diff -r 0c1371488d87 -r c6a1ad6cf749 src/chess/rules.h
--- a/src/chess/rules.h	Fri Apr 04 17:36:42 2014 +0200
+++ b/src/chess/rules.h	Mon Apr 07 14:08:57 2014 +0200
@@ -145,20 +145,41 @@
 /**
  * Checks, if a specified field is covered by a piece of a certain color.
  * 
- * Note: when the field is covered by multiple pieces, this function returns
- * the first piece it can find.
+ * The out-parameters may both be NULL, but if any of them is set, the other
+ * must be set, too.
  * 
  * @param gamestate the current game state
  * @param row row of the field to check
  * @param file file of the field to check
  * @param color the color of the piece that should threaten the field
- * @param threat if not NULL: a pointer to the move structure where
- * the move that could be performed to capture the field should be stored
+ * @param threats the array where to store the threats (should be able to the
+ * rare maximum of 16 elements)
+ * @param threatcount a pointer to an uint8_t where to store the amount of threats
  * @return TRUE, if any piece of the specified color threatens the specified
  * field (i.e. could capture an opponent piece)
  */
-_Bool get_any_threat_for(GameState *gamestate, uint8_t row, uint8_t file,
-        uint8_t color, Move *threat);
+_Bool get_threats(GameState *gamestate, uint8_t row, uint8_t file,
+        uint8_t color, Move* threats, uint8_t* threatcount);
+
+/**
+ * Checks, if a specified field is covered by a piece of a certain color AND
+ * if this piece is not pinned and therefore able to perform the move.
+ * 
+ * The out-parameters may both be NULL, but if any of them is set, the other
+ * must be set, too.
+ * 
+ * @param gamestate the current game state
+ * @param row row of the field to check
+ * @param file file of the field to check
+ * @param color the color of the piece that should threaten the field
+ * @param threats the array where to store the threats (should be able to the
+ * rare maximum of 16 elements)
+ * @param threatcount a pointer to an uint8_t where to store the amount of threats
+ * @return TRUE, if any piece of the specified color threatens the specified
+ * field (i.e. could capture an opponent piece)
+ */
+_Bool get_real_threats(GameState *gamestate, uint8_t row, uint8_t file,
+        uint8_t color, Move* threats, uint8_t* threatcount);
 
 /**
  * Checks, if a specified field is covered by a piece of a certain color.
@@ -168,10 +189,42 @@
  * @param file file of the field to check
  * @param color the color of the piece that should cover the field
  * @return TRUE, if any piece of the specified color threatens the specified
- * field (i.e. could capture an opponent piece)
+ * field
  */
 #define is_covered(gamestate, row, file, color) \
-    get_any_threat_for(gamestate, row, file, color, NULL)
+    get_threats(gamestate, row, file, color, NULL, NULL)
+
+/**
+ * Checks, if a specified field is attacked by a piece of a certain color.
+ * 
+ * I.e. the field is covered by a piece AND this piece is not pinned and
+ * therefore able to perform the move.
+ * 
+ * @param gamestate the current game state
+ * @param row row of the field to check
+ * @param file file of the field to check
+ * @param color the color of the piece that should cover the field
+ * @return TRUE, if any piece of the specified color threatens the specified
+ * field and could capture an opponent piece
+ */
+#define is_attacked(gamestate, row, file, color) \
+    get_threats(gamestate, row, file, color, NULL, NULL)
+
+/**
+ * Checks, if a specified field is protected by a piece of a certain color.
+ * 
+ * I.e. the field is covered by a piece that is NOT the king AND this piece is
+ * not pinned and therefore able to perform the move.
+ * 
+ * @param gamestate the current game state
+ * @param row row of the field to check
+ * @param file file of the field to check
+ * @param color the color of the piece that should cover the field
+ * @return TRUE, if any piece (excluding the king) of the specified color
+ * threatens the specified field and could capture an opponent piece
+ */
+_Bool is_protected(GameState *gamestate, uint8_t row, uint8_t file,
+        uint8_t color);
 
 /**
  * Evaluates a move syntactically and stores the move data in the specified