diff options
Diffstat (limited to 'string/argz-replace.c')
-rw-r--r-- | string/argz-replace.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/string/argz-replace.c b/string/argz-replace.c new file mode 100644 index 0000000..4d658f4 --- /dev/null +++ b/string/argz-replace.c @@ -0,0 +1,135 @@ +/* String replacement in an argz vector + Copyright (C) 1997 Free Software Foundation, Inc. + 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 Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <stdlib.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) + { + memcpy (new_to + *to_len, buf, buf_len); + new_to[new_len] = '\0'; + *to = new_to; + *to_len = new_len; + } + else + { + free (*to); + *to = 0; + } +} + +/* Replace any occurances 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) |