NativeMethods.cs

using System;
using System.IO;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.ConstrainedExecution;
using System.Runtime.InteropServices;
using LibGit2Sharp.Core.Handles;

// Restrict the set of directories where the native library is loaded from to safe directories.
[assembly: DefaultDllImportSearchPaths(DllImportSearchPath.AssemblyDirectory | DllImportSearchPath.ApplicationDirectory | DllImportSearchPath.SafeDirectories)]

namespace LibGit2Sharp.Core
{
    internal static class NativeMethods
    {
        public const uint GIT_PATH_MAX = 4096;
        private const string libgit2 = NativeDllName.Name;

        // An object tied to the lifecycle of the NativeMethods static class.
        // This will handle initialization and shutdown of the underlying
        // native library.
        private static NativeShutdownObject shutdownObject;

        static NativeMethods()
        {
            if (Platform.IsRunningOnNetFramework() || Platform.IsRunningOnNetCore())
            {
                // Use NativeLibrary when available.
                if (!TryUseNativeLibrary())
                {
                    // NativeLibrary is not available, fall back.

                    // Use GlobalSettings.NativeLibraryPath when set.
                    // Try to load the .dll from the path explicitly.
                    // If this call succeeds further DllImports will find the library loaded and not attempt to load it again.
                    // If it fails the next DllImport will load the library from safe directories.
                    string nativeLibraryPath = GetGlobalSettingsNativeLibraryPath();

                    if (nativeLibraryPath != null)
                    {
                        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))

                        {
                            LoadWindowsLibrary(nativeLibraryPath);
                        }
                        else
                        {
                            LoadUnixLibrary(nativeLibraryPath, RTLD_NOW);
                        }
                    }
                }
            }

            InitializeNativeLibrary();
        }

        private static string GetGlobalSettingsNativeLibraryPath()
        {
            string nativeLibraryDir = GlobalSettings.GetAndLockNativeLibraryPath();

            if (nativeLibraryDir == null)
            {
                return null;
            }

            return Path.Combine(nativeLibraryDir, libgit2 + Platform.GetNativeLibraryExtension());
        }

#if NETFRAMEWORK
        private static bool TryUseNativeLibrary() => false;
#else
        private static bool TryUseNativeLibrary()
        {
            NativeLibrary.SetDllImportResolver(typeof(NativeMethods).Assembly, ResolveDll);

            return true;
        }

        private static IntPtr ResolveDll(string libraryName, Assembly assembly, DllImportSearchPath? searchPath)
        {
            IntPtr handle = IntPtr.Zero;

            if (libraryName == libgit2)
            {
                // Use GlobalSettings.NativeLibraryPath when set.
                string nativeLibraryPath = GetGlobalSettingsNativeLibraryPath();

                if (nativeLibraryPath != null && NativeLibrary.TryLoad(nativeLibraryPath, out handle))
                {
                    return handle;
                }

                // Use Default DllImport resolution.
                if (NativeLibrary.TryLoad(libraryName, assembly, searchPath, out handle))
                {
                    return handle;
                }

                // We carry a number of .so files for Linux which are linked against various
                // libc/OpenSSL libraries. Try them out.
                if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
                {
                    // The libraries are located at 'runtimes/<rid>/native/lib{libraryName}.so'
                    // The <rid> ends with the processor architecture. e.g. fedora-x64.
                    string assemblyDirectory = Path.GetDirectoryName(typeof(NativeMethods).Assembly.Location);
                    string processorArchitecture = RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant();
                    string runtimesDirectory = Path.Combine(assemblyDirectory, "runtimes");

                    if (Directory.Exists(runtimesDirectory))
                    {
                        foreach (var runtimeFolder in Directory.GetDirectories(runtimesDirectory, $"*-{processorArchitecture}"))
                        {
                            string libPath = Path.Combine(runtimeFolder, "native", $"lib{libraryName}.so");

                            if (NativeLibrary.TryLoad(libPath, out handle))
                            {
                                return handle;
                            }
                        }
                    }
                }
            }

            return handle;
        }
#endif

        public const int RTLD_NOW = 0x002;

        [DllImport("libdl", EntryPoint = "dlopen")]
        private static extern IntPtr LoadUnixLibrary(string path, int flags);

        [DllImport("kernel32", EntryPoint = "LoadLibrary")]
        private static extern IntPtr LoadWindowsLibrary(string path);

