llstring.cpp

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#include "linden_common.h"

#include "llstring.h"
#include "llerror.h"

#if LL_WINDOWS
#define WIN32_LEAN_AND_MEAN
#include <winsock2.h>
#include <windows.h>
#include <winnls.h> // for WideCharToMultiByte
#endif

std::string ll_safe_string(const char* in)
{
        if(in) return std::string(in);
        return std::string();
}

U8 hex_as_nybble(char hex)
{
        if((hex >= '0') && (hex <= '9'))
        {
                return (U8)(hex - '0');
        }
        else if((hex >= 'a') && (hex <='f'))
        {
                return (U8)(10 + hex - 'a');
        }
        else if((hex >= 'A') && (hex <='F'))
        {
                return (U8)(10 + hex - 'A');
        }
        return 0; // uh - oh, not hex any more...
}


bool _read_file_into_string(std::string& str, const char* filename)
{
        llifstream ifs(filename, llifstream::binary);
        if (!ifs.is_open())
        {
                llinfos << "Unable to open file" << filename << llendl;
                return false;
        }

        std::ostringstream oss;

        oss << ifs.rdbuf();
        str = oss.str();
        ifs.close();
        return true;
}




// See http://www.unicode.org/Public/BETA/CVTUTF-1-2/ConvertUTF.c
// for the Unicode implementation - this doesn't match because it was written before finding
// it.


std::ostream& operator<<(std::ostream &s, const LLWString &wstr)
{
        std::string utf8_str = wstring_to_utf8str(wstr);
        s << utf8_str;
        return s;
}

std::string rawstr_to_utf8(const std::string& raw)
{
        LLWString wstr(utf8str_to_wstring(raw));
        return wstring_to_utf8str(wstr);
}

S32 wchar_to_utf8chars(llwchar in_char, char* outchars)
{
        U32 cur_char = (U32)in_char;
        char* base = outchars;
        if (cur_char < 0x80)
        {
                *outchars++ = (U8)cur_char;
        }
        else if (cur_char < 0x800)
        {
                *outchars++ = 0xC0 | (cur_char >> 6);
                *outchars++ = 0x80 | (cur_char & 0x3F);
        }
        else if (cur_char < 0x10000)
        {
                *outchars++ = 0xE0 | (cur_char >> 12);
                *outchars++ = 0x80 | ((cur_char >> 6) & 0x3F);
                *outchars++ = 0x80 | (cur_char & 0x3F);
        }
        else if (cur_char < 0x200000)
        {
                *outchars++ = 0xF0 | (cur_char >> 18);
                *outchars++ = 0x80 | ((cur_char >> 12) & 0x3F);
                *outchars++ = 0x80 | ((cur_char >> 6) & 0x3F);
                *outchars++ = 0x80 | cur_char & 0x3F;
        }
        else if (cur_char < 0x4000000)
        {
                *outchars++ = 0xF8 | (cur_char >> 24);
                *outchars++ = 0x80 | ((cur_char >> 18) & 0x3F);
                *outchars++ = 0x80 | ((cur_char >> 12) & 0x3F);
                *outchars++ = 0x80 | ((cur_char >> 6) & 0x3F);
                *outchars++ = 0x80 | cur_char & 0x3F;
        }
        else if (cur_char < 0x80000000)
        {
                *outchars++ = 0xFC | (cur_char >> 30);
                *outchars++ = 0x80 | ((cur_char >> 24) & 0x3F);
                *outchars++ = 0x80 | ((cur_char >> 18) & 0x3F);
                *outchars++ = 0x80 | ((cur_char >> 12) & 0x3F);
                *outchars++ = 0x80 | ((cur_char >> 6) & 0x3F);
                *outchars++ = 0x80 | cur_char & 0x3F;
        }
        else
        {
                llwarns << "Invalid Unicode character " << cur_char << "!" << llendl;
                *outchars++ = LL_UNKNOWN_CHAR;
        }
        return outchars - base;
}       

