WString.h

/*
 WString.h - String library for Wiring & Arduino
 ...mostly rewritten by Paul Stoffregen...
 Copyright (c) 2009-10 Hernando Barragan.  All right reserved.
 Copyright 2011, Paul Stoffregen, paul@pjrc.com

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef String_class_h
#define String_class_h
#ifdef __cplusplus

#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <pgmspace.h>

// An inherited class for holding the result of a concatenation.  These
// result objects are assumed to be writable by subsequent concatenations.
class StringSumHelper;

// an abstract class used as a means to proide a unique pointer type
// but really has no body
class __FlashStringHelper;
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))

// The string class
class String
{
    // use a function pointer to allow for "if (s)" without the
    // complications of an operator bool(). for more information, see:
    // http://www.artima.com/cppsource/safebool.html
    typedef void (String::*StringIfHelperType)() const;
    void StringIfHelper() const
    {
    }

public:
    // constructors
    // creates a copy of the initial value.
    // if the initial value is null or invalid, or if memory allocation
    // fails, the string will be marked as invalid (i.e. "if (s)" will
    // be false).
    String(const char *cstr = "");
    String(const String &str);
    String(const __FlashStringHelper *str) : String(reinterpret_cast<const char *>(str)) {};
#ifdef __GXX_EXPERIMENTAL_CXX0X__
    String(String &&rval);
    String(StringSumHelper &&rval);
#endif
    explicit String(char c);
    explicit String(unsigned char, unsigned char base = 10);
    explicit String(int, unsigned char base = 10);
    explicit String(unsigned int, unsigned char base = 10);
    explicit String(long, unsigned char base = 10);
    explicit String(unsigned long, unsigned char base = 10);
    explicit String(float, unsigned char decimalPlaces = 2);
    explicit String(double, unsigned char decimalPlaces = 2);
    ~String(void);

    // memory management
    // return true on success, false on failure (in which case, the string
    // is left unchanged).  reserve(0), if successful, will validate an
    // invalid string (i.e., "if (s)" will be true afterwards)
    unsigned char reserve(unsigned int size);
    inline unsigned int length(void) const
    {
        if(buffer) {
            return len;
        } else {
            return 0;
        }
    }

    // creates a copy of the assigned value.  if the value is null or
    // invalid, or if the memory allocation fails, the string will be
    // marked as invalid ("if (s)" will be false).
    String & operator =(const String &rhs);
    String & operator =(const char *cstr);
    String & operator = (const __FlashStringHelper *str);
#ifdef __GXX_EXPERIMENTAL_CXX0X__
    String & operator =(String &&rval);
    String & operator =(StringSumHelper &&rval);
#endif

    // concatenate (works w/ built-in types)

    // returns true on success, false on failure (in which case, the string
    // is left unchanged).  if the argument is null or invalid, the
    // concatenation is considered unsucessful.
    unsigned char concat(const String &str);
    unsigned char concat(const char *cstr);
    unsigned char concat(char c);
    unsigned char concat(unsigned char c);
    unsigned char concat(int num);
    unsigned char concat(unsigned int num);
    unsigned char concat(long num);
    unsigned char concat(unsigned long num);
    unsigned char concat(float num);
    unsigned char concat(double num);
    unsigned char concat(const __FlashStringHelper * str);

    // if there's not enough memory for the concatenated value, the string
    // will be left unchanged (but this isn't signalled in any way)
    String & operator +=(const String &rhs)
    {
        concat(rhs);
        return (*this);
    }
    String & operator +=(const char *cstr)
    {
        concat(cstr);
        return (*this);
    }
    String & operator +=(char c)
    {
        concat(c);
        return (*this);
    }
    String & operator +=(unsigned char num)
    {
        concat(num);
        return (*this);
    }
    String & operator +=(int num)
    {
        concat(num);
        return (*this);
    }
    String & operator +=(unsigned int num)
    {
        concat(num);
        return (*this);
    }
    String & operator +=(long num)
    {
        concat(num);
        return (*this);
    }
    String & operator +=(unsigned long num)
    {
        concat(num);
        return (*this);
    }
    String & operator +=(float num)
    {
        concat(num);
        return (*this);
    }
    String & operator +=(double num)
    {
        concat(num);
        return (*this);
    }
    String & operator += (const __FlashStringHelper *str)
    {
        concat(str);
        return (*this);
    }

    friend StringSumHelper & operator +(const StringSumHelper &lhs, const String &rhs);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, const char *cstr);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, char c);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, unsigned char num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, int num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, unsigned int num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, long num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, unsigned long num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, float num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, double num);
    friend StringSumHelper & operator +(const StringSumHelper &lhs, const __FlashStringHelper *rhs);

