chore(3p/git): Unvendor git and track patches instead r/2903

This was vendored a long time ago under the expectation that keeping
it in sync with cgit would be easier this way, but it has proven not
to be a big issue.

On the other hand, a vendored copy of git is an annoying maintenance
burden. It is much easier to rebase the single (dottime) patch that we
have.

This removes the vendored copy of git and instead passes the git
source code to cgit via `pkgs.srcOnly`, which includes the applied
patch so that cgit can continue rendering dottime.

Change-Id: If31f62dea7ce688fd1b9050204e9378019775f2b

1 files changed, 0 insertions, 1051 deletions

diff --git a/third_party/git/builtin/pull.c b/third_party/git/builtin/pull.c
deleted file mode 100644
index 425950f46973..000000000000
--- a/third_party/git/builtin/pull.c
+++ /dev/null
@@ -1,1051 +0,0 @@
-/*
- * Builtin "git pull"
- *
- * Based on git-pull.sh by Junio C Hamano
- *
- * Fetch one or more remote refs and merge it/them into the current HEAD.
- */
-#define USE_THE_INDEX_COMPATIBILITY_MACROS
-#include "cache.h"
-#include "config.h"
-#include "builtin.h"
-#include "parse-options.h"
-#include "exec-cmd.h"
-#include "run-command.h"
-#include "oid-array.h"
-#include "remote.h"
-#include "dir.h"
-#include "rebase.h"
-#include "refs.h"
-#include "refspec.h"
-#include "revision.h"
-#include "submodule.h"
-#include "submodule-config.h"
-#include "tempfile.h"
-#include "lockfile.h"
-#include "wt-status.h"
-#include "commit-reach.h"
-#include "sequencer.h"
-
-/**
- * Parses the value of --rebase. If value is a false value, returns
- * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
- * "merges", returns REBASE_MERGES. If value is "preserve", returns
- * REBASE_PRESERVE. If value is a invalid value, dies with a fatal error if
- * fatal is true, otherwise returns REBASE_INVALID.
- */
-static enum rebase_type parse_config_rebase(const char *key, const char *value,
-		int fatal)
-{
-	enum rebase_type v = rebase_parse_value(value);
-	if (v != REBASE_INVALID)
-		return v;
-
-	if (fatal)
-		die(_("Invalid value for %s: %s"), key, value);
-	else
-		error(_("Invalid value for %s: %s"), key, value);
-
-	return REBASE_INVALID;
-}
-
-/**
- * Callback for --rebase, which parses arg with parse_config_rebase().
- */
-static int parse_opt_rebase(const struct option *opt, const char *arg, int unset)
-{
-	enum rebase_type *value = opt->value;
-
-	if (arg)
-		*value = parse_config_rebase("--rebase", arg, 0);
-	else
-		*value = unset ? REBASE_FALSE : REBASE_TRUE;
-	return *value == REBASE_INVALID ? -1 : 0;
-}
-
-static const char * const pull_usage[] = {
-	N_("git pull [<options>] [<repository> [<refspec>...]]"),
-	NULL
-};
-
-/* Shared options */
-static int opt_verbosity;
-static char *opt_progress;
-static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
-
-/* Options passed to git-merge or git-rebase */
-static enum rebase_type opt_rebase = -1;
-static char *opt_diffstat;
-static char *opt_log;
-static char *opt_signoff;
-static char *opt_squash;
-static char *opt_commit;
-static char *opt_edit;
-static char *cleanup_arg;
-static char *opt_ff;
-static char *opt_verify_signatures;
-static int opt_autostash = -1;
-static int config_autostash;
-static int check_trust_level = 1;
-static struct strvec opt_strategies = STRVEC_INIT;
-static struct strvec opt_strategy_opts = STRVEC_INIT;
-static char *opt_gpg_sign;
-static int opt_allow_unrelated_histories;
-
-/* Options passed to git-fetch */
-static char *opt_all;
-static char *opt_append;
-static char *opt_upload_pack;
-static int opt_force;
-static char *opt_tags;
-static char *opt_prune;
-static char *max_children;
-static int opt_dry_run;
-static char *opt_keep;
-static char *opt_depth;
-static char *opt_unshallow;
-static char *opt_update_shallow;
-static char *opt_refmap;
-static char *opt_ipv4;
-static char *opt_ipv6;
-static int opt_show_forced_updates = -1;
-static char *set_upstream;
-static struct strvec opt_fetch = STRVEC_INIT;
-
-static struct option pull_options[] = {
-	/* Shared options */
-	OPT__VERBOSITY(&opt_verbosity),
-	OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
-		N_("force progress reporting"),
-		PARSE_OPT_NOARG),
-	OPT_CALLBACK_F(0, "recurse-submodules",
-		   &recurse_submodules, N_("on-demand"),
-		   N_("control for recursive fetching of submodules"),
-		   PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules),
-
-	/* Options passed to git-merge or git-rebase */
-	OPT_GROUP(N_("Options related to merging")),
-	OPT_CALLBACK_F('r', "rebase", &opt_rebase,
-	  "(false|true|merges|preserve|interactive)",
-	  N_("incorporate changes by rebasing rather than merging"),
-	  PARSE_OPT_OPTARG, parse_opt_rebase),
-	OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
-		N_("do not show a diffstat at the end of the merge"),
