remove generics from io interface

src/frontend/ncurses.zig

@@ -31,6 +31,7 @@ const KEY_QUIT: i32 = ncurses.KEY_F(1);
 
 /// Provide an IO struct that manages the state of the display and user input
 pub const IO = struct {
+    allocator: std.mem.Allocator,
     main: ?*ncurses.WINDOW,
     inst: ?*ncurses.WINDOW,
     msgs: ?*ncurses.WINDOW,
@@ -64,7 +65,11 @@ pub const IO = struct {
         } else if (key < 128) {
             _ = ncurses.mvwprintw(self.inst, pos, 2, "%c - %s", key, c_description);
         } else {
-            self.displayMessage("Invalid key name: {d}", .{key});
+            const str = std.fmt.allocPrintZ(self.allocator, "Invalid key name: {d}", .{key}) catch {
+                return;
+            };
+            self.displayMessage(str);
+            self.allocator.free(str);
         }
     }
 
@@ -112,9 +117,9 @@ pub const IO = struct {
     }
 
     /// Display a message in the message box.
-    /// Takes a format string and arguments.
+    /// Takes a pre-formatted null-terminated string
     /// If the message is too wide for the box, display "Message too long" instead.
-    pub fn displayMessage(self: *IO, comptime fmt: []const u8, args: anytype) void {
+    pub fn displayMessage(self: *IO, str: [:0]const u8) void {
         if (self.msgs == null) return;
 
         for (1..MESSAGE_PANEL_WIDTH - 1) |i| {
@@ -122,12 +127,14 @@ pub const IO = struct {
             _ = ncurses.mvwaddch(self.msgs, 1, i_32, ' ');
         }
 
-        var buf: [MESSAGE_PANEL_WIDTH:0]u8 = undefined;
-        const data = std.fmt.bufPrint(&buf, fmt, args) catch {
-            self.displayMessage("Message too long", .{});
+        if (str.len > MESSAGE_PANEL_WIDTH - 2) {
+            self.displayMessage("Message too long");
             return;
-        };
-        buf[data.len] = 0;
+        }
+
+        var buf: [MESSAGE_PANEL_WIDTH:0]u8 = undefined;
+        std.mem.copyForwards(u8, &buf, str);
+        buf[str.len] = 0;
 
         const msg: [:0]u8 = &buf;
 
@@ -226,10 +233,11 @@ pub const IO = struct {
         );
     }
 
-    pub fn init() !IO {
+    pub fn init(allocator: std.mem.Allocator) !IO {
         _ = locale.setlocale(locale.LC_ALL, "");
 
         var io = IO{
+            .allocator = allocator,
             .inst = null,
             .msgs = null,
             .stat = null,

src/main.zig

@@ -3,25 +3,35 @@ const IO = @import("frontend/ncurses.zig").IO;
 const Action = @import("actions.zig").Action;
 
 pub fn main() u8 {
-    var io = IO.init() catch |err| {
+    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+    const allocator = gpa.allocator();
+    var io = IO.init(allocator) catch |err| {
         std.log.err("{}", .{err});
         return 1;
     };
     defer io.deinit();
 
-    io.displayMessage("Initialized", .{});
+    io.displayMessage("Initialized");
 
     var action = Action.illegal;
     var tick_count: usize = 0;
     while (action != Action.exit) {
-        io.displayMessage("{}", .{tick_count});
+        var str = std.fmt.allocPrintZ(allocator, "{}", .{tick_count}) catch {
+            return 1;
+        };
+        io.displayMessage(str);
+        allocator.free(str);
         action = io.waitForTick();
         switch (action) {
             Action.tick => {
-                io.displayMessage("{}", .{tick_count});
+                str = std.fmt.allocPrintZ(allocator, "{}", .{tick_count}) catch {
+                    return 1;
+                };
+                io.displayMessage(str);
+                allocator.free(str);
                 tick_count += 1;
             },
-            else => io.displayMessage("{}", .{tick_count}),
+            else => {},
         }
     }