Proxy.cs

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using LibGit2Sharp.Core.Handles;
using LibGit2Sharp.Handlers;

// ReSharper disable InconsistentNaming
namespace LibGit2Sharp.Core
{
    internal class Proxy
    {
        #region giterr_

        public static void giterr_set_str(GitErrorCategory error_class, Exception exception)
        {
            if (exception is OutOfMemoryException)
            {
                NativeMethods.giterr_set_oom();
            }
            else
            {
                NativeMethods.giterr_set_str(error_class, ErrorMessageFromException(exception));
            }
        }

        public static void giterr_set_str(GitErrorCategory error_class, String errorString)
        {
            NativeMethods.giterr_set_str(error_class, errorString);
        }

        /// <summary>
        /// This method will take an exception and try to generate an error message
        /// that captures the important messages of the error.
        /// The formatting is a bit subjective.
        /// </summary>
        /// <param name="ex"></param>
        /// <returns></returns>
        public static string ErrorMessageFromException(Exception ex)
        {
            StringBuilder sb = new StringBuilder();
            BuildErrorMessageFromException(sb, 0, ex);
            return sb.ToString();
        }

        private static void BuildErrorMessageFromException(StringBuilder sb, int level, Exception ex)
        {
            string indent = new string(' ', level * 4);
            sb.AppendFormat("{0}{1}", indent, ex.Message);

            if (ex is AggregateException)
            {
                AggregateException aggregateException = ((AggregateException)ex).Flatten();

                if (aggregateException.InnerExceptions.Count == 1)
                {
                    sb.AppendLine();
                    sb.AppendLine();

                    sb.AppendFormat("{0}Contained Exception:{1}", indent, Environment.NewLine);
                    BuildErrorMessageFromException(sb, level + 1, aggregateException.InnerException);
                }
                else
                {
                    sb.AppendLine();
                    sb.AppendLine();

                    sb.AppendFormat("{0}Contained Exceptions:{1}", indent, Environment.NewLine);
                    for (int i = 0; i < aggregateException.InnerExceptions.Count; i++)
                    {
                        if (i != 0)
                        {
                            sb.AppendLine();
                            sb.AppendLine();
                        }

                        BuildErrorMessageFromException(sb, level + 1, aggregateException.InnerExceptions[i]);
                    }
                }
            }
            else if (ex.InnerException != null)
            {
                sb.AppendLine();
                sb.AppendLine();
                sb.AppendFormat("{0}Inner Exception:{1}", indent, Environment.NewLine);
                BuildErrorMessageFromException(sb, level + 1, ex.InnerException);
            }
        }

        #endregion

        #region git_blame_

        public static BlameSafeHandle git_blame_file(
            RepositorySafeHandle repo,
            FilePath path,
            GitBlameOptions options)
        {
            BlameSafeHandle handle;
            int res = NativeMethods.git_blame_file(out handle, repo, path, options);
            Ensure.ZeroResult(res);
            return handle;
        }

        public static GitBlameHunk git_blame_get_hunk_byindex(BlameSafeHandle blame, uint idx)
        {
            return NativeMethods.git_blame_get_hunk_byindex(blame, idx).MarshalAs<GitBlameHunk>(false);
        }

        public static void git_blame_free(IntPtr blame)
        {
            NativeMethods.git_blame_free(blame);
        }

        #endregion

        #region git_blob_

        public static ObjectId git_blob_create_fromchunks(RepositorySafeHandle repo, FilePath hintpath, NativeMethods.source_callback fileCallback)
        {
            var oid = new GitOid();
            int res = NativeMethods.git_blob_create_fromchunks(ref oid, repo, hintpath, fileCallback, IntPtr.Zero);

            if (res == (int)GitErrorCode.User)
            {
                throw new EndOfStreamException("The stream ended unexpectedly");
            }

