[PATCH] Redo rename/copy detection logic.

Earlier implementation had a major screw-up in the memory
management area.  Rename/copy logic sometimes borrowed a pointer
to a structure without any provision for downstream to determine
which pointer is shared and which is not.  This resulted in the
later clean-up code to sometimes double free such structure,
resulting in a segfault.  This made -M and -C useless.

Another problem the earlier implementation had was that it
reordered the patches, and forced the logic to differentiate
renames and copies to depend on that particular order.  This
problem was fixed by teaching rename/copy detection logic not to
do any reordering, and rename-copy differentiator not to depend
on the order of the patches.  The diffs will leave rename/copy
detector in the same destination path order as the patch that
was fed into it.  Some test vectors have been reordered to
accommodate this change.

It also adds a sanity check logic to the human-readable diff-raw
output to detect paths with embedded TAB and LF characters,
which cannot be expressed with that format.  This idea came up
during a discussion with Chris Wedgwood.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 24 insertions, 24 deletions

diff --git a/t/t4003-diff-rename-1.sh b/t/t4003-diff-rename-1.sh
index 9d0e22e17a..c5f325577d 100644
--- a/t/t4003-diff-rename-1.sh
+++ b/t/t4003-diff-rename-1.sh
@@ -78,14 +78,6 @@ test_expect_success \
 
 GIT_DIFF_OPTS=--unified=0 git-diff-cache -C -p $tree >current
 cat >expected <<\EOF
-diff --git a/COPYING b/COPYING.1
-copy from COPYING
-copy to COPYING.1
---- a/COPYING
-+++ b/COPYING.1
-@@ -6 +6 @@
-- HOWEVER, in order to allow a migration to GPLv3 if that seems like
-+ However, in order to allow a migration to GPLv3 if that seems like
 diff --git a/COPYING b/COPYING
 --- a/COPYING
 +++ b/COPYING
@@ -98,6 +90,14 @@ diff --git a/COPYING b/COPYING
 @@ -12 +12 @@
 -	This file is licensed under the GPL v2, or a later version
 +	This file is licensed under the G.P.L v2, or a later version
+diff --git a/COPYING b/COPYING.1
+copy from COPYING
+copy to COPYING.1
+--- a/COPYING
++++ b/COPYING.1
+@@ -6 +6 @@
+- HOWEVER, in order to allow a migration to GPLv3 if that seems like
++ However, in order to allow a migration to GPLv3 if that seems like
 EOF
 
 test_expect_success \
diff --git a/t/t4004-diff-rename-symlink.sh b/t/t4004-diff-rename-symlink.sh
index 31fdc50653..eb6dedd1ca 100644
--- a/t/t4004-diff-rename-symlink.sh
+++ b/t/t4004-diff-rename-symlink.sh
@@ -35,6 +35,13 @@ test_expect_success \
 
 GIT_DIFF_OPTS=--unified=0 git-diff-cache -M -p $tree >current
 cat >expected <<\EOF
+diff --git a/bozbar b/bozbar
+new file mode 120000
+--- /dev/null
++++ b/bozbar
+@@ -0,0 +1 @@
++xzzzy
+\ No newline at end of file
 diff --git a/frotz b/nitfol
 similarity index 100%
 copy from frotz
@@ -50,13 +57,6 @@ deleted file mode 100644
 @@ -1 +0,0 @@
 -xyzzy
 \ No newline at end of file
-diff --git a/bozbar b/bozbar
-new file mode 120000
---- /dev/null
-+++ b/bozbar
-@@ -0,0 +1 @@
-+xzzzy
-\ No newline at end of file
 EOF
 
 test_expect_success \
diff --git a/t/t4005-diff-rename-2.sh b/t/t4005-diff-rename-2.sh
index 24d5365aa8..a519855182 100644
--- a/t/t4005-diff-rename-2.sh
+++ b/t/t4005-diff-rename-2.sh
@@ -101,8 +101,8 @@ test_expect_success \
 
 git-diff-cache -C $tree >current
 cat >expected <<\EOF
-:100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 0603b3238a076dc6c8022aedc6648fa523a17178 C1234	COPYING	COPYING.1
 :100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 06c67961bbaed34a127f76d261f4c0bf73eda471 M	COPYING
+:100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 0603b3238a076dc6c8022aedc6648fa523a17178 C1234	COPYING	COPYING.1
 EOF
 
 test_expect_success \
@@ -118,14 +118,6 @@ test_expect_success \
 mv expected diff-raw
 GIT_DIFF_OPTS=--unified=0 git-diff-helper <diff-raw >current
 cat >expected <<\EOF
-diff --git a/COPYING b/COPYING.1
-copy from COPYING
-copy to COPYING.1
---- a/COPYING
-+++ b/COPYING.1
-@@ -6 +6 @@
-- HOWEVER, in order to allow a migration to GPLv3 if that seems like
-+ However, in order to allow a migration to GPLv3 if that seems like
 diff --git a/COPYING b/COPYING
 --- a/COPYING
 +++ b/COPYING
@@ -138,6 +130,14 @@ diff --git a/COPYING b/COPYING
 @@ -12 +12 @@
 -	This file is licensed under the GPL v2, or a later version
 +	This file is licensed under the G.P.L v2, or a later version
+diff --git a/COPYING b/COPYING.1
+copy from COPYING
+copy to COPYING.1
+--- a/COPYING
++++ b/COPYING.1
+@@ -6 +6 @@
+- HOWEVER, in order to allow a migration to GPLv3 if that seems like
++ However, in order to allow a migration to GPLv3 if that seems like
 EOF
 
 test_expect_success \