Kernel/LibC: Implement super basic select

This does not really even block but it works... :D

kernel/include/kernel/Device/DebugDevice.h

@@ -21,6 +21,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override { return 0; }
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan buffer) override;
 
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		const dev_t m_rdev;
 	};

kernel/include/kernel/Device/FramebufferDevice.h

@@ -30,6 +30,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan) override;
 
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		FramebufferDevice(mode_t mode, uid_t uid, gid_t gid, dev_t rdev, paddr_t paddr, uint32_t width, uint32_t height, uint32_t pitch, uint8_t bpp);
 		BAN::ErrorOr<void> initialize();

kernel/include/kernel/Device/NullDevice.h

@@ -23,6 +23,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override { return 0; }
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan buffer) override { return buffer.size(); };
 
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		const dev_t m_rdev;
 	};

kernel/include/kernel/Device/ZeroDevice.h

@@ -21,6 +21,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan buffer) override { return buffer.size(); };
 
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		const dev_t m_rdev;
 	};

kernel/include/kernel/FS/Ext2/Inode.h

@@ -43,6 +43,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<void> truncate_impl(size_t) override;
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t) override;
 
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		// Returns maximum number of data blocks in use
 		// NOTE: the inode might have more blocks than what this suggests if it has been shrinked

kernel/include/kernel/FS/Inode.h

@@ -113,7 +113,11 @@ namespace Kernel
 		BAN::ErrorOr<void> truncate(size_t);
 		BAN::ErrorOr<void> chmod(mode_t);
 		BAN::ErrorOr<void> chown(uid_t, gid_t);
-		bool has_data() const;
+
+		// Select/Non blocking API
+		bool can_read() const;
+		bool can_write() const;
+		bool has_error() const;
 
 		BAN::ErrorOr<long> ioctl(int request, void* arg);
 
@@ -144,7 +148,11 @@ namespace Kernel
 		virtual BAN::ErrorOr<void> truncate_impl(size_t)					{ return BAN::Error::from_errno(ENOTSUP); }
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t)						{ return BAN::Error::from_errno(ENOTSUP); }
 		virtual BAN::ErrorOr<void> chown_impl(uid_t, gid_t)					{ return BAN::Error::from_errno(ENOTSUP); }
-		virtual bool has_data_impl() const { dwarnln("nonblock not supported"); return true; }
+
+		// Select/Non blocking API
+		virtual bool can_read_impl() const = 0;
+		virtual bool can_write_impl() const = 0;
+		virtual bool has_error_impl() const = 0;
 
 		virtual BAN::ErrorOr<long> ioctl_impl(int request, void* arg)		{ return BAN::Error::from_errno(ENOTSUP); }
 

kernel/include/kernel/FS/Pipe.h

@@ -34,6 +34,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan) override;
 
+		virtual bool can_read_impl() const override { return !m_buffer.empty(); }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		Pipe(const Credentials&);
 

kernel/include/kernel/FS/ProcFS/Inode.h

@@ -43,7 +43,10 @@ namespace Kernel
 		// You may not write here and this is always non blocking
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan) override		{ return BAN::Error::from_errno(EINVAL); }
 		virtual BAN::ErrorOr<void> truncate_impl(size_t) override						{ return BAN::Error::from_errno(EINVAL); }
-		virtual bool has_data_impl() const override										{ return true; }
+
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
 
 	private:
 		ProcROInode(Process&, size_t (Process::*)(off_t, BAN::ByteSpan) const, TmpFileSystem&, const TmpInodeInfo&);

kernel/include/kernel/FS/TmpFS/Inode.h

@@ -72,7 +72,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan) override;
 		virtual BAN::ErrorOr<void> truncate_impl(size_t) override;
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t) override;
-		virtual bool has_data_impl() const override { return true; }
+
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
 
 	private:
 		TmpFileInode(TmpFileSystem&, ino_t, const TmpInodeInfo&);
@@ -91,7 +94,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan) override { return BAN::Error::from_errno(ENODEV); }
 		virtual BAN::ErrorOr<void> truncate_impl(size_t) override { return BAN::Error::from_errno(ENODEV); }
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t) override;
-		virtual bool has_data_impl() const override { return true; }
+
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
 
 	private:
 		TmpSocketInode(TmpFileSystem&, ino_t, const TmpInodeInfo&);
@@ -110,6 +116,10 @@ namespace Kernel
 	protected:
 		virtual BAN::ErrorOr<BAN::String> link_target_impl() override;
 
