/*

 * 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_revwalk_h__

#define INCLUDE_git_revwalk_h__

#include "common.h"

#include "types.h"

#include "oid.h"

/**

 * @file git2/revwalk.h

 * @brief Git revision traversal routines

 * @defgroup git_revwalk Git revision traversal routines

 * @ingroup Git

 * @{

 */

GIT_BEGIN_DECL

/**

 * Flags to specify the sorting which a revwalk should perform.

 */

typedef enum {

	/**

	 * Sort the output with the same default time-order method from git.

	 * This is the default sorting for new walkers.

	 */

	GIT_SORT_NONE = 0,

	/**

	 * Sort the repository contents in topological order (parents before

	 * children); this sorting mode can be combined with time sorting to

	 * produce git's "time-order".

	 */

	GIT_SORT_TOPOLOGICAL = 1 << 0,

	/**

	 * Sort the repository contents by commit time;

	 * this sorting mode can be combined with

	 * topological sorting.

	 */

	GIT_SORT_TIME = 1 << 1,

	/**

	 * Iterate through the repository contents in reverse

	 * order; this sorting mode can be combined with

	 * any of the above.

	 */

	GIT_SORT_REVERSE = 1 << 2,

} git_sort_t;

/**

 * Allocate a new revision walker to iterate through a repo.

 *

 * This revision walker uses a custom memory pool and an internal

 * commit cache, so it is relatively expensive to allocate.

 *

 * For maximum performance, this revision walker should be

 * reused for different walks.

 *

 * This revision walker is *not* thread safe: it may only be

 * used to walk a repository on a single thread; however,

 * it is possible to have several revision walkers in

 * several different threads walking the same repository.

 *

 * @param out pointer to the new revision walker

 * @param repo the repo to walk through

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_new(git_revwalk **out, git_repository *repo);

/**

 * Reset the revision walker for reuse.

 *

 * This will clear all the pushed and hidden commits, and

 * leave the walker in a blank state (just like at

 * creation) ready to receive new commit pushes and

 * start a new walk.

 *

 * The revision walk is automatically reset when a walk

 * is over.

 *

 * @param walker handle to reset.

 */

GIT_EXTERN(void) git_revwalk_reset(git_revwalk *walker);

/**

 * Add a new root for the traversal

 *

 * The pushed commit will be marked as one of the roots from which to

 * start the walk. This commit may not be walked if it or a child is

 * hidden.

 *

 * At least one commit must be pushed onto the walker before a walk

 * can be started.

 *

 * The given id must belong to a committish on the walked

 * repository.

 *

 * @param walk the walker being used for the traversal.

 * @param id the oid of the commit to start from.

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_push(git_revwalk *walk, const git_oid *id);

/**

 * Push matching references

 *

 * The OIDs pointed to by the references that match the given glob

 * pattern will be pushed to the revision walker.

 *

 * A leading 'refs/' is implied if not present as well as a trailing

 * '/\*' if the glob lacks '?', '\*' or '['.

 *

 * Any references matching this glob which do not point to a

 * committish will be ignored.

 *

 * @param walk the walker being used for the traversal

 * @param glob the glob pattern references should match

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_push_glob(git_revwalk *walk, const char *glob);

/**

 * Push the repository's HEAD

 *

 * @param walk the walker being used for the traversal

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_push_head(git_revwalk *walk);

/**

 * Mark a commit (and its ancestors) uninteresting for the output.

 *

 * The given id must belong to a committish on the walked

 * repository.

 *

 * The resolved commit and all its parents will be hidden from the

 * output on the revision walk.

 *

 * @param walk the walker being used for the traversal.

 * @param commit_id the oid of commit that will be ignored during the traversal

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_hide(git_revwalk *walk, const git_oid *commit_id);

/**

 * Hide matching references.

 *

 * The OIDs pointed to by the references that match the given glob

 * pattern and their ancestors will be hidden from the output on the

 * revision walk.

 *

 * A leading 'refs/' is implied if not present as well as a trailing

 * '/\*' if the glob lacks '?', '\*' or '['.

