Start to rewriting code

Since there's some UB in the master I decided to rewrite code from
scratch again. I hope that attempt will be better :D

1 files changed, 118 insertions, 0 deletions

diff --git a/include/3cl.h b/include/3cl.h
new file mode 100644
index 0000000..a6b9065
--- /dev/null
+++ b/include/3cl.h
@@ -0,0 +1,118 @@
+#ifndef __3CL_H__
+#define __3CL_H__
+
+#include <stddef.h>
+#include <stdint.h>
+
+
+#ifndef CCL_STACKSIZE
+#define CCL_STACKSIZE 8192
+#endif
+
+typedef int16_t CCLNum;   /**< Abstract type for numbers in ccl */
+typedef size_t  CCLAddr;  /**< Abstract type for address in ccl */
+
+/**
+ * Type of CCLFrame
+ */
+enum CCLFrameType
+{
+    CCL_ROOT,    /**< Root frame, stores global variables    */
+    CCL_PROC,    /**< Function frame, stores local variables */
+    CCL_INFLOOP, /**< Infinity loop, stores start and repeat */
+    CCL_REPLOOP, /**< Repeat loop, stores start and repeat   */
+};
+
+/**
+ * Pair which contains variable's name and value
+ */
+struct CCLVariable
+{
+    struct CCLVariable *prev, *next;
+    char                name;
+    CCLNum              value;
+};
+
+/**
+ * Pair which contains procedure's name and address
+ */
+struct CCLProcedure
+{
+    struct CCLProcedure *prev, *next;
+    char                 name;
+    CCLAddr              address;
+};
+
+/**
+ * Pair with length of stack and stack itself
+ */
+struct CCLStack
+{
+    size_t  length;
+    size_t  cur;
+    CCLNum *stack;
+};
+
+/**
+ * Linked list that stores current state and allows to do recursion with local variables.
+ */
+struct CCLFrame
+{
+    struct  CCLFrame      *prev, *next;  /**< Frames are connected as linked list */
+    enum    CCLFrameType   type;         /**< Type of the frame                   */
+    CCLAddr                ep;           /**< Execution point                     */
+    union
+    {
+        /* Frame stores either variables (for procedures)... */
+        struct
+        {
+            struct  CCLVariable vars;    /**< For root frame variables are global */
+        };
+        /* ...or start address and repeats left (for loops) */
+        struct
+        {
+            CCLAddr start;               /**< Used by CCL_*LOOP                   */
+            int     repeats;             /**< Used by CCL_REPLOOP                 */
+        };
+    };
+};
+
+/**
+ * Main structure for 3cl. It contains root frame, stack and code it's executing.
+ */
+struct CCL
+{
+    struct CCLStack   stack;
+    struct CCLFrame   rootframe;
+    const char       *code;
+    int             (*in)();
+    void            (*out)(int);
+};
+
+/**
+ * Inits CCL.
+ * @see ccl_free
+ * @see ccl_exec
+ * @param ccl The structure to init
+ * @param code The code to execute
+ * @param in Function to get input
+ * @param out Function to show output
+ * @return 0 on success, any other number otherwise
+ */
+int ccl_init(struct CCL *ccl, const char *code, int (*in)(), void (*out)(int));
+
+/**
+ * Frees all things that ware allocated in ccl_init.
+ * @see ccl_init
+ * @param ccl The structure to free
+ */
+void ccl_free(struct CCL *ccl);
+
+/**
+ * Executes inited CCL instance
+ * @see ccl_init
+ * @param ccl The strcture to execute
+ */
+void ccl_exec(struct CCL *ccl);
+
+#endif /* __3CL_H__ */