Merge pull request #6557 from libgit2/ethomson/shallow

Shallow (#6396) with some fixes from review

include/git2/errors.h

@@ -109,7 +109,8 @@ typedef enum {
 	GIT_ERROR_WORKTREE,
 	GIT_ERROR_SHA,
 	GIT_ERROR_HTTP,
-	GIT_ERROR_INTERNAL
+	GIT_ERROR_INTERNAL,
+	GIT_ERROR_GRAFTS
 } git_error_t;
 
 /**

include/git2/remote.h

@@ -702,6 +702,15 @@ typedef enum {
 	GIT_REMOTE_DOWNLOAD_TAGS_ALL
 } git_remote_autotag_option_t;
 
+/** Constants for fetch depth (shallowness of fetch). */
+typedef enum {
+	/** The fetch is "full" (not shallow). This is the default. */
+	GIT_FETCH_DEPTH_FULL = 0,
+
+	/** The fetch should "unshallow" and fetch missing data. */
+	GIT_FETCH_DEPTH_UNSHALLOW = 2147483647
+} git_fetch_depth_t;
+
 /**
  * Fetch options structure.
  *
@@ -744,6 +753,15 @@ typedef struct {
 	git_proxy_options proxy_opts;
 
 	/**
+	 * Depth of the fetch to perform, or `GIT_FETCH_DEPTH_FULL`
+	 * (or `0`) for full history, or `GIT_FETCH_DEPTH_UNSHALLOW`
+	 * to "unshallow" a shallow repository.
+	 *
+	 * The default is full (`GIT_FETCH_DEPTH_FULL` or `0`).
+	 */
+	int depth;
+
+	/**
 	 * Whether to allow off-site redirects.  If this is not
 	 * specified, the `http.followRedirects` configuration setting
 	 * will be consulted.

include/git2/sys/transport.h

@@ -25,6 +25,14 @@
 
 GIT_BEGIN_DECL
 
+typedef struct {
+	const git_remote_head * const *refs;
+	size_t refs_len;
+	git_oid *shallow_roots;
+	size_t shallow_roots_len;
+	int depth;
+} git_fetch_negotiation;
+
 struct git_transport {
 	unsigned int version; /**< The struct version */
 
@@ -96,8 +104,17 @@ struct git_transport {
 	int GIT_CALLBACK(negotiate_fetch)(
 		git_transport *transport,
 		git_repository *repo,
-		const git_remote_head * const *refs,
-		size_t count);
+		const git_fetch_negotiation *fetch_data);
+
+	/**
+	 * Return the shallow roots of the remote.
+	 *
+	 * This function may be called after a successful call to
+	 * `negotiate_fetch`.
+	 */
+	int GIT_CALLBACK(shallow_roots)(
+		git_oidarray *out,
+		git_transport *transport);
 
 	/**
 	 * Start downloading the packfile from the remote repository.

src/cli/cmd_clone.c

@@ -18,7 +18,7 @@
 
 #define COMMAND_NAME "clone"
 
-static char *branch, *remote_path, *local_path;
+static char *branch, *remote_path, *local_path, *depth;
 static int show_help, quiet, checkout = 1, bare;
 static bool local_path_exists;
 static cli_progress progress = CLI_PROGRESS_INIT;
@@ -36,6 +36,8 @@ static const cli_opt_spec opts[] = {
 	  CLI_OPT_USAGE_DEFAULT,   NULL,         "don't create a working directory" },
 	{ CLI_OPT_TYPE_VALUE,     "branch",      'b', &branch,      0,
 	  CLI_OPT_USAGE_DEFAULT,  "name",        "branch to check out" },
+	{ CLI_OPT_TYPE_VALUE,     "depth",       0,   &depth,       0,
+	  CLI_OPT_USAGE_DEFAULT,  "depth",       "commit depth to check out " },
 	{ CLI_OPT_TYPE_LITERAL },
 	{ CLI_OPT_TYPE_ARG,       "repository",   0,  &remote_path, 0,
 	  CLI_OPT_USAGE_REQUIRED, "repository",  "repository path" },
@@ -71,6 +73,22 @@ static char *compute_local_path(const char *orig_path)
 	return local_path;
 }
 
+static int compute_depth(const char *depth)
+{
+	int64_t i;
+	const char *endptr;
+
+	if (!depth)
+		return 0;
+
+	if (git__strntol64(&i, depth, strlen(depth), &endptr, 10) < 0 || i < 0 || i > INT_MAX || *endptr) {
+		fprintf(stderr, "fatal: depth '%s' is not valid.\n", depth);
+		exit(128);
+	}
+
+	return (int)i;
+}
+
 static bool validate_local_path(const char *path)
 {
 	if (!git_fs_path_exists(path))
@@ -127,11 +145,9 @@ int cmd_clone(int argc, char **argv)
 		goto done;
 	}
 
-	if (bare)
-		clone_opts.bare = 1;
-
-	if (branch)
-		clone_opts.checkout_branch = branch;
+	clone_opts.bare = !!bare;
+	clone_opts.checkout_branch = branch;
+	clone_opts.fetch_opts.depth = compute_depth(depth);
 
 	if (!checkout)
 		clone_opts.checkout_opts.checkout_strategy = GIT_CHECKOUT_NONE;

src/libgit2/clone.c

@@ -420,7 +420,9 @@ static int clone_into(
 
 	memcpy(&fetch_opts, opts, sizeof(git_fetch_options));
 	fetch_opts.update_fetchhead = 0;
-	fetch_opts.download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
+
+	if (!opts->depth)
+		fetch_opts.download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
 
 	if ((error = git_remote_connect_options__from_fetch_opts(&connect_opts, remote, &fetch_opts)) < 0)
 		goto cleanup;

src/libgit2/commit.c

@@ -22,6 +22,7 @@
 #include "object.h"
 #include "array.h"
 #include "oidarray.h"
+#include "grafts.h"
 
 void git_commit__free(void *_commit)
 {
@@ -427,10 +428,6 @@ static int commit_parse(
 		buffer += tree_len;
 	}
 
-	/*
-	 * TODO: commit grafts!
-	 */
-
 	while (git_object__parse_oid_header(&parent_id,
 			&buffer, buffer_end, "parent ",
 			opts->oid_type) == 0) {
@@ -532,16 +529,41 @@ int git_commit__parse_raw(
 	return commit_parse(commit, data, size, &parse_options);
 }
 
+static int assign_commit_parents_from_graft(git_commit *commit, git_commit_graft *graft) {
+	size_t idx;
+	git_oid *oid;
+
+	git_array_clear(commit->parent_ids);
+	git_array_init_to_size(commit->parent_ids, git_array_size(graft->parents));
+	git_array_foreach(graft->parents, idx, oid) {
+		git_oid *id = git_array_alloc(commit->parent_ids);
+		GIT_ERROR_CHECK_ALLOC(id);
+
+		git_oid_cpy(id, oid);
+	}
+
+	return 0;
+}
+
 int git_commit__parse_ext(
 	git_commit *commit,
 	git_odb_object *odb_obj,
 	git_commit__parse_options *parse_opts)
 {
-	return commit_parse(
-		commit,
-		git_odb_object_data(odb_obj),
-		git_odb_object_size(odb_obj),
-		parse_opts);
+	git_repository *repo = git_object_owner((git_object *)commit);
+	git_commit_graft *graft;
+	int error;
+
+	if ((error = commit_parse(commit, git_odb_object_data(odb_obj),
+				  git_odb_object_size(odb_obj), parse_opts)) < 0)
+		return error;
+
+	/* Perform necessary grafts */
+	if (git_grafts_get(&graft, repo->grafts, git_odb_object_id(odb_obj)) != 0 &&
+		git_grafts_get(&graft, repo->shallow_grafts, git_odb_object_id(odb_obj)) != 0)
+		return 0;
+
+	return assign_commit_parents_from_graft(commit, graft);
 }
 
 #define GIT_COMMIT_GETTER(_rvalue, _name, _return, _invalid) \

src/libgit2/fetch.c

@@ -20,6 +20,7 @@
 #include "netops.h"
 #include "repository.h"
 #include "refs.h"
+#include "transports/smart.h"
 
 static int maybe_want(git_remote *remote, git_remote_head *head, git_refspec *tagspec, git_remote_autotag_option_t tagopt)
 {
@@ -59,8 +60,10 @@ static int mark_local(git_remote *remote)
 		return -1;
 
 	git_vector_foreach(&remote->refs, i, head) {
-		/* If we have the object, mark it so we don't ask for it */
-		if (git_odb_exists(odb, &head->oid))
+		/* If we have the object, mark it so we don't ask for it.
+		   However if we are unshallowing, we need to ask for it
+		   even though the head exists locally. */
+		if (remote->nego.depth != INT_MAX && git_odb_exists(odb, &head->oid))
 			head->local = 1;
 		else
 			remote->need_pack = 1;
@@ -166,9 +169,15 @@ cleanup:
 int git_fetch_negotiate(git_remote *remote, const git_fetch_options *opts)
 {
 	git_transport *t = remote->transport;
+	int error;
 
 	remote->need_pack = 0;
 
+	if (opts) {
+		GIT_ASSERT_ARG(opts->depth >= 0);
+		remote->nego.depth = opts->depth;
+	}
+
 	if (filter_wants(remote, opts) < 0)
 		return -1;
 
@@ -180,20 +189,40 @@ int git_fetch_negotiate(git_remote *remote, const git_fetch_options *opts)
 	 * Now we have everything set up so we can start tell the
 	 * server what we want and what we have.
 	 */
-	return t->negotiate_fetch(t,
+	remote->nego.refs = (const git_remote_head * const *)remote->refs.contents;
+	remote->nego.refs_len = remote->refs.length;
+
+	if (git_repository__shallow_roots(&remote->nego.shallow_roots,
+	                                  &remote->nego.shallow_roots_len,
+	                                  remote->repo) < 0)
+		return -1;
+
+	error = t->negotiate_fetch(t,
 		remote->repo,
-		(const git_remote_head * const *)remote->refs.contents,
-		remote->refs.length);
+		&remote->nego);
+
+	git__free(remote->nego.shallow_roots);
+
+	return error;
 }
 
 int git_fetch_download_pack(git_remote *remote)
 {
+	git_oidarray shallow_roots = { NULL };
 	git_transport *t = remote->transport;
+	int error;
 
 	if (!remote->need_pack)
 		return 0;
 
