Revert of Update re2

third_party/re2/util/strutil.cc

 // Copyright 1999-2005 The RE2 Authors.  All Rights Reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 #include "util/util.h"
 #include "re2/stringpiece.h"
 
 namespace re2 {
 
 // ----------------------------------------------------------------------
 // CEscapeString()
 //    Copies 'src' to 'dest', escaping dangerous characters using
 //    C-style escape sequences.  'src' and 'dest' should not overlap.
 //    Returns the number of bytes written to 'dest' (not including the \0)
 //    or -1 if there was insufficient space.
 // ----------------------------------------------------------------------
 int CEscapeString(const char* src, int src_len, char* dest,
                   int dest_len) {
   const char* src_end = src + src_len;
   int used = 0;
 
   for (; src < src_end; src++) {
-    if (dest_len - used < 2)   // space for two-character escape
+    if (dest_len - used < 2)   // Need space for two letter escape
       return -1;
 
     unsigned char c = *src;
     switch (c) {
       case '\n': dest[used++] = '\\'; dest[used++] = 'n';  break;
       case '\r': dest[used++] = '\\'; dest[used++] = 'r';  break;
       case '\t': dest[used++] = '\\'; dest[used++] = 't';  break;
       case '\"': dest[used++] = '\\'; dest[used++] = '\"'; break;
       case '\'': dest[used++] = '\\'; dest[used++] = '\''; break;
       case '\\': dest[used++] = '\\'; dest[used++] = '\\'; break;
       default:
         // Note that if we emit \xNN and the src character after that is a hex
         // digit then that digit must be escaped too to prevent it being
         // interpreted as part of the character code by C.
         if (c < ' ' || c > '~') {
-          if (dest_len - used < 5)   // space for four-character escape + \0
+          if (dest_len - used < 4) // need space for 4 letter escape
             return -1;
-#if !defined(_WIN32)
-          snprintf(dest + used, 5, "\\%03o", c);
-#else
-          // On Windows, the function takes 4+VA arguments, not 3+VA. With an
-          // array, the buffer size will be inferred, but not with a pointer.
-          snprintf(dest + used, 5, _TRUNCATE, "\\%03o", c);
-#endif
+          sprintf(dest + used, "\\%03o", c);
           used += 4;
         } else {
           dest[used++] = c; break;
         }
     }
   }
 
   if (dest_len - used < 1)   // make sure that there is room for \0
     return -1;
 
   dest[used] = '\0';   // doesn't count towards return value though
   return used;
 }
 
 
 // ----------------------------------------------------------------------
 // CEscape()
 //    Copies 'src' to result, escaping dangerous characters using
-//    C-style escape sequences.  'src' and 'dest' should not overlap.
+//    C-style escape sequences.  'src' and 'dest' should not overlap. 
 // ----------------------------------------------------------------------
 string CEscape(const StringPiece& src) {
   const int dest_length = src.size() * 4 + 1; // Maximum possible expansion
   char* dest = new char[dest_length];
   const int len = CEscapeString(src.data(), src.size(),
                                 dest, dest_length);
   string s = string(dest, len);
   delete[] dest;
   return s;
 }
 
 string PrefixSuccessor(const StringPiece& prefix) {
   // We can increment the last character in the string and be done
   // unless that character is 255, in which case we have to erase the
   // last character and increment the previous character, unless that
   // is 255, etc. If the string is empty or consists entirely of
   // 255's, we just return the empty string.
   bool done = false;
   string limit(prefix.data(), prefix.size());
-  int index = static_cast<int>(limit.size()) - 1;
+  int index = limit.length() - 1;
   while (!done && index >= 0) {
     if ((limit[index]&255) == 255) {
       limit.erase(index);
       index--;
     } else {
       limit[index]++;
       done = true;
     }
   }
   if (!done) {
     return "";
   } else {
     return limit;
   }
 }
 
 }  // namespace re2