/src/git/builtin/submodule--helper.c

Source (jump to first uncovered line)
#include "builtin.h"
#include "abspath.h"
#include "environment.h"
#include "gettext.h"
#include "hex.h"
#include "repository.h"
#include "config.h"
#include "parse-options.h"
#include "quote.h"
#include "path.h"
#include "pathspec.h"
#include "preload-index.h"
#include "dir.h"
#include "read-cache.h"
#include "setup.h"
#include "sparse-index.h"
#include "submodule.h"
#include "submodule-config.h"
#include "string-list.h"
#include "run-command.h"
#include "remote.h"
#include "refs.h"
#include "refspec.h"
#include "revision.h"
#include "diffcore.h"
#include "diff.h"
#include "object-file.h"
#include "object-name.h"
#include "object-store-ll.h"
#include "advice.h"
#include "branch.h"
#include "list-objects-filter-options.h"

#define OPT_QUIET (1 << 0)
#define OPT_CACHED (1 << 1)
#define OPT_RECURSIVE (1 << 2)
#define OPT_FORCE (1 << 3)

typedef void (*each_submodule_fn)(const struct cache_entry *list_item,
          void *cb_data);

static int repo_get_default_remote(struct repository *repo, char **default_remote)
{
  char *dest = NULL;
  struct strbuf sb = STRBUF_INIT;
  struct ref_store *store = get_main_ref_store(repo);
  const char *refname = refs_resolve_ref_unsafe(store, "HEAD", 0, NULL,
                  NULL);

  if (!refname)
    return die_message(_("No such ref: %s"), "HEAD");

  /* detached HEAD */
  if (!strcmp(refname, "HEAD")) {
    *default_remote = xstrdup("origin");
    return 0;
  }

  if (!skip_prefix(refname, "refs/heads/", &refname))
    return die_message(_("Expecting a full ref name, got %s"),
           refname);

  strbuf_addf(&sb, "branch.%s.remote", refname);
  if (repo_config_get_string(repo, sb.buf, &dest))
    *default_remote = xstrdup("origin");
  else
    *default_remote = dest;

  strbuf_release(&sb);
  return 0;
}

static int get_default_remote_submodule(const char *module_path, char **default_remote)
{
  struct repository subrepo;
  int ret;

  if (repo_submodule_init(&subrepo, the_repository, module_path,
        null_oid()) < 0)
    return die_message(_("could not get a repository handle for submodule '%s'"),
           module_path);
  ret = repo_get_default_remote(&subrepo, default_remote);
  repo_clear(&subrepo);

  return ret;
}

static char *get_default_remote(void)
{
  char *default_remote;
  int code = repo_get_default_remote(the_repository, &default_remote);

  if (code)
    exit(code);

  return default_remote;
}

static char *resolve_relative_url(const char *rel_url, const char *up_path, int quiet)
{
  char *remoteurl, *resolved_url;
  char *remote = get_default_remote();
  struct strbuf remotesb = STRBUF_INIT;

  strbuf_addf(&remotesb, "remote.%s.url", remote);
  if (git_config_get_string(remotesb.buf, &remoteurl)) {
    if (!quiet)
      warning(_("could not look up configuration '%s'. "
          "Assuming this repository is its own "
          "authoritative upstream."),
        remotesb.buf);
    remoteurl = xgetcwd();
  }
  resolved_url = relative_url(remoteurl, rel_url, up_path);

  free(remote);
  free(remoteurl);
  strbuf_release(&remotesb);

  return resolved_url;
}

/* the result should be freed by the caller. */
static char *get_submodule_displaypath(const char *path, const char *prefix,
               const char *super_prefix)
{
  if (prefix && super_prefix) {
    BUG("cannot have prefix '%s' and superprefix '%s'",
        prefix, super_prefix);
  } else if (prefix) {
    struct strbuf sb = STRBUF_INIT;
    char *displaypath = xstrdup(relative_path(path, prefix, &sb));
    strbuf_release(&sb);
    return displaypath;
  } else if (super_prefix) {
    return xstrfmt("%s%s", super_prefix, path);
  } else {
    return xstrdup(path);
  }
}

static char *compute_rev_name(const char *sub_path, const char* object_id)
{
  struct strbuf sb = STRBUF_INIT;
  const char ***d;

  static const char *describe_bare[] = { NULL };

  static const char *describe_tags[] = { "--tags", NULL };

  static const char *describe_contains[] = { "--contains", NULL };

  static const char *describe_all_always[] = { "--all", "--always", NULL };

  static const char **describe_argv[] = { describe_bare, describe_tags,
            describe_contains,
            describe_all_always, NULL };

  for (d = describe_argv; *d; d++) {
    struct child_process cp = CHILD_PROCESS_INIT;
    prepare_submodule_repo_env(&cp.env);
    cp.dir = sub_path;
    cp.git_cmd = 1;
    cp.no_stderr = 1;

    strvec_push(&cp.args, "describe");
    strvec_pushv(&cp.args, *d);
    strvec_push(&cp.args, object_id);

    if (!capture_command(&cp, &sb, 0)) {
      strbuf_strip_suffix(&sb, "\n");
      return strbuf_detach(&sb, NULL);
    }
  }

  strbuf_release(&sb);
  return NULL;
}

struct module_list {
  const struct cache_entry **entries;
  int alloc, nr;
};
#define MODULE_LIST_INIT { 0 }

static void module_list_release(struct module_list *ml)
{
  free(ml->entries);
}

static int module_list_compute(const char **argv,
             const char *prefix,
             struct pathspec *pathspec,
             struct module_list *list)
{
  int i, result = 0;
  char *ps_matched = NULL;

  parse_pathspec(pathspec, 0,
           PATHSPEC_PREFER_FULL,
           prefix, argv);

  if (pathspec->nr)
    ps_matched = xcalloc(pathspec->nr, 1);

  if (repo_read_index(the_repository) < 0)
    die(_("index file corrupt"));

  for (i = 0; i < the_repository->index->cache_nr; i++) {
    const struct cache_entry *ce = the_repository->index->cache[i];

    if (!match_pathspec(the_repository->index, pathspec, ce->name, ce_namelen(ce),
            0, ps_matched, 1) ||
        !S_ISGITLINK(ce->ce_mode))
      continue;

    ALLOC_GROW(list->entries, list->nr + 1, list->alloc);
    list->entries[list->nr++] = ce;
    while (i + 1 < the_repository->index->cache_nr &&
           !strcmp(ce->name, the_repository->index->cache[i + 1]->name))
      /*
       * Skip entries with the same name in different stages
       * to make sure an entry is returned only once.
       */
      i++;
  }

  if (ps_matched && report_path_error(ps_matched, pathspec))
    result = -1;

  free(ps_matched);

  return result;
}

static void module_list_active(struct module_list *list)
{
  int i;
  struct module_list active_modules = MODULE_LIST_INIT;

  for (i = 0; i < list->nr; i++) {
    const struct cache_entry *ce = list->entries[i];

    if (!is_submodule_active(the_repository, ce->name))
      continue;

    ALLOC_GROW(active_modules.entries,
         active_modules.nr + 1,
         active_modules.alloc);
    active_modules.entries[active_modules.nr++] = ce;
  }

  module_list_release(list);
  *list = active_modules;
}

static char *get_up_path(const char *path)
{
  struct strbuf sb = STRBUF_INIT;

  strbuf_addstrings(&sb, "../", count_slashes(path));

  /*
   * Check if 'path' ends with slash or not
   * for having the same output for dir/sub_dir
   * and dir/sub_dir/
   */
  if (!is_dir_sep(path[strlen(path) - 1]))
    strbuf_addstr(&sb, "../");

  return strbuf_detach(&sb, NULL);
}

static void for_each_listed_submodule(const struct module_list *list,
              each_submodule_fn fn, void *cb_data)
{
  int i;

  for (i = 0; i < list->nr; i++)
    fn(list->entries[i], cb_data);
}

struct foreach_cb {
  int argc;
  const char **argv;
  const char *prefix;
  const char *super_prefix;
  int quiet;
  int recursive;
};
#define FOREACH_CB_INIT { 0 }

static void runcommand_in_submodule_cb(const struct cache_entry *list_item,
               void *cb_data)
{
  struct foreach_cb *info = cb_data;
  const char *path = list_item->name;
  const struct object_id *ce_oid = &list_item->oid;
  const struct submodule *sub;
  struct child_process cp = CHILD_PROCESS_INIT;
  char *displaypath;

  if (validate_submodule_path(path) < 0)
    exit(128);

  displaypath = get_submodule_displaypath(path, info->prefix,
            info->super_prefix);

  sub = submodule_from_path(the_repository, null_oid(), path);

  if (!sub)
    die(_("No url found for submodule path '%s' in .gitmodules"),
      displaypath);

  if (!is_submodule_populated_gently(path, NULL))
    goto cleanup;

  prepare_submodule_repo_env(&cp.env);

  /*
   * For the purpose of executing <command> in the submodule,
   * separate shell is used for the purpose of running the
   * child process.
   */
  cp.use_shell = 1;
  cp.dir = path;

