1 files changed, 112 insertions, 0 deletions
diff --git a/var.c b/var.c
new file mode 100644
index 0000000..658f00b
--- /dev/null
+++ b/var.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2026 Nakidai Perumenei <nakidai at disroot dot org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "thac.h"
+
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+long
+findvar(char *name, struct scope **scope)
+{
+	struct var *var;
+	ulong i;
+
+	for (; *scope; *scope = (*scope)->parent) for (i = 0; i < (*scope)->len; ++i)
+	{
+		var = &(*scope)->vars[i];
+		if (!strcmp(var->name, name))
+			return i;
+	}
+
+	return -1;
+}
+
+ulong
+assignvar(char *name, struct val val, struct scope **scope)
+{
+	struct scope *lscope;
+	long i;
+
+	lscope = *scope;
+	i = findvar(name, &lscope);
+	if (i < 0)
+	{
+		/* TODO: add cap and increment like in lex.c */
+		(*scope)->vars = realloc(
+			(*scope)->vars,
+			sizeof(*(*scope)->vars) * ++(*scope)->len
+		);
+		if (!(*scope)->vars)
+			dieno(1, "realloc()");
+		i = (*scope)->len - 1;
+	} else
+	{
+		scope = &lscope;
+	}
+	(*scope)->vars[i].name = name;
+	(*scope)->vars[i].val = val;
+	return i;
+}
+
+int
+varnextchar(struct scope *scope)
+{
+	struct var *var;
+	ulong i;
+	int c;
+
+	for (c = -1; scope; scope = scope->parent) for (i = 0; i < scope->len; ++i)
+	{
+		var = &scope->vars[i];
+		if (var->name[0] == '@' && islower(var->name[1]))
+			c = max(c, var->name[1]);
+
+		if (c == -1)
+			continue;
+
+		if (c == 'z')
+			return -1;
+		return var->name[1] + 1;
+	}
+
+	return 'a';
+}
+
+ulong
+varnextnum(struct scope *scope)
+{
+	struct var *var;
+	ulong i;
+
+	for (; scope; scope = scope->parent) for (i = 0; i < scope->len; ++i)
+	{
+		var = &scope->vars[i];
+		if (var->name[0] == '@' && isdigit(var->name[1]))
+			return atoll(&var->name[1]) + 1;
+	}
+
+	return 0;
+}
+
+void
+delvarscope(struct scope *scope, ulong i)
+{
+	freeval(scope->vars[i].val);
+	scope->vars[i] = scope->vars[--scope->len];
+}