From 04f788023fd04e60a12c2a19787857c72b3817f4 Mon Sep 17 00:00:00 2001
From: Brodie Rao <brodie@bitheap.org>
Date: Tue, 9 Aug 2011 20:49:12 -0700
Subject: [PATCH] commit: properly parse empty commit messages

This ensures commit->message is always non-NULL, even if the commit
message is empty or consists of only a newline.

One such commit can be found in the wild in the jQuery repository:

https://github.com/jquery/jquery/commit/25b424134f9927a5bf0bab5cba836a0aa6c3cfc1
---
 src/commit.c                                      |   4 ++--
 .../36/97d64be941a53d4ae8f6a271e4e3fa56b022cc     | Bin 0 -> 23 bytes
 .../94/4c0f6e4dfa41595e6eb3ceecdb14f50fe18162     | Bin 0 -> 119 bytes
 .../a6/5fedf39aefe402d3bb6e24df4d4f5fe4547750     | Bin 0 -> 150 bytes
 tests/resources/testrepo.git/refs/heads/master    | Bin 41 -> 41 bytes
 tests/t04-commit.c                                |   2 ++
 tests/t10-refs.c                                  |   2 +-
 7 files changed, 5 insertions(+), 3 deletions(-)
 create mode 100644 tests/resources/testrepo.git/objects/36/97d64be941a53d4ae8f6a271e4e3fa56b022cc
 create mode 100644 tests/resources/testrepo.git/objects/94/4c0f6e4dfa41595e6eb3ceecdb14f50fe18162
 create mode 100644 tests/resources/testrepo.git/objects/a6/5fedf39aefe402d3bb6e24df4d4f5fe4547750

diff --git a/src/commit.c b/src/commit.c
index 0ee3854c4..ced457ecc 100644
--- a/src/commit.c
+++ b/src/commit.c
@@ -221,10 +221,10 @@ int git_commit__parse_buffer(git_commit *commit, const void *data, size_t len)
 	}
 
 	/* parse commit message */
-	while (buffer < buffer_end && *buffer == '\n')
+	while (buffer < buffer_end - 1 && *buffer == '\n')
 		buffer++;
 
-	if (buffer < buffer_end) {
+	if (buffer <= buffer_end) {
 		commit->message = git__strndup(buffer, buffer_end - buffer);
 		if (!commit->message)
 			return GIT_ENOMEM;
diff --git a/tests/resources/testrepo.git/objects/36/97d64be941a53d4ae8f6a271e4e3fa56b022cc b/tests/resources/testrepo.git/objects/36/97d64be941a53d4ae8f6a271e4e3fa56b022cc
new file mode 100644
index 0000000000000000000000000000000000000000..9bb5b623bdbc11a70db482867b5b26d0d7b3215c
GIT binary patch
literal 23
fcmb<m^geacKWIb3i4#w}R{4ZJVPa5KVX*@Mf$Ir_

literal 0
HcmV?d00001

diff --git a/tests/resources/testrepo.git/objects/94/4c0f6e4dfa41595e6eb3ceecdb14f50fe18162 b/tests/resources/testrepo.git/objects/94/4c0f6e4dfa41595e6eb3ceecdb14f50fe18162
new file mode 100644
index 0000000000000000000000000000000000000000..4cc3f4dffc37fc2b5aed8f0e607edb7441d3d38d
GIT binary patch
literal 119
zcmV--0Eqv10V^p=O;s>7G-5C`FfcPQQ3!H%bn$g%SfOmF@NI2De~WFK%%kl}eMcVO
zI|fyeRFs&PoDrXvnUktlQc=QSHvO9SOUI?QUN62aDtz+zSJ(!nGf<^@spViL%SGD`
Z-hZ)NCTD++(0m7<FsJ{9djZppF<94jHgy01

literal 0
HcmV?d00001

diff --git a/tests/resources/testrepo.git/objects/a6/5fedf39aefe402d3bb6e24df4d4f5fe4547750 b/tests/resources/testrepo.git/objects/a6/5fedf39aefe402d3bb6e24df4d4f5fe4547750
new file mode 100644
index 0000000000000000000000000000000000000000..29c8e824d2b2e0094cb55398f1d2a374e38d6437
GIT binary patch
literal 150
zcmV;H0BQet0iBLf3IZVzK>PL-bAdvgQ4=D9j?f9l*|80Bjm_@g(h>T5Jb3V=xAqv|
z9qz`e3Ykc3jY?Bxav=weT2NGFDvoNfRo&4=Z(h9WGN34ih^$ys4#gM3fJH=+gHJqJ
zrkZLbGW;2HU*RTw47koLeSy<kesH-remoD-+Zh}>p9!Onu(!!tv)S!%=s&G7U;E`l
EFjbjGl>h($

literal 0
HcmV?d00001

diff --git a/tests/resources/testrepo.git/refs/heads/master b/tests/resources/testrepo.git/refs/heads/master
index 9536ad89cfb3b156e2ad6bafe06c6a708d7d2b73..3d8f0a402b492c248b12ac72b6a66eebe941023f 100644
GIT binary patch
literal 41
vcmYc^GfhiPNi()gOifEQF)&IoPD(OMH8M#_Gf6Q?1In40nwXoL8gKys2{Q}F

literal 41
ucmV~$!4Uu;2m`Rc(|EMVIZi>?e*}|k_<<S|*VB@4WK~0Mp|{0}Ipq5Ek_%P<

diff --git a/tests/t04-commit.c b/tests/t04-commit.c
index 88c7efd81..58d24bf73 100644
--- a/tests/t04-commit.c
+++ b/tests/t04-commit.c
@@ -560,6 +560,7 @@ static const char *commit_ids[] = {
 	"c47800c7266a2be04c571c04d5a6614691ea99bd", /* 3 */
 	"8496071c1b46c854b31185ea97743be6a8774479", /* 4 */
 	"5b5b025afb0b4c913b4c338a42934a3863bf3644", /* 5 */
+	"a65fedf39aefe402d3bb6e24df4d4f5fe4547750", /* 6 */
 };
 
 BEGIN_TEST(details0, "query the details on a parsed commit")
@@ -594,6 +595,7 @@ BEGIN_TEST(details0, "query the details on a parsed commit")
 		must_be_true(strcmp(author->email, "schacon@gmail.com") == 0);
 		must_be_true(strcmp(committer->name, "Scott Chacon") == 0);
 		must_be_true(strcmp(committer->email, "schacon@gmail.com") == 0);
+		must_be_true(message != NULL);
 		must_be_true(strchr(message, '\n') != NULL);
 		must_be_true(commit_time > 0);
 		must_be_true(parents <= 2);
diff --git a/tests/t10-refs.c b/tests/t10-refs.c
index 67034155d..1b3e0a3aa 100644
--- a/tests/t10-refs.c
+++ b/tests/t10-refs.c
@@ -70,7 +70,7 @@ END_TEST
 
 static const char *head_tracker_sym_ref_name = "head-tracker";
 static const char *current_head_target = "refs/heads/master";
-static const char *current_master_tip = "be3563ae3f795b2b4353bcce3a527ad0a4f7f644";
+static const char *current_master_tip = "a65fedf39aefe402d3bb6e24df4d4f5fe4547750";
 
 BEGIN_TEST(readsym0, "lookup a symbolic reference")
 	git_repository *repo;