lib: Add mlibc

Signed-off-by: Ian Moffett <ian@osmora.org>

4 files changed, 2218 insertions, 0 deletions

diff --git a/lib/mlibc/sysdeps/linux/generic/cxx-syscall.hpp b/lib/mlibc/sysdeps/linux/generic/cxx-syscall.hpp
new file mode 100644
index 0000000..aa7d17c
--- /dev/null
+++ b/lib/mlibc/sysdeps/linux/generic/cxx-syscall.hpp
@@ -0,0 +1,118 @@
+#pragma once
+
+#include <errno.h>
+#include <mlibc/tcb.hpp>
+#include <mlibc/thread.hpp>
+#include <mlibc-config.h>
+#include <utility>
+
+#include <sys/syscall.h>
+#include <bits/syscall.h>
+
+using sc_word_t = __sc_word_t;
+
+extern "C" {
+	extern sc_word_t __mlibc_do_asm_cp_syscall(int sc, sc_word_t arg1, sc_word_t arg2,
+			sc_word_t arg3, sc_word_t arg4, sc_word_t arg5, sc_word_t arg6);
+
+	extern void __mlibc_do_cancel();
+}
+
+namespace mlibc {
+	// C++ wrappers for the extern "C" functions.
+	inline sc_word_t do_nargs_syscall(int sc) {
+		return __do_syscall0(sc);
+	}
+	inline sc_word_t do_nargs_syscall(int sc, sc_word_t arg1) {
+		return __do_syscall1(sc, arg1);
+	}
+	inline sc_word_t do_nargs_syscall(int sc, sc_word_t arg1, sc_word_t arg2) {
+		return __do_syscall2(sc, arg1, arg2);
+	}
+	inline sc_word_t do_nargs_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3) {
+		return __do_syscall3(sc, arg1, arg2, arg3);
+	}
+	inline sc_word_t do_nargs_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3,
+			sc_word_t arg4) {
+		return __do_syscall4(sc, arg1, arg2, arg3, arg4);
+	}
+	inline sc_word_t do_nargs_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3,
+			sc_word_t arg4, sc_word_t arg5) {
+		return __do_syscall5(sc, arg1, arg2, arg3, arg4, arg5);
+	}
+	inline sc_word_t do_nargs_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3,
+			sc_word_t arg4, sc_word_t arg5, sc_word_t arg6) {
+		return __do_syscall6(sc, arg1, arg2, arg3, arg4, arg5, arg6);
+	}
+
+	inline sc_word_t do_nargs_cp_syscall(int sc, sc_word_t arg1) {
+		return __mlibc_do_asm_cp_syscall(sc, arg1, 0, 0, 0, 0, 0);
+	}
+	inline sc_word_t do_nargs_cp_syscall(int sc, sc_word_t arg1, sc_word_t arg2) {
+		return __mlibc_do_asm_cp_syscall(sc, arg1, arg2, 0, 0, 0, 0);
+	}
+	inline sc_word_t do_nargs_cp_syscall(int sc, sc_word_t arg1, sc_word_t arg2,
+			sc_word_t arg3) {
+		return __mlibc_do_asm_cp_syscall(sc, arg1, arg2, arg3, 0, 0, 0);
+	}
+	inline sc_word_t do_nargs_cp_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3,
+			sc_word_t arg4) {
+		return __mlibc_do_asm_cp_syscall(sc, arg1, arg2, arg3, arg4, 0, 0);
+	}
+	inline sc_word_t do_nargs_cp_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3,
+			sc_word_t arg4, sc_word_t arg5) {
+		return __mlibc_do_asm_cp_syscall(sc, arg1, arg2, arg3, arg4, arg5, 0);
+	}
+	inline sc_word_t do_nargs_cp_syscall(int sc, sc_word_t arg1, sc_word_t arg2, sc_word_t arg3,
+			sc_word_t arg4, sc_word_t arg5, sc_word_t arg6) {
+		return __mlibc_do_asm_cp_syscall(sc, arg1, arg2, arg3, arg4, arg5, arg6);
+	}
+
+	// Type-safe syscall result type.
+	enum class sc_result_t : sc_word_t { };
+
+	// Cast to the argument type of the extern "C" functions.
+	inline sc_word_t sc_cast(long x) { return x; }
+	inline sc_word_t sc_cast(const void *x) { return reinterpret_cast<sc_word_t>(x); }
+
+	template<typename... T>
+	sc_result_t do_syscall(int sc, T... args) {
+		return static_cast<sc_result_t>(do_nargs_syscall(sc, sc_cast(args)...));
+	}
+
+	inline int sc_error(sc_result_t ret) {
+		auto v = static_cast<sc_word_t>(ret);
+		if(static_cast<unsigned long>(v) > -4096UL)
+			return -v;
+		return 0;
+	}
+
+	template<typename... T>
+	sc_result_t do_cp_syscall(int sc, T... args) {
+#if __MLIBC_POSIX_OPTION && !MLIBC_BUILDING_RTDL
+		auto result = static_cast<sc_result_t>(do_nargs_cp_syscall(sc, sc_cast(args)...));
+		if (int e = sc_error(result); e) {
+			auto tcb = reinterpret_cast<Tcb*>(get_current_tcb());
+			if (tcb_cancelled(tcb->cancelBits) && e == EINTR) {
+				__mlibc_do_cancel();
+				__builtin_unreachable();
+			}
+		}
+		return result;
+#else
+		return do_syscall(sc, std::forward<T>(args)...);
+#endif // __MLIBC_POSIX_OPTION || !MLIBC_BUILDING_RTDL
+	}
+	// Cast from the syscall result type.
+	template<typename T>
+	T sc_int_result(sc_result_t ret) {
+		auto v = static_cast<sc_word_t>(ret);
+		return v;
+	}
+
+	template<typename T>
+	T *sc_ptr_result(sc_result_t ret) {
+		auto v = static_cast<sc_word_t>(ret);
+		return reinterpret_cast<T *>(v);
+	}
+}
diff --git a/lib/mlibc/sysdeps/linux/generic/entry.cpp b/lib/mlibc/sysdeps/linux/generic/entry.cpp
new file mode 100644
index 0000000..aa049ce
--- /dev/null
+++ b/lib/mlibc/sysdeps/linux/generic/entry.cpp
@@ -0,0 +1,38 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <bits/ensure.h>
+#include <mlibc/elf/startup.h>
+#include <sys/auxv.h>
+
+// defined by the POSIX library
+void __mlibc_initLocale();
+
+extern "C" uintptr_t *__dlapi_entrystack();
+extern "C" void __dlapi_enter(uintptr_t *);
+
+extern char **environ;
+static mlibc::exec_stack_data __mlibc_stack_data;
+
+size_t __hwcap;
+
+struct LibraryGuard {
+	LibraryGuard();
+};
+
+static LibraryGuard guard;
+
+LibraryGuard::LibraryGuard() {
+	__mlibc_initLocale();
+
+	// Parse the exec() stack.
