diff --git a/git2/frameworks/libgit2.0.17.0.dylib b/git2/frameworks/libgit2.0.17.0.dylib
index 933ca3765..6cee2cf63 100755
Binary files a/git2/frameworks/libgit2.0.17.0.dylib and b/git2/frameworks/libgit2.0.17.0.dylib differ
diff --git a/git2/include/git2.h b/git2/include/git2.h
index e138e279a..5f9fc4824 100644
--- a/git2/include/git2.h
+++ b/git2/include/git2.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/attr.h b/git2/include/git2/attr.h
index b1a7e0eb6..dea44f0e3 100644
--- a/git2/include/git2/attr.h
+++ b/git2/include/git2/attr.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/blob.h b/git2/include/git2/blob.h
index 30055b614..0c0f3e580 100644
--- a/git2/include/git2/blob.h
+++ b/git2/include/git2/blob.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -91,7 +91,7 @@ GIT_INLINE(const git_oid *) git_blob_id(const git_blob *blob)
  * @param blob pointer to the blob
  * @return the pointer; NULL if the blob has no contents
  */
-GIT_EXTERN(const void *) git_blob_rawcontent(git_blob *blob);
+GIT_EXTERN(const void *) git_blob_rawcontent(const git_blob *blob);
 
 /**
  * Get the size in bytes of the contents of a blob
@@ -99,7 +99,7 @@ GIT_EXTERN(const void *) git_blob_rawcontent(git_blob *blob);
  * @param blob pointer to the blob
  * @return size on bytes
  */
-GIT_EXTERN(git_off_t) git_blob_rawsize(git_blob *blob);
+GIT_EXTERN(git_off_t) git_blob_rawsize(const git_blob *blob);
 
 /**
  * Read a file from the working folder of a repository
diff --git a/git2/include/git2/branch.h b/git2/include/git2/branch.h
index f55903cd6..3bda43170 100644
--- a/git2/include/git2/branch.h
+++ b/git2/include/git2/branch.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/checkout.h b/git2/include/git2/checkout.h
index c36e2a41b..dfc7e0580 100644
--- a/git2/include/git2/checkout.h
+++ b/git2/include/git2/checkout.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -9,8 +9,7 @@
 
 #include "common.h"
 #include "types.h"
-#include "indexer.h"
-#include "strarray.h"
+#include "diff.h"
 
