1 files changed, 86 insertions, 17 deletions

diff --git a/src/common.h b/src/common.h
index ca9e439..4ac8b53 100644
--- a/src/common.h
+++ b/src/common.h
@@ -82,6 +82,11 @@
 
 
 #if defined(__GNUC__)
+# pragma GCC diagnostic ignored "-Wunsuffixed-float-constants"
+#endif
+
+
+#if defined(__GNUC__)
 # define GCC_ONLY(...) __VA_ARGS__
 #else
 # define GCC_ONLY(...)
@@ -89,13 +94,7 @@
 
 
 /**
- * The colour temperature corresponding to no effect
- */
-#define NEUTRAL_TEMP  6500
-
-
-/**
- * Truncate a value into a bounded range
+ * Truncate a value into a closed range
  * 
  * @param   LO  The lower bound
  * @param   X   The value to truncated
@@ -104,6 +103,43 @@
  */
 #define CLAMP(LO, X, UP)  (((LO) > (X)) ? (LO) : (((X) < (UP)) ? (X) : (UP)))
 
+/**
+ * Check whether a value is within a closed range
+ *
+ * @param   LO    The lower bound
+ * @param   X     The value to check
+ * @param   UP    The upper bound
+ * @return  :int  1 if `X` is within [`LO`, `UP`], 0 otherwise
+ */
+#define WITHIN(LO, X, UP)  ((LO) <= (X) && (X) <= (UP))
+
+
+/**
+ * The colour temperature corresponding to no effect
+ */
+#define NEUTRAL_TEMP  6500U
+
+/**
+ * Initialiser for `struct color_setting`
+ * 
+ * Sets all values to their neutral values (no effects applied)
+ */
+#define COLOR_SETTING_NEUTRAL  ((struct color_setting){NEUTRAL_TEMP, 1.0, {1.0, 1.0, 1.0}})
+
+
+/**
+ * State of an adjustment method
+ * 
+ * Each method has their own definition of this structure
+ */
+typedef struct gamma_state GAMMA_STATE;
+
+/**
+ * State of a location provider
+ * 
+ * Each provider has their own definition of this structure
+ */
+typedef struct location_state LOCATION_STATE;
 
 
 enum period {
@@ -121,16 +157,45 @@ enum program_mode {
 	PROGRAM_MODE_MANUAL
 };
 
+
+/**
+ * Geographical location, using GPS coordinates
+ */
 struct location {
-	double lat, lon;
+	/**
+	 * Degrees north of the equator
+	 */
+	double lat;
+
+	/**
+	 * Degrees east of the prime meridian
+	 */
+	double lon;
 };
 
+
+/**
+ * Colour setting to apply
+ */
 struct color_setting {
-	int temperature;
-	double gamma[3];
+	/**
+	 * Colour temperature, in Kelvin
+	 */
+	unsigned long int temperature;
+
+	/**
+	 * Whitepoint brightness level
+	 */
 	double brightness;
+
+	/**
+	 * Gamma correct, for the each RGB channel
+	 * in the order: red, green, and blue
+	 */
+	double gamma[3];
 };
 
+
 /* Time range.
    Fields are offsets from midnight in seconds. */
 struct time_range {
@@ -138,6 +203,7 @@ struct time_range {
 	int end;
 };
 
+
 /* Transition scheme.
    The solar elevations at which the transition begins/ends,
    and the association color settings. */
@@ -151,18 +217,21 @@ struct transition_scheme {
 	struct color_setting night;
 };
 
+
 struct config_ini_setting {
 	struct config_ini_setting *next;
 	char *name;
 	char *value;
 };
 
+
 struct config_ini_section {
 	struct config_ini_section *next;
 	char *name;
 	struct config_ini_setting *settings;
 };
 
+
 struct config_ini_state {
 	struct config_ini_section *sections;
 };
@@ -177,7 +246,7 @@ struct options {
 	int verbose;
 
 	/* Temperature to set in manual mode. */
-	int temp_set;
+	unsigned long int temp_set;
 	/* Whether to fade between large skips in color temperature. */
 	int use_fade;
 	/* Whether to preserve gamma ramps if supported by gamma method. */
@@ -195,9 +264,9 @@ struct options {
 };
 
 
-/* Gamma adjustment method */
-typedef struct gamma_state GAMMA_STATE;
-
+/**
+ * Adjustment method information and interface
+ */
 struct gamma_method {
 	const char *name;
 
@@ -223,9 +292,9 @@ struct gamma_method {
 };
 
 
-/* Location provider */
-typedef struct location_state LOCATION_STATE;
-
+/**
+ * Location provider information and interface
+ */
 struct location_provider {
 	const char *name;