-		PARSE_OPT_NOARG | PARSE_OPT_NONEG),
-	OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL,
-		N_("show a diffstat at the end of the merge"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL,
-		N_("(synonym to --stat)"),
-		PARSE_OPT_NOARG | PARSE_OPT_HIDDEN),
-	OPT_PASSTHRU(0, "log", &opt_log, N_("n"),
-		N_("add (at most <n>) entries from shortlog to merge commit message"),
-		PARSE_OPT_OPTARG),
-	OPT_PASSTHRU(0, "signoff", &opt_signoff, NULL,
-		N_("add Signed-off-by:"),
-		PARSE_OPT_OPTARG),
-	OPT_PASSTHRU(0, "squash", &opt_squash, NULL,
-		N_("create a single commit instead of doing a merge"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "commit", &opt_commit, NULL,
-		N_("perform a commit if the merge succeeds (default)"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "edit", &opt_edit, NULL,
-		N_("edit message before committing"),
-		PARSE_OPT_NOARG),
-	OPT_CLEANUP(&cleanup_arg),
-	OPT_PASSTHRU(0, "ff", &opt_ff, NULL,
-		N_("allow fast-forward"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL,
-		N_("abort if fast-forward is not possible"),
-		PARSE_OPT_NOARG | PARSE_OPT_NONEG),
-	OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL,
-		N_("verify that the named commit has a valid GPG signature"),
-		PARSE_OPT_NOARG),
-	OPT_BOOL(0, "autostash", &opt_autostash,
-		N_("automatically stash/stash pop before and after")),
-	OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
-		N_("merge strategy to use"),
-		0),
-	OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts,
-		N_("option=value"),
-		N_("option for selected merge strategy"),
-		0),
-	OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"),
-		N_("GPG sign commit"),
-		PARSE_OPT_OPTARG),
-	OPT_SET_INT(0, "allow-unrelated-histories",
-		    &opt_allow_unrelated_histories,
-		    N_("allow merging unrelated histories"), 1),
-
-	/* Options passed to git-fetch */
-	OPT_GROUP(N_("Options related to fetching")),
-	OPT_PASSTHRU(0, "all", &opt_all, NULL,
-		N_("fetch from all remotes"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU('a', "append", &opt_append, NULL,
-		N_("append to .git/FETCH_HEAD instead of overwriting"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"),
-		N_("path to upload pack on remote end"),
-		0),
-	OPT__FORCE(&opt_force, N_("force overwrite of local branch"), 0),
-	OPT_PASSTHRU('t', "tags", &opt_tags, NULL,
-		N_("fetch all tags and associated objects"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU('p', "prune", &opt_prune, NULL,
-		N_("prune remote-tracking branches no longer on remote"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU('j', "jobs", &max_children, N_("n"),
-		N_("number of submodules pulled in parallel"),
-		PARSE_OPT_OPTARG),
-	OPT_BOOL(0, "dry-run", &opt_dry_run,
-		N_("dry run")),
-	OPT_PASSTHRU('k', "keep", &opt_keep, NULL,
-		N_("keep downloaded pack"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
-		N_("deepen history of shallow clone"),
-		0),
-	OPT_PASSTHRU_ARGV(0, "shallow-since", &opt_fetch, N_("time"),
-		N_("deepen history of shallow repository based on time"),
-		0),
-	OPT_PASSTHRU_ARGV(0, "shallow-exclude", &opt_fetch, N_("revision"),
-		N_("deepen history of shallow clone, excluding rev"),
-		0),
-	OPT_PASSTHRU_ARGV(0, "deepen", &opt_fetch, N_("n"),
-		N_("deepen history of shallow clone"),
-		0),
-	OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
-		N_("convert to a complete repository"),
-		PARSE_OPT_NONEG | PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL,
-		N_("accept refs that update .git/shallow"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
-		N_("specify fetch refmap"),
-		PARSE_OPT_NONEG),
-	OPT_PASSTHRU_ARGV('o', "server-option", &opt_fetch,
-		N_("server-specific"),
-		N_("option to transmit"),
-		0),
-	OPT_PASSTHRU('4',  "ipv4", &opt_ipv4, NULL,
-		N_("use IPv4 addresses only"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU('6',  "ipv6", &opt_ipv6, NULL,
-		N_("use IPv6 addresses only"),
-		PARSE_OPT_NOARG),
-	OPT_PASSTHRU_ARGV(0, "negotiation-tip", &opt_fetch, N_("revision"),
-		N_("report that we have only objects reachable from this object"),
-		0),
-	OPT_BOOL(0, "show-forced-updates", &opt_show_forced_updates,
-		 N_("check for forced-updates on all updated branches")),
-	OPT_PASSTHRU(0, "set-upstream", &set_upstream, NULL,
-		N_("set upstream for git pull/fetch"),
-		PARSE_OPT_NOARG),
-
-	OPT_END()
-};
-
-/**
- * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
- */
-static void argv_push_verbosity(struct strvec *arr)
-{
-	int verbosity;
-
-	for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
-		strvec_push(arr, "-v");
-
-	for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
-		strvec_push(arr, "-q");
-}
-
-/**
- * Pushes "-f" switches into arr to match the opt_force level.