            Ensure.ZeroResult(res);

            return oid;
        }

        public static ObjectId git_blob_create_fromdisk(RepositorySafeHandle repo, FilePath path)
        {
            var oid = new GitOid();
            int res = NativeMethods.git_blob_create_fromdisk(ref oid, repo, path);
            Ensure.ZeroResult(res);

            return oid;
        }

        public static ObjectId git_blob_create_fromfile(RepositorySafeHandle repo, FilePath path)
        {
            var oid = new GitOid();
            int res = NativeMethods.git_blob_create_fromworkdir(ref oid, repo, path);
            Ensure.ZeroResult(res);

            return oid;
        }

        public static UnmanagedMemoryStream git_blob_filtered_content_stream(RepositorySafeHandle repo, ObjectId id, FilePath path, bool check_for_binary_data)
        {
            var buf = new GitBuf();
            var handle = new ObjectSafeWrapper(id, repo).ObjectPtr;

            return new RawContentStream(handle, h =>
            {
                Ensure.ZeroResult(NativeMethods.git_blob_filtered_content(buf, h, path, check_for_binary_data));
                return buf.ptr;
            },
            h => (long)buf.size,
            new[] { buf });
        }

        public static UnmanagedMemoryStream git_blob_rawcontent_stream(RepositorySafeHandle repo, ObjectId id, Int64 size)
        {
            var handle = new ObjectSafeWrapper(id, repo).ObjectPtr;
            return new RawContentStream(handle, NativeMethods.git_blob_rawcontent, h => size);
        }

        public static long git_blob_rawsize(GitObjectSafeHandle obj)
        {
            return NativeMethods.git_blob_rawsize(obj);
        }

        public static bool git_blob_is_binary(GitObjectSafeHandle obj)
        {
            int res = NativeMethods.git_blob_is_binary(obj);
            Ensure.BooleanResult(res);

            return (res == 1);
        }

        #endregion

        #region git_branch_

        public static ReferenceSafeHandle git_branch_create_from_annotated(RepositorySafeHandle repo, string branch_name, string targetIdentifier, bool force)
        {
            ReferenceSafeHandle reference;

            using (var annotatedCommit = git_annotated_commit_from_revspec(repo, targetIdentifier))
            {
                int res = NativeMethods.git_branch_create_from_annotated(out reference, repo, branch_name, annotatedCommit, force);
                Ensure.ZeroResult(res);
            }

            return reference;
        }

        public static void git_branch_delete(ReferenceSafeHandle reference)
        {
            int res = NativeMethods.git_branch_delete(reference);
            Ensure.ZeroResult(res);
        }

        public static IEnumerable<Branch> git_branch_iterator(Repository repo, GitBranchType branchType)
        {
            return git_iterator((out BranchIteratorSafeHandle iter_out) =>
                                    NativeMethods.git_branch_iterator_new(out iter_out, repo.Handle, branchType),
                                (BranchIteratorSafeHandle iter, out ReferenceSafeHandle ref_out, out int res) =>
                                    {
                                        GitBranchType type_out;
                                        res = NativeMethods.git_branch_next(out ref_out, out type_out, iter);
                                        return new { BranchType = type_out };
                                    },
                                (handle, payload) =>
                                    {
                                        var reference = Reference.BuildFromPtr<Reference>(handle, repo);
                                        return new Branch(repo, reference, reference.CanonicalName);
                                    });
        }

        public static void git_branch_iterator_free(IntPtr iter)
        {
            NativeMethods.git_branch_iterator_free(iter);
        }

        public static ReferenceSafeHandle git_branch_move(ReferenceSafeHandle reference, string new_branch_name, bool force)
        {
            ReferenceSafeHandle ref_out;
            int res = NativeMethods.git_branch_move(out ref_out, reference, new_branch_name, force);
            Ensure.ZeroResult(res);
            return ref_out;
        }

        public static string git_branch_remote_name(RepositorySafeHandle repo, string canonical_branch_name, bool shouldThrowIfNotFound)
        {
            using (var buf = new GitBuf())
            {
                int res = NativeMethods.git_branch_remote_name(buf, repo, canonical_branch_name);

                if (!shouldThrowIfNotFound &&
                    (res == (int)GitErrorCode.NotFound || res == (int)GitErrorCode.Ambiguous))
                {
                    return null;
                }

                Ensure.ZeroResult(res);
                return LaxUtf8Marshaler.FromNative(buf.ptr);
            }
        }

        public static string git_branch_upstream_name(RepositorySafeHandle handle, string canonicalReferenceName)
        {
            using (var buf = new GitBuf())
            {
                int res = NativeMethods.git_branch_upstream_name(buf, handle, canonicalReferenceName);
                if (res == (int)GitErrorCode.NotFound)
                {
                    return null;
                }

                Ensure.ZeroResult(res);
                return LaxUtf8Marshaler.FromNative(buf.ptr);
            }
        }