 /**
  * @file git2/checkout.h
@@ -24,105 +23,113 @@ GIT_BEGIN_DECL
 /**
  * Checkout behavior flags
  *
- * These flags control what checkout does with files.  Pass in a
- * combination of these values OR'ed together.  If you just pass zero
- * (i.e. no flags), then you are effectively doing a "dry run" where no
- * files will be modified.
+ * In libgit2, checkout is used to update the working directory and index
+ * to match a target tree.  Unlike git checkout, it does not move the HEAD
+ * commit for you - use `git_repository_set_head` or the like to do that.
  *
- * Checkout groups the working directory content into 3 classes of files:
- * (1) files that don't need a change, and files that do need a change
- * that either (2) we are allowed to modifed or (3) we are not.  The flags
- * you pass in will decide which files we are allowed to modify.
+ * Checkout looks at (up to) four things: the "target" tree you want to
+ * check out, the "baseline" tree of what was checked out previously, the
+ * working directory for actual files, and the index for staged changes.
  *
- * By default, checkout is not allowed to modify any files.  Anything
- * needing a change would be considered a conflict.
+ * You give checkout one of four strategies for update:
  *
- * GIT_CHECKOUT_UPDATE_UNMODIFIED means that checkout is allowed to update
- * any file where the working directory content matches the HEAD
- * (e.g. either the files match or the file is absent in both places).
+ * - `GIT_CHECKOUT_NONE` is a dry-run strategy that checks for conflicts,
+ *   etc., but doesn't make any actual changes.
  *
- * GIT_CHECKOUT_UPDATE_MISSING means checkout can create a missing file
- * that exists in the index and does not exist in the working directory.
- * This is usually desirable for initial checkout, etc.  Technically, the
- * missing file differs from the HEAD, which is why this is separate.
+ * - `GIT_CHECKOUT_FORCE` is at the opposite extreme, taking any action to
+ *   make the working directory match the target (including potentially
+ *   discarding modified files).
  *
- * GIT_CHECKOUT_UPDATE_MODIFIED means checkout is allowed to update files
- * where the working directory does not match the HEAD so long as the file
- * actually exists in the HEAD.  This option implies UPDATE_UNMODIFIED.
+ * In between those are `GIT_CHECKOUT_SAFE` and `GIT_CHECKOUT_SAFE_CREATE`
+ * both of which only make modifications that will not lose changes.
  *
- * GIT_CHECKOUT_UPDATE_UNTRACKED means checkout is allowed to update files
- * even if there is a working directory version that does not exist in the
- * HEAD (i.e. the file was independently created in the workdir).  This
- * implies UPDATE_UNMODIFIED | UPDATE_MISSING (but *not* UPDATE_MODIFIED).
+ *                      |  target == baseline   |  target != baseline  |
+ * ---------------------|-----------------------|----------------------|
+ *  workdir == baseline |       no action       |  create, update, or  |
+ *                      |                       |     delete file      |
+ * ---------------------|-----------------------|----------------------|
+ *  workdir exists and  |       no action       |   conflict (notify   |
+ *    is != baseline    | notify dirty MODIFIED | and cancel checkout) |
+ * ---------------------|-----------------------|----------------------|
+ *   workdir missing,   | create if SAFE_CREATE |     create file      |
+ *   baseline present   | notify dirty DELETED  |                      |
+ * ---------------------|-----------------------|----------------------|
+ *
+ * The only difference between SAFE and SAFE_CREATE is that SAFE_CREATE
+ * will cause a file to be checked out if it is missing from the working
+ * directory even if it is not modified between the target and baseline.
  *
  *
- * On top of these three basic strategies, there are some modifiers
- * options that can be applied:
+ * To emulate `git checkout`, use `GIT_CHECKOUT_SAFE` with a checkout
+ * notification callback (see below) that displays information about dirty
+ * files.  The default behavior will cancel checkout on conflicts.
  *
- * If any files need update but are disallowed by the strategy, normally
- * checkout calls the conflict callback (if given) and then aborts.
- * GIT_CHECKOUT_ALLOW_CONFLICTS means it is okay to update the files that
- * are allowed by the strategy even if there are conflicts.  The conflict
- * callbacks are still made, but non-conflicting files will be updated.
+ * To emulate `git checkout-index`, use `GIT_CHECKOUT_SAFE_CREATE` with a
+ * notification callback that cancels the operation if a dirty-but-existing
+ * file is found in the working directory.  This core git command isn't
+ * quite "force" but is sensitive about some types of changes.
  *
- * Any unmerged entries in the index are automatically considered conflicts.
- * If you want to proceed anyhow and just skip unmerged entries, you can use
- * GIT_CHECKOUT_SKIP_UNMERGED which is less dangerous than just allowing all
- * conflicts.  Alternatively, use GIT_CHECKOUT_USE_OURS to proceed and
- * checkout the stage 2 ("ours") version.  GIT_CHECKOUT_USE_THEIRS means to
- * proceed and use the stage 3 ("theirs") version.
+ * To emulate `git checkout -f`, use `GIT_CHECKOUT_FORCE`.
  *
- * GIT_CHECKOUT_UPDATE_ONLY means that update is not allowed to create new
- * files or delete old ones, only update existing content.  With this
- * flag, files that needs to be created or deleted are not conflicts -
- * they are just skipped.  This also skips typechanges to existing files
- * (because the old would have to be removed).
- *
- * GIT_CHECKOUT_REMOVE_UNTRACKED means that files in the working directory
- * that are untracked (and not ignored) will be removed altogether.  These
- * untracked files (that do not shadow index entries) are not considered
- * conflicts and would normally be ignored.
+ * To emulate `git clone` use `GIT_CHECKOUT_SAFE_CREATE` in the options.
  *
  *
- * Checkout is "semi-atomic" as in it will go through the work to be done
- * before making any changes and if may decide to abort if there are
- * conflicts, or you can use the conflict callback to explicitly abort the
- * action before any updates are made.  Despite this, if a second process
- * is modifying the filesystem while checkout is running, it can't
- * guarantee that the choices is makes while initially examining the
- * filesystem are still going to be correct as it applies them.
+ * There are some additional flags to modified the behavior of checkout:
+ *
+ * - GIT_CHECKOUT_ALLOW_CONFLICTS makes SAFE mode apply safe file updates
+ *   even if there are conflicts (instead of cancelling the checkout).
+ *
+ * - GIT_CHECKOUT_REMOVE_UNTRACKED means remove untracked files (i.e. not
+ *   in target, baseline, or index, and not ignored) from the working dir.
+ *
+ * - GIT_CHECKOUT_REMOVE_IGNORED means remove ignored files (that are also
+ *   untracked) from the working directory as well.
+ *
+ * - GIT_CHECKOUT_UPDATE_ONLY means to only update the content of files that
+ *   already exist.  Files will not be created nor deleted.  This just skips
+ *   applying adds, deletes, and typechanges.
+ *
+ * - GIT_CHECKOUT_DONT_UPDATE_INDEX prevents checkout from writing the
+ *   updated files' information to the index.
+ *
+ * - Normally, checkout will reload the index and git attributes from disk
+ *   before any operations.  GIT_CHECKOUT_NO_REFRESH prevents this reload.
+ *
+ * - Unmerged index entries are conflicts.  GIT_CHECKOUT_SKIP_UNMERGED skips
+ *   files with unmerged index entries instead.  GIT_CHECKOUT_USE_OURS and
+ *   GIT_CHECKOUT_USE_THEIRS to proceed with the checkout using either the
+ *   stage 2 ("ours") or stage 3 ("theirs") version of files in the index.
  */
 typedef enum {
-	GIT_CHECKOUT_DEFAULT = 0, /** default is a dry run, no actual updates */
+	GIT_CHECKOUT_NONE = 0, /** default is a dry run, no actual updates */
 
