VirtualConsole: Support the 'A' and 'D' CSI sequences.

This makes backspace work correctly when line editing with bash-2.05b.

Kernel/TTY.cpp

@@ -9,16 +9,21 @@
 TTY::TTY(unsigned major, unsigned minor)
     : CharacterDevice(major, minor)
 {
-    memset(&m_termios, 0, sizeof(m_termios));
-    m_termios.c_lflag |= ISIG | ECHO;
-    static const char default_cc[32] = "\003\034\177\025\004\0\1\0\021\023\032\0\022\017\027\026\0";
-    memcpy(m_termios.c_cc, default_cc, sizeof(default_cc));
+    set_default_termios();
 }
 
 TTY::~TTY()
 {
 }
 
+void TTY::set_default_termios()
+{
+    memset(&m_termios, 0, sizeof(m_termios));
+    m_termios.c_lflag |= ISIG | ECHO;
+    static const char default_cc[32] = "\003\034\177\025\004\0\1\0\021\023\032\0\022\017\027\026\0";
+    memcpy(m_termios.c_cc, default_cc, sizeof(default_cc));
+}
+
 ssize_t TTY::read(byte* buffer, size_t size)
 {
     return m_buffer.read(buffer, size);
@@ -27,7 +32,11 @@ ssize_t TTY::read(byte* buffer, size_t size)
 ssize_t TTY::write(const byte* buffer, size_t size)
 {
 #ifdef TTY_DEBUG
-    dbgprintf("TTY::write %b    {%u}\n", buffer[0], size);
+    dbgprintf("TTY::write {%u} ", size);
+    for (size_t i = 0; i < size; ++i) {
+        dbgprintf("%b ", buffer[i]);
+    }
+    dbgprintf("\n");
 #endif
     on_tty_write(buffer, size);
     return 0;
@@ -71,12 +80,25 @@ void TTY::generate_signal(int signal)
 void TTY::set_termios(const Unix::termios& t)
 {
     m_termios = t;
-    dbgprintf("%s set_termios: IECHO? %u, ISIG? %u, ICANON? %u\n",
+    dbgprintf("%s set_termios: ECHO=%u, ISIG=%u, ICANON=%u\n",
         tty_name().characters(),
         should_echo_input(),
         should_generate_signals(),
         in_canonical_mode()
     );
+    dbgprintf("%s set_termios: ECHOE=%u, ECHOK=%u, ECHONL=%u\n",
+              tty_name().characters(),
+              (m_termios.c_lflag & ECHOE) != 0,
+              (m_termios.c_lflag & ECHOK) != 0,
+              (m_termios.c_lflag & ECHONL) != 0
+              );
+    dbgprintf("%s set_termios: ISTRIP=%u, ICRNL=%u, INLCR=%u, IGNCR=%u\n",
+              tty_name().characters(),
+              (m_termios.c_iflag & ISTRIP) != 0,
+              (m_termios.c_iflag & ICRNL) != 0,
+              (m_termios.c_iflag & INLCR) != 0,
+              (m_termios.c_iflag & IGNCR) != 0
+              );
 }
 
 int TTY::ioctl(Process& process, unsigned request, unsigned arg)

Kernel/TTY.h

@@ -29,6 +29,8 @@ public:
     bool should_echo_input() const { return m_termios.c_lflag & ECHO; }
     bool in_canonical_mode() const { return m_termios.c_lflag & ICANON; }
 
+    void set_default_termios();
+
 protected:
     virtual void on_tty_write(const byte*, size_t) = 0;
     void set_size(unsigned short columns, unsigned short rows);

Kernel/VirtualConsole.cpp

@@ -281,6 +281,17 @@ void VirtualConsole::escape$A(const Vector<unsigned>& params)
     set_cursor(new_row, m_cursor_column);
 }
 
+void VirtualConsole::escape$D(const Vector<unsigned>& params)
+{
+    int num = 1;
+    if (params.size() >= 1)
+        num = params[0];
+    int new_column = (int)m_cursor_column - num;
+    if (new_column < 0)
+        new_column = 0;
+    set_cursor(m_cursor_row, new_column);
+}
+
 void VirtualConsole::escape$J(const Vector<unsigned>& params)
 {
     int mode = 0;
@@ -319,6 +330,8 @@ void VirtualConsole::execute_escape_sequence(byte final)
         params.append(value);
     }
     switch (final) {
+    case 'A': escape$A(params); break;
+    case 'D': escape$D(params); break;
     case 'H': escape$H(params); break;
     case 'J': escape$J(params); break;
     case 'm': escape$m(params); break;

Kernel/VirtualConsole.h

@@ -41,6 +41,7 @@ private:
     void put_character_at(unsigned row, unsigned column, byte ch);
 
     void escape$A(const Vector<unsigned>&);
+    void escape$D(const Vector<unsigned>&);
     void escape$H(const Vector<unsigned>&);
     void escape$J(const Vector<unsigned>&);
     void escape$m(const Vector<unsigned>&);

LibC/termcap.cpp

@@ -114,7 +114,9 @@ char* tgoto(const char* cap, int col, int row)
 
 int tputs(const char* str, int affcnt, int (*putc)(int))
 {
-    printf("%s", str);
+    size_t len = strlen(str);
+    for (size_t i = 0; i < len; ++i)
+        putc(str[i]);
     return 0;
 }