Test if supplied string is of the form of a valid IP address (four numbers between 0 and 255 separated by a period)

Declared in file: hzTextproc.h
Defined in file : hzIpaddr.cpp

Function Logic:

Function body:

bool IsIPAddr (uint32_t& nIpValue)const char* cpIpa, 
{
   //  Category: Text Processing
   //  
   //  Test if supplied string is of the form of a valid IP address (four numbers between 0 and 255 separated by a period)
   //  
   //  Arguments: 1) nIpValue The IP value, set if supplied string is of the form
   //     2) cpIpa The string to be tested
   //  
   //  Returns: True If the supplied string amounts to a valid IP address
   //     False If it doesn't
   const char* i ;             //  Text IP address iterator
   uint32_t    nVal = 0;       //  32-bit IP address value
   uint32_t    nTmp ;          //  IP segment value
   int32_t     nNos = 0;       //  Count of IP numeric segments
   nIpValue = IPADDR_BAD ;
   if (!cpIpa)     return false ;
   if (!cpIpa[0])  return false ;
   for (i = cpIpa ; *i ; i++)
   {
       if (*i < ''0''||*i > ''9'')
           return false ;
       for (nTmp = 0; *i >&eq; ''0''&&*i <&eq; ''9'';i++)
           { nTmp *= 10;nTmp += (*i - ''0'');}
       if (nTmp > 255)
           return false ;
       nVal *= 256;
       nVal += nTmp ;
       nNos++ ;
       if (*i == 0|| *i == CHAR_COMMA)
           break ;
       if (*i != CHAR_PERIOD)
           return false ;
   }
   if (nNos != 4)
       return false ;
   nIpValue = nVal ;
   return true ;
}