- */
-static void argv_push_force(struct strvec *arr)
-{
-	int force = opt_force;
-	while (force-- > 0)
-		strvec_push(arr, "-f");
-}
-
-/**
- * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv
- */
-static void set_reflog_message(int argc, const char **argv)
-{
-	int i;
-	struct strbuf msg = STRBUF_INIT;
-
-	for (i = 0; i < argc; i++) {
-		if (i)
-			strbuf_addch(&msg, ' ');
-		strbuf_addstr(&msg, argv[i]);
-	}
-
-	setenv("GIT_REFLOG_ACTION", msg.buf, 0);
-
-	strbuf_release(&msg);
-}
-
-/**
- * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If
- * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns
- * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an
- * error.
- */
-static const char *config_get_ff(void)
-{
-	const char *value;
-
-	if (git_config_get_value("pull.ff", &value))
-		return NULL;
-
-	switch (git_parse_maybe_bool(value)) {
-	case 0:
-		return "--no-ff";
-	case 1:
-		return "--ff";
-	}
-
-	if (!strcmp(value, "only"))
-		return "--ff-only";
-
-	die(_("Invalid value for pull.ff: %s"), value);
-}
-
-/**
- * Returns the default configured value for --rebase. It first looks for the
- * value of "branch.$curr_branch.rebase", where $curr_branch is the current
- * branch, and if HEAD is detached or the configuration key does not exist,
- * looks for the value of "pull.rebase". If both configuration keys do not
- * exist, returns REBASE_FALSE.
- */
-static enum rebase_type config_get_rebase(void)
-{
-	struct branch *curr_branch = branch_get("HEAD");
-	const char *value;
-
-	if (curr_branch) {
-		char *key = xstrfmt("branch.%s.rebase", curr_branch->name);
-
-		if (!git_config_get_value(key, &value)) {
-			enum rebase_type ret = parse_config_rebase(key, value, 1);
-			free(key);
-			return ret;
-		}
-
-		free(key);
-	}
-
-	if (!git_config_get_value("pull.rebase", &value))
-		return parse_config_rebase("pull.rebase", value, 1);
-
-	if (opt_verbosity >= 0 && !opt_ff) {
-		warning(_("Pulling without specifying how to reconcile divergent branches is\n"
-			"discouraged. You can squelch this message by running one of the following\n"
-			"commands sometime before your next pull:\n"
-			"\n"
-			"  git config pull.rebase false  # merge (the default strategy)\n"
-			"  git config pull.rebase true   # rebase\n"
-			"  git config pull.ff only       # fast-forward only\n"
-			"\n"
-			"You can replace \"git config\" with \"git config --global\" to set a default\n"
-			"preference for all repositories. You can also pass --rebase, --no-rebase,\n"
-			"or --ff-only on the command line to override the configured default per\n"
-			"invocation.\n"));
-	}
-
-	return REBASE_FALSE;
-}
-
-/**
- * Read config variables.
- */
-static int git_pull_config(const char *var, const char *value, void *cb)
-{
-	int status;
-
-	if (!strcmp(var, "rebase.autostash")) {
-		config_autostash = git_config_bool(var, value);
-		return 0;
-	} else if (!strcmp(var, "submodule.recurse")) {
-		recurse_submodules = git_config_bool(var, value) ?