        // Avoid inlining this method because otherwise mono's JITter may try
        // to load the library _before_ we've configured the path.
        [MethodImpl(MethodImplOptions.NoInlining)]
        private static void InitializeNativeLibrary()
        {
            int initCounter;
            try
            {
            }
            finally // avoid thread aborts
            {
                // Initialization can be called multiple times as long as there is a corresponding shutdown to each initialization.
                initCounter = git_libgit2_init();
                shutdownObject = new NativeShutdownObject();
            }

            // Configure the OpenSSL locking on the first initialization of the library in the current process.
            if (initCounter == 1)
            {
                git_openssl_set_locking();
            }
        }

        // Shutdown the native library in a finalizer.
        private sealed class NativeShutdownObject : CriticalFinalizerObject
        {
            ~NativeShutdownObject()
            {
                git_libgit2_shutdown();
            }
        }

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe GitError* git_error_last();

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_error_set_str(
            GitErrorCategory error_class,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string errorString);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern void git_error_set_oom();

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UInt32 git_blame_get_hunk_count(git_blame* blame);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_blame_hunk* git_blame_get_hunk_byindex(
            git_blame* blame, UInt32 index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_blame_file(
            out git_blame* blame,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path,
            git_blame_options options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_blame_free(git_blame* blame);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_blob_create_from_disk(
            ref GitOid id,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_blob_create_from_workdir(
            ref GitOid id,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath relative_path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_blob_create_from_stream(
            out IntPtr stream,
            git_repository* repositoryPtr,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string hintpath);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_blob_create_from_stream_commit(
            ref GitOid oid,
            IntPtr stream);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_blob_filtered_content(
            GitBuf buf,
            git_object* blob,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string as_path,
            [MarshalAs(UnmanagedType.Bool)] bool check_for_binary_data);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe IntPtr git_blob_rawcontent(git_object* blob);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe Int64 git_blob_rawsize(git_object* blob);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_branch_create_from_annotated(
            out git_reference* ref_out,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string branch_name,
            git_annotated_commit* target,
            [MarshalAs(UnmanagedType.Bool)] bool force);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_branch_delete(
            git_reference* reference);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal delegate int branch_foreach_callback(
            IntPtr branch_name,
            GitBranchType branch_type,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern void git_branch_iterator_free(
            IntPtr iterator);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_branch_iterator_new(
            out IntPtr iter_out,
            IntPtr repo,
            GitBranchType branch_type);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_branch_move(
            out git_reference* ref_out,
            git_reference* reference,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string new_branch_name,
            [MarshalAs(UnmanagedType.Bool)] bool force);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_branch_next(
            out IntPtr ref_out,
            out GitBranchType type_out,
            IntPtr iter);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_branch_remote_name(
            GitBuf buf,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string canonical_branch_name);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal delegate int commit_signing_callback(
            IntPtr signature,
            IntPtr signature_field,
            IntPtr commit_content,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_rebase_init(
            out git_rebase* rebase,
            git_repository* repo,
            git_annotated_commit* branch,
            git_annotated_commit* upstream,
            git_annotated_commit* onto,
            GitRebaseOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_rebase_open(
            out git_rebase* rebase,
            git_repository* repo,
            GitRebaseOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UIntPtr git_rebase_operation_entrycount(
            git_rebase* rebase);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UIntPtr git_rebase_operation_current(
            git_rebase* rebase);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_rebase_operation* git_rebase_operation_byindex(
            git_rebase* rebase,
            UIntPtr index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_rebase_next(
            out git_rebase_operation* operation,
            git_rebase* rebase);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_rebase_commit(
            ref GitOid id,
            git_rebase* rebase,
            git_signature* author,
            git_signature* committer,
            IntPtr message_encoding,
            IntPtr message);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_rebase_abort(
            git_rebase* rebase);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_rebase_finish(
            git_rebase* repo,
            git_signature* signature);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_rebase_free(git_rebase* rebase);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_remote_rename(
            ref GitStrArray problems,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string old_name,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string new_name);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal delegate int git_remote_rename_problem_cb(
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))] string problematic_refspec,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_branch_upstream_name(
            GitBuf buf,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string referenceName);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern void git_buf_dispose(GitBuf buf);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_checkout_tree(
            git_repository* repo,
            git_object* treeish,
            ref GitCheckoutOpts opts);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_checkout_index(
            git_repository* repo,
            git_object* treeish,
            ref GitCheckoutOpts opts);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_clone(
            out git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string origin_url,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath workdir_path,
            ref GitCloneOptions opts);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_signature* git_commit_author(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_signature* git_commit_committer(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_commit_create_from_ids(
            out GitOid id,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string updateRef,
            git_signature* author,
            git_signature* committer,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string encoding,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string message,
            ref GitOid tree,
            UIntPtr parentCount,
            [MarshalAs(UnmanagedType.LPArray)][In] IntPtr[] parents);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_commit_create_buffer(
            GitBuf res,
            git_repository* repo,
            git_signature* author,
            git_signature* committer,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string encoding,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string message,
            git_object* tree,
            UIntPtr parent_count,
            IntPtr* parents /* git_commit** originally */);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_commit_create_with_signature(
            out GitOid id,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string commit_content,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string signature,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string signature_field);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))]
        internal static extern unsafe string git_commit_message(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))]
        internal static extern unsafe string git_commit_summary(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))]
        internal static extern unsafe string git_commit_message_encoding(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_oid* git_commit_parent_id(git_object* commit, uint n);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe uint git_commit_parentcount(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_oid* git_commit_tree_id(git_object* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_commit_extract_signature(
            GitBuf signature,
            GitBuf signed_data,
            git_repository* repo,
            ref GitOid commit_id,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string field);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_delete_entry(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_lock(out IntPtr txn, git_config* config);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_delete_multivar(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string regexp);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_set_multivar(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string regexp,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string value);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_find_global(GitBuf global_config_path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_find_system(GitBuf system_config_path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_find_xdg(GitBuf xdg_config_path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_find_programdata(GitBuf programdata_config_path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_config_free(git_config* cfg);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_config_entry_free(GitConfigEntry* entry);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_get_entry(
            out GitConfigEntry* entry,
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_add_file_ondisk(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath path,
            uint level,
            git_repository* repo,
            [MarshalAs(UnmanagedType.Bool)] bool force);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_new(out git_config* cfg);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_open_level(
            out git_config* cfg,
            git_config* parent,
            uint level);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_parse_bool(
            [MarshalAs(UnmanagedType.Bool)] out bool value,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string valueToParse);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_parse_int32(
            [MarshalAs(UnmanagedType.I4)] out int value,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string valueToParse);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_parse_int64(
            [MarshalAs(UnmanagedType.I8)] out long value,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string valueToParse);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_set_bool(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            [MarshalAs(UnmanagedType.Bool)] bool value);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_set_int32(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            int value);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_set_int64(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            long value);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_set_string(
            git_config* cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string value);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal delegate int config_foreach_callback(
            IntPtr entry,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_foreach(
            git_config* cfg,
            config_foreach_callback callback,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_iterator_glob_new(
            out IntPtr iter,
            IntPtr cfg,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string regexp);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_config_next(
            out IntPtr entry,
            IntPtr iter);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern void git_config_iterator_free(IntPtr iter);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_config_snapshot(out git_config* @out, git_config* config);

