[systemd-devel] [PATCH] vconsole: set font on tty16..tty63 as well

[Jan Engelhardt]

The setup program would not set the font on tty16 and upwards.
There is a maximum of 63 VCs possible in Linux. (That number is
hardcoded.)

The reason for systemd not having supported tty16+ is because it
used the VT_GETSTATE ioctl, which can only tell about the state
of the first 16 ttys. However,

However, it also seems that we do not need to rely on this
state mask. /dev/vcsN is present if it is active, and is
absent when deallocated -- at least if one is using a dynamically
managed /dev, which I suppose is a requirement of systemd anyway.
---
 src/vconsole/vconsole-setup.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/vconsole/vconsole-setup.c b/src/vconsole/vconsole-setup.c
index bf681d9..d43b69f 100644
--- a/src/vconsole/vconsole-setup.c
+++ b/src/vconsole/vconsole-setup.c
@@ -181,20 +181,21 @@ static void font_copy_to_all_vcs(int fd) {
         struct unipair unipairs[USHRT_MAX];
         int i, r;
 
-        /* get active, and 16 bit mask of used VT numbers */
+        /* get active tty - ignore v_state bitmask */
         r = ioctl(fd, VT_GETSTATE, &vcs);
         if (r < 0)
                 return;
 
-        for (i = 1; i <= 15; i++) {
+        for (i = 1; i < 64; ++i) {
                 char vcname[16];
                 _cleanup_close_ int vcfd = -1;
                 struct console_font_op cfo = {};
 
-                if (i == vcs.v_active)
-                        continue;
-
-                /* skip non-allocated ttys */
+                /*
+                 * Skip non-allocated ttys. Rather than using the 16-bit-only
+                 * vcs.v_state, look at the presence of the device file to
+                 * determine whether it is active or not.
+                 */
                 snprintf(vcname, sizeof(vcname), "/dev/vcs%i", i);
                 if (access(vcname, F_OK) < 0)
                         continue;
-- 
2.1.4