Merge branch 'jc/diff' into next

* jc/diff:
Libify diff-index.
Libify diff-files.

diff --combined Makefile
index 25b99e62d1c891fe9d1185eb3cc7648fe811835a,0924f84c4f8b964b18e97670ad8d407f99f08ecf..c1778560ee2999a8276d904d639ff783a78d1784
--- 1/Makefile
--- 2/Makefile
+++ b/Makefile
@@@ -199,7 -199,7 +199,7 @@@ LIB_H = 
        tree-walk.h log-tree.h
  
  DIFF_OBJS = \
-       diff-lib.o diffcore-break.o diffcore-order.o \
+       diff.o diff-lib.o diffcore-break.o diffcore-order.o \
        diffcore-pickaxe.o diffcore-rename.o tree-diff.o combine-diff.o \
        diffcore-delta.o log-tree.o
  
@@@ -611,9 -611,6 +611,9 @@@ test-date$X: test-date.c date.o ctype.
  test-delta$X: test-delta.c diff-delta.o patch-delta.o
        $(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $^ -lz
  
 +test-gsimm$X: test-gsimm.c gsimm.o rabinpoly.o
 +      $(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $^
 +
  check:
        for i in *.c; do sparse $(ALL_CFLAGS) $(SPARSE_FLAGS) $$i || exit; done
  
@@@ -662,7 -659,6 +662,7 @@@ clean
        rm -f *.o mozilla-sha1/*.o arm/*.o ppc/*.o compat/*.o xdiff/*.o \
                $(LIB_FILE) $(XDIFF_LIB)
        rm -f $(ALL_PROGRAMS) $(BUILT_INS) git$X
 +      rm -f test-date$X test-delta$X test-gsimm$X
        rm -f *.spec *.pyc *.pyo */*.pyc */*.pyo common-cmds.h TAGS tags
        rm -rf $(GIT_TARNAME)
        rm -f $(GIT_TARNAME).tar.gz git-core_$(GIT_VERSION)-*.tar.gz