From 7398da96623a5d2b165928d26ce8ae6364357d94 Mon Sep 17 00:00:00 2001
From: Quinten Kock <quinten@quinten.space>
Date: Wed, 23 Dec 2020 04:11:00 +0100
Subject: [PATCH] add basic and highly inaccurate time support

---
 kernel/src/main.c   |  3 +--
 kernel/src/main.zig | 17 +++++++++++++++--
 kernel/src/time.zig | 41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 57 insertions(+), 4 deletions(-)
 create mode 100644 kernel/src/time.zig

diff --git a/kernel/src/main.c b/kernel/src/main.c
index 456bdcf..31b45c3 100644
--- a/kernel/src/main.c
+++ b/kernel/src/main.c
@@ -13,6 +13,7 @@ void kmain() {
 	}
 	printf("Kernel initialized! Platform: %s\n", arch);
 	printf("Bootloader type: %s (%s %s)\n", boot_info.boot_protocol, boot_info.bootloader_name, boot_info.bootloader_ver);
+	setEpoch(boot_info.epoch);
 	printf("System time: %d\n", boot_info.epoch);
 	printf("Usable memory: %h (at %x)\n", boot_info.usable.len, boot_info.usable.start);
 	printf("Cmdline: %s\n", boot_info.cmdline);
@@ -23,8 +24,6 @@ void kmain() {
 	// memcpy(PRINTBUF, TESTBUF, 32);
 	// puts(PRINTBUF);
 	
-	kalloc_init(boot_info.usable.start, boot_info.usable.len);
-
 	vga_setcolor(VGA_DARK_GRAY);
 	vga_write_elsewhere("(c) Quinten Kock 2020 (MIT License)", 24, 0);
 	halt_catch_fire();
diff --git a/kernel/src/main.zig b/kernel/src/main.zig
index 11c8271..ca9be3b 100644
--- a/kernel/src/main.zig
+++ b/kernel/src/main.zig
@@ -2,11 +2,14 @@ const std = @import("std");
 const builtin = @import("builtin");
 const debug = @import("debug.zig");
 const kalloc = @import("allocator/kalloc.zig");
+const time = @import("time.zig");
 
 pub fn panic(msg: []const u8, error_return_trace: ?*std.builtin.StackTrace) noreturn {
     debug.zigpanic(msg, error_return_trace);
 }
 
+pub var alloc: *std.mem.Allocator = &kalloc.KAlloc.allocator;
+
 pub const log_level = .debug;
 pub fn log(
     comptime level: std.log.Level,
@@ -19,6 +22,7 @@ pub fn log(
 
 comptime {
     _ = debug;
+    _ = time;
 }
 
 const c = @cImport({
@@ -26,6 +30,7 @@ const c = @cImport({
     @cInclude("hal/print.h");
     @cInclude("print/print.h");
     @cInclude("hal/ops.h");
+    @cInclude("hal/info.h");
     if( builtin.cpu.arch == .x86_64 or builtin.cpu.arch == .i386) {
         @cInclude("arch/x86/vga.h");
     }
@@ -35,10 +40,18 @@ export fn zigmain() void {
     // // const message: [*:0]const u8 = "hello, zig!\n";
     std.log.info("All your codebase are belong to us.", .{});
 
-    std.log.debug("CPU info: {}", .{builtin.cpu});
+    std.log.debug("CPU info: {} ({})", .{builtin.cpu.arch, builtin.cpu.model.name});
     c.puts("zig ee\n");
 
-    kalloc.kallocNop();
+    const msg = std.fmt.allocPrint(alloc, "Hello {}!", .{"ziguser"});
+    std.log.debug("message: {}", .{msg});
+
+    // time.displayTime(debug.AWriter) catch unreachable;
+
+    const cmdline = std.mem.span(c.boot_info.cmdline);
+
+    std.log.info("cmdline: {}", .{cmdline});
+
 
     // @panic("ee");
 
diff --git a/kernel/src/time.zig b/kernel/src/time.zig
new file mode 100644
index 0000000..47f200a
--- /dev/null
+++ b/kernel/src/time.zig
@@ -0,0 +1,41 @@
+const std = @import("std");
+
+var boot_epoch: u64 = undefined;
+var epoch: u64 = 0;
+
+fn year_is_leap(y: u16) bool {
+    return (y%4) == 0;
+}
+
+pub const DateTime = struct {
+    year: u16,
+    month: u8,
+    day: u16,
+    hours: u8,
+    mins: u8,
+    secs: u8,
+
+    fn fromEpoch(e: u64) DateTime {
+        // const year = 1970;
+        // var yearlen = if(year_is_leap(year)) 
+
+        const year = 1970 + (e / 31556926);
+        const days = (e % 31556926) / 86400;
+        return .{
+            .secs = @intCast(u8, e % 60),
+            .mins = @intCast(u8, (e/60) % 60),
+            .hours = @intCast(u8, (e /3600) % 60),
+            .day = @intCast(u16, days),
+            .month = 0,
+            .year = @intCast(u16, year),
+        };
+    }
+};
+
+export fn setEpoch(e: u64) void {
+    boot_epoch = e;
+}
+
+pub fn displayTime(w: anytype) !void {
+    try w.print("{}", .{DateTime.fromEpoch(boot_epoch)});
+}
\ No newline at end of file