osinfo: pull media matching logic into public API

The logic for matching an unidentified media against a reference media
is potentially useful to applications and should be part of a public
API, rather than hidden.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

5 files changed, 150 insertions, 31 deletions

diff --git a/osinfo/libosinfo.syms b/osinfo/libosinfo.syms
index a561788..724ea15 100644
--- a/osinfo/libosinfo.syms
+++ b/osinfo/libosinfo.syms
@@ -639,6 +639,7 @@ LIBOSINFO_1.8.0 {
 LIBOSINFO_1.10.0 {
 	global:
 
+	osinfo_media_matches;
 	osinfo_os_get_complete_firmware_list;
 } LIBOSINFO_1.8.0;
 
diff --git a/osinfo/osinfo_db.c b/osinfo/osinfo_db.c
index 5b60fc5..4002915 100644
--- a/osinfo/osinfo_db.c
+++ b/osinfo/osinfo_db.c
@@ -552,17 +552,6 @@ static gboolean compare_media(OsinfoMedia *media,
                               GList **fallback_oss)
 {
     GList *os_iter;
-    const gchar *media_volume;
-    const gchar *media_system;
-    const gchar *media_publisher;
-    const gchar *media_application;
-    gint64 media_vol_size;
-
-    media_volume = osinfo_media_get_volume_id(media);
-    media_system = osinfo_media_get_system_id(media);
-    media_publisher = osinfo_media_get_publisher_id(media);
-    media_application = osinfo_media_get_application_id(media);
-    media_vol_size = osinfo_media_get_volume_size(media);
 
     for (os_iter = oss; os_iter; os_iter = os_iter->next) {
         OsinfoOs *os = OSINFO_OS(os_iter->data);
@@ -576,18 +565,6 @@ static gboolean compare_media(OsinfoMedia *media,
         for (media_iter = medias; media_iter; media_iter = media_iter->next) {
             OsinfoMedia *os_media = OSINFO_MEDIA(media_iter->data);
             const gchar *os_arch = osinfo_media_get_architecture(os_media);
-            const gchar *os_volume = osinfo_media_get_volume_id(os_media);
-            const gchar *os_system = osinfo_media_get_system_id(os_media);
-            const gchar *os_publisher = osinfo_media_get_publisher_id(os_media);
-            const gchar *os_application = osinfo_media_get_application_id(os_media);
-            gint64 os_vol_size = osinfo_media_get_volume_size(os_media);
-
-            if (os_volume == NULL &&
-                os_system == NULL &&
-                os_publisher == NULL &&
-                os_application == NULL &&
-                os_vol_size <= 0)
-                continue;
 
             if (fallback_oss != NULL) {
                 if (g_str_equal(os_arch, "all")) {
@@ -601,14 +578,7 @@ static gboolean compare_media(OsinfoMedia *media,
                 }
             }
 
-            if (os_vol_size <= 0)
-                os_vol_size = media_vol_size;
-
-            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) &&
-                os_vol_size == media_vol_size) {
+            if (osinfo_media_matches(media, os_media)) {
                 *ret_os = os;
                 if (matched != NULL)
                     *matched = os_media;
diff --git a/osinfo/osinfo_media.c b/osinfo/osinfo_media.c
index cb859a3..87c91a4 100644
--- a/osinfo/osinfo_media.c
+++ b/osinfo/osinfo_media.c
@@ -1857,3 +1857,57 @@ gboolean osinfo_media_is_bootable(OsinfoMedia *media)
     return osinfo_entity_get_param_value_boolean(OSINFO_ENTITY(media),
                                                  OSINFO_MEDIA_PROP_BOOTABLE);
 }
+
+#define match_regex(pattern, str)                                       \
+    (((pattern) == NULL) ||                                             \
+     (((str) != NULL) &&                                                \
+      g_regex_match_simple((pattern), (str), 0, 0)))
+
+/**
+ * osinfo_media_matches:
+ * @media: an unidentified #OsinfoMedia instance
+ * @reference: a reference #OsinfoMedia instance
+ *
+ * Determines whether the metadata for the unidentified @media is a match
+ * for the @reference media.
+ *
+ * The metadata in the unidentified @media must be literal strings,
+ * while the metadata in the @reference media must be regular expressions.
+ *
+ * Returns: #TRUE if @media is a match for @reference. #FALSE otherwise
+ *
+ * Since: 1.10.0
+ */
+gboolean osinfo_media_matches(OsinfoMedia *media, OsinfoMedia *reference)
+{
+    const gchar *media_volume = osinfo_media_get_volume_id(media);
+    const gchar *media_system = osinfo_media_get_system_id(media);
+    const gchar *media_publisher = osinfo_media_get_publisher_id(media);
+    const gchar *media_application = osinfo_media_get_application_id(media);
+    gint64 media_vol_size = osinfo_media_get_volume_size(media);
+
+    const gchar *reference_volume = osinfo_media_get_volume_id(reference);
+    const gchar *reference_system = osinfo_media_get_system_id(reference);
+    const gchar *reference_publisher = osinfo_media_get_publisher_id(reference);
+    const gchar *reference_application = osinfo_media_get_application_id(reference);
+    gint64 reference_vol_size = osinfo_media_get_volume_size(reference);
+
+    if (reference_volume == NULL &&
+        reference_system == NULL &&
+        reference_publisher == NULL &&
+        reference_application == NULL &&
+        reference_vol_size <= 0)
+        return FALSE;
+
+    if (reference_vol_size <= 0)
+        reference_vol_size = media_vol_size;
+
+    if (match_regex(reference_volume, media_volume) &&
+        match_regex(reference_application, media_application) &&
+        match_regex(reference_system, media_system) &&
+        match_regex(reference_publisher, media_publisher) &&
+        reference_vol_size == media_vol_size)
+        return TRUE;
+
+    return FALSE;
+}
diff --git a/osinfo/osinfo_media.h b/osinfo/osinfo_media.h
index f0369de..e20e248 100644
--- a/osinfo/osinfo_media.h
+++ b/osinfo/osinfo_media.h
@@ -138,3 +138,4 @@ gboolean osinfo_media_get_eject_after_install(OsinfoMedia *media);
 gboolean osinfo_media_supports_installer_script(OsinfoMedia *media);
 void osinfo_media_add_install_script(OsinfoMedia *media, OsinfoInstallScript *script);
 OsinfoInstallScriptList *osinfo_media_get_install_script_list(OsinfoMedia *media);
+gboolean osinfo_media_matches(OsinfoMedia *media, OsinfoMedia *reference);
diff --git a/tests/test-media.c b/tests/test-media.c
index 0dc3d55..53a6124 100644
--- a/tests/test-media.c
+++ b/tests/test-media.c
@@ -139,6 +139,98 @@ test_loaded_installer_script(void)
     g_object_unref(loader);
 }
 
