Merge branch 'sb/submodule-recursive-absorb'

When a submodule "A", which has another submodule "B" nested within
it, is "absorbed" into the top-level superproject, the inner
submodule "B" used to be left in a strange state.  The logic to
adjust the .git pointers in these submodules has been corrected.

* sb/submodule-recursive-absorb:
submodule absorbing: fix worktree/gitdir pointers recursively for non-moves
cache.h: expose the dying procedure for reading gitlinks
setup: add gentle version of resolve_git_dir

diff --combined cache.h
index 8c77b8c543269a3f2c0b3e4149830f79176fccde,d55f5dccb17ea782c33437a4af1e44a6bedffb1d..e26566a8ec3f9aae6547da4303ad62c013146208
--- 1/cache.h
--- 2/cache.h
+++ b/cache.h
@@@ -507,9 -507,12 +507,12 @@@ extern int is_nonbare_repository_dir(st
  #define READ_GITFILE_ERR_NO_PATH 6
  #define READ_GITFILE_ERR_NOT_A_REPO 7
  #define READ_GITFILE_ERR_TOO_LARGE 8
+ extern void read_gitfile_error_die(int error_code, const char *path, const char *dir);
  extern const char *read_gitfile_gently(const char *path, int *return_error_code);
  #define read_gitfile(path) read_gitfile_gently((path), NULL)
- extern const char *resolve_gitdir(const char *suspect);
+ extern const char *resolve_gitdir_gently(const char *suspect, int *return_error_code);
+ #define resolve_gitdir(path) resolve_gitdir_gently((path), NULL)
+ 
  extern void set_git_work_tree(const char *tree);
  
  #define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
@@@ -574,26 -577,7 +577,26 @@@ extern int verify_path(const char *path
  extern int index_dir_exists(struct index_state *istate, const char *name, int namelen);
  extern void adjust_dirname_case(struct index_state *istate, char *name);
  extern struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 +
 +/*
 + * Searches for an entry defined by name and namelen in the given index.
 + * If the return value is positive (including 0) it is the position of an
 + * exact match. If the return value is negative, the negated value minus 1
 + * is the position where the entry would be inserted.
 + * Example: The current index consists of these files and its stages:
 + *
 + *   b#0, d#0, f#1, f#3
 + *
 + * index_name_pos(&index, "a", 1) -> -1
 + * index_name_pos(&index, "b", 1) ->  0
 + * index_name_pos(&index, "c", 1) -> -2
 + * index_name_pos(&index, "d", 1) ->  1
 + * index_name_pos(&index, "e", 1) -> -3
 + * index_name_pos(&index, "f", 1) -> -3
 + * index_name_pos(&index, "g", 1) -> -5
 + */
  extern int index_name_pos(const struct index_state *, const char *name, int namelen);
 +
  #define ADD_CACHE_OK_TO_ADD 1         /* Ok to add */
  #define ADD_CACHE_OK_TO_REPLACE 2     /* Ok to replace file/directory */
  #define ADD_CACHE_SKIP_DFCHECK 4      /* Ok to skip DF conflict checks */
@@@ -602,10 -586,7 +605,10 @@@
  #define ADD_CACHE_KEEP_CACHE_TREE 32  /* Do not invalidate cache-tree */
  extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
  extern void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
 +
 +/* Remove entry, return true if there are more entries to go. */
  extern int remove_index_entry_at(struct index_state *, int pos);
 +
  extern void remove_marked_cache_entries(struct index_state *istate);
  extern int remove_file_from_index(struct index_state *, const char *path);
  #define ADD_CACHE_VERBOSE 1
@@@ -613,18 -594,8 +616,18 @@@
  #define ADD_CACHE_IGNORE_ERRORS       4
  #define ADD_CACHE_IGNORE_REMOVAL 8
  #define ADD_CACHE_INTENT 16
 +/*
 + * These two are used to add the contents of the file at path
 + * to the index, marking the working tree up-to-date by storing
 + * the cached stat info in the resulting cache entry.  A caller
 + * that has already run lstat(2) on the path can call
 + * add_to_index(), and all others can call add_file_to_index();
 + * the latter will do necessary lstat(2) internally before
 + * calling the former.
 + */
  extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
  extern int add_file_to_index(struct index_state *, const char *path, int flags);
 +
  extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, unsigned int refresh_options);
  extern int chmod_index_entry(struct index_state *, struct cache_entry *ce, char flip);
  extern int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
@@@ -1101,7 -1072,6 +1104,7 @@@ const char *real_path(const char *path)
  const char *real_path_if_valid(const char *path);
  char *real_pathdup(const char *path);
  const char *absolute_path(const char *path);
 +char *absolute_pathdup(const char *path);
  const char *remove_leading_path(const char *in, const char *prefix);
  const char *relative_path(const char *in, const char *prefix, struct strbuf *sb);
  int normalize_path_copy_len(char *dst, const char *src, int *prefix_len);
@@@ -1175,19 -1145,6 +1178,19 @@@ extern int finalize_object_file(const c
  
  extern int has_sha1_pack(const unsigned char *sha1);
  
 +/*
 + * Open the loose object at path, check its sha1, and return the contents,
 + * type, and size. If the object is a blob, then "contents" may return NULL,
 + * to allow streaming of large blobs.
 + *
 + * Returns 0 on success, negative on error (details may be written to stderr).
 + */
 +int read_loose_object(const char *path,
 +                    const unsigned char *expected_sha1,
 +                    enum object_type *type,
 +                    unsigned long *size,
 +                    void **contents);
 +
  /*
   * Return true iff we have an object named sha1, whether local or in
   * an alternate object database, and whether packed or loose.  This