libiberty/concat.c

   1 /* Concatenate variable number of strings.
   2    Copyright (C) 1991, 1994, 2001 Free Software Foundation, Inc.
   3    Written by Fred Fish @ Cygnus Support
   4
   5 This file is part of the libiberty library.
   6 Libiberty is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU Library General Public
   8 License as published by the Free Software Foundation; either
   9 version 2 of the License, or (at your option) any later version.
  10
  11 Libiberty is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 Library General Public License for more details.
  15
  16 You should have received a copy of the GNU Library General Public
  17 License along with libiberty; see the file COPYING.LIB.  If
  18 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 /*
  23
  24 NAME
  25
  26         concat -- concatenate a variable number of strings
  27
  28 SYNOPSIS
  29
  30         #include <varargs.h>
  31
  32         char *concat (s1, s2, s3, ..., NULL)
  33
  34 DESCRIPTION
  35
  36         Concatenate a variable number of strings and return the result
  37         in freshly malloc'd memory.
  38
  39         Returns NULL if insufficient memory is available.  The argument
  40         list is terminated by the first NULL pointer encountered.  Pointers
  41         to empty strings are ignored.
  42
  43 NOTES
  44
  45         This function uses xmalloc() which is expected to be a front end
  46         function to malloc() that deals with low memory situations.  In
  47         typical use, if malloc() returns NULL then xmalloc() diverts to an
  48         error handler routine which never returns, and thus xmalloc will
  49         never return a NULL pointer.  If the client application wishes to
  50         deal with low memory situations itself, it should supply an xmalloc
  51         that just directly invokes malloc and blindly returns whatever
  52         malloc returns.
  53 */
  54
  55
  56 #ifdef HAVE_CONFIG_H
  57 #include "config.h"
  58 #endif
  59 #include "ansidecl.h"
  60 #include "libiberty.h"
  61 #include <sys/types.h>          /* size_t */
  62
  63 #ifdef ANSI_PROTOTYPES
  64 #include <stdarg.h>
  65 #else
  66 #include <varargs.h>
  67 #endif
  68
  69 # if HAVE_STRING_H
  70 #  include <string.h>
  71 # else
  72 #  if HAVE_STRINGS_H
  73 #   include <strings.h>
  74 #  endif
  75 # endif
  76
  77 char *
  78 concat VPARAMS ((const char *first, ...))
  79 {
  80   register size_t length;
  81   register char *newstr;
  82   register char *end;
  83   register const char *arg;
  84
  85   /* First compute the size of the result and get sufficient memory.  */
  86   VA_OPEN (args, first);
  87   VA_FIXEDARG (args, const char *, first);
  88
  89   length = 0;
  90   for (arg = first; arg ; arg = va_arg (args, const char *))
  91     length += strlen (arg);
  92
  93   VA_CLOSE (args);
  94
  95   newstr = (char *) xmalloc (length + 1);
  96
  97   /* Now copy the individual pieces to the result string. */
  98   VA_OPEN (args, first);
  99   VA_FIXEDARG (args, const char *, first);
 100
 101   end = newstr;
 102   for (arg = first; arg ; arg = va_arg (args, const char *))
 103     {
 104       length = strlen (arg);
 105       memcpy (end, arg, length);
 106       end += length;
 107     }
 108   *end = '\000';
 109   VA_CLOSE (args);
 110
 111   return newstr;
 112 }
 113
 114 #ifdef MAIN
 115 #define NULLP (char *)0
 116
 117 /* Simple little test driver. */
 118
 119 #include <stdio.h>
 120
 121 int
 122 main ()
 123 {
 124   printf ("\"\" = \"%s\"\n", concat (NULLP));
 125   printf ("\"a\" = \"%s\"\n", concat ("a", NULLP));
 126   printf ("\"ab\" = \"%s\"\n", concat ("a", "b", NULLP));
 127   printf ("\"abc\" = \"%s\"\n", concat ("a", "b", "c", NULLP));
 128   printf ("\"abcd\" = \"%s\"\n", concat ("ab", "cd", NULLP));
 129   printf ("\"abcde\" = \"%s\"\n", concat ("ab", "c", "de", NULLP));
 130   printf ("\"abcdef\" = \"%s\"\n", concat ("", "a", "", "bcd", "ef", NULLP));
 131   return 0;
 132 }
 133
 134 #endif