setup_pager: set GIT_PAGER_IN_USE

We have always set a global "spawned_pager" variable when we
start the pager. This lets us make the auto-color decision
later in the program as as "we are outputting to a terminal,
or to a pager which can handle colors".

Commit 6e9af86 added support for the GIT_PAGER_IN_USE
environment variable. An external program calling git (e.g.,
git-svn) could set this variable to indicate that it had
already started the pager, and that the decision about
auto-coloring should take that into account.

However, 6e9af86 failed to do the reverse, which is to tell
external programs when git itself has started the pager.
Thus a git command implemented as an external script that
has the pager turned on (e.g., "git -p stash show") would
not realize it was going to a pager, and would suppress
colors.

This patch remedies that; we always set GIT_PAGER_IN_USE
when we start the pager, and the value is respected by both
this program and any spawned children.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 7 deletions

diff --git a/pager.c b/pager.c
index dac358f..975955b 100644
--- a/pager.c
+++ b/pager.c
@@ -11,8 +11,6 @@
  * something different on Windows.
  */
 
-static int spawned_pager;
-
 #ifndef WIN32
 static void pager_preexec(void)
 {
@@ -78,7 +76,7 @@ void setup_pager(void)
 	if (!pager)
 		return;
 
-	spawned_pager = 1; /* means we are emitting to terminal */
+	setenv("GIT_PAGER_IN_USE", "true", 1);
 
 	/* spawn the pager */
 	pager_argv[0] = pager;
@@ -109,10 +107,6 @@ void setup_pager(void)
 int pager_in_use(void)
 {
 	const char *env;
-
-	if (spawned_pager)
-		return 1;
-
 	env = getenv("GIT_PAGER_IN_USE");
 	return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0;
 }