2 * collectd - src/utils_subst.c
3 * Copyright (C) 2008 Sebastian Harl
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24 * Sebastian "tokkee" Harl <sh at tokkee.org>
28 * This module provides functions for string substitution.
34 #include "utils_subst.h"
36 char *subst(char *buf, size_t buflen, const char *string, size_t off1,
37 size_t off2, const char *replacement) {
43 size_t replacement_len;
46 if ((NULL == buf) || (0 == buflen) || (NULL == string) ||
47 (NULL == replacement))
50 size_t string_len = strlen(string);
51 if ((off1 > string_len) || (off2 > string_len) || (off1 > off2))
57 replacement_len = strlen(replacement);
58 back_len = strlen(back);
60 if (front_len >= buflen) {
61 front_len = buflen - 1;
64 } else if ((front_len + replacement_len) >= buflen) {
65 replacement_len = buflen - (front_len + 1);
67 } else if ((front_len + replacement_len + back_len) >= buflen) {
68 back_len = buflen - (front_len + replacement_len + 1);
70 buflen = front_len + replacement_len + back_len + 1;
72 assert((front_len + replacement_len + back_len) == (buflen - 1));
75 sstrncpy(out, front, front_len + 1);
79 if (replacement_len != 0) {
80 sstrncpy(out, replacement, replacement_len + 1);
81 out += replacement_len;
85 sstrncpy(out, back, back_len + 1);
93 char *asubst(const char *string, int off1, int off2, const char *replacement) {
99 if ((NULL == string) || (0 > off1) || (0 > off2) || (off1 > off2) ||
100 (NULL == replacement))
103 len = off1 + strlen(replacement) + strlen(string) - off2 + 1;
109 ret = subst(buf, len, string, off1, off2, replacement);
115 char *subst_string(char *buf, size_t buflen, const char *string,
116 const char *needle, const char *replacement) {
120 if ((buf == NULL) || (string == NULL) || (needle == NULL) ||
121 (replacement == NULL))
124 needle_len = strlen(needle);
125 sstrncpy(buf, string, buflen);
127 /* Limit the loop to prevent endless loops. */
128 for (i = 0; i < buflen; i++) {
133 /* Find `needle' in `buf'. */
134 begin_ptr = strstr(buf, needle);
135 if (begin_ptr == NULL)
138 /* Calculate the start offset. */
139 begin = begin_ptr - buf;
141 /* Substitute the region using `subst'. The result is stored in
144 subst(temp, buflen, buf, begin, begin + needle_len, replacement);
145 if (begin_ptr == NULL) {
146 WARNING("subst_string: subst failed.");
150 /* Copy the new string in `temp' to `buf' for the next round. */
151 strncpy(buf, temp, buflen);
155 WARNING("subst_string: Loop exited after %zu iterations: "
156 "string = %s; needle = %s; replacement = %s;",
157 i, string, needle, replacement);
161 } /* char *subst_string */