-			RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
-		return 0;
-	} else if (!strcmp(var, "gpg.mintrustlevel")) {
-		check_trust_level = 0;
-	}
-
-	status = git_gpg_config(var, value, cb);
-	if (status)
-		return status;
-
-	return git_default_config(var, value, cb);
-}
-
-/**
- * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge
- * into merge_heads.
- */
-static void get_merge_heads(struct oid_array *merge_heads)
-{
-	const char *filename = git_path_fetch_head(the_repository);
-	FILE *fp;
-	struct strbuf sb = STRBUF_INIT;
-	struct object_id oid;
-
-	fp = xfopen(filename, "r");
-	while (strbuf_getline_lf(&sb, fp) != EOF) {
-		const char *p;
-		if (parse_oid_hex(sb.buf, &oid, &p))
-			continue;  /* invalid line: does not start with object ID */
-		if (starts_with(p, "\tnot-for-merge\t"))
-			continue;  /* ref is not-for-merge */
-		oid_array_append(merge_heads, &oid);
-	}
-	fclose(fp);
-	strbuf_release(&sb);
-}
-
-/**
- * Used by die_no_merge_candidates() as a for_each_remote() callback to
- * retrieve the name of the remote if the repository only has one remote.
- */
-static int get_only_remote(struct remote *remote, void *cb_data)
-{
-	const char **remote_name = cb_data;
-
-	if (*remote_name)
-		return -1;
-
-	*remote_name = remote->name;
-	return 0;
-}
-
-/**
- * Dies with the appropriate reason for why there are no merge candidates:
- *
- * 1. We fetched from a specific remote, and a refspec was given, but it ended
- *    up not fetching anything. This is usually because the user provided a
- *    wildcard refspec which had no matches on the remote end.
- *
- * 2. We fetched from a non-default remote, but didn't specify a branch to
- *    merge. We can't use the configured one because it applies to the default
- *    remote, thus the user must specify the branches to merge.
- *
- * 3. We fetched from the branch's or repo's default remote, but:
- *
- *    a. We are not on a branch, so there will never be a configured branch to
- *       merge with.
- *
- *    b. We are on a branch, but there is no configured branch to merge with.
- *
- * 4. We fetched from the branch's or repo's default remote, but the configured
- *    branch to merge didn't get fetched. (Either it doesn't exist, or wasn't
- *    part of the configured fetch refspec.)
- */
-static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs)
-{
-	struct branch *curr_branch = branch_get("HEAD");
-	const char *remote = curr_branch ? curr_branch->remote_name : NULL;
-
-	if (*refspecs) {
-		if (opt_rebase)
-			fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched."));
-		else
-			fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched."));
-		fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n"
-					"matches on the remote end."));
-	} else if (repo && curr_branch && (!remote || strcmp(repo, remote))) {
-		fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n"
-			"a branch. Because this is not the default configured remote\n"
-			"for your current branch, you must specify a branch on the command line."),
-			repo);
-	} else if (!curr_branch) {
-		fprintf_ln(stderr, _("You are not currently on a branch."));
-		if (opt_rebase)
-			fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
-		else
-			fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
-		fprintf_ln(stderr, _("See git-pull(1) for details."));
-		fprintf(stderr, "\n");
-		fprintf_ln(stderr, "    git pull %s %s", _("<remote>"), _("<branch>"));
-		fprintf(stderr, "\n");
-	} else if (!curr_branch->merge_nr) {
-		const char *remote_name = NULL;
-
-		if (for_each_remote(get_only_remote, &remote_name) || !remote_name)
-			remote_name = _("<remote>");
-
-		fprintf_ln(stderr, _("There is no tracking information for the current branch."));
-		if (opt_rebase)
-			fprintf_ln(stderr, _("Please specify which branch you want to rebase against."));
-		else
-			fprintf_ln(stderr, _("Please specify which branch you want to merge with."));
-		fprintf_ln(stderr, _("See git-pull(1) for details."));
-		fprintf(stderr, "\n");
-		fprintf_ln(stderr, "    git pull %s %s", _("<remote>"), _("<branch>"));
-		fprintf(stderr, "\n");
-		fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:"));
-		fprintf(stderr, "\n");
-		fprintf_ln(stderr, "    git branch --set-upstream-to=%s/%s %s\n",
-				remote_name, _("<branch>"), curr_branch->name);
-	} else
-		fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n"
-			"from the remote, but no such ref was fetched."),
-			*curr_branch->merge_name);
-	exit(1);
-}
-
-/**
- * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
- * as a string and `refspecs` as a null-terminated array of strings. If `repo`
- * is not provided in argv, it is set to NULL.