  /*
   * NEEDSWORK: the command currently has access to the variables $name,
   * $sm_path, $displaypath, $sha1 and $toplevel only when the command
   * contains a single argument. This is done for maintaining a faithful
   * translation from shell script.
   */
  if (info->argc == 1) {
    char *toplevel = xgetcwd();
    struct strbuf sb = STRBUF_INIT;

    strvec_pushf(&cp.env, "name=%s", sub->name);
    strvec_pushf(&cp.env, "sm_path=%s", path);
    strvec_pushf(&cp.env, "displaypath=%s", displaypath);
    strvec_pushf(&cp.env, "sha1=%s",
           oid_to_hex(ce_oid));
    strvec_pushf(&cp.env, "toplevel=%s", toplevel);

    /*
     * Since the path variable was accessible from the script
     * before porting, it is also made available after porting.
     * The environment variable "PATH" has a very special purpose
     * on windows. And since environment variables are
     * case-insensitive in windows, it interferes with the
     * existing PATH variable. Hence, to avoid that, we expose
     * path via the args strvec and not via env.
     */
    sq_quote_buf(&sb, path);
    strvec_pushf(&cp.args, "path=%s; %s",
           sb.buf, info->argv[0]);
    strbuf_release(&sb);
    free(toplevel);
  } else {
    strvec_pushv(&cp.args, info->argv);
  }

  if (!info->quiet)
    printf(_("Entering '%s'\n"), displaypath);

  if (info->argv[0] && run_command(&cp))
    die(_("run_command returned non-zero status for %s\n."),
      displaypath);

  if (info->recursive) {
    struct child_process cpr = CHILD_PROCESS_INIT;

    cpr.git_cmd = 1;
    cpr.dir = path;
    prepare_submodule_repo_env(&cpr.env);

    strvec_pushl(&cpr.args, "submodule--helper", "foreach", "--recursive",
           NULL);
    strvec_pushf(&cpr.args, "--super-prefix=%s/", displaypath);

    if (info->quiet)
      strvec_push(&cpr.args, "--quiet");

    strvec_push(&cpr.args, "--");
    strvec_pushv(&cpr.args, info->argv);

    if (run_command(&cpr))
      die(_("run_command returned non-zero status while "
        "recursing in the nested submodules of %s\n."),
        displaypath);
  }

cleanup:
  free(displaypath);
}

static int module_foreach(int argc, const char **argv, const char *prefix)
{
  struct foreach_cb info = FOREACH_CB_INIT;
  struct pathspec pathspec = { 0 };
  struct module_list list = MODULE_LIST_INIT;
  struct option module_foreach_options[] = {
    OPT__SUPER_PREFIX(&info.super_prefix),
    OPT__QUIET(&info.quiet, N_("suppress output of entering each submodule command")),
    OPT_BOOL(0, "recursive", &info.recursive,
       N_("recurse into nested submodules")),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule foreach [--quiet] [--recursive] [--] <command>"),
    NULL
  };
  int ret = 1;

  argc = parse_options(argc, argv, prefix, module_foreach_options,
           git_submodule_helper_usage, 0);

  if (module_list_compute(NULL, prefix, &pathspec, &list) < 0)
    goto cleanup;

  info.argc = argc;
  info.argv = argv;
  info.prefix = prefix;

  for_each_listed_submodule(&list, runcommand_in_submodule_cb, &info);

  ret = 0;
cleanup:
  module_list_release(&list);
  clear_pathspec(&pathspec);
  return ret;
}

static int starts_with_dot_slash(const char *const path)
{
  return path_match_flags(path, PATH_MATCH_STARTS_WITH_DOT_SLASH |
        PATH_MATCH_XPLATFORM);
}

static int starts_with_dot_dot_slash(const char *const path)
{
  return path_match_flags(path, PATH_MATCH_STARTS_WITH_DOT_DOT_SLASH |
        PATH_MATCH_XPLATFORM);
}

struct init_cb {
  const char *prefix;
  const char *super_prefix;
  unsigned int flags;
};
#define INIT_CB_INIT { 0 }

static void init_submodule(const char *path, const char *prefix,
         const char *super_prefix,
         unsigned int flags)
{
  const struct submodule *sub;
  struct strbuf sb = STRBUF_INIT;
  const char *upd;
  char *url = NULL, *displaypath;

  displaypath = get_submodule_displaypath(path, prefix, super_prefix);

  sub = submodule_from_path(the_repository, null_oid(), path);

  if (!sub)
    die(_("No url found for submodule path '%s' in .gitmodules"),
      displaypath);

  /*
   * NEEDSWORK: In a multi-working-tree world, this needs to be
   * set in the per-worktree config.
   *
   * Set active flag for the submodule being initialized
   */
  if (!is_submodule_active(the_repository, path)) {
    strbuf_addf(&sb, "submodule.%s.active", sub->name);
    git_config_set_gently(sb.buf, "true");
    strbuf_reset(&sb);
  }

  /*
   * Copy url setting when it is not set yet.
   * To look up the url in .git/config, we must not fall back to
   * .gitmodules, so look it up directly.
   */
  strbuf_addf(&sb, "submodule.%s.url", sub->name);
  if (git_config_get_string(sb.buf, &url)) {
    if (!sub->url)
      die(_("No url found for submodule path '%s' in .gitmodules"),
        displaypath);

    url = xstrdup(sub->url);

    /* Possibly a url relative to parent */
    if (starts_with_dot_dot_slash(url) ||
        starts_with_dot_slash(url)) {
      char *oldurl = url;

      url = resolve_relative_url(oldurl, NULL, 0);
      free(oldurl);
    }

    if (git_config_set_gently(sb.buf, url))
      die(_("Failed to register url for submodule path '%s'"),
          displaypath);
    if (!(flags & OPT_QUIET))
      fprintf(stderr,
        _("Submodule '%s' (%s) registered for path '%s'\n"),
        sub->name, url, displaypath);
  }
  strbuf_reset(&sb);

  /* Copy "update" setting when it is not set yet */
  strbuf_addf(&sb, "submodule.%s.update", sub->name);
  if (git_config_get_string_tmp(sb.buf, &upd) &&
      sub->update_strategy.type != SM_UPDATE_UNSPECIFIED) {
    if (sub->update_strategy.type == SM_UPDATE_COMMAND) {
      fprintf(stderr, _("warning: command update mode suggested for submodule '%s'\n"),
        sub->name);
      upd = "none";
    } else {
      upd = submodule_update_type_to_string(sub->update_strategy.type);
    }

    if (git_config_set_gently(sb.buf, upd))
      die(_("Failed to register update mode for submodule path '%s'"), displaypath);
  }
  strbuf_release(&sb);
  free(displaypath);
  free(url);
}

static void init_submodule_cb(const struct cache_entry *list_item, void *cb_data)
{
  struct init_cb *info = cb_data;

  init_submodule(list_item->name, info->prefix, info->super_prefix,
           info->flags);
}

static int module_init(int argc, const char **argv, const char *prefix)
{
  struct init_cb info = INIT_CB_INIT;
  struct pathspec pathspec = { 0 };
  struct module_list list = MODULE_LIST_INIT;
  int quiet = 0;
  struct option module_init_options[] = {
    OPT__QUIET(&quiet, N_("suppress output for initializing a submodule")),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule init [<options>] [<path>]"),
    NULL
  };
  int ret = 1;

  argc = parse_options(argc, argv, prefix, module_init_options,
           git_submodule_helper_usage, 0);

  if (module_list_compute(argv, prefix, &pathspec, &list) < 0)
    goto cleanup;

  /*
   * If there are no path args and submodule.active is set then,
   * by default, only initialize 'active' modules.
   */
  if (!argc && !git_config_get("submodule.active"))
    module_list_active(&list);

  info.prefix = prefix;
  if (quiet)
    info.flags |= OPT_QUIET;

  for_each_listed_submodule(&list, init_submodule_cb, &info);

  ret = 0;
cleanup:
  module_list_release(&list);
  clear_pathspec(&pathspec);
  return ret;
}

struct status_cb {
  const char *prefix;
  const char *super_prefix;
  unsigned int flags;
};
#define STATUS_CB_INIT { 0 }

static void print_status(unsigned int flags, char state, const char *path,
       const struct object_id *oid, const char *displaypath)
{
  if (flags & OPT_QUIET)
    return;

  printf("%c%s %s", state, oid_to_hex(oid), displaypath);

  if (state == ' ' || state == '+') {
    char *name = compute_rev_name(path, oid_to_hex(oid));

    if (name)
      printf(" (%s)", name);
    free(name);
  }

  printf("\n");
}

static int handle_submodule_head_ref(const char *refname UNUSED,
             const char *referent UNUSED,
             const struct object_id *oid,
             int flags UNUSED,
             void *cb_data)
{
  struct object_id *output = cb_data;

  if (oid)
    oidcpy(output, oid);

  return 0;
}

static void status_submodule(const char *path, const struct object_id *ce_oid,
           unsigned int ce_flags, const char *prefix,
           const char *super_prefix, unsigned int flags)
{
  char *displaypath;
  struct strvec diff_files_args = STRVEC_INIT;
  struct rev_info rev = REV_INFO_INIT;
  struct strbuf buf = STRBUF_INIT;
  const char *git_dir;
  struct setup_revision_opt opt = {
    .free_removed_argv_elements = 1,
  };

  if (validate_submodule_path(path) < 0)
    exit(128);