        #endregion

        #region git_buf_

        public static void git_buf_free(GitBuf buf)
        {
            NativeMethods.git_buf_free(buf);
        }

        #endregion

        #region git_checkout_

        public static void git_checkout_tree(
            RepositorySafeHandle repo,
            ObjectId treeId,
            ref GitCheckoutOpts opts)
        {
            using (var osw = new ObjectSafeWrapper(treeId, repo))
            {
                int res = NativeMethods.git_checkout_tree(repo, osw.ObjectPtr, ref opts);
                Ensure.ZeroResult(res);
            }
        }

        public static void git_checkout_index(RepositorySafeHandle repo, GitObjectSafeHandle treeish, ref GitCheckoutOpts opts)
        {
            int res = NativeMethods.git_checkout_index(repo, treeish, ref opts);
            Ensure.ZeroResult(res);
        }

        #endregion

        #region git_cherry_pick_

        internal static void git_cherrypick(RepositorySafeHandle repo, ObjectId commit, GitCherryPickOptions options)
        {
            using (var nativeCommit = git_object_lookup(repo, commit, GitObjectType.Commit))
            {
                int res = NativeMethods.git_cherrypick(repo, nativeCommit, options);
                Ensure.ZeroResult(res);
            }
        }
        #endregion

        #region git_clone_

        public static RepositorySafeHandle git_clone(
            string url,
            string workdir,
            ref GitCloneOptions opts)
        {
            RepositorySafeHandle repo;
            int res = NativeMethods.git_clone(out repo, url, workdir, ref opts);
            Ensure.ZeroResult(res);
            return repo;
        }

        #endregion

        #region git_commit_

        public static Signature git_commit_author(GitObjectSafeHandle obj)
        {
            return new Signature(NativeMethods.git_commit_author(obj));
        }

        public static Signature git_commit_committer(GitObjectSafeHandle obj)
        {
            return new Signature(NativeMethods.git_commit_committer(obj));
        }

        public static ObjectId git_commit_create(
            RepositorySafeHandle repo,
            string referenceName,
            Signature author,
            Signature committer,
            string message,
            Tree tree,
            GitOid[] parentIds)
        {
            using (SignatureSafeHandle authorHandle = author.BuildHandle())
            using (SignatureSafeHandle committerHandle = committer.BuildHandle())
            using (var parentPtrs = new ArrayMarshaler<GitOid>(parentIds))
            {
                GitOid commitOid;

                var treeOid = tree.Id.Oid;

                int res = NativeMethods.git_commit_create_from_ids(out commitOid,
                                                                   repo,
                                                                   referenceName,
                                                                   authorHandle,
                                                                   committerHandle,
                                                                   null,
                                                                   message,
                                                                   ref treeOid,
                                                                   (UIntPtr)parentPtrs.Count,
                                                                   parentPtrs.ToArray());

                Ensure.ZeroResult(res);

                return commitOid;
            }
        }

        public static string git_commit_message(GitObjectSafeHandle obj)
        {
            return NativeMethods.git_commit_message(obj);
        }

        public static string git_commit_summary(GitObjectSafeHandle obj)
        {
            return NativeMethods.git_commit_summary(obj);
        }

        public static string git_commit_message_encoding(GitObjectSafeHandle obj)
        {
            return NativeMethods.git_commit_message_encoding(obj);
        }

        public static ObjectId git_commit_parent_id(GitObjectSafeHandle obj, uint i)
        {
            return NativeMethods.git_commit_parent_id(obj, i).MarshalAsObjectId();
        }

        public static int git_commit_parentcount(RepositorySafeHandle repo, ObjectId id)
        {
            using (var obj = new ObjectSafeWrapper(id, repo))
            {
                return git_commit_parentcount(obj);
            }
        }

        public static int git_commit_parentcount(ObjectSafeWrapper obj)
        {
            return (int)NativeMethods.git_commit_parentcount(obj.ObjectPtr);
        }

        public static ObjectId git_commit_tree_id(GitObjectSafeHandle obj)
        {
            return NativeMethods.git_commit_tree_id(obj).MarshalAsObjectId();
        }

