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 @deftypefn Extension char* concat (const char *@var{s1}, const char *@var{s2}, @dots{}, @code{NULL})
  25
  26 Concatenate zero or more of strings and return the result in freshly
  27 @code{xmalloc}ed memory.  Returns @code{NULL} if insufficient memory is
  28 available.  The argument list is terminated by the first @code{NULL}
  29 pointer encountered.  Pointers to empty strings are ignored.
  30
  31 @end deftypefn
  32
  33 NOTES
  34
  35         This function uses xmalloc() which is expected to be a front end
  36         function to malloc() that deals with low memory situations.  In
  37         typical use, if malloc() returns NULL then xmalloc() diverts to an
  38         error handler routine which never returns, and thus xmalloc will
  39         never return a NULL pointer.  If the client application wishes to
  40         deal with low memory situations itself, it should supply an xmalloc
  41         that just directly invokes malloc and blindly returns whatever
  42         malloc returns.
  43
  44 */
  45
  46
  47 #ifdef HAVE_CONFIG_H
  48 #include "config.h"
  49 #endif
  50 #include "ansidecl.h"
  51 #include "libiberty.h"
  52 #include <sys/types.h>          /* size_t */
  53
  54 #ifdef ANSI_PROTOTYPES
  55 #include <stdarg.h>
  56 #else
  57 #include <varargs.h>
  58 #endif
  59
  60 # if HAVE_STRING_H
  61 #  include <string.h>
  62 # else
  63 #  if HAVE_STRINGS_H
  64 #   include <strings.h>
  65 #  endif
  66 # endif
  67
  68 #if HAVE_STDLIB_H
  69 #include <stdlib.h>
  70 #endif
  71
  72 static inline unsigned long vconcat_length PARAMS ((const char *, va_list));
  73 static inline unsigned long
  74 vconcat_length (first, args)
  75      const char *first;
  76      va_list args;
  77 {
  78   unsigned long length = 0;
  79   const char *arg;
  80
  81   for (arg = first; arg ; arg = va_arg (args, const char *))
  82     length += strlen (arg);
  83
  84   return length;
  85 }
  86
  87 static inline char *vconcat_copy PARAMS ((char *, const char *, va_list));
  88 static inline char *
  89 vconcat_copy (dst, first, args)
  90      char *dst;
  91      const char *first;
  92      va_list args;
  93 {
  94   char *end = dst;
  95   const char *arg;
  96
  97   for (arg = first; arg ; arg = va_arg (args, const char *))
  98     {
  99       unsigned long length = strlen (arg);
 100       memcpy (end, arg, length);
 101       end += length;
 102     }
 103   *end = '\000';
 104
 105   return dst;
 106 }
 107
 108 /* @undocumented concat_length */
 109
 110 unsigned long
 111 concat_length VPARAMS ((const char *first, ...))
 112 {
 113   unsigned long length;
 114
 115   VA_OPEN (args, first);
 116   VA_FIXEDARG (args, const char *, first);
 117   length = vconcat_length (first, args);
 118   VA_CLOSE (args);
 119
 120   return length;
 121 }
 122
 123 /* @undocumented concat_copy */
 124
 125 char *
 126 concat_copy VPARAMS ((char *dst, const char *first, ...))
 127 {
 128   char *save_dst;
 129
 130   VA_OPEN (args, first);
 131   VA_FIXEDARG (args, char *, dst);
 132   VA_FIXEDARG (args, const char *, first);
 133   vconcat_copy (dst, first, args);
 134   save_dst = dst; /* With K&R C, dst goes out of scope here.  */
 135   VA_CLOSE (args);
 136
 137   return save_dst;
 138 }
 139
 140 char *libiberty_concat_ptr;
 141
 142 /* @undocumented concat_copy2 */
 143
 144 char *
 145 concat_copy2 VPARAMS ((const char *first, ...))
 146 {
 147   VA_OPEN (args, first);
 148   VA_FIXEDARG (args, const char *, first);
 149   vconcat_copy (libiberty_concat_ptr, first, args);
 150   VA_CLOSE (args);
 151
 152   return libiberty_concat_ptr;
 153 }
 154
 155 char *
 156 concat VPARAMS ((const char *first, ...))
 157 {
 158   char *newstr;
 159
 160   /* First compute the size of the result and get sufficient memory.  */
 161   VA_OPEN (args, first);
 162   VA_FIXEDARG (args, const char *, first);
 163   newstr = (char *) xmalloc (vconcat_length (first, args) + 1);
 164   VA_CLOSE (args);
 165
 166   /* Now copy the individual pieces to the result string. */
 167   VA_OPEN (args, first);
 168   VA_FIXEDARG (args, const char *, first);
 169   vconcat_copy (newstr, first, args);
 170   VA_CLOSE (args);
 171
 172   return newstr;
 173 }
 174
 175 /*
 176
 177 @deftypefn Extension char* reconcat (char *@var{optr}, const char *@var{s1}, @dots{}, @code{NULL})
 178
 179 Same as @code{concat}, except that if @var{optr} is not @code{NULL} it
 180 is freed after the string is created.  This is intended to be useful
 181 when you're extending an existing string or building up a string in a
 182 loop:
 183
 184 @example
 185   str = reconcat (str, "pre-", str, NULL);
 186 @end example
 187
 188 @end deftypefn
 189
 190 */
 191
 192 char *
 193 reconcat VPARAMS ((char *optr, const char *first, ...))
 194 {
 195   char *newstr;
 196
 197   /* First compute the size of the result and get sufficient memory.  */
 198   VA_OPEN (args, first);
 199   VA_FIXEDARG (args, char *, optr);
 200   VA_FIXEDARG (args, const char *, first);
 201   newstr = (char *) xmalloc (vconcat_length (first, args) + 1);
 202   VA_CLOSE (args);
 203
 204   /* Now copy the individual pieces to the result string. */
 205   VA_OPEN (args, first);
 206   VA_FIXEDARG (args, char *, optr);
 207   VA_FIXEDARG (args, const char *, first);
 208   vconcat_copy (newstr, first, args);
 209   if (optr) /* Done before VA_CLOSE so optr stays in scope for K&R C.  */
 210     free (optr);
 211   VA_CLOSE (args);
 212
 213   return newstr;
 214 }
 215
 216 #ifdef MAIN
 217 #define NULLP (char *)0
 218
 219 /* Simple little test driver. */
 220
 221 #include <stdio.h>
 222
 223 int
 224 main ()
 225 {
 226   printf ("\"\" = \"%s\"\n", concat (NULLP));
 227   printf ("\"a\" = \"%s\"\n", concat ("a", NULLP));
 228   printf ("\"ab\" = \"%s\"\n", concat ("a", "b", NULLP));
 229   printf ("\"abc\" = \"%s\"\n", concat ("a", "b", "c", NULLP));
 230   printf ("\"abcd\" = \"%s\"\n", concat ("ab", "cd", NULLP));
 231   printf ("\"abcde\" = \"%s\"\n", concat ("ab", "c", "de", NULLP));
 232   printf ("\"abcdef\" = \"%s\"\n", concat ("", "a", "", "bcd", "ef", NULLP));
 233   return 0;
 234 }
 235
 236 #endif