-	/** Allow update of entries where working dir matches HEAD. */
-	GIT_CHECKOUT_UPDATE_UNMODIFIED = (1u << 0),
+	/** Allow safe updates that cannot overwrite uncommitted data */
+	GIT_CHECKOUT_SAFE = (1u << 0),
 
-	/** Allow update of entries where working dir does not have file. */
-	GIT_CHECKOUT_UPDATE_MISSING = (1u << 1),
-
-	/** Allow safe updates that cannot overwrite uncommited data */
-	GIT_CHECKOUT_SAFE =
-		(GIT_CHECKOUT_UPDATE_UNMODIFIED | GIT_CHECKOUT_UPDATE_MISSING),
-
-	/** Allow update of entries in working dir that are modified from HEAD. */
-	GIT_CHECKOUT_UPDATE_MODIFIED = (1u << 2),
-
-	/** Update existing untracked files that are now present in the index. */
-	GIT_CHECKOUT_UPDATE_UNTRACKED = (1u << 3),
+	/** Allow safe updates plus creation of missing files */
+	GIT_CHECKOUT_SAFE_CREATE = (1u << 1),
 
 	/** Allow all updates to force working directory to look like index */
-	GIT_CHECKOUT_FORCE =
-		(GIT_CHECKOUT_SAFE | GIT_CHECKOUT_UPDATE_MODIFIED | GIT_CHECKOUT_UPDATE_UNTRACKED),
+	GIT_CHECKOUT_FORCE = (1u << 2),
 
-	/** Allow checkout to make updates even if conflicts are found */
+
+	/** Allow checkout to make safe updates even if conflicts are found */
 	GIT_CHECKOUT_ALLOW_CONFLICTS = (1u << 4),
 
 	/** Remove untracked files not in index (that are not ignored) */
 	GIT_CHECKOUT_REMOVE_UNTRACKED = (1u << 5),
 
+	/** Remove ignored files not in index */
+	GIT_CHECKOUT_REMOVE_IGNORED = (1u << 6),
+
 	/** Only update existing files, don't create new ones */
-	GIT_CHECKOUT_UPDATE_ONLY = (1u << 6),
+	GIT_CHECKOUT_UPDATE_ONLY = (1u << 7),
+
+	/** Normally checkout updates index entries as it goes; this stops that */
+	GIT_CHECKOUT_DONT_UPDATE_INDEX = (1u << 8),
+
+	/** Don't refresh index/config/etc before doing checkout */
+	GIT_CHECKOUT_NO_REFRESH = (1u << 9),
 