- */
-static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
-		const char ***refspecs)
-{
-	if (argc > 0) {
-		*repo = *argv++;
-		argc--;
-	} else
-		*repo = NULL;
-	*refspecs = argv;
-}
-
-/**
- * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
- * repository and refspecs to fetch, or NULL if they are not provided.
- */
-static int run_fetch(const char *repo, const char **refspecs)
-{
-	struct strvec args = STRVEC_INIT;
-	int ret;
-
-	strvec_pushl(&args, "fetch", "--update-head-ok", NULL);
-
-	/* Shared options */
-	argv_push_verbosity(&args);
-	if (opt_progress)
-		strvec_push(&args, opt_progress);
-
-	/* Options passed to git-fetch */
-	if (opt_all)
-		strvec_push(&args, opt_all);
-	if (opt_append)
-		strvec_push(&args, opt_append);
-	if (opt_upload_pack)
-		strvec_push(&args, opt_upload_pack);
-	argv_push_force(&args);
-	if (opt_tags)
-		strvec_push(&args, opt_tags);
-	if (opt_prune)
-		strvec_push(&args, opt_prune);
-	if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT)
-		switch (recurse_submodules) {
-		case RECURSE_SUBMODULES_ON:
-			strvec_push(&args, "--recurse-submodules=on");
-			break;
-		case RECURSE_SUBMODULES_OFF:
-			strvec_push(&args, "--recurse-submodules=no");
-			break;
-		case RECURSE_SUBMODULES_ON_DEMAND:
-			strvec_push(&args, "--recurse-submodules=on-demand");
-			break;
-		default:
-			BUG("submodule recursion option not understood");
-		}
-	if (max_children)
-		strvec_push(&args, max_children);
-	if (opt_dry_run)
-		strvec_push(&args, "--dry-run");
-	if (opt_keep)
-		strvec_push(&args, opt_keep);
-	if (opt_depth)
-		strvec_push(&args, opt_depth);
-	if (opt_unshallow)
-		strvec_push(&args, opt_unshallow);
-	if (opt_update_shallow)
-		strvec_push(&args, opt_update_shallow);
-	if (opt_refmap)
-		strvec_push(&args, opt_refmap);
-	if (opt_ipv4)
-		strvec_push(&args, opt_ipv4);
-	if (opt_ipv6)
-		strvec_push(&args, opt_ipv6);
-	if (opt_show_forced_updates > 0)
-		strvec_push(&args, "--show-forced-updates");
-	else if (opt_show_forced_updates == 0)
-		strvec_push(&args, "--no-show-forced-updates");
-	if (set_upstream)
-		strvec_push(&args, set_upstream);
-	strvec_pushv(&args, opt_fetch.v);
-
-	if (repo) {
-		strvec_push(&args, repo);
-		strvec_pushv(&args, refspecs);
-	} else if (*refspecs)
-		BUG("refspecs without repo?");
-	ret = run_command_v_opt(args.v, RUN_GIT_CMD);
-	strvec_clear(&args);
-	return ret;
-}
-
-/**
- * "Pulls into void" by branching off merge_head.
- */
-static int pull_into_void(const struct object_id *merge_head,
-		const struct object_id *curr_head)
-{
-	if (opt_verify_signatures) {
-		struct commit *commit;
-
-		commit = lookup_commit(the_repository, merge_head);
-		if (!commit)
-			die(_("unable to access commit %s"),
-			    oid_to_hex(merge_head));
-
-		verify_merge_signature(commit, opt_verbosity,
-				       check_trust_level);
-	}
-
-	/*
-	 * Two-way merge: we treat the index as based on an empty tree,
-	 * and try to fast-forward to HEAD. This ensures we will not lose
-	 * index/worktree changes that the user already made on the unborn
-	 * branch.
-	 */
-	if (checkout_fast_forward(the_repository,
-				  the_hash_algo->empty_tree,
-				  merge_head, 0))
-		return 1;
-
-	if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR))
-		return 1;
-
-	return 0;
-}
-
-static int rebase_submodules(void)
-{
-	struct child_process cp = CHILD_PROCESS_INIT;
-
-	cp.git_cmd = 1;
-	cp.no_stdin = 1;
-	strvec_pushl(&cp.args, "submodule", "update",
-		     "--recursive", "--rebase", NULL);
-	argv_push_verbosity(&cp.args);
-
-	return run_command(&cp);
-}
-
-static int update_submodules(void)
-{
-	struct child_process cp = CHILD_PROCESS_INIT;
-
-	cp.git_cmd = 1;
-	cp.no_stdin = 1;
-	strvec_pushl(&cp.args, "submodule", "update",
-		     "--recursive", "--checkout", NULL);
-	argv_push_verbosity(&cp.args);
-
-	return run_command(&cp);
-}
-
-/**
- * Runs git-merge, returning its exit status.
