Implement strmem() and use it in join(1)

We want our delimiters to also contain 0 characters and have them
handled gracefully.
To accomplish this, I wrote a function strmem(), which looks for a
certain, arbitrarily long memory subset in a given string.
memmem() is a GNU extension and forces you to call strlen every time.
This commit is contained in:
FRIGN 2016-02-25 21:44:46 +01:00 committed by sin
parent e8eeb19fcd
commit 3396088666
4 changed files with 27 additions and 1 deletions

View File

@ -75,6 +75,7 @@ LIBUTILSRC =\
libutil/strcasestr.c\ libutil/strcasestr.c\
libutil/strlcat.c\ libutil/strlcat.c\
libutil/strlcpy.c\ libutil/strlcpy.c\
libutil/strmem.c\
libutil/strsep.c\ libutil/strsep.c\
libutil/strtonum.c\ libutil/strtonum.c\
libutil/unescape.c libutil/unescape.c

2
join.c
View File

@ -225,7 +225,7 @@ makeline(char *s, size_t len)
beg = sp; beg = sp;
if (sep) { if (sep) {
if (!(end = utfutf(sp, sep))) if (!(end = strmem(sp, sep, seplen)))
eol = 1; eol = 1;
if (!eol) { if (!eol) {

23
libutil/strmem.c Normal file
View File

@ -0,0 +1,23 @@
/* See LICENSE file for copyright and license details. */
#include <stddef.h>
#include <string.h>
char *
strmem(char *haystack, char *needle, size_t needlelen)
{
size_t i;
for (i = 0; i < needlelen; i++) {
if (haystack[i] == '\0') {
return NULL;
}
}
for (; haystack[i]; i++) {
if (!(memcmp(haystack + i - needlelen, needle, needlelen))) {
return (haystack + i - needlelen);
}
}
return NULL;
}

2
util.h
View File

@ -58,6 +58,8 @@ size_t estrlcpy(char *, const char *, size_t);
#undef strsep #undef strsep
char *strsep(char **, const char *); char *strsep(char **, const char *);
char *strmem(char *, char *, size_t);
/* regex */ /* regex */
int enregcomp(int, regex_t *, const char *, int); int enregcomp(int, regex_t *, const char *, int);
int eregcomp(regex_t *, const char *, int); int eregcomp(regex_t *, const char *, int);