[PATCH 3/5] builtin/commit.c: use xstrdup_or_null instead of envdup

[Jeff King <peff@peff.net>]

The only reason for envdup to be its own function is that we
have to save the result in a temporary string. With
xstrdup_or_null, we can feed the result of getenv()
directly.

Signed-off-by: Jeff King <peff@peff.net>
---
These ones need the temporary. Is the result more readable, or less?

 builtin/commit.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/builtin/commit.c b/builtin/commit.c
index 7d90c35..5cd1478 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -559,20 +559,14 @@ static void set_ident_var(char **buf, char *val)
 	*buf = val;
 }
 
-static char *envdup(const char *var)
-{
-	const char *val = getenv(var);
-	return val ? xstrdup(val) : NULL;
-}
-
 static void determine_author_info(struct strbuf *author_ident)
 {
 	char *name, *email, *date;
 	struct ident_split author;
 
-	name = envdup("GIT_AUTHOR_NAME");
-	email = envdup("GIT_AUTHOR_EMAIL");
-	date = envdup("GIT_AUTHOR_DATE");
+	name = xstrdup_or_null(getenv("GIT_AUTHOR_NAME"));
+	email = xstrdup_or_null(getenv("GIT_AUTHOR_EMAIL"));
+	date = xstrdup_or_null(getenv("GIT_AUTHOR_DATE"));
 
 	if (author_message) {
 		struct ident_split ident;
-- 
2.2.1.425.g441bb3c