 	/**
 	 * THE FOLLOWING OPTIONS ARE NOT YET IMPLEMENTED
@@ -142,56 +149,92 @@ typedef enum {
 
 } git_checkout_strategy_t;
 
+/**
+ * Checkout notification flags
+ *
+ * Checkout will invoke an options notification callback (`notify_cb`) for
+ * certain cases - you pick which ones via `notify_flags`:
+ *
+ * - GIT_CHECKOUT_NOTIFY_CONFLICT invokes checkout on conflicting paths.
+ *
+ * - GIT_CHECKOUT_NOTIFY_DIRTY notifies about "dirty" files, i.e. those that
+ *   do not need an update but no longer match the baseline.  Core git
+ *   displays these files when checkout runs, but won't stop the checkout.
+ *
+ * - GIT_CHECKOUT_NOTIFY_UPDATED sends notification for any file changed.
+ *
+ * - GIT_CHECKOUT_NOTIFY_UNTRACKED notifies about untracked files.
+ *
+ * - GIT_CHECKOUT_NOTIFY_IGNORED notifies about ignored files.
+ *
+ * Returning a non-zero value from this callback will cancel the checkout.
+ * Notification callbacks are made prior to modifying any files on disk.
+ */
+typedef enum {
+	GIT_CHECKOUT_NOTIFY_NONE      = 0,
+	GIT_CHECKOUT_NOTIFY_CONFLICT  = (1u << 0),
+	GIT_CHECKOUT_NOTIFY_DIRTY     = (1u << 1),
+	GIT_CHECKOUT_NOTIFY_UPDATED   = (1u << 2),
+	GIT_CHECKOUT_NOTIFY_UNTRACKED = (1u << 3),
+	GIT_CHECKOUT_NOTIFY_IGNORED   = (1u << 4),
+} git_checkout_notify_t;
+
+/** Checkout notification callback function */
+typedef int (*git_checkout_notify_cb)(
+	git_checkout_notify_t why,
+	const char *path,
+	const git_diff_file *baseline,
+	const git_diff_file *target,
+	const git_diff_file *workdir,
+	void *payload);
+
+/** Checkout progress notification function */
+typedef void (*git_checkout_progress_cb)(
+	const char *path,
+	size_t completed_steps,
+	size_t total_steps,
+	void *payload);
+
 /**
  * Checkout options structure
  *
- * Use zeros to indicate default settings.
- * This needs to be initialized with the `GIT_CHECKOUT_OPTS_INIT` macro:
+ * Zero out for defaults.  Initialize with `GIT_CHECKOUT_OPTS_INIT` macro to
+ * correctly set the `version` field.  E.g.
  *
  *		git_checkout_opts opts = GIT_CHECKOUT_OPTS_INIT;
  */
 typedef struct git_checkout_opts {
 	unsigned int version;
+
 	unsigned int checkout_strategy; /** default will be a dry run */
 
-	int disable_filters; /** don't apply filters like CRLF conversion */
-	int dir_mode;		 /** default is 0755 */
-	int file_mode;		 /** default is 0644 or 0755 as dictated by blob */
-	int file_open_flags; /** default is O_CREAT | O_TRUNC | O_WRONLY */
+	int disable_filters;    /** don't apply filters like CRLF conversion */
+	unsigned int dir_mode;  /** default is 0755 */
+	unsigned int file_mode; /** default is 0644 or 0755 as dictated by blob */
+	int file_open_flags;    /** default is O_CREAT | O_TRUNC | O_WRONLY */
 
-	/** Optional callback made on files where the index differs from the
-	 *  working directory but the rules do not allow update.  Return a
-	 *  non-zero value to abort the checkout.  All such callbacks will be
-	 *  made before any changes are made to the working directory.
-	 */
-	int (*conflict_cb)(
-		const char *conflicting_path,
-		const git_oid *index_oid,
-		unsigned int index_mode,
-		unsigned int wd_mode,
-		void *payload);
-	void *conflict_payload;
+	unsigned int notify_flags; /** see `git_checkout_notify_t` above */
+	git_checkout_notify_cb notify_cb;
+	void *notify_payload;
 
