From d46f476cb26f647e4571b5ccfba516d30ee06c63 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Thu, 23 Feb 2012 11:24:44 -0800 Subject: [PATCH] merge: do not trust fstat(2) too much when checking interactiveness The heuristic used by "git merge" to decide if it automatically gives an editor upon clean automerge is to see if the standard input and the standard output is the same device and is a tty, we are in an interactive session. "The same device" test was done by comparing fstat(2) result on the two file descriptors (and they must match), and we asked isatty() only for the standard input (we insist that they are the same device and there is no point asking tty-ness of the standard output). The stat(2) emulation in the Windows port however does not give a usable value in the st_ino field, so even if the standard output is connected to something different from the standard input, "The same device" test may incorrectly return true. To accomodate it, add another isatty() check for the standard output stream as well. Reported-by: Erik Faye-Lund Signed-off-by: Junio C Hamano --- builtin/merge.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/builtin/merge.c b/builtin/merge.c index ed0f959ac..d3e1e8dc9 100644 --- a/builtin/merge.c +++ b/builtin/merge.c @@ -1129,7 +1129,7 @@ static int default_edit_option(void) /* Use editor if stdin and stdout are the same and is a tty */ return (!fstat(0, &st_stdin) && !fstat(1, &st_stdout) && - isatty(0) && + isatty(0) && isatty(1) && st_stdin.st_dev == st_stdout.st_dev && st_stdin.st_ino == st_stdout.st_ino && st_stdin.st_mode == st_stdout.st_mode); -- 2.30.2