+	mlibc::parse_exec_stack(__dlapi_entrystack(), &__mlibc_stack_data);
+	mlibc::set_startup_data(__mlibc_stack_data.argc, __mlibc_stack_data.argv,
+			__mlibc_stack_data.envp);
+}
+
+extern "C" void __mlibc_entry(uintptr_t *entry_stack, int (*main_fn)(int argc, char *argv[], char *env[])) {
+	__dlapi_enter(entry_stack);
+	__hwcap = getauxval(AT_HWCAP);
+	auto result = main_fn(__mlibc_stack_data.argc, __mlibc_stack_data.argv, environ);
+	exit(result);
+}
diff --git a/lib/mlibc/sysdeps/linux/generic/sysdeps.cpp b/lib/mlibc/sysdeps/linux/generic/sysdeps.cpp
new file mode 100644
index 0000000..bc33a9e
--- /dev/null
+++ b/lib/mlibc/sysdeps/linux/generic/sysdeps.cpp
@@ -0,0 +1,2002 @@
+#include <asm/ioctls.h>
+#include <errno.h>
+#include <limits.h>
+
+#include <type_traits>
+
+#include <mlibc-config.h>
+#include <bits/ensure.h>
+#include <abi-bits/fcntl.h>
+#include <abi-bits/socklen_t.h>
+#include <mlibc/allocator.hpp>
+#include <mlibc/debug.hpp>
+#include <mlibc/all-sysdeps.hpp>
+#include <mlibc/thread-entry.hpp>
+#include <limits.h>
+#include <sys/syscall.h>
+#include "cxx-syscall.hpp"
+
+#define STUB_ONLY { __ensure(!"STUB_ONLY function was called"); __builtin_unreachable(); }
+#define UNUSED(x) (void)(x);
+
+#ifndef MLIBC_BUILDING_RTDL
+extern "C" long __do_syscall_ret(unsigned long ret) {
+	if(ret > -4096UL) {
+		errno = -ret;
+		return -1;
+	}
+	return ret;
+}
+#endif
+
+namespace mlibc {
+
+void sys_libc_log(const char *message) {
+	size_t n = 0;
+	while(message[n])
+		n++;
+	do_syscall(SYS_write, 2, message, n);
+	char lf = '\n';
+	do_syscall(SYS_write, 2, &lf, 1);
+}
+
+void sys_libc_panic() {
+	__builtin_trap();
+}
+
+#if defined(__i386__)
+
+struct user_desc {
+	unsigned int entry_number;
+	unsigned long base_addr;
+	unsigned int limit;
+	unsigned int seg_32bit: 1;
+	unsigned int contents: 2;
+	unsigned int read_exec_only: 1;
+	unsigned int limit_in_pages: 1;
+	unsigned int seg_not_present: 1;
+	unsigned int useable: 1;
+};
+
+#endif
+
+int sys_tcb_set(void *pointer) {
+#if defined(__x86_64__)
+	auto ret = do_syscall(SYS_arch_prctl, 0x1002 /* ARCH_SET_FS */, pointer);
+	if(int e = sc_error(ret); e)
+		return e;
+#elif defined(__i386__)
+	struct user_desc desc = {
+		.entry_number = static_cast<unsigned int>(-1),
+		.base_addr = uintptr_t(pointer),
+		.limit = 0xfffff,
+		.seg_32bit = 1,
+		.contents = 0,
+		.read_exec_only = 0,
+		.limit_in_pages = 1,
+		.seg_not_present = 0,
+		.useable = 1,
+	};
+	auto ret = do_syscall(SYS_set_thread_area, &desc);
+	__ensure(!sc_error(ret));
+	asm volatile ("movw %w0, %%gs" : : "q"(desc.entry_number * 8 + 3) :);
+#elif defined(__riscv)
+	uintptr_t thread_data = reinterpret_cast<uintptr_t>(pointer) + sizeof(Tcb);
+	asm volatile ("mv tp, %0" :: "r"(thread_data));
+#elif defined (__aarch64__)
+	uintptr_t thread_data = reinterpret_cast<uintptr_t>(pointer) + sizeof(Tcb) - 0x10;
+	asm volatile ("msr tpidr_el0, %0" :: "r"(thread_data));
+#else
+#error "Missing architecture specific code."
+#endif
+	return 0;
+}
+
+int sys_anon_allocate(size_t size, void **pointer) {
+	return sys_vm_map(nullptr, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS,
+			-1, 0, pointer);
+}
+int sys_anon_free(void *pointer, size_t size) {
+	return sys_vm_unmap(pointer, size);
+}
+
+int sys_fadvise(int fd, off_t offset, off_t length, int advice) {
+	auto ret = do_syscall(SYS_fadvise64, fd, offset, length, advice);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_open(const char *path, int flags, mode_t mode, int *fd) {
+	auto ret = do_cp_syscall(SYS_openat, AT_FDCWD, path, flags, mode);
+	if(int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_openat(int dirfd, const char *path, int flags, mode_t mode, int *fd) {
+	auto ret = do_syscall(SYS_openat, dirfd, path, flags, mode);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_close(int fd) {
+	auto ret = do_cp_syscall(SYS_close, fd);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_dup2(int fd, int flags, int newfd) {
+	auto ret = do_cp_syscall(SYS_dup3, fd, newfd, flags);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_read(int fd, void *buffer, size_t size, ssize_t *bytes_read) {
+	auto ret = do_cp_syscall(SYS_read, fd, buffer, size);
+	if(int e = sc_error(ret); e)
+		return e;
+	*bytes_read = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_readv(int fd, const struct iovec *iovs, int iovc, ssize_t *bytes_read) {
+	auto ret = do_cp_syscall(SYS_readv, fd, iovs, iovc);
+	if(int e = sc_error(ret); e)
+		return e;
+	*bytes_read = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_write(int fd, const void *buffer, size_t size, ssize_t *bytes_written) {
+	auto ret = do_cp_syscall(SYS_write, fd, buffer, size);
+	if(int e = sc_error(ret); e)
+		return e;
+	if(bytes_written)
+		*bytes_written = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_seek(int fd, off_t offset, int whence, off_t *new_offset) {
+	auto ret = do_syscall(SYS_lseek, fd, offset, whence);
+	if(int e = sc_error(ret); e)
+		return e;
+	*new_offset = sc_int_result<off_t>(ret);
+	return 0;
+}
+
+int sys_chmod(const char *pathname, mode_t mode) {
+	auto ret = do_cp_syscall(SYS_fchmodat, AT_FDCWD, pathname, mode);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_fchmod(int fd, mode_t mode) {
+	auto ret = do_cp_syscall(SYS_fchmod, fd, mode);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_fchmodat(int fd, const char *pathname, mode_t mode, int flags) {
+	auto ret = do_cp_syscall(SYS_fchmodat, fd, pathname, mode, flags);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_fchownat(int dirfd, const char *pathname, uid_t owner, gid_t group, int flags) {
+	auto ret = do_cp_syscall(SYS_fchownat, dirfd, pathname, owner, group, flags);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_utimensat(int dirfd, const char *pathname, const struct timespec times[2], int flags) {
+	auto ret = do_cp_syscall(SYS_utimensat, dirfd, pathname, times, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_vm_map(void *hint, size_t size, int prot, int flags,
+		int fd, off_t offset, void **window) {
+	if(offset % 4096)
+		return EINVAL;
+	if(size >= PTRDIFF_MAX)
+		return ENOMEM;
+#if defined(SYS_mmap2)
+	auto ret = do_syscall(SYS_mmap2, hint, size, prot, flags, fd, offset/4096);
+#else
+	auto ret = do_syscall(SYS_mmap, hint, size, prot, flags, fd, offset);
+#endif
+	// TODO: musl fixes up EPERM errors from the kernel.
+	if(int e = sc_error(ret); e)
+		return e;
+	*window = sc_ptr_result<void>(ret);
+	return 0;
+}
+
+int sys_vm_unmap(void *pointer, size_t size) {
+	auto ret = do_syscall(SYS_munmap, pointer, size);
+	if(int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+// All remaining functions are disabled in ldso.
+#ifndef MLIBC_BUILDING_RTDL
+
+int sys_clock_get(int clock, time_t *secs, long *nanos) {
+	struct timespec tp = {};
+	auto ret = do_syscall(SYS_clock_gettime, clock, &tp);
+	if (int e = sc_error(ret); e)
+		return e;
+	*secs = tp.tv_sec;
+	*nanos = tp.tv_nsec;
+	return 0;
+}
+
+int sys_clock_getres(int clock, time_t *secs, long *nanos) {
+	struct timespec tp = {};
+	auto ret = do_syscall(SYS_clock_getres, clock, &tp);
+	if (int e = sc_error(ret); e)
+		return e;
+	*secs = tp.tv_sec;
+	*nanos = tp.tv_nsec;
+	return 0;
+}
+
+int sys_stat(fsfd_target fsfdt, int fd, const char *path, int flags, struct stat *statbuf) {
+	if (fsfdt == fsfd_target::path)
+		fd = AT_FDCWD;
+	else if (fsfdt == fsfd_target::fd)
+		flags |= AT_EMPTY_PATH;
+	else
+		__ensure(fsfdt == fsfd_target::fd_path);
+
+#if defined(SYS_newfstatat)
+	auto ret = do_cp_syscall(SYS_newfstatat, fd, path, statbuf, flags);
+#else
+	auto ret = do_cp_syscall(SYS_fstatat64, fd, path, statbuf, flags);
+#endif
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_statfs(const char *path, struct statfs *buf) {
+	auto ret = do_cp_syscall(SYS_statfs, path, buf);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_fstatfs(int fd, struct statfs *buf) {
+	auto ret = do_cp_syscall(SYS_fstatfs, fd, buf);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+extern "C" void __mlibc_signal_restore(void);
+extern "C" void __mlibc_signal_restore_rt(void);
+
+int sys_sigaction(int signum, const struct sigaction *act,
+                struct sigaction *oldact) {
+	struct ksigaction {
+		void (*handler)(int);
+		unsigned long flags;
+		void (*restorer)(void);
+		sigset_t mask;
+	};
+
+	struct ksigaction kernel_act, kernel_oldact;
+	if (act) {
+		kernel_act.handler = act->sa_handler;
+		kernel_act.flags = act->sa_flags | SA_RESTORER;
+		kernel_act.restorer = (act->sa_flags & SA_SIGINFO) ? __mlibc_signal_restore_rt : __mlibc_signal_restore;
+		kernel_act.mask = act->sa_mask;
+	}
+
+	static_assert(sizeof(sigset_t) == 8);
+
+        auto ret = do_syscall(SYS_rt_sigaction, signum, act ?
