thank you for your advice. I have search that file
/**
StreamString.h
Copyright (c) 2020 D. Gauchard. All rights reserved.
This file is part of the esp8266 core for Arduino environment.
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 __STREAMSTRING_H
#define __STREAMSTRING_H
#include <limits>
#include "WString.h"
///////////////////////////////////////////////////////////////
// S2Stream points to a String and makes it a Stream
// (it is also the helper for StreamString)
class S2Stream: public Stream
{
public:
S2Stream(String& string, int peekPointer = -1):
string(&string), peekPointer(peekPointer)
{
}
S2Stream(String* string, int peekPointer = -1):
string(string), peekPointer(peekPointer)
{
}
virtual int available() override
{
return string->length();
}
virtual int availableForWrite() override
{
return std::numeric_limits<int16_t>::max();
}
virtual int read() override
{
if (peekPointer < 0)
{
// consume chars
if (string->length())
{
char c = string->charAt(0);
string->remove(0, 1);
return c;
}
}
else if (peekPointer < (int)string->length())
{
// return pointed and move pointer
return string->charAt(peekPointer++);
}
// everything is read
return -1;
}
virtual size_t write(uint8_t data) override
{
return string->concat((char)data);
}
virtual int read(uint8_t* buffer, size_t len) override
{
if (peekPointer < 0)
{
// string will be consumed
size_t l = std::min(len, (size_t)string->length());
memcpy(buffer, string->c_str(), l);
string->remove(0, l);
return l;
}
if (peekPointer >= (int)string->length())
{
return 0;
}
// only the pointer is moved
size_t l = std::min(len, (size_t)(string->length() - peekPointer));
memcpy(buffer, string->c_str() + peekPointer, l);
peekPointer += l;
return l;
}
virtual size_t write(const uint8_t* buffer, size_t len) override
{
return string->concat((const char*)buffer, len) ? len : 0;
}
virtual int peek() override
{
if (peekPointer < 0)
{
if (string->length())
{
return string->charAt(0);
}
}
else if (peekPointer < (int)string->length())
{
return string->charAt(peekPointer);
}
return -1;
}
virtual void flush() override
{
// nothing to do
}
virtual bool inputCanTimeout() override
{
return false;
}
virtual bool outputCanTimeout() override
{
return false;
}
//// Stream's peekBufferAPI
virtual bool hasPeekBufferAPI() const override
{
return true;
}
virtual size_t peekAvailable()
{
if (peekPointer < 0)
{
return string->length();
}
return string->length() - peekPointer;
}
virtual const char* peekBuffer() override
{
if (peekPointer < 0)
{
return string->c_str();
}
if (peekPointer < (int)string->length())
{
return string->c_str() + peekPointer;
}
return nullptr;
}
virtual void peekConsume(size_t consume) override
{
if (peekPointer < 0)
{
// string is really consumed
string->remove(0, consume);
}
else
{
// only the pointer is moved
peekPointer = std::min((size_t)string->length(), peekPointer + consume);
}
}
virtual ssize_t streamRemaining() override
{
return peekPointer < 0 ? string->length() : string->length() - peekPointer;
}
// calling setConsume() will consume bytes as the stream is read
// (enabled by default)
void setConsume()
{
peekPointer = -1;
}
// Reading this stream will mark the string as read without consuming
// (not enabled by default)
// Calling resetPointer() resets the read state and allows rereading.
void resetPointer(int pointer = 0)
{
peekPointer = pointer;
}
protected:
String* string;
int peekPointer; // -1:String is consumed / >=0:resettable pointer
};
// StreamString is a S2Stream holding the String
class StreamString: public String, public S2Stream
{
protected:
void resetpp()
{
if (peekPointer > 0)
{
peekPointer = 0;
}
}
public:
StreamString(StreamString&& bro): String(bro), S2Stream(this) { }
StreamString(const StreamString& bro): String(bro), S2Stream(this) { }
// duplicate String constructors and operator=:
StreamString(const char* text = nullptr): String(text), S2Stream(this) { }
StreamString(const String& string): String(string), S2Stream(this) { }
StreamString(const __FlashStringHelper *str): String(str), S2Stream(this) { }
StreamString(String&& string): String(string), S2Stream(this) { }
explicit StreamString(char c): String(c), S2Stream(this) { }
explicit StreamString(unsigned char c, unsigned char base = 10): String(c, base), S2Stream(this) { }
explicit StreamString(int i, unsigned char base = 10): String(i, base), S2Stream(this) { }
explicit StreamString(unsigned int i, unsigned char base = 10): String(i, base), S2Stream(this) { }
explicit StreamString(long l, unsigned char base = 10): String(l, base), S2Stream(this) { }
explicit StreamString(unsigned long l, unsigned char base = 10): String(l, base), S2Stream(this) { }
explicit StreamString(float f, unsigned char decimalPlaces = 2): String(f, decimalPlaces), S2Stream(this) { }
explicit StreamString(double d, unsigned char decimalPlaces = 2): String(d, decimalPlaces), S2Stream(this) { }
StreamString& operator= (const StreamString& rhs)
{
String::operator=(rhs);
resetpp();
return *this;
}
StreamString& operator= (const String& rhs)
{
String::operator=(rhs);
resetpp();
return *this;
}
StreamString& operator= (const char* cstr)
{
String::operator=(cstr);
resetpp();
return *this;
}
StreamString& operator= (const __FlashStringHelper* str)
{
String::operator=(str);
resetpp();
return *this;
}
StreamString& operator= (String&& rval)
{
String::operator=(rval);
resetpp();
return *this;
}
};
#endif // __STREAMSTRING_H
and it do include this. what should i do then?