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@xylcbd xylcbd/cpp_web_tools.cpp
Last active Mar 8, 2017

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static const std::string base64_chars =
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+/";
static inline bool is_base64(unsigned char c) {
return (isalnum(c) || (c == '+') || (c == '/'));
}
std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {
std::string ret;
int i = 0;
int j = 0;
unsigned char char_array_3[3];
unsigned char char_array_4[4];
while (in_len--) {
char_array_3[i++] = *(bytes_to_encode++);
if (i == 3) {
char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
char_array_4[3] = char_array_3[2] & 0x3f;
for(i = 0; (i <4) ; i++)
ret += base64_chars[char_array_4[i]];
i = 0;
}
}
if (i)
{
for(j = i; j < 3; j++)
char_array_3[j] = '\0';
char_array_4[0] = ( char_array_3[0] & 0xfc) >> 2;
char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
char_array_4[3] = char_array_3[2] & 0x3f;
for (j = 0; (j < i + 1); j++)
ret += base64_chars[char_array_4[j]];
while((i++ < 3))
ret += '=';
}
return ret;
}
std::string base64_decode(std::string const& encoded_string) {
int in_len = encoded_string.size();
int i = 0;
int j = 0;
int in_ = 0;
unsigned char char_array_4[4], char_array_3[3];
std::string ret;
while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
char_array_4[i++] = encoded_string[in_]; in_++;
if (i ==4) {
for (i = 0; i <4; i++)
char_array_4[i] = base64_chars.find(char_array_4[i]);
char_array_3[0] = ( char_array_4[0] << 2 ) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (i = 0; (i < 3); i++)
ret += char_array_3[i];
i = 0;
}
}
if (i) {
for (j = i; j <4; j++)
char_array_4[j] = 0;
for (j = 0; j <4; j++)
char_array_4[j] = base64_chars.find(char_array_4[j]);
char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
for (j = 0; (j < i - 1); j++) ret += char_array_3[j];
}
return ret;
}
std::string charToHex(unsigned char c) {
short i = c;
std::stringstream s;
s << "%" << std::setw(2) << std::setfill('0') << std::hex << i;
return s.str();
}
unsigned char hexToChar(const std::string &str) {
short c = 0;
if(!str.empty()) {
std::istringstream in(str);
in >> std::hex >> c;
if(in.fail()) {
throw std::runtime_error("stream decode failure");
}
}
return static_cast<unsigned char>(c);
}
std::string urlEncode(const std::string &toEncode) {
std::ostringstream out;
for(std::string::size_type i=0; i < toEncode.length(); ++i) {
short t = toEncode.at(i);
if(
t == 45 || // hyphen
(t >= 48 && t <= 57) || // 0-9
(t >= 65 && t <= 90) || // A-Z
t == 95 || // underscore
(t >= 97 && t <= 122) || // a-z
t == 126 // tilde
) {
out << toEncode.at(i);
} else {
out << charToHex(toEncode.at(i));
}
}
return out.str();
}
std::string urlDecode(const std::string &toDecode) {
std::ostringstream out;
for(std::string::size_type i=0; i < toDecode.length(); ++i) {
if(toDecode.at(i) == '%') {
std::string str(toDecode.substr(i+1, 2));
out << hexToChar(str);
i += 2;
} else {
out << toDecode.at(i);
}
}
return out.str();
}
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