 	/* Optional callback to notify the consumer of checkout progress. */
-	void (*progress_cb)(
-		const char *path,
-		size_t completed_steps,
-		size_t total_steps,
-		void *payload);
+	git_checkout_progress_cb progress_cb;
 	void *progress_payload;
 
 	/** When not zeroed out, array of fnmatch patterns specifying which
 	 *  paths should be taken into account, otherwise all files.
 	 */
 	git_strarray paths;
+
+	git_tree *baseline; /** expected content of workdir, defaults to HEAD */
 } git_checkout_opts;
 
 #define GIT_CHECKOUT_OPTS_VERSION 1
 #define GIT_CHECKOUT_OPTS_INIT {GIT_CHECKOUT_OPTS_VERSION}
 
 /**
- * Updates files in the index and the working tree to match the content of the
- * commit pointed at by HEAD.
+ * Updates files in the index and the working tree to match the content of
+ * the commit pointed at by HEAD.
  *
  * @param repo repository to check out (must be non-bare)
  * @param opts specifies checkout options (may be NULL)
diff --git a/git2/include/git2/clone.h b/git2/include/git2/clone.h
index c6ab8032b..e299c155d 100644
--- a/git2/include/git2/clone.h
+++ b/git2/include/git2/clone.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/commit.h b/git2/include/git2/commit.h
index 872f691ce..764053eaa 100644
--- a/git2/include/git2/commit.h
+++ b/git2/include/git2/commit.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/common.h b/git2/include/git2/common.h
index ad23d2d34..7a4c54c10 100644
--- a/git2/include/git2/common.h
+++ b/git2/include/git2/common.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/config.h b/git2/include/git2/config.h
index b186e70da..19d4cb78d 100644
--- a/git2/include/git2/config.h
+++ b/git2/include/git2/config.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -297,7 +297,7 @@ GIT_EXTERN(int) git_config_get_int32(int32_t *out, const git_config *cfg, const
  *
  * All config files will be looked into, in the order of their
  * defined level. A higher level means a higher priority. The
- * first occurence of the variable will be returned here.
+ * first occurrence of the variable will be returned here.
  *
  * @param out pointer to the variable where the value should be stored
  * @param cfg where to look for the variable
@@ -314,7 +314,7 @@ GIT_EXTERN(int) git_config_get_int64(int64_t *out, const git_config *cfg, const
  *
  * All config files will be looked into, in the order of their
  * defined level. A higher level means a higher priority. The
- * first occurence of the variable will be returned here.
+ * first occurrence of the variable will be returned here.
  *
  * @param out pointer to the variable where the value should be stored
  * @param cfg where to look for the variable
@@ -331,7 +331,7 @@ GIT_EXTERN(int) git_config_get_bool(int *out, const git_config *cfg, const char
  *
  * All config files will be looked into, in the order of their
  * defined level. A higher level means a higher priority. The
- * first occurence of the variable will be returned here.
+ * first occurrence of the variable will be returned here.
  *
  * @param out pointer to the variable's value
  * @param cfg where to look for the variable
diff --git a/git2/include/git2/diff.h b/git2/include/git2/diff.h
index b26dd4214..c052f34f8 100644
--- a/git2/include/git2/diff.h
+++ b/git2/include/git2/diff.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -241,8 +241,8 @@ typedef struct {
  * callback functions and you can use the contents to understand exactly
  * what has changed.
  *
- * The `old_file` repesents the "from" side of the diff and the `new_file`
- * repesents to "to" side of the diff.  What those means depend on the
+ * The `old_file` represents the "from" side of the diff and the `new_file`
+ * represents to "to" side of the diff.  What those means depend on the
  * function that was used to generate the diff and will be documented below.
  * You can also use the `GIT_DIFF_REVERSE` flag to flip it around.
  *
@@ -802,28 +802,50 @@ GIT_EXTERN(int) git_diff_patch_to_str(
  */
 
