/* Concatenate variable number of strings.

   Copyright (C) 1991-2025 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., 51 Franklin Street - Fifth Floor,

Boston, MA 02110-1301, USA.  */

/*

@deftypefn Extension char* concat (const char *@var{s1}, const char *@var{s2}, @

  @dots{}, @code{NULL})

Concatenate zero or more of strings and return the result in freshly

@code{xmalloc}ed memory.  The argument list is terminated by the first

@code{NULL} pointer encountered.  Pointers to empty strings are ignored.

@end deftypefn

*/

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include "ansidecl.h"

#include "libiberty.h"

#include <sys/types.h>    /* size_t */

#include <stdarg.h>

# if HAVE_STRING_H

#  include <string.h>

# else

#  if HAVE_STRINGS_H

#   include <strings.h>

#  endif

# endif

#if HAVE_STDLIB_H

#include <stdlib.h>

#endif

static inline unsigned long vconcat_length (const char *, va_list);

static inline unsigned long

vconcat_length (const char *first, va_list args)

{

  unsigned long length = 0;

  const char *arg;

  for (arg = first; arg ; arg = va_arg (args, const char *))

    length += strlen (arg);

  return length;

}

static inline char *

vconcat_copy (char *dst, const char *first, va_list args)

{

  char *end = dst;

  const char *arg;

  for (arg = first; arg ; arg = va_arg (args, const char *))

    {

      unsigned long length = strlen (arg);

      memcpy (end, arg, length);

      end += length;

    }

  *end = '\000';

  return dst;

}

/* @undocumented concat_length */

unsigned long

concat_length (const char *first, ...)

{

  unsigned long length;

  va_list args;

  va_start (args, first);

  length = vconcat_length (first, args);

  va_end (args);

  return length;

}

/* @undocumented concat_copy */

char *

concat_copy (char *dst, const char *first, ...)

{

  char *save_dst;

  va_list args;

  va_start (args, first);

  vconcat_copy (dst, first, args);

  save_dst = dst; /* With K&R C, dst goes out of scope here.  */

  va_end (args);

  return save_dst;

}

#ifdef __cplusplus

extern "C" {

#endif /* __cplusplus */

char *libiberty_concat_ptr;

#ifdef __cplusplus

}

#endif /* __cplusplus */

/* @undocumented concat_copy2 */

char *

concat_copy2 (const char *first, ...)

{

  va_list args;

  va_start (args, first);

  vconcat_copy (libiberty_concat_ptr, first, args);

  va_end (args);

  return libiberty_concat_ptr;

}

char *

concat (const char *first, ...)

{

  char *newstr;

  va_list args;

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

  va_start (args, first);

  newstr = XNEWVEC (char, vconcat_length (first, args) + 1);

  va_end (args);

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

  va_start (args, first);

  vconcat_copy (newstr, first, args);

  va_end (args);

  return newstr;

}

/*

@deftypefn Extension char* reconcat (char *@var{optr}, const char *@var{s1}, @

  @dots{}, @code{NULL})

Same as @code{concat}, except that if @var{optr} is not @code{NULL} it

is freed after the string is created.  This is intended to be useful

when you're extending an existing string or building up a string in a

loop:

@example

  str = reconcat (str, "pre-", str, NULL);

@end example

@end deftypefn

*/

char *

reconcat (char *optr, const char *first, ...)

{

  char *newstr;

  va_list args;

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

  va_start (args, first);

  newstr = XNEWVEC (char, vconcat_length (first, args) + 1);

  va_end (args);

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

  va_start (args, first);

  vconcat_copy (newstr, first, args);

  if (optr) /* Done before VA_CLOSE so optr stays in scope for K&R C.  */

    free (optr);

  va_end (args);

  return newstr;

}

#ifdef MAIN

#define NULLP (char *)0

/* Simple little test driver. */

#include <stdio.h>

int

main (void)

{

  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