Shell: Get default backspace key from c_cc[VERASE]

kernel/include/kernel/Terminal/TTY.h

@@ -12,6 +12,20 @@
 namespace Kernel
 {
 
+#define TTY_DEFAULT_TERMIOS_CC { \
+		[VEOF]   = '\x04', /* ctrl+D */ \
+		[VEOL]   = '\0',                \
+		[VERASE] = '\b',                \
+		[VINTR]  = '\x03', /* ctrl+C */ \
+		[VKILL]  = '\x15', /* ctrl+U */ \
+		[VMIN]   = 0,                   \
+		[VQUIT]  = '\x1c', /* ctrl+\ */ \
+		[VSTART] = '\x11', /* ctrl+Q */ \
+		[VSTOP]  = '\x13', /* ctrl+S */ \
+		[VSUSP]  = '\x1a', /* ctrl+Z */ \
+		[VTIME]  = 0                    \
+	}
+
 	class TTY : public CharacterDevice
 	{
 	public:

kernel/kernel/Terminal/PseudoTerminal.cpp

@@ -162,8 +162,8 @@ namespace Kernel
 			.c_iflag = 0,
 			.c_oflag = 0,
 			.c_cflag = CS8,
-			.c_lflag = ECHO | ICANON,
-			.c_cc = {},
+			.c_lflag = ECHO | ICANON | ISIG,
+			.c_cc = TTY_DEFAULT_TERMIOS_CC,
 			.c_ospeed = B38400,
 			.c_ispeed = B38400,
 		  }, mode, uid, gid)

kernel/kernel/Terminal/Serial.cpp

@@ -174,8 +174,8 @@ namespace Kernel
 			.c_iflag = ICRNL,
 			.c_oflag = OPOST | ONLCR,
 			.c_cflag = CS8,
-			.c_lflag = ECHO | ICANON,
-			.c_cc = {},
+			.c_lflag = ECHO | ICANON | ISIG,
+			.c_cc = TTY_DEFAULT_TERMIOS_CC,
 			.c_ospeed = B38400,
 			.c_ispeed = B38400,
 		  }, 0600, 0, 0)

kernel/kernel/Terminal/TTY.cpp

@@ -18,6 +18,9 @@
 #include <sys/epoll.h>
 #include <sys/sysmacros.h>
 
+#define NL '\n'
+#define CR '\r'
+
 namespace Kernel
 {
 
@@ -216,53 +219,85 @@ namespace Kernel
 
 	void TTY::handle_input_byte(uint8_t ch)
 	{
-		if (ch == 0)
+		if (ch == _POSIX_VDISABLE)
 			return;
 
 		LockGuard _(m_mutex);
 
-		if ((m_termios.c_iflag & ISTRIP))
-			ch &= 0x7F;
-		if ((m_termios.c_iflag & IGNCR) && ch == '\r')
-			return;
-		uint8_t conv = ch;
-		if ((m_termios.c_iflag & ICRNL) && ch == '\r')
-			conv = '\n';
-		if ((m_termios.c_iflag & INLCR) && ch == '\n')
-			conv = '\r';
-		ch = conv;
-
-		// ^C
-		if (ch == '\x03')
+		if (m_termios.c_lflag & ICANON)
 		{
-			if (auto ret = Process::kill(-m_foreground_pgrp, SIGINT); ret.is_error())
-				dwarnln("TTY: {}", ret.error());
-			return;
+			if ((m_termios.c_iflag & ISTRIP))
+				ch &= 0x7F;
+			if ((m_termios.c_iflag & IGNCR) && ch == CR)
+				return;
+			uint8_t conv = ch;
+			if ((m_termios.c_iflag & ICRNL) && ch == CR)
+				conv = NL;
+			if ((m_termios.c_iflag & INLCR) && ch == NL)
+				conv = CR;
+			ch = conv;
 		}
 
-		// ^D + canonical
-		if (ch == '\x04' && (m_termios.c_lflag & ICANON))
+		if (m_termios.c_lflag & ISIG)
 		{
-			m_output.flush = true;
-			epoll_notify(EPOLLIN);
-			m_output.thread_blocker.unblock();
-			return;
+			int sig = -1;
+			if (ch == m_termios.c_cc[VINTR])
+				sig = SIGINT;
+			if (ch == m_termios.c_cc[VQUIT])
+				sig = SIGQUIT;
+			if (ch == m_termios.c_cc[VSUSP])
+				sig = SIGTSTP;
+			if (sig != -1)
+			{
+				if (auto ret = Process::kill(-m_foreground_pgrp, sig); ret.is_error())
+					dwarnln("TTY: {}", ret.error());
+				return;
+			}
 		}
 
-		// backspace + canonical
-		if (ch == '\b' && (m_termios.c_lflag & ICANON))
+		bool should_append = true;
+		bool should_flush = false;
+		bool force_echo = false;
+
+		if (!(m_termios.c_lflag & ICANON))
+			should_flush = true;
+		else
 		{
-			do_backspace();
-			return;
+			if (ch == m_termios.c_cc[VERASE] && (m_termios.c_lflag & ECHOE))
+				return do_backspace();
+
+			//if (ch == m_termios.c_cc[VKILL] && (m_termios.c_lflag & ECHOK))
+			//	;
+
+			if (ch == m_termios.c_cc[VEOF])
+			{
+				should_append = false;
+				should_flush = true;
+			}
+
+			if (ch == NL || ch == m_termios.c_cc[VEOL])
+			{
+				should_append = true;
+				should_flush = true;
+				force_echo = !!(m_termios.c_lflag & ECHONL);
+				ch = NL;
+			}
 		}
 
