1 files changed, 139 insertions, 0 deletions
diff --git a/src/libudev/libudev-hwdb.c b/src/libudev/libudev-hwdb.c
new file mode 100644
index 0000000000..1acffb86e9
--- /dev/null
+++ b/src/libudev/libudev-hwdb.c
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+/***
+  Copyright Tom Gundersen <teg@jklm.no>
+***/
+
+#include "sd-hwdb.h"
+
+#include "alloc-util.h"
+#include "hwdb-util.h"
+#include "libudev-private.h"
+
+/**
+ * SECTION:libudev-hwdb
+ * @short_description: retrieve properties from the hardware database
+ *
+ * Libudev hardware database interface.
+ */
+
+/**
+ * udev_hwdb:
+ *
+ * Opaque object representing the hardware database.
+ */
+struct udev_hwdb {
+        struct udev *udev;
+        int refcount;
+
+        sd_hwdb *hwdb;
+
+        struct udev_list properties_list;
+};
+
+/**
+ * udev_hwdb_new:
+ * @udev: udev library context
+ *
+ * Create a hardware database context to query properties for devices.
+ *
+ * Returns: a hwdb context.
+ **/
+_public_ struct udev_hwdb *udev_hwdb_new(struct udev *udev) {
+        _cleanup_(sd_hwdb_unrefp) sd_hwdb *hwdb_internal = NULL;
+        struct udev_hwdb *hwdb;
+        int r;
+
+        assert_return_errno(udev, NULL, EINVAL);
+
+        r = sd_hwdb_new(&hwdb_internal);
+        if (r < 0) {
+                errno = -r;
+                return NULL;
+        }
+
+        hwdb = new0(struct udev_hwdb, 1);
+        if (!hwdb) {
+                errno = ENOMEM;
+                return NULL;
+        }
+
+        hwdb->refcount = 1;
+        hwdb->hwdb = TAKE_PTR(hwdb_internal);
+
+        udev_list_init(udev, &hwdb->properties_list, true);
+
+        return hwdb;
+}
+
+/**
+ * udev_hwdb_ref:
+ * @hwdb: context
+ *
+ * Take a reference of a hwdb context.
+ *
+ * Returns: the passed enumeration context
+ **/
+_public_ struct udev_hwdb *udev_hwdb_ref(struct udev_hwdb *hwdb) {
+        if (!hwdb)
+                return NULL;
+        hwdb->refcount++;
+        return hwdb;
+}
+
+/**
+ * udev_hwdb_unref:
+ * @hwdb: context
+ *
+ * Drop a reference of a hwdb context. If the refcount reaches zero,
+ * all resources of the hwdb context will be released.
+ *
+ * Returns: #NULL
+ **/
+_public_ struct udev_hwdb *udev_hwdb_unref(struct udev_hwdb *hwdb) {
+        if (!hwdb)
+                return NULL;
+        hwdb->refcount--;
+        if (hwdb->refcount > 0)
+                return NULL;
+        sd_hwdb_unref(hwdb->hwdb);
+        udev_list_cleanup(&hwdb->properties_list);
+        return mfree(hwdb);
+}
+
+/**
+ * udev_hwdb_get_properties_list_entry:
+ * @hwdb: context
+ * @modalias: modalias string
+ * @flags: (unused)
+ *
+ * Lookup a matching device in the hardware database. The lookup key is a
+ * modalias string, whose formats are defined for the Linux kernel modules.
+ * Examples are: pci:v00008086d00001C2D*, usb:v04F2pB221*. The first entry
+ * of a list of retrieved properties is returned.
+ *
+ * Returns: a udev_list_entry.
+ */
+_public_ struct udev_list_entry *udev_hwdb_get_properties_list_entry(struct udev_hwdb *hwdb, const char *modalias, unsigned int flags) {
+        const char *key, *value;
+        struct udev_list_entry *e;
+
+        if (!hwdb || !modalias) {
+                errno = EINVAL;
+                return NULL;
+        }
+
+        udev_list_cleanup(&hwdb->properties_list);
+
+        SD_HWDB_FOREACH_PROPERTY(hwdb->hwdb, modalias, key, value) {
+                if (udev_list_entry_add(&hwdb->properties_list, key, value) == NULL) {
+                        errno = ENOMEM;
+                        return NULL;
+                }
+        }
+
+        e = udev_list_get_entry(&hwdb->properties_list);
+        if (!e)
+                errno = ENODATA;
+
+        return e;
+}