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diff --git a/include/git2/pack.h b/include/git2/pack.h
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+/*
+ * 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.
+ */
+#ifndef INCLUDE_git_pack_h__
+#define INCLUDE_git_pack_h__
+
+#include "common.h"
+#include "oid.h"
+#include "indexer.h"
+
+/**
+ * @file git2/pack.h
+ * @brief Git pack management routines
+ *
+ * Packing objects
+ * ---------------
+ *
+ * Creation of packfiles requires two steps:
+ *
+ * - First, insert all the objects you want to put into the packfile
+ *   using `git_packbuilder_insert` and `git_packbuilder_insert_tree`.
+ *   It's important to add the objects in recency order ("in the order
+ *   that they are 'reachable' from head").
+ *
+ *   "ANY order will give you a working pack, ... [but it is] the thing
+ *   that gives packs good locality. It keeps the objects close to the
+ *   head (whether they are old or new, but they are _reachable_ from the
+ *   head) at the head of the pack. So packs actually have absolutely
+ *   _wonderful_ IO patterns." - Linus Torvalds
+ *   git.git/Documentation/technical/pack-heuristics.txt
+ *
+ * - Second, use `git_packbuilder_write` or `git_packbuilder_foreach` to
+ *   write the resulting packfile.
+ *
+ *   libgit2 will take care of the delta ordering and generation.
+ *   `git_packbuilder_set_threads` can be used to adjust the number of
+ *   threads used for the process.
+ *
+ * See tests/pack/packbuilder.c for an example.
+ *
+ * @ingroup Git
+ * @{
+ */
+GIT_BEGIN_DECL
+
+/**
+ * Stages that are reported by the packbuilder progress callback.
+ */
+typedef enum {
+	GIT_PACKBUILDER_ADDING_OBJECTS = 0,
+	GIT_PACKBUILDER_DELTAFICATION = 1
+} git_packbuilder_stage_t;
+
+/**
+ * Initialize a new packbuilder
+ *
+ * @param out The new packbuilder object
+ * @param repo The repository
+ *
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_new(git_packbuilder **out, git_repository *repo);
+
+/**
+ * Set number of threads to spawn
+ *
+ * By default, libgit2 won't spawn any threads at all;
+ * when set to 0, libgit2 will autodetect the number of
+ * CPUs.
+ *
+ * @param pb The packbuilder
+ * @param n Number of threads to spawn
+ * @return number of actual threads to be used
+ */
+GIT_EXTERN(unsigned int) git_packbuilder_set_threads(git_packbuilder *pb, unsigned int n);
+
+/**
+ * Insert a single object
+ *
+ * For an optimal pack it's mandatory to insert objects in recency order,
+ * commits followed by trees and blobs.
+ *
+ * @param pb The packbuilder
+ * @param id The oid of the commit
+ * @param name The name; might be NULL
+ *
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_insert(git_packbuilder *pb, const git_oid *id, const char *name);
+
+/**
+ * Insert a root tree object
+ *
+ * This will add the tree as well as all referenced trees and blobs.
+ *
+ * @param pb The packbuilder
+ * @param id The oid of the root tree
+ *
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_insert_tree(git_packbuilder *pb, const git_oid *id);
+
+/**
+ * Insert a commit object
+ *
+ * This will add a commit as well as the completed referenced tree.
+ *
+ * @param pb The packbuilder
+ * @param id The oid of the commit
+ *
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_insert_commit(git_packbuilder *pb, const git_oid *id);
+
+/**
+ * Insert objects as given by the walk
+ *
+ * Those commits and all objects they reference will be inserted into
+ * the packbuilder.
+ *
+ * @param pb the packbuilder
+ * @param walk the revwalk to use to fill the packbuilder
+ *
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_insert_walk(git_packbuilder *pb, git_revwalk *walk);
+
+/**
+ * Recursively insert an object and its referenced objects
+ *
+ * Insert the object as well as any object it references.