 /**
- * Directly run a text diff on two blobs.
+ * Directly run a diff on two blobs.
  *
  * Compared to a file, a blob lacks some contextual information. As such,
- * the `git_diff_file` parameters of the callbacks will be filled
- * accordingly to the following: `mode` will be set to 0, `path` will be set
- * to NULL. When dealing with a NULL blob, `oid` will be set to 0.
+ * the `git_diff_file` given to the callback will have some fake data; i.e.
+ * `mode` will be 0 and `path` will be NULL.
  *
- * When at least one of the blobs being dealt with is binary, the
- * `git_diff_delta` binary attribute will be set to 1 and no call to the
- * hunk_cb nor line_cb will be made.
+ * NULL is allowed for either `old_blob` or `new_blob` and will be treated
+ * as an empty blob, with the `oid` set to NULL in the `git_diff_file` data.
+ *
+ * We do run a binary content check on the two blobs and if either of the
+ * blobs looks like binary data, the `git_diff_delta` binary attribute will
+ * be set to 1 and no call to the hunk_cb nor line_cb will be made (unless
+ * you pass `GIT_DIFF_FORCE_TEXT` of course).
  *
  * @return 0 on success, GIT_EUSER on non-zero callback, or error code
  */
 GIT_EXTERN(int) git_diff_blobs(
-	git_blob *old_blob,
-	git_blob *new_blob,
+	const git_blob *old_blob,
+	const git_blob *new_blob,
 	const git_diff_options *options,
 	git_diff_file_cb file_cb,
 	git_diff_hunk_cb hunk_cb,
 	git_diff_data_cb line_cb,
 	void *payload);
 
+/**
+ * Directly run a diff between a blob and a buffer.
+ *
+ * As with `git_diff_blobs`, comparing a blob and buffer lacks some context,
+ * so the `git_diff_file` parameters to the callbacks will be faked a la the
+ * rules for `git_diff_blobs()`.
+ *
+ * @return 0 on success, GIT_EUSER on non-zero callback, or error code
+ */
+GIT_EXTERN(int) git_diff_blob_to_buffer(
+	const git_blob *old_blob,
+	const char *buffer,
+	size_t buffer_len,
+	const git_diff_options *options,
+	git_diff_file_cb file_cb,
+	git_diff_hunk_cb hunk_cb,
+	git_diff_data_cb data_cb,
+	void *payload);
+
 GIT_END_DECL
 
 /** @} */
diff --git a/git2/include/git2/errors.h b/git2/include/git2/errors.h
index 4eb9e94ef..9e0a1a9e6 100644
--- a/git2/include/git2/errors.h
+++ b/git2/include/git2/errors.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/graph.h b/git2/include/git2/graph.h
index c89efa6dd..5850aa6e2 100644
--- a/git2/include/git2/graph.h
+++ b/git2/include/git2/graph.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/ignore.h b/git2/include/git2/ignore.h
index 592c96e65..d0c1877a8 100644
--- a/git2/include/git2/ignore.h
+++ b/git2/include/git2/ignore.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -57,7 +57,7 @@ GIT_EXTERN(int) git_ignore_clear_internal_rules(
  *
  * This function checks the ignore rules to see if they would apply to the
  * given file.  This indicates if the file would be ignored regardless of
- * whether the file is already in the index or commited to the repository.
+ * whether the file is already in the index or committed to the repository.
  *
  * One way to think of this is if you were to do "git add ." on the
  * directory containing the file, would it be added or not?
diff --git a/git2/include/git2/index.h b/git2/include/git2/index.h
index fa9a19785..2df5103fd 100644
--- a/git2/include/git2/index.h
+++ b/git2/include/git2/index.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -312,6 +312,17 @@ GIT_EXTERN(const git_index_entry *) git_index_get_bypath(
  */
 GIT_EXTERN(int) git_index_remove(git_index *index, const char *path, int stage);
 