S32 utf16chars_to_wchar(const U16* inchars, llwchar* outchar)
{
        const U16* base = inchars;
        U16 cur_char = *inchars++;
        llwchar char32 = cur_char;
        if ((cur_char >= 0xD800) && (cur_char <= 0xDFFF))
        {
                // Surrogates
                char32 = ((llwchar)(cur_char - 0xD800)) << 10;
                cur_char = *inchars++;
                char32 += (llwchar)(cur_char - 0xDC00) + 0x0010000UL;
        }
        else
        {
                char32 = (llwchar)cur_char;
        }
        *outchar = char32;
        return inchars - base;
}

S32 utf16chars_to_utf8chars(const U16* inchars, char* outchars, S32* nchars8p)
{
        // Get 32 bit char32
        llwchar char32;
        S32 nchars16 = utf16chars_to_wchar(inchars, &char32);
        // Convert to utf8
        S32 nchars8  = wchar_to_utf8chars(char32, outchars);
        if (nchars8p)
        {
                *nchars8p = nchars8;
        }
        return nchars16;
}

llutf16string wstring_to_utf16str(const LLWString &utf32str, S32 len)
{
        llutf16string out;

        S32 i = 0;
        while (i < len)
        {
                U32 cur_char = utf32str[i];
                if (cur_char > 0xFFFF)
                {
                        out += (0xD7C0 + (cur_char >> 10));
                        out += (0xDC00 | (cur_char & 0x3FF));
                }
                else
                {
                        out += cur_char;
                }
                i++;
        }
        return out;
}

llutf16string wstring_to_utf16str(const LLWString &utf32str)
{
        const S32 len = (S32)utf32str.length();
        return wstring_to_utf16str(utf32str, len);
}

llutf16string utf8str_to_utf16str ( const LLString& utf8str )
{
        LLWString wstr = utf8str_to_wstring ( utf8str );
        return wstring_to_utf16str ( wstr );
}


LLWString utf16str_to_wstring(const llutf16string &utf16str, S32 len)
{
        LLWString wout;
        if((len <= 0) || utf16str.empty()) return wout;

        S32 i = 0;
        // craziness to make gcc happy (llutf16string.c_str() is tweaked on linux):
        const U16* chars16 = &(*(utf16str.begin()));
        while (i < len)
        {
                llwchar cur_char;
                i += utf16chars_to_wchar(chars16+i, &cur_char);
                wout += cur_char;
        }
        return wout;
}

LLWString utf16str_to_wstring(const llutf16string &utf16str)
{
        const S32 len = (S32)utf16str.length();
        return utf16str_to_wstring(utf16str, len);
}

// Length in llwchar (UTF-32) of the first len units (16 bits) of the given UTF-16 string.
S32 utf16str_wstring_length(const llutf16string &utf16str, const S32 utf16_len)
{
        S32 surrogate_pairs = 0;
        // ... craziness to make gcc happy (llutf16string.c_str() is tweaked on linux):
        const U16 *const utf16_chars = &(*(utf16str.begin()));
        S32 i = 0;
        while (i < utf16_len)
        {
                const U16 c = utf16_chars[i++];
                if (c >= 0xD800 && c <= 0xDBFF)         // See http://en.wikipedia.org/wiki/UTF-16
                {   // Have first byte of a surrogate pair
                        if (i >= utf16_len)
                        {
                                break;
                        }
                        const U16 d = utf16_chars[i];
                        if (d >= 0xDC00 && d <= 0xDFFF)
                        {   // Have valid second byte of a surrogate pair
                                surrogate_pairs++;
                                i++;
                        }
                }
        }
        return utf16_len - surrogate_pairs;
}

// Length in utf16string (UTF-16) of wlen wchars beginning at woffset.
S32 wstring_utf16_length(const LLWString &wstr, const S32 woffset, const S32 wlen)
{
        const S32 end = llmin((S32)wstr.length(), woffset + wlen);
        if (end < woffset)
        {
                return 0;
        }
        else
        {
                S32 length = end - woffset;
                for (S32 i = woffset; i < end; i++)
                {
                        if (wstr[i] >= 0x10000)
                        {
                                length++;
                        }
                }
                return length;
        }
}

