1 files changed, 65 insertions, 0 deletions
diff --git a/lib/support/devname.c b/lib/support/devname.c
new file mode 100644
index 0000000..e0306dd
--- /dev/null
+++ b/lib/support/devname.c
@@ -0,0 +1,65 @@
+/*
+ * devname.c --- Support function to translate a user provided string
+ * identifying a device to an actual device path
+ *
+ * Copyright (C) 2022 Red Hat, Inc., Lukas Czerner <lczerner@redhat.com>
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "config.h"
+#include "devname.h"
+#include "nls-enable.h"
+
+/*
+ *  blkid_get_devname() is primarily intended for parsing "NAME=value"
+ *  tokens. It will return the device matching the specified token, NULL if
+ *  nothing is found, or copy of the string if it's not in "NAME=value"
+ *  format.
+ *  get_devname() takes the same parameters and works the same way as
+ *  blkid_get_devname() except it can handle '=' in the file name.
+ */
+char *get_devname(blkid_cache cache, const char *token, const char *value)
+{
+	int is_file = 0;
+	char *ret = NULL;
+
+	if (!token)
+		goto out;
+
+	if (value) {
+		ret = blkid_get_devname(cache, token, value);
+		goto out;
+	}
+
+	if (access(token, F_OK) == 0)
+		is_file = 1;
+
+	ret = blkid_get_devname(cache, token, NULL);
+	if (ret) {
+		/*
+		 * In case of collision prefer the result from
+		 * blkid_get_devname() to avoid a file masking file system with
+		 * existing tag.
+		 */
+		if (is_file && (strcmp(ret, token) != 0)) {
+			fprintf(stderr,
+				_("Collision found: '%s' refers to both '%s' "
+				  "and a file '%s'. Using '%s'!\n"),
+				token, ret, token, ret);
+		}
+		goto out;
+	}
+
+	if (is_file)
+		ret = strdup(token);
+out:
+	return ret;
+}