+			&kernel_act : NULL, oldact ?
+			&kernel_oldact : NULL, sizeof(sigset_t));
+        if (int e = sc_error(ret); e)
+                return e;
+
+	if (oldact) {
+		oldact->sa_handler = kernel_oldact.handler;
+		oldact->sa_flags = kernel_oldact.flags;
+		oldact->sa_restorer = kernel_oldact.restorer;
+		oldact->sa_mask = kernel_oldact.mask;
+	}
+        return 0;
+}
+
+int sys_socket(int domain, int type, int protocol, int *fd) {
+        auto ret = do_syscall(SYS_socket, domain, type, protocol);
+        if (int e = sc_error(ret); e)
+                return e;
+        *fd = sc_int_result<int>(ret);
+        return 0;
+}
+
+int sys_msg_send(int sockfd, const struct msghdr *msg, int flags, ssize_t *length) {
+        auto ret = do_cp_syscall(SYS_sendmsg, sockfd, msg, flags);
+        if (int e = sc_error(ret); e)
+                return e;
+        *length = sc_int_result<ssize_t>(ret);
+        return 0;
+}
+
+ssize_t sys_sendto(int fd, const void *buffer, size_t size, int flags, const struct sockaddr *sock_addr, socklen_t addr_length, ssize_t *length) {
+	auto ret = do_cp_syscall(SYS_sendto, fd, buffer, size, flags, sock_addr, addr_length);
+	if(int e = sc_error(ret); e) {
+		return e;
+	}
+	*length = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+ssize_t sys_recvfrom(int fd, void *buffer, size_t size, int flags, struct sockaddr *sock_addr, socklen_t *addr_length, ssize_t *length) {
+	auto ret = do_cp_syscall(SYS_recvfrom, fd, buffer, size, flags, sock_addr, addr_length);
+	if(int e = sc_error(ret); e) {
+		return e;
+	}
+	*length = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_msg_recv(int sockfd, struct msghdr *msg, int flags, ssize_t *length) {
+        auto ret = do_cp_syscall(SYS_recvmsg, sockfd, msg, flags);
+        if (int e = sc_error(ret); e)
+                return e;
+        *length = sc_int_result<ssize_t>(ret);
+        return 0;
+}
+
+int sys_fcntl(int fd, int cmd, va_list args, int *result) {
+        auto arg = va_arg(args, unsigned long);
+        // TODO: the api for linux differs for each command so fcntl()s might fail with -EINVAL
+        // we should implement all the different fcntl()s
+	// TODO(geert): only some fcntl()s can fail with -EINTR, making do_cp_syscall useless
+	// on most fcntls(). Another reason to handle different fcntl()s seperately.
+        auto ret = do_cp_syscall(SYS_fcntl, fd, cmd, arg);
+        if (int e = sc_error(ret); e)
+                return e;
+        *result = sc_int_result<int>(ret);
+        return 0;
+}
+
+int sys_getcwd(char *buf, size_t size) {
+	auto ret = do_syscall(SYS_getcwd, buf, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+	return 0;
+}
+
+int sys_unlinkat(int dfd, const char *path, int flags) {
+	auto ret = do_syscall(SYS_unlinkat, dfd, path, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_sleep(time_t *secs, long *nanos) {
+	struct timespec req = {
+		.tv_sec = *secs,
+		.tv_nsec = *nanos
+	};
+	struct timespec rem = {};
+
+	auto ret = do_cp_syscall(SYS_nanosleep, &req, &rem);
+        if (int e = sc_error(ret); e)
+                return e;
+
+	*secs = rem.tv_sec;
+	*nanos = rem.tv_nsec;
+	return 0;
+}
+
+int sys_isatty(int fd) {
+	unsigned short winsizeHack[4];
+	auto ret = do_syscall(SYS_ioctl, fd, 0x5413 /* TIOCGWINSZ */, &winsizeHack);
+	if (int e = sc_error(ret); e)
+		return e;
+	auto res = sc_int_result<unsigned long>(ret);
+	if(!res) return 0;
+	return 1;
+}
+
+#if __MLIBC_POSIX_OPTION
+
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <sys/ipc.h>
+#include <sys/user.h>
+#include <sys/utsname.h>
+#include <sys/stat.h>
+#include <sys/sysinfo.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <fcntl.h>
+#include <pthread.h>
+
+int sys_ioctl(int fd, unsigned long request, void *arg, int *result) {
+	auto ret = do_syscall(SYS_ioctl, fd, request, arg);
+	if (int e = sc_error(ret); e)
+		return e;
+	if (result)
+		*result = sc_int_result<unsigned long>(ret);
+	return 0;
+}
+
+int sys_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen) {
+        auto ret = do_cp_syscall(SYS_connect, sockfd, addr, addrlen);
+        if (int e = sc_error(ret); e)
+                return e;
+        return 0;
+}
+
+int sys_pselect(int nfds, fd_set *readfds, fd_set *writefds,
+                fd_set *exceptfds, const struct timespec *timeout, const sigset_t *sigmask, int *num_events) {
+        // The Linux kernel really wants 7 arguments, even tho this is not supported
+        // To fix that issue, they use a struct as the last argument.
+        // See the man page of pselect and the glibc source code
+        struct {
+                sigset_t ss;
+                size_t ss_len;
+        } data;
+        data.ss = (uintptr_t)sigmask;
+        data.ss_len = NSIG / 8;
+
+        auto ret = do_cp_syscall(SYS_pselect6, nfds, readfds, writefds,
+                        exceptfds, timeout, &data);
+        if (int e = sc_error(ret); e)
+                return e;
+        *num_events = sc_int_result<int>(ret);
+        return 0;
+}
+
+int sys_pipe(int *fds, int flags) {
+        if(flags) {
+                auto ret = do_syscall(SYS_pipe2, fds, flags);
+                if (int e = sc_error(ret); e)
+                        return e;
+                return 0;
+        } else {
+				auto ret = do_syscall(SYS_pipe2, fds, 0);
+                if (int e = sc_error(ret); e)
+                        return e;
+                return 0;
+        }
+}
+
+int sys_fork(pid_t *child) {
+	auto ret = do_syscall(SYS_clone, SIGCHLD, 0);
+	if (int e = sc_error(ret); e)
+			return e;
+	*child = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_waitpid(pid_t pid, int *status, int flags, struct rusage *ru, pid_t *ret_pid) {
+	auto ret = do_syscall(SYS_wait4, pid, status, flags, ru);
+	if (int e = sc_error(ret); e)
+			return e;
+	*ret_pid = sc_int_result<pid_t>(ret);
+	return 0;
+}
+
+int sys_execve(const char *path, char *const argv[], char *const envp[]) {
+        auto ret = do_syscall(SYS_execve, path, argv, envp);
+        if (int e = sc_error(ret); e)
+                return e;
+        return 0;
+}
+
+int sys_sigprocmask(int how, const sigset_t *set, sigset_t *old) {
+        auto ret = do_syscall(SYS_rt_sigprocmask, how, set, old, NSIG / 8);
+        if (int e = sc_error(ret); e)
+                return e;
+	return 0;
+}
+
+int sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) {
+	auto ret = do_syscall(SYS_setresuid, ruid, euid, suid);
+        if (int e = sc_error(ret); e)
+                return e;
+	return 0;
+}
+
+int sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) {
+	auto ret = do_syscall(SYS_setresgid, rgid, egid, sgid);
+        if (int e = sc_error(ret); e)
+                return e;
+	return 0;
+}
+
+int sys_getresuid(uid_t *ruid, uid_t *euid, uid_t *suid) {
+	auto ret = do_syscall(SYS_getresuid, &ruid, &euid, &suid);
+        if (int e = sc_error(ret); e)
+                return e;
+	return 0;
+}
+
+int sys_getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid) {
+	auto ret = do_syscall(SYS_getresgid, &rgid, &egid, &sgid);
+        if (int e = sc_error(ret); e)
+                return e;
+	return 0;
+}
+
+int sys_setreuid(uid_t ruid, uid_t euid) {
+	auto ret = do_syscall(SYS_setreuid, ruid, euid);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_setregid(gid_t rgid, gid_t egid) {
+	auto ret = do_syscall(SYS_setregid, rgid, egid);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_sysinfo(struct sysinfo *info) {
+	auto ret = do_syscall(SYS_sysinfo, info);
+        if (int e = sc_error(ret); e)
+                return e;
+	return 0;
+}
+
+void sys_yield() {
+	do_syscall(SYS_sched_yield);
+}
+
+int sys_clone(void *tcb, pid_t *pid_out, void *stack) {
+	unsigned long flags = CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND
+		| CLONE_THREAD | CLONE_SYSVSEM | CLONE_SETTLS
+		| CLONE_PARENT_SETTID;
+
+#if defined(__riscv)
+	// TP should point to the address immediately after the TCB.