        #endregion

        #region git_config_

        public static void git_config_add_file_ondisk(ConfigurationSafeHandle config, FilePath path, ConfigurationLevel level)
        {
            int res = NativeMethods.git_config_add_file_ondisk(config, path, (uint)level, true);
            Ensure.ZeroResult(res);
        }

        public static bool git_config_delete(ConfigurationSafeHandle config, string name)
        {
            int res = NativeMethods.git_config_delete_entry(config, name);

            if (res == (int)GitErrorCode.NotFound)
            {
                return false;
            }

            Ensure.ZeroResult(res);
            return true;
        }

        const string anyValue = ".*";

        public static bool git_config_delete_multivar(ConfigurationSafeHandle config, string name)
        {
            int res = NativeMethods.git_config_delete_multivar(config, name, anyValue);

            if (res == (int)GitErrorCode.NotFound)
            {
                return false;
            }

            Ensure.ZeroResult(res);
            return true;
        }

        public static FilePath git_config_find_global()
        {
            return ConvertPath(NativeMethods.git_config_find_global);
        }

        public static FilePath git_config_find_system()
        {
            return ConvertPath(NativeMethods.git_config_find_system);
        }

        public static FilePath git_config_find_xdg()
        {
            return ConvertPath(NativeMethods.git_config_find_xdg);
        }

        public static void git_config_free(IntPtr config)
        {
            NativeMethods.git_config_free(config);
        }

        public static void git_config_entry_free(IntPtr entry)
        {
            NativeMethods.git_config_entry_free(entry);
        }

        public static ConfigurationEntry<T> git_config_get_entry<T>(ConfigurationSafeHandle config, string key)
        {
            GitConfigEntryHandle handle = null;

            if (!configurationParser.ContainsKey(typeof(T)))
            {
                throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "Generic Argument of type '{0}' is not supported.", typeof(T).FullName));
            }

            GitConfigEntry entry;

            try
            {
                var res = NativeMethods.git_config_get_entry(out handle, config, key);
                if (res == (int)GitErrorCode.NotFound)
                {
                    return null;
                }

                Ensure.ZeroResult(res);

                entry = handle.MarshalAsGitConfigEntry();
            }
            finally
            {
                handle.SafeDispose();
            }

            return new ConfigurationEntry<T>(LaxUtf8Marshaler.FromNative(entry.namePtr),
                                             (T)configurationParser[typeof(T)](LaxUtf8Marshaler.FromNative(entry.valuePtr)),
                                             (ConfigurationLevel)entry.level);
        }

        public static ConfigurationSafeHandle git_config_new()
        {
            ConfigurationSafeHandle handle;
            int res = NativeMethods.git_config_new(out handle);
            Ensure.ZeroResult(res);

            return handle;
        }

        public static ConfigurationSafeHandle git_config_open_level(ConfigurationSafeHandle parent, ConfigurationLevel level)
        {
            ConfigurationSafeHandle handle;
            int res = NativeMethods.git_config_open_level(out handle, parent, (uint)level);

            if (res == (int)GitErrorCode.NotFound)
            {
                return null;
            }

            Ensure.ZeroResult(res);

            return handle;
        }

        public static bool git_config_parse_bool(string value)
        {
            bool outVal;
            var res = NativeMethods.git_config_parse_bool(out outVal, value);

            Ensure.ZeroResult(res);
            return outVal;
        }

        public static int git_config_parse_int32(string value)
        {
            int outVal;
            var res = NativeMethods.git_config_parse_int32(out outVal, value);

            Ensure.ZeroResult(res);
            return outVal;
        }

        public static long git_config_parse_int64(string value)
        {
            long outVal;
            var res = NativeMethods.git_config_parse_int64(out outVal, value);

            Ensure.ZeroResult(res);
            return outVal;
        }

        public static void git_config_set_bool(ConfigurationSafeHandle config, string name, bool value)
        {
            int res = NativeMethods.git_config_set_bool(config, name, value);
            Ensure.ZeroResult(res);
        }

        public static void git_config_set_int32(ConfigurationSafeHandle config, string name, int value)
        {
            int res = NativeMethods.git_config_set_int32(config, name, value);
            Ensure.ZeroResult(res);
        }

        public static void git_config_set_int64(ConfigurationSafeHandle config, string name, long value)
        {
            int res = NativeMethods.git_config_set_int64(config, name, value);
            Ensure.ZeroResult(res);
        }

        public static void git_config_set_string(ConfigurationSafeHandle config, string name, string value)
        {
            int res = NativeMethods.git_config_set_string(config, name, value);
            Ensure.ZeroResult(res);
        }

