Aws::String StringUtils::URLDecode()

in src/aws-cpp-sdk-core/source/utils/StringUtils.cpp [230:303]

• 70 lines of code
• 18 McCabe index (conditional complexity)

Aws::String StringUtils::URLDecode(const char* safe)
{
    Aws::String unescaped;

    for (; *safe; safe++)
    {
        switch(*safe)
        {
            case '%':
            {
                int hex = 0;
                auto ch = *++safe;
                if (ch >= '0' && ch <= '9')
                {
                    hex = (ch - '0') * 16;
                }
                else if (ch >= 'A' && ch <= 'F')
                {
                    hex = (ch - 'A' + 10) * 16;
                }
                else if (ch >= 'a' && ch <= 'f')
                {
                    hex = (ch - 'a' + 10) * 16;
                }
                else
                {
                    unescaped.push_back('%');
                    if (ch == 0)
                    {
                        return unescaped;
                    }
                    unescaped.push_back(ch);
                    break;
                }

                ch = *++safe;
                if (ch >= '0' && ch <= '9')
                {
                    hex += (ch - '0');
                }
                else if (ch >= 'A' && ch <= 'F')
                {
                    hex += (ch - 'A' + 10);
                }
                else if (ch >= 'a' && ch <= 'f')
                {
                    hex += (ch - 'a' + 10);
                }
                else
                {
                    unescaped.push_back('%');
                    unescaped.push_back(*(safe - 1));
                    if (ch == 0)
                    {
                        return unescaped;
                    }
                    unescaped.push_back(ch);
                    break;
                }

                unescaped.push_back(char(hex));
                break;
            }
            case '+':
                unescaped.push_back(' ');
                break;
            default:
                unescaped.push_back(*safe);
                break;
        }
    }

    return unescaped;
}