- */
-static int run_merge(void)
-{
-	int ret;
-	struct strvec args = STRVEC_INIT;
-
-	strvec_pushl(&args, "merge", NULL);
-
-	/* Shared options */
-	argv_push_verbosity(&args);
-	if (opt_progress)
-		strvec_push(&args, opt_progress);
-
-	/* Options passed to git-merge */
-	if (opt_diffstat)
-		strvec_push(&args, opt_diffstat);
-	if (opt_log)
-		strvec_push(&args, opt_log);
-	if (opt_signoff)
-		strvec_push(&args, opt_signoff);
-	if (opt_squash)
-		strvec_push(&args, opt_squash);
-	if (opt_commit)
-		strvec_push(&args, opt_commit);
-	if (opt_edit)
-		strvec_push(&args, opt_edit);
-	if (cleanup_arg)
-		strvec_pushf(&args, "--cleanup=%s", cleanup_arg);
-	if (opt_ff)
-		strvec_push(&args, opt_ff);
-	if (opt_verify_signatures)
-		strvec_push(&args, opt_verify_signatures);
-	strvec_pushv(&args, opt_strategies.v);
-	strvec_pushv(&args, opt_strategy_opts.v);
-	if (opt_gpg_sign)
-		strvec_push(&args, opt_gpg_sign);
-	if (opt_autostash == 0)
-		strvec_push(&args, "--no-autostash");
-	else if (opt_autostash == 1)
-		strvec_push(&args, "--autostash");
-	if (opt_allow_unrelated_histories > 0)
-		strvec_push(&args, "--allow-unrelated-histories");
-
-	strvec_push(&args, "FETCH_HEAD");
-	ret = run_command_v_opt(args.v, RUN_GIT_CMD);
-	strvec_clear(&args);
-	return ret;
-}
-
-/**
- * Returns remote's upstream branch for the current branch. If remote is NULL,
- * the current branch's configured default remote is used. Returns NULL if
- * `remote` does not name a valid remote, HEAD does not point to a branch,
- * remote is not the branch's configured remote or the branch does not have any
- * configured upstream branch.
- */
-static const char *get_upstream_branch(const char *remote)
-{
-	struct remote *rm;
-	struct branch *curr_branch;
-	const char *curr_branch_remote;
-
-	rm = remote_get(remote);
-	if (!rm)
-		return NULL;
-
-	curr_branch = branch_get("HEAD");
-	if (!curr_branch)
-		return NULL;
-
-	curr_branch_remote = remote_for_branch(curr_branch, NULL);
-	assert(curr_branch_remote);
-
-	if (strcmp(curr_branch_remote, rm->name))
-		return NULL;
-
-	return branch_get_upstream(curr_branch, NULL);
-}
-
-/**
- * Derives the remote-tracking branch from the remote and refspec.
- *
- * FIXME: The current implementation assumes the default mapping of
- * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>.
- */
-static const char *get_tracking_branch(const char *remote, const char *refspec)
-{
-	struct refspec_item spec;
-	const char *spec_src;
-	const char *merge_branch;
-
-	refspec_item_init_or_die(&spec, refspec, REFSPEC_FETCH);
-	spec_src = spec.src;
-	if (!*spec_src || !strcmp(spec_src, "HEAD"))
-		spec_src = "HEAD";
-	else if (skip_prefix(spec_src, "heads/", &spec_src))
-		;
-	else if (skip_prefix(spec_src, "refs/heads/", &spec_src))
-		;
-	else if (starts_with(spec_src, "refs/") ||
-		starts_with(spec_src, "tags/") ||
-		starts_with(spec_src, "remotes/"))
-		spec_src = "";
-
-	if (*spec_src) {
-		if (!strcmp(remote, "."))
-			merge_branch = mkpath("refs/heads/%s", spec_src);
-		else
-			merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src);
-	} else
-		merge_branch = NULL;
-
-	refspec_item_clear(&spec);
-	return merge_branch;
-}
-
-/**
- * Given the repo and refspecs, sets fork_point to the point at which the
- * current branch forked from its remote-tracking branch. Returns 0 on success,
- * -1 on failure.
