xref: /openbsd/gnu/lib/libiberty/src/concat.c (revision 20fce977)
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., 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}, @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 #include <stdarg.h>
55 
56 # if HAVE_STRING_H
57 #  include <string.h>
58 # else
59 #  if HAVE_STRINGS_H
60 #   include <strings.h>
61 #  endif
62 # endif
63 
64 #if HAVE_STDLIB_H
65 #include <stdlib.h>
66 #endif
67 
68 static inline unsigned long vconcat_length (const char *, va_list);
69 static inline unsigned long
vconcat_length(const char * first,va_list args)70 vconcat_length (const char *first, va_list args)
71 {
72   unsigned long length = 0;
73   const char *arg;
74 
75   for (arg = first; arg ; arg = va_arg (args, const char *))
76     length += strlen (arg);
77 
78   return length;
79 }
80 
81 static inline char *
vconcat_copy(char * dst,const char * first,va_list args)82 vconcat_copy (char *dst, const char *first, va_list args)
83 {
84   char *end = dst;
85   const char *arg;
86 
87   for (arg = first; arg ; arg = va_arg (args, const char *))
88     {
89       unsigned long length = strlen (arg);
90       memcpy (end, arg, length);
91       end += length;
92     }
93   *end = '\000';
94 
95   return dst;
96 }
97 
98 /* @undocumented concat_length */
99 
100 unsigned long
concat_length(const char * first,...)101 concat_length (const char *first, ...)
102 {
103   unsigned long length;
104 
105   VA_OPEN (args, first);
106   VA_FIXEDARG (args, const char *, first);
107   length = vconcat_length (first, args);
108   VA_CLOSE (args);
109 
110   return length;
111 }
112 
113 /* @undocumented concat_copy */
114 
115 char *
concat_copy(char * dst,const char * first,...)116 concat_copy (char *dst, const char *first, ...)
117 {
118   char *save_dst;
119 
120   VA_OPEN (args, first);
121   VA_FIXEDARG (args, char *, dst);
122   VA_FIXEDARG (args, const char *, first);
123   vconcat_copy (dst, first, args);
124   save_dst = dst; /* With K&R C, dst goes out of scope here.  */
125   VA_CLOSE (args);
126 
127   return save_dst;
128 }
129 
130 #ifdef __cplusplus
131 extern "C" {
132 #endif /* __cplusplus */
133 char *libiberty_concat_ptr;
134 #ifdef __cplusplus
135 }
136 #endif /* __cplusplus */
137 
138 /* @undocumented concat_copy2 */
139 
140 char *
concat_copy2(const char * first,...)141 concat_copy2 (const char *first, ...)
142 {
143   VA_OPEN (args, first);
144   VA_FIXEDARG (args, const char *, first);
145   vconcat_copy (libiberty_concat_ptr, first, args);
146   VA_CLOSE (args);
147 
148   return libiberty_concat_ptr;
149 }
150 
151 char *
concat(const char * first,...)152 concat (const char *first, ...)
153 {
154   char *newstr;
155 
156   /* First compute the size of the result and get sufficient memory.  */
157   VA_OPEN (args, first);
158   VA_FIXEDARG (args, const char *, first);
159   newstr = XNEWVEC (char, vconcat_length (first, args) + 1);
160   VA_CLOSE (args);
161 
162   /* Now copy the individual pieces to the result string. */
163   VA_OPEN (args, first);
164   VA_FIXEDARG (args, const char *, first);
165   vconcat_copy (newstr, first, args);
166   VA_CLOSE (args);
167 
168   return newstr;
169 }
170 
171 /*
172 
173 @deftypefn Extension char* reconcat (char *@var{optr}, const char *@var{s1}, @dots{}, @code{NULL})
174 
175 Same as @code{concat}, except that if @var{optr} is not @code{NULL} it
176 is freed after the string is created.  This is intended to be useful
177 when you're extending an existing string or building up a string in a
178 loop:
179 
180 @example
181   str = reconcat (str, "pre-", str, NULL);
182 @end example
183 
184 @end deftypefn
185 
186 */
187 
188 char *
reconcat(char * optr,const char * first,...)189 reconcat (char *optr, const char *first, ...)
190 {
191   char *newstr;
192 
193   /* First compute the size of the result and get sufficient memory.  */
194   VA_OPEN (args, first);
195   VA_FIXEDARG (args, char *, optr);
196   VA_FIXEDARG (args, const char *, first);
197   newstr = XNEWVEC (char, vconcat_length (first, args) + 1);
198   VA_CLOSE (args);
199 
200   /* Now copy the individual pieces to the result string. */
201   VA_OPEN (args, first);
202   VA_FIXEDARG (args, char *, optr);
203   VA_FIXEDARG (args, const char *, first);
204   vconcat_copy (newstr, first, args);
205   if (optr) /* Done before VA_CLOSE so optr stays in scope for K&R C.  */
206     free (optr);
207   VA_CLOSE (args);
208 
209   return newstr;
210 }
211 
212 #ifdef MAIN
213 #define NULLP (char *)0
214 
215 /* Simple little test driver. */
216 
217 #include <stdio.h>
218 
219 int
main(void)220 main (void)
221 {
222   printf ("\"\" = \"%s\"\n", concat (NULLP));
223   printf ("\"a\" = \"%s\"\n", concat ("a", NULLP));
224   printf ("\"ab\" = \"%s\"\n", concat ("a", "b", NULLP));
225   printf ("\"abc\" = \"%s\"\n", concat ("a", "b", "c", NULLP));
226   printf ("\"abcd\" = \"%s\"\n", concat ("ab", "cd", NULLP));
227   printf ("\"abcde\" = \"%s\"\n", concat ("ab", "c", "de", NULLP));
228   printf ("\"abcdef\" = \"%s\"\n", concat ("", "a", "", "bcd", "ef", NULLP));
229   return 0;
230 }
231 
232 #endif
233