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		TmpSymlinkInode(TmpFileSystem&, ino_t, const TmpInodeInfo&);
 	};
@@ -136,6 +146,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<void> create_directory_impl(BAN::StringView, mode_t, uid_t, gid_t) override final;
 		virtual BAN::ErrorOr<void> unlink_impl(BAN::StringView) override;
 
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		template<TmpFuncs::for_each_valid_entry_callback F>
 		void for_each_valid_entry(F callback);

kernel/include/kernel/Input/PS2/Keyboard.h

@@ -48,7 +48,10 @@ namespace Kernel::Input
 
 	protected:
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
-		virtual bool has_data_impl() const override;
+
+		virtual bool can_read_impl() const override { return !m_event_queue.empty(); }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
 	};
 
 }

kernel/include/kernel/Input/PS2/Mouse.h

@@ -42,7 +42,10 @@ namespace Kernel::Input
 
 	protected:
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
-		virtual bool has_data_impl() const override;
+
+		virtual bool can_read_impl() const override { return !m_event_queue.empty(); }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
 	};
 
 }

kernel/include/kernel/Networking/E1000/E1000.h

@@ -46,6 +46,10 @@ namespace Kernel
 
 		virtual BAN::ErrorOr<void> send_bytes(BAN::MACAddress destination, EtherType protocol, BAN::ConstByteSpan) override;
 
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		BAN::ErrorOr<void> read_mac_address();
 

kernel/include/kernel/Networking/TCPSocket.h

@@ -57,6 +57,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> sendto_impl(BAN::ConstByteSpan message, const sockaddr* address, socklen_t address_len) override;
 		virtual BAN::ErrorOr<size_t> recvfrom_impl(BAN::ByteSpan message, sockaddr* address, socklen_t* address_len) override;
 
+		virtual bool can_read_impl() const override { return m_recv_window.data_size; }
+		virtual bool can_write_impl() const override { return m_state == State::Established; }
+		virtual bool has_error_impl() const override { return m_state != State::Established && m_state != State::Listen && m_state != State::SynSent && m_state != State::SynReceived; }
+
 	private:
 		enum class State
 		{

kernel/include/kernel/Networking/UDPSocket.h

@@ -38,6 +38,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> sendto_impl(BAN::ConstByteSpan message, const sockaddr* address, socklen_t address_len) override;
 		virtual BAN::ErrorOr<size_t> recvfrom_impl(BAN::ByteSpan buffer, sockaddr* address, socklen_t* address_len) override;
 
+		virtual bool can_read_impl() const override { return !m_packets.empty(); }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		UDPSocket(NetworkLayer&, ino_t, const TmpInodeInfo&);
 

kernel/include/kernel/Networking/UNIX/Socket.h

@@ -26,6 +26,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<size_t> sendto_impl(BAN::ConstByteSpan, const sockaddr*, socklen_t) override;
 		virtual BAN::ErrorOr<size_t> recvfrom_impl(BAN::ByteSpan, sockaddr*, socklen_t*) override;
 
+		virtual bool can_read_impl() const override;
+		virtual bool can_write_impl() const override;
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		UnixDomainSocket(SocketType, ino_t, const TmpInodeInfo&);
 

kernel/include/kernel/Process.h

@@ -16,6 +16,7 @@
 
 #include <sys/banan-os.h>
 #include <sys/mman.h>
+#include <sys/select.h>
 #include <sys/socket.h>
 #include <termios.h>
 
@@ -126,6 +127,8 @@ namespace Kernel
 
 		BAN::ErrorOr<long> sys_ioctl(int fildes, int request, void* arg);
 
+		BAN::ErrorOr<long> sys_pselect(sys_pselect_t* arguments);
+
 		BAN::ErrorOr<long> sys_pipe(int fildes[2]);
 		BAN::ErrorOr<long> sys_dup(int fildes);
 		BAN::ErrorOr<long> sys_dup2(int fildes, int fildes2);

kernel/include/kernel/Storage/NVMe/Controller.h

@@ -24,6 +24,11 @@ namespace Kernel
 		virtual dev_t rdev() const override { return m_rdev; }
 		virtual BAN::StringView name() const override { return m_name; }
 