- */
-static int get_rebase_fork_point(struct object_id *fork_point, const char *repo,
-		const char *refspec)
-{
-	int ret;
-	struct branch *curr_branch;
-	const char *remote_branch;
-	struct child_process cp = CHILD_PROCESS_INIT;
-	struct strbuf sb = STRBUF_INIT;
-
-	curr_branch = branch_get("HEAD");
-	if (!curr_branch)
-		return -1;
-
-	if (refspec)
-		remote_branch = get_tracking_branch(repo, refspec);
-	else
-		remote_branch = get_upstream_branch(repo);
-
-	if (!remote_branch)
-		return -1;
-
-	strvec_pushl(&cp.args, "merge-base", "--fork-point",
-		     remote_branch, curr_branch->name, NULL);
-	cp.no_stdin = 1;
-	cp.no_stderr = 1;
-	cp.git_cmd = 1;
-
-	ret = capture_command(&cp, &sb, GIT_MAX_HEXSZ);
-	if (ret)
-		goto cleanup;
-
-	ret = get_oid_hex(sb.buf, fork_point);
-	if (ret)
-		goto cleanup;
-
-cleanup:
-	strbuf_release(&sb);
-	return ret ? -1 : 0;
-}
-
-/**
- * Sets merge_base to the octopus merge base of curr_head, merge_head and
- * fork_point. Returns 0 if a merge base is found, 1 otherwise.
- */
-static int get_octopus_merge_base(struct object_id *merge_base,
-		const struct object_id *curr_head,
-		const struct object_id *merge_head,
-		const struct object_id *fork_point)
-{
-	struct commit_list *revs = NULL, *result;
-
-	commit_list_insert(lookup_commit_reference(the_repository, curr_head),
-			   &revs);
-	commit_list_insert(lookup_commit_reference(the_repository, merge_head),
-			   &revs);
-	if (!is_null_oid(fork_point))
-		commit_list_insert(lookup_commit_reference(the_repository, fork_point),
-				   &revs);
-
-	result = get_octopus_merge_bases(revs);
-	free_commit_list(revs);
-	reduce_heads_replace(&result);
-
-	if (!result)
-		return 1;
-
-	oidcpy(merge_base, &result->item->object.oid);
-	free_commit_list(result);
-	return 0;
-}
-
-/**
- * Given the current HEAD oid, the merge head returned from git-fetch and the
- * fork point calculated by get_rebase_fork_point(), runs git-rebase with the
- * appropriate arguments and returns its exit status.
- */
-static int run_rebase(const struct object_id *curr_head,
-		const struct object_id *merge_head,
-		const struct object_id *fork_point)
-{
-	int ret;
-	struct object_id oct_merge_base;
-	struct strvec args = STRVEC_INIT;
-
-	if (!get_octopus_merge_base(&oct_merge_base, curr_head, merge_head, fork_point))
-		if (!is_null_oid(fork_point) && oideq(&oct_merge_base, fork_point))
-			fork_point = NULL;
-
-	strvec_push(&args, "rebase");
-
-	/* Shared options */
-	argv_push_verbosity(&args);
-
-	/* Options passed to git-rebase */
-	if (opt_rebase == REBASE_MERGES)
-		strvec_push(&args, "--rebase-merges");
-	else if (opt_rebase == REBASE_PRESERVE)
-		strvec_push(&args, "--preserve-merges");
-	else if (opt_rebase == REBASE_INTERACTIVE)
-		strvec_push(&args, "--interactive");
-	if (opt_diffstat)
-		strvec_push(&args, opt_diffstat);
-	strvec_pushv(&args, opt_strategies.v);
-	strvec_pushv(&args, opt_strategy_opts.v);
-	if (opt_gpg_sign)
-		strvec_push(&args, opt_gpg_sign);
-	if (opt_autostash == 0)
-		strvec_push(&args, "--no-autostash");
-	else if (opt_autostash == 1)
-		strvec_push(&args, "--autostash");
-	if (opt_verify_signatures &&
-	    !strcmp(opt_verify_signatures, "--verify-signatures"))
-		warning(_("ignoring --verify-signatures for rebase"));
-
-	strvec_push(&args, "--onto");
-	strvec_push(&args, oid_to_hex(merge_head));
-
-	if (fork_point && !is_null_oid(fork_point))
-		strvec_push(&args, oid_to_hex(fork_point));
-	else
-		strvec_push(&args, oid_to_hex(merge_head));
-
-	ret = run_command_v_opt(args.v, RUN_GIT_CMD);
-	strvec_clear(&args);
-	return ret;
-}
-
-int cmd_pull(int argc, const char **argv, const char *prefix)
-{
-	const char *repo, **refspecs;
-	struct oid_array merge_heads = OID_ARRAY_INIT;
-	struct object_id orig_head, curr_head;
-	struct object_id rebase_fork_point;
-	int autostash;
-
-	if (!getenv("GIT_REFLOG_ACTION"))