-	return t->download_pack(t, remote->repo, &remote->stats);
+	if ((error = t->download_pack(t, remote->repo, &remote->stats)) != 0 ||
+	    (error = t->shallow_roots(&shallow_roots, t)) != 0)
+		return error;
+
+	error = git_repository__shallow_roots_write(remote->repo, &shallow_roots);
+
+	git_oidarray_dispose(&shallow_roots);
+	return error;
 }
 
 int git_fetch_options_init(git_fetch_options *opts, unsigned int version)

src/libgit2/grafts.c

+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "grafts.h"
+
+#include "futils.h"
+#include "oid.h"
+#include "oidarray.h"
+#include "parse.h"
+
+struct git_grafts {
+	/* Map of `git_commit_graft`s */
+	git_oidmap *commits;
+
+	/* Type of object IDs */
+	git_oid_t oid_type;
+
+	/* File backing the graft. NULL if it's an in-memory graft */
+	char *path;
+	unsigned char path_checksum[GIT_HASH_SHA256_SIZE];
+};
+
+int git_grafts_new(git_grafts **out, git_oid_t oid_type)
+{
+	git_grafts *grafts;
+
+	GIT_ASSERT_ARG(out && oid_type);
+
+	grafts = git__calloc(1, sizeof(*grafts));
+	GIT_ERROR_CHECK_ALLOC(grafts);
+
+	if ((git_oidmap_new(&grafts->commits)) < 0) {
+		git__free(grafts);
+		return -1;
+	}
+
+	grafts->oid_type = oid_type;
+
+	*out = grafts;
+	return 0;
+}
+
+int git_grafts_open(
+	git_grafts **out,
+	const char *path,
+	git_oid_t oid_type)
+{
+	git_grafts *grafts = NULL;
+	int error;
+
+	GIT_ASSERT_ARG(out && path && oid_type);
+
+	if ((error = git_grafts_new(&grafts, oid_type)) < 0)
+		goto error;
+
+	grafts->path = git__strdup(path);
+	GIT_ERROR_CHECK_ALLOC(grafts->path);
+
+	if ((error = git_grafts_refresh(grafts)) < 0)
+		goto error;
+
+	*out = grafts;
+
+error:
+	if (error < 0)
+		git_grafts_free(grafts);
+
+	return error;
+}
+
+int git_grafts_open_or_refresh(
+	git_grafts **out,
+	const char *path,
+	git_oid_t oid_type)
+{
+	GIT_ASSERT_ARG(out && path && oid_type);
+
+	return *out ? git_grafts_refresh(*out) : git_grafts_open(out, path, oid_type);
+}
+
+void git_grafts_free(git_grafts *grafts)
+{
+	if (!grafts)
+		return;
+	git__free(grafts->path);
+	git_grafts_clear(grafts);
+	git_oidmap_free(grafts->commits);
+	git__free(grafts);
+}
+
+void git_grafts_clear(git_grafts *grafts)
+{
+	git_commit_graft *graft;
+
+	if (!grafts)
+		return;
+
+	git_oidmap_foreach_value(grafts->commits, graft, {
+		git__free(graft->parents.ptr);
+		git__free(graft);
+	});
+
+	git_oidmap_clear(grafts->commits);
+}
+
+int git_grafts_refresh(git_grafts *grafts)
+{
+	git_str contents = GIT_STR_INIT;
+	int error, updated = 0;
+
+	GIT_ASSERT_ARG(grafts);
+
+	if (!grafts->path)
+		return 0;
+
+	if ((error = git_futils_readbuffer_updated(&contents, grafts->path,
+				grafts->path_checksum, &updated)) < 0) {
+
+		if (error == GIT_ENOTFOUND) {
+			git_grafts_clear(grafts);
+			error = 0;
+		}
+
+		goto cleanup;
+	}
+
+	if (!updated) {
+		goto cleanup;
+	}
+
+	if ((error = git_grafts_parse(grafts, contents.ptr, contents.size)) < 0)
+		goto cleanup;
+
+cleanup:
+	git_str_dispose(&contents);
+	return error;
+}
+
+int git_grafts_parse(git_grafts *grafts, const char *buf, size_t len)
+{
+	git_array_oid_t parents = GIT_ARRAY_INIT;
+	git_parse_ctx parser;
+	int error;
+
+	git_grafts_clear(grafts);
+
+	if ((error = git_parse_ctx_init(&parser, buf, len)) < 0)
+		goto error;
+
+	for (; parser.remain_len; git_parse_advance_line(&parser)) {
+		git_oid graft_oid;
+
+		if ((error = git_parse_advance_oid(&graft_oid, &parser, grafts->oid_type)) < 0) {
+			git_error_set(GIT_ERROR_GRAFTS, "invalid graft OID at line %" PRIuZ, parser.line_num);
+			goto error;
+		}
+
+		while (parser.line_len && git_parse_advance_expected(&parser, "\n", 1) != 0) {
+			git_oid *id = git_array_alloc(parents);
+			GIT_ERROR_CHECK_ALLOC(id);
+
+			if ((error = git_parse_advance_expected(&parser, " ", 1)) < 0 ||
+			    (error = git_parse_advance_oid(id, &parser, grafts->oid_type)) < 0) {
+				git_error_set(GIT_ERROR_GRAFTS, "invalid parent OID at line %" PRIuZ, parser.line_num);
+				goto error;
+			}
+		}
+
+		if ((error = git_grafts_add(grafts, &graft_oid, parents)) < 0)
+			goto error;
+
+		git_array_clear(parents);
+	}
+
+error:
+	git_array_clear(parents);
+	return error;
+}
+
+int git_grafts_add(git_grafts *grafts, const git_oid *oid, git_array_oid_t parents)
+{
+	git_commit_graft *graft;
+	git_oid *parent_oid;
+	int error;
+	size_t i;
+
+	GIT_ASSERT_ARG(grafts && oid);
+
+	graft = git__calloc(1, sizeof(*graft));
+	GIT_ERROR_CHECK_ALLOC(graft);
+
+	git_array_init_to_size(graft->parents, git_array_size(parents));
+	git_array_foreach(parents, i, parent_oid) {
+		git_oid *id = git_array_alloc(graft->parents);
+		GIT_ERROR_CHECK_ALLOC(id);
+
+		git_oid_cpy(id, parent_oid);
+	}
+	git_oid_cpy(&graft->oid, oid);
+
+	if ((error = git_grafts_remove(grafts, &graft->oid)) < 0 && error != GIT_ENOTFOUND)
+		goto cleanup;
+
+	if ((error = git_oidmap_set(grafts->commits, &graft->oid, graft)) < 0)
+		goto cleanup;
+
+	return 0;
+
+cleanup:
+	git_array_clear(graft->parents);
+	git__free(graft);
+	return error;
+}
+
+int git_grafts_remove(git_grafts *grafts, const git_oid *oid)
+{
+	git_commit_graft *graft;
+	int error;
+
+	GIT_ASSERT_ARG(grafts && oid);
+
+	if ((graft = git_oidmap_get(grafts->commits, oid)) == NULL)
+		return GIT_ENOTFOUND;
+
+	if ((error = git_oidmap_delete(grafts->commits, oid)) < 0)
+		return error;
+
+	git__free(graft->parents.ptr);
+	git__free(graft);
+
+	return 0;
+}
+
+int git_grafts_get(git_commit_graft **out, git_grafts *grafts, const git_oid *oid)
+{
+	GIT_ASSERT_ARG(out && grafts && oid);
+	if ((*out = git_oidmap_get(grafts->commits, oid)) == NULL)
+		return GIT_ENOTFOUND;
+	return 0;
+}
+
+int git_grafts_oids(git_oid **out, size_t *out_len, git_grafts *grafts)
+{
+	git_array_oid_t array = GIT_ARRAY_INIT;
+	const git_oid *oid;
+	size_t existing, i = 0;
+
+	GIT_ASSERT_ARG(out && grafts);
+
+	if ((existing = git_oidmap_size(grafts->commits)) > 0)
+		git_array_init_to_size(array, existing);
+
+	while (git_oidmap_iterate(NULL, grafts->commits, &i, &oid) == 0) {
+		git_oid *cpy = git_array_alloc(array);
+		GIT_ERROR_CHECK_ALLOC(cpy);
+		git_oid_cpy(cpy, oid);
+	}
+
+	*out = array.ptr;
+	*out_len = array.size;
+
+	return 0;
+}
+
+size_t git_grafts_size(git_grafts *grafts)
+{
+	return git_oidmap_size(grafts->commits);
+}

src/libgit2/grafts.h

+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_graft_h__
+#define INCLUDE_graft_h__
+
+#include "common.h"
+#include "oidarray.h"
+#include "oidmap.h"
+
+/** graft commit */
+typedef struct {
+	git_oid oid;
+	git_array_oid_t parents;
+} git_commit_graft;
+
+typedef struct git_grafts git_grafts;
+
+int git_grafts_new(git_grafts **out, git_oid_t oid_type);
+int git_grafts_open(git_grafts **out, const char *path, git_oid_t oid_type);
+int git_grafts_open_or_refresh(git_grafts **out, const char *path, git_oid_t oid_type);
+void git_grafts_free(git_grafts *grafts);
+void git_grafts_clear(git_grafts *grafts);
+
+int git_grafts_refresh(git_grafts *grafts);
+int git_grafts_parse(git_grafts *grafts, const char *buf, size_t len);
+int git_grafts_add(git_grafts *grafts, const git_oid *oid, git_array_oid_t parents);
+int git_grafts_remove(git_grafts *grafts, const git_oid *oid);
+int git_grafts_get(git_commit_graft **out, git_grafts *grafts, const git_oid *oid);
+int git_grafts_oids(git_oid **out, size_t *out_len, git_grafts *grafts);
+size_t git_grafts_size(git_grafts *grafts);
+
+#endif

src/libgit2/libgit2.c

@@ -13,6 +13,7 @@
 #include "cache.h"
 #include "common.h"
 #include "filter.h"
+#include "grafts.h"
 #include "hash.h"
 #include "index.h"
 #include "merge_driver.h"

src/libgit2/object.c

@@ -108,15 +108,13 @@ int git_object__from_raw(
 	return 0;
 }
 
-int git_object__from_odb_object(
+int git_object__init_from_odb_object(
 	git_object **object_out,
 	git_repository *repo,
 	git_odb_object *odb_obj,
 	git_object_t type)
 {
-	int error;
 	size_t object_size;
-	git_object_def *def;
 	git_object *object = NULL;
 
 	GIT_ASSERT_ARG(object_out);
@@ -143,6 +141,23 @@ int git_object__from_odb_object(
 	object->cached.size = odb_obj->cached.size;
 	object->repo = repo;
 
+	*object_out = object;
+	return 0;
+}
+
+int git_object__from_odb_object(
+	git_object **object_out,
+	git_repository *repo,
+	git_odb_object *odb_obj,
+	git_object_t type)
+{
+	int error;
+	git_object_def *def;
+	git_object *object = NULL;
+
+	if ((error = git_object__init_from_odb_object(&object, repo, odb_obj, type)) < 0)
+		return error;
+
 	/* Parse raw object data */
 	def = &git_objects_table[odb_obj->cached.type];
 	GIT_ASSERT(def->free && def->parse);

src/libgit2/object.h

@@ -36,6 +36,12 @@ int git_object__from_raw(
 	git_object_t object_type,
 	git_oid_t oid_type);
 
