untracked cache: avoid racy timestamps

diff --git a/config.c b/config.c
index e5e64dc60fa4890a99b556c31a8665b7c92375d3..66c0a51bce529e4c027f11017697a62dd737b3bd 100644 (file)
--- a/config.c
+++ b/config.c
@@ -73,8 +73,12 @@ static int config_buf_fgetc(struct config_source *conf)
 
 static int config_buf_ungetc(int c, struct config_source *conf)
 {
-       if (conf->u.buf.pos > 0)
-               return conf->u.buf.buf[--conf->u.buf.pos];
+       if (conf->u.buf.pos > 0) {
+               conf->u.buf.pos--;
+               if (conf->u.buf.buf[conf->u.buf.pos] != c)
+                       die("BUG: config_buf can only ungetc the same character");
+               return c;
+       }
 
        return EOF;
 }
@@ -235,7 +239,8 @@ static int get_next_char(void)
                /* DOS like systems */
                c = cf->do_fgetc(cf);
                if (c != '\n') {
-                       cf->do_ungetc(c, cf);
+                       if (c != EOF)
+                               cf->do_ungetc(c, cf);
                        c = '\r';
                }
        }