xenstore: xenbus cannot be opened read-only

In order to read keys from xenstore, the xenstore libraries need to
write the request to the xenbus socket. This means that the socket
cannot be opened read-only.

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/xenstore/xs.c b/tools/xenstore/xs.c
index c72ea83d96c479aa032c8df2114019e1ff6baed9..df270f7dd240903b247142049a6ee05dedd141bf 100644 (file)
--- a/tools/xenstore/xs.c
+++ b/tools/xenstore/xs.c
@@ -182,15 +182,13 @@ error:
        return -1;
 }
 
-static int get_dev(const char *connect_to, unsigned long flags)
+static int get_dev(const char *connect_to)
 {
-       if (flags & XS_OPEN_READONLY)
-               return open(connect_to, O_RDONLY);
-       else
-               return open(connect_to, O_RDWR);
+       /* We cannot open read-only because requests are writes */
+       return open(connect_to, O_RDWR);
 }
 
-static struct xs_handle *get_handle(const char *connect_to, unsigned long flags)
+static struct xs_handle *get_handle(const char *connect_to)
 {
        struct stat buf;
        struct xs_handle *h = NULL;
@@ -202,7 +200,7 @@ static struct xs_handle *get_handle(const char *connect_to, unsigned long flags)
        if (S_ISSOCK(buf.st_mode))
                fd = get_socket(connect_to);
        else
-               fd = get_dev(connect_to, flags);
+               fd = get_dev(connect_to);
 
        if (fd == -1)
                return NULL;
@@ -258,12 +256,12 @@ struct xs_handle *xs_open(unsigned long flags)
        struct xs_handle *xsh = NULL;
 
        if (flags & XS_OPEN_READONLY)
-               xsh = get_handle(xs_daemon_socket_ro(), flags);
+               xsh = get_handle(xs_daemon_socket_ro());
        else
-               xsh = get_handle(xs_daemon_socket(), flags);
+               xsh = get_handle(xs_daemon_socket());
 
        if (!xsh && !(flags & XS_OPEN_SOCKETONLY))
-               xsh = get_handle(xs_domain_dev(), flags);
+               xsh = get_handle(xs_domain_dev());
 
        return xsh;
 }