+	// TODO: We should change the sysdep so that we don't need to do this.
+	auto tls = reinterpret_cast<char *>(tcb) + sizeof(Tcb);
+	tcb = reinterpret_cast<void *>(tls);
+#elif defined(__aarch64__)
+	// TP should point to the address 16 bytes before the end of the TCB.
+	// TODO: We should change the sysdep so that we don't need to do this.
+	auto tp = reinterpret_cast<char *>(tcb) + sizeof(Tcb) - 0x10;
+	tcb = reinterpret_cast<void *>(tp);
+#elif defined(__i386__)
+	/* get the entry number, as we don't request a new one here */
+	uint32_t gs;
+	asm volatile("movw %%gs, %w0" : "=q"(gs));
+
+	auto user_desc = reinterpret_cast<struct user_desc *>(getAllocator().allocate(sizeof(struct user_desc)));
+
+	user_desc->entry_number = (gs & 0xffff) >> 3;
+	user_desc->base_addr = uintptr_t(tcb);
+	user_desc->limit = 0xfffff;
+	user_desc->seg_32bit = 1;
+	user_desc->contents = 0;
+	user_desc->read_exec_only = 0;
+	user_desc->limit_in_pages = 1;
+	user_desc->seg_not_present = 0;
+	user_desc->useable = 1;
+
+	tcb = reinterpret_cast<void *>(user_desc);
+#endif
+
+	auto ret = __mlibc_spawn_thread(flags, stack, pid_out, NULL, tcb);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+extern "C" const char __mlibc_syscall_begin[1];
+extern "C" const char __mlibc_syscall_end[1];
+
+#if defined(__riscv)
+// Disable UBSan here to work around qemu-user misaligning ucontext_t.
+// https://github.com/qemu/qemu/blob/2bf40d0841b942e7ba12953d515e62a436f0af84/linux-user/riscv/signal.c#L68-L69
+[[gnu::no_sanitize("undefined")]]
+#endif
+int sys_before_cancellable_syscall(ucontext_t *uct) {
+#if defined(__x86_64__)
+	auto pc = reinterpret_cast<void*>(uct->uc_mcontext.gregs[REG_RIP]);
+#elif defined(__i386__)
+	auto pc = reinterpret_cast<void*>(uct->uc_mcontext.gregs[REG_EIP]);
+#elif defined(__riscv)
+	auto pc = reinterpret_cast<void*>(uct->uc_mcontext.gregs[REG_PC]);
+#elif defined(__aarch64__)
+	auto pc = reinterpret_cast<void*>(uct->uc_mcontext.pc);
+#else
+#error "Missing architecture specific code."
+#endif
+	if (pc < __mlibc_syscall_begin || pc > __mlibc_syscall_end)
+		return 0;
+	return 1;
+}
+
+int sys_tgkill(int tgid, int tid, int sig) {
+	auto ret = do_syscall(SYS_tgkill, tgid, tid, sig);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_tcgetattr(int fd, struct termios *attr) {
+	auto ret = do_syscall(SYS_ioctl, fd, TCGETS, attr);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_tcsetattr(int fd, int optional_action, const struct termios *attr) {
+	int req;
+
+	switch (optional_action) {
+		case TCSANOW: req = TCSETS; break;
+		case TCSADRAIN: req = TCSETSW; break;
+		case TCSAFLUSH: req = TCSETSF; break;
+		default: return EINVAL;
+	}
+
+	auto ret = do_syscall(SYS_ioctl, fd, req, attr);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_tcflush(int fd, int queue) {
+	auto ret = do_syscall(SYS_ioctl, fd, TCFLSH, queue);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_tcdrain(int fd) {
+	auto ret = do_syscall(SYS_ioctl, fd, TCSBRK, 1);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_tcflow(int fd, int action) {
+	auto ret = do_syscall(SYS_ioctl, fd, TCXONC, action);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_access(const char *path, int mode) {
+	auto ret = do_syscall(SYS_faccessat, AT_FDCWD, path, mode, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_faccessat(int dirfd, const char *pathname, int mode, int flags) {
+	auto ret = do_syscall(SYS_faccessat, dirfd, pathname, mode, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_accept(int fd, int *newfd, struct sockaddr *addr_ptr, socklen_t *addr_length, int flags) {
+	auto ret = do_syscall(SYS_accept4, fd, addr_ptr, addr_length, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*newfd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_bind(int fd, const struct sockaddr *addr_ptr, socklen_t addr_length) {
+	auto ret = do_syscall(SYS_bind, fd, addr_ptr, addr_length, 0, 0, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_setsockopt(int fd, int layer, int number, const void *buffer, socklen_t size) {
+	auto ret = do_syscall(SYS_setsockopt, fd, layer, number, buffer, size, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_sockname(int fd, struct sockaddr *addr_ptr, socklen_t max_addr_length,
+		socklen_t *actual_length) {
+	auto ret = do_syscall(SYS_getsockname, fd, addr_ptr, &max_addr_length);
+	if (int e = sc_error(ret); e)
+		return e;
+	*actual_length = max_addr_length;
+	return 0;
+}
+
+int sys_peername(int fd, struct sockaddr *addr_ptr, socklen_t max_addr_length,
+		socklen_t *actual_length) {
+	auto ret = do_syscall(SYS_getpeername, fd, addr_ptr, &max_addr_length);
+	if (int e = sc_error(ret); e)
+		return e;
+	*actual_length = max_addr_length;
+	return 0;
+}
+
+int sys_listen(int fd, int backlog) {
+	auto ret = do_syscall(SYS_listen, fd, backlog, 0, 0, 0, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_shutdown(int sockfd, int how) {
+	auto ret = do_syscall(SYS_shutdown, sockfd, how);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+	return 0;
+}
+
+int sys_getpriority(int which, id_t who, int *value) {
+	auto ret = do_syscall(SYS_getpriority, which, who);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+	*value = 20 - sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_setpriority(int which, id_t who, int prio) {
+	auto ret = do_syscall(SYS_setpriority, which, who, prio);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_setitimer(int which, const struct itimerval *new_value, struct itimerval *old_value) {
+	auto ret = do_syscall(SYS_setitimer, which, new_value, old_value);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+/* Linux' uapi does some weird union stuff in place of `sigev_tid`, which we conveniently ignore */
+struct linux_uapi_sigevent {
+	union sigval sigev_value;
+	int sigev_signo;
+	int sigev_notify;
+	int sigev_tid;
+};
+
+int sys_timer_create(clockid_t clk, struct sigevent *__restrict evp, timer_t *__restrict res) {
+	struct linux_uapi_sigevent ksev;
+	struct linux_uapi_sigevent *ksevp = 0;
+	int timer_id;
+
+	switch(evp ? evp->sigev_notify : SIGEV_SIGNAL) {
+		case SIGEV_NONE:
+		case SIGEV_SIGNAL: {
+			if(evp) {
+				ksev.sigev_value = evp->sigev_value;
+				ksev.sigev_signo = evp->sigev_signo;
+				ksev.sigev_notify = evp->sigev_notify;
+				ksev.sigev_tid = 0;
+				ksevp = &ksev;
+			}
+
+			auto ret = do_syscall(SYS_timer_create, clk, ksevp, &timer_id);