  if (!submodule_from_path(the_repository, null_oid(), path))
    die(_("no submodule mapping found in .gitmodules for path '%s'"),
          path);

  displaypath = get_submodule_displaypath(path, prefix, super_prefix);

  if ((CE_STAGEMASK & ce_flags) >> CE_STAGESHIFT) {
    print_status(flags, 'U', path, null_oid(), displaypath);
    goto cleanup;
  }

  strbuf_addf(&buf, "%s/.git", path);
  git_dir = read_gitfile(buf.buf);
  if (!git_dir)
    git_dir = buf.buf;

  if (!is_submodule_active(the_repository, path) ||
      !is_git_directory(git_dir)) {
    print_status(flags, '-', path, ce_oid, displaypath);
    strbuf_release(&buf);
    goto cleanup;
  }
  strbuf_release(&buf);

  strvec_pushl(&diff_files_args, "diff-files",
         "--ignore-submodules=dirty", "--quiet", "--",
         path, NULL);

  git_config(git_diff_basic_config, NULL);

  repo_init_revisions(the_repository, &rev, NULL);
  rev.abbrev = 0;
  setup_revisions(diff_files_args.nr, diff_files_args.v, &rev, &opt);
  run_diff_files(&rev, 0);

  if (!diff_result_code(&rev)) {
    print_status(flags, ' ', path, ce_oid,
           displaypath);
  } else if (!(flags & OPT_CACHED)) {
    struct object_id oid;
    struct ref_store *refs = repo_get_submodule_ref_store(the_repository,
                      path);

    if (!refs) {
      print_status(flags, '-', path, ce_oid, displaypath);
      goto cleanup;
    }
    if (refs_head_ref(refs, handle_submodule_head_ref, &oid))
      die(_("could not resolve HEAD ref inside the "
            "submodule '%s'"), path);

    print_status(flags, '+', path, &oid, displaypath);
  } else {
    print_status(flags, '+', path, ce_oid, displaypath);
  }

  if (flags & OPT_RECURSIVE) {
    struct child_process cpr = CHILD_PROCESS_INIT;

    cpr.git_cmd = 1;
    cpr.dir = path;
    prepare_submodule_repo_env(&cpr.env);

    strvec_pushl(&cpr.args, "submodule--helper", "status",
           "--recursive", NULL);
    strvec_pushf(&cpr.args, "--super-prefix=%s/", displaypath);

    if (flags & OPT_CACHED)
      strvec_push(&cpr.args, "--cached");

    if (flags & OPT_QUIET)
      strvec_push(&cpr.args, "--quiet");

    if (run_command(&cpr))
      die(_("failed to recurse into submodule '%s'"), path);
  }

cleanup:
  strvec_clear(&diff_files_args);
  free(displaypath);
  release_revisions(&rev);
}

static void status_submodule_cb(const struct cache_entry *list_item,
        void *cb_data)
{
  struct status_cb *info = cb_data;

  status_submodule(list_item->name, &list_item->oid, list_item->ce_flags,
       info->prefix, info->super_prefix, info->flags);
}

static int module_status(int argc, const char **argv, const char *prefix)
{
  struct status_cb info = STATUS_CB_INIT;
  struct pathspec pathspec = { 0 };
  struct module_list list = MODULE_LIST_INIT;
  int quiet = 0;
  struct option module_status_options[] = {
    OPT__SUPER_PREFIX(&info.super_prefix),
    OPT__QUIET(&quiet, N_("suppress submodule status output")),
    OPT_BIT(0, "cached", &info.flags, N_("use commit stored in the index instead of the one stored in the submodule HEAD"), OPT_CACHED),
    OPT_BIT(0, "recursive", &info.flags, N_("recurse into nested submodules"), OPT_RECURSIVE),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule status [--quiet] [--cached] [--recursive] [<path>...]"),
    NULL
  };
  int ret = 1;

  argc = parse_options(argc, argv, prefix, module_status_options,
           git_submodule_helper_usage, 0);

  if (module_list_compute(argv, prefix, &pathspec, &list) < 0)
    goto cleanup;

  info.prefix = prefix;
  if (quiet)
    info.flags |= OPT_QUIET;

  for_each_listed_submodule(&list, status_submodule_cb, &info);

  ret = 0;
cleanup:
  module_list_release(&list);
  clear_pathspec(&pathspec);
  return ret;
}

struct module_cb {
  unsigned int mod_src;
  unsigned int mod_dst;
  struct object_id oid_src;
  struct object_id oid_dst;
  char status;
  char *sm_path;
};
#define MODULE_CB_INIT { 0 }

static void module_cb_release(struct module_cb *mcb)
{
  free(mcb->sm_path);
}

struct module_cb_list {
  struct module_cb **entries;
  int alloc, nr;
};
#define MODULE_CB_LIST_INIT { 0 }

static void module_cb_list_release(struct module_cb_list *mcbl)
{
  int i;

  for (i = 0; i < mcbl->nr; i++) {
    struct module_cb *mcb = mcbl->entries[i];

    module_cb_release(mcb);
    free(mcb);
  }
  free(mcbl->entries);
}

struct summary_cb {
  int argc;
  const char **argv;
  const char *prefix;
  const char *super_prefix;
  unsigned int cached: 1;
  unsigned int for_status: 1;
  unsigned int files: 1;
  int summary_limit;
};
#define SUMMARY_CB_INIT { 0 }

enum diff_cmd {
  DIFF_INDEX,
  DIFF_FILES
};

static char *verify_submodule_committish(const char *sm_path,
           const char *committish)
{
  struct child_process cp_rev_parse = CHILD_PROCESS_INIT;
  struct strbuf result = STRBUF_INIT;

  cp_rev_parse.git_cmd = 1;
  cp_rev_parse.dir = sm_path;
  prepare_submodule_repo_env(&cp_rev_parse.env);
  strvec_pushl(&cp_rev_parse.args, "rev-parse", "-q", "--short", NULL);
  strvec_pushf(&cp_rev_parse.args, "%s^0", committish);
  strvec_push(&cp_rev_parse.args, "--");

  if (capture_command(&cp_rev_parse, &result, 0))
    return NULL;

  strbuf_trim_trailing_newline(&result);
  return strbuf_detach(&result, NULL);
}

static void print_submodule_summary(struct summary_cb *info, const char *errmsg,
            int total_commits, const char *displaypath,
            const char *src_abbrev, const char *dst_abbrev,
            struct module_cb *p)
{
  if (p->status == 'T') {
    if (S_ISGITLINK(p->mod_dst))
      printf(_("* %s %s(blob)->%s(submodule)"),
         displaypath, src_abbrev, dst_abbrev);
    else
      printf(_("* %s %s(submodule)->%s(blob)"),
         displaypath, src_abbrev, dst_abbrev);
  } else {
    printf("* %s %s...%s",
      displaypath, src_abbrev, dst_abbrev);
  }

  if (total_commits < 0)
    printf(":\n");
  else
    printf(" (%d):\n", total_commits);

  if (errmsg) {
    printf(_("%s"), errmsg);
  } else if (total_commits > 0) {
    struct child_process cp_log = CHILD_PROCESS_INIT;

    cp_log.git_cmd = 1;
    cp_log.dir = p->sm_path;
    prepare_submodule_repo_env(&cp_log.env);
    strvec_pushl(&cp_log.args, "log", NULL);

    if (S_ISGITLINK(p->mod_src) && S_ISGITLINK(p->mod_dst)) {
      if (info->summary_limit > 0)
        strvec_pushf(&cp_log.args, "-%d",
               info->summary_limit);

      strvec_pushl(&cp_log.args, "--pretty=  %m %s",
             "--first-parent", NULL);
      strvec_pushf(&cp_log.args, "%s...%s",
             src_abbrev, dst_abbrev);
    } else if (S_ISGITLINK(p->mod_dst)) {
      strvec_pushl(&cp_log.args, "--pretty=  > %s",
             "-1", dst_abbrev, NULL);
    } else {
      strvec_pushl(&cp_log.args, "--pretty=  < %s",
             "-1", src_abbrev, NULL);
    }
    run_command(&cp_log);
  }
  printf("\n");
}

static void generate_submodule_summary(struct summary_cb *info,
               struct module_cb *p)
{
  char *displaypath, *src_abbrev = NULL, *dst_abbrev;
  int missing_src = 0, missing_dst = 0;
  struct strbuf errmsg = STRBUF_INIT;
  int total_commits = -1;

  if (!info->cached && oideq(&p->oid_dst, null_oid())) {
    if (S_ISGITLINK(p->mod_dst)) {
      struct ref_store *refs = repo_get_submodule_ref_store(the_repository,
                        p->sm_path);

      if (refs)
        refs_head_ref(refs, handle_submodule_head_ref, &p->oid_dst);
    } else if (S_ISLNK(p->mod_dst) || S_ISREG(p->mod_dst)) {
      struct stat st;
      int fd = open(p->sm_path, O_RDONLY);

      if (fd < 0 || fstat(fd, &st) < 0 ||
          index_fd(the_repository->index, &p->oid_dst, fd, &st, OBJ_BLOB,
             p->sm_path, 0))
        error(_("couldn't hash object from '%s'"), p->sm_path);
    } else {
      /* for a submodule removal (mode:0000000), don't warn */
      if (p->mod_dst)
        warning(_("unexpected mode %o"), p->mod_dst);
    }
  }

