cii: Add arith interface

cii/CMakeLists.txt

@@ -6,6 +6,7 @@ set(CMAKE_C_STANDARD 11)
 option(BUILD_TESTING "" ON)
 
 set(SOURCE_FILES
+    src/arith.c
     src/assert.c
     src/atom.c
     src/except.c
@@ -16,6 +17,7 @@ set(SOURCE_FILES
     src/table.c
     )
 set(HEADER_FILES
+    include/cii/arith.h
     include/cii/assert.h
     include/cii/atom.h
     include/cii/except.h

cii/include/cii/arith.h

@@ -0,0 +1,51 @@
+// Copyright (c) 2023 Xu Shaohua <[email protected]>. All rights reserved.
+// Use of this source is governed by GNU General Public License
+// that can be found in the LICENSE file.
+
+#ifndef CII_ARITH_H_
+#define CII_ARITH_H_
+
+/**
+ * Returns the maximum of two integers.
+ * @param x
+ * @param y
+ * @return
+ */
+extern int arith_max(int x, int y);
+
+/**
+ * Returns the minimum of two integers.
+ * @param x
+ * @param y
+ * @return
+ */
+extern int arith_min(int x, int y);
+
+/**
+ * Returns quotient of dividing |x| by |y|.
+ *
+ * When |x| and |y| are both positive or both negative, this function is equals
+ * to x / y.
+ * @param x
+ * @param y
+ * @return
+ */
+extern int arith_div(int x, int y);
+
+/**
+ * Returns remainder of dividing x by y.
+ *
+ * When |x| and |y| are both positive or both negative, this function is equals
+ * x % y.
+ *
+ * @param x
+ * @param y
+ * @return
+ */
+extern int arith_mod(int x, int y);
+
+extern int arith_ceiling(int x, int y);
+
+extern int arith_floor(int x, int y);
+
+#endif  // CII_ARITH_H_

cii/src/arith.c

@@ -0,0 +1,5 @@
+// Copyright (c) 2023 Xu Shaohua <[email protected]>. All rights reserved.
+// Use of this source is governed by GNU General Public License
+// that can be found in the LICENSE file.
+
+#include "cii/arith.h"

cii/src/set.c

@@ -2,4 +2,9 @@
 // Use of this source is governed by GNU General Public License
 // that can be found in the LICENSE file.
 
-#include "cii/set.h"
+#include "cii/set.h"
+
+#include <limits.h>
+
+#include "cii/assert.h"
+#include "cii/mem.h"