+ *
+ * @param pb the packbuilder
+ * @param id the id of the root object to insert
+ * @param name optional name for the object
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_insert_recur(git_packbuilder *pb, const git_oid *id, const char *name);
+
+/**
+ * Write the contents of the packfile to an in-memory buffer
+ *
+ * The contents of the buffer will become a valid packfile, even though there
+ * will be no attached index
+ *
+ * @param buf Buffer where to write the packfile
+ * @param pb The packbuilder
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_write_buf(git_buf *buf, git_packbuilder *pb);
+
+/**
+ * Write the new pack and corresponding index file to path.
+ *
+ * @param pb The packbuilder
+ * @param path Path to the directory where the packfile and index should be stored, or NULL for default location
+ * @param mode permissions to use creating a packfile or 0 for defaults
+ * @param progress_cb function to call with progress information from the indexer (optional)
+ * @param progress_cb_payload payload for the progress callback (optional)
+ *
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_write(
+	git_packbuilder *pb,
+	const char *path,
+	unsigned int mode,
+	git_indexer_progress_cb progress_cb,
+	void *progress_cb_payload);
+
+#ifndef GIT_DEPRECATE_HARD
+/**
+ * Get the packfile's hash
+ *
+ * A packfile's name is derived from the sorted hashing of all object
+ * names. This is only correct after the packfile has been written.
+ *
+ * @deprecated use git_packbuilder_name
+ * @param pb The packbuilder object
+ * @return 0 or an error code
+ */
+GIT_EXTERN(const git_oid *) git_packbuilder_hash(git_packbuilder *pb);
+#endif
+
+/**
+ * Get the unique name for the resulting packfile.
+ *
+ * The packfile's name is derived from the packfile's content.
+ * This is only correct after the packfile has been written.
+ *
+ * @param pb the packbuilder instance
+ * @return a NUL terminated string for the packfile name
+ */
+GIT_EXTERN(const char *) git_packbuilder_name(git_packbuilder *pb);
+
+/**
+ * Callback used to iterate over packed objects
+ *
+ * @see git_packbuilder_foreach
+ *
+ * @param buf A pointer to the object's data
+ * @param size The size of the underlying object
+ * @param payload Payload passed to git_packbuilder_foreach
+ * @return non-zero to terminate the iteration
+ */
+typedef int GIT_CALLBACK(git_packbuilder_foreach_cb)(void *buf, size_t size, void *payload);
+
+/**
+ * Create the new pack and pass each object to the callback
+ *
+ * @param pb the packbuilder
+ * @param cb the callback to call with each packed object's buffer
+ * @param payload the callback's data
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_foreach(git_packbuilder *pb, git_packbuilder_foreach_cb cb, void *payload);
+
+/**
+ * Get the total number of objects the packbuilder will write out
+ *
+ * @param pb the packbuilder
+ * @return the number of objects in the packfile
+ */
+GIT_EXTERN(size_t) git_packbuilder_object_count(git_packbuilder *pb);
+
+/**
+ * Get the number of objects the packbuilder has already written out
+ *
+ * @param pb the packbuilder
+ * @return the number of objects which have already been written
+ */
+GIT_EXTERN(size_t) git_packbuilder_written(git_packbuilder *pb);
+
+/** Packbuilder progress notification function */
+typedef int GIT_CALLBACK(git_packbuilder_progress)(
+	int stage,
+	uint32_t current,
+	uint32_t total,
+	void *payload);
+
+/**
+ * Set the callbacks for a packbuilder
+ *
+ * @param pb The packbuilder object
+ * @param progress_cb Function to call with progress information during
+ * pack building. Be aware that this is called inline with pack building
+ * operations, so performance may be affected.
+ * @param progress_cb_payload Payload for progress callback.
+ * @return 0 or an error code
+ */
+GIT_EXTERN(int) git_packbuilder_set_callbacks(
+	git_packbuilder *pb,
+	git_packbuilder_progress progress_cb,
+	void *progress_cb_payload);
+
+/**
+ * Free the packbuilder and all associated data
+ *
+ * @param pb The packbuilder
+ */
+GIT_EXTERN(void) git_packbuilder_free(git_packbuilder *pb);
+
+/** @} */
+GIT_END_DECL
+#endif