  if (S_ISGITLINK(p->mod_src)) {
    if (p->status != 'D')
      src_abbrev = verify_submodule_committish(p->sm_path,
                 oid_to_hex(&p->oid_src));
    if (!src_abbrev) {
      missing_src = 1;
      /*
       * As `rev-parse` failed, we fallback to getting
       * the abbreviated hash using oid_src. We do
       * this as we might still need the abbreviated
       * hash in cases like a submodule type change, etc.
       */
      src_abbrev = xstrndup(oid_to_hex(&p->oid_src), 7);
    }
  } else {
    /*
     * The source does not point to a submodule.
     * So, we fallback to getting the abbreviation using
     * oid_src as we might still need the abbreviated
     * hash in cases like submodule add, etc.
     */
    src_abbrev = xstrndup(oid_to_hex(&p->oid_src), 7);
  }

  if (S_ISGITLINK(p->mod_dst)) {
    dst_abbrev = verify_submodule_committish(p->sm_path,
               oid_to_hex(&p->oid_dst));
    if (!dst_abbrev) {
      missing_dst = 1;
      /*
       * As `rev-parse` failed, we fallback to getting
       * the abbreviated hash using oid_dst. We do
       * this as we might still need the abbreviated
       * hash in cases like a submodule type change, etc.
       */
      dst_abbrev = xstrndup(oid_to_hex(&p->oid_dst), 7);
    }
  } else {
    /*
     * The destination does not point to a submodule.
     * So, we fallback to getting the abbreviation using
     * oid_dst as we might still need the abbreviated
     * hash in cases like a submodule removal, etc.
     */
    dst_abbrev = xstrndup(oid_to_hex(&p->oid_dst), 7);
  }

  displaypath = get_submodule_displaypath(p->sm_path, info->prefix,
            info->super_prefix);

  if (!missing_src && !missing_dst) {
    struct child_process cp_rev_list = CHILD_PROCESS_INIT;
    struct strbuf sb_rev_list = STRBUF_INIT;

    strvec_pushl(&cp_rev_list.args, "rev-list",
           "--first-parent", "--count", NULL);
    if (S_ISGITLINK(p->mod_src) && S_ISGITLINK(p->mod_dst))
      strvec_pushf(&cp_rev_list.args, "%s...%s",
             src_abbrev, dst_abbrev);
    else
      strvec_push(&cp_rev_list.args, S_ISGITLINK(p->mod_src) ?
            src_abbrev : dst_abbrev);
    strvec_push(&cp_rev_list.args, "--");

    cp_rev_list.git_cmd = 1;
    cp_rev_list.dir = p->sm_path;
    prepare_submodule_repo_env(&cp_rev_list.env);

    if (!capture_command(&cp_rev_list, &sb_rev_list, 0))
      total_commits = atoi(sb_rev_list.buf);

    strbuf_release(&sb_rev_list);
  } else {
    /*
     * Don't give error msg for modification whose dst is not
     * submodule, i.e., deleted or changed to blob
     */
    if (S_ISGITLINK(p->mod_dst)) {
      if (missing_src && missing_dst) {
        strbuf_addf(&errmsg, "  Warn: %s doesn't contain commits %s and %s\n",
              displaypath, oid_to_hex(&p->oid_src),
              oid_to_hex(&p->oid_dst));
      } else {
        strbuf_addf(&errmsg, "  Warn: %s doesn't contain commit %s\n",
              displaypath, missing_src ?
              oid_to_hex(&p->oid_src) :
              oid_to_hex(&p->oid_dst));
      }
    }
  }

  print_submodule_summary(info, errmsg.len ? errmsg.buf : NULL,
        total_commits, displaypath, src_abbrev,
        dst_abbrev, p);

  free(displaypath);
  free(src_abbrev);
  free(dst_abbrev);
  strbuf_release(&errmsg);
}

static void prepare_submodule_summary(struct summary_cb *info,
              struct module_cb_list *list)
{
  int i;
  for (i = 0; i < list->nr; i++) {
    const struct submodule *sub;
    struct module_cb *p = list->entries[i];
    struct strbuf sm_gitdir = STRBUF_INIT;

    if (p->status == 'D' || p->status == 'T') {
      generate_submodule_summary(info, p);
      continue;
    }

    if (info->for_status && p->status != 'A' &&
        (sub = submodule_from_path(the_repository,
                 null_oid(), p->sm_path))) {
      char *config_key = NULL;
      const char *value;
      int ignore_all = 0;

      config_key = xstrfmt("submodule.%s.ignore",
               sub->name);
      if (!git_config_get_string_tmp(config_key, &value))
        ignore_all = !strcmp(value, "all");
      else if (sub->ignore)
        ignore_all = !strcmp(sub->ignore, "all");

      free(config_key);
      if (ignore_all)
        continue;
    }

    /* Also show added or modified modules which are checked out */
    strbuf_addstr(&sm_gitdir, p->sm_path);
    if (is_nonbare_repository_dir(&sm_gitdir))
      generate_submodule_summary(info, p);
    strbuf_release(&sm_gitdir);
  }
}

static void submodule_summary_callback(struct diff_queue_struct *q,
               struct diff_options *options UNUSED,
               void *data)
{
  int i;
  struct module_cb_list *list = data;
  for (i = 0; i < q->nr; i++) {
    struct diff_filepair *p = q->queue[i];
    struct module_cb *temp;

    if (!S_ISGITLINK(p->one->mode) && !S_ISGITLINK(p->two->mode))
      continue;
    temp = (struct module_cb*)malloc(sizeof(struct module_cb));
    temp->mod_src = p->one->mode;
    temp->mod_dst = p->two->mode;
    temp->oid_src = p->one->oid;
    temp->oid_dst = p->two->oid;
    temp->status = p->status;
    temp->sm_path = xstrdup(p->one->path);

    ALLOC_GROW(list->entries, list->nr + 1, list->alloc);
    list->entries[list->nr++] = temp;
  }
}

static const char *get_diff_cmd(enum diff_cmd diff_cmd)
{
  switch (diff_cmd) {
  case DIFF_INDEX: return "diff-index";
  case DIFF_FILES: return "diff-files";
  default: BUG("bad diff_cmd value %d", diff_cmd);
  }
}

static int compute_summary_module_list(struct object_id *head_oid,
               struct summary_cb *info,
               enum diff_cmd diff_cmd)
{
  struct strvec diff_args = STRVEC_INIT;
  struct rev_info rev;
  struct setup_revision_opt opt = {
    .free_removed_argv_elements = 1,
  };
  struct module_cb_list list = MODULE_CB_LIST_INIT;
  int ret = 0;

  strvec_push(&diff_args, get_diff_cmd(diff_cmd));
  if (info->cached)
    strvec_push(&diff_args, "--cached");
  strvec_pushl(&diff_args, "--ignore-submodules=dirty", "--raw", NULL);
  if (head_oid)
    strvec_push(&diff_args, oid_to_hex(head_oid));
  strvec_push(&diff_args, "--");
  if (info->argc)
    strvec_pushv(&diff_args, info->argv);

  git_config(git_diff_basic_config, NULL);
  repo_init_revisions(the_repository, &rev, info->prefix);
  rev.abbrev = 0;
  precompose_argv_prefix(diff_args.nr, diff_args.v, NULL);
  setup_revisions(diff_args.nr, diff_args.v, &rev, &opt);
  rev.diffopt.output_format = DIFF_FORMAT_NO_OUTPUT | DIFF_FORMAT_CALLBACK;
  rev.diffopt.format_callback = submodule_summary_callback;
  rev.diffopt.format_callback_data = &list;

  if (!info->cached) {
    if (diff_cmd == DIFF_INDEX)
      setup_work_tree();
    if (repo_read_index_preload(the_repository, &rev.diffopt.pathspec, 0) < 0) {
      perror("repo_read_index_preload");
      ret = -1;
      goto cleanup;
    }
  } else if (repo_read_index(the_repository) < 0) {
    perror("repo_read_cache");
    ret = -1;
    goto cleanup;
  }

  if (diff_cmd == DIFF_INDEX)
    run_diff_index(&rev, info->cached ? DIFF_INDEX_CACHED : 0);
  else
    run_diff_files(&rev, 0);
  prepare_submodule_summary(info, &list);
cleanup:
  strvec_clear(&diff_args);
  release_revisions(&rev);
  module_cb_list_release(&list);
  return ret;
}

static int module_summary(int argc, const char **argv, const char *prefix)
{
  struct summary_cb info = SUMMARY_CB_INIT;
  int cached = 0;
  int for_status = 0;
  int files = 0;
  int summary_limit = -1;
  enum diff_cmd diff_cmd = DIFF_INDEX;
  struct object_id head_oid;
  int ret;
  struct option module_summary_options[] = {
    OPT_BOOL(0, "cached", &cached,
       N_("use the commit stored in the index instead of the submodule HEAD")),
    OPT_BOOL(0, "files", &files,
       N_("compare the commit in the index with that in the submodule HEAD")),
    OPT_BOOL(0, "for-status", &for_status,
       N_("skip submodules with 'ignore_config' value set to 'all'")),
    OPT_INTEGER('n', "summary-limit", &summary_limit,
           N_("limit the summary size")),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule summary [<options>] [<commit>] [--] [<path>]"),
    NULL
  };