        public static ICollection<TResult> git_config_foreach<TResult>(
            ConfigurationSafeHandle config,
            Func<IntPtr, TResult> resultSelector)
        {
            return git_foreach(resultSelector, c => NativeMethods.git_config_foreach(config, (e, p) => c(e, p), IntPtr.Zero));
        }

        public static IEnumerable<ConfigurationEntry<string>> git_config_iterator_glob(
            ConfigurationSafeHandle config,
            string regexp,
            Func<IntPtr, ConfigurationEntry<string>> resultSelector)
        {
            return git_iterator((out ConfigurationIteratorSafeHandle iter) =>
                                    NativeMethods.git_config_iterator_glob_new(out iter, config, regexp),
                                (ConfigurationIteratorSafeHandle iter, out SafeHandleBase handle, out int res) =>
                                    {
                                        handle = null;

                                        IntPtr entry;
                                        res = NativeMethods.git_config_next(out entry, iter);
                                        return new { EntryPtr = entry };
                                    },
                                (handle, payload) =>
                                    resultSelector(payload.EntryPtr));
        }

        public static void git_config_iterator_free(IntPtr iter)
        {
            NativeMethods.git_config_iterator_free(iter);
        }

        public static ConfigurationSafeHandle git_config_snapshot(ConfigurationSafeHandle config)
        {
            ConfigurationSafeHandle handle;
            int res = NativeMethods.git_config_snapshot(out handle, config);
            Ensure.ZeroResult(res);

            return handle;
        }

        #endregion

        #region git_describe_

        public static string git_describe_commit(
            RepositorySafeHandle repo,
            ObjectId committishId,
            DescribeOptions options)
        {
            Ensure.ArgumentPositiveInt32(options.MinimumCommitIdAbbreviatedSize, "options.MinimumCommitIdAbbreviatedSize");

            using (var osw = new ObjectSafeWrapper(committishId, repo))
            {
                GitDescribeOptions opts = new GitDescribeOptions
                {
                    Version = 1,
                    DescribeStrategy = options.Strategy,
                    MaxCandidatesTags = 10,
                    OnlyFollowFirstParent = options.OnlyFollowFirstParent,
                    ShowCommitOidAsFallback = options.UseCommitIdAsFallback,
                };

                DescribeResultSafeHandle describeHandle = null;

                try
                {
                    int res = NativeMethods.git_describe_commit(out describeHandle, osw.ObjectPtr, ref opts);
                    Ensure.ZeroResult(res);

                    using (var buf = new GitBuf())
                    {
                        GitDescribeFormatOptions formatOptions = new GitDescribeFormatOptions
                        {
                            Version = 1,
                            MinAbbreviatedSize = (uint)options.MinimumCommitIdAbbreviatedSize,
                            AlwaysUseLongFormat = options.AlwaysRenderLongFormat,
                        };

                        res = NativeMethods.git_describe_format(buf, describeHandle, ref formatOptions);
                        Ensure.ZeroResult(res);

                        describeHandle.Dispose();
                        return LaxUtf8Marshaler.FromNative(buf.ptr);
                    }
                }
                finally
                {
                    if (describeHandle != null)
                    {
                        describeHandle.Dispose();
                    }
                }
            }
        }

        public static void git_describe_free(IntPtr iter)
        {
            NativeMethods.git_describe_result_free(iter);
        }

        #endregion

        #region git_diff_

        public static void git_diff_blobs(
            RepositorySafeHandle repo,
            ObjectId oldBlob,
            ObjectId newBlob,
            GitDiffOptions options,
            NativeMethods.git_diff_file_cb fileCallback,
            NativeMethods.git_diff_hunk_cb hunkCallback,
            NativeMethods.git_diff_line_cb lineCallback)
        {
            using (var osw1 = new ObjectSafeWrapper(oldBlob, repo, true))
            using (var osw2 = new ObjectSafeWrapper(newBlob, repo, true))
            {
                int res = NativeMethods.git_diff_blobs(osw1.ObjectPtr,
                                                       null,
                                                       osw2.ObjectPtr,
                                                       null,
                                                       options,
                                                       fileCallback,
                                                       null,
                                                       hunkCallback,
                                                       lineCallback,
                                                       IntPtr.Zero);

