Add runtime specs

include/runtime.h

@@ -0,0 +1,71 @@
+#ifndef tree_sitter_runtime_h
+#define tree_sitter_runtime_h
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdlib.h>
+
+#pragma mark - Tree
+
+typedef struct {
+} TSTree;
+    
+TSTree TSTreeMake();
+
+#pragma mark - Parser
+
+typedef size_t TSSymbol;
+typedef int TSState;
+    
+typedef struct {
+    TSTree tree;
+    const char *input;
+    size_t position;
+    TSState *state_stack;
+    TSSymbol *symbol_stack;
+    size_t state_count;
+    size_t symbol_count;
+} TSParser;
+
+TSParser TSParserMake(const char *input);
+void TSParserShift(TSParser *parser, TSState state);
+void TSParserReduce(TSParser *parser, TSSymbol symbol, int child_count);
+void TSParserError(TSParser *parser);
+TSState TSParserState(const TSParser *parser);
+TSSymbol TSParserLookahead(const TSParser *parser);
+
+#pragma mark - DSL
+
+#define START_PARSER() \
+    TSParser parser = TSParserMake(input); \
+    start:
+
+#define LOOKAHEAD() \
+    TSParserLookahead(&parser)
+
+#define PARSE_STATE() \
+    TSParserState(&parser)
+
+#define SHIFT(number) \
+    { TSParserShift(&parser, number); break; }
+
+#define ACCEPT() \
+    { goto done; }
+
+#define REDUCE(symbol, child_count) \
+    { TSParserReduce(&parser, symbol, child_count); break; }
+
+#define ERROR() \
+    TSParserError(&parser)
+
+#define FINISH_PARSER() \
+    done: \
+    return parser.tree;
+
+#endif
+    
+#ifdef __cplusplus
+}
+#endif