+int git_object__init_from_odb_object(
+	git_object **object_out,
+	git_repository *repo,
+	git_odb_object *odb_obj,
+	git_object_t type);
+
 int git_object__from_odb_object(
 	git_object **object_out,
 	git_repository *repo,

src/libgit2/oidarray.c

@@ -15,10 +15,17 @@ void git_oidarray_dispose(git_oidarray *arr)
 	git__free(arr->ids);
 }
 
-void git_oidarray__from_array(git_oidarray *arr, git_array_oid_t *array)
+void git_oidarray__from_array(git_oidarray *out, const git_array_oid_t *array)
 {
-	arr->count = array->size;
-	arr->ids = array->ptr;
+	out->count = array->size;
+	out->ids = array->ptr;
+}
+
+void git_oidarray__to_array(git_array_oid_t *out, const git_oidarray *array)
+{
+	out->ptr = array->ids;
+	out->size = array->count;
+	out->asize = array->count;
 }
 
 void git_oidarray__reverse(git_oidarray *arr)
@@ -33,6 +40,45 @@ void git_oidarray__reverse(git_oidarray *arr)
 	}
 }
 
+int git_oidarray__add(git_array_oid_t *arr, git_oid *id)
+{
+	git_oid *add, *iter;
+	size_t i;
+
+	git_array_foreach(*arr, i, iter) {
+		if (git_oid_cmp(iter, id) == 0)
+			return 0;
+	}
+
+	if ((add = git_array_alloc(*arr)) == NULL)
+		return -1;
+
+	git_oid_cpy(add, id);
+	return 0;
+}
+
+bool git_oidarray__remove(git_array_oid_t *arr, git_oid *id)
+{
+	bool found = false;
+	size_t remain, i;
+	git_oid *iter;
+
+	git_array_foreach(*arr, i, iter) {
+		if (git_oid_cmp(iter, id) == 0) {
+			arr->size--;
+			remain = arr->size - i;
+
+			if (remain > 0)
+				memmove(&arr->ptr[i], &arr->ptr[i+1], remain * sizeof(git_oid));
+
+			found = true;
+			break;
+		}
+	}
+
+	return found;
+}
+
 #ifndef GIT_DEPRECATE_HARD
 
 void git_oidarray_free(git_oidarray *arr)

src/libgit2/oidarray.h

@@ -15,6 +15,10 @@
 typedef git_array_t(git_oid) git_array_oid_t;
 
 extern void git_oidarray__reverse(git_oidarray *arr);
-extern void git_oidarray__from_array(git_oidarray *arr, git_array_oid_t *array);
+extern void git_oidarray__from_array(git_oidarray *out, const git_array_oid_t *array);
+extern void git_oidarray__to_array(git_array_oid_t *out, const git_oidarray *array);
+
+int git_oidarray__add(git_array_oid_t *arr, git_oid *id);
+bool git_oidarray__remove(git_array_oid_t *arr, git_oid *id);
 
 #endif

src/libgit2/remote.c

@@ -23,6 +23,7 @@
 #include "git2/types.h"
 #include "git2/oid.h"
 #include "git2/net.h"
+#include "transports/smart.h"
 
 #define CONFIG_URL_FMT "remote.%s.url"
 #define CONFIG_PUSHURL_FMT "remote.%s.pushurl"

src/libgit2/remote.h

@@ -38,6 +38,7 @@ struct git_remote {
 	git_remote_autotag_option_t download_tags;
 	int prune_refs;
 	int passed_refspecs;
+	git_fetch_negotiation nego;
 };
 
 int git_remote__urlfordirection(git_str *url_out, struct git_remote *remote, int direction, const git_remote_callbacks *callbacks);

src/libgit2/repository.c

@@ -15,6 +15,7 @@
 #include "buf.h"
 #include "common.h"
 #include "commit.h"
+#include "grafts.h"
 #include "tag.h"
 #include "blob.h"
 #include "futils.h"
@@ -151,6 +152,8 @@ int git_repository__cleanup(git_repository *repo)
 	git_repository_submodule_cache_clear(repo);
 	git_cache_clear(&repo->objects);
 	git_attr_cache_flush(repo);
+	git_grafts_free(repo->grafts);
+	git_grafts_free(repo->shallow_grafts);
 
 	set_config(repo, NULL);
 	set_index(repo, NULL);
@@ -842,6 +845,27 @@ out:
 	return error;
 }
 
+static int load_grafts(git_repository *repo)
+{
+	git_str path = GIT_STR_INIT;
+	int error;
+
+	if ((error = git_repository__item_path(&path, repo, GIT_REPOSITORY_ITEM_INFO)) < 0 ||
+	    (error = git_str_joinpath(&path, path.ptr, "grafts")) < 0 ||
+	    (error = git_grafts_open_or_refresh(&repo->grafts, path.ptr, repo->oid_type)) < 0)
+		goto error;
+
+	git_str_clear(&path);
+
+	if ((error = git_str_joinpath(&path, repo->gitdir, "shallow")) < 0 ||
+	    (error = git_grafts_open_or_refresh(&repo->shallow_grafts, path.ptr, repo->oid_type)) < 0)
+		goto error;
+
+error:
+	git_str_dispose(&path);
+	return error;
+}
+
 static int find_repo(
 	struct repo_paths *out,
 	const char *start_path,
@@ -1075,6 +1099,9 @@ int git_repository_open_ext(
 	if (error < 0)
 		goto cleanup;
 
+	if ((error = load_grafts(repo)) < 0)
+		goto cleanup;
+
 	if ((flags & GIT_REPOSITORY_OPEN_BARE) != 0) {
 		repo->is_bare = 1;
 	} else {
@@ -1604,6 +1631,22 @@ int git_repository_set_index(git_repository *repo, git_index *index)
 	return 0;
 }
 
+int git_repository_grafts__weakptr(git_grafts **out, git_repository *repo)
+{
+	GIT_ASSERT_ARG(out && repo);
+	GIT_ASSERT(repo->grafts);
+	*out = repo->grafts;
+	return 0;
+}
+
+int git_repository_shallow_grafts__weakptr(git_grafts **out, git_repository *repo)
+{
+	GIT_ASSERT_ARG(out && repo);
+	GIT_ASSERT(repo->shallow_grafts);
+	*out = repo->shallow_grafts;
+	return 0;
+}
+
 int git_repository_set_namespace(git_repository *repo, const char *namespace)
 {
 	git__free(repo->namespace);
@@ -3628,6 +3671,66 @@ int git_repository_state_cleanup(git_repository *repo)
 	return git_repository__cleanup_files(repo, state_files, ARRAY_SIZE(state_files));
 }
 
+int git_repository__shallow_roots(
+	git_oid **out,
+	size_t *out_len,
+	git_repository *repo)
+{
+	int error = 0;
+
+	if (!repo->shallow_grafts && (error = load_grafts(repo)) < 0)
+		return error;
+
+	if ((error = git_grafts_refresh(repo->shallow_grafts)) < 0)
+		return error;
+
+	if ((error = git_grafts_oids(out, out_len, repo->shallow_grafts)) < 0)
+		return error;
+
+	return 0;
+}
+
+int git_repository__shallow_roots_write(git_repository *repo, git_oidarray *roots)
+{
+	git_filebuf file = GIT_FILEBUF_INIT;
+	git_str path = GIT_STR_INIT;
+	char oid_str[GIT_OID_MAX_HEXSIZE + 1];
+	size_t i;
+	int filebuf_hash, error = 0;
+
+	GIT_ASSERT_ARG(repo);
+
+	filebuf_hash = git_filebuf_hash_flags(git_oid_algorithm(repo->oid_type));
+	GIT_ASSERT(filebuf_hash);
+
+	if ((error = git_str_joinpath(&path, repo->gitdir, "shallow")) < 0)
+		goto on_error;
+
+	if ((error = git_filebuf_open(&file, git_str_cstr(&path), filebuf_hash, 0666)) < 0)
+		goto on_error;
+
+	for (i = 0; i < roots->count; i++) {
+		git_oid_tostr(oid_str, sizeof(oid_str), &roots->ids[i]);
+		git_filebuf_write(&file, oid_str, git_oid_hexsize(repo->oid_type));
+		git_filebuf_write(&file, "\n", 1);
+	}
+
+	git_filebuf_commit(&file);
+
+	if ((error = load_grafts(repo)) < 0) {
+		error = -1;
+		goto on_error;
+	}
+
+	if (!roots->count)
+		remove(path.ptr);
+
+on_error:
+	git_str_dispose(&path);
+
+	return error;
+}
+
 int git_repository_is_shallow(git_repository *repo)
 {
 	git_str path = GIT_STR_INIT;
@@ -3647,6 +3750,7 @@ int git_repository_is_shallow(git_repository *repo)
 
 	if (error < 0)
 		return error;
+
 	return st.st_size == 0 ? 0 : 1;
 }
 

src/libgit2/repository.h

@@ -24,6 +24,7 @@
 #include "attrcache.h"
 #include "submodule.h"
 #include "diff_driver.h"
+#include "grafts.h"
 
 #define DOT_GIT ".git"
 #define GIT_DIR DOT_GIT "/"
@@ -158,6 +159,9 @@ struct git_repository {
 
 	unsigned int lru_counter;
 
+	git_grafts *grafts;
+	git_grafts *shallow_grafts;
+
 	git_atomic32 attr_session_key;
 
 	intptr_t configmap_cache[GIT_CONFIGMAP_CACHE_MAX];
@@ -189,6 +193,8 @@ int git_repository_config__weakptr(git_config **out, git_repository *repo);
 int git_repository_odb__weakptr(git_odb **out, git_repository *repo);
 int git_repository_refdb__weakptr(git_refdb **out, git_repository *repo);
 int git_repository_index__weakptr(git_index **out, git_repository *repo);
+int git_repository_grafts__weakptr(git_grafts **out, git_repository *repo);
+int git_repository_shallow_grafts__weakptr(git_grafts **out, git_repository *repo);
 
 int git_repository__wrap_odb(
 	git_repository **out,
@@ -245,6 +251,9 @@ extern size_t git_repository__reserved_names_posix_len;
 bool git_repository__reserved_names(
 	git_str **out, size_t *outlen, git_repository *repo, bool include_ntfs);
 
+int git_repository__shallow_roots(git_oid **out, size_t *out_len, git_repository *repo);
+int git_repository__shallow_roots_write(git_repository *repo, git_oidarray *roots);
+
 /*
  * The default branch for the repository; the `init.defaultBranch`
  * configuration option, if set, or `master` if it is not.

src/libgit2/transports/local.c

@@ -295,15 +295,13 @@ static int local_ls(const git_remote_head ***out, size_t *size, git_transport *t
 static int local_negotiate_fetch(
 	git_transport *transport,
 	git_repository *repo,
-	const git_remote_head * const *refs,
-	size_t count)
+	const git_fetch_negotiation *wants)
 {
 	transport_local *t = (transport_local*)transport;
 	git_remote_head *rhead;
 	unsigned int i;
 