+			if (int e = sc_error(ret); e) {
+				return e;
+			}
+			*res = (void *) (intptr_t) timer_id;
+			break;
+		}
+		case SIGEV_THREAD:
+			__ensure(!"sys_timer_create with evp->sigev_notify == SIGEV_THREAD is unimplemented");
+			[[fallthrough]];
+		default:
+			return EINVAL;
+	}
+
+	return 0;
+}
+
+int sys_timer_settime(timer_t t, int flags, const struct itimerspec *__restrict val, struct itimerspec *__restrict old) {
+	auto ret = do_syscall(SYS_timer_settime, t, flags, val, old);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+	return 0;
+}
+
+int sys_timer_delete(timer_t t) {
+	__ensure((intptr_t) t >= 0);
+	auto ret = do_syscall(SYS_timer_delete, t);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+	return 0;
+}
+
+int sys_ptrace(long req, pid_t pid, void *addr, void *data, long *out) {
+	auto ret = do_syscall(SYS_ptrace, req, pid, addr, data);
+	if (int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<long>(ret);
+	return 0;
+}
+
+int sys_open_dir(const char *path, int *fd) {
+	return sys_open(path, O_DIRECTORY, 0, fd);
+}
+
+int sys_read_entries(int handle, void *buffer, size_t max_size, size_t *bytes_read) {
+	auto ret = do_syscall(SYS_getdents64, handle, buffer, max_size);
+	if(int e = sc_error(ret); e)
+		return e;
+	*bytes_read = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_prctl(int op, va_list ap, int *out) {
+	unsigned long x[4];
+	for(int i = 0; i < 4; i++)
+		x[i] = va_arg(ap, unsigned long);
+
+	auto ret = do_syscall(SYS_prctl, op, x[0], x[1], x[2], x[3]);
+	if (int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_uname(struct utsname *buf) {
+	auto ret = do_syscall(SYS_uname, buf);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_gethostname(char *buf, size_t bufsize) {
+	struct utsname uname_buf;
+	if (auto e = sys_uname(&uname_buf); e)
+		return e;
+
+	auto node_len = strlen(uname_buf.nodename);
+	if (node_len >= bufsize)
+		return ENAMETOOLONG;
+
+	memcpy(buf, uname_buf.nodename, node_len);
+	buf[node_len] = '\0';
+	return 0;
+}
+
+int sys_pread(int fd, void *buf, size_t n, off_t off, ssize_t *bytes_read) {
+	auto ret = do_syscall(SYS_pread64, fd, buf, n, off);
+	if (int e = sc_error(ret); e)
+		return e;
+	*bytes_read = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_pwrite(int fd, const void *buf, size_t n, off_t off, ssize_t *bytes_written) {
+	auto ret = do_syscall(SYS_pwrite64, fd, buf, n, off);
+	if (int e = sc_error(ret); e)
+		return e;
+	*bytes_written = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_poll(struct pollfd *fds, nfds_t count, int timeout, int *num_events) {
+	struct timespec tm;
+	tm.tv_sec = timeout / 1000;
+	tm.tv_nsec = timeout % 1000 * 1000000;
+	auto ret = do_syscall(SYS_ppoll, fds, count, timeout >= 0 ? &tm : nullptr, 0, NSIG / 8);
+	if (int e = sc_error(ret); e)
+		return e;
+	*num_events = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_getrusage(int scope, struct rusage *usage) {
+	auto ret = do_syscall(SYS_getrusage, scope, usage);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_madvise(void *addr, size_t length, int advice) {
+	auto ret = do_syscall(SYS_madvise, addr, length, advice);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_msync(void *addr, size_t length, int flags) {
+	auto ret = do_syscall(SYS_msync, addr, length, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_swapon(const char *path, int flags) {
+	auto ret = do_syscall(SYS_swapon, path, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_swapoff(const char *path) {
+	auto ret = do_syscall(SYS_swapoff, path);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_getaffinity(pid_t pid, size_t cpusetsize, cpu_set_t *mask) {
+	auto ret = do_syscall(SYS_sched_getaffinity, pid, cpusetsize, mask);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_mount(const char *source, const char *target,
+	const char *fstype, unsigned long flags, const void *data) {
+	auto ret = do_syscall(SYS_mount, source, target, fstype, flags, data);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_umount2(const char *target, int flags) {
+	auto ret = do_syscall(SYS_umount2, target, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_sethostname(const char *buffer, size_t bufsize) {
+	auto ret = do_syscall(SYS_sethostname, buffer, bufsize);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_epoll_create(int flags, int *fd) {
+	auto ret = do_syscall(SYS_epoll_create1, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_epoll_ctl(int epfd, int mode, int fd, struct epoll_event *ev) {
+	auto ret = do_syscall(SYS_epoll_ctl, epfd, mode, fd, ev);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_epoll_pwait(int epfd, struct epoll_event *ev, int n, int timeout, const sigset_t *sigmask, int *raised) {
+	auto ret = do_syscall(SYS_epoll_pwait, epfd, ev, n, timeout, sigmask, NSIG / 8);
+	if (int e = sc_error(ret); e)
+		return e;
+	*raised = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_eventfd_create(unsigned int initval, int flags, int *fd) {
+	auto ret = do_syscall(SYS_eventfd2, initval, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_signalfd_create(const sigset_t *masks, int flags, int *fd) {
+	auto ret = do_syscall(SYS_signalfd4, *fd, masks, sizeof(sigset_t), flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_timerfd_create(int clockid, int flags, int *fd) {
+	auto ret = do_syscall(SYS_timerfd_create, clockid, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_timerfd_settime(int fd, int flags, const struct itimerspec *value, struct itimerspec *oldvalue) {
+	auto ret = do_syscall(SYS_timerfd_settime, fd, flags, value, oldvalue);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_inotify_create(int flags, int *fd) {
+	auto ret = do_syscall(SYS_inotify_init1, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_init_module(void *module, unsigned long length, const char *args) {
+	auto ret = do_syscall(SYS_init_module, module, length, args);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_delete_module(const char *name, unsigned flags) {
+	auto ret = do_syscall(SYS_delete_module, name, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_klogctl(int type, char *bufp, int len, int *out) {
+	auto ret = do_syscall(SYS_syslog, type, bufp, len);
+	if (int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_getcpu(int *cpu) {
+	auto ret = do_syscall(SYS_getcpu, cpu, NULL, NULL);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_socketpair(int domain, int type_and_flags, int proto, int *fds) {
