Suggested approach to fixing ninja getcwd

fixing_ninja.cc

Previous code like this:

--------------------------

  bool first = true;
  vector<char> cwd;
  char* success = NULL;

  do {
    cwd.resize(cwd.size() + 1024);
    errno = 0;
    success = getcwd(&cwd[0], cwd.size());
  } while (!success && errno == ERANGE);
  if (!success) {
    Error("cannot determine working directory: %s", strerror(errno));
    return 1;
  }
--------------------------

Something like this I guess:

--------------------------



  bool first = true;
  vector<char> cwd;
  
#if defined(__sgi)
  errno = 0;
  char * libcgetcwd = getcwd(NULL,-1);
  if( libcgetcwd == NULL ) {
    Error("cannot determine working directory: %s", strerror(errno));
    return 1;
  } else {
    cwd.resize(strlen(libcgetcwd)+1);
    strcpy(&cwd[0],libcgetcwd);
    free(libcgetcwd);
  }
  errno = 0;
#else
  char * success;
  do {
    cwd.resize(cwd.size() + 1024);
    errno = 0;
    success = getcwd(&cwd[0], cwd.size());
  } while (!success && errno == ERANGE);
  if (!success) {
    Error("cannot determine working directory: %s", strerror(errno));
    return 1;
  }
#endif