1 files changed, 35 insertions, 1 deletions

diff --git a/src/main.zig b/src/main.zig
index 62877cb..7a0513e 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -1,8 +1,42 @@
 const std = @import("std");
+pub const Grammar = @import("grammar.zig");
+pub const recognizer = @import("recognizer.zig");
 
-pub const grammar = @import("grammar.zig");
+fn help() !noreturn {
+	const stderr = std.io.getStdErr().writer();
+	try stderr.print("gll [grammar] [input]\n", .{});
+	std.process.exit(1);
+}
+
+fn read_whole_file(path: []const u8, allocator: std.mem.Allocator) ![]const u8 {
+	const file = try std.fs.cwd().openFile(path, .{});
+	defer file.close();
+	const stat = try file.stat();
+	return file.readToEndAlloc(allocator, stat.size);
+}
 
 pub fn main() !void {
+	var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+	const allocator = gpa.allocator();
+	defer {
+		if (gpa.deinit() == .leak) {
+			@panic("memory leak detected");
+		}
+	}
+	
+	var args = std.process.args();
+	_ = args.next();
+
+	const grammar_path = args.next() orelse try help();
+	const input_path = args.next() orelse try help();
+
+	const grammar_text = try read_whole_file(grammar_path, allocator);
+	defer allocator.free(grammar_text);
+	const input = try read_whole_file(input_path, allocator);
+	defer allocator.free(input);
+
+	var grammar = try Grammar.parse(grammar_text, allocator);
+	defer grammar.deinit(allocator);
 }
 
 test {