master 386289b 1/2: Fix 8-color PuTTY -nw sessions broken by a recent commit

[Eli Zaretskii]

branch: master
commit 386289bdc8461898b05f318b77e0bedf2509537d
Author: Eli Zaretskii <eliz@gnu.org>
Commit: Eli Zaretskii <eliz@gnu.org>

    Fix 8-color PuTTY -nw sessions broken by a recent commit
    
    * src/term.c (init_tty): Fix the change which introduced support
    for the terminfo Tc flag.  The code as installed broke colors in
    PuTTY -nw sessions, because 'tigetflag' returned -1, which is
    non-zero, so it was treated as the sign that true color is
    supported.  But if the value returned by 'tigetflag' is -1, it means
    the capability is not a boolean one, so that's not to be used as a
    valid support for 24-bit color.  (Bug#44950)
---
 src/term.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/term.c b/src/term.c
index d86ae12..51fcef6 100644
--- a/src/term.c
+++ b/src/term.c
@@ -4155,7 +4155,7 @@ use the Bourne shell command 'TERM=...; export TERM' 
(C-shell:\n\
        /* Fall back to xterm+direct (semicolon version) if Tc is set
           (de-facto standard introduced by tmux) or if requested by
           the COLORTERM environment variable.  */
-       else if (tigetflag("Tc")
+       else if ((tigetflag("Tc") != -1)
                 || ((bg = getenv("COLORTERM")) != NULL
                     && strcasecmp(bg, "truecolor") == 0))
          {