  argc = parse_options(argc, argv, prefix, module_summary_options,
           git_submodule_helper_usage, 0);

  if (!summary_limit)
    return 0;

  if (!repo_get_oid(the_repository, argc ? argv[0] : "HEAD", &head_oid)) {
    if (argc) {
      argv++;
      argc--;
    }
  } else if (!argc || !strcmp(argv[0], "HEAD")) {
    /* before the first commit: compare with an empty tree */
    oidcpy(&head_oid, the_hash_algo->empty_tree);
    if (argc) {
      argv++;
      argc--;
    }
  } else {
    if (repo_get_oid(the_repository, "HEAD", &head_oid))
      die(_("could not fetch a revision for HEAD"));
  }

  if (files) {
    if (cached)
      die(_("options '%s' and '%s' cannot be used together"), "--cached", "--files");
    diff_cmd = DIFF_FILES;
  }

  info.argc = argc;
  info.argv = argv;
  info.prefix = prefix;
  info.cached = !!cached;
  info.files = !!files;
  info.for_status = !!for_status;
  info.summary_limit = summary_limit;

  ret = compute_summary_module_list((diff_cmd == DIFF_INDEX) ? &head_oid : NULL,
            &info, diff_cmd);
  return ret;
}

struct sync_cb {
  const char *prefix;
  const char *super_prefix;
  unsigned int flags;
};
#define SYNC_CB_INIT { 0 }

static void sync_submodule(const char *path, const char *prefix,
         const char *super_prefix, unsigned int flags)
{
  const struct submodule *sub;
  char *remote_key = NULL;
  char *sub_origin_url, *super_config_url, *displaypath, *default_remote;
  struct strbuf sb = STRBUF_INIT;
  char *sub_config_path = NULL;
  int code;

  if (!is_submodule_active(the_repository, path))
    return;

  if (validate_submodule_path(path) < 0)
    exit(128);

  sub = submodule_from_path(the_repository, null_oid(), path);

  if (sub && sub->url) {
    if (starts_with_dot_dot_slash(sub->url) ||
        starts_with_dot_slash(sub->url)) {
      char *up_path = get_up_path(path);

      sub_origin_url = resolve_relative_url(sub->url, up_path, 1);
      super_config_url = resolve_relative_url(sub->url, NULL, 1);
      free(up_path);
    } else {
      sub_origin_url = xstrdup(sub->url);
      super_config_url = xstrdup(sub->url);
    }
  } else {
    sub_origin_url = xstrdup("");
    super_config_url = xstrdup("");
  }

  displaypath = get_submodule_displaypath(path, prefix, super_prefix);

  if (!(flags & OPT_QUIET))
    printf(_("Synchronizing submodule url for '%s'\n"),
       displaypath);

  strbuf_reset(&sb);
  strbuf_addf(&sb, "submodule.%s.url", sub->name);
  if (git_config_set_gently(sb.buf, super_config_url))
    die(_("failed to register url for submodule path '%s'"),
          displaypath);

  if (!is_submodule_populated_gently(path, NULL))
    goto cleanup;

  strbuf_reset(&sb);
  code = get_default_remote_submodule(path, &default_remote);
  if (code)
    exit(code);

  remote_key = xstrfmt("remote.%s.url", default_remote);
  free(default_remote);

  submodule_to_gitdir(&sb, path);
  strbuf_addstr(&sb, "/config");

  if (git_config_set_in_file_gently(sb.buf, remote_key, NULL, sub_origin_url))
    die(_("failed to update remote for submodule '%s'"),
          path);

  if (flags & OPT_RECURSIVE) {
    struct child_process cpr = CHILD_PROCESS_INIT;

    cpr.git_cmd = 1;
    cpr.dir = path;
    prepare_submodule_repo_env(&cpr.env);

    strvec_pushl(&cpr.args, "submodule--helper", "sync",
           "--recursive", NULL);
    strvec_pushf(&cpr.args, "--super-prefix=%s/", displaypath);

    if (flags & OPT_QUIET)
      strvec_push(&cpr.args, "--quiet");

    if (run_command(&cpr))
      die(_("failed to recurse into submodule '%s'"),
            path);
  }

cleanup:
  free(super_config_url);
  free(sub_origin_url);
  strbuf_release(&sb);
  free(remote_key);
  free(displaypath);
  free(sub_config_path);
}

static void sync_submodule_cb(const struct cache_entry *list_item, void *cb_data)
{
  struct sync_cb *info = cb_data;

  sync_submodule(list_item->name, info->prefix, info->super_prefix,
           info->flags);
}

static int module_sync(int argc, const char **argv, const char *prefix)
{
  struct sync_cb info = SYNC_CB_INIT;
  struct pathspec pathspec = { 0 };
  struct module_list list = MODULE_LIST_INIT;
  int quiet = 0;
  int recursive = 0;
  struct option module_sync_options[] = {
    OPT__SUPER_PREFIX(&info.super_prefix),
    OPT__QUIET(&quiet, N_("suppress output of synchronizing submodule url")),
    OPT_BOOL(0, "recursive", &recursive,
      N_("recurse into nested submodules")),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule sync [--quiet] [--recursive] [<path>]"),
    NULL
  };
  int ret = 1;

  argc = parse_options(argc, argv, prefix, module_sync_options,
           git_submodule_helper_usage, 0);

  if (module_list_compute(argv, prefix, &pathspec, &list) < 0)
    goto cleanup;

  info.prefix = prefix;
  if (quiet)
    info.flags |= OPT_QUIET;
  if (recursive)
    info.flags |= OPT_RECURSIVE;

  for_each_listed_submodule(&list, sync_submodule_cb, &info);

  ret = 0;
cleanup:
  module_list_release(&list);
  clear_pathspec(&pathspec);
  return ret;
}

struct deinit_cb {
  const char *prefix;
  unsigned int flags;
};
#define DEINIT_CB_INIT { 0 }

static void deinit_submodule(const char *path, const char *prefix,
           unsigned int flags)
{
  const struct submodule *sub;
  char *displaypath = NULL;
  struct child_process cp_config = CHILD_PROCESS_INIT;
  struct strbuf sb_config = STRBUF_INIT;
  char *sub_git_dir = xstrfmt("%s/.git", path);

  if (validate_submodule_path(path) < 0)
    exit(128);

  sub = submodule_from_path(the_repository, null_oid(), path);

  if (!sub || !sub->name)
    goto cleanup;

  displaypath = get_submodule_displaypath(path, prefix, NULL);

  /* remove the submodule work tree (unless the user already did it) */
  if (is_directory(path)) {
    struct strbuf sb_rm = STRBUF_INIT;
    const char *format;

    if (is_directory(sub_git_dir)) {
      if (!(flags & OPT_QUIET))
        warning(_("Submodule work tree '%s' contains a .git "
            "directory. This will be replaced with a "
            ".git file by using absorbgitdirs."),
          displaypath);

      absorb_git_dir_into_superproject(path, NULL);

    }

    if (!(flags & OPT_FORCE)) {
      struct child_process cp_rm = CHILD_PROCESS_INIT;

      cp_rm.git_cmd = 1;
      strvec_pushl(&cp_rm.args, "rm", "-qn",
             path, NULL);

      if (run_command(&cp_rm))
        die(_("Submodule work tree '%s' contains local "
              "modifications; use '-f' to discard them"),
              displaypath);
    }

    strbuf_addstr(&sb_rm, path);

    if (!remove_dir_recursively(&sb_rm, 0))
      format = _("Cleared directory '%s'\n");
    else
      format = _("Could not remove submodule work tree '%s'\n");

    if (!(flags & OPT_QUIET))
      printf(format, displaypath);

    submodule_unset_core_worktree(sub);

    strbuf_release(&sb_rm);
  }

  if (mkdir(path, 0777))
    printf(_("could not create empty submodule directory %s"),
          displaypath);

  cp_config.git_cmd = 1;
  strvec_pushl(&cp_config.args, "config", "--get-regexp", NULL);
  strvec_pushf(&cp_config.args, "submodule.%s\\.", sub->name);

  /* remove the .git/config entries (unless the user already did it) */
  if (!capture_command(&cp_config, &sb_config, 0) && sb_config.len) {
    char *sub_key = xstrfmt("submodule.%s", sub->name);

