[PATCH] Fix regex matching for OS media

["Daniel P. Berrange" <berrange@xxxxxxxxxx>]

From: "Daniel P. Berrange" <berrange@xxxxxxxxxx>

The current regex match rule is

   If pattern is NULL and string is NULL
      -> accept media
   else if pattern is NULL or string is NULL
      -> reject media
   else
      -> do regex compare

The regex match rules ought to be

   If pattern is NULL
       -> accept media
   Else if string is NULL
       -> reject media
   else
       -> do regex compare

The idea is that if the Osinfo database pattern is NULL, then
regardless of whether the string is NULL or not, then we should
allow that match. In effect a pattern == NULL, should be treated
as equivalent to a regex ".*"
---
 osinfo/osinfo_db.c |   16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/osinfo/osinfo_db.c b/osinfo/osinfo_db.c
index ecc8fbd..52c7868 100644
--- a/osinfo/osinfo_db.c
+++ b/osinfo/osinfo_db.c
@@ -30,9 +30,10 @@ G_DEFINE_TYPE (OsinfoDb, osinfo_db, G_TYPE_OBJECT);
 
 #define OSINFO_DB_GET_PRIVATE(obj) (G_TYPE_INSTANCE_GET_PRIVATE ((obj), OSINFO_TYPE_DB, OsinfoDbPrivate))
 
-#define match_regex(pattern, str) (((pattern) == NULL && (str) == NULL) || \
-                                   ((pattern) != NULL && (str) != NULL && \
-                                    g_regex_match_simple((pattern), (str), 0, 0)))
+#define match_regex(pattern, str)                                       \
+    (((pattern) == NULL) ||                                             \
+     (((str) != NULL) &&                                                \
+      g_regex_match_simple((pattern), (str), 0, 0)))
 
 /**
  * SECTION:osinfo_db
@@ -386,11 +387,10 @@ OsinfoOs *osinfo_db_guess_os_from_media(OsinfoDb *db,
             const gchar *os_publisher = osinfo_media_get_publisher_id(os_media);
             const gchar *os_application = osinfo_media_get_application_id(os_media);
 
-            if ((match_regex (os_volume, media_volume) ||
-                 match_regex (os_application, media_application))
-                 &&
-                (match_regex (os_system, media_system) ||
-                 match_regex (os_publisher, media_publisher))) {
+            if (match_regex (os_volume, media_volume) &&
+                match_regex (os_application, media_application) &&
+                match_regex (os_system, media_system) &&
+                match_regex (os_publisher, media_publisher)) {
                 ret = os;
                 if (matched_media != NULL)
                     *matched_media = os_media;
-- 
1.7.7.6