                Ensure.ZeroResult(res);
            }
        }

        public static void git_diff_foreach(
            DiffSafeHandle diff,
            NativeMethods.git_diff_file_cb fileCallback,
            NativeMethods.git_diff_hunk_cb hunkCallback,
            NativeMethods.git_diff_line_cb lineCallback)
        {
            int res = NativeMethods.git_diff_foreach(diff, fileCallback, null, hunkCallback, lineCallback, IntPtr.Zero);
            Ensure.ZeroResult(res);
        }

        public static DiffSafeHandle git_diff_tree_to_index(
            RepositorySafeHandle repo,
            IndexSafeHandle index,
            ObjectId oldTree,
            GitDiffOptions options)
        {
            using (var osw = new ObjectSafeWrapper(oldTree, repo, true))
            {
                DiffSafeHandle diff;
                int res = NativeMethods.git_diff_tree_to_index(out diff, repo, osw.ObjectPtr, index, options);
                Ensure.ZeroResult(res);

                return diff;
            }
        }

        public static void git_diff_free(IntPtr diff)
        {
            NativeMethods.git_diff_free(diff);
        }

        public static void git_diff_merge(DiffSafeHandle onto, DiffSafeHandle from)
        {
            int res = NativeMethods.git_diff_merge(onto, from);
            Ensure.ZeroResult(res);
        }

        public static DiffSafeHandle git_diff_tree_to_tree(
            RepositorySafeHandle repo,
            ObjectId oldTree,
            ObjectId newTree,
            GitDiffOptions options)
        {
            using (var osw1 = new ObjectSafeWrapper(oldTree, repo, true))
            using (var osw2 = new ObjectSafeWrapper(newTree, repo, true))
            {
                DiffSafeHandle diff;
                int res = NativeMethods.git_diff_tree_to_tree(out diff, repo, osw1.ObjectPtr, osw2.ObjectPtr, options);
                Ensure.ZeroResult(res);

                return diff;
            }
        }

        public static DiffSafeHandle git_diff_index_to_workdir(
            RepositorySafeHandle repo,
            IndexSafeHandle index,
            GitDiffOptions options)
        {
            DiffSafeHandle diff;
            int res = NativeMethods.git_diff_index_to_workdir(out diff, repo, index, options);
            Ensure.ZeroResult(res);

            return diff;
        }

        public static DiffSafeHandle git_diff_tree_to_workdir(
           RepositorySafeHandle repo,
           ObjectId oldTree,
           GitDiffOptions options)
        {
            using (var osw = new ObjectSafeWrapper(oldTree, repo, true))
            {
                DiffSafeHandle diff;
                int res = NativeMethods.git_diff_tree_to_workdir(out diff, repo, osw.ObjectPtr, options);
                Ensure.ZeroResult(res);

                return diff;
            }
        }

        public static void git_diff_find_similar(DiffSafeHandle diff, GitDiffFindOptions options)
        {
            int res = NativeMethods.git_diff_find_similar(diff, options);
            Ensure.ZeroResult(res);
        }

        public static int git_diff_num_deltas(DiffSafeHandle diff)
        {
            return (int)NativeMethods.git_diff_num_deltas(diff);
        }

        public static GitDiffDelta git_diff_get_delta(DiffSafeHandle diff, int idx)
        {
            return NativeMethods.git_diff_get_delta(diff, (UIntPtr)idx).MarshalAs<GitDiffDelta>(false);
        }

        #endregion

        #region git_filter_

        public static void git_filter_register(string name, IntPtr filterPtr, int priority)
        {
            int res = NativeMethods.git_filter_register(name, filterPtr, priority);
            if (res == (int)GitErrorCode.Exists)
            {
                throw new EntryExistsException("A filter with the name '{0}' is already registered", name);
            }
            Ensure.ZeroResult(res);
        }

        public static void git_filter_unregister(string name)
        {
            int res = NativeMethods.git_filter_unregister(name);
            Ensure.ZeroResult(res);
        }

        public static FilterMode git_filter_source_mode(IntPtr filterSource)
        {
            var res = NativeMethods.git_filter_source_mode(filterSource);
            return (FilterMode)res;
        }

        #endregion

        #region git_graph_

        public static Tuple<int?, int?> git_graph_ahead_behind(RepositorySafeHandle repo, Commit first, Commit second)
        {
            if (first == null || second == null)
            {
                return new Tuple<int?, int?>(null, null);
            }