// Given a wstring and an offset in it, returns the length as wstring (i.e.,
// number of llwchars) of the longest substring that starts at the offset
// and whose equivalent utf-16 string does not exceeds the given utf16_length.
S32 wstring_wstring_length_from_utf16_length(const LLWString & wstr, const S32 woffset, const S32 utf16_length, BOOL *unaligned)
{
        const S32 end = wstr.length();
        BOOL u = FALSE;
        S32 n = woffset + utf16_length;
        S32 i = woffset;
        while (i < end)
        {
                if (wstr[i] >= 0x10000)
                {
                        --n;
                }
                if (i >= n)
                {
                        u = (i > n);
                        break;
                }
                i++;
        }
        if (unaligned)
        {
                *unaligned = u;
        }
        return i - woffset;
}

S32 wchar_utf8_length(const llwchar wc)
{
        if (wc < 0x80)
        {
                // This case will also catch negative values which are
                // technically invalid.
                return 1;
        }
        else if (wc < 0x800)
        {
                return 2;
        }
        else if (wc < 0x10000)
        {
                return 3;
        }
        else if (wc < 0x200000)
        {
                return 4;
        }
        else if (wc < 0x4000000)
        {
                return 5;
        }
        else
        {
                return 6;
        }
}


S32 wstring_utf8_length(const LLWString& wstr)
{
        S32 len = 0;
        for (S32 i = 0; i < (S32)wstr.length(); i++)
        {
                len += wchar_utf8_length(wstr[i]);
        }
        return len;
}


LLWString utf8str_to_wstring(const std::string& utf8str, S32 len)
{
        LLWString wout;

        S32 i = 0;
        while (i < len)
        {
                llwchar unichar;
                U8 cur_char = utf8str[i];

                if (cur_char < 0x80)
                {
                        // Ascii character, just add it
                        unichar = cur_char;
                }
                else
                {
                        S32 cont_bytes = 0;
                        if ((cur_char >> 5) == 0x6)                     // Two byte UTF8 -> 1 UTF32
                        {
                                unichar = (0x1F&cur_char);
                                cont_bytes = 1;
                        }
                        else if ((cur_char >> 4) == 0xe)        // Three byte UTF8 -> 1 UTF32
                        {
                                unichar = (0x0F&cur_char);
                                cont_bytes = 2;
                        }
                        else if ((cur_char >> 3) == 0x1e)       // Four byte UTF8 -> 1 UTF32
                        {
                                unichar = (0x07&cur_char);
                                cont_bytes = 3;
                        }
                        else if ((cur_char >> 2) == 0x3e)       // Five byte UTF8 -> 1 UTF32
                        {
                                unichar = (0x03&cur_char);
                                cont_bytes = 4;
                        }
                        else if ((cur_char >> 1) == 0x7e)       // Six byte UTF8 -> 1 UTF32
                        {
                                unichar = (0x01&cur_char);
                                cont_bytes = 5;
                        }
                        else
                        {
                                wout += LL_UNKNOWN_CHAR;
                                ++i;
                                continue;
                        }

                        // Check that this character doesn't go past the end of the string
                        S32 end = (len < (i + cont_bytes)) ? len : (i + cont_bytes);
                        do
                        {
                                ++i;

                                cur_char = utf8str[i];
                                if ( (cur_char >> 6) == 0x2 )
                                {
                                        unichar <<= 6;
                                        unichar += (0x3F&cur_char);
                                }
                                else
                                {
                                        // Malformed sequence - roll back to look at this as a new char
                                        unichar = LL_UNKNOWN_CHAR;
                                        --i;
                                        break;
                                }
                        } while(i < end);

