tty: vt: define an enum for ascii characters

I didn't find definitions for ascii in the kernel yet, so define it for
non-printable characters used here.

Note we use ' ' instead of 32 on one line too.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-18-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 8d868aa337332047321b834630fdc1263cc32559..51a2787415dbfd1f834d2e116098c445c634db0d 100644 (file)
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -2143,6 +2143,28 @@ static bool ansi_control_string(unsigned int state)
        return false;
 }
 
+enum {
+       ASCII_NULL              = 0,
+       ASCII_BELL              = 7,
+       ASCII_BACKSPACE         = 8,
+       ASCII_IGNORE_FIRST      = ASCII_BACKSPACE,
+       ASCII_HTAB              = 9,
+       ASCII_LINEFEED          = 10,
+       ASCII_VTAB              = 11,
+       ASCII_FORMFEED          = 12,
+       ASCII_CAR_RET           = 13,
+       ASCII_IGNORE_LAST       = ASCII_CAR_RET,
+       ASCII_SHIFTOUT          = 14,
+       ASCII_SHIFTIN           = 15,
+       ASCII_CANCEL            = 24,
+       ASCII_SUBSTITUTE        = 26,
+       ASCII_ESCAPE            = 27,
+       ASCII_CSI_IGNORE_FIRST  = ' ', /* 0x2x, 0x3a and 0x3c - 0x3f */
+       ASCII_CSI_IGNORE_LAST   = '?',
+       ASCII_DEL               = 127,
+       ASCII_EXT_CSI           = 128 + ASCII_ESCAPE,
+};
+
 /* console_lock is held */
 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
 {
@@ -2150,21 +2172,22 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
         *  Control characters can be used in the _middle_
         *  of an escape sequence, aside from ANSI control strings.
         */
-       if (ansi_control_string(vc->vc_state) && c >= 8 && c <= 13)
+       if (ansi_control_string(vc->vc_state) && c >= ASCII_IGNORE_FIRST &&
+           c <= ASCII_IGNORE_LAST)
                return;
        switch (c) {
-       case 0:
+       case ASCII_NULL:
                return;
-       case 7:
+       case ASCII_BELL:
                if (ansi_control_string(vc->vc_state))
                        vc->vc_state = ESnormal;
                else if (vc->vc_bell_duration)
                        kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
                return;
-       case 8:
+       case ASCII_BACKSPACE:
                bs(vc);
                return;
-       case 9:
+       case ASCII_HTAB:
                vc->vc_pos -= (vc->state.x << 1);
 
                vc->state.x = find_next_bit(vc->vc_tab_stop,
@@ -2176,34 +2199,37 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
                vc->vc_pos += (vc->state.x << 1);
                notify_write(vc, '\t');
                return;
-       case 10: case 11: case 12:
+       case ASCII_LINEFEED:
+       case ASCII_VTAB:
+       case ASCII_FORMFEED:
                lf(vc);
                if (!is_kbd(vc, lnm))
                        return;
                fallthrough;
-       case 13:
+       case ASCII_CAR_RET:
                cr(vc);
                return;
-       case 14:
+       case ASCII_SHIFTOUT:
                vc->state.charset = 1;
                vc->vc_translate = set_translate(vc->state.Gx_charset[1], vc);
                vc->vc_disp_ctrl = 1;
                return;
-       case 15:
+       case ASCII_SHIFTIN:
                vc->state.charset = 0;
                vc->vc_translate = set_translate(vc->state.Gx_charset[0], vc);
                vc->vc_disp_ctrl = 0;
                return;
-       case 24: case 26:
+       case ASCII_CANCEL:
+       case ASCII_SUBSTITUTE:
                vc->vc_state = ESnormal;
                return;
-       case 27:
+       case ASCII_ESCAPE:
                vc->vc_state = ESesc;
                return;
-       case 127:
+       case ASCII_DEL:
                del(vc);
                return;
-       case 128+27:
+       case ASCII_EXT_CSI:
                vc->vc_state = ESsquare;
                return;
        }
@@ -2338,7 +2364,7 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
                        vc->vc_par[vc->vc_npar] += c - '0';
                        return;
                }
-               if (c >= 0x20 && c <= 0x3f) { /* 0x2x, 0x3a and 0x3c - 0x3f */
+               if (c >= ASCII_CSI_IGNORE_FIRST && c <= ASCII_CSI_IGNORE_LAST) {
                        vc->vc_state = EScsiignore;
                        return;
                }
@@ -2500,7 +2526,7 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
                }
                return;
        case EScsiignore:
-               if (c >= 0x20 && c <= 0x3f)
+               if (c >= ASCII_CSI_IGNORE_FIRST && c <= ASCII_CSI_IGNORE_LAST)
                        return;
                vc->vc_state = ESnormal;
                return;
@@ -2761,17 +2787,17 @@ static bool vc_is_control(struct vc_data *vc, int tc, int c)
         * useless without them; to display an arbitrary font position use the
         * direct-to-font zone in UTF-8 mode.
         */
-       if (c < 32) {
+       if (c < ' ') {
                if (vc->vc_disp_ctrl)
                        return CTRL_ALWAYS & BIT(c);
                else
                        return vc->vc_utf || (CTRL_ACTION & BIT(c));
        }
 
-       if (c == 127 && !vc->vc_disp_ctrl)
+       if (c == ASCII_DEL && !vc->vc_disp_ctrl)
                return true;
 
-       if (c == 128 + 27)
+       if (c == ASCII_EXT_CSI)
                return true;
 
        return false;