verify-commit: scriptable commit signature verification

Commit signatures can be verified using "git show -s --show-signature"
or the "%G?" pretty format and parsing the output, which is well suited
for user inspection, but not for scripting.

Provide a command "verify-commit" which is analogous to "verify-tag": It
returns 0 for good signatures and non-zero otherwise, has the gpg output
on stderr and (optionally) the commit object on stdout, sans the
signature, just like "verify-tag" does.

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index 07ea10583..b92418de7 100644
--- a/Makefile
+++ b/Makefile
@@ -999,6 +999,7 @@ BUILTIN_OBJS += builtin/update-ref.o
 BUILTIN_OBJS += builtin/update-server-info.o
 BUILTIN_OBJS += builtin/upload-archive.o
 BUILTIN_OBJS += builtin/var.o
+BUILTIN_OBJS += builtin/verify-commit.o
 BUILTIN_OBJS += builtin/verify-pack.o
 BUILTIN_OBJS += builtin/verify-tag.o
 BUILTIN_OBJS += builtin/write-tree.o