Add parser state code and skeleton for the parsing procedure.

CMakeLists.txt

@@ -8,7 +8,7 @@ project(libabacus)
 
 add_compile_options(-pedantic -Wall)
 
-add_library(abacus STATIC src/lexer.c src/libabacus_util.c src/table.c)
+add_library(abacus STATIC src/lexer.c src/libabacus_util.c src/table.c src/parser.c)
 add_executable(libabacus src/main.c)
 add_subdirectory(external/liblex)
 

include/parser.h

@@ -0,0 +1,16 @@
+#ifndef LIBABACUS_PARSER_H
+#define LIBABACUS_PARSER_H
+
+#include "table.h"
+#include "ll.h"
+#include "tree.h"
+
+/**
+ * Parses the given list of tokens into the given tree pointer.
+ * @param tokens the tokens to use for parsing.
+ * @param string the string to use for determining token values.
+ * @param store_into tree pointer to store the new data into.
+ */
+libab_result parse_tokens(ll* tokens, const char* string, tree** store_into);
+
+#endif

src/parser.c

@@ -0,0 +1,29 @@
+struct parser_state {
+    ll_node* current_node;
+    lexer_match* current_match;
+    const char* string;
+};
+
+void _parser_state_update(struct parser_state* state) {
+    state->current_match = state->current_node ? state->current_node->data : NULL;
+}
+
+void _parser_state_init(struct parser_state* state, ll* tokens, const char* string) {
+    state->current_node = tokens->head;
+    state->string = string;
+    _parser_state_update(state);
+}
+
+void _parser_state_step(struct parser_state* state) {
+    if(state->current_node) {
+        state->current_node = state->current_node->next;
+    }
+    _parser_state_update(state);
+}
+libab_result parse_tokens(ll* tokens, const char* string, tree** store_into) {
+    libab_result result = LIBAB_SUCCESS;
+    struct parser_state state;
+    _parser_state_init(&state, tokens, string);
+
+    return result;
+}