-	GIT_UNUSED(refs);
-	GIT_UNUSED(count);
+	GIT_UNUSED(wants);
 
 	/* Fill in the loids */
 	git_vector_foreach(&t->refs, i, rhead) {
@@ -322,6 +320,16 @@ static int local_negotiate_fetch(
 	return 0;
 }
 
+static int local_shallow_roots(
+	git_oidarray *out,
+	git_transport *transport)
+{
+	GIT_UNUSED(out);
+	GIT_UNUSED(transport);
+
+	return 0;
+}
+
 static int local_push_update_remote_ref(
 	git_repository *remote_repo,
 	const char *lref,
@@ -747,6 +755,7 @@ int git_transport_local(git_transport **out, git_remote *owner, void *param)
 	t->parent.oid_type = local_oid_type;
 #endif
 	t->parent.negotiate_fetch = local_negotiate_fetch;
+	t->parent.shallow_roots = local_shallow_roots;
 	t->parent.download_pack = local_download_pack;
 	t->parent.push = local_push;
 	t->parent.close = local_close;

src/libgit2/transports/smart.c

@@ -416,6 +416,8 @@ static void git_smart__free(git_transport *transport)
 
 	git_remote_connect_options_dispose(&t->connect_opts);
 
+	git_array_dispose(t->shallow_roots);
+
 	git__free(t->caps.object_format);
 	git__free(t->caps.agent);
 	git__free(t);
@@ -490,6 +492,7 @@ int git_transport_smart(git_transport **out, git_remote *owner, void *param)
 	t->parent.close = git_smart__close;
 	t->parent.free = git_smart__free;
 	t->parent.negotiate_fetch = git_smart__negotiate_fetch;
+	t->parent.shallow_roots = git_smart__shallow_roots;
 	t->parent.download_pack = git_smart__download_pack;
 	t->parent.push = git_smart__push;
 	t->parent.ls = git_smart__ls;

src/libgit2/transports/smart.h

@@ -14,6 +14,7 @@
 #include "netops.h"
 #include "push.h"
 #include "str.h"
+#include "oidarray.h"
 #include "git2/sys/transport.h"
 
 #define GIT_SIDE_BAND_DATA     1
@@ -32,6 +33,7 @@
 #define GIT_CAP_SYMREF "symref"
 #define GIT_CAP_WANT_TIP_SHA1 "allow-tip-sha1-in-want"
 #define GIT_CAP_WANT_REACHABLE_SHA1 "allow-reachable-sha1-in-want"
+#define GIT_CAP_SHALLOW "shallow"
 #define GIT_CAP_OBJECT_FORMAT "object-format="
 #define GIT_CAP_AGENT "agent="
 
@@ -50,7 +52,9 @@ typedef enum {
 	GIT_PKT_PROGRESS,
 	GIT_PKT_OK,
 	GIT_PKT_NG,
-	GIT_PKT_UNPACK
+	GIT_PKT_UNPACK,
+	GIT_PKT_SHALLOW,
+	GIT_PKT_UNSHALLOW
 } git_pkt_type;
 
 /* Used for multi_ack and multi_ack_detailed */
@@ -122,6 +126,11 @@ typedef struct {
 	int unpack_ok;
 } git_pkt_unpack;
 
+typedef struct {
+	git_pkt_type type;
+	git_oid oid;
+} git_pkt_shallow;
+
 typedef struct transport_smart_caps {
 	unsigned int common:1,
 	             ofs_delta:1,
@@ -134,7 +143,8 @@ typedef struct transport_smart_caps {
 	             report_status:1,
 	             thin_pack:1,
 	             want_tip_sha1:1,
-	             want_reachable_sha1:1;
+	             want_reachable_sha1:1,
+	             shallow:1;
 	char *object_format;
 	char *agent;
 } transport_smart_caps;
@@ -153,6 +163,7 @@ typedef struct {
 	git_vector refs;
 	git_vector heads;
 	git_vector common;
+	git_array_oid_t shallow_roots;
 	git_atomic32 cancelled;
 	packetsize_cb packetsize_cb;
 	void *packetsize_payload;
@@ -171,8 +182,9 @@ int git_smart__push(git_transport *transport, git_push *push);
 int git_smart__negotiate_fetch(
 	git_transport *transport,
 	git_repository *repo,
-	const git_remote_head * const *refs,
-	size_t count);
+	const git_fetch_negotiation *wants);
+
+int git_smart__shallow_roots(git_oidarray *out, git_transport *transport);
 
 int git_smart__download_pack(
 	git_transport *transport,
@@ -195,7 +207,7 @@ int git_pkt_parse_line(git_pkt **head, const char **endptr, const char *line, si
 int git_pkt_buffer_flush(git_str *buf);
 int git_pkt_send_flush(GIT_SOCKET s);
 int git_pkt_buffer_done(git_str *buf);
-int git_pkt_buffer_wants(const git_remote_head * const *refs, size_t count, transport_smart_caps *caps, git_str *buf);
+int git_pkt_buffer_wants(const git_fetch_negotiation *wants, transport_smart_caps *caps, git_str *buf);
 int git_pkt_buffer_have(git_oid *oid, git_str *buf);
 void git_pkt_free(git_pkt *pkt);
 

src/libgit2/transports/smart_pkt.c

@@ -44,9 +44,16 @@ static int flush_pkt(git_pkt **out)
 }
 
 /* the rest of the line will be useful for multi_ack and multi_ack_detailed */
-static int ack_pkt(git_pkt **out, const char *line, size_t len)
+static int ack_pkt(
+	git_pkt **out,
+	const char *line,
+	size_t len,
+	git_pkt_parse_data *data)
 {
 	git_pkt_ack *pkt;
+	size_t oid_hexsize = git_oid_hexsize(data->oid_type);
+
+	GIT_ASSERT(data && data->oid_type);
 
 	pkt = git__calloc(1, sizeof(git_pkt_ack));
 	GIT_ERROR_CHECK_ALLOC(pkt);
@@ -57,11 +64,11 @@ static int ack_pkt(git_pkt **out, const char *line, size_t len)
 	line += 4;
 	len -= 4;
 
-	if (len < GIT_OID_SHA1_HEXSIZE ||
-	    git_oid__fromstr(&pkt->oid, line, GIT_OID_SHA1) < 0)
+	if (len < oid_hexsize ||
+	    git_oid__fromstr(&pkt->oid, line, data->oid_type) < 0)
 		goto out_err;
-	line += GIT_OID_SHA1_HEXSIZE;
-	len -= GIT_OID_SHA1_HEXSIZE;
+	line += oid_hexsize;
+	len -= oid_hexsize;
 
 	if (len && line[0] == ' ') {
 		line++;
@@ -436,6 +443,84 @@ static int unpack_pkt(git_pkt **out, const char *line, size_t len)
 	return 0;
 }
 
+static int shallow_pkt(
+	git_pkt **out,
+	const char *line,
+	size_t len,
+	git_pkt_parse_data *data)
+{
+	git_pkt_shallow *pkt;
+	size_t oid_hexsize = git_oid_hexsize(data->oid_type);
+
+	GIT_ASSERT(data && data->oid_type);
+
+	pkt = git__calloc(1, sizeof(git_pkt_shallow));
+	GIT_ERROR_CHECK_ALLOC(pkt);
+
+	pkt->type = GIT_PKT_SHALLOW;
+
+	if (git__prefixncmp(line, len, "shallow "))
+		goto out_err;
+
+	line += 8;
+	len -= 8;
+
+	if (len != oid_hexsize)
+		goto out_err;
+
+	git_oid__fromstr(&pkt->oid, line, data->oid_type);
+	line += oid_hexsize + 1;
+	len -= oid_hexsize + 1;
+
+	*out = (git_pkt *)pkt;
+
+	return 0;
+
+out_err:
+	git_error_set(GIT_ERROR_NET, "invalid packet line");
+	git__free(pkt);
+	return -1;
+}
+
+static int unshallow_pkt(
+	git_pkt **out,
+	const char *line,
+	size_t len,
+	git_pkt_parse_data *data)
+{
+	git_pkt_shallow *pkt;
+	size_t oid_hexsize = git_oid_hexsize(data->oid_type);
+
+	GIT_ASSERT(data && data->oid_type);
+
+	pkt = git__calloc(1, sizeof(git_pkt_shallow));
+	GIT_ERROR_CHECK_ALLOC(pkt);
+
+	pkt->type = GIT_PKT_UNSHALLOW;
+
+	if (git__prefixncmp(line, len, "unshallow "))
+		goto out_err;
+
+	line += 10;
+	len -= 10;
+
+	if (len != oid_hexsize)
+		goto out_err;
+
+	git_oid__fromstr(&pkt->oid, line, data->oid_type);
+	line += oid_hexsize + 1;
+	len -= oid_hexsize + 1;
+
+	*out = (git_pkt *) pkt;
+
+	return 0;
+
+out_err:
+	git_error_set(GIT_ERROR_NET, "invalid packet line");
+	git__free(pkt);
+	return -1;
+}
+
 static int parse_len(size_t *out, const char *line, size_t linelen)
 {
 	char num[PKT_LEN_SIZE + 1];
@@ -553,7 +638,7 @@ int git_pkt_parse_line(
 	else if (*line == GIT_SIDE_BAND_ERROR)
 		error = sideband_error_pkt(pkt, line, len);
 	else if (!git__prefixncmp(line, len, "ACK"))
-		error = ack_pkt(pkt, line, len);
+		error = ack_pkt(pkt, line, len, data);
 	else if (!git__prefixncmp(line, len, "NAK"))
 		error = nak_pkt(pkt);
 	else if (!git__prefixncmp(line, len, "ERR"))
@@ -566,6 +651,10 @@ int git_pkt_parse_line(
 		error = ng_pkt(pkt, line, len);
 	else if (!git__prefixncmp(line, len, "unpack"))
 		error = unpack_pkt(pkt, line, len);
+	else if (!git__prefixcmp(line, "shallow"))
+		error = shallow_pkt(pkt, line, len, data);
+	else if (!git__prefixcmp(line, "unshallow"))
+		error = unshallow_pkt(pkt, line, len, data);
 	else
 		error = ref_pkt(pkt, line, len, data);
 
@@ -638,6 +727,9 @@ static int buffer_want_with_caps(
 	if (caps->ofs_delta)
 		git_str_puts(&str, GIT_CAP_OFS_DELTA " ");
 
+	if (caps->shallow)
+		git_str_puts(&str, GIT_CAP_SHALLOW " ");
+
 	if (git_str_oom(&str))
 		return -1;
 
@@ -668,8 +760,7 @@ static int buffer_want_with_caps(
  */
 
 int git_pkt_buffer_wants(
-	const git_remote_head * const *refs,
-	size_t count,
+	const git_fetch_negotiation *wants,
 	transport_smart_caps *caps,
 	git_str *buf)
 {
@@ -679,7 +770,7 @@ int git_pkt_buffer_wants(
 	size_t oid_hexsize, want_len, i = 0;
 