                        // Handle overlong characters and NULL characters
                        if ( ((cont_bytes == 1) && (unichar < 0x80))
                                || ((cont_bytes == 2) && (unichar < 0x800))
                                || ((cont_bytes == 3) && (unichar < 0x10000))
                                || ((cont_bytes == 4) && (unichar < 0x200000))
                                || ((cont_bytes == 5) && (unichar < 0x4000000)) )
                        {
                                unichar = LL_UNKNOWN_CHAR;
                        }
                }

                wout += unichar;
                ++i;
        }
        return wout;
}

LLWString utf8str_to_wstring(const std::string& utf8str)
{
        const S32 len = (S32)utf8str.length();
        return utf8str_to_wstring(utf8str, len);
}

std::string wstring_to_utf8str(const LLWString& utf32str, S32 len)
{
        std::string out;

        S32 i = 0;
        while (i < len)
        {
                char tchars[8];         /* Flawfinder: ignore */
                S32 n = wchar_to_utf8chars(utf32str[i], tchars);
                tchars[n] = 0;
                out += tchars;
                i++;
        }
        return out;
}

std::string wstring_to_utf8str(const LLWString& utf32str)
{
        const S32 len = (S32)utf32str.length();
        return wstring_to_utf8str(utf32str, len);
}

std::string utf16str_to_utf8str(const llutf16string& utf16str)
{
        return wstring_to_utf8str(utf16str_to_wstring(utf16str));
}

std::string utf16str_to_utf8str(const llutf16string& utf16str, S32 len)
{
        return wstring_to_utf8str(utf16str_to_wstring(utf16str, len), len);
}


//LLWString wstring_truncate(const LLWString &wstr, const S32 max_len)
//{
//      return wstr.substr(0, llmin((S32)wstr.length(), max_len));
//}
//
//
//LLWString wstring_trim(const LLWString &wstr)
//{
//      LLWString outstr;
//      outstr = wstring_trimhead(wstr);
//      outstr = wstring_trimtail(outstr);
//      return outstr;
//}
//
//
//LLWString wstring_trimhead(const LLWString &wstr)
//{
//      if(wstr.empty())
//      {
//              return wstr;
//      }
//
//    S32 i = 0;
//      while((i < (S32)wstr.length()) && iswspace(wstr[i]))
//      {
//              i++;
//      }
//      return wstr.substr(i, wstr.length() - i);
//}
//
//
//LLWString wstring_trimtail(const LLWString &wstr)
//{                     
//      if(wstr.empty())
//      {
//              return wstr;
//      }
//
//      S32 len = (S32)wstr.length();
//
//      S32 i = len - 1;
//      while (i >= 0 && iswspace(wstr[i]))
//      {
//              i--;
//      }
//
//      if (i >= 0)
//      {
//              return wstr.substr(0, i + 1);
//      }
//      return wstr;
//}
//
//
//LLWString wstring_copyinto(const LLWString &dest, const LLWString &src, const S32 insert_offset)
//{
//      llassert( insert_offset <= (S32)dest.length() );
//
//      LLWString out_str = dest.substr(0, insert_offset);
//      out_str += src;
//      LLWString tail = dest.substr(insert_offset);
//      out_str += tail;
//
//      return out_str;
//}


//LLWString wstring_detabify(const LLWString &wstr, const S32 num_spaces)
//{
//      LLWString out_str;
//      // Replace tabs with spaces
//      for (S32 i = 0; i < (S32)wstr.length(); i++)
//      {
//              if (wstr[i] == '\t')
//              {
//                      for (S32 j = 0; j < num_spaces; j++)
//                              out_str += ' ';
//              }
//              else
//              {
//                      out_str += wstr[i];
//              }
//      }
//      return out_str;
//}


//LLWString wstring_makeASCII(const LLWString &wstr)
//{
//      // Replace non-ASCII chars with replace_char
//      LLWString out_str = wstr;
//      for (S32 i = 0; i < (S32)out_str.length(); i++)
//      {
//              if (out_str[i] > 0x7f)
//              {
//                      out_str[i] = LL_UNKNOWN_CHAR;
//              }
//      }
//      return out_str;
//}