+/**
+ * Remove all entries from the index under a given directory
+ *
+ * @param index an existing index object
+ * @param dir container directory path
+ * @param stage stage to search
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_index_remove_directory(
+	git_index *index, const char *dir, int stage);
+
 /**
  * Add or update an index entry from an in-memory struct
  *
diff --git a/git2/include/git2/indexer.h b/git2/include/git2/indexer.h
index 41a1503a4..c428d43a8 100644
--- a/git2/include/git2/indexer.h
+++ b/git2/include/git2/indexer.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/merge.h b/git2/include/git2/merge.h
index 59493969c..f4c5d9881 100644
--- a/git2/include/git2/merge.h
+++ b/git2/include/git2/merge.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/message.h b/git2/include/git2/message.h
index e89d022a1..395c88690 100644
--- a/git2/include/git2/message.h
+++ b/git2/include/git2/message.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/net.h b/git2/include/git2/net.h
index 2543ff8e0..6e3525f5d 100644
--- a/git2/include/git2/net.h
+++ b/git2/include/git2/net.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/notes.h b/git2/include/git2/notes.h
index ddd54b039..c51d3732a 100644
--- a/git2/include/git2/notes.h
+++ b/git2/include/git2/notes.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/object.h b/git2/include/git2/object.h
index e5ca17e16..e029f0125 100644
--- a/git2/include/git2/object.h
+++ b/git2/include/git2/object.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/odb.h b/git2/include/git2/odb.h
index 3854fa6f6..f39e7b541 100644
--- a/git2/include/git2/odb.h
+++ b/git2/include/git2/odb.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/odb_backend.h b/git2/include/git2/odb_backend.h
index 7b5a51ed9..029c61b9f 100644
--- a/git2/include/git2/odb_backend.h
+++ b/git2/include/git2/odb_backend.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/oid.h b/git2/include/git2/oid.h
index 43717ad70..6be02da6e 100644
--- a/git2/include/git2/oid.h
+++ b/git2/include/git2/oid.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/pack.h b/git2/include/git2/pack.h
index 585cffef6..bc628c56a 100644
--- a/git2/include/git2/pack.h
+++ b/git2/include/git2/pack.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/push.h b/git2/include/git2/push.h
index 900a1833e..51f059ac4 100644
--- a/git2/include/git2/push.h
+++ b/git2/include/git2/push.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/reflog.h b/git2/include/git2/reflog.h
index 418826d1d..4944530af 100644
--- a/git2/include/git2/reflog.h
+++ b/git2/include/git2/reflog.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/refs.h b/git2/include/git2/refs.h
index cfc96a68c..a0abbc339 100644
--- a/git2/include/git2/refs.h
+++ b/git2/include/git2/refs.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/refspec.h b/git2/include/git2/refspec.h
index 1100e9022..ee06f8eca 100644
--- a/git2/include/git2/refspec.h
+++ b/git2/include/git2/refspec.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -56,7 +56,7 @@ GIT_EXTERN(int) git_refspec_src_matches(const git_refspec *refspec, const char *
  * Transform a reference to its target following the refspec's rules
  *
  * @param out where to store the target name
- * @param outlen the size ouf the `out` buffer
+ * @param outlen the size of the `out` buffer
  * @param spec the refspec
  * @param name the name of the reference to transform
  * @return 0, GIT_EBUFS or another error
diff --git a/git2/include/git2/remote.h b/git2/include/git2/remote.h
index 5f6a78097..a0f5d5246 100644
--- a/git2/include/git2/remote.h
+++ b/git2/include/git2/remote.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/repository.h b/git2/include/git2/repository.h
index 1371d5409..e207e5bb5 100644
--- a/git2/include/git2/repository.h
+++ b/git2/include/git2/repository.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -609,7 +609,7 @@ GIT_EXTERN(int) git_repository_set_head_detached(
  * updated into making it point to the peeled Commit, and 0 is returned.
  *
  * If the HEAD is already detached and points to a non commitish, the HEAD is 
- * unaletered, and -1 is returned.
+ * unaltered, and -1 is returned.
  *
  * Otherwise, the HEAD will be detached and point to the peeled Commit.
  *
diff --git a/git2/include/git2/reset.h b/git2/include/git2/reset.h
index b5fc4a6cb..00d25dff0 100644
--- a/git2/include/git2/reset.h
+++ b/git2/include/git2/reset.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/revparse.h b/git2/include/git2/revparse.h
index 3df6fef7f..6edb7767c 100644
--- a/git2/include/git2/revparse.h
+++ b/git2/include/git2/revparse.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/revwalk.h b/git2/include/git2/revwalk.h
index 893ad2c9d..ad57b622e 100644
--- a/git2/include/git2/revwalk.h
+++ b/git2/include/git2/revwalk.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/signature.h b/git2/include/git2/signature.h
index 7a265bd8e..00d19de66 100644
--- a/git2/include/git2/signature.h
+++ b/git2/include/git2/signature.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/stash.h b/git2/include/git2/stash.h
index b57d47b3a..cf8bc9d4c 100644
--- a/git2/include/git2/stash.h
+++ b/git2/include/git2/stash.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/status.h b/git2/include/git2/status.h
index a898d1f34..d0c4a496d 100644
--- a/git2/include/git2/status.h
+++ b/git2/include/git2/status.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -210,7 +210,7 @@ GIT_EXTERN(int) git_status_file(
  *
  * This function checks the ignore rules to see if they would apply to the
  * given file.  This indicates if the file would be ignored regardless of
- * whether the file is already in the index or commited to the repository.
+ * whether the file is already in the index or committed to the repository.
  *
  * One way to think of this is if you were to do "git add ." on the
  * directory containing the file, would it be added or not?
diff --git a/git2/include/git2/strarray.h b/git2/include/git2/strarray.h
index 338d13873..6ea570c14 100644
--- a/git2/include/git2/strarray.h
+++ b/git2/include/git2/strarray.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/submodule.h b/git2/include/git2/submodule.h
index 90e45cebd..1abd33e79 100644
--- a/git2/include/git2/submodule.h
+++ b/git2/include/git2/submodule.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
@@ -504,6 +504,24 @@ GIT_EXTERN(int) git_submodule_status(
 	unsigned int *status,
 	git_submodule *submodule);
 