+	protected:
+		virtual bool can_read_impl() const override { return false; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		NVMeController(PCI::Device& pci_device);
 		virtual BAN::ErrorOr<void> initialize() override;

kernel/include/kernel/Storage/Partition.h

@@ -46,6 +46,10 @@ namespace Kernel
 	protected:
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
 
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		const dev_t m_rdev;
 	};

kernel/include/kernel/Storage/StorageDevice.h

@@ -39,6 +39,10 @@ namespace Kernel
 		virtual BAN::ErrorOr<void> write_sectors_impl(uint64_t lba, uint64_t sector_count, BAN::ConstByteSpan) = 0;
 		void add_disk_cache();
 
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
+
 	private:
 		SpinLock							m_lock;
 		BAN::Optional<DiskCache>			m_disk_cache;

kernel/include/kernel/Terminal/TTY.h

@@ -44,7 +44,9 @@ namespace Kernel
 		virtual BAN::ErrorOr<void> chmod_impl(mode_t) override;
 		virtual BAN::ErrorOr<void> chown_impl(uid_t, gid_t) override;
 
-		virtual bool has_data_impl() const override;
+		virtual bool can_read_impl() const override { return m_output.flush; }
+		virtual bool can_write_impl() const override { return true; }
+		virtual bool has_error_impl() const override { return false; }
 
 	protected:
 		TTY(mode_t mode, uid_t uid, gid_t gid)

kernel/kernel/FS/Inode.cpp

@@ -201,10 +201,22 @@ namespace Kernel
 		return chown_impl(uid, gid);
 	}
 
-	bool Inode::has_data() const
+	bool Inode::can_read() const
 	{
 		LockGuard _(m_lock);
-		return has_data_impl();
+		return can_read_impl();
+	}
+
+	bool Inode::can_write() const
+	{
+		LockGuard _(m_lock);
+		return can_write_impl();
+	}
+
+	bool Inode::has_error() const
+	{
+		LockGuard _(m_lock);
+		return has_error_impl();
 	}
 
 	BAN::ErrorOr<long> Inode::ioctl(int request, void* arg)

kernel/kernel/Input/PS2/Keyboard.cpp

@@ -208,10 +208,4 @@ namespace Kernel::Input
 		}
 	}
 
-	bool PS2Keyboard::has_data_impl() const
-	{
-		CriticalScope _;
-		return !m_event_queue.empty();
-	}
-
 }

kernel/kernel/Input/PS2/Mouse.cpp

@@ -192,10 +192,4 @@ namespace Kernel::Input
 		}
 	}
 
-	bool PS2Mouse::has_data_impl() const
-	{
-		CriticalScope _;
-		return !m_event_queue.empty();
-	}
-
 }

kernel/kernel/Networking/UNIX/Socket.cpp

@@ -248,6 +248,29 @@ namespace Kernel
 		return {};
 	}
 
+	bool UnixDomainSocket::can_read_impl() const
+	{
+		if (m_info.has<ConnectionInfo>())
+		{
+			auto& connection_info = m_info.get<ConnectionInfo>();
+			if (!connection_info.connection)
+				return false;
+		}
+
+		return m_packet_size_total > 0;
+	}
+
+	bool UnixDomainSocket::can_write_impl() const
+	{
+		if (m_info.has<ConnectionInfo>())
+		{
+			auto& connection_info = m_info.get<ConnectionInfo>();
+			return connection_info.connection.valid();
+		}
+
+		return true;
+	}
+
 	BAN::ErrorOr<size_t> UnixDomainSocket::sendto_impl(BAN::ConstByteSpan message, const sockaddr* address, socklen_t address_len)
 	{
 		if (message.size() > s_packet_buffer_size)

kernel/kernel/OpenFileDescriptorSet.cpp

@@ -331,7 +331,7 @@ namespace Kernel
 	{
 		TRY(validate_fd(fd));
 		auto& open_file = m_open_files[fd];
-		if ((open_file->flags & O_NONBLOCK) && !open_file->inode->has_data())
+		if ((open_file->flags & O_NONBLOCK) && !open_file->inode->can_read())
 			return 0;
 		size_t nread = TRY(open_file->inode->read(open_file->offset, buffer));
 		open_file->offset += nread;
@@ -342,6 +342,8 @@ namespace Kernel
 	{
 		TRY(validate_fd(fd));
 		auto& open_file = m_open_files[fd];
+		if ((open_file->flags & O_NONBLOCK) && !open_file->inode->can_write())
+			return 0;
 		if (open_file->flags & O_APPEND)
 			open_file->offset = open_file->inode->size();
 		size_t nwrite = TRY(open_file->inode->write(open_file->offset, buffer));

kernel/kernel/Process.cpp

@@ -1018,6 +1018,86 @@ namespace Kernel
 		return TRY(inode->ioctl(request, arg));
 	}
 
