1 /* Concatenate variable number of strings.
2    Copyright (C) 1991-2020 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., 51 Franklin Street - Fifth Floor,
19 Boston, MA 02110-1301, USA.  */
20 
21 
22 /*
23 
24 @deftypefn Extension char* concat (const char *@var{s1}, const char *@var{s2}, @
25   @dots{}, @code{NULL})
26 
27 Concatenate zero or more of strings and return the result in freshly
28 @code{xmalloc}ed memory.  The argument list is terminated by the first
29 @code{NULL} pointer encountered.  Pointers to empty strings are ignored.
30 
31 @end deftypefn
32 
33 */
34 
35 
36 #ifdef HAVE_CONFIG_H
37 #include "config.h"
38 #endif
39 #include "ansidecl.h"
40 #include "libiberty.h"
41 #include <sys/types.h>		/* size_t */
42 
43 #include <stdarg.h>
44 
45 # if HAVE_STRING_H
46 #  include <string.h>
47 # else
48 #  if HAVE_STRINGS_H
49 #   include <strings.h>
50 #  endif
51 # endif
52 
53 #if HAVE_STDLIB_H
54 #include <stdlib.h>
55 #endif
56 
57 static inline unsigned long vconcat_length (const char *, va_list);
58 static inline unsigned long
59 vconcat_length (const char *first, va_list args)
60 {
61   unsigned long length = 0;
62   const char *arg;
63 
64   for (arg = first; arg ; arg = va_arg (args, const char *))
65     length += strlen (arg);
66 
67   return length;
68 }
69 
70 static inline char *
71 vconcat_copy (char *dst, const char *first, va_list args)
72 {
73   char *end = dst;
74   const char *arg;
75 
76   for (arg = first; arg ; arg = va_arg (args, const char *))
77     {
78       unsigned long length = strlen (arg);
79       memcpy (end, arg, length);
80       end += length;
81     }
82   *end = '\000';
83 
84   return dst;
85 }
86 
87 /* @undocumented concat_length */
88 
89 unsigned long
90 concat_length (const char *first, ...)
91 {
92   unsigned long length;
93   va_list args;
94 
95   va_start (args, first);
96   length = vconcat_length (first, args);
97   va_end (args);
98 
99   return length;
100 }
101 
102 /* @undocumented concat_copy */
103 
104 char *
105 concat_copy (char *dst, const char *first, ...)
106 {
107   char *save_dst;
108   va_list args;
109 
110   va_start (args, first);
111   vconcat_copy (dst, first, args);
112   save_dst = dst; /* With K&R C, dst goes out of scope here.  */
113   va_end (args);
114 
115   return save_dst;
116 }
117 
118 #ifdef __cplusplus
119 extern "C" {
120 #endif /* __cplusplus */
121 char *libiberty_concat_ptr;
122 #ifdef __cplusplus
123 }
124 #endif /* __cplusplus */
125 
126 /* @undocumented concat_copy2 */
127 
128 char *
129 concat_copy2 (const char *first, ...)
130 {
131   va_list args;
132   va_start (args, first);
133   vconcat_copy (libiberty_concat_ptr, first, args);
134   va_end (args);
135 
136   return libiberty_concat_ptr;
137 }
138 
139 char *
140 concat (const char *first, ...)
141 {
142   char *newstr;
143   va_list args;
144 
145   /* First compute the size of the result and get sufficient memory.  */
146   va_start (args, first);
147   newstr = XNEWVEC (char, vconcat_length (first, args) + 1);
148   va_end (args);
149 
150   /* Now copy the individual pieces to the result string. */
151   va_start (args, first);
152   vconcat_copy (newstr, first, args);
153   va_end (args);
154 
155   return newstr;
156 }
157 
158 /*
159 
160 @deftypefn Extension char* reconcat (char *@var{optr}, const char *@var{s1}, @
161   @dots{}, @code{NULL})
162 
163 Same as @code{concat}, except that if @var{optr} is not @code{NULL} it
164 is freed after the string is created.  This is intended to be useful
165 when you're extending an existing string or building up a string in a
166 loop:
167 
168 @example
169   str = reconcat (str, "pre-", str, NULL);
170 @end example
171 
172 @end deftypefn
173 
174 */
175 
176 char *
177 reconcat (char *optr, const char *first, ...)
178 {
179   char *newstr;
180   va_list args;
181 
182   /* First compute the size of the result and get sufficient memory.  */
183   va_start (args, first);
184   newstr = XNEWVEC (char, vconcat_length (first, args) + 1);
185   va_end (args);
186 
187   /* Now copy the individual pieces to the result string. */
188   va_start (args, first);
189   vconcat_copy (newstr, first, args);
190   if (optr) /* Done before VA_CLOSE so optr stays in scope for K&R C.  */
191     free (optr);
192   va_end (args);
193 
194   return newstr;
195 }
196 
197 #ifdef MAIN
198 #define NULLP (char *)0
199 
200 /* Simple little test driver. */
201 
202 #include <stdio.h>
203 
204 int
205 main (void)
206 {
207   printf ("\"\" = \"%s\"\n", concat (NULLP));
208   printf ("\"a\" = \"%s\"\n", concat ("a", NULLP));
209   printf ("\"ab\" = \"%s\"\n", concat ("a", "b", NULLP));
210   printf ("\"abc\" = \"%s\"\n", concat ("a", "b", "c", NULLP));
211   printf ("\"abcd\" = \"%s\"\n", concat ("ab", "cd", NULLP));
212   printf ("\"abcde\" = \"%s\"\n", concat ("ab", "c", "de", NULLP));
213   printf ("\"abcdef\" = \"%s\"\n", concat ("", "a", "", "bcd", "ef", NULLP));
214   return 0;
215 }
216 
217 #endif
218