Taskified cheevos

cheevos/coro.h

@@ -0,0 +1,83 @@
+#ifndef CORO_H
+#define CORO_H
+
+/*
+Released under the CC0: https://creativecommons.org/publicdomain/zero/1.0/
+*/
+
+/* Use at the beginning of the coroutine, you must have declared a variable coro_t* coro */
+#define CORO_ENTER() \
+  { \
+  CORO_again: ; \
+  switch ( coro->step ) { \
+  case CORO_BEGIN: ;
+
+/* Use to define labels which are targets to GOTO and GOSUB */
+#define CORO_SUB( x ) \
+  case x: ;
+
+/* Use at the end of the coroutine */
+#define CORO_LEAVE() \
+  } \
+  } \
+  do { return 0; } while ( 0 )
+
+/* Go to the x label */
+#define CORO_GOTO( x ) \
+  do { \
+    coro->step = ( x ); \
+    goto CORO_again; \
+  } while ( 0 )
+
+/* Go to a subroutine, execution continues until the subroutine returns via RET */
+/* x is the subroutine label, y and z are the A and B arguments */
+#define CORO_GOSUB( x ) \
+  do { \
+    coro->stack[ coro->sp++ ] = __LINE__; \
+    coro->step = ( x ); \
+    goto CORO_again; \
+    case __LINE__: ; \
+  } while ( 0 )
+
+/* Returns from a subroutine */
+#define CORO_RET() \
+  do { \
+    coro->step = coro->stack[ --coro->sp ]; \
+    goto CORO_again; \
+  } while ( 0 )
+
+/* Yields to the caller, execution continues from this point when the coroutine is resumed */
+#define CORO_YIELD() \
+  do { \
+    coro->step = __LINE__; \
+    return 1; \
+    case __LINE__: ; \
+  } while ( 0 )
+
+#define CORO_STOP() \
+  do { \
+    return 0; \
+  } while ( 0 )
+
+/* The coroutine entry point, never use 0 as a label */
+#define CORO_BEGIN 0
+
+/* Sets up a coroutine, x is a pointer to coro_t */
+#define CORO_SETUP( x ) \
+  do { \
+    ( x )->step = CORO_BEGIN; \
+    ( x )->sp = 0; \
+  } while ( 0 )
+
+#define CORO_VAR( x ) ( coro->x )
+
+/* A coroutine */
+typedef struct
+{
+  CORO_VARS
+  int step, sp;
+  int stack[ 8 ];
+}
+coro_t;
+
+#endif /* CORO_H */