core: Add lexer + parser groundwork

Signed-off-by: Ian Moffett <ian@mirocom.org>

1 files changed, 61 insertions, 0 deletions

diff --git a/core/parser.c b/core/parser.c
new file mode 100644
index 0000000..a584a56
--- /dev/null
+++ b/core/parser.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause
+ */
+
+#include <stdint.h>
+#include <errno.h>
+#include "cescal/log.h"
+#include "cescal/parser.h"
+#include "cescal/state.h"
+#include "cescal/lexer.h"
+
+/* Symbolic token */
+#define symtok(tok) \
+    "[" tok "]"
+
+/* Quoted token */
+#define qtok(tok) \
+    "'" tok "'"
+
+/* Convert token to string */
+#define tokstr1(tt) \
+    toktab[(tt)]
+
+/* Convert token to string */
+#define tokstr(tok) \
+    toktab[(tok)->type]
+
+/*
+ * Converts numeric tokens into human readable strings
+ */
+static const char *toktab[] = {
+    [TT_NONE]   = symtok("none"),
+    [TT_IDENT]  = symtok("ident"),
+    [TT_INTLIT] = symtok("number"),
+    [TT_LPAREN] = qtok("("),
+    [TT_RPAREN] = qtok(")"),
+    [TT_COMMA]  = qtok(","),
+    [TT_RETURN] = qtok("return"),
+    [TT_PUB]    = qtok("pub"),
+    [TT_PROC]   = qtok("proc"),
+    [TT_BEGIN]  = qtok("begin"),
+    [TT_END]    = qtok("end")
+};
+
+int
+parser_parse(struct cescal_state *state)
+{
+    struct token tok;
+
+    if (state == NULL) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    while (lexer_nom(state, &tok) == 0) {
+        cc_trace("got token %s\n", tokstr(&tok));
+    }
+
+    return 0;
+}