terminal-util: use getenv_bool for $SYSTEMD_COLORS

This changes the semantics a bit: before, SYSTEMD_COLORS= would be treated as
"yes", same as SYSTEMD_COLORS=xxx and SYSTEMD_COLORS=1, and only
SYSTEMD_COLORS=0 would be treated as "no". Now, only valid booleans are treated
as "yes". This actually matches how $SYSTEMD_COLORS was announced in NEWS.

diff --git a/src/basic/terminal-util.c b/src/basic/terminal-util.c
index 59fac9c0c2ab361f486e00ce94f60076d435c519..215b764882b95dbde54dc09b599b0a948776de1f 100644 (file)
--- a/src/basic/terminal-util.c
+++ b/src/basic/terminal-util.c
@@ -1224,11 +1224,11 @@ bool colors_enabled(void) {
         static int enabled = -1;
 
         if (_unlikely_(enabled < 0)) {
-                const char *colors;
+                int val;
 
-                colors = getenv("SYSTEMD_COLORS");
-                if (colors)
-                        enabled = parse_boolean(colors) != 0;
+                val = getenv_bool("SYSTEMD_COLORS");
+                if (val >= 0)
+                        enabled = val;
                 else if (getpid() == 1)
                         /* PID1 outputs to the console without holding it open all the time */
                         enabled = !getenv_terminal_is_dumb();