    // comparison (only works w/ Strings and "strings")
    operator StringIfHelperType() const
    {
        return buffer ? &String::StringIfHelper : 0;
    }
    int compareTo(const String &s) const;
    unsigned char equals(const String &s) const;
    unsigned char equals(const char *cstr) const;
    unsigned char operator ==(const String &rhs) const
    {
        return equals(rhs);
    }
    unsigned char operator ==(const char *cstr) const
    {
        return equals(cstr);
    }
    unsigned char operator !=(const String &rhs) const
    {
        return !equals(rhs);
    }
    unsigned char operator !=(const char *cstr) const
    {
        return !equals(cstr);
    }
    unsigned char operator <(const String &rhs) const;
    unsigned char operator >(const String &rhs) const;
    unsigned char operator <=(const String &rhs) const;
    unsigned char operator >=(const String &rhs) const;
    unsigned char equalsIgnoreCase(const String &s) const;
    unsigned char startsWith(const String &prefix) const;
    unsigned char startsWith(const String &prefix, unsigned int offset) const;
    unsigned char endsWith(const String &suffix) const;

    // character acccess
    char charAt(unsigned int index) const;
    void setCharAt(unsigned int index, char c);
    char operator [](unsigned int index) const;
    char& operator [](unsigned int index);
    void getBytes(unsigned char *buf, unsigned int bufsize, unsigned int index = 0) const;
    void toCharArray(char *buf, unsigned int bufsize, unsigned int index = 0) const
    {
        getBytes((unsigned char *) buf, bufsize, index);
    }
    const char * c_str() const
    {
        return buffer;
    }

    // search
    int indexOf(char ch) const;
    int indexOf(char ch, unsigned int fromIndex) const;
    int indexOf(const String &str) const;
    int indexOf(const String &str, unsigned int fromIndex) const;
    int lastIndexOf(char ch) const;
    int lastIndexOf(char ch, unsigned int fromIndex) const;
    int lastIndexOf(const String &str) const;
    int lastIndexOf(const String &str, unsigned int fromIndex) const;
    String substring(unsigned int beginIndex) const
    {
        return substring(beginIndex, len);
    }
    ;
    String substring(unsigned int beginIndex, unsigned int endIndex) const;

    // modification
    void replace(char find, char replace);
    void replace(const String& find, const String& replace);
    void remove(unsigned int index);
    void remove(unsigned int index, unsigned int count);
    void toLowerCase(void);
    void toUpperCase(void);
    void trim(void);

    // parsing/conversion
    long toInt(void) const;
    float toFloat(void) const;

protected:
    char *buffer;	        // the actual char array
    unsigned int capacity;  // the array length minus one (for the '\0')
    unsigned int len;       // the String length (not counting the '\0')
protected:
    void init(void);
    void invalidate(void);
    unsigned char changeBuffer(unsigned int maxStrLen);
    unsigned char concat(const char *cstr, unsigned int length);

    // copy and move
    String & copy(const char *cstr, unsigned int length);
    String & copy(const __FlashStringHelper *pstr, unsigned int length);
#ifdef __GXX_EXPERIMENTAL_CXX0X__
    void move(String &rhs);
#endif
};

class StringSumHelper: public String
{
public:
    StringSumHelper(const String &s) :
        String(s)
    {
    }
    StringSumHelper(const char *p) :
        String(p)
    {
    }
    StringSumHelper(char c) :
        String(c)
    {
    }
    StringSumHelper(unsigned char num) :
        String(num)
    {
    }
    StringSumHelper(int num) :
        String(num)
    {
    }
    StringSumHelper(unsigned int num) :
        String(num)
    {
    }
    StringSumHelper(long num) :
        String(num)
    {
    }
    StringSumHelper(unsigned long num) :
        String(num)
    {
    }
    StringSumHelper(float num) :
        String(num)
    {
    }
    StringSumHelper(double num) :
        String(num)
    {
    }
};

#endif  // __cplusplus
#endif  // String_class_h