 #ifdef GIT_EXPERIMENTAL_SHA256
-	oid_type = count > 0 ? refs[0]->oid.type : GIT_OID_SHA1;
+	oid_type = wants->refs_len > 0 ? wants->refs[0]->oid.type : GIT_OID_SHA1;
 #else
 	oid_type = GIT_OID_SHA1;
 #endif
@@ -690,20 +781,20 @@ int git_pkt_buffer_wants(
 	      oid_hexsize + 1 /* LF */;
 
 	if (caps->common) {
-		for (; i < count; ++i) {
-			head = refs[i];
+		for (; i < wants->refs_len; ++i) {
+			head = wants->refs[i];
 			if (!head->local)
 				break;
 		}
 
-		if (buffer_want_with_caps(refs[i], caps, oid_type, buf) < 0)
+		if (buffer_want_with_caps(wants->refs[i], caps, oid_type, buf) < 0)
 			return -1;
 
 		i++;
 	}
 
-	for (; i < count; ++i) {
-		head = refs[i];
+	for (; i < wants->refs_len; ++i) {
+		head = wants->refs[i];
 
 		if (head->local)
 			continue;
@@ -718,6 +809,36 @@ int git_pkt_buffer_wants(
 			return -1;
 	}
 
+	/* Tell the server about our shallow objects */
+	for (i = 0; i < wants->shallow_roots_len; i++) {
+		char oid[GIT_OID_MAX_HEXSIZE + 1];
+		git_str shallow_buf = GIT_STR_INIT;
+
+		git_oid_tostr(oid, GIT_OID_MAX_HEXSIZE + 1, &wants->shallow_roots[i]);
+		git_str_puts(&shallow_buf, "shallow ");
+		git_str_puts(&shallow_buf, oid);
+		git_str_putc(&shallow_buf, '\n');
+
+		git_str_printf(buf, "%04x%s", (unsigned int)git_str_len(&shallow_buf) + 4, git_str_cstr(&shallow_buf));
+
+		git_str_dispose(&shallow_buf);
+
+		if (git_str_oom(buf))
+			return -1;
+	}
+
+	if (wants->depth > 0) {
+		git_str deepen_buf = GIT_STR_INIT;
+
+		git_str_printf(&deepen_buf, "deepen %d\n", wants->depth);
+		git_str_printf(buf,"%04x%s", (unsigned int)git_str_len(&deepen_buf) + 4, git_str_cstr(&deepen_buf));
+
+		git_str_dispose(&deepen_buf);
+
+		if (git_str_oom(buf))
+			return -1;
+	}
+
 	return git_pkt_buffer_flush(buf);
 }
 

src/libgit2/transports/smart_protocol.c

@@ -243,6 +243,12 @@ int git_smart__detect_caps(
 			continue;
 		}
 
+		if (!git__prefixcmp(ptr, GIT_CAP_SHALLOW)) {
+			caps->common = caps->shallow = 1;
+			ptr += strlen(GIT_CAP_SHALLOW);
+			continue;
+		}
+
 		/* We don't know this capability, so skip it */
 		ptr = strchr(ptr, ' ');
 	}
@@ -250,13 +256,20 @@ int git_smart__detect_caps(
 	return 0;
 }
 
-static int recv_pkt(git_pkt **out_pkt, git_pkt_type *out_type, gitno_buffer *buf)
+static int recv_pkt(
+	git_pkt **out_pkt,
+	git_pkt_type *out_type,
+	transport_smart *t,
+	gitno_buffer *buf)
 {
 	const char *ptr = buf->data, *line_end = ptr;
 	git_pkt *pkt = NULL;
 	git_pkt_parse_data pkt_parse_data = { 0 };
 	int error = 0, ret;
 
+	pkt_parse_data.oid_type = t->owner->repo->oid_type;
+	pkt_parse_data.seen_capabilities = 1;
+
 	do {
 		if (buf->offset > 0)
 			error = git_pkt_parse_line(&pkt, &line_end, ptr, buf->offset, &pkt_parse_data);
@@ -297,7 +310,7 @@ static int store_common(transport_smart *t)
 	int error;
 
 	do {
-		if ((error = recv_pkt(&pkt, NULL, buf)) < 0)
+		if ((error = recv_pkt(&pkt, NULL, t, buf)) < 0)
 			return error;
 
 		if (pkt->type != GIT_PKT_ACK) {
@@ -314,7 +327,7 @@ static int store_common(transport_smart *t)
 	return 0;
 }
 
-static int wait_while_ack(gitno_buffer *buf)
+static int wait_while_ack(transport_smart *t, gitno_buffer *buf)
 {
 	int error;
 	git_pkt *pkt = NULL;
@@ -323,7 +336,7 @@ static int wait_while_ack(gitno_buffer *buf)
 	while (1) {
 		git_pkt_free(pkt);
 
-		if ((error = recv_pkt(&pkt, NULL, buf)) < 0)
+		if ((error = recv_pkt(&pkt, NULL, t, buf)) < 0)
 			return error;
 
 		if (pkt->type == GIT_PKT_NAK)
@@ -344,7 +357,48 @@ static int wait_while_ack(gitno_buffer *buf)
 	return 0;
 }
 
-int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, const git_remote_head * const *wants, size_t count)
+static int cap_not_sup_err(const char *cap_name)
+{
+	git_error_set(GIT_ERROR_NET, "server doesn't support %s", cap_name);
+	return GIT_EINVALID;
+}
+
+/* Disables server capabilities we're not interested in */
+static int setup_caps(
+	transport_smart_caps *caps,
+	const git_fetch_negotiation *wants)
+{
+	if (wants->depth > 0) {
+		if (!caps->shallow)
+			return cap_not_sup_err(GIT_CAP_SHALLOW);
+	} else {
+		caps->shallow = 0;
+	}
+
+	return 0;
+}
+
+static int setup_shallow_roots(
+	git_array_oid_t *out,
+	const git_fetch_negotiation *wants)
+{
+	git_array_clear(*out);
+
+	if (wants->shallow_roots_len > 0) {
+		git_array_init_to_size(*out, wants->shallow_roots_len);
+		GIT_ERROR_CHECK_ALLOC(out->ptr);
+
+		memcpy(out->ptr, wants->shallow_roots,
+		       sizeof(git_oid) * wants->shallow_roots_len);
+	}
+
+	return 0;
+}
+
+int git_smart__negotiate_fetch(
+	git_transport *transport,
+	git_repository *repo,
+	const git_fetch_negotiation *wants)
 {
 	transport_smart *t = (transport_smart *)transport;
 	git_revwalk__push_options opts = GIT_REVWALK__PUSH_OPTIONS_INIT;
@@ -356,7 +410,11 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 	unsigned int i;
 	git_oid oid;
 
-	if ((error = git_pkt_buffer_wants(wants, count, &t->caps, &data)) < 0)
+	if ((error = setup_caps(&t->caps, wants)) < 0 ||
+	    (error = setup_shallow_roots(&t->shallow_roots, wants)) < 0)
+		return error;
+
+	if ((error = git_pkt_buffer_wants(wants, &t->caps, &data)) < 0)
 		return error;
 
 	if ((error = git_revwalk_new(&walk, repo)) < 0)
@@ -366,6 +424,37 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 	if ((error = git_revwalk__push_glob(walk, "refs/*", &opts)) < 0)
 		goto on_error;
 
+	if (wants->depth > 0) {
+		git_pkt_shallow *pkt;
+
+		if ((error = git_smart__negotiation_step(&t->parent, data.ptr, data.size)) < 0)
+			goto on_error;
+
+		while ((error = recv_pkt((git_pkt **)&pkt, NULL, t, buf)) == 0) {
+			bool complete = false;
+
+			if (pkt->type == GIT_PKT_SHALLOW) {
+				error = git_oidarray__add(&t->shallow_roots, &pkt->oid);
+			} else if (pkt->type == GIT_PKT_UNSHALLOW) {
+				git_oidarray__remove(&t->shallow_roots, &pkt->oid);
+			} else if (pkt->type == GIT_PKT_FLUSH) {
+				/* Server is done, stop processing shallow oids */
+				complete = true;
+			} else {
+				git_error_set(GIT_ERROR_NET, "unexpected packet type");
+				error = -1;
+			}
+
+			git_pkt_free((git_pkt *) pkt);
+
+			if (complete || error < 0)
+				break;
+		}
+
+		if (error < 0)
+			goto on_error;
+	}
+
 	/*
 	 * Our support for ACK extensions is simply to parse them. On
 	 * the first ACK we will accept that as enough common
@@ -406,7 +495,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 				if ((error = store_common(t)) < 0)
 					goto on_error;
 			} else {
-				if ((error = recv_pkt(NULL, &pkt_type, buf)) < 0)
+				if ((error = recv_pkt(NULL, &pkt_type, t, buf)) < 0)
 					goto on_error;
 
 				if (pkt_type == GIT_PKT_ACK) {
@@ -428,7 +517,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 			git_pkt_ack *pkt;
 			unsigned int j;
 
-			if ((error = git_pkt_buffer_wants(wants, count, &t->caps, &data)) < 0)
+			if ((error = git_pkt_buffer_wants(wants, &t->caps, &data)) < 0)
 				goto on_error;
 
 			git_vector_foreach(&t->common, j, pkt) {
@@ -448,7 +537,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 		git_pkt_ack *pkt;
 		unsigned int j;
 
-		if ((error = git_pkt_buffer_wants(wants, count, &t->caps, &data)) < 0)
+		if ((error = git_pkt_buffer_wants(wants, &t->caps, &data)) < 0)
 			goto on_error;
 
 		git_vector_foreach(&t->common, j, pkt) {
@@ -466,10 +555,11 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 		goto on_error;
 
 	if (t->cancelled.val) {
-		git_error_set(GIT_ERROR_NET, "The fetch was cancelled by the user");
+		git_error_set(GIT_ERROR_NET, "the fetch was cancelled");
 		error = GIT_EUSER;
 		goto on_error;
 	}
+
 	if ((error = git_smart__negotiation_step(&t->parent, data.ptr, data.size)) < 0)
 		goto on_error;
 