+	BAN::ErrorOr<long> Process::sys_pselect(sys_pselect_t* arguments)
+	{
+		LockGuard _(m_lock);
+
+		TRY(validate_pointer_access(arguments, sizeof(sys_pselect_t)));
+		if (arguments->readfds)
+			TRY(validate_pointer_access(arguments->readfds, sizeof(fd_set)));
+		if (arguments->writefds)
+			TRY(validate_pointer_access(arguments->writefds, sizeof(fd_set)));
+		if (arguments->errorfds)
+			TRY(validate_pointer_access(arguments->errorfds, sizeof(fd_set)));
+		if (arguments->timeout)
+			TRY(validate_pointer_access(arguments->timeout, sizeof(timespec)));
+		if (arguments->sigmask)
+			TRY(validate_pointer_access(arguments->sigmask, sizeof(sigset_t)));
+
+		if (arguments->sigmask)
+			return BAN::Error::from_errno(ENOTSUP);
+
+		uint64_t timedout_ms = SystemTimer::get().ms_since_boot();
+		if (arguments->timeout)
+		{
+			timedout_ms += arguments->timeout->tv_sec * 1000;
+			timedout_ms += arguments->timeout->tv_nsec / 1'000'000;
+		}
+
+		fd_set readfds;		FD_ZERO(&readfds);
+		fd_set writefds;	FD_ZERO(&writefds);
+		fd_set errorfds;	FD_ZERO(&errorfds);
+
+		long set_bits = 0;
+		while (set_bits == 0)
+		{
+			if (arguments->timeout && SystemTimer::get().ms_since_boot() >= timedout_ms)
+				break;
+
+			auto update_fds =
+				[&](int fd, fd_set* source, fd_set* dest, bool (Inode::*func)() const)
+				{
+					if (source == nullptr)
+						return;
+
+					if (!FD_ISSET(fd, source))
+						return;
+
+					auto inode_or_error = m_open_file_descriptors.inode_of(fd);
+					if (inode_or_error.is_error())
+						return;
+
+					auto inode = inode_or_error.release_value();
+					auto mode = inode->mode();
+					if (!mode.ifreg() && !mode.ififo() && !mode.ifsock() && !inode->is_pipe() && !inode->is_tty())
+						return;
+
+					if ((inode_or_error.value().ptr()->*func)())
+					{
+						FD_SET(fd, dest);
+						set_bits++;
+					}
+				};
+
+			for (int i = 0; i < arguments->nfds; i++)
+			{
+				update_fds(i, arguments->readfds, &readfds, &Inode::can_read);
+				update_fds(i, arguments->writefds, &writefds, &Inode::can_write);
+				update_fds(i, arguments->errorfds, &errorfds, &Inode::can_read);
+			}
+
+			SystemTimer::get().sleep(1);
+		}
+
+		if (arguments->readfds)
+			memcpy(arguments->readfds, &readfds, sizeof(fd_set));
+		if (arguments->writefds)
+			memcpy(arguments->writefds, &writefds, sizeof(fd_set));
+		if (arguments->errorfds)
+			memcpy(arguments->errorfds, &errorfds, sizeof(fd_set));
+		return set_bits;
+	}
+
 	BAN::ErrorOr<long> Process::sys_pipe(int fildes[2])
 	{
 		LockGuard _(m_lock);

kernel/kernel/Syscall.cpp

@@ -237,6 +237,9 @@ namespace Kernel
 		case SYS_LISTEN:
 			ret = Process::current().sys_listen((int)arg1, (int)arg2);
 			break;
+		case SYS_PSELECT:
+			ret = Process::current().sys_pselect((sys_pselect_t*)arg1);
+			break;
 		default:
 			dwarnln("Unknown syscall {}", syscall);
 			break;

