lib/libiberty/concat.c

   1 /*
   2  * Copyright (c) 2004 Joerg Sonnenberger <joerg@bec.de>
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  *
  25  * $DragonFly: src/lib/libiberty/concat.c,v 1.1 2004/10/23 12:15:21 joerg Exp $
  26  */
  27
  28 #include <err.h>
  29 #include <libiberty.h>
  30 #include <string.h>
  31 #include <stdarg.h>
  32 #include <stdlib.h>
  33
  34 static size_t
  35 concat_strlen(const char *str1, va_list ap)
  36 {
  37         size_t len, new_len;
  38
  39         len = strlen(str1);
  40
  41         while ((str1 = va_arg(ap, const char *)) != NULL) {
  42                 new_len = len + strlen(str1);
  43                 if (new_len < len)
  44                         errx(EXIT_FAILURE, "overflow in %s", __func__);
  45                 len = new_len;
  46         }
  47         return(len);
  48 }
  49
  50 static void
  51 concat_copy(char *buf, const char *str1, va_list ap)
  52 {
  53         size_t len;
  54
  55         do {
  56             len = strlen(str1);
  57             memcpy(buf, str1, len);
  58             buf += len;
  59         } while ((str1 = va_arg(ap, const char *)) != NULL);
  60
  61         *buf = '\0';
  62 }
  63
  64 char *
  65 concat(const char *str1, ...)
  66 {
  67         va_list ap;
  68         size_t len;
  69         char *str;
  70
  71         if (str1 == NULL)
  72                 return(xstrdup(""));
  73
  74         va_start(ap, str1);
  75         len = concat_strlen(str1, ap);
  76         va_end(ap);
  77
  78         str = xmalloc(len + 1);
  79         va_start(ap, str1);
  80         concat_copy(str, str1, ap);
  81         va_end(ap);
  82
  83         return(str);
  84 }
  85
  86 char *
  87 reconcat(char *str1, ...)
  88 {
  89         va_list ap;
  90         size_t len;
  91         char *str;
  92
  93         va_start(ap, str1);
  94         len = concat_strlen("", ap);
  95         va_end(ap);
  96
  97         str = xmalloc(len + 1);
  98         va_start(ap, str1);
  99         concat_copy(str, "", ap);
 100         va_end(ap);
 101
 102         free(str1);
 103
 104         return(str);
 105 }