@@ -478,7 +568,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 
 	/* Now let's eat up whatever the server gives us */
 	if (!t->caps.multi_ack && !t->caps.multi_ack_detailed) {
-		if ((error = recv_pkt(NULL, &pkt_type, buf)) < 0)
+		if ((error = recv_pkt(NULL, &pkt_type, t, buf)) < 0)
 			return error;
 
 		if (pkt_type != GIT_PKT_ACK && pkt_type != GIT_PKT_NAK) {
@@ -486,7 +576,7 @@ int git_smart__negotiate_fetch(git_transport *transport, git_repository *repo, c
 			return -1;
 		}
 	} else {
-		error = wait_while_ack(buf);
+		error = wait_while_ack(t, buf);
 	}
 
 	return error;
@@ -497,6 +587,25 @@ on_error:
 	return error;
 }
 
+int git_smart__shallow_roots(git_oidarray *out, git_transport *transport)
+{
+	transport_smart *t = (transport_smart *)transport;
+	size_t len;
+
+	GIT_ERROR_CHECK_ALLOC_MULTIPLY(&len, t->shallow_roots.size, sizeof(git_oid));
+
+	out->count = t->shallow_roots.size;
+
+	if (len) {
+		out->ids = git__malloc(len);
+		memcpy(out->ids, t->shallow_roots.ptr, len);
+	} else {
+		out->ids = NULL;
+	}
+
+	return 0;
+}
+
 static int no_sideband(transport_smart *t, struct git_odb_writepack *writepack, gitno_buffer *buf, git_indexer_progress *stats)
 {
 	int recvd;
@@ -602,7 +711,7 @@ int git_smart__download_pack(
 			goto done;
 		}
 
-		if ((error = recv_pkt(&pkt, NULL, buf)) >= 0) {
+		if ((error = recv_pkt(&pkt, NULL, t, buf)) >= 0) {
 			/* Check cancellation after network call */
 			if (t->cancelled.val) {
 				git_error_clear();

src/util/array.h

@@ -33,6 +33,9 @@
 #define git_array_init_to_size(a, desired) \
 	do { (a).size = 0; (a).asize = desired; (a).ptr = git__calloc(desired, sizeof(*(a).ptr)); } while (0)
 
+#define git_array_dispose(a) \
+	do { git__free((a).ptr); } while (0)
+
 #define git_array_clear(a) \
 	do { git__free((a).ptr); git_array_init(a); } while (0)
 
@@ -85,12 +88,14 @@ on_oom:
 #define git_array_foreach(a, i, element) \
 	for ((i) = 0; (i) < (a).size && ((element) = &(a).ptr[(i)]); (i)++)
 
+typedef int (*git_array_compare_cb)(const void *, const void *);
+
 GIT_INLINE(int) git_array__search(
 	size_t *out,
 	void *array_ptr,
 	size_t item_size,
 	size_t array_len,
-	int (*compare)(const void *, const void *),
+	git_array_compare_cb compare,
 	const void *key)
 {
 	size_t lim;

src/util/futils.c

@@ -221,14 +221,14 @@ int git_futils_readbuffer_fd_full(git_str *buf, git_file fd)
 int git_futils_readbuffer_updated(
 	git_str *out,
 	const char *path,
-	unsigned char checksum[GIT_HASH_SHA1_SIZE],
+	unsigned char checksum[GIT_HASH_SHA256_SIZE],
 	int *updated)
 {
 	int error;
 	git_file fd;
 	struct stat st;
 	git_str buf = GIT_STR_INIT;
-	unsigned char checksum_new[GIT_HASH_SHA1_SIZE];
+	unsigned char checksum_new[GIT_HASH_SHA256_SIZE];
 
 	GIT_ASSERT_ARG(out);
 	GIT_ASSERT_ARG(path && *path);
@@ -261,7 +261,10 @@ int git_futils_readbuffer_updated(
 	p_close(fd);
 
 	if (checksum) {
-		if ((error = git_hash_buf(checksum_new, buf.ptr, buf.size, GIT_HASH_ALGORITHM_SHA1)) < 0) {
+		error = git_hash_buf(checksum_new, buf.ptr,
+		                     buf.size, GIT_HASH_ALGORITHM_SHA256);
+
+		if (error < 0) {
 			git_str_dispose(&buf);
 			return error;
 		}
@@ -269,7 +272,7 @@ int git_futils_readbuffer_updated(
 		/*
 		 * If we were given a checksum, we only want to use it if it's different
 		 */
-		if (!memcmp(checksum, checksum_new, GIT_HASH_SHA1_SIZE)) {
+		if (!memcmp(checksum, checksum_new, GIT_HASH_SHA256_SIZE)) {
 			git_str_dispose(&buf);
 			if (updated)
 				*updated = 0;
@@ -277,7 +280,7 @@ int git_futils_readbuffer_updated(
 			return 0;
 		}
 
-		memcpy(checksum, checksum_new, GIT_HASH_SHA1_SIZE);
+		memcpy(checksum, checksum_new, GIT_HASH_SHA256_SIZE);
 	}
 
 	/*

tests/libgit2/core/oidarray.c

+#include "clar_libgit2.h"
+
+#include "git2/oid.h"
+#include "git2/transport.h"
+
+#include "common.h"
+#include "transports/smart.h"
+#include "oid.h"
+#include "oidarray.h"
+
+#include <assert.h>
+
+#define oid_0 "c070ad8c08840c8116da865b2d65593a6bb9cd2a"
+#define oid_1 "0966a434eb1a025db6b71485ab63a3bfbea520b6"
+#define oid_2 "83834a7afdaa1a1260568567f6ad90020389f664"
+#define oid_3 "746fb4c91a7b6190bc4761adf7410afc4b59812c"
+
+void test_core_oidarray__add_and_remove_oid_from_shallowarray(void)
+{
+	git_oid oid_0_obj, oid_1_obj, oid_2_obj, oid_3_obj;
+	git_array_oid_t array = GIT_ARRAY_INIT;
+
+	git_oid__fromstr(&oid_0_obj, oid_0, GIT_OID_SHA1);
+	git_oid__fromstr(&oid_1_obj, oid_1, GIT_OID_SHA1);
+	git_oid__fromstr(&oid_2_obj, oid_2, GIT_OID_SHA1);
+	git_oid__fromstr(&oid_3_obj, oid_3, GIT_OID_SHA1);
+
+	/* add some initial ids */
+	git_oidarray__add(&array, &oid_0_obj);
+	git_oidarray__add(&array, &oid_1_obj);
+	git_oidarray__add(&array, &oid_2_obj);
+
+	cl_assert_equal_i(3, array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[1]));
+	cl_assert_equal_s("83834a7afdaa1a1260568567f6ad90020389f664", git_oid_tostr_s(&array.ptr[2]));
+
+	/* don't duplicate existing ids */
+	git_oidarray__add(&array, &oid_1_obj);
+
+	cl_assert_equal_i(3, array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[1]));
+	cl_assert_equal_s("83834a7afdaa1a1260568567f6ad90020389f664", git_oid_tostr_s(&array.ptr[2]));
+
+	/* remove the last id */
+	cl_assert_equal_i(1, git_oidarray__remove(&array, &oid_2_obj));
+
+	cl_assert_equal_i(2, array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[1]));
+
+	/* add another id */
+	git_oidarray__add(&array, &oid_3_obj);
+
+	cl_assert_equal_i(3, array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[1]));
+	cl_assert_equal_s("746fb4c91a7b6190bc4761adf7410afc4b59812c", git_oid_tostr_s(&array.ptr[2]));
+
+	/* remove the first id */
+	cl_assert_equal_i(1, git_oidarray__remove(&array, &oid_0_obj));
+
+	cl_assert_equal_i(2, array.size);
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("746fb4c91a7b6190bc4761adf7410afc4b59812c", git_oid_tostr_s(&array.ptr[1]));
+
+	/* removing a nonexistent oid does nothing */
+	cl_assert_equal_i(0, git_oidarray__remove(&array, &oid_2_obj));
+
+	/* add another id */
+	git_oidarray__add(&array, &oid_0_obj);
+
+	cl_assert_equal_i(3, array.size);
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("746fb4c91a7b6190bc4761adf7410afc4b59812c", git_oid_tostr_s(&array.ptr[1]));
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[2]));
+
+	/* remove another id */
+	cl_assert_equal_i(1, git_oidarray__remove(&array, &oid_3_obj));
+
+	cl_assert_equal_i(2, array.size);
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&array.ptr[0]));
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[1]));
+
+	/* remove another id */
+	cl_assert_equal_i(1, git_oidarray__remove(&array, &oid_1_obj));
+
+	cl_assert_equal_i(1, array.size);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&array.ptr[0]));
+
+	/* remove the final id */
+	cl_assert_equal_i(1, git_oidarray__remove(&array, &oid_0_obj));
+
+	cl_assert_equal_i(0, array.size);
+
+	git_array_clear(array);
+}

tests/libgit2/grafts/basic.c

+#include "clar_libgit2.h"
+
+#include "futils.h"
+#include "grafts.h"
+
+static git_repository *g_repo;
+
+void test_grafts_basic__initialize(void)
+{
+	g_repo = cl_git_sandbox_init("grafted.git");
+}
+
+void test_grafts_basic__cleanup(void)
+{
+	cl_git_sandbox_cleanup();
+}
+
+void test_grafts_basic__graft_add(void)
+{
+	git_array_oid_t parents = GIT_ARRAY_INIT;
+	git_oid oid_src, *oid1;
+	git_commit_graft *graft;
+	git_grafts *grafts;
+
+	cl_git_pass(git_grafts_new(&grafts, GIT_OID_SHA1));
+
+	cl_assert(oid1 = git_array_alloc(parents));
+	cl_git_pass(git_oid__fromstr(&oid_src, "2f3053cbff8a4ca2f0666de364ddb734a28a31a9", GIT_OID_SHA1));
+	git_oid_cpy(oid1, &oid_src);
+
+	git_oid__fromstr(&oid_src, "f503807ffa920e407a600cfaee96b7152259acc7", GIT_OID_SHA1);
+	cl_git_pass(git_grafts_add(grafts, &oid_src, parents));
+	git_array_clear(parents);
+
+	cl_assert_equal_i(1, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &oid_src));
+	cl_assert_equal_s("f503807ffa920e407a600cfaee96b7152259acc7", git_oid_tostr_s(&graft->oid));
+	cl_assert_equal_i(1, git_array_size(graft->parents));
+	cl_assert_equal_s("2f3053cbff8a4ca2f0666de364ddb734a28a31a9", git_oid_tostr_s(git_array_get(graft->parents, 0)));
+
+	git_grafts_free(grafts);
+}
+
+void test_grafts_basic__grafted_revwalk(void)
+{
+	git_revwalk *w;
+	git_oid oids[10];
+	size_t i = 0;
+	git_commit *commit;
+
+	cl_git_pass(git_revwalk_new(&w, g_repo));
+	cl_git_pass(git_revwalk_push_ref(w, "refs/heads/branch"));
+
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[0]), "8a00e91619098618be97c0d2ceabb05a2c58edd9");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[1]), "f503807ffa920e407a600cfaee96b7152259acc7");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[2]), "2f3053cbff8a4ca2f0666de364ddb734a28a31a9");
+
+	cl_git_fail_with(GIT_ITEROVER, git_revwalk_next(&oids[i++], w));
+
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oids[0]));
+
+	cl_assert_equal_i(1, git_commit_parentcount(commit));
+
+	git_commit_free(commit);
+	git_revwalk_free(w);
+}
+
+void test_grafts_basic__grafted_objects(void)
+{
+	git_oid oid;
+	git_commit *commit;
+
+	cl_git_pass(git_oid__fromstr(&oid, "f503807ffa920e407a600cfaee96b7152259acc7", GIT_OID_SHA1));
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oid));
+	cl_assert_equal_i(1, git_commit_parentcount(commit));
+	git_commit_free(commit);
+
+	cl_git_pass(git_oid__fromstr(&oid, "0512adebd3782157f0d5c9b22b043f87b4aaff9e", GIT_OID_SHA1));
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oid));
+	cl_assert_equal_i(1, git_commit_parentcount(commit));
+	git_commit_free(commit);
+
+	cl_git_pass(git_oid__fromstr(&oid, "66cc22a015f6ca75b34c82d28f78ba663876bade", GIT_OID_SHA1));
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &oid));
+	cl_assert_equal_i(4, git_commit_parentcount(commit));
+	git_commit_free(commit);
+}
+
+void test_grafts_basic__grafted_merge_revwalk(void)
+{
+	git_revwalk *w;
+	git_oid oids[10];
+	size_t i = 0;
+
+	cl_git_pass(git_revwalk_new(&w, g_repo));
+	cl_git_pass(git_revwalk_push_ref(w, "refs/heads/bottom"));
+
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "66cc22a015f6ca75b34c82d28f78ba663876bade");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "e414f42f4e6bc6934563a2349a8600f0ab68618e");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "8a00e91619098618be97c0d2ceabb05a2c58edd9");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "1c18e80a276611bb9b146590616bbc5aebdf2945");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "d7224d49d6d5aff6ade596ed74f4bcd4f77b29e2");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "0512adebd3782157f0d5c9b22b043f87b4aaff9e");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "f503807ffa920e407a600cfaee96b7152259acc7");
+	cl_git_pass(git_revwalk_next(&oids[i++], w));
+	cl_assert_equal_s(git_oid_tostr_s(&oids[i - 1]), "2f3053cbff8a4ca2f0666de364ddb734a28a31a9");
+
+	cl_git_fail_with(GIT_ITEROVER, git_revwalk_next(&oids[i++], w));
+
+	git_revwalk_free(w);
+}

