source: trunk/src/binutils/libiberty/concat.c@ 108

/* Concatenate variable number of strings.
   Copyright (C) 1991, 1994 Free Software Foundation, Inc.
   Written by Fred Fish @ Cygnus Support

This file is part of the libiberty library.
Libiberty is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.

Libiberty is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with libiberty; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


/*

NAME

        concat -- concatenate a variable number of strings

SYNOPSIS

        #include <varargs.h>

        char *concat (s1, s2, s3, ..., NULL)

DESCRIPTION

        Concatenate a variable number of strings and return the result
        in freshly malloc'd memory.

        Returns NULL if insufficient memory is available.  The argument
        list is terminated by the first NULL pointer encountered.  Pointers
        to empty strings are ignored.

NOTES

        This function uses xmalloc() which is expected to be a front end
        function to malloc() that deals with low memory situations.  In
        typical use, if malloc() returns NULL then xmalloc() diverts to an
        error handler routine which never returns, and thus xmalloc will
        never return a NULL pointer.  If the client application wishes to
        deal with low memory situations itself, it should supply an xmalloc
        that just directly invokes malloc and blindly returns whatever
        malloc returns.
*/


#include "ansidecl.h"
#include "libiberty.h"

#ifdef ANSI_PROTOTYPES
#include <stdarg.h>
#else
#include <varargs.h>
#endif

#ifdef __STDC__
#include <stddef.h>
extern size_t strlen (const char *s);
#else
extern int strlen ();
#endif

#define NULLP (char *)0

/* VARARGS */
#ifdef ANSI_PROTOTYPES
char *
concat (const char *first, ...)
#else
char *
concat (va_alist)
     va_dcl
#endif
{
  register int length;
  register char *newstr;
  register char *end;
  register const char *arg;
  va_list args;
#ifndef ANSI_PROTOTYPES
  const char *first;
#endif

  /* First compute the size of the result and get sufficient memory. */

#ifdef ANSI_PROTOTYPES
  va_start (args, first);
#else
  va_start (args);
  first = va_arg (args, const char *);
#endif

  if (first == NULLP)
    length = 0;
  else
    {
      length = strlen (first);
      while ((arg = va_arg (args, const char *)) != NULLP)
        {
          length += strlen (arg);
        }
    }
  newstr = (char *) xmalloc (length + 1);
  va_end (args);

  /* Now copy the individual pieces to the result string. */

  if (newstr != NULLP)
    {
#ifdef ANSI_PROTOTYPES
      va_start (args, first);
#else
      va_start (args);
      first = va_arg (args, const char *);
#endif
      end = newstr;
      if (first != NULLP)
        {
          arg = first;
          while (*arg)
            {
              *end++ = *arg++;
            }
          while ((arg = va_arg (args, const char *)) != NULLP)
            {
              while (*arg)
                {
                  *end++ = *arg++;
                }
            }
        }
      *end = '\000';
      va_end (args);
    }

  return (newstr);
}

#ifdef MAIN

/* Simple little test driver. */

#include <stdio.h>

int
main ()
{
  printf ("\"\" = \"%s\"\n", concat (NULLP));
  printf ("\"a\" = \"%s\"\n", concat ("a", NULLP));
  printf ("\"ab\" = \"%s\"\n", concat ("a", "b", NULLP));
  printf ("\"abc\" = \"%s\"\n", concat ("a", "b", "c", NULLP));
  printf ("\"abcd\" = \"%s\"\n", concat ("ab", "cd", NULLP));
  printf ("\"abcde\" = \"%s\"\n", concat ("ab", "c", "de", NULLP));
  printf ("\"abcdef\" = \"%s\"\n", concat ("", "a", "", "bcd", "ef", NULLP));
  return 0;
}

#endif