+	auto ret = do_syscall(SYS_socketpair, domain, type_and_flags, proto, fds, 0, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_getsockopt(int fd, int layer, int number, void *__restrict buffer, socklen_t *__restrict size) {
+	auto ret = do_syscall(SYS_getsockopt, fd, layer, number, buffer, size, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_inotify_add_watch(int ifd, const char *path, uint32_t mask, int *wd) {
+	auto ret = do_syscall(SYS_inotify_add_watch, ifd, path, mask);
+	if (int e = sc_error(ret); e)
+		return e;
+	*wd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_inotify_rm_watch(int ifd, int wd) {
+	auto ret = do_syscall(SYS_inotify_rm_watch, ifd, wd);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_ttyname(int fd, char *buf, size_t size) {
+	if (!isatty(fd))
+		return errno;
+
+	char *procname;
+	if(int e = asprintf(&procname, "/proc/self/fd/%i", fd); e)
+		return ENOMEM;
+	__ensure(procname);
+
+	ssize_t l = readlink(procname, buf, size);
+	free(procname);
+
+	if (l < 0)
+		return errno;
+	else if ((size_t)l >= size)
+		return ERANGE;
+
+	buf[l] = '\0';
+	struct stat st1;
+	struct stat st2;
+
+	if (stat(buf, &st1) || fstat(fd, &st2))
+		return errno;
+	if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
+		return ENODEV;
+
+	return 0;
+}
+
+int sys_pause() {
+#ifdef SYS_pause
+	auto ret = do_syscall(SYS_pause);
+#else
+	auto ret = do_syscall(SYS_ppoll, 0, 0, 0, 0);
+#endif
+	if (int e = sc_error(ret); e)
+		return e;
+	return EINTR;
+}
+
+int sys_mlockall(int flags) {
+	auto ret = do_syscall(SYS_mlockall, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_get_min_priority(int policy, int *out) {
+	auto ret = do_syscall(SYS_sched_get_priority_min, policy);
+	if (int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<int>(ret);
+
+	return 0;
+}
+
+int sys_getschedparam(void *tcb, int *policy, struct sched_param *param) {
+	auto t = reinterpret_cast<Tcb *>(tcb);
+
+	if(!t->tid) {
+		return ESRCH;
+	}
+
+	auto ret_param = do_syscall(SYS_sched_getparam, t->tid, param);
+	if (int e = sc_error(ret_param); e)
+		return e;
+
+	auto ret_sched = do_syscall(SYS_sched_getscheduler, t->tid, param);
+	if (int e = sc_error(ret_sched); e)
+		return e;
+	*policy = sc_int_result<int>(ret_sched);
+
+	return 0;
+}
+
+int sys_setschedparam(void *tcb, int policy, const struct sched_param *param) {
+	auto t = reinterpret_cast<Tcb *>(tcb);
+
+	if(!t->tid) {
+		return ESRCH;
+	}
+
+	auto ret = do_syscall(SYS_sched_setscheduler, t->tid, policy, param);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_if_indextoname(unsigned int index, char *name) {
+	int fd = 0;
+	int r = sys_socket(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, AF_UNSPEC, &fd);
+
+	if(r)
+		return r;
+
+	struct ifreq ifr;
+	ifr.ifr_ifindex = index;
+
+	int ret = sys_ioctl(fd, SIOCGIFNAME, &ifr, NULL);
+	close(fd);
+
+	if(ret) {
+		if(ret == ENODEV)
+			return ENXIO;
+		return ret;
+	}
+
+	strncpy(name, ifr.ifr_name, IF_NAMESIZE);
+
+	return 0;
+}
+
+int sys_if_nametoindex(const char *name, unsigned int *ret) {
+	int fd = 0;
+	int r = sys_socket(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, AF_UNSPEC, &fd);
+
+	if(r)
+		return r;
+
+	struct ifreq ifr;
+	strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+
+	r = sys_ioctl(fd, SIOCGIFINDEX, &ifr, NULL);
+	close(fd);
+
+	if(r) {
+		return r;
+	}
+
+	*ret = ifr.ifr_ifindex;
+
+	return 0;
+}
+
+int sys_ptsname(int fd, char *buffer, size_t length) {
+	int index;
+	if(int e = sys_ioctl(fd, TIOCGPTN, &index, NULL); e)
+		return e;
+	if((size_t)snprintf(buffer, length, "/dev/pts/%d", index) >= length) {
+		return ERANGE;
+	}
+	return 0;
+}
+
+int sys_unlockpt(int fd) {
+	int unlock = 0;
+
+	if(int e = sys_ioctl(fd, TIOCSPTLCK, &unlock, NULL); e)
+		return e;
+
+	return 0;
+}
+
+int sys_thread_setname(void *tcb, const char *name) {
+	if(strlen(name) > 15) {
+		return ERANGE;
+	}
+
+	auto t = reinterpret_cast<Tcb *>(tcb);
+	char *path;
+	int cs = 0;
+
+	if(asprintf(&path, "/proc/self/task/%d/comm", t->tid) < 0) {
+		return ENOMEM;
+	}
+
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+
+	int fd;
+	if(int e = sys_open(path, O_WRONLY, 0, &fd); e) {
+		return e;
+	}
+
+	if(int e = sys_write(fd, name, strlen(name) + 1, NULL)) {
+		return e;
+	}
+
+	sys_close(fd);
+
+	pthread_setcancelstate(cs, 0);
+
+	return 0;
+}
+
+int sys_thread_getname(void *tcb, char *name, size_t size) {
+	auto t = reinterpret_cast<Tcb *>(tcb);
+	char *path;
+	int cs = 0;
+	ssize_t real_size = 0;
+
+	if(asprintf(&path, "/proc/self/task/%d/comm", t->tid) < 0) {
+		return ENOMEM;
+	}
+
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+
+	int fd;
+	if(int e = sys_open(path, O_RDONLY | O_CLOEXEC, 0, &fd); e) {
+		return e;
+	}
+
+	if(int e = sys_read(fd, name, size, &real_size)) {
+		return e;
+	}
+
+	name[real_size - 1] = 0;
+	sys_close(fd);
+
+	pthread_setcancelstate(cs, 0);
+
+	if(static_cast<ssize_t>(size) <= real_size) {
+		return ERANGE;
+	}
+
+	return 0;
+}
+
+int sys_mlock(const void *addr, size_t length) {
+	auto ret = do_syscall(SYS_mlock, addr, length);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_munlock(const void *addr, size_t length) {
+	auto ret = do_syscall(SYS_munlock, addr, length);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_munlockall(void) {
+	auto ret = do_syscall(SYS_munlockall);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_mincore(void *addr, size_t length, unsigned char *vec) {
+	auto ret = do_syscall(SYS_mincore, addr, length, vec);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_memfd_create(const char *name, int flags, int *fd) {
+	auto ret = do_syscall(SYS_memfd_create, name, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*fd = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_fallocate(int fd, off_t offset, size_t size) {
+	auto ret = do_syscall(SYS_fallocate, fd, 0, offset, size);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_flock(int fd, int options) {
+	auto ret = do_syscall(SYS_flock, fd, options);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_seteuid(uid_t euid) {
+	return sys_setresuid(-1, euid, -1);
+}
+
+int sys_vm_remap(void *pointer, size_t size, size_t new_size, void **window) {
+	auto ret = do_syscall(SYS_mremap, pointer, size, new_size, MREMAP_MAYMOVE);
+	// TODO: musl fixes up EPERM errors from the kernel.
