From f2b768eabaa99ebb0acf5454823871ddf5675a59 Mon Sep 17 00:00:00 2001
From: Lee Lup Yuen <luppy@appkaki.com>
Date: Mon, 5 Jun 2023 13:02:06 +0800
Subject: [PATCH] Refactor for NuttX

---
 feature-phone.zig |  2 +-
 nuttx.zig         | 69 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/feature-phone.zig b/feature-phone.zig
index c1d875c..fe94239 100644
--- a/feature-phone.zig
+++ b/feature-phone.zig
@@ -179,7 +179,7 @@ export fn eventHandler(e: ?*c.lv_event_t) void {
             if (builtin.cpu.arch == .wasm32 or builtin.cpu.arch == .wasm64) {
                 debug("Running in WebAssembly, simulate the Phone Call", .{});
             } else {
-                debug("Running on PinePhone, make an actual Phone Call", {});
+                debug("Running on PinePhone, make an actual Phone Call", .{});
             }
         } else if (std.mem.eql(u8, span, "Cancel")) {
             // If Cancel is clicked, erase the last digit
diff --git a/nuttx.zig b/nuttx.zig
index 34ccbc0..59a2f77 100644
--- a/nuttx.zig
+++ b/nuttx.zig
@@ -1 +1,70 @@
 //! LVGL Functions specific to Apache NuttX RTOS
+
+/// Import the Zig Standard Library
+const std = @import("std");
+const builtin = @import("builtin");
+
+///////////////////////////////////////////////////////////////////////////////
+//  Panic Handler
+
+/// Called by Zig when it hits a Panic. We print the Panic Message, Stack Trace and halt. See
+/// https://andrewkelley.me/post/zig-stack-traces-kernel-panic-bare-bones-os.html
+/// https://github.com/ziglang/zig/blob/master/lib/std/builtin.zig#L763-L847
+pub fn panic(message: []const u8, _stack_trace: ?*std.builtin.StackTrace) noreturn {
+    // Print the Panic Message
+    _ = _stack_trace;
+    _ = puts("\n!ZIG PANIC!");
+    _ = puts(@ptrCast([*c]const u8, message));
+
+    // Print the Stack Trace
+    _ = puts("Stack Trace:");
+    var it = std.debug.StackIterator.init(@returnAddress(), null);
+    while (it.next()) |return_address| {
+        _ = printf("%p\n", return_address);
+    }
+
+    // Halt
+    while (true) {}
+}
+
+///////////////////////////////////////////////////////////////////////////////
+//  Logging
+
+/// Called by Zig for `std.log.debug`, `std.log.info`, `std.log.err`, ...
+/// https://gist.github.com/leecannon/d6f5d7e5af5881c466161270347ce84d
+pub fn log(
+    comptime _message_level: std.log.Level,
+    comptime _scope: @Type(.EnumLiteral),
+    comptime format: []const u8,
+    args: anytype,
+) void {
+    _ = _message_level;
+    _ = _scope;
+
+    // Format the message
+    var buf: [100]u8 = undefined; // Limit to 100 chars
+    var slice = std.fmt.bufPrint(&buf, format, args) catch {
+        _ = puts("*** log error: buf too small");
+        return;
+    };
+
+    // Terminate the formatted message with a null
+    var buf2: [buf.len + 1:0]u8 = undefined;
+    std.mem.copy(u8, buf2[0..slice.len], slice[0..slice.len]);
+    buf2[slice.len] = 0;
+
+    // Print the formatted message
+    _ = puts(&buf2);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+//  Imported Functions and Variables
+
+/// For safety, we import these functions ourselves to enforce Null-Terminated Strings.
+/// We changed `[*c]const u8` to `[*:0]const u8`
+extern fn printf(format: [*:0]const u8, ...) c_int;
+extern fn puts(str: [*:0]const u8) c_int;
+
+/// Aliases for Zig Standard Library
+const assert = std.debug.assert;
+const debug = std.log.debug;