+/**
+ * Get the locations of submodule information.
+ *
+ * This is a bit like a very lightweight version of `git_submodule_status`.
+ * It just returns a made of the first four submodule status values (i.e.
+ * the ones like GIT_SUBMODULE_STATUS_IN_HEAD, etc) that tell you where the
+ * submodule data comes from (i.e. the HEAD commit, gitmodules file, etc.).
+ * This can be useful if you want to know if the submodule is present in the
+ * working directory at this point in time, etc.
+ *
+ * @param status Combination of first four `GIT_SUBMODULE_STATUS` flags
+ * @param submodule Submodule for which to get status
+ * @return 0 on success, <0 on error
+ */
+GIT_EXTERN(int) git_submodule_location(
+	unsigned int *location_status,
+	git_submodule *submodule);
+
 /** @} */
 GIT_END_DECL
 #endif
diff --git a/git2/include/git2/tag.h b/git2/include/git2/tag.h
index a9773be56..1ffeb0b4a 100644
--- a/git2/include/git2/tag.h
+++ b/git2/include/git2/tag.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/threads.h b/git2/include/git2/threads.h
index f448f6a4d..11f89729a 100644
--- a/git2/include/git2/threads.h
+++ b/git2/include/git2/threads.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/transport.h b/git2/include/git2/transport.h
index c2f205295..fba5fb920 100644
--- a/git2/include/git2/transport.h
+++ b/git2/include/git2/transport.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/tree.h b/git2/include/git2/tree.h
index b3c22e71d..7726a6599 100644
--- a/git2/include/git2/tree.h
+++ b/git2/include/git2/tree.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/types.h b/git2/include/git2/types.h
index 06fcf3613..c16bb8872 100644
--- a/git2/include/git2/types.h
+++ b/git2/include/git2/types.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/git2/include/git2/version.h b/git2/include/git2/version.h
index 8edbe323c..bc03e85d6 100644
--- a/git2/include/git2/version.h
+++ b/git2/include/git2/version.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 the libgit2 contributors
+ * Copyright (C) the libgit2 contributors. All rights reserved.
  *
  * This file is part of libgit2, distributed under the GNU GPL v2 with
  * a Linking Exception. For full terms see the included COPYING file.
diff --git a/native/v8_extensions/git.mm b/native/v8_extensions/git.mm
index 8a334ed02..dae65d953 100644
--- a/native/v8_extensions/git.mm
+++ b/native/v8_extensions/git.mm
@@ -86,7 +86,7 @@ public:
     char *copiedPath = (char *)malloc(sizeof(char) * (strlen(path) + 1));
     strcpy(copiedPath, path);
     git_checkout_opts options = GIT_CHECKOUT_OPTS_INIT;
-    options.checkout_strategy = GIT_CHECKOUT_UPDATE_MODIFIED;
+    options.checkout_strategy = GIT_CHECKOUT_FORCE;
     git_strarray paths;
     paths.count = 1;
     paths.strings = &copiedPath;