[PATCH] pager: use an environment variable for pager_in_use

[Matthias Lederhofer <matled@gmx.net>]

When running a shell script the value of pager_in_use is
lost for later processes.  Therefore pager_in_use is
replaced by the environment variable GIT_PAGER_IN_USE.

Signed-off-by: Matthias Lederhofer <matled@gmx.net>
---

Jeff King <peff@peff.net> wrote:
> Your analysis looks right to me.  I think you would need to set
> GIT_PAGER_IN_USE in the environment whenever you turn on the pager in
> the git wrapper, and then set git's internal pager_in_use variable based
> on that.
This patch replaces pager_in_use because pager_in_use was only used at
two places (one sets it, the other reads it).
---
 cache.h       |    1 -
 color.c       |    2 +-
 environment.c |    1 -
 pager.c       |    3 ++-
 4 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/cache.h b/cache.h
index c62b0b0..aeaac9f 100644
--- a/cache.h
+++ b/cache.h
@@ -445,7 +445,6 @@ extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char
 
 /* pager.c */
 extern void setup_pager(void);
-extern int pager_in_use;
 extern int pager_use_color;
 
 /* base85 */
diff --git a/color.c b/color.c
index 09d82ee..50e073a 100644
--- a/color.c
+++ b/color.c
@@ -121,7 +121,7 @@ int git_config_colorbool(const char *var, const char *value)
 	if (!value)
 		return 1;
 	if (!strcasecmp(value, "auto")) {
-		if (isatty(1) || (pager_in_use && pager_use_color)) {
+		if (isatty(1) || (getenv("GIT_PAGER_IN_USE") && pager_use_color)) {
 			char *term = getenv("TERM");
 			if (term && strcmp(term, "dumb"))
 				return 1;
diff --git a/environment.c b/environment.c
index 54c22f8..5b477c3 100644
--- a/environment.c
+++ b/environment.c
@@ -26,7 +26,6 @@ const char *apply_default_whitespace;
 int zlib_compression_level = Z_DEFAULT_COMPRESSION;
 size_t packed_git_window_size = DEFAULT_PACKED_GIT_WINDOW_SIZE;
 size_t packed_git_limit = DEFAULT_PACKED_GIT_LIMIT;
-int pager_in_use;
 int pager_use_color = 1;
 
 static const char *git_dir;
diff --git a/pager.c b/pager.c
index 5f280ab..f59c94f 100644
--- a/pager.c
+++ b/pager.c
@@ -38,7 +38,8 @@ void setup_pager(void)
 	else if (!*pager || !strcmp(pager, "cat"))
 		return;
 
-	pager_in_use = 1; /* means we are emitting to terminal */
+	/* means we are emitting to terminal */
+	setenv("GIT_PAGER_IN_USE", "1", 0);
 
 	if (pipe(fd) < 0)
 		return;
-- 
1.5.0