    /*
     * remove the whole section so we have a clean state when
     * the user later decides to init this submodule again
     */
    repo_config_rename_section_in_file(the_repository, NULL, sub_key, NULL);
    if (!(flags & OPT_QUIET))
      printf(_("Submodule '%s' (%s) unregistered for path '%s'\n"),
         sub->name, sub->url, displaypath);
    free(sub_key);
  }

cleanup:
  free(displaypath);
  free(sub_git_dir);
  strbuf_release(&sb_config);
}

static void deinit_submodule_cb(const struct cache_entry *list_item,
        void *cb_data)
{
  struct deinit_cb *info = cb_data;
  deinit_submodule(list_item->name, info->prefix, info->flags);
}

static int module_deinit(int argc, const char **argv, const char *prefix)
{
  struct deinit_cb info = DEINIT_CB_INIT;
  struct pathspec pathspec = { 0 };
  struct module_list list = MODULE_LIST_INIT;
  int quiet = 0;
  int force = 0;
  int all = 0;
  struct option module_deinit_options[] = {
    OPT__QUIET(&quiet, N_("suppress submodule status output")),
    OPT__FORCE(&force, N_("remove submodule working trees even if they contain local changes"), 0),
    OPT_BOOL(0, "all", &all, N_("unregister all submodules")),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule deinit [--quiet] [-f | --force] [--all | [--] [<path>...]]"),
    NULL
  };
  int ret = 1;

  argc = parse_options(argc, argv, prefix, module_deinit_options,
           git_submodule_helper_usage, 0);

  if (all && argc) {
    error("pathspec and --all are incompatible");
    usage_with_options(git_submodule_helper_usage,
           module_deinit_options);
  }

  if (!argc && !all)
    die(_("Use '--all' if you really want to deinitialize all submodules"));

  if (module_list_compute(argv, prefix, &pathspec, &list) < 0)
    goto cleanup;

  info.prefix = prefix;
  if (quiet)
    info.flags |= OPT_QUIET;
  if (force)
    info.flags |= OPT_FORCE;

  for_each_listed_submodule(&list, deinit_submodule_cb, &info);

  ret = 0;
cleanup:
  module_list_release(&list);
  clear_pathspec(&pathspec);
  return ret;
}

struct module_clone_data {
  const char *prefix;
  const char *path;
  const char *name;
  const char *url;
  int depth;
  struct list_objects_filter_options *filter_options;
  enum ref_storage_format ref_storage_format;
  unsigned int quiet: 1;
  unsigned int progress: 1;
  unsigned int dissociate: 1;
  unsigned int require_init: 1;
  int single_branch;
};
#define MODULE_CLONE_DATA_INIT { \
  .single_branch = -1, \
  .ref_storage_format = REF_STORAGE_FORMAT_UNKNOWN, \
}

struct submodule_alternate_setup {
  const char *submodule_name;
  enum SUBMODULE_ALTERNATE_ERROR_MODE {
    SUBMODULE_ALTERNATE_ERROR_DIE,
    SUBMODULE_ALTERNATE_ERROR_INFO,
    SUBMODULE_ALTERNATE_ERROR_IGNORE
  } error_mode;
  struct string_list *reference;
};
#define SUBMODULE_ALTERNATE_SETUP_INIT { \
  .error_mode = SUBMODULE_ALTERNATE_ERROR_IGNORE, \
}

static const char alternate_error_advice[] = N_(
"An alternate computed from a superproject's alternate is invalid.\n"
"To allow Git to clone without an alternate in such a case, set\n"
"submodule.alternateErrorStrategy to 'info' or, equivalently, clone with\n"
"'--reference-if-able' instead of '--reference'."
);

static int add_possible_reference_from_superproject(
    struct object_directory *odb, void *sas_cb)
{
  struct submodule_alternate_setup *sas = sas_cb;
  size_t len;

  /*
   * If the alternate object store is another repository, try the
   * standard layout with .git/(modules/<name>)+/objects
   */
  if (strip_suffix(odb->path, "/objects", &len)) {
    struct repository alternate;
    char *sm_alternate;
    struct strbuf sb = STRBUF_INIT;
    struct strbuf err = STRBUF_INIT;
    strbuf_add(&sb, odb->path, len);

    if (repo_init(&alternate, sb.buf, NULL) < 0)
      die(_("could not get a repository handle for gitdir '%s'"),
          sb.buf);

    /*
     * We need to end the new path with '/' to mark it as a dir,
     * otherwise a submodule name containing '/' will be broken
     * as the last part of a missing submodule reference would
     * be taken as a file name.
     */
    strbuf_reset(&sb);
    submodule_name_to_gitdir(&sb, &alternate, sas->submodule_name);
    strbuf_addch(&sb, '/');
    repo_clear(&alternate);

    sm_alternate = compute_alternate_path(sb.buf, &err);
    if (sm_alternate) {
      char *p = strbuf_detach(&sb, NULL);

      string_list_append(sas->reference, p)->util = p;
      free(sm_alternate);
    } else {
      switch (sas->error_mode) {
      case SUBMODULE_ALTERNATE_ERROR_DIE:
        if (advice_enabled(ADVICE_SUBMODULE_ALTERNATE_ERROR_STRATEGY_DIE))
          advise(_(alternate_error_advice));
        die(_("submodule '%s' cannot add alternate: %s"),
            sas->submodule_name, err.buf);
      case SUBMODULE_ALTERNATE_ERROR_INFO:
        fprintf_ln(stderr, _("submodule '%s' cannot add alternate: %s"),
          sas->submodule_name, err.buf);
      case SUBMODULE_ALTERNATE_ERROR_IGNORE:
        ; /* nothing */
      }
    }
    strbuf_release(&sb);
  }

  return 0;
}

static void prepare_possible_alternates(const char *sm_name,
    struct string_list *reference)
{
  char *sm_alternate = NULL, *error_strategy = NULL;
  struct submodule_alternate_setup sas = SUBMODULE_ALTERNATE_SETUP_INIT;

  git_config_get_string("submodule.alternateLocation", &sm_alternate);
  if (!sm_alternate)
    return;

  git_config_get_string("submodule.alternateErrorStrategy", &error_strategy);

  if (!error_strategy)
    error_strategy = xstrdup("die");

  sas.submodule_name = sm_name;
  sas.reference = reference;
  if (!strcmp(error_strategy, "die"))
    sas.error_mode = SUBMODULE_ALTERNATE_ERROR_DIE;
  else if (!strcmp(error_strategy, "info"))
    sas.error_mode = SUBMODULE_ALTERNATE_ERROR_INFO;
  else if (!strcmp(error_strategy, "ignore"))
    sas.error_mode = SUBMODULE_ALTERNATE_ERROR_IGNORE;
  else
    die(_("Value '%s' for submodule.alternateErrorStrategy is not recognized"), error_strategy);

  if (!strcmp(sm_alternate, "superproject"))
    foreach_alt_odb(add_possible_reference_from_superproject, &sas);
  else if (!strcmp(sm_alternate, "no"))
    ; /* do nothing */
  else
    die(_("Value '%s' for submodule.alternateLocation is not recognized"), sm_alternate);

  free(sm_alternate);
  free(error_strategy);
}

static char *clone_submodule_sm_gitdir(const char *name)
{
  struct strbuf sb = STRBUF_INIT;
  char *sm_gitdir;

  submodule_name_to_gitdir(&sb, the_repository, name);
  sm_gitdir = absolute_pathdup(sb.buf);
  strbuf_release(&sb);

  return sm_gitdir;
}

static int dir_contains_only_dotgit(const char *path)
{
  DIR *dir = opendir(path);
  struct dirent *e;
  int ret = 1;

  if (!dir)
    return 0;

  e = readdir_skip_dot_and_dotdot(dir);
  if (!e)
    ret = 0;
  else if (strcmp(DEFAULT_GIT_DIR_ENVIRONMENT, e->d_name) ||
     (e = readdir_skip_dot_and_dotdot(dir))) {
    error("unexpected item '%s' in '%s'", e->d_name, path);
    ret = 0;
  }

  closedir(dir);
  return ret;
}

static int clone_submodule(const struct module_clone_data *clone_data,
         struct string_list *reference)
{
  char *p;
  char *sm_gitdir = clone_submodule_sm_gitdir(clone_data->name);
  char *sm_alternate = NULL, *error_strategy = NULL;
  struct stat st;
  struct child_process cp = CHILD_PROCESS_INIT;
  const char *clone_data_path = clone_data->path;
  char *to_free = NULL;

  if (validate_submodule_path(clone_data_path) < 0)
    exit(128);

  if (!is_absolute_path(clone_data->path))
    clone_data_path = to_free = xstrfmt("%s/%s", get_git_work_tree(),
                clone_data->path);

  if (validate_submodule_git_dir(sm_gitdir, clone_data->name) < 0)
    die(_("refusing to create/use '%s' in another submodule's "
          "git dir"), sm_gitdir);

  if (!file_exists(sm_gitdir)) {
    if (clone_data->require_init && !stat(clone_data_path, &st) &&
        !is_empty_dir(clone_data_path))
      die(_("directory not empty: '%s'"), clone_data_path);

    if (safe_create_leading_directories_const(sm_gitdir) < 0)
      die(_("could not create directory '%s'"), sm_gitdir);

    prepare_possible_alternates(clone_data->name, reference);

    strvec_push(&cp.args, "clone");
    strvec_push(&cp.args, "--no-checkout");
    if (clone_data->quiet)
      strvec_push(&cp.args, "--quiet");
    if (clone_data->progress)
      strvec_push(&cp.args, "--progress");
    if (clone_data->depth > 0)
      strvec_pushf(&cp.args, "--depth=%d", clone_data->depth);
    if (reference->nr) {
      struct string_list_item *item;

