From: Jeremiah Mahler Date: Tue, 17 Jun 2014 15:49:26 GMT Subject: Re: [PATCH v2 1/3] add strnncmp() function Message-ID: <20140617154926.GB5162@hudson.localdomain> In-Reply-To: Erik, On Tue, Jun 17, 2014 at 11:09:59AM +0200, Erik Faye-Lund wrote: > On Tue, Jun 17, 2014 at 9:34 AM, Jeremiah Mahler wrote: > > Add a strnncmp() function which behaves like strncmp() except it takes > > the length of both strings instead of just one. It behaves the same as > > strncmp() up to the minimum common length between the strings. When the > > strings are identical up to this minimum common length, the length > > difference is returned. > > > > Signed-off-by: Jeremiah Mahler > > --- > > strbuf.c | 9 +++++++++ > > strbuf.h | 2 ++ > > 2 files changed, 11 insertions(+) > > > > diff --git a/strbuf.c b/strbuf.c > > index ac62982..4eb7954 100644 > > --- a/strbuf.c > > +++ b/strbuf.c > > @@ -600,3 +600,12 @@ char *xstrdup_tolower(const char *string) > > result[i] = '\0'; > > return result; > > } > > + > > +int strnncmp(const char *a, int len_a, const char *b, int len_b) > > +{ > > + int min_len = (len_a < len_b) ? len_a : len_b; > > + int cmp = strncmp(a, b, min_len); > > + if (cmp) > > + return cmp; > > + return (len_a - len_b); > > +} > > Using a name that sounds like it's from the stdlib makes me cringe a > little bit. Names that start with "str" reserved for stdlib[1][2], but > we already ignore this for strbuf (and perhaps some other functions). > However, in this case it doesn't seem *that* unlikely that we might > collide with some stdlib-extensions. > > [1]: http://pubs.opengroup.org/onlinepubs/007904975/functions/xsh_chap02_02.html#tag_02_02_02 > [2]: http://www.gnu.org/software/libc/manual/html_node/Reserved-Names.html I chose strnncmp() to try and emphasize its similarity to strncmp(). But you have a good point about potential name conflicts. That could be a problem. I will change the name. -- Jeremiah Mahler jmmahler@gmail.com http://github.com/jmahler