tests/libgit2/grafts/parse.c

+#include "clar_libgit2.h"
+
+#include "grafts.h"
+
+#define OID0 "c0368f9f9743e950e6cfe1f45a649f8a9dfcd97e"
+#define OID1 "cfc50a0db87ce908fb8a8c5b8f7b4ab96eee8643"
+#define OID2 "6914d97cd08b9edf5e855fca211c750fa82fd80a"
+#define OID3 "516521937d0e9ce9d0d836149a0702671f326b4a"
+#define OID4 "e2c29d67ef2f217650196f94c796f0532b8caad6"
+#define OID5 "79bcb936596cb50353fe7be28b7444e66e4a2842"
+#define OID6 "b9c54107d57c17dbcaf646c4d52f66eb9e69d23d"
+#define OID7 "9f8a746e9ad7b58cc840016bc3944d5ad262acb5"
+#define OID8 "392f4beef7d0d15b2bc5b1abe1a754eba0ec36da"
+
+#define OID_TRUNCATED "392f4beef7d0d15b2bc5b1abe1a754eba0ec36d"
+#define OID_NONHEX    "9f8a746e9ax7b58cc840016bc3944d5ad262acb5"
+
+static git_grafts *grafts;
+
+void test_grafts_parse__initialize(void)
+{
+	cl_git_pass(git_grafts_new(&grafts, GIT_OID_SHA1));
+}
+
+void test_grafts_parse__cleanup(void)
+{
+	git_grafts_free(grafts);
+	grafts = NULL;
+}
+
+static void assert_parse_succeeds(git_grafts *grafts, const char *string, size_t n)
+{
+	cl_git_pass(git_grafts_parse(grafts, string, strlen(string)));
+	cl_assert_equal_i(git_grafts_size(grafts), n);
+}
+
+static void assert_parse_fails(git_grafts *grafts, const char *string)
+{
+	cl_git_fail(git_grafts_parse(grafts, string, strlen(string)));
+}
+
+static void assert_graft_contains(git_grafts *grafts, const char *graft, size_t n, ...)
+{
+	git_commit_graft *commit;
+	git_oid oid;
+	va_list ap;
+	size_t i = 0;
+
+	cl_git_pass(git_oid__fromstr(&oid, graft, GIT_OID_SHA1));
+	cl_git_pass(git_grafts_get(&commit, grafts, &oid));
+	cl_assert_equal_oid(&commit->oid, &oid);
+	cl_assert_equal_i(commit->parents.size, n);
+
+	va_start(ap, n);
+	while (i < n) {
+		cl_git_pass(git_oid__fromstr(&oid, va_arg(ap, const char *), GIT_OID_SHA1));
+		cl_assert_equal_oid(&commit->parents.ptr[i], &oid);
+		i++;
+	}
+	va_end(ap);
+}
+
+void test_grafts_parse__single_oid(void)
+{
+	assert_parse_succeeds(grafts, OID1, 1);
+	assert_graft_contains(grafts, OID1, 0);
+}
+
+void test_grafts_parse__single_oid_with_newline(void)
+{
+	assert_parse_succeeds(grafts, OID1 "\n", 1);
+	assert_graft_contains(grafts, OID1, 0);
+}
+
+void test_grafts_parse__multiple_oids(void)
+{
+	assert_parse_succeeds(grafts, OID1 "\n" OID2 "\n" OID3, 3);
+	assert_graft_contains(grafts, OID1, 0);
+	assert_graft_contains(grafts, OID2, 0);
+	assert_graft_contains(grafts, OID3, 0);
+}
+
+void test_grafts_parse__same_oid(void)
+{
+	assert_parse_succeeds(grafts, OID1 "\n" OID1, 1);
+	assert_graft_contains(grafts, OID1, 0);
+}
+
+void test_grafts_parse__oid_with_parent(void)
+{
+	assert_parse_succeeds(grafts, OID1 " " OID2, 1);
+	assert_graft_contains(grafts, OID1, 1, OID2);
+}
+
+void test_grafts_parse__oid_with_parent_and_newline(void)
+{
+	assert_parse_succeeds(grafts, OID1 " " OID2 "\n", 1);
+	assert_graft_contains(grafts, OID1, 1, OID2);
+}
+
+void test_grafts_parse__oid_with_multiple_parents(void)
+{
+	assert_parse_succeeds(grafts, OID1 " " OID2 " " OID3 " " OID4 " " OID5, 1);
+	assert_graft_contains(grafts, OID1, 4, OID2, OID3, OID4, OID5);
+}
+
+void test_grafts_parse__multiple_oids_with_multiple_parents(void)
+{
+	assert_parse_succeeds(grafts,
+		OID1 " " OID2 " " OID3 " " OID4 " " OID5 "\n"
+		OID6 " " OID7 " " OID8 "\n" , 2);
+	assert_graft_contains(grafts, OID1, 4, OID2, OID3, OID4, OID5);
+	assert_graft_contains(grafts, OID6, 2, OID7, OID8);
+}
+
+void test_grafts_parse__multiple_spaces_fails(void)
+{
+	assert_parse_fails(grafts, OID1 "  " OID2);
+}
+
+void test_grafts_parse__trailing_space_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " " OID2 " ");
+}
+
+void test_grafts_parse__invalid_character_inbetween_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " x " OID2);
+}
+
+void test_grafts_parse__truncated_oid_fails(void)
+{
+	assert_parse_fails(grafts, OID_TRUNCATED);
+}
+
+void test_grafts_parse__truncated_parent_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " " OID_TRUNCATED);
+}
+
+void test_grafts_parse__invalid_oid_fails(void)
+{
+	assert_parse_fails(grafts, OID_NONHEX);
+}
+
+void test_grafts_parse__invalid_parent_fails(void)
+{
+	assert_parse_fails(grafts, OID1 " " OID_NONHEX);
+}

tests/libgit2/grafts/shallow.c

+#include "clar_libgit2.h"
+
+#include "futils.h"
+#include "grafts.h"
+#include "repository.h"
+
+static git_repository *g_repo;
+static git_oid g_shallow_oid;
+
+void test_grafts_shallow__initialize(void)
+{
+	cl_git_pass(git_oid__fromstr(&g_shallow_oid, "be3563ae3f795b2b4353bcce3a527ad0a4f7f644", GIT_OID_SHA1));
+}
+
+void test_grafts_shallow__cleanup(void)
+{
+	cl_git_sandbox_cleanup();
+}
+
+void test_grafts_shallow__no_shallow_file(void)
+{
+	g_repo = cl_git_sandbox_init("testrepo.git");
+	cl_assert_equal_i(0, git_repository_is_shallow(g_repo));
+}
+
+void test_grafts_shallow__empty_shallow_file(void)
+{
+	g_repo = cl_git_sandbox_init("testrepo.git");
+	cl_git_mkfile("testrepo.git/shallow", "");
+	cl_assert_equal_i(0, git_repository_is_shallow(g_repo));
+}
+
+void test_grafts_shallow__shallow_repo(void)
+{
+	g_repo = cl_git_sandbox_init("shallow.git");
+	cl_assert_equal_i(1, git_repository_is_shallow(g_repo));
+}
+
+void test_grafts_shallow__clears_errors(void)
+{
+	g_repo = cl_git_sandbox_init("testrepo.git");
+	cl_assert_equal_i(0, git_repository_is_shallow(g_repo));
+	cl_assert_equal_p(NULL, git_error_last());
+}
+
+void test_grafts_shallow__shallow_oids(void)
+{
+	git_commit_graft *graft;
+	git_grafts *grafts;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+	cl_assert_equal_i(1, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &g_shallow_oid));
+}
+
+void test_grafts_shallow__cache_clearing(void)
+{
+	git_commit_graft *graft;
+	git_grafts *grafts;
+	git_oid tmp_oid;
+
+	cl_git_pass(git_oid__fromstr(&tmp_oid, "0000000000000000000000000000000000000000", GIT_OID_SHA1));
+	g_repo = cl_git_sandbox_init("shallow.git");
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+
+	cl_assert_equal_i(1, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &g_shallow_oid));
+
+	cl_git_mkfile("shallow.git/shallow",
+		"be3563ae3f795b2b4353bcce3a527ad0a4f7f644\n"
+		"0000000000000000000000000000000000000000\n"
+	);
+
+	cl_git_pass(git_grafts_refresh(grafts));
+	cl_assert_equal_i(2, git_grafts_size(grafts));
+	cl_git_pass(git_grafts_get(&graft, grafts, &g_shallow_oid));
+	cl_git_pass(git_grafts_get(&graft, grafts, &tmp_oid));
+
+	cl_git_pass(p_unlink("shallow.git/shallow"));
+	cl_git_pass(git_grafts_refresh(grafts));
+	cl_assert_equal_i(0, git_grafts_size(grafts));
+}
+
+void test_grafts_shallow__errors_on_borked(void)
+{
+	git_grafts *grafts;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_mkfile("shallow.git/shallow", "lolno");
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+	cl_git_fail(git_grafts_refresh(grafts));
+	cl_assert_equal_i(0, git_grafts_size(grafts));
+
+	cl_git_mkfile("shallow.git/shallow", "lolno\n");
+	cl_git_pass(git_repository_shallow_grafts__weakptr(&grafts, g_repo));
+	cl_git_fail(git_grafts_refresh(grafts));
+	cl_assert_equal_i(0, git_grafts_size(grafts));
+}
+
+void test_grafts_shallow__revwalk_behavior(void)
+{
+	git_revwalk *w;
+	git_oid oid_1, oid_2, oid_3;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_pass(git_revwalk_new(&w, g_repo));
+	cl_git_pass(git_revwalk_push_head(w));
+
+	cl_git_pass(git_revwalk_next(&oid_1, w)); // a65fedf39aefe402d3bb6e24df4d4f5fe4547750
+	cl_git_pass(git_revwalk_next(&oid_2, w)); // be3563ae3f795b2b4353bcce3a527ad0a4f7f644
+	cl_git_fail_with(GIT_ITEROVER, git_revwalk_next(&oid_3, w));
+
+	cl_assert_equal_s(git_oid_tostr_s(&oid_1), "a65fedf39aefe402d3bb6e24df4d4f5fe4547750");
+	cl_assert_equal_s(git_oid_tostr_s(&oid_2), "be3563ae3f795b2b4353bcce3a527ad0a4f7f644");
+
+	git_revwalk_free(w);
+}
+
+void test_grafts_shallow__grafted_object(void)
+{
+	git_commit *commit;
+
+	g_repo = cl_git_sandbox_init("shallow.git");
+
+	cl_git_pass(git_commit_lookup(&commit, g_repo, &g_shallow_oid));
+
+	cl_assert_equal_i(0, git_commit_parentcount(commit));
+
+	git_commit_free(commit);
+}