      for_each_string_list_item(item, reference)
        strvec_pushl(&cp.args, "--reference",
               item->string, NULL);
    }
    if (clone_data->ref_storage_format != REF_STORAGE_FORMAT_UNKNOWN)
      strvec_pushf(&cp.args, "--ref-format=%s",
             ref_storage_format_to_name(clone_data->ref_storage_format));
    if (clone_data->dissociate)
      strvec_push(&cp.args, "--dissociate");
    if (sm_gitdir && *sm_gitdir)
      strvec_pushl(&cp.args, "--separate-git-dir", sm_gitdir, NULL);
    if (clone_data->filter_options && clone_data->filter_options->choice)
      strvec_pushf(&cp.args, "--filter=%s",
             expand_list_objects_filter_spec(
               clone_data->filter_options));
    if (clone_data->single_branch >= 0)
      strvec_push(&cp.args, clone_data->single_branch ?
            "--single-branch" :
            "--no-single-branch");

    strvec_push(&cp.args, "--");
    strvec_push(&cp.args, clone_data->url);
    strvec_push(&cp.args, clone_data_path);

    cp.git_cmd = 1;
    prepare_submodule_repo_env(&cp.env);
    cp.no_stdin = 1;

    if(run_command(&cp))
      die(_("clone of '%s' into submodule path '%s' failed"),
          clone_data->url, clone_data_path);

    if (clone_data->require_init && !stat(clone_data_path, &st) &&
        !dir_contains_only_dotgit(clone_data_path)) {
      char *dot_git = xstrfmt("%s/.git", clone_data_path);
      unlink(dot_git);
      free(dot_git);
      die(_("directory not empty: '%s'"), clone_data_path);
    }
  } else {
    char *path;

    if (clone_data->require_init && !stat(clone_data_path, &st) &&
        !is_empty_dir(clone_data_path))
      die(_("directory not empty: '%s'"), clone_data_path);
    if (safe_create_leading_directories_const(clone_data_path) < 0)
      die(_("could not create directory '%s'"), clone_data_path);
    path = xstrfmt("%s/index", sm_gitdir);
    unlink_or_warn(path);
    free(path);
  }

  /*
   * We already performed this check at the beginning of this function,
   * before cloning the objects. This tries to detect racy behavior e.g.
   * in parallel clones, where another process could easily have made the
   * gitdir nested _after_ it was created.
   *
   * To prevent further harm coming from this unintentionally-nested
   * gitdir, let's disable it by deleting the `HEAD` file.
   */
  if (validate_submodule_git_dir(sm_gitdir, clone_data->name) < 0) {
    char *head = xstrfmt("%s/HEAD", sm_gitdir);
    unlink(head);
    free(head);
    die(_("refusing to create/use '%s' in another submodule's "
          "git dir"), sm_gitdir);
  }

  connect_work_tree_and_git_dir(clone_data_path, sm_gitdir, 0);

  p = git_pathdup_submodule(clone_data_path, "config");
  if (!p)
    die(_("could not get submodule directory for '%s'"), clone_data_path);

  /* setup alternateLocation and alternateErrorStrategy in the cloned submodule if needed */
  git_config_get_string("submodule.alternateLocation", &sm_alternate);
  if (sm_alternate)
    git_config_set_in_file(p, "submodule.alternateLocation",
               sm_alternate);
  git_config_get_string("submodule.alternateErrorStrategy", &error_strategy);
  if (error_strategy)
    git_config_set_in_file(p, "submodule.alternateErrorStrategy",
               error_strategy);

  free(sm_alternate);
  free(error_strategy);

  free(sm_gitdir);
  free(p);
  free(to_free);
  return 0;
}

static int module_clone(int argc, const char **argv, const char *prefix)
{
  int dissociate = 0, quiet = 0, progress = 0, require_init = 0;
  struct module_clone_data clone_data = MODULE_CLONE_DATA_INIT;
  struct string_list reference = STRING_LIST_INIT_NODUP;
  struct list_objects_filter_options filter_options =
    LIST_OBJECTS_FILTER_INIT;
  const char *ref_storage_format = NULL;

  struct option module_clone_options[] = {
    OPT_STRING(0, "prefix", &clone_data.prefix,
         N_("path"),
         N_("alternative anchor for relative paths")),
    OPT_STRING(0, "path", &clone_data.path,
         N_("path"),
         N_("where the new submodule will be cloned to")),
    OPT_STRING(0, "name", &clone_data.name,
         N_("string"),
         N_("name of the new submodule")),
    OPT_STRING(0, "url", &clone_data.url,
         N_("string"),
         N_("url where to clone the submodule from")),
    OPT_STRING_LIST(0, "reference", &reference,
         N_("repo"),
         N_("reference repository")),
    OPT_STRING(0, "ref-format", &ref_storage_format, N_("format"),
         N_("specify the reference format to use")),
    OPT_BOOL(0, "dissociate", &dissociate,
         N_("use --reference only while cloning")),
    OPT_INTEGER(0, "depth", &clone_data.depth,
         N_("depth for shallow clones")),
    OPT__QUIET(&quiet, "suppress output for cloning a submodule"),
    OPT_BOOL(0, "progress", &progress,
         N_("force cloning progress")),
    OPT_BOOL(0, "require-init", &require_init,
         N_("disallow cloning into non-empty directory")),
    OPT_BOOL(0, "single-branch", &clone_data.single_branch,
       N_("clone only one branch, HEAD or --branch")),
    OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule--helper clone [--prefix=<path>] [--quiet] "
       "[--reference <repository>] [--name <name>] [--depth <depth>] "
       "[--single-branch] [--filter <filter-spec>] "
       "--url <url> --path <path>"),
    NULL
  };

  argc = parse_options(argc, argv, prefix, module_clone_options,
           git_submodule_helper_usage, 0);

  if (ref_storage_format) {
    clone_data.ref_storage_format = ref_storage_format_by_name(ref_storage_format);
    if (clone_data.ref_storage_format == REF_STORAGE_FORMAT_UNKNOWN)
      die(_("unknown ref storage format '%s'"), ref_storage_format);
  }
  clone_data.dissociate = !!dissociate;
  clone_data.quiet = !!quiet;
  clone_data.progress = !!progress;
  clone_data.require_init = !!require_init;
  clone_data.filter_options = &filter_options;

  if (argc || !clone_data.url || !clone_data.path || !*(clone_data.path))
    usage_with_options(git_submodule_helper_usage,
           module_clone_options);

  clone_submodule(&clone_data, &reference);
  list_objects_filter_release(&filter_options);
  string_list_clear(&reference, 1);
  return 0;
}

static int determine_submodule_update_strategy(struct repository *r,
                 int just_cloned,
                 const char *path,
                 enum submodule_update_type update,
                 struct submodule_update_strategy *out)
{
  const struct submodule *sub = submodule_from_path(r, null_oid(), path);
  char *key;
  const char *val;
  int ret;

  key = xstrfmt("submodule.%s.update", sub->name);

  if (update) {
    out->type = update;
  } else if (!repo_config_get_string_tmp(r, key, &val)) {
    if (parse_submodule_update_strategy(val, out) < 0) {
      ret = die_message(_("Invalid update mode '%s' configured for submodule path '%s'"),
            val, path);
      goto cleanup;
    }
  } else if (sub->update_strategy.type != SM_UPDATE_UNSPECIFIED) {
    if (sub->update_strategy.type == SM_UPDATE_COMMAND)
      BUG("how did we read update = !command from .gitmodules?");
    out->type = sub->update_strategy.type;
    out->command = sub->update_strategy.command;
  } else
    out->type = SM_UPDATE_CHECKOUT;

  if (just_cloned &&
      (out->type == SM_UPDATE_MERGE ||
       out->type == SM_UPDATE_REBASE ||
       out->type == SM_UPDATE_NONE))
    out->type = SM_UPDATE_CHECKOUT;

  ret = 0;
cleanup:
  free(key);
  return ret;
}

struct update_clone_data {
  const struct submodule *sub;
  struct object_id oid;
  unsigned just_cloned;
};

struct submodule_update_clone {
  /* index into 'update_data.list', the list of submodules to look into for cloning */
  int current;

  /* configuration parameters which are passed on to the children */
  const struct update_data *update_data;

  /* to be consumed by update_submodule() */
  struct update_clone_data *update_clone;
  int update_clone_nr; int update_clone_alloc;

  /* If we want to stop as fast as possible and return an error */
  unsigned quickstop : 1;

  /* failed clones to be retried again */
  const struct cache_entry **failed_clones;
  int failed_clones_nr, failed_clones_alloc;
};
#define SUBMODULE_UPDATE_CLONE_INIT { 0 }

static void submodule_update_clone_release(struct submodule_update_clone *suc)
{
  free(suc->update_clone);
  free(suc->failed_clones);
}

struct update_data {
  const char *prefix;
  const char *super_prefix;
  char *displaypath;
  enum submodule_update_type update_default;
  struct object_id suboid;
  struct string_list references;
  struct submodule_update_strategy update_strategy;
  struct list_objects_filter_options *filter_options;
  struct module_list list;
  enum ref_storage_format ref_storage_format;
  int depth;
  int max_jobs;
  int single_branch;
  int recommend_shallow;
  unsigned int require_init;
  unsigned int force;
  unsigned int quiet;
  unsigned int nofetch;
  unsigned int remote;
  unsigned int progress;
  unsigned int dissociate;
  unsigned int init;
  unsigned int warn_if_uninitialized;
  unsigned int recursive;

