feat: initial booting kernel, copy libc stuff from myke

yak-kernel/src/rt/kmain.c

@@ -0,0 +1,13 @@
+#include <yak/rt/kmain.h>
+#include <yak/rt/panic.h>
+#include "yak/platform/generic/platform.h"
+
+void kmain() {
+    // kmain is called from one of the bootloader implementations
+
+    // perform platform specific initialisation
+    platform_init();
+
+    // this should (eventually) be unreachable
+    panic("End of kmain");
+}

yak-kernel/src/rt/kprint.c

@@ -0,0 +1,44 @@
+//
+// Created by rick on 21-3-23.
+//
+
+#include <yak/rt/kprint.h>
+#include <stddef.h>
+
+#define MAX_PRINT_FUNCTIONS 8
+
+print_function print_functions[MAX_PRINT_FUNCTIONS] = {0};
+
+void kprint_now(char* msg) {
+    char* m = msg;
+    while (*m != 0) {
+        kprint_putc_now(*m);
+        m++;
+    }
+}
+
+void kprint_putc_now(char c) {
+    for (int i = 0; i < MAX_PRINT_FUNCTIONS; ++i) {
+        if (print_functions[i] != NULL) {
+            print_functions[i](c);
+        }
+    }
+}
+
+void kprint_register(print_function print) {
+    for (int i = 0; i < MAX_PRINT_FUNCTIONS; ++i) {
+        if (print_functions[i] == NULL) {
+            print_functions[i] = print;
+            break;
+        }
+    }
+}
+
+void kprint_unregister(print_function print) {
+    for (int i = 0; i < MAX_PRINT_FUNCTIONS; ++i) {
+        if (print_functions[i] == print) {
+            print_functions[i] = NULL;
+            break;
+        }
+    }
+}

yak-kernel/src/rt/limine/limine.c

@@ -0,0 +1,114 @@
+//
+// Created by rick on 21-3-23.
+//
+
+#include <stddef.h>
+#include <stdio.h>
+#include <limine.h>
+#include <yak/rt/kprint.h>
+#include <yak/rt/kmain.h>
+
+static struct limine_bootloader_info_request limine_bootloader_info_request = {
+        .id = LIMINE_BOOTLOADER_INFO_REQUEST,
+        .revision = 0,
+};
+
+static struct limine_framebuffer_request limine_framebuffer_request = {
+    .id = LIMINE_FRAMEBUFFER_REQUEST,
+    .revision = 0,
+};
+
+static struct limine_terminal_request limine_terminal_request = {
+        .id = LIMINE_TERMINAL_REQUEST,
+        .revision = 0
+};
+
+// unused: 5 level paging
+// unused: SMP
+
+struct limine_memmap_request limine_memmap_request = {
+        .id = LIMINE_MEMMAP_REQUEST,
+        .revision = 0,
+};
+
+void limine_init();
+struct limine_entry_point_request limine_entry_point_request = {
+        .id = LIMINE_ENTRY_POINT_REQUEST,
+        .revision = 0,
+        .entry = limine_init,
+};
+
+struct limine_kernel_file_request limine_kernel_file_request = {
+        .id = LIMINE_KERNEL_FILE_REQUEST,
+        .revision = 0,
+};
+
+struct limine_module_request limine_module_request = {
+        .id = LIMINE_MODULE_REQUEST,
+        .revision = 0,
+};
+
+struct limine_rsdp_request limine_rsdp_request = {
+        .id = LIMINE_RSDP_REQUEST,
+        .revision = 0,
+};
+
+struct limine_smbios_request limine_smbios_request = {
+        .id = LIMINE_SMBIOS_REQUEST,
+        .revision = 0,
+};
+
+struct limine_efi_system_table_request limine_efi_system_table_request = {
+        .id = LIMINE_EFI_SYSTEM_TABLE_REQUEST,
+        .revision = 0,
+};
+
+struct limine_boot_time_request limine_boot_time_request = {
+        .id = LIMINE_BOOT_TIME_REQUEST,
+        .revision = 0,
+};
+
+struct limine_kernel_address_request limine_kernel_address_request = {
+        .id = LIMINE_KERNEL_ADDRESS_REQUEST,
+        .revision = 0,
+};
+
+struct limine_dtb_request limine_dtb_request = {
+        .id = LIMINE_DTB_REQUEST,
+        .revision = 0,
+};
+
+static volatile __attribute__((used, section(".limine_reqs"))) void* limine_requests[] = {
+        &limine_bootloader_info_request,
+        &limine_framebuffer_request,
+        &limine_terminal_request,
+        &limine_memmap_request,
+        &limine_entry_point_request,
+        &limine_kernel_file_request,
+        &limine_module_request,
+        &limine_rsdp_request,
+        &limine_smbios_request,
+        &limine_efi_system_table_request,
+        &limine_boot_time_request,
+        &limine_kernel_address_request,
+        &limine_dtb_request,
+        NULL,
+};
+
+void limine_terminal_kprint(char c) {
+    limine_terminal_request.response->write(limine_terminal_request.response->terminals[0], &c, 1);
+}
+
+void limine_init() {
+    if (limine_terminal_request.response != NULL && limine_terminal_request.response->terminal_count >= 1) {
+        kprint_register(limine_terminal_kprint);
+    }
+
+    if (limine_bootloader_info_request.response != NULL) {
+        printf("Booted using limine from %s %s\n", limine_bootloader_info_request.response->name, limine_bootloader_info_request.response->version);
+    } else {
+        printf("Booted using limine from an unknown bootloader\n");
+    }
+
+    kmain();
+}

yak-kernel/src/rt/panic.c

@@ -0,0 +1,15 @@
+//
+// Created by rick on 21-3-23.
+//
+
+#include <yak/rt/panic.h>
+#include "yak/rt/kprint.h"
+#include "yak/platform/generic/platform.h"
+
+void __attribute__((__noreturn__)) panic(char *reason) {
+    kprint_now(reason);
+
+    // todo stack trace
+
+    halt_forever();
+}

yak-kernel/src/rt/stack_protection.c

@@ -0,0 +1,21 @@
+//
+// Created by rick on 21-3-23.
+//
+
+#include <stdint.h>
+
+#include <yak/rt/panic.h>
+
+#if UINT32_MAX == UINTPTR_MAX
+#define STACK_CHK_GUARD 0xe2dee396
+#else
+#define STACK_CHK_GUARD 0x595e9fbd94fda766
+#endif
+
+// todo this value should be unique every time the kernel starts
+uintptr_t __stack_chk_guard = STACK_CHK_GUARD;
+
+void __attribute__((__noreturn__)) __stack_chk_fail() {
+    panic("Stack Smashed");
+}
+