        // Ordinarily we would decorate the `url` parameter with the StrictUtf8Marshaler like we do everywhere
        // else, but apparently doing a native->managed callback with the 64-bit version of CLR 2.0 can
        // sometimes vomit when using a custom IMarshaler.  So yeah, don't do that.  If you need the url,
        // call StrictUtf8Marshaler.FromNative manually.  See the discussion here:
        // http://social.msdn.microsoft.com/Forums/en-US/netfx64bit/thread/1eb746c6-d695-4632-8a9e-16c4fa98d481
        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal delegate int git_cred_acquire_cb(
            out IntPtr cred,
            IntPtr url,
            IntPtr username_from_url,
            GitCredentialType allowed_types,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_cred_default_new(out IntPtr cred);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_cred_userpass_plaintext_new(
            out IntPtr cred,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string username,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string password);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern void git_cred_free(IntPtr cred);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_describe_commit(
            out git_describe_result* describe,
            git_object* committish,
            ref GitDescribeOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_describe_format(
            GitBuf buf,
            git_describe_result* describe,
            ref GitDescribeFormatOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_describe_result_free(git_describe_result* describe);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_diff_free(git_diff* diff);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_tree_to_tree(
            out git_diff* diff,
            git_repository* repo,
            git_object* oldTree,
            git_object* newTree,
            GitDiffOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_tree_to_index(
            out git_diff* diff,
            git_repository* repo,
            git_object* oldTree,
            git_index* index,
            GitDiffOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_merge(
            git_diff* onto,
            git_diff* from);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_index_to_workdir(
            out git_diff* diff,
            git_repository* repo,
            git_index* index,
            GitDiffOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_tree_to_workdir(
            out git_diff* diff,
            git_repository* repo,
            git_object* oldTree,
            GitDiffOptions options);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal unsafe delegate int git_diff_file_cb(
            [In] git_diff_delta* delta,
            float progress,
            IntPtr payload);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal unsafe delegate int git_diff_hunk_cb(
            [In] git_diff_delta* delta,
            [In] GitDiffHunk hunk,
            IntPtr payload);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal unsafe delegate int git_diff_line_cb(
            [In] git_diff_delta* delta,
            [In] GitDiffHunk hunk,
            [In] GitDiffLine line,
            IntPtr payload);