+	if(int e = sc_error(ret); e)
+		return e;
+	*window = sc_ptr_result<void>(ret);
+	return 0;
+}
+
+int sys_link(const char *old_path, const char *new_path) {
+#ifdef SYS_link
+	auto ret = do_syscall(SYS_link, old_path, new_path);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+#else
+	auto ret = do_syscall(SYS_linkat, AT_FDCWD, old_path, AT_FDCWD, new_path, 0);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+#endif
+}
+
+// Inspired by musl (src/stat/statvfs.c:28 fixup function)
+static void statfs_to_statvfs(struct statfs *from, struct statvfs *to) {
+	*to = {
+		.f_bsize = from->f_bsize,
+		.f_frsize = from->f_frsize ? from->f_frsize : from->f_bsize,
+		.f_blocks = from->f_blocks,
+		.f_bfree = from->f_bfree,
+		.f_bavail = from->f_bavail,
+		.f_files = from->f_files,
+		.f_ffree = from->f_ffree,
+		.f_favail = from->f_ffree,
+		.f_fsid = (unsigned long) from->f_fsid.__val[0],
+		.f_flag = from->f_flags,
+		.f_namemax = from->f_namelen,
+	};
+}
+
+int sys_statvfs(const char *path, struct statvfs *out) {
+	struct statfs buf;
+	if(auto ret = sys_statfs(path, &buf); ret != 0) {
+		return ret;
+	}
+	statfs_to_statvfs(&buf, out);
+	return 0;
+}
+
+int sys_fstatvfs(int fd, struct statvfs *out) {
+	struct statfs buf;
+	if(auto ret = sys_fstatfs(fd, &buf); ret != 0) {
+		return ret;
+	}
+	statfs_to_statvfs(&buf, out);
+	return 0;
+}
+
+int sys_sysconf(int num, long *ret) {
+	switch(num) {
+		case _SC_OPEN_MAX: {
+			struct rlimit ru;
+			if(int e = sys_getrlimit(RLIMIT_NOFILE, &ru); e) {
+				return e;
+			}
+			*ret = (ru.rlim_cur == RLIM_INFINITY) ? -1 : ru.rlim_cur;
+			break;
+		}
+		case _SC_NPROCESSORS_ONLN: {
+			cpu_set_t set;
+			CPU_ZERO(&set);
+			if(int e = sys_getaffinity(0, sizeof(set), &set); e) {
+				return e;
+			}
+			*ret = CPU_COUNT(&set);
+			break;
+		}
+		case _SC_PHYS_PAGES: {
+			struct sysinfo info;
+			if(int e = sys_sysinfo(&info); e) {
+				return e;
+			}
+			unsigned unit = (info.mem_unit) ? info.mem_unit : 1;
+			*ret = std::min(long((info.totalram * unit) / PAGE_SIZE), LONG_MAX);
+			break;
+		}
+		case _SC_CHILD_MAX: {
+			struct rlimit ru;
+			if(int e = sys_getrlimit(RLIMIT_NPROC, &ru); e) {
+				return e;
+			}
+			*ret = (ru.rlim_cur == RLIM_INFINITY) ? -1 : ru.rlim_cur;
+			break;
+		}
+		case _SC_LINE_MAX: {
+			*ret = -1;
+			break;
+		}
+		default: {
+			return EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+int sys_semget(key_t key, int n, int fl, int *id) {
+	auto ret = do_syscall(SYS_semget, key, n, fl);
+	if(int e = sc_error(ret); e)
+		return e;
+	*id = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_semctl(int semid, int semnum, int cmd, void *semun, int *out) {
+	auto ret = do_syscall(SYS_semctl, semid, semnum, cmd | IPC_64, semun);
+	if(int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_waitid(idtype_t idtype, id_t id, siginfo_t *info, int options) {
+	auto ret = do_syscall(SYS_waitid, idtype, id, info, options, 0);
+	if(int e = sc_error(ret); e)
+		return e;
+	return sc_int_result<int>(ret);
+}
+
+#endif // __MLIBC_POSIX_OPTION
+
+#if __MLIBC_LINUX_OPTION
+
+#include <linux/reboot.h>
+
+int sys_reboot(int cmd) {
+	auto ret = do_syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, nullptr);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+#endif // __MLIBC_LINUX_OPTION
+
+int sys_times(struct tms *tms, clock_t *out) {
+	auto ret = do_syscall(SYS_times, tms);
+	if (int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<long>(ret);
+	return 0;
+}
+
+pid_t sys_getpid() {
+	auto ret = do_syscall(SYS_getpid);
+	// getpid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+pid_t sys_gettid() {
+	auto ret = do_syscall(SYS_gettid);
+	// gettid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+uid_t sys_getuid() {
+	auto ret = do_syscall(SYS_getuid);
+	// getuid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+uid_t sys_geteuid() {
+	auto ret = do_syscall(SYS_geteuid);
+	// geteuid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+gid_t sys_getgid() {
+	auto ret = do_syscall(SYS_getgid);
+	// getgid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+gid_t sys_getegid() {
+	auto ret = do_syscall(SYS_getegid);
+	// getegid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+int sys_kill(int pid, int sig) {
+	auto ret = do_syscall(SYS_kill, pid, sig);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_vm_protect(void *pointer, size_t size, int prot) {
+	auto ret = do_syscall(SYS_mprotect, pointer, size, prot);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+void sys_thread_exit() {
+	do_syscall(SYS_exit, 0);
+	__builtin_trap();
+}
+
+void sys_exit(int status) {
+	do_syscall(SYS_exit_group, status);
+	__builtin_trap();
+}
+
+#endif // MLIBC_BUILDING_RTDL
+
+#define FUTEX_WAIT 0
+#define FUTEX_WAKE 1
+
+int sys_futex_tid() {
+	auto ret = do_syscall(SYS_gettid);
+	// gettid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+int sys_futex_wait(int *pointer, int expected, const struct timespec *time) {
+	auto ret = do_cp_syscall(SYS_futex, pointer, FUTEX_WAIT, expected, time);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_futex_wake(int *pointer) {
+	auto ret = do_syscall(SYS_futex, pointer, FUTEX_WAKE, INT_MAX);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_sigsuspend(const sigset_t *set) {
+	auto ret = do_syscall(SYS_rt_sigsuspend, set, NSIG / 8);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_sigaltstack(const stack_t *ss, stack_t *oss) {
+	auto ret = do_syscall(SYS_sigaltstack, ss, oss);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_mkdir(const char *path, mode_t mode) {
+	auto ret = do_syscall(SYS_mkdirat, AT_FDCWD, path, mode);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+
+int sys_mkdirat(int dirfd, const char *path, mode_t mode) {
+	auto ret = do_syscall(SYS_mkdirat, dirfd, path, mode);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_mknodat(int dirfd, const char *path, int mode, int dev) {
+	auto ret = do_syscall(SYS_mknodat, dirfd, path, mode, dev);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_mkfifoat(int dirfd, const char *path, int mode) {
+	return sys_mknodat(dirfd, path, mode | S_IFIFO, 0);
+}
+
+int sys_symlink(const char *target_path, const char *link_path) {
+	auto ret = do_syscall(SYS_symlinkat, target_path, AT_FDCWD, link_path);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_symlinkat(const char *target_path, int dirfd, const char *link_path) {
+	auto ret = do_syscall(SYS_symlinkat, target_path, dirfd, link_path);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_umask(mode_t mode, mode_t *old) {
+	auto ret = do_syscall(SYS_umask, mode);
+	if (int e = sc_error(ret); e)
+		return e;
+	*old = sc_int_result<mode_t>(ret);
+	return 0;
+}
+
+int sys_chdir(const char *path) {
+	auto ret = do_syscall(SYS_chdir, path);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_fchdir(int fd) {
+	auto ret = do_syscall(SYS_fchdir, fd);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_rename(const char *old_path, const char *new_path) {
+	return sys_renameat(AT_FDCWD, old_path, AT_FDCWD, new_path);
+}
+
+int sys_renameat(int old_dirfd, const char *old_path, int new_dirfd, const char *new_path) {
+#ifdef SYS_renameat2
+	auto ret = do_syscall(SYS_renameat2, old_dirfd, old_path, new_dirfd, new_path, 0);
+#else
+	auto ret = do_syscall(SYS_renameat, old_dirfd, old_path, new_dirfd, new_path);
+#endif /* defined(SYS_renameat2) */
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_rmdir(const char *path) {
+	auto ret = do_syscall(SYS_unlinkat, AT_FDCWD, path, AT_REMOVEDIR);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_ftruncate(int fd, size_t size) {
+	auto ret = do_syscall(SYS_ftruncate, fd, size);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_readlink(const char *path, void *buf, size_t bufsiz, ssize_t *len) {
+	auto ret = do_syscall(SYS_readlinkat, AT_FDCWD, path, buf, bufsiz);
+	if (int e = sc_error(ret); e)
+		return e;
+	*len = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_getrlimit(int resource, struct rlimit *limit) {
+	auto ret = do_syscall(SYS_getrlimit, resource, limit);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_setrlimit(int resource, const struct rlimit *limit) {
+	auto ret = do_syscall(SYS_setrlimit, resource, limit);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+pid_t sys_getppid() {
+	auto ret = do_syscall(SYS_getppid);
+	// getppid() always succeeds.