-		set_reflog_message(argc, argv);
-
-	git_config(git_pull_config, NULL);
-
-	argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0);
-
-	if (cleanup_arg)
-		/*
-		 * this only checks the validity of cleanup_arg; we don't need
-		 * a valid value for use_editor
-		 */
-		get_cleanup_mode(cleanup_arg, 0);
-
-	parse_repo_refspecs(argc, argv, &repo, &refspecs);
-
-	if (!opt_ff)
-		opt_ff = xstrdup_or_null(config_get_ff());
-
-	if (opt_rebase < 0)
-		opt_rebase = config_get_rebase();
-
-	if (read_cache_unmerged())
-		die_resolve_conflict("pull");
-
-	if (file_exists(git_path_merge_head(the_repository)))
-		die_conclude_merge();
-
-	if (get_oid("HEAD", &orig_head))
-		oidclr(&orig_head);
-
-	autostash = config_autostash;
-	if (opt_rebase) {
-		if (opt_autostash != -1)
-			autostash = opt_autostash;
-
-		if (is_null_oid(&orig_head) && !is_cache_unborn())
-			die(_("Updating an unborn branch with changes added to the index."));
-
-		if (!autostash)
-			require_clean_work_tree(the_repository,
-				N_("pull with rebase"),
-				_("please commit or stash them."), 1, 0);
-
-		if (get_rebase_fork_point(&rebase_fork_point, repo, *refspecs))
-			oidclr(&rebase_fork_point);
-	}
-
-	if (run_fetch(repo, refspecs))
-		return 1;
-
-	if (opt_dry_run)
-		return 0;
-
-	if (get_oid("HEAD", &curr_head))
-		oidclr(&curr_head);
-
-	if (!is_null_oid(&orig_head) && !is_null_oid(&curr_head) &&
-			!oideq(&orig_head, &curr_head)) {
-		/*
-		 * The fetch involved updating the current branch.
-		 *
-		 * The working tree and the index file are still based on
-		 * orig_head commit, but we are merging into curr_head.
-		 * Update the working tree to match curr_head.
-		 */
-
-		warning(_("fetch updated the current branch head.\n"
-			"fast-forwarding your working tree from\n"
-			"commit %s."), oid_to_hex(&orig_head));
-
-		if (checkout_fast_forward(the_repository, &orig_head,
-					  &curr_head, 0))
-			die(_("Cannot fast-forward your working tree.\n"
-				"After making sure that you saved anything precious from\n"
-				"$ git diff %s\n"
-				"output, run\n"
-				"$ git reset --hard\n"
-				"to recover."), oid_to_hex(&orig_head));
-	}
-
-	get_merge_heads(&merge_heads);
-
-	if (!merge_heads.nr)
-		die_no_merge_candidates(repo, refspecs);
-
-	if (is_null_oid(&orig_head)) {
-		if (merge_heads.nr > 1)
-			die(_("Cannot merge multiple branches into empty head."));
-		return pull_into_void(merge_heads.oid, &curr_head);
-	}
-	if (opt_rebase && merge_heads.nr > 1)
-		die(_("Cannot rebase onto multiple branches."));
-
-	if (opt_rebase) {
-		int ret = 0;
-		int ran_ff = 0;
-		if ((recurse_submodules == RECURSE_SUBMODULES_ON ||
-		     recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) &&
-		    submodule_touches_in_range(the_repository, &rebase_fork_point, &curr_head))
-			die(_("cannot rebase with locally recorded submodule modifications"));
-		if (!autostash) {
-			struct commit_list *list = NULL;
-			struct commit *merge_head, *head;
-
-			head = lookup_commit_reference(the_repository,
-						       &orig_head);
-			commit_list_insert(head, &list);
-			merge_head = lookup_commit_reference(the_repository,
-							     &merge_heads.oid[0]);
-			if (repo_is_descendant_of(the_repository,
-						  merge_head, list)) {
-				/* we can fast-forward this without invoking rebase */
-				opt_ff = "--ff-only";
-				ran_ff = 1;
-				ret = run_merge();
-			}
-			free_commit_list(list);
-		}
-		if (!ran_ff)
-			ret = run_rebase(&curr_head, merge_heads.oid, &rebase_fork_point);
-
-		if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
-			     recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
-			ret = rebase_submodules();
-
-		return ret;
-	} else {
-		int ret = run_merge();
-		if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
-			     recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))
-			ret = update_submodules();
-		return ret;
-	}
-}