tests/libgit2/online/shallow.c

+#include "clar_libgit2.h"
+#include "futils.h"
+#include "repository.h"
+
+static int remote_single_branch(git_remote **out, git_repository *repo, const char *name, const char *url, void *payload)
+{
+	GIT_UNUSED(payload);
+
+	cl_git_pass(git_remote_create_with_fetchspec(out, repo, name, url, "+refs/heads/master:refs/remotes/origin/master"));
+
+	return 0;
+}
+
+void test_online_shallow__clone_depth_zero(void)
+{
+	git_str path = GIT_STR_INIT;
+	git_repository *repo;
+	git_clone_options clone_opts = GIT_CLONE_OPTIONS_INIT;
+	git_oid *roots;
+	size_t roots_len;
+
+	clone_opts.fetch_opts.depth = 0;
+	clone_opts.remote_cb = remote_single_branch;
+
+	git_str_joinpath(&path, clar_sandbox_path(), "shallowclone_0");
+
+	cl_git_pass(git_clone(&repo, "https://github.com/libgit2/TestGitRepository", git_str_cstr(&path), &clone_opts));
+
+	/* cloning with depth 0 results in a full clone. */
+	cl_assert_equal_b(false, git_repository_is_shallow(repo));
+
+	/* full clones do not have shallow roots. */
+	cl_git_pass(git_repository__shallow_roots(&roots, &roots_len, repo));
+	cl_assert_equal_i(0, roots_len);
+
+	git__free(roots);
+	git_str_dispose(&path);
+	git_repository_free(repo);
+}
+
+void test_online_shallow__clone_depth_one(void)
+{
+	git_str path = GIT_STR_INIT;
+	git_repository *repo;
+	git_revwalk *walk;
+	git_clone_options clone_opts = GIT_CLONE_OPTIONS_INIT;
+	git_oid oid;
+	git_oid *roots;
+	size_t roots_len;
+	size_t num_commits = 0;
+	int error = 0;
+
+	clone_opts.fetch_opts.depth = 1;
+	clone_opts.remote_cb = remote_single_branch;
+
+	git_str_joinpath(&path, clar_sandbox_path(), "shallowclone_1");
+
+	cl_git_pass(git_clone(&repo, "https://github.com/libgit2/TestGitRepository", git_str_cstr(&path), &clone_opts));
+
+	cl_assert_equal_b(true, git_repository_is_shallow(repo));
+
+	cl_git_pass(git_repository__shallow_roots(&roots, &roots_len, repo));
+	cl_assert_equal_i(1, roots_len);
+	cl_assert_equal_s("49322bb17d3acc9146f98c97d078513228bbf3c0", git_oid_tostr_s(&roots[0]));
+
+	git_revwalk_new(&walk, repo);
+
+	git_revwalk_push_head(walk);
+
+	while ((error = git_revwalk_next(&oid, walk)) == GIT_OK) {
+		num_commits++;
+	}
+
+	cl_assert_equal_i(num_commits, 1);
+	cl_assert_equal_i(error, GIT_ITEROVER);
+
+	git__free(roots);
+	git_str_dispose(&path);
+	git_revwalk_free(walk);
+	git_repository_free(repo);
+}
+
+void test_online_shallow__clone_depth_five(void)
+{
+	git_str path = GIT_STR_INIT;
+	git_repository *repo;
+	git_revwalk *walk;
+	git_clone_options clone_opts = GIT_CLONE_OPTIONS_INIT;
+	git_oid oid;
+	git_oid *roots;
+	size_t roots_len;
+	size_t num_commits = 0;
+	int error = 0;
+
+	clone_opts.fetch_opts.depth = 5;
+	clone_opts.remote_cb = remote_single_branch;
+
+	git_str_joinpath(&path, clar_sandbox_path(), "shallowclone_5");
+
+	cl_git_pass(git_clone(&repo, "https://github.com/libgit2/TestGitRepository", git_str_cstr(&path), &clone_opts));
+
+	cl_assert_equal_b(true, git_repository_is_shallow(repo));
+
+	cl_git_pass(git_repository__shallow_roots(&roots, &roots_len, repo));
+	cl_assert_equal_i(3, roots_len);
+	cl_assert_equal_s("c070ad8c08840c8116da865b2d65593a6bb9cd2a", git_oid_tostr_s(&roots[0]));
+	cl_assert_equal_s("0966a434eb1a025db6b71485ab63a3bfbea520b6", git_oid_tostr_s(&roots[1]));
+	cl_assert_equal_s("83834a7afdaa1a1260568567f6ad90020389f664", git_oid_tostr_s(&roots[2]));
+
+	git_revwalk_new(&walk, repo);
+
+	git_revwalk_push_head(walk);
+
+	while ((error = git_revwalk_next(&oid, walk)) == GIT_OK) {
+		num_commits++;
+	}
+
+	cl_assert_equal_i(num_commits, 13);
+	cl_assert_equal_i(error, GIT_ITEROVER);
+
+	git__free(roots);
+	git_str_dispose(&path);
+	git_revwalk_free(walk);
+	git_repository_free(repo);
+}
+
+void test_online_shallow__unshallow(void)
+{
+	git_str path = GIT_STR_INIT;
+	git_repository *repo;
+	git_revwalk *walk;
+	git_clone_options clone_opts = GIT_CLONE_OPTIONS_INIT;
+	git_fetch_options fetch_opts = GIT_FETCH_OPTIONS_INIT;
+	git_remote *origin = NULL;
+	git_oid oid;
+	size_t num_commits = 0;
+	int error = 0;
+
+	clone_opts.fetch_opts.depth = 5;
+	clone_opts.remote_cb = remote_single_branch;
+
+	git_str_joinpath(&path, clar_sandbox_path(), "unshallow");
+	cl_git_pass(git_clone(&repo, "https://github.com/libgit2/TestGitRepository", git_str_cstr(&path), &clone_opts));
+	cl_assert_equal_b(true, git_repository_is_shallow(repo));
+
+	fetch_opts.depth = GIT_FETCH_DEPTH_UNSHALLOW;
+	cl_git_pass(git_remote_lookup(&origin, repo, "origin"));
+
+	cl_git_pass(git_remote_fetch(origin, NULL, &fetch_opts, NULL));
+	cl_assert_equal_b(false, git_repository_is_shallow(repo));
+
+	git_revwalk_new(&walk, repo);
+	git_revwalk_push_head(walk);
+
+	while ((error = git_revwalk_next(&oid, walk)) == GIT_OK) {
+		num_commits++;
+	}
+
+	cl_assert_equal_i(num_commits, 21);
+	cl_assert_equal_i(error, GIT_ITEROVER);
+
+	git_remote_free(origin);
+	git_str_dispose(&path);
+	git_revwalk_free(walk);
+	git_repository_free(repo);
+}

tests/libgit2/transports/smart/packet.c

@@ -25,7 +25,7 @@ static void assert_data_pkt_parses(const char *line, const char *expected_data,
 	size_t linelen = strlen(line) + 1;
 	const char *endptr;
 	git_pkt_data *pkt;
-	git_pkt_parse_data pkt_parse_data = { 0 };
+	git_pkt_parse_data pkt_parse_data = { 1, GIT_OID_SHA1 };
 
 	cl_git_pass(git_pkt_parse_line((git_pkt **) &pkt, &endptr, line, linelen, &pkt_parse_data));
 	cl_assert_equal_i(pkt->type, GIT_PKT_DATA);
@@ -71,7 +71,7 @@ static void assert_ack_parses(const char *line, const char *expected_oid, enum g
 	const char *endptr;
 	git_pkt_ack *pkt;
 	git_oid oid;
-	git_pkt_parse_data pkt_parse_data = { 0 };
+	git_pkt_parse_data pkt_parse_data = { 1, GIT_OID_SHA1 };
 
 	cl_git_pass(git_oid__fromstr(&oid, expected_oid, GIT_OID_SHA1));
 

tests/resources/grafted.git/HEAD

+ref: refs/heads/master

tests/resources/grafted.git/config

+[core]
+	repositoryformatversion = 0
+	filemode = true
+	bare = true
+	ignorecase = true
+	precomposeunicode = true

tests/resources/grafted.git/info/grafts

+f503807ffa920e407a600cfaee96b7152259acc7 2f3053cbff8a4ca2f0666de364ddb734a28a31a9
+0512adebd3782157f0d5c9b22b043f87b4aaff9e 2f3053cbff8a4ca2f0666de364ddb734a28a31a9
+66cc22a015f6ca75b34c82d28f78ba663876bade e414f42f4e6bc6934563a2349a8600f0ab68618e 8a00e91619098618be97c0d2ceabb05a2c58edd9 1c18e80a276611bb9b146590616bbc5aebdf2945 2f3053cbff8a4ca2f0666de364ddb734a28a31a9

tests/resources/grafted.git/refs/heads/bottom

+66cc22a015f6ca75b34c82d28f78ba663876bade

tests/resources/grafted.git/refs/heads/branch

+8a00e91619098618be97c0d2ceabb05a2c58edd9

tests/resources/grafted.git/refs/heads/master

+2f3053cbff8a4ca2f0666de364ddb734a28a31a9

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