+	return sc_int_result<pid_t>(ret);
+}
+
+int sys_setpgid(pid_t pid, pid_t pgid) {
+	auto ret = do_syscall(SYS_setpgid, pid, pgid);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_getsid(pid_t pid, pid_t *sid) {
+	auto ret = do_syscall(SYS_getsid, pid);
+	if (int e = sc_error(ret); e)
+		return e;
+	*sid = sc_int_result<pid_t>(ret);
+	return 0;
+}
+
+int sys_setsid(pid_t *sid) {
+	auto ret = do_syscall(SYS_setsid);
+	if (int e = sc_error(ret); e)
+		return e;
+	*sid = sc_int_result<pid_t>(ret);
+	return 0;
+}
+
+int sys_setuid(uid_t uid) {
+	auto ret = do_syscall(SYS_setuid, uid);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_setgid(gid_t gid) {
+	auto ret = do_syscall(SYS_setgid, gid);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_getpgid(pid_t pid, pid_t *out) {
+	auto ret = do_syscall(SYS_getpgid, pid);
+	if (int e = sc_error(ret); e)
+		return e;
+	*out = sc_int_result<pid_t>(ret);
+	return 0;
+}
+
+int sys_getgroups(size_t size, const gid_t *list, int *retval) {
+	auto ret = do_syscall(SYS_getgroups, size, list);
+	if (int e = sc_error(ret); e)
+		return e;
+	*retval = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_dup(int fd, int flags, int *newfd) {
+	__ensure(!flags);
+	auto ret = do_cp_syscall(SYS_dup, fd);
+	if (int e = sc_error(ret); e)
+		return e;
+	*newfd = sc_int_result<int>(ret);
+	return 0;
+}
+
+void sys_sync() {
+	do_syscall(SYS_sync);
+}
+
+int sys_fsync(int fd) {
+	auto ret = do_syscall(SYS_fsync, fd);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_fdatasync(int fd) {
+	auto ret = do_syscall(SYS_fdatasync, fd);
+	if (int e = sc_error(ret); e)
+		return e;
+	return 0;
+}
+
+int sys_getrandom(void *buffer, size_t length, int flags, ssize_t *bytes_written) {
+	auto ret = do_syscall(SYS_getrandom, buffer, length, flags);
+	if (int e = sc_error(ret); e)
+		return e;
+	*bytes_written = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_getentropy(void *buffer, size_t length) {
+	ssize_t written;
+	return sys_getrandom(buffer, length, 0, &written);
+}
+
+int sys_setxattr(const char *path, const char *name, const void *val,
+		size_t size, int flags) {
+	auto ret = do_syscall(SYS_setxattr, path, name, val, size, flags);
+	return sc_error(ret);
+}
+
+int sys_lsetxattr(const char *path, const char *name, const void *val,
+		size_t size, int flags) {
+	auto ret = do_syscall(SYS_lsetxattr, path, name, val, size, flags);
+	return sc_error(ret);
+}
+
+int sys_fsetxattr(int fd, const char *name, const void *val,
+		size_t size, int flags) {
+	auto ret = do_syscall(SYS_fsetxattr, fd, name, val, size, flags);
+	return sc_error(ret);
+}
+
+int sys_getxattr(const char *path, const char *name, void *val, size_t size,
+		ssize_t *nread) {
+	auto ret = do_syscall(SYS_getxattr, path, name, val, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*nread = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_lgetxattr(const char *path, const char *name, void *val, size_t size,
+		ssize_t *nread) {
+	auto ret = do_syscall(SYS_lgetxattr, path, name, val, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*nread = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_fgetxattr(int fd, const char *name, void *val, size_t size,
+		ssize_t *nread) {
+	auto ret = do_syscall(SYS_fgetxattr, fd, name, val, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*nread = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_removexattr(const char *path, const char *name) {
+	auto ret = do_syscall(SYS_removexattr, path, name);
+	return sc_error(ret);
+}
+
+int sys_lremovexattr(const char *path, const char *name) {
+	auto ret = do_syscall(SYS_lremovexattr, path, name);
+	return sc_error(ret);
+}
+
+int sys_fremovexattr(int fd, const char *name) {
+	auto ret = do_syscall(SYS_fremovexattr, fd, name);
+	return sc_error(ret);
+}
+
+int sys_listxattr(const char *path, char *list, size_t size, ssize_t *nread) {
+	auto ret = do_syscall(SYS_listxattr, path, list, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*nread = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_llistxattr(const char *path, char *list, size_t size, ssize_t *nread) {
+	auto ret = do_syscall(SYS_llistxattr, path, list, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*nread = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_flistxattr(int fd, char *list, size_t size, ssize_t *nread) {
+	auto ret = do_syscall(SYS_flistxattr, fd, list, size);
+	if (int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*nread = sc_int_result<ssize_t>(ret);
+	return 0;
+}
+
+int sys_sigtimedwait(const sigset_t *__restrict set, siginfo_t *__restrict info, const struct timespec *__restrict timeout, int *out_signal) {
+	auto ret = do_syscall(SYS_rt_sigtimedwait, set, info, timeout, NSIG / 8);
+
+	if (int e = sc_error(ret); e)
+		return e;
+
+	*out_signal = sc_int_result<int>(ret);
+
+	return 0;
+}
+
+#if __MLIBC_BSD_OPTION
+int sys_brk(void **out) {
+	auto ret = do_syscall(SYS_brk, 0);
+	if(int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*out = (void *) sc_int_result<uintptr_t>(ret);
+	return 0;
+}
+#endif // __MLIBC_BSD_OPTION
+
+#if __MLIBC_GLIBC_OPTION
+
+int sys_personality(unsigned long persona, int *out) {
+	auto ret = do_syscall(SYS_personality, persona);
+
+	if(int e = sc_error(ret); e) {
+		return e;
+	}
+
+	*out = sc_int_result<int>(ret);
+	return 0;
+}
+
+int sys_ioperm(unsigned long int from, unsigned long int num, int turn_on) {
+#if defined(SYS_ioperm)
+	auto ret = do_syscall(SYS_ioperm, from, num, turn_on);
+
+	if(int e = sc_error(ret); e) {
+		return e;
+	}
+
+	return 0;
+#else
+	(void) from;
+	(void) num;
+	(void) turn_on;
+	return ENOSYS;
+#endif
+}
+
+int sys_iopl(int level) {
+#if defined(SYS_iopl)
+	auto ret = do_syscall(SYS_iopl, level);
+
+	if(int e = sc_error(ret); e) {
+		return e;
+	}
+
+	return 0;
+#else
+	(void) level;
+	return ENOSYS;
+#endif
+}
+
+#endif // __MLIBC_GLIBC_OPTION
+
+} // namespace mlibc
diff --git a/lib/mlibc/sysdeps/linux/generic/thread.cpp b/lib/mlibc/sysdeps/linux/generic/thread.cpp
new file mode 100644
index 0000000..e413e4f
--- /dev/null
+++ b/lib/mlibc/sysdeps/linux/generic/thread.cpp
@@ -0,0 +1,60 @@
+#include <mlibc/thread-entry.hpp>
+#include <mlibc/all-sysdeps.hpp>
+#include <mlibc/thread.hpp>
+#include <bits/ensure.h>
+#include <sys/mman.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <errno.h>
+
+extern "C" void __mlibc_enter_thread(void *entry, void *user_arg) {
+	// The linux kernel already sets the TCB in sys_clone().
+	auto tcb = mlibc::get_current_tcb();
+
+	// Wait until our parent sets up the TID.
+	while(!__atomic_load_n(&tcb->tid, __ATOMIC_RELAXED))
+		mlibc::sys_futex_wait(&tcb->tid, 0, nullptr);
+
+	tcb->invokeThreadFunc(entry, user_arg);
+
+	__atomic_store_n(&tcb->didExit, 1, __ATOMIC_RELEASE);
+	mlibc::sys_futex_wake(&tcb->didExit);
+
+	mlibc::sys_thread_exit();
+}
+
+namespace mlibc {
+
+static constexpr size_t default_stacksize = 0x200000;
+
+int sys_prepare_stack(void **stack, void *entry, void *user_arg, void *tcb, size_t *stack_size, size_t *guard_size, void **stack_base) {
+	(void)tcb;
+	if (!*stack_size)
+		*stack_size = default_stacksize;
+
+	uintptr_t map;
+	if (*stack) {
+		map = reinterpret_cast<uintptr_t>(*stack);
+		*guard_size = 0;
+	} else {
+		map = reinterpret_cast<uintptr_t>(
+				mmap(nullptr, *stack_size + *guard_size,
+					PROT_NONE,
+					MAP_PRIVATE | MAP_ANONYMOUS, -1, 0)
+				);
+		if (reinterpret_cast<void*>(map) == MAP_FAILED)
+			return EAGAIN;
+		int ret = mprotect(reinterpret_cast<void*>(map + *guard_size), *stack_size,
+				PROT_READ | PROT_WRITE);
+		if(ret)
+			return EAGAIN;
+	}
+
+	*stack_base = reinterpret_cast<void*>(map);
+	auto sp = reinterpret_cast<uintptr_t*>(map + *guard_size + *stack_size);
+	*--sp = reinterpret_cast<uintptr_t>(user_arg);
+	*--sp = reinterpret_cast<uintptr_t>(entry);
+	*stack = reinterpret_cast<void*>(sp);
+	return 0;
+}
+} // namespace mlibc