/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
#if !defined(ORG_FOSSIL_SCM_FSL_VPATH_H_INCLUDED)
#define ORG_FOSSIL_SCM_FSL_VPATH_H_INCLUDED
/*
Copyright 2013-2021 The Libfossil Authors, see LICENSES/BSD-2-Clause.txt
SPDX-License-Identifier: BSD-2-Clause-FreeBSD
SPDX-FileCopyrightText: 2021 The Libfossil Authors
SPDX-ArtifactOfProjectName: Libfossil
SPDX-FileType: Code
Heavily indebted to the Fossil SCM project (https://fossil-scm.org).
*****************************************************************************
This file declares public APIs relating to calculating paths via
Fossil SCM version history.
*/
#include "fossil-internal.h" /* MUST come first b/c of config macros */
#if defined(__cplusplus)
extern "C" {
#endif
typedef struct fsl_vpath_node fsl_vpath_node;
typedef struct fsl_vpath fsl_vpath;
/**
Holds information for a single node in a path of checkin versions.
@see fsl_vpath
*/
struct fsl_vpath_node {
/** ID for this node */
fsl_id_t rid;
/** True if pFrom is the parent of rid */
char fromIsParent;
/** True if primary side of common ancestor */
char isPrimary;
/* HISTORICAL: Abbreviate output in "fossil bisect ls" */
char isHidden;
/** Node this one came from. */
fsl_vpath_node *pFrom;
union {
/** List of nodes of the same generation */
fsl_vpath_node *pPeer;
/** Next on path from beginning to end */
fsl_vpath_node *pTo;
} u;
/** List of all nodes */
fsl_vpath_node *pAll;
};
/**
A utility type for collecting "paths" between two checkin versions.
*/
struct fsl_vpath{
/** Current generation of nodes */
fsl_vpath_node *pCurrent;
/** All nodes */
fsl_vpath_node *pAll;
/** Nodes seen before */
fsl_id_bag seen;
/** Number of steps from first to last. */
int nStep;
/** Earliest node in the path. */
fsl_vpath_node *pStart;
/** Common ancestor of pStart and pEnd */
fsl_vpath_node *pPivot;
/** Most recent node in the path. */
fsl_vpath_node *pEnd;
};
/**
An empty-initialize fsl_vpath object, intended for const-copy
initialization.
*/
#define fsl_vpath_empty_m {0,0,fsl_id_bag_empty_m,0,0,0,0}
/**
An empty-initialize fsl_vpath object, intended for copy
initialization.
*/
FSL_EXPORT const fsl_vpath fsl_vpath_empty;
/**
Returns the first node in p's path.
The returned node is owned by path may be invalidated by any APIs
which manipulate path.
*/
FSL_EXPORT fsl_vpath_node * fsl_vpath_first(fsl_vpath *p);
/**
Returns the last node in p's path.
The returned node is owned by path may be invalidated by any APIs
which manipulate path.
*/
FSL_EXPORT fsl_vpath_node * fsl_vpath_last(fsl_vpath *p);
/**
Returns the next node p's path.
The returned node is owned by path may be invalidated by any APIs
which manipulate path.
Intended to be used like this:
@code
for( p = fsl_vpath_first(path) ;
p ;
p = fsl_vpath_next(p)){
...
}
@endcode
*/
FSL_EXPORT fsl_vpath_node * fsl_vpath_next(fsl_vpath_node *p);
/**
Returns p's path length.
*/
FSL_EXPORT int fsl_vpath_length(fsl_vpath const * p);
/**
Frees all nodes in path (which must not be NULL) and resets all
state in path. Does not free path.
*/
FSL_EXPORT void fsl_vpath_clear(fsl_vpath *path);
/**
Find the mid-point of the path. If the path contains fewer than
2 steps, returns 0. The returned node is owned by path may be
invalidated by any APIs which manipulate path.
*/
FSL_EXPORT fsl_vpath_node * fsl_vpath_midpoint(fsl_vpath * path);
/**
Computes the shortest path from checkin versions iFrom to iTo
(inclusive), storing the result state in path. If path has
state before this is called, it is cleared by this call.
iFrom and iTo must both be valid checkin version RIDs.
If directOnly is true, then use only the "primary" links from
parent to child. In other words, ignore merges.
On success, returns 0 and path->pStart will point to the
beginning of the path (the iFrom node). If pStart is 0 then no
path could be found but 0 is still returned.
Elements of the path can be traversed like so:
@code
fsl_vpath path = fsl_vpath_empty;
fsl_vpath_node * n = 0;
int rc = fsl_vpath_shortest(f, &path, versionFrom, versionTo, 1, 0);
if(rc) { ... error ... }
for( n = fsl_vpath_first(&path); n; n = fsl_vpath_next(n) ){
...
}
fsl_vpath_clear(&path);
@endcode
On error, f's error state may be updated with a description of the
problem.
*/
FSL_EXPORT int fsl_vpath_shortest( fsl_cx * f, fsl_vpath * path,
fsl_id_t iFrom, fsl_id_t iTo,
char directOnly, char oneWayOnly );
#if defined(__cplusplus)
} /*extern "C"*/
#endif
#endif
/* ORG_FOSSIL_SCM_FSL_VPATH_H_INCLUDED */