add pic_state structure

include/picrin.h

@@ -0,0 +1,10 @@
+#ifndef PICRIN_H__
+#define PICRIN_H__
+
+typedef struct {
+} pic_state;
+
+pic_state *pic_open();
+void pic_close(pic_state *pic);
+
+#endif

src/main.c

@@ -1,13 +1,18 @@
 #include <stdio.h>
 
+#include "picrin.h"
+
 #define LINE_MAX_LENGTH 256
 
 int
 main()
 {
+  pic_state *pic;
   char line[LINE_MAX_LENGTH], last_char;
   int char_index;
 
+  pic = pic_open();
+
   while (1) {
     printf("> ");
 
@@ -36,5 +41,7 @@ main()
   goto exit;
 
  exit:
+  pic_close(pic);
+
   return 0;
 }

src/state.c

@@ -0,0 +1,19 @@
+#include <stdlib.h>
+
+#include "picrin.h"
+
+pic_state *
+pic_open()
+{
+  pic_state *pic;
+
+  pic = (pic_state *)calloc(sizeof(pic_state));
+
+  return pic;
+}
+
+void
+pic_close(pic_state *pic)
+{
+  free(pic);
+}