Merge part of 'jc/diff' into next

diff --combined Makefile
index 26ef1f81044caccaab2cee96d7facdf3b9e2df83,a5eb0c4beb9b7d65e321fde5634904d42331dbd0..db07d4d451f769bb855e58c12ce64cb403e08c63
--- 1/Makefile
--- 2/Makefile
+++ b/Makefile
@@@ -165,7 -165,7 +165,7 @@@ PROGRAMS = 
        git-upload-pack$X git-verify-pack$X git-write-tree$X \
        git-update-ref$X git-symbolic-ref$X git-check-ref-format$X \
        git-name-rev$X git-pack-redundant$X git-repo-config$X git-var$X \
 -      git-describe$X git-merge-tree$X
 +      git-describe$X git-merge-tree$X git-blame$X
  
  # what 'all' will build and 'install' will install, in gitexecdir
  ALL_PROGRAMS = $(PROGRAMS) $(SIMPLE_PROGRAMS) $(SCRIPTS)
@@@ -192,11 -192,12 +192,12 @@@ LIB_FILE=libgit.
  LIB_H = \
        blob.h cache.h commit.h count-delta.h csum-file.h delta.h \
        diff.h epoch.h object.h pack.h pkt-line.h quote.h refs.h \
 -      run-command.h strbuf.h tag.h tree.h git-compat-util.h
 +      run-command.h strbuf.h tag.h tree.h git-compat-util.h revision.h
  
  DIFF_OBJS = \
        diff.o diffcore-break.o diffcore-order.o diffcore-pathspec.o \
-       diffcore-pickaxe.o diffcore-rename.o tree-diff.o combine-diff.o
+       diffcore-pickaxe.o diffcore-rename.o tree-diff.o combine-diff.o \
+       diffcore-delta.o
  
  LIB_OBJS = \
        blob.o commit.o connect.o count-delta.o csum-file.o \
@@@ -205,7 -206,7 +206,7 @@@
        quote.o read-cache.o refs.o run-command.o \
        server-info.o setup.o sha1_file.o sha1_name.o strbuf.o \
        tag.o tree.o usage.o config.o environment.o ctype.o copy.o \
 -      fetch-clone.o \
 +      fetch-clone.o revision.o \
        $(DIFF_OBJS)
  
  LIBS = $(LIB_FILE)

diff --combined diffcore.h
index 91d6c631e69a1f628fa65feecab1ee8b1fb73fad,dba4f17658e6b3b7e1853ca024f8cfe9eae9c92e..7f9889daf375a0c310fddefeffa0bad5f4d1393c
--- 1/diffcore.h
--- 2/diffcore.h
+++ b/diffcore.h
@@@ -18,7 -18,7 +18,7 @@@
  #define MAX_SCORE 60000.0
  #define DEFAULT_RENAME_SCORE 30000 /* rename/copy similarity minimum (50%) */
  #define DEFAULT_BREAK_SCORE  30000 /* minimum for break to happen (50%)*/
 -#define DEFAULT_MERGE_SCORE  48000 /* maximum for break-merge to happen (80%)*/
 +#define DEFAULT_MERGE_SCORE  45000 /* maximum for break-merge to happen (75%)*/
  
  #define MINIMUM_BREAK_SIZE     400 /* do not break a file smaller than this */
  
@@@ -101,4 -101,10 +101,10 @@@ void diff_debug_queue(const char *, str
  #define diff_debug_queue(a,b) do {} while(0)
  #endif
  
+ extern int diffcore_count_changes(void *src, unsigned long src_size,
+                                 void *dst, unsigned long dst_size,
+                                 unsigned long delta_limit,
+                                 unsigned long *src_copied,
+                                 unsigned long *literal_added);
+ 
  #endif