1 files changed, 44 insertions, 0 deletions
diff --git a/libgamma_group_name.c b/libgamma_group_name.c
new file mode 100644
index 0000000..ce59300
--- /dev/null
+++ b/libgamma_group_name.c
@@ -0,0 +1,44 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+static _Thread_local char group_name[64]; /* Group names can only be up to 16 bytes logn, 63 is a very safe number */
+
+
+/**
+ * Get the group that the user needs to be a member of
+ * if `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned
+ * 
+ * @return  The group that the user needs to be a member of if
+ *          `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned, `NULL`
+ *          if the name of the group `libgamma_group_gid` cannot
+ *          be determined
+ */
+const char *
+libgamma_group_name_get(void)
+{
+	return *group_name ? group_name : NULL;
+}
+
+
+/**
+ * Set the group that the user needs to be a member of
+ * if `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned
+ * 
+ * @param  value  The group that the user needs to be a member of if
+ *                `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned, may be `NULL`
+ */
+void
+libgamma_group_name_set(const char *value)
+{
+	size_t n;
+	if (!value) {
+		*group_name = 0;
+	} else {
+		n = strlen(value);
+		if (n >= sizeof(group_name))
+			*group_name = 0;
+		else
+			memcpy(group_name, value, n + 1);
+	}
+}