1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
/*
* Copyright (c) 2002 J. Mallett. All rights reserved.
* You may do whatever you want with this file as long as
* the above copyright and this notice remain intact, along
* with the following statement:
* For the man who taught me vi, and who got too old, too young.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../util.h"
/*
* Replaces str with a string consisting of str with match replaced with
* replstr as many times as can be done before the constructed string is
* maxsize bytes large. It does not free the string pointed to by str, it
* is up to the calling program to be sure that the original contents of
* str as well as the new contents are handled in an appropriate manner.
* If replstr is NULL, then that internally is changed to a nil-string, so
* that we can still pretend to do somewhat meaningful substitution.
* No value is returned.
*/
void
strnsubst(char **str, const char *match, const char *replstr, size_t maxsize)
{
char *s1, *s2, *this;
size_t matchlen, s2len;
int n;
if ((s1 = *str) == NULL)
return;
s2 = emalloc(maxsize);
if (replstr == NULL)
replstr = "";
if (match == NULL || *match == '\0' || strlen(s1) >= maxsize) {
strlcpy(s2, s1, maxsize);
goto done;
}
*s2 = '\0';
s2len = 0;
matchlen = strlen(match);
for (;;) {
if ((this = strstr(s1, match)) == NULL)
break;
n = snprintf(s2 + s2len, maxsize - s2len, "%.*s%s",
(int)(this - s1), s1, replstr);
if (n == -1 || n + s2len + strlen(this + matchlen) >= maxsize)
break; /* out of room */
s2len += n;
s1 = this + matchlen;
}
strlcpy(s2 + s2len, s1, maxsize - s2len);
done:
*str = s2;
return;
}
|