//LLWString wstring_substChar(const LLWString &wstr, const llwchar target_char, const llwchar replace_char)
//{
//      // Replace all occurences of target_char with replace_char
//      LLWString out_str = wstr;
//      for (S32 i = 0; i < (S32)out_str.length(); i++)
//      {
//              if (out_str[i] == target_char)
//              {
//                      out_str[i] = replace_char;
//              }
//      }
//      return out_str;
//}
//
//
//LLWString wstring_tolower(const LLWString &wstr)
//{
//      LLWString out_str = wstr;
//      for (S32 i = 0; i < (S32)out_str.length(); i++)
//      {
//              out_str[i] = towlower(out_str[i]);
//      }
//      return out_str;
//}
//
//
//LLWString wstring_convert_to_lf(const LLWString &wstr)
//{
//      const llwchar CR = 13;
//      // Remove carriage returns from string with CRLF
//      LLWString out_str;
//
//      for (S32 i = 0; i < (S32)wstr.length(); i++)
//      {
//              if (wstr[i] != CR)
//              {
//                      out_str += wstr[i];
//              }
//      }
//      return out_str;
//}
//
//
//LLWString wstring_convert_to_crlf(const LLWString &wstr)
//{
//      const llwchar LF = 10;
//      const llwchar CR = 13;
//      // Remove carriage returns from string with CRLF
//      LLWString out_str;
//
//      for (S32 i = 0; i < (S32)wstr.length(); i++)
//      {
//              if (wstr[i] == LF)
//              {
//                      out_str += CR;
//              }
//              out_str += wstr[i];
//      }
//      return out_str;
//}


//S32   wstring_compare_insensitive(const LLWString &lhs, const LLWString &rhs)
//{
//
//      if (lhs == rhs)
//      {
//              return 0;
//      }
//
//      if (lhs.empty())
//      {
//              return rhs.empty() ? 0 : 1;
//      }
//
//      if (rhs.empty())
//      {
//              return -1;
//      }
//
//#ifdef LL_LINUX
//      // doesn't work because gcc 2.95 doesn't correctly implement c_str().  Sigh...
//      llerrs << "wstring_compare_insensitive doesn't work on Linux!" << llendl;
//      return 0;
//#else
//      LLWString lhs_lower = lhs;
//      LLWString::toLower(lhs_lower);
//      std::string lhs_lower = wstring_to_utf8str(lhs_lower);
//      LLWString rhs_lower = lhs;
//      LLWString::toLower(rhs_lower);
//      std::string rhs_lower = wstring_to_utf8str(rhs_lower);
//
//      return strcmp(lhs_lower.c_str(), rhs_lower.c_str());
//#endif
//}


std::string utf8str_trim(const std::string& utf8str)
{
        LLWString wstr = utf8str_to_wstring(utf8str);
        LLWString::trim(wstr);
        return wstring_to_utf8str(wstr);
}


std::string utf8str_tolower(const std::string& utf8str)
{
        LLWString out_str = utf8str_to_wstring(utf8str);
        LLWString::toLower(out_str);
        return wstring_to_utf8str(out_str);
}


S32 utf8str_compare_insensitive(const std::string& lhs, const std::string& rhs)
{
        LLWString wlhs = utf8str_to_wstring(lhs);
        LLWString wrhs = utf8str_to_wstring(rhs);
        return LLWString::compareInsensitive(wlhs.c_str(), wrhs.c_str());
}

std::string utf8str_truncate(const std::string& utf8str, const S32 max_len)
{
        if (0 == max_len)
        {
                return std::string();
        }
        if ((S32)utf8str.length() <= max_len)
        {
                return utf8str;
        }
        else
        {
                S32 cur_char = max_len;

