www.pudn.com > MailSoftware.rar > base64.cpp

// base64.cpp - written and placed in the public domain by Wei Dai 
#include "stdafx.h" 
#include  
 
#include "base64.h" 
 
static const int MAX_LINE_LENGTH = 72; 
 
static const unsigned char vec[] = 
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 
 
static const unsigned char padding = '='; 
 
Base64Encoder::Base64Encoder(ostream& str, int lb) : 
	ostr(str) 
{ 
	line_breaks = lb; 
	inBufSize=0; 
	lineLength=0; 
} 
 
void Base64Encoder::LineBreak() 
{ 
	ostr << '\n'; 
	lineLength=0; 
} 
 
void Base64Encoder::EncodeQuantum() 
{ 
	unsigned char out; 
 
	out=(unsigned char)((inBuf[0] & 0xFC) >> 2); 
	ostr << vec[out]; 
 
	out=(unsigned char)(((inBuf[0] & 0x03) << 4) | (inBuf[1] >> 4)); 
	ostr << vec[out]; 
 
	out=(unsigned char)(((inBuf[1] & 0x0F) << 2) | (inBuf[2] >> 6)); 
	ostr << (inBufSize > 1 ? vec[out] : padding); 
 
	out=(unsigned char)(inBuf[2] & 0x3F); 
	ostr << (inBufSize > 2 ? vec[out] : padding); 
 
	inBufSize=0; 
	lineLength+=4; 
 
	if (line_breaks && (lineLength>=MAX_LINE_LENGTH)) 
		LineBreak(); 
} 
 
void Base64Encoder::Put(unsigned char inByte) 
 { 
	 inBuf[inBufSize++]=inByte; 
	 if (inBufSize==3) 
		EncodeQuantum(); 
 } 
 
void Base64Encoder::Put(const unsigned char* inString, unsigned int len) 
{ 
	while (len--) 
		Base64Encoder::Put(*inString++); 
} 
 
void Base64Encoder::InputFinished() 
{ 
	if (inBufSize) 
	{ 
		for (int i=inBufSize;i<3;i++) 
			inBuf[i]=0; 
 
		EncodeQuantum(); 
	 } 
 
	if (lineLength) // force a line break unless the current line is empty 
		LineBreak(); 
} 
 
Base64Decoder::Base64Decoder(ostream& str) : 
	ostr(str) 
{ 
	inBufSize=0; 
} 
 
void Base64Decoder::DecodeQuantum() 
{ 
	unsigned char out; 
 
	out = (unsigned char)((inBuf[0] << 2) | (inBuf[1] >> 4)); 
	ostr << out; 
 
	out = (unsigned char)((inBuf[1] << 4) | (inBuf[2] >> 2)); 
	if (inBufSize > 2) ostr << out; 
 
	out = (unsigned char)((inBuf[2] << 6) | inBuf[3]); 
	if (inBufSize > 3) ostr << out; 
 
	inBufSize=0; 
} 
 
int Base64Decoder::ConvToNumber(unsigned char inByte) 
{ 
	if (inByte >= 'A' && inByte <= 'Z') 
		return (inByte - 'A'); 
 
	if (inByte >= 'a' && inByte <= 'z') 
		return (inByte - 'a' + 26); 
 
	if (inByte >= '0' && inByte <= '9') 
		return (inByte - '0' + 52); 
 
	if (inByte == '+') 
		return (62); 
 
	if (inByte == '/') 
		return (63); 
 
	return (-1); 
} 
 
void Base64Decoder::Put(unsigned char inByte) 
{ 
	int i=ConvToNumber(inByte); 
	if (i >= 0) 
		inBuf[inBufSize++]=(unsigned char) i; 
	if (inBufSize==4) 
		DecodeQuantum(); 
} 
 
void Base64Decoder::Put(const unsigned char* inString, unsigned int len) 
{ 
 
	while (len--) 
		Base64Decoder::Put(*inString++); 
} 
 
void Base64Decoder::InputFinished() 
{ 
	if (inBufSize) 
	{ 
		for (int i=inBufSize;i<4;i++) 
			inBuf[i]=0; 
 
		DecodeQuantum(); 
	} 
}