1 /* Concatenate variable number of strings.
2 Copyright (C) 1991-2023 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