[PATCH 4/5] fast-export: differentiate between explicitly utf-8 and implicitly utf-8

[Elijah Newren <newren@gmail.com>]

The find_encoding() function returned the encoding used by a commit
message, returning a default of git_commit_encoding (usually utf-8).
Although the current code does not differentiate between a commit which
explicitly requested utf-8 and one where we just assume utf-8 because no
encoding is set, it will become important when we try to preserve the
encoding header.  Since is_encoding_utf8() returns true when passed
NULL, we can just return NULL from find_encoding() instead of returning
git_commit_encoding.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
 builtin/fast-export.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 7734a9f5a5..66331fa401 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -453,7 +453,7 @@ static const char *find_encoding(const char *begin, const char *end)
 	bol = memmem(begin, end ? end - begin : strlen(begin),
 		     needle, strlen(needle));
 	if (!bol)
-		return git_commit_encoding;
+		return NULL;
 	bol += strlen(needle);
 	eol = strchrnul(bol, '\n');
 	*eol = '\0';
-- 
2.21.0.779.g2f4b9c5032