glibc/string/argz-replace.c
Jakub Jelinek 0ecb606cb6 2.5-18.1
2007-07-12 18:26:36 +00:00

137 lines
3.6 KiB
C

/* String replacement in an argz vector
Copyright (C) 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by Miles Bader <miles@gnu.ai.mit.edu>
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <stdlib.h>
#include <string.h>
#include <argz.h>
/* Append BUF, of length BUF_LEN to *TO, of length *TO_LEN, reallocating and
updating *TO & *TO_LEN appropriately. If an allocation error occurs,
*TO's old value is freed, and *TO is set to 0. */
static void
str_append (char **to, size_t *to_len, const char *buf, const size_t buf_len)
{
size_t new_len = *to_len + buf_len;
char *new_to = realloc (*to, new_len + 1);
if (new_to)
{
*((char *) __mempcpy (new_to + *to_len, buf, buf_len)) = '\0';
*to = new_to;
*to_len = new_len;
}
else
{
free (*to);
*to = 0;
}
}
/* Replace any occurrences of the string STR in ARGZ with WITH, reallocating
ARGZ as necessary. If REPLACE_COUNT is non-zero, *REPLACE_COUNT will be
incremented by number of replacements performed. */
error_t
__argz_replace (char **argz, size_t *argz_len, const char *str, const char *with,
unsigned *replace_count)
{
error_t err = 0;
if (str && *str)
{
char *arg = 0;
char *src = *argz;
size_t src_len = *argz_len;
char *dst = 0;
size_t dst_len = 0;
int delayed_copy = 1; /* True while we've avoided copying anything. */
size_t str_len = strlen (str), with_len = strlen (with);
while (!err && (arg = argz_next (src, src_len, arg)))
{
char *match = strstr (arg, str);
if (match)
{
char *from = match + str_len;
size_t to_len = match - arg;
char *to = __strndup (arg, to_len);
while (to && from)
{
str_append (&to, &to_len, with, with_len);
if (to)
{
match = strstr (from, str);
if (match)
{
str_append (&to, &to_len, from, match - from);
from = match + str_len;
}
else
{
str_append (&to, &to_len, from, strlen (from));
from = 0;
}
}
}
if (to)
{
if (delayed_copy)
/* We avoided copying SRC to DST until we found a match;
now that we've done so, copy everything from the start
of SRC. */
{
if (arg > src)
err = __argz_append (&dst, &dst_len, src, (arg - src));
delayed_copy = 0;
}
if (! err)
err = __argz_add (&dst, &dst_len, to);
free (to);
}
else
err = ENOMEM;
if (replace_count)
(*replace_count)++;
}
else if (! delayed_copy)
err = __argz_add (&dst, &dst_len, arg);
}
if (! err)
{
if (! delayed_copy)
/* We never found any instances of str. */
{
if (src)
free (src);
*argz = dst;
*argz_len = dst_len;
}
}
else if (dst_len > 0)
free (dst);
}
return err;
}
weak_alias (__argz_replace, argz_replace)