lib/colors: force to "never" mode on non-terminal output

Signed-off-by: Karel Zak <kzak@redhat.com>

include/colors.h

@@ -38,6 +38,9 @@ extern int colors_init(int mode, const char *util_name);
 /* Returns 1 or 0 */
 extern int colors_wanted(void);
 
+/* Returns UL_COLORMODE_* */
+extern int colors_mode(void);
+
 /* temporary enable/disable colors */
 extern void colors_off(void);
 extern void colors_on(void);

lib/colors.c

@@ -653,9 +653,6 @@ static int colors_terminal_is_ready(void)
 {
 	int ncolors = -1;
 
-	if (isatty(STDOUT_FILENO) != 1)
-		goto none;
-
 #if defined(HAVE_LIBNCURSES) || defined(HAVE_LIBNCURSESW)
 	{
 		int ret;
@@ -692,11 +689,16 @@ int colors_init(int mode, const char *name)
 	struct ul_color_ctl *cc = &ul_colors;
 
 	cc->utilname = name;
-	cc->mode = mode;
 
 	termcolors_init_debug();
 
-	if (mode == UL_COLORMODE_UNDEF && (ready = colors_terminal_is_ready())) {
+	if (mode != UL_COLORMODE_ALWAYS && !isatty(STDOUT_FILENO))
+		cc->mode = UL_COLORMODE_NEVER;
+	else
+		cc->mode = mode;
+
+	if (cc->mode == UL_COLORMODE_UNDEF
+	    && (ready = colors_terminal_is_ready())) {
 		int rc = colors_read_configuration(cc);
 		if (rc)
 			cc->mode = UL_COLORMODE_DEFAULT;
@@ -754,6 +756,14 @@ int colors_wanted(void)
 	return ul_colors.has_colors;
 }
 
+/*
+ * Returns mode
+ */
+int colors_mode(void)
+{
+	return ul_colors.mode;
+}
+
 /*
  * Enable @seq color
  */