                // If we're ASCII, we don't need to do anything
                if ((U8)utf8str[cur_char] > 0x7f)
                {
                        // If first two bits are (10), it's the tail end of a multibyte char.  We need to shift back
                        // to the first character
                        while (0x80 == (0xc0 & utf8str[cur_char]))
                        {
                                cur_char--;
                                // Keep moving forward until we hit the first char;
                                if (cur_char == 0)
                                {
                                        // Make sure we don't trash memory if we've got a bogus string.
                                        break;
                                }
                        }
                }
                // The byte index we're on is one we want to get rid of, so we only want to copy up to (cur_char-1) chars
                return utf8str.substr(0, cur_char);
        }
}

std::string utf8str_substChar(
        const std::string& utf8str,
        const llwchar target_char,
        const llwchar replace_char)
{
        LLWString wstr = utf8str_to_wstring(utf8str);
        LLWString::replaceChar(wstr, target_char, replace_char);
        //wstr = wstring_substChar(wstr, target_char, replace_char);
        return wstring_to_utf8str(wstr);
}

std::string utf8str_makeASCII(const std::string& utf8str)
{
        LLWString wstr = utf8str_to_wstring(utf8str);
        LLWString::_makeASCII(wstr);
        return wstring_to_utf8str(wstr);
}

std::string mbcsstring_makeASCII(const std::string& wstr)
{
        // Replace non-ASCII chars with replace_char
        std::string out_str = wstr;
        for (S32 i = 0; i < (S32)out_str.length(); i++)
        {
                if ((U8)out_str[i] > 0x7f)
                {
                        out_str[i] = LL_UNKNOWN_CHAR;
                }
        }
        return out_str;
}
std::string utf8str_removeCRLF(const std::string& utf8str)
{
        if (0 == utf8str.length())
        {
                return std::string();
        }
        const char CR = 13;

        std::string out;
        out.reserve(utf8str.length());
        const S32 len = (S32)utf8str.length();
        for( S32 i = 0; i < len; i++ )
        {
                if( utf8str[i] != CR )
                {
                        out.push_back(utf8str[i]);
                }
        }
        return out;
}

#if LL_WINDOWS
// documentation moved to header. Phoenix 2007-11-27
namespace snprintf_hack
{
        int snprintf(char *str, size_t size, const char *format, ...)
        {
                va_list args;
                va_start(args, format);

                int num_written = _vsnprintf(str, size, format, args); /* Flawfinder: ignore */
                va_end(args);
                
                str[size-1] = '\0'; // always null terminate
                return num_written;
        }
}

std::string ll_convert_wide_to_string(const wchar_t* in)
{
        std::string out;
        if(in)
        {
                int len_in = wcslen(in);
                int len_out = WideCharToMultiByte(
                        CP_ACP,
                        0,
                        in,
                        len_in,
                        NULL,
                        0,
                        0,
                        0);
                // We will need two more bytes for the double NULL ending
                // created in WideCharToMultiByte().
                char* pout = new char [len_out + 2];
                memset(pout, 0, len_out + 2);
                if(pout)
                {
                        WideCharToMultiByte(
                                CP_ACP,
                                0,
                                in,
                                len_in,
                                pout,
                                len_out,
                                0,
                                0);
                        out.assign(pout);
                        delete[] pout;
                }
        }
        return out;
}
#endif // LL_WINDOWS

S32     LLStringOps::collate(const llwchar* a, const llwchar* b)
{ 
        #if LL_WINDOWS
                // in Windows, wide string functions operator on 16-bit strings, 
                // not the proper 32 bit wide string
                return strcmp(wstring_to_utf8str(LLWString(a)).c_str(), wstring_to_utf8str(LLWString(b)).c_str());
        #else
                return wcscoll(a, b);
        #endif
}

namespace LLStringFn
{
        void replace_nonprintable(std::basic_string<char>& string, char replacement)
        {
                const char MIN = 0x20;
                std::basic_string<char>::size_type len = string.size();
                for(std::basic_string<char>::size_type ii = 0; ii < len; ++ii)
                {
                        if(string[ii] < MIN)
                        {
                                string[ii] = replacement;
                        }
                }
        }

        void replace_nonprintable(
                std::basic_string<llwchar>& string,
                llwchar replacement)
        {
                const llwchar MIN = 0x20;
                const llwchar MAX = 0x7f;
                std::basic_string<llwchar>::size_type len = string.size();
                for(std::basic_string<llwchar>::size_type ii = 0; ii < len; ++ii)
                {
                        if((string[ii] < MIN) || (string[ii] > MAX))
                        {
                                string[ii] = replacement;
                        }
                }
        }

