pointer to a new CNxString object containing the
* substring.
*/
CNxString *subString(int startIndex, int length) const;
/**
* Overloaded assignment operator. Copies the data within the argument
* string to this string.
*
* @param string The string to copy.
* @return This string.
*/
CNxString &operator=(const CNxString &string);
/**
* Overloaded assignment operator. Copies the data within the argument
* char array to this string.
*
* @param string The string to copy.
* @return This string.
*/
CNxString &operator=(const char *string);
/**
* Overloaded assignment operator. Copies the data from the argument
* char to this string.
*
* @param letter The char to copy.
* @return This string.
*/
CNxString& operator=(nxwidget_char_t letter);
/**
* Compares this string to the argument.
*
* @param string String to compare to.
* @return Zero if both strings are equal. A value greater than zero
* indicates that this string is greater than the argument string. A
* value less than zero indicates the opposite. Note that the return
* value indicates the *byte* that does not match, not the *character*.
*/
int compareTo(const CNxString &string) const;
};
}
#endif // __cplusplus
#endif // __INCLUDE_CNXSTRING_HXX
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