[RFC] libstdc++/9817 or "passing C++ strings to C functions"

[Pétur Runólfsson]

Paolo Carlini wrote:
> Other proposals?

I think something like this may work (untested code ahead):

const char* p = str1.c_str();
const char* pend = str1.c_str() + str1.length();
const char* q = str2.c_str();
const char* qend = str2.c_str() + str2.length();

for (;;)
{
  int ret = strcoll(p, q);
  if (ret)
    return ret;
  p += strlen(p);
  q += strlen(q);
  if (p == pend && q == qend)
    return 0;
  else if (p == pend)
    return -1;
  else if (q == qend)
    return 1;
  ++p;
  ++q;
}

This breaks the strings into chunks separated by \0 and then
compares the chunks until it finds a pair that compares unequal,
or one or both strings are empty. Note that strlen has to be
called for both strings since strings of different length can
collate equal.

Petur