Update.
[glibc.git] / string / argz-replace.c
blobcc1807689b7edc934a233f3541387378395a194e
1 /* String replacement in an argz vector
2 Copyright (C) 1997, 1998 Free Software Foundation, Inc.
3 Written by Miles Bader <miles@gnu.ai.mit.edu>
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
20 #include <stdlib.h>
21 #include <string.h>
22 #include <argz.h>
24 /* Append BUF, of length BUF_LEN to *TO, of length *TO_LEN, reallocating and
25 updating *TO & *TO_LEN appropriately. If an allocation error occurs,
26 *TO's old value is freed, and *TO is set to 0. */
27 static void
28 str_append (char **to, size_t *to_len, const char *buf, const size_t buf_len)
30 size_t new_len = *to_len + buf_len;
31 char *new_to = realloc (*to, new_len + 1);
33 if (new_to)
35 *((char *) __mempcpy (new_to + *to_len, buf, buf_len)) = '\0';
36 *to = new_to;
37 *to_len = new_len;
39 else
41 free (*to);
42 *to = 0;
46 /* Replace any occurrences of the string STR in ARGZ with WITH, reallocating
47 ARGZ as necessary. If REPLACE_COUNT is non-zero, *REPLACE_COUNT will be
48 incremented by number of replacements performed. */
49 error_t
50 __argz_replace (char **argz, size_t *argz_len, const char *str, const char *with,
51 unsigned *replace_count)
53 error_t err = 0;
55 if (str && *str)
57 char *arg = 0;
58 char *src = *argz;
59 size_t src_len = *argz_len;
60 char *dst = 0;
61 size_t dst_len = 0;
62 int delayed_copy = 1; /* True while we've avoided copying anything. */
63 size_t str_len = strlen (str), with_len = strlen (with);
65 while (!err && (arg = argz_next (src, src_len, arg)))
67 char *match = strstr (arg, str);
68 if (match)
70 char *from = match + str_len;
71 size_t to_len = match - arg;
72 char *to = __strndup (arg, to_len);
74 while (to && from)
76 str_append (&to, &to_len, with, with_len);
77 if (to)
79 match = strstr (from, str);
80 if (match)
82 str_append (&to, &to_len, from, match - from);
83 from = match + str_len;
85 else
87 str_append (&to, &to_len, from, strlen (from));
88 from = 0;
93 if (to)
95 if (delayed_copy)
96 /* We avoided copying SRC to DST until we found a match;
97 now that we've done so, copy everything from the start
98 of SRC. */
100 if (arg > src)
101 err = __argz_append (&dst, &dst_len, src, (arg - src));
102 delayed_copy = 0;
104 if (! err)
105 err = __argz_add (&dst, &dst_len, to);
106 free (to);
108 else
109 err = ENOMEM;
111 if (replace_count)
112 (*replace_count)++;
114 else if (! delayed_copy)
115 err = __argz_add (&dst, &dst_len, arg);
118 if (! err)
120 if (! delayed_copy)
121 /* We never found any instances of str. */
123 if (src)
124 free (src);
125 *argz = dst;
126 *argz_len = dst_len;
129 else if (dst_len > 0)
130 free (dst);
133 return err;
135 weak_alias (__argz_replace, argz_replace)