kernel/kernel/Terminal/TTY.cpp

@@ -358,12 +358,6 @@ namespace Kernel
 		return buffer.size();
 	}
 
-	bool TTY::has_data_impl() const
-	{
-		LockGuard _(m_lock);
-		return m_output.flush;
-	}
-
 	void TTY::putchar_current(uint8_t ch)
 	{
 		ASSERT(s_tty);

libc/CMakeLists.txt

@@ -21,6 +21,7 @@ set(LIBC_SOURCES
 	stropts.cpp
 	sys/banan-os.cpp
 	sys/mman.cpp
+	sys/select.cpp
 	sys/socket.cpp
 	sys/stat.cpp
 	sys/wait.cpp

libc/include/bits/types/timeval.h

@@ -0,0 +1,20 @@
+#ifndef _BITS_TIMEVAL_H
+#define _BITS_TIMEVAL_H 1
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+#define __need_time_t
+#define __need_suseconds_t
+#include <sys/types.h>
+
+struct timeval
+{
+	time_t		tv_sec;		/* Seconds. */
+	suseconds_t	tc_usec;	/* Microseconds. */
+};
+
+__END_DECLS
+
+#endif

libc/include/sys/select.h

@@ -7,9 +7,7 @@
 
 __BEGIN_DECLS
 
-#define __need_time_t
-#define __need_suseconds_t
-#include <sys/types.h>
+#include <bits/types/timeval.h>
 
 #include <signal.h>
 #include <time.h>
@@ -50,6 +48,16 @@ typedef struct {
 			(setp)->__bits[i] = (__fd_mask)0; \
 	} while (0)
 
+struct sys_pselect_t
+{
+	int nfds;
+	fd_set* readfds;
+	fd_set* writefds;
+	fd_set* errorfds;
+	const struct timespec* timeout;
+	const sigset_t* sigmask;
+};
+
 int pselect(int nfds, fd_set* __restrict readfds, fd_set* __restrict writefds, fd_set* __restrict errorfds, const struct timespec* __restrict timeout, const sigset_t* __restrict sigmask);
 int select(int nfds, fd_set* __restrict readfds, fd_set* __restrict writefds, fd_set* __restrict errorfds, struct timeval* __restrict timeout);
 

libc/include/sys/syscall.h

@@ -71,6 +71,7 @@ __BEGIN_DECLS
 #define SYS_ACCEPT 70
 #define SYS_CONNECT 71
 #define SYS_LISTEN 72
+#define SYS_PSELECT 73
 
 __END_DECLS
 

libc/include/sys/time.h

@@ -7,18 +7,10 @@
 
 __BEGIN_DECLS
 
-#define __need_time_t
-#define __need_suseconds_t
-#include <sys/types.h>
-
 // NOTE: select is declared from here
 #include <sys/select.h>
 
-struct timeval
-{
-	time_t		tv_sec;		/* Seconds. */
-	suseconds_t	tc_usec;	/* Microseconds. */
-};
+#include <bits/types/timeval.h>
 
 struct itimerval
 {

libc/sys/select.cpp

@@ -0,0 +1,31 @@
+#include <sys/select.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+int pselect(int nfds, fd_set* __restrict readfds, fd_set* __restrict writefds, fd_set* __restrict errorfds, const struct timespec* __restrict timeout, const sigset_t* __restrict sigmask)
+{
+	sys_pselect_t arguments {
+		.nfds = nfds,
+		.readfds = readfds,
+		.writefds = writefds,
+		.errorfds = errorfds,
+		.timeout = timeout,
+		.sigmask = sigmask
+	};
+	return syscall(SYS_PSELECT, &arguments);
+}
+
+int select(int nfds, fd_set* __restrict readfds, fd_set* __restrict writefds, fd_set* __restrict errorfds, struct timeval* __restrict timeout)
+{
+	timespec* pts = nullptr;
+	timespec ts;
+	if (timeout)
+	{
+		ts.tv_sec = timeout->tv_sec;
+		ts.tv_nsec = timeout->tc_usec * 1000;
+		pts = &ts;
+	}
+
+	// TODO: "select may update timeout", should we?
+	return pselect(nfds, readfds, writefds, errorfds, pts, nullptr);
+}