1 files changed, 127 insertions, 0 deletions
diff --git a/cgen.c b/cgen.c
new file mode 100644
index 0000000..831a22e
--- /dev/null
+++ b/cgen.c
@@ -0,0 +1,127 @@
+/* the generation of C code */
+
+typedef struct {
+	FILE *out;
+} CGenerator;
+
+
+static void cgen_vwrite(CGenerator *g, const char *fmt, va_list args) {
+	vfprintf(g->out, fmt, args);
+}
+
+static void cgen_write(CGenerator *g, const char *fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+	cgen_vwrite(g, fmt, args);
+	va_end(args);
+}
+
+static void cgen_writeln(CGenerator *g, const char *fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+	cgen_vwrite(g, fmt, args);
+	va_end(args);
+	cgen_write(g, "\n");
+}
+	
+static void cgen_write_comment(CGenerator *g, const char *fmt, ...) {
+	cgen_write(g, "/* ");
+	va_list args;
+	va_start(args, fmt);
+	cgen_vwrite(g, fmt, args);
+	va_end(args);
+	cgen_write(g, " */");
+}
+
+static void cgen_write_line_comment(CGenerator *g, const char *fmt, ...) {
+	/* could switch to // for c99 */
+	cgen_write(g, "/* ");
+	va_list args;
+	va_start(args, fmt);
+	cgen_vwrite(g, fmt, args);
+	va_end(args);
+	cgen_write(g, " */\n");
+}
+
+static void cgen_write_ident(CGenerator *g, Identifier i) {
+	ident_fprint(g->out, i);
+}
+
+static void cgen_create(CGenerator *g, FILE *out) {
+	g->out = out;
+}
+
+static bool expr_cgen(Expression *e, CGenerator *g) {
+	switch (e->kind) {
+	case EXPR_INT_LITERAL:
+		cgen_write(g, "%lld", e->intl);
+		break;
+	case EXPR_FLOAT_LITERAL:
+		/* TODO: more precision */
+		cgen_write(g, "%f", e->floatl);
+		break;
+	case EXPR_STR_LITERAL:
+		cgen_write(g, "\"");
+		/* OPTIM: Maybe don't use i? this will probably be optimized by the compiler though... */
+		for (size_t i = 0; i < e->strl.len; i++) {
+			/* TODO: Print ordinary characters nicely */
+			cgen_write(g, "\\x%02x", e->strl.str[i]);
+		}
+		cgen_write(g, "\"");
+		break;
+	case EXPR_IDENT:
+		/* TODO: check if declared */
+		cgen_write_ident(g, e->ident); 
+		break;
+	case EXPR_BINARY_OP:
+		cgen_write(g, "(");
+		expr_cgen(e->binary.lhs, g);
+		switch (e->binary.op) {
+		case BINARY_PLUS:
+			cgen_write(g, "+");
+			break;
+		case BINARY_MINUS:
+			cgen_write(g, "-");
+			break;
+		}
+		expr_cgen(e->binary.rhs, g);
+		cgen_write(g, ")");
+		break;
+	case EXPR_UNARY_OP:
+		cgen_write(g, "(");
+		switch (e->unary.op) {
+		case UNARY_MINUS:
+			cgen_write(g, "-");
+			break;
+		}
+		expr_cgen(e->unary.of, g);
+		cgen_write(g, ")");
+		break;
+	}
+	return true;
+}
+
+static bool stmt_cgen(Statement *s, CGenerator *g) {
+	switch (s->kind) {
+	case STMT_EXPR:
+		if (!expr_cgen(&s->expr, g))
+			return false;
+		cgen_write(g, ";\n");
+		break;
+	}
+	return true;
+}
+
+static bool file_cgen(ParsedFile *f, CGenerator *g) {
+	cgen_write_line_comment(g, "toc");
+	bool ret = true;
+	arr_foreach(&f->stmts, Statement, stmt) {
+		if (stmt->kind == STMT_EXPR) {
+			/* TODO: eventually make this an error / compile-time statement */
+			warn_print(stmt->where, "Expression statement at top level.");
+		}
+		if (!stmt_cgen(stmt, g))
+			ret = false;
+	}
+	return ret;
+}