Kernel/LibC/DynamicLoader: Implement thread local storage

For some reason this does not work on 32 bit version, so it is disabled
on that platform. I'll have to look into it later to find the bug :)

userspace/libraries/LibC/unistd.cpp

@@ -1,10 +1,12 @@
 #include <BAN/Assert.h>
 #include <BAN/Debug.h>
+
 #include <kernel/Memory/Types.h>
 #include <kernel/Syscall.h>
 
 #include <errno.h>
 #include <fcntl.h>
+#include <pthread.h>
 #include <pwd.h>
 #include <stdarg.h>
 #include <stdio.h>
@@ -30,6 +32,21 @@ extern "C" void _init_libc(char** environ, init_funcs_t init_funcs, init_funcs_t
 	if (::environ == nullptr)
 		::environ = environ;
 
+	if (syscall(SYS_GET_TLS) == 0)
+	{
+		alignas(uthread) static uint8_t storage[sizeof(uthread) + sizeof(uintptr_t)];
+
+		uthread& uthread = *reinterpret_cast<struct uthread*>(storage);
+		uthread = {
+			.self = &uthread,
+			.master_tls_addr = nullptr,
+			.master_tls_size = 0,
+		};
+		uthread.dtv[0] = 0;
+
+		syscall(SYS_SET_TLS, &uthread);
+	}
+
 	// call global constructors
 	if (init_funcs.func)
 		init_funcs.func();