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        internal unsafe delegate int git_diff_binary_cb(
            [In] git_diff_delta* delta,
            [In] GitDiffBinary binary,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_blobs(
            git_object* oldBlob,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string old_as_path,
            git_object* newBlob,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string new_as_path,
            GitDiffOptions options,
            git_diff_file_cb fileCallback,
            git_diff_binary_cb binaryCallback,
            git_diff_hunk_cb hunkCallback,
            git_diff_line_cb lineCallback,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_foreach(
            git_diff* diff,
            git_diff_file_cb fileCallback,
            git_diff_binary_cb binaryCallback,
            git_diff_hunk_cb hunkCallback,
            git_diff_line_cb lineCallback,
            IntPtr payload);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_diff_find_similar(
            git_diff* diff,
            GitDiffFindOptions options);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UIntPtr git_diff_num_deltas(git_diff* diff);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_diff_delta* git_diff_get_delta(git_diff* diff, UIntPtr idx);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_filter_register(
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name,
            IntPtr gitFilter, int priority);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_filter_unregister(
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_filter_source_mode(git_filter_source* source);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_features();

        #region git_libgit2_opts

        // Bindings for git_libgit2_opts(int option, ...):
        // Currently only GIT_OPT_GET_SEARCH_PATH and GIT_OPT_SET_SEARCH_PATH are supported,
        // but other overloads could be added using a similar pattern.
        // CallingConvention.Cdecl is used to allow binding the the C varargs signature, and each possible call signature must be enumerated.
        // __argslist was an option, but is an undocumented feature that should likely not be used here.

        // git_libgit2_opts(GIT_OPT_GET_SEARCH_PATH, int level, git_buf *buf)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option, uint level, GitBuf buf);

        // git_libgit2_opts(GIT_OPT_SET_SEARCH_PATH, int level, const char *path)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option, uint level,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        // git_libgit2_opts(GIT_OPT_ENABLE_*, int enabled)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option, int enabled);

        // git_libgit2_opts(GIT_OPT_SET_USER_AGENT, const char *path)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        // git_libgit2_opts(GIT_OPT_GET_USER_AGENT, git_buf *buf)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option, GitBuf buf);

        // git_libgit2_opts(GIT_OPT_SET_EXTENSIONS, const char **extensions, size_t len)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option, IntPtr extensions, UIntPtr len);

        // git_libgit2_opts(GIT_OPT_GET_EXTENSIONS, git_strarray *out)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_libgit2_opts(int option, out GitStrArray extensions);
        #endregion

        #region git_libgit2_opts_osxarm64

        // For RID osx-arm64 the calling convention is different: we need to pad out to 8 arguments before varargs
        // (see discussion at https://github.com/dotnet/runtime/issues/48796)

        // git_libgit2_opts(GIT_OPT_GET_SEARCH_PATH, int level, git_buf *buf)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8, uint level, GitBuf buf);

        // git_libgit2_opts(GIT_OPT_SET_SEARCH_PATH, int level, const char *path)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8, uint level,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        // git_libgit2_opts(GIT_OPT_ENABLE_*, int enabled)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8, int enabled);

        // git_libgit2_opts(GIT_OPT_SET_USER_AGENT, const char *path)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        // git_libgit2_opts(GIT_OPT_GET_USER_AGENT, git_buf *buf)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8, GitBuf buf);

