feat: added shutdown command

kernel/command.c

@@ -19,6 +19,7 @@
 #include <libc/readline.h>
 #include <libc/libc.h>
 #include <attributes.h>
+#include <util/power.h>
 
 #define BOOTLOADER_NAME_MAX_LENGTH 64
 #define CMDLINE_MAX_LENGTH 256
@@ -39,16 +40,23 @@ void ide(const char *arg);
 
 void echo(const char *arg);
 
-void help(const char *arg);
+void help(const char *args);
+
+void shutdown(const char *args);
 
 cmd_handler cmd_handlers[] = {
-        {"help\0",  help},
-        {"echo\0",  echo},
-        {"print\0", print},
-        {"ide\0",   ide},
+        {"help\0",   help},
+        {"echo\0",   echo},
+        {"print\0",  print},
+        {"ide\0",    ide},
+        {"shutdown", shutdown},
         {NULL, NULL},
 };
 
+void shutdown(const char *args) {
+    power_shutdown();
+}
+
 void print_bootinfo() {
     printf("Bootloader name: %s\n"
            "cmdline: %s\n",
@@ -124,7 +132,7 @@ void store_bootloader_info(multiboot_info_t *multiboot_info) {
     }
 }
 
-void noreturn main_loop(void* data) {
+void noreturn main_loop(void *data) {
     while (true) {
         char *msg = readline(NULL);
         char *args = strchr(msg, ' ');