        void replace_nonprintable_and_pipe(std::basic_string<char>& str,
                                                                           char replacement)
        {
                const char MIN  = 0x20;
                const char PIPE = 0x7c;
                std::basic_string<char>::size_type len = str.size();
                for(std::basic_string<char>::size_type ii = 0; ii < len; ++ii)
                {
                        if( (str[ii] < MIN) || (str[ii] == PIPE) )
                        {
                                str[ii] = replacement;
                        }
                }
        }

        void replace_nonprintable_and_pipe(std::basic_string<llwchar>& str,
                                                                           llwchar replacement)
        {
                const llwchar MIN  = 0x20;
                const llwchar MAX  = 0x7f;
                const llwchar PIPE = 0x7c;
                std::basic_string<llwchar>::size_type len = str.size();
                for(std::basic_string<llwchar>::size_type ii = 0; ii < len; ++ii)
                {
                        if( (str[ii] < MIN) || (str[ii] > MAX) || (str[ii] == PIPE) )
                        {
                                str[ii] = replacement;
                        }
                }
        }
}


// Testing

#ifdef _DEBUG

template<class T> 
void LLStringBase<T>::testHarness()
{
        LLString s1;
        
        llassert( s1.c_str() == NULL );
        llassert( s1.size() == 0 );
        llassert( s1.empty() );
        
        LLString s2( "hello");
        llassert( !strcmp( s2.c_str(), "hello" ) );
        llassert( s2.size() == 5 ); 
        llassert( !s2.empty() );
        LLString s3( s2 );

        llassert( "hello" == s2 );
        llassert( s2 == "hello" );
        llassert( s2 > "gello" );
        llassert( "gello" < s2 );
        llassert( "gello" != s2 );
        llassert( s2 != "gello" );

        LLString s4 = s2;
        llassert( !s4.empty() );
        s4.empty();
        llassert( s4.empty() );
        
        LLString s5("");
        llassert( s5.empty() );
        
        llassert( isValidIndex(s5, 0) );
        llassert( !isValidIndex(s5, 1) );
        
        s3 = s2;
        s4 = "hello again";
        
        s4 += "!";
        s4 += s4;
        llassert( s4 == "hello again!hello again!" );
        
        
        LLString s6 = s2 + " " + s2;
        LLString s7 = s6;
        llassert( s6 == s7 );
        llassert( !( s6 != s7) );
        llassert( !(s6 < s7) );
        llassert( !(s6 > s7) );
        
        llassert( !(s6 == "hi"));
        llassert( s6 == "hello hello");
        llassert( s6 < "hi");
        
        llassert( s6[1] == 'e' );
        s6[1] = 'f';
        llassert( s6[1] == 'f' );
        
        s2.erase( 4, 1 );
        llassert( s2 == "hell");
        s2.insert( 0, 'y' );
        llassert( s2 == "yhell");
        s2.erase( 1, 3 );
        llassert( s2 == "yl");
        s2.insert( 1, "awn, don't yel");
        llassert( s2 == "yawn, don't yell");
        
        LLString s8 = s2.substr( 6, 5 );
        llassert( s8 == "don't"  );
        
        LLString s9 = "   \t\ntest  \t\t\n  ";
        trim(s9);
        llassert( s9 == "test"  );

        s8 = "abc123&*(ABC";

        s9 = s8;
        toUpper(s9);
        llassert( s9 == "ABC123&*(ABC"  );

        s9 = s8;
        toLower(s9);
        llassert( s9 == "abc123&*(abc"  );


        LLString s10( 10, 'x' );
        llassert( s10 == "xxxxxxxxxx" );

        LLString s11( "monkey in the middle", 7, 2 );
        llassert( s11 == "in" );

        LLString s12;  //empty
        s12 += "foo";
        llassert( s12 == "foo" );

        LLString s13;  //empty
        s13 += 'f';
        llassert( s13 == "f" );
}


#endif  // _DEBUG

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