            GitOid oid1 = first.Id.Oid;
            GitOid oid2 = second.Id.Oid;

            UIntPtr ahead;
            UIntPtr behind;

            int res = NativeMethods.git_graph_ahead_behind(out ahead, out behind, repo, ref oid1, ref oid2);

            Ensure.ZeroResult(res);

            return new Tuple<int?, int?>((int)ahead, (int)behind);
        }

        public static bool git_graph_descendant_of(RepositorySafeHandle repo, ObjectId commitId, ObjectId ancestorId)
        {
            GitOid oid1 = commitId.Oid;
            GitOid oid2 = ancestorId.Oid;
            int res = NativeMethods.git_graph_descendant_of(repo, ref oid1, ref oid2);

            Ensure.BooleanResult(res);

            return (res == 1);
        }

        #endregion

        #region git_ignore_

        public static void git_ignore_add_rule(RepositorySafeHandle repo, string rules)
        {
            int res = NativeMethods.git_ignore_add_rule(repo, rules);
            Ensure.ZeroResult(res);
        }

        public static void git_ignore_clear_internal_rules(RepositorySafeHandle repo)
        {
            int res = NativeMethods.git_ignore_clear_internal_rules(repo);
            Ensure.ZeroResult(res);
        }

        public static bool git_ignore_path_is_ignored(RepositorySafeHandle repo, string path)
        {
            int ignored;
            int res = NativeMethods.git_ignore_path_is_ignored(out ignored, repo, path);
            Ensure.ZeroResult(res);

            return (ignored != 0);
        }

        #endregion

        #region git_index_

        public static void git_index_add(IndexSafeHandle index, GitIndexEntry entry)
        {
            int res = NativeMethods.git_index_add(index, entry);
            Ensure.ZeroResult(res);
        }

        public static void git_index_add_bypath(IndexSafeHandle index, FilePath path)
        {
            int res = NativeMethods.git_index_add_bypath(index, path);
            Ensure.ZeroResult(res);
        }

        public static Conflict git_index_conflict_get(
            IndexSafeHandle index,
            FilePath path)
        {
            IndexEntrySafeHandle ancestor, ours, theirs;

            int res = NativeMethods.git_index_conflict_get(out ancestor,
                                                           out ours,
                                                           out theirs,
                                                           index,
                                                           path);

            if (res == (int)GitErrorCode.NotFound)
            {
                return null;
            }

            Ensure.ZeroResult(res);

            return new Conflict(IndexEntry.BuildFromPtr(ancestor),
                                IndexEntry.BuildFromPtr(ours),
                                IndexEntry.BuildFromPtr(theirs));
        }

        public static ConflictIteratorSafeHandle git_index_conflict_iterator_new(IndexSafeHandle index)
        {
            ConflictIteratorSafeHandle iter;
            int res = NativeMethods.git_index_conflict_iterator_new(out iter, index);
            Ensure.ZeroResult(res);

            return iter;
        }

        public static Conflict git_index_conflict_next(ConflictIteratorSafeHandle iterator)
        {
            IndexEntrySafeHandle ancestor, ours, theirs;

            int res = NativeMethods.git_index_conflict_next(out ancestor, out ours, out theirs, iterator);

            if (res == (int)GitErrorCode.IterOver)
            {
                return null;
            }

            Ensure.ZeroResult(res);

            using (ancestor)
            using (ours)
            using (theirs)
            {
                return new Conflict(IndexEntry.BuildFromPtr(ancestor),
                                    IndexEntry.BuildFromPtr(ours),
                                    IndexEntry.BuildFromPtr(theirs));
            }
        }

        public static void git_index_conflict_iterator_free(IntPtr iterator)
        {
            NativeMethods.git_index_conflict_iterator_free(iterator);
        }

        public static int git_index_entrycount(IndexSafeHandle index)
        {
            return NativeMethods.git_index_entrycount(index)
                .ConvertToInt();
        }

        public static StageLevel git_index_entry_stage(IndexEntrySafeHandle index)
        {
            return (StageLevel)NativeMethods.git_index_entry_stage(index);
        }

        public static void git_index_free(IntPtr index)
        {
            NativeMethods.git_index_free(index);
        }

        public static IndexEntrySafeHandle git_index_get_byindex(IndexSafeHandle index, UIntPtr n)
        {
            return NativeMethods.git_index_get_byindex(index, n);
        }