        // git_libgit2_opts(GIT_OPT_SET_EXTENSIONS, const char **extensions, size_t len)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8, IntPtr extensions, UIntPtr len);

        // git_libgit2_opts(GIT_OPT_GET_EXTENSIONS, git_strarray *out)
        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl, EntryPoint = "git_libgit2_opts")]
        internal static extern int git_libgit2_opts_osxarm64(int option, IntPtr nop2, IntPtr nop3, IntPtr nop4, IntPtr nop5, IntPtr nop6, IntPtr nop7, IntPtr nop8, out GitStrArray extensions);
        #endregion

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_graph_ahead_behind(out UIntPtr ahead, out UIntPtr behind, git_repository* repo, ref GitOid one, ref GitOid two);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_graph_descendant_of(
            git_repository* repo,
            ref GitOid commit,
            ref GitOid ancestor);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_ignore_add_rule(
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string rules);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_ignore_clear_internal_rules(git_repository* repo);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_ignore_path_is_ignored(
            out int ignored,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_add_bypath(
            git_index* index,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_add(
            git_index* index,
            git_index_entry* entry);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_conflict_get(
            out git_index_entry* ancestor,
            out git_index_entry* ours,
            out git_index_entry* theirs,
            git_index* index,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_conflict_iterator_new(
            out git_index_conflict_iterator* iterator,
            git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_conflict_next(
            out git_index_entry* ancestor,
            out git_index_entry* ours,
            out git_index_entry* theirs,
            git_index_conflict_iterator* iterator);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_index_conflict_iterator_free(
            git_index_conflict_iterator* iterator);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UIntPtr git_index_entrycount(git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_entry_stage(git_index_entry* indexentry);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_index_free(git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_index_entry* git_index_get_byindex(git_index* index, UIntPtr n);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_index_entry* git_index_get_bypath(
            git_index* index,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path,
            int stage);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_has_conflicts(git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UIntPtr git_index_name_entrycount(git_index* handle);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_index_name_entry* git_index_name_get_byindex(git_index* handle, UIntPtr n);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_open(
            out git_index* index,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath indexpath);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_read(
            git_index* index,
            [MarshalAs(UnmanagedType.Bool)] bool force);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_remove_bypath(
            git_index* index,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe UIntPtr git_index_reuc_entrycount(git_index* handle);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_index_reuc_entry* git_index_reuc_get_byindex(git_index* handle, UIntPtr n);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_index_reuc_entry* git_index_reuc_get_bypath(
            git_index* handle,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string path);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_write(git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_write_tree(out GitOid treeOid, git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_write_tree_to(out GitOid treeOid, git_index* index, git_repository* repo);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_read_tree(git_index* index, git_object* tree);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_index_clear(git_index* index);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_merge_base_many(
            out GitOid mergeBase,
            git_repository* repo,
            int length,
            [In] GitOid[] input_array);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_merge_base_octopus(
            out GitOid mergeBase,
            git_repository* repo,
            int length,
            [In] GitOid[] input_array);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_annotated_commit_from_ref(
            out git_annotated_commit* annotatedCommit,
            git_repository* repo,
            git_reference* reference);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_annotated_commit_from_fetchhead(
            out git_annotated_commit* annotatedCommit,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string branch_name,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string remote_url,
            ref GitOid oid);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_annotated_commit_from_revspec(
            out git_annotated_commit* annotatedCommit,
            git_repository* repo,
            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string revspec);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_annotated_commit_lookup(
            out git_annotated_commit* annotatedCommit,
            git_repository* repo,
            ref GitOid id);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe git_oid* git_annotated_commit_id(
            git_annotated_commit* annotatedCommit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_merge(
            git_repository* repo,
            [In] IntPtr[] their_heads,
            UIntPtr their_heads_len,
            ref GitMergeOpts merge_opts,
            ref GitCheckoutOpts checkout_opts);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_merge_commits(
            out git_index* index,
            git_repository* repo,
            git_object* our_commit,
            git_object* their_commit,
            ref GitMergeOpts merge_opts);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe int git_merge_analysis(
            out GitMergeAnalysis status_out,
            out GitMergePreference preference_out,
            git_repository* repo,
            [In] IntPtr[] their_heads,
            int their_heads_len);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern unsafe void git_annotated_commit_free(git_annotated_commit* commit);

        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
        internal static extern int git_message_prettify(