-		// FIXME: don't ignore these bytes
-		if (m_output.bytes >= m_output.buffer.size())
-			return;
+		// TODO: terminal suspension with VSTOP/VSTART
 
-		m_output.buffer[m_output.bytes++] = ch;
+		if (should_append)
+		{
+			// FIXME: don't ignore these bytes
+			if (m_output.bytes >= m_output.buffer.size())
+			{
+				dwarnln("TTY input full");
+				return;
+			}
+			m_output.buffer[m_output.bytes++] = ch;
+		}
 
-		if (m_termios.c_lflag & ECHO)
+		if (force_echo || (m_termios.c_lflag & ECHO))
 		{
 			if ((ch <= 31 || ch == 127) && ch != '\n')
 			{
@@ -288,7 +323,7 @@ namespace Kernel
 			}
 		}
 
-		if (ch == '\n' || !(m_termios.c_lflag & ICANON) || m_output.bytes == m_output.buffer.size())
+		if (should_flush)
 		{
 			m_output.flush = true;
 			epoll_notify(EPOLLIN);
@@ -346,10 +381,10 @@ namespace Kernel
 			return true;
 		if (m_termios.c_oflag & OPOST)
 		{
-			if ((m_termios.c_oflag & ONLCR) && ch == '\n')
-				return putchar_impl('\r') && putchar_impl('\n');
-			if ((m_termios.c_oflag & OCRNL) && ch == '\r')
-				return putchar_impl('\n');
+			if ((m_termios.c_oflag & ONLCR) && ch == NL)
+				return putchar_impl(CR) && putchar_impl(NL);
+			if ((m_termios.c_oflag & OCRNL) && ch == CR)
+				return putchar_impl(NL);
 		}
 		return putchar_impl(ch);
 	}
@@ -372,7 +407,7 @@ namespace Kernel
 		size_t to_copy = max_to_copy;
 		if (m_termios.c_lflag & ICANON)
 			for (to_copy = 1; to_copy < max_to_copy; to_copy++)
-				if (m_output.buffer[to_copy - 1] == '\n')
+				if (m_output.buffer[to_copy - 1] == NL)
 					break;
 
 		memcpy(buffer.data(), m_output.buffer.data(), to_copy);

kernel/kernel/Terminal/VirtualTTY.cpp

@@ -40,8 +40,8 @@ namespace Kernel
 			.c_iflag = 0,
 			.c_oflag = 0,
 			.c_cflag = CS8,
-			.c_lflag = ECHO | ICANON,
-			.c_cc = {},
+			.c_lflag = ECHO | ICANON | ISIG,
+			.c_cc = TTY_DEFAULT_TERMIOS_CC,
 			.c_ospeed = B38400,
 			.c_ispeed = B38400,
 		  }, 0600, 0, 0)

userspace/programs/CMakeLists.txt

@@ -23,6 +23,7 @@ set(USERSPACE_PROGRAMS
 	ls
 	meminfo
 	mkdir
+	nologin
 	nslookup
 	poweroff
 	ProgramLauncher

userspace/programs/Shell/Input.cpp

@@ -382,7 +382,17 @@ BAN::Optional<BAN::String> Input::get_input(BAN::Optional<BAN::StringView> custo
 			continue;
 		}
 
-		switch (ch)
+		if (ch == m_backspace)
+		{
+			if (m_buffer_col <= 0)
+				continue;
+			while ((m_buffers[m_buffer_index][m_buffer_col - 1] & 0xC0) == 0x80)
+				m_buffers[m_buffer_index].remove(--m_buffer_col);
+			m_buffers[m_buffer_index].remove(--m_buffer_col);
+			printf("\b\e[s%s \e[u", m_buffers[m_buffer_index].data() + m_buffer_col);
+			fflush(stdout);
+		}
+		else switch (ch)
 		{
 		case '\e':
 		{
@@ -680,6 +690,8 @@ Input::Input()
 		s_raw_termios.c_lflag &= ~(ECHO | ICANON);
 		atexit([] { tcsetattr(0, TCSANOW, &s_original_termios); });
 		s_termios_initialized = true;
+
+		m_backspace = s_original_termios.c_cc[VERASE];
 	}
 
 	char hostname_buffer[HOST_NAME_MAX];

userspace/programs/Shell/Input.h

@@ -31,5 +31,7 @@ private:
 	BAN::Optional<BAN::Vector<BAN::String>> m_tab_completions;
 	size_t m_tab_completion_keep { 0 };
 
+	char m_backspace;
+
 	int m_waiting_utf8 { 0 };
 };

userspace/programs/nologin/CMakeLists.txt

@@ -0,0 +1,9 @@
+set(SOURCES
+	main.cpp
+)
+
+add_executable(nologin ${SOURCES})
+banan_link_library(nologin ban)
+banan_link_library(nologin libc)
+
+install(TARGETS nologin OPTIONAL)

userspace/programs/nologin/main.cpp

@@ -0,0 +1,7 @@
+#include <stdio.h>
+
+int main()
+{
+	printf("This account is currently not available.\n");
+	return 1;
+}