stone.h

   1 #ifndef ZZGO_STONE_H
   2 #define ZZGO_STONE_H
   3
   4 enum stone {
   5         S_NONE,
   6         S_BLACK,
   7         S_WHITE,
   8         S_OFFBOARD,
   9         S_MAX,
  10 };
  11
  12 static char stone2char(enum stone s);
  13 static enum stone char2stone(char s);
  14 char *stone2str(enum stone s); /* static string */
  15 enum stone str2stone(char *str);
  16
  17 static enum stone stone_other(enum stone s);
  18
  19
  20 static inline char
  21 stone2char(enum stone s)
  22 {
  23         return ".XO#"[s];
  24 }
  25
  26 static inline enum stone
  27 char2stone(char s)
  28 {
  29         switch (s) {
  30                 case '.': return S_NONE;
  31                 case 'X': return S_BLACK;
  32                 case 'O': return S_WHITE;
  33                 case '#': return S_OFFBOARD;
  34         }
  35         return S_NONE; // XXX
  36 }
  37
  38 /* Curiously, gcc is reluctant to inline this; I have cofirmed
  39  * there is performance benefit. */
  40 static inline enum stone __attribute__((always_inline))
  41 stone_other(enum stone s)
  42 {
  43         static const enum stone o[S_MAX] = { S_NONE, S_WHITE, S_BLACK, S_OFFBOARD };
  44         return o[s];
  45 }
  46
  47 #endif