 *

 * Any references matching this glob which do not point to a

 * committish will be ignored.

 *

 * @param walk the walker being used for the traversal

 * @param glob the glob pattern references should match

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_hide_glob(git_revwalk *walk, const char *glob);

/**

 * Hide the repository's HEAD

 *

 * @param walk the walker being used for the traversal

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_hide_head(git_revwalk *walk);

/**

 * Push the OID pointed to by a reference

 *

 * The reference must point to a committish.

 *

 * @param walk the walker being used for the traversal

 * @param refname the reference to push

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_push_ref(git_revwalk *walk, const char *refname);

/**

 * Hide the OID pointed to by a reference

 *

 * The reference must point to a committish.

 *

 * @param walk the walker being used for the traversal

 * @param refname the reference to hide

 * @return 0 or an error code

 */

GIT_EXTERN(int) git_revwalk_hide_ref(git_revwalk *walk, const char *refname);

/**

 * Get the next commit from the revision walk.

 *

 * The initial call to this method is *not* blocking when

 * iterating through a repo with a time-sorting mode.

 *

 * Iterating with Topological or inverted modes makes the initial

 * call blocking to preprocess the commit list, but this block should be

 * mostly unnoticeable on most repositories (topological preprocessing

 * times at 0.3s on the git.git repo).

 *

 * The revision walker is reset when the walk is over.

 *

 * @param out Pointer where to store the oid of the next commit

 * @param walk the walker to pop the commit from.

 * @return 0 if the next commit was found;

 *	GIT_ITEROVER if there are no commits left to iterate

 */

GIT_EXTERN(int) git_revwalk_next(git_oid *out, git_revwalk *walk);

/**

 * Change the sorting mode when iterating through the

 * repository's contents.

 *

 * Changing the sorting mode resets the walker.

 *

 * @param walk the walker being used for the traversal.

 * @param sort_mode combination of GIT_SORT_XXX flags

 */

GIT_EXTERN(void) git_revwalk_sorting(git_revwalk *walk, unsigned int sort_mode);

/**

 * Push and hide the respective endpoints of the given range.

 *

 * The range should be of the form

 *   <commit>..<commit>

 * where each <commit> is in the form accepted by 'git_revparse_single'.

 * The left-hand commit will be hidden and the right-hand commit pushed.

 *

 * @param walk the walker being used for the traversal

 * @param range the range

 * @return 0 or an error code

 *

 */

GIT_EXTERN(int) git_revwalk_push_range(git_revwalk *walk, const char *range);

/**

 * Simplify the history by first-parent

 *

 * No parents other than the first for each commit will be enqueued.

 */

GIT_EXTERN(void) git_revwalk_simplify_first_parent(git_revwalk *walk);

/**

 * Free a revision walker previously allocated.

 *

 * @param walk traversal handle to close. If NULL nothing occurs.

 */

GIT_EXTERN(void) git_revwalk_free(git_revwalk *walk);

/**

 * Return the repository on which this walker

 * is operating.

 *

 * @param walk the revision walker

 * @return the repository being walked

 */

GIT_EXTERN(git_repository *) git_revwalk_repository(git_revwalk *walk);

/**

 * This is a callback function that user can provide to hide a

 * commit and its parents. If the callback function returns non-zero value,

 * then this commit and its parents will be hidden.

 *

 * @param commit_id oid of Commit

 * @param payload User-specified pointer to data to be passed as data payload

 */

typedef int(*git_revwalk_hide_cb)(

	const git_oid *commit_id,

	void *payload);

/**

 * Adds a callback function to hide a commit and its parents

 *

 * @param walk the revision walker

 * @param hide_cb  callback function to hide a commit and its parents

 * @param payload  data payload to be passed to callback function

 */

GIT_EXTERN(int) git_revwalk_add_hide_cb(

	git_revwalk *walk,

	git_revwalk_hide_cb hide_cb,

	void *payload);

/** @} */

GIT_END_DECL

#endif