+static OsinfoMedia *
+test_create_media(const char *id,
+                  const char *arch,
+                  const char *volume,
+                  const char *system,
+                  const char *publisher,
+                  const char *application,
+                  guint64 size)
+{
+    OsinfoMedia *media = osinfo_media_new(id, arch);
+
+    if (volume)
+        osinfo_entity_set_param(OSINFO_ENTITY(media),
+                                OSINFO_MEDIA_PROP_VOLUME_ID,
+                                volume);
+    if (system)
+        osinfo_entity_set_param(OSINFO_ENTITY(media),
+                                OSINFO_MEDIA_PROP_SYSTEM_ID,
+                                system);
+    if (publisher)
+        osinfo_entity_set_param(OSINFO_ENTITY(media),
+                                OSINFO_MEDIA_PROP_PUBLISHER_ID,
+                                publisher);
+    if (application)
+        osinfo_entity_set_param(OSINFO_ENTITY(media),
+                                OSINFO_MEDIA_PROP_APPLICATION_ID,
+                                application);
+    if (size != 0)
+        osinfo_entity_set_param_int64(OSINFO_ENTITY(media),
+                                      OSINFO_MEDIA_PROP_VOLUME_SIZE,
+                                      size);
+
+    return media;
+}
+
+static void
+test_matching(void)
+{
+    OsinfoMedia *unknown = test_create_media("https://libosinfo.org/test/",
+                                             "x86_64",
+                                             "Fedora 35",
+                                             "LINUX",
+                                             "Fedora",
+                                             "Fedora OS",
+                                             1234567);
+    /* Match with several optional fields */
+    OsinfoMedia *reference1 = test_create_media("https://fedoraproject.org/fedora/35/media1",
+                                                "x86_64",
+                                                "Fedora 35",
+                                                NULL,
+                                                NULL,
+                                                NULL,
+                                                0);
+    /* Mis-match on volume */
+    OsinfoMedia *reference2 = test_create_media("https://fedoraproject.org/fedora/34/media2",
+                                                "x86_64",
+                                                "Fedora 34",
+                                                "LINUX",
+                                                NULL,
+                                                NULL,
+                                                0);
+    /* Match with all fields with some regexes */
+    OsinfoMedia *reference3 = test_create_media("https://fedoraproject.org/fedora/unknown/media3",
+                                                "x86_64",
+                                                "Fedora [0-9]+",
+                                                "LINUX",
+                                                "Fedora",
+                                                "Fedora OS",
+                                                0);
+    /* Match including vol size */
+    OsinfoMedia *reference4 = test_create_media("https://fedoraproject.org/fedora/35/media4",
+                                                "x86_64",
+                                                "Fedora 35",
+                                                "LINUX",
+                                                NULL,
+                                                NULL,
+                                                1234567);
+    /* Mis-match on vol size */
+    OsinfoMedia *reference5 = test_create_media("https://fedoraproject.org/fedora/35/media5",
+                                                "x86_64",
+                                                "Fedora 35",
+                                                "LINUX",
+                                                NULL,
+                                                NULL,
+                                                1234568);
+    g_assert(osinfo_media_matches(unknown, reference1));
+    g_assert(!osinfo_media_matches(unknown, reference2));
+    g_assert(osinfo_media_matches(unknown, reference3));
+    g_assert(osinfo_media_matches(unknown, reference4));
+    g_assert(!osinfo_media_matches(unknown, reference5));
+}
+
 int
 main(int argc, char *argv[])
 {
@@ -148,6 +240,7 @@ main(int argc, char *argv[])
     g_test_add_func("/media/loaded/attributes", test_loaded_attributes);
     g_test_add_func("/media/loaded/no-installer", test_loaded_no_installer);
     g_test_add_func("/media/loaded/installer-script", test_loaded_installer_script);
+    g_test_add_func("/media/matching", test_matching);
 
     /* Upfront so we don't confuse valgrind */
     osinfo_media_get_type();