util/uri: URI member path can be null, compare more carfully
commitafb30dde3ad71349fc65726946d58e5d3c61f8af
authorMarkus Armbruster <armbru@redhat.com>
Tue, 27 Jan 2015 16:13:52 +0000 (27 17:13 +0100)
committerMichael Tokarev <mjt@tls.msk.ru>
Tue, 10 Feb 2015 06:27:20 +0000 (10 09:27 +0300)
tree4467ee905e89ff5fe7db42d9a230f9233e73191d
parentafd5ea3671f936f511015a71af9cd0ed23788515
util/uri: URI member path can be null, compare more carfully

uri_resolve_relative() calls strcmp(bas->path, ref->path).  However,
either argument could be null!  Evidence: the code checks for null
after the comparison.  Spotted by Coverity.

I suspect this was screwed up when we stole the code from libxml2.
There the conditional reads

    xmlStrEqual((xmlChar *)bas->path, (xmlChar *)ref->path)

with

    int
    xmlStrEqual(const xmlChar *str1, const xmlChar *str2) {
if (str1 == str2) return(1);
if (str1 == NULL) return(0);
if (str2 == NULL) return(0);
do {
    if (*str1++ != *str2) return(0);
} while (*str2++);
return(1);
    }

Fix by replicating libxml2's logic faithfully.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
util/uri.c