kernel: Add a fun splash screen during boot :)

Mostly for fun.
Has a lot of delay in order to see the actual splash screen.

apps/app.c

@@ -10,7 +10,7 @@ void bye()
 int main()
 {
     atexit(bye);
-    printf("Welcome to %s!\n", "Luna");
+    printf("Welcome to %s from userspace!\n", "Luna");
 
     char* address = (char*)malloc(1);
     printf("address: %p\n", address);

kernel/debug.cmake

@@ -1,2 +1,3 @@
 target_compile_definitions(moon PRIVATE LOCKED_VALUE_DEBUG)
+target_compile_definitions(moon PRIVATE DEBUG_MODE)
 target_compile_options(moon PRIVATE -fsanitize=undefined)

kernel/src/boot/Init.cpp

@@ -25,7 +25,12 @@ void Init::early_init()
 
     Framebuffer::init();
 
-    setup_log(log_debug_enabled(), log_serial_enabled(), true);
+#ifdef DEBUG_MODE
+    constexpr bool should_log_console = true;
+#else
+    constexpr bool should_log_console = false;
+#endif
+    setup_log(log_debug_enabled(), log_serial_enabled(), should_log_console);
 
     CPU::platform_init();
 

kernel/src/main.cpp

@@ -12,18 +12,12 @@
 #include "memory/KernelVM.h"
 #include "memory/MemoryManager.h"
 #include "thread/Scheduler.h"
+#include "video/Framebuffer.h"
+#include "video/TextConsole.h"
 #include <luna/CString.h>
 #include <luna/Result.h>
 #include <luna/Units.h>
 
-void heap_thread()
-{
-    CPU::disable_interrupts();
-    dump_heap_usage();
-    kdbgln("Kernel uses %lu vm pages", KernelVM::used() / ARCH_PAGE_SIZE);
-    kernel_exit();
-}
-
 void reap_thread()
 {
     while (true)
@@ -38,24 +32,23 @@ void reap_thread()
     }
 }
 
-Result<void> init()
+static void identify_processor()
 {
-    kinfoln("Starting Moon %s, built on %s at %s", MOON_VERSION, __DATE__, __TIME__);
-
     kinfoln("Current platform: %s", CPU::platform_string());
 
     kinfoln("Current processor: %s", CPU::identify().value_or("(unknown)"));
+}
 
-    Timer::init();
-
+static void identify_memory()
+{
     kinfoln("Total memory:    %s", to_dynamic_unit(MemoryManager::total()).release_value().chars());
     kinfoln("Free memory:     %s", to_dynamic_unit(MemoryManager::free()).release_value().chars());
     kinfoln("Used memory:     %s", to_dynamic_unit(MemoryManager::used()).release_value().chars());
     kinfoln("Reserved memory: %s", to_dynamic_unit(MemoryManager::reserved()).release_value().chars());
+}
 
-    Thread::init();
-    Scheduler::init();
-
+static Result<void> try_init_vfs()
+{
     VFS::root_fs = TRY(TmpFS::FileSystem::create());
 
     VFS::Inode& root_inode = VFS::root_inode();
@@ -68,6 +61,16 @@ Result<void> init()
 
     kinfoln("root inode's 'usr' entry inode number: %zu", TRY(root_inode.find("usr"))->inode_number());
 
+    return {};
+}
+
+static void init_vfs()
+{
+    try_init_vfs().release_value();
+}
+
+static Result<void> try_init_userspace()
+{
     TarStream::Entry entry;
     while (TRY(g_initrd.read_next_entry(entry)))
     {
@@ -80,22 +83,96 @@ Result<void> init()
         }
     }
 
-    TRY(Scheduler::new_kernel_thread(heap_thread));
-    TRY(Scheduler::new_kernel_thread(reap_thread));
+    return {};
+}
 
+static void init_userspace()
+{
+    try_init_userspace().release_value();
+}
+
+static void create_reaper()
+{
+    Scheduler::new_kernel_thread(reap_thread).release_value();
+}
+
+static void scan_pci()
+{
     PCI::scan(
         [](const PCI::Device& device) {
             kinfoln("Found PCI mass storage device %.4x:%.4x, at address %u:%u:%u", device.id.vendor, device.id.device,
                     device.address.bus, device.address.slot, device.address.function);
         },
         { .klass = 1 });
+}
 
-    CPU::platform_finish_init();
-
+static void transfer_control()
+{
     // Disable console logging before transferring control to userspace.
     setup_log(log_debug_enabled(), log_serial_enabled(), false);
 
     CPU::enable_interrupts();
+}
+
+struct SplashAction
+{
+    const char* message;
+    void (*action)(void);
+};
+
+constexpr SplashAction actions[] = {
+    { "Identify Processor", identify_processor },  { "Initialize Timer", Timer::init },
+    { "Identify System Memory", identify_memory }, { "Initialize Threads", Thread::init },
+    { "Initialize Scheduler", Scheduler::init },   { "Initialize File System", init_vfs },
+    { "Initialize Userspace", init_userspace },    { "Create Reaper Thread", create_reaper },
+    { "Find Available Devices", scan_pci },        { "Final CPU Initialization", CPU::platform_finish_init },
+    { "Start Userspace", transfer_control },
+};
+
+static constexpr u32 WHITE = 0xffffffff;
+static constexpr u32 RED = 0xffff0000;
+static constexpr u32 BLACK = 0xff000000;
+
+static void update_splash(const char* message, u32 current, u32 total)
+{
+    const u32 line_height = Framebuffer::height() / 2;
+    const u32 line_begin = 100;
+    const u32 line_length = Framebuffer::width() - 200;
+
+    if (current != total)
+    {
+        const u32 line_completed = (line_length / total) * current;
+
+        Framebuffer::rect(line_begin, line_height, line_completed, 2, WHITE);
+        Framebuffer::rect(line_begin + line_completed, line_height, line_length - line_completed, 2, RED);
+    }
+    else { Framebuffer::rect(line_begin, line_height, line_length, 2, WHITE); }
+
+    Framebuffer::rect(line_begin, line_height + 20, line_length, 16, BLACK);
+
+    TextConsole::move_to(Framebuffer::width() / 2 - 100, line_height + 20);
+    TextConsole::print(message).release_value();
+
+    TextConsole::move_to(0, 0);
+
+    for (int i = 0; i < 3000000; i++) CPU::pause();
+}
+
+Result<void> init()
+{
+    kinfoln("Starting Moon %s, built on %s at %s", MOON_VERSION, __DATE__, __TIME__);
+
+    constexpr usize total_actions = sizeof(actions) / sizeof(actions[0]);
+
+    for (usize i = 0; i < total_actions; i++)
+    {
+#ifndef DEBUG_MODE
+        update_splash(actions[i].message, (u32)i, (u32)(total_actions - 1));
+#else
+        (void)update_splash;
+#endif
+        actions[i].action();
+    }
 
     return {};
 }