  /* copied over from update_clone_data */
  struct object_id oid;
  unsigned int just_cloned;
  const char *sm_path;
};
#define UPDATE_DATA_INIT { \
  .update_strategy = SUBMODULE_UPDATE_STRATEGY_INIT, \
  .list = MODULE_LIST_INIT, \
  .ref_storage_format = REF_STORAGE_FORMAT_UNKNOWN, \
  .recommend_shallow = -1, \
  .references = STRING_LIST_INIT_DUP, \
  .single_branch = -1, \
  .max_jobs = 1, \
}

static void update_data_release(struct update_data *ud)
{
  free(ud->displaypath);
  module_list_release(&ud->list);
}

static void next_submodule_warn_missing(struct submodule_update_clone *suc,
    struct strbuf *out, const char *displaypath)
{
  /*
   * Only mention uninitialized submodules when their
   * paths have been specified.
   */
  if (suc->update_data->warn_if_uninitialized) {
    strbuf_addf(out,
      _("Submodule path '%s' not initialized"),
      displaypath);
    strbuf_addch(out, '\n');
    strbuf_addstr(out,
      _("Maybe you want to use 'update --init'?"));
    strbuf_addch(out, '\n');
  }
}

/**
 * Determine whether 'ce' needs to be cloned. If so, prepare the 'child' to
 * run the clone. Returns 1 if 'ce' needs to be cloned, 0 otherwise.
 */
static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
             struct child_process *child,
             struct submodule_update_clone *suc,
             struct strbuf *out)
{
  const struct submodule *sub = NULL;
  const char *url = NULL;
  const char *update_string;
  enum submodule_update_type update_type;
  char *key;
  const struct update_data *ud = suc->update_data;
  char *displaypath = get_submodule_displaypath(ce->name, ud->prefix,
                  ud->super_prefix);
  struct strbuf sb = STRBUF_INIT;
  int needs_cloning = 0;
  int need_free_url = 0;

  if (ce_stage(ce)) {
    strbuf_addf(out, _("Skipping unmerged submodule %s"), displaypath);
    strbuf_addch(out, '\n');
    goto cleanup;
  }

  sub = submodule_from_path(the_repository, null_oid(), ce->name);

  if (!sub) {
    next_submodule_warn_missing(suc, out, displaypath);
    goto cleanup;
  }

  key = xstrfmt("submodule.%s.update", sub->name);
  if (!repo_config_get_string_tmp(the_repository, key, &update_string)) {
    update_type = parse_submodule_update_type(update_string);
  } else {
    update_type = sub->update_strategy.type;
  }
  free(key);

  if (suc->update_data->update_strategy.type == SM_UPDATE_NONE
      || (suc->update_data->update_strategy.type == SM_UPDATE_UNSPECIFIED
    && update_type == SM_UPDATE_NONE)) {
    strbuf_addf(out, _("Skipping submodule '%s'"), displaypath);
    strbuf_addch(out, '\n');
    goto cleanup;
  }

  /* Check if the submodule has been initialized. */
  if (!is_submodule_active(the_repository, ce->name)) {
    next_submodule_warn_missing(suc, out, displaypath);
    goto cleanup;
  }

  strbuf_reset(&sb);
  strbuf_addf(&sb, "submodule.%s.url", sub->name);
  if (repo_config_get_string_tmp(the_repository, sb.buf, &url)) {
    if (sub->url && (starts_with_dot_slash(sub->url) ||
         starts_with_dot_dot_slash(sub->url))) {
      url = resolve_relative_url(sub->url, NULL, 0);
      need_free_url = 1;
    } else
      url = sub->url;
  }

  if (!url)
    die(_("cannot clone submodule '%s' without a URL"), sub->name);

  strbuf_reset(&sb);
  strbuf_addf(&sb, "%s/.git", ce->name);
  needs_cloning = !file_exists(sb.buf);

  ALLOC_GROW(suc->update_clone, suc->update_clone_nr + 1,
       suc->update_clone_alloc);
  oidcpy(&suc->update_clone[suc->update_clone_nr].oid, &ce->oid);
  suc->update_clone[suc->update_clone_nr].just_cloned = needs_cloning;
  suc->update_clone[suc->update_clone_nr].sub = sub;
  suc->update_clone_nr++;

  if (!needs_cloning)
    goto cleanup;

  child->git_cmd = 1;
  child->no_stdin = 1;
  child->stdout_to_stderr = 1;
  child->err = -1;
  strvec_push(&child->args, "submodule--helper");
  strvec_push(&child->args, "clone");
  if (suc->update_data->progress)
    strvec_push(&child->args, "--progress");
  if (suc->update_data->quiet)
    strvec_push(&child->args, "--quiet");
  if (suc->update_data->prefix)
    strvec_pushl(&child->args, "--prefix", suc->update_data->prefix, NULL);
  if (suc->update_data->recommend_shallow && sub->recommend_shallow == 1)
    strvec_push(&child->args, "--depth=1");
  else if (suc->update_data->depth)
    strvec_pushf(&child->args, "--depth=%d", suc->update_data->depth);
  if (suc->update_data->filter_options && suc->update_data->filter_options->choice)
    strvec_pushf(&child->args, "--filter=%s",
           expand_list_objects_filter_spec(suc->update_data->filter_options));
  if (suc->update_data->require_init)
    strvec_push(&child->args, "--require-init");
  if (suc->update_data->ref_storage_format != REF_STORAGE_FORMAT_UNKNOWN)
    strvec_pushf(&child->args, "--ref-format=%s",
           ref_storage_format_to_name(suc->update_data->ref_storage_format));
  strvec_pushl(&child->args, "--path", sub->path, NULL);
  strvec_pushl(&child->args, "--name", sub->name, NULL);
  strvec_pushl(&child->args, "--url", url, NULL);
  if (suc->update_data->references.nr) {
    struct string_list_item *item;

    for_each_string_list_item(item, &suc->update_data->references)
      strvec_pushl(&child->args, "--reference", item->string, NULL);
  }
  if (suc->update_data->dissociate)
    strvec_push(&child->args, "--dissociate");
  if (suc->update_data->single_branch >= 0)
    strvec_push(&child->args, suc->update_data->single_branch ?
                "--single-branch" :
                "--no-single-branch");

cleanup:
  free(displaypath);
  strbuf_release(&sb);
  if (need_free_url)
    free((void*)url);

  return needs_cloning;
}

static int update_clone_get_next_task(struct child_process *child,
              struct strbuf *err,
              void *suc_cb,
              void **idx_task_cb)
{
  struct submodule_update_clone *suc = suc_cb;
  const struct cache_entry *ce;
  int index;

  for (; suc->current < suc->update_data->list.nr; suc->current++) {
    ce = suc->update_data->list.entries[suc->current];
    if (prepare_to_clone_next_submodule(ce, child, suc, err)) {
      int *p = xmalloc(sizeof(*p));

      *p = suc->current;
      *idx_task_cb = p;
      suc->current++;
      return 1;
    }
  }

  /*
   * The loop above tried cloning each submodule once, now try the
   * stragglers again, which we can imagine as an extension of the
   * entry list.
   */
  index = suc->current - suc->update_data->list.nr;
  if (index < suc->failed_clones_nr) {
    int *p;

    ce = suc->failed_clones[index];
    if (!prepare_to_clone_next_submodule(ce, child, suc, err)) {
      suc->current ++;
      strbuf_addstr(err, "BUG: submodule considered for "
             "cloning, doesn't need cloning "
             "any more?\n");
      return 0;
    }
    p = xmalloc(sizeof(*p));
    *p = suc->current;
    *idx_task_cb = p;
    suc->current ++;
    return 1;
  }

  return 0;
}

static int update_clone_start_failure(struct strbuf *err UNUSED,
              void *suc_cb,
              void *idx_task_cb UNUSED)
{
  struct submodule_update_clone *suc = suc_cb;

  suc->quickstop = 1;
  return 1;
}

static int update_clone_task_finished(int result,
              struct strbuf *err,
              void *suc_cb,
              void *idx_task_cb)
{
  const struct cache_entry *ce;
  struct submodule_update_clone *suc = suc_cb;
  int *idxP = idx_task_cb;
  int idx = *idxP;

  free(idxP);

  if (!result)
    return 0;

  if (idx < suc->update_data->list.nr) {
    ce  = suc->update_data->list.entries[idx];
    strbuf_addf(err, _("Failed to clone '%s'. Retry scheduled"),
          ce->name);
    strbuf_addch(err, '\n');
    ALLOC_GROW(suc->failed_clones,
         suc->failed_clones_nr + 1,
         suc->failed_clones_alloc);
    suc->failed_clones[suc->failed_clones_nr++] = ce;
    return 0;
  } else {
    idx -= suc->update_data->list.nr;
    ce  = suc->failed_clones[idx];
    strbuf_addf(err, _("Failed to clone '%s' a second time, aborting"),
          ce->name);
    strbuf_addch(err, '\n');
    suc->quickstop = 1;
    return 1;
  }

  return 0;
}

static int git_update_clone_config(const char *var, const char *value,
           const struct config_context *ctx,
           void *cb)
{
  int *max_jobs = cb;

  if (!strcmp(var, "submodule.fetchjobs"))
    *max_jobs = parse_submodule_fetchjobs(var, value, ctx->kvi);
  return 0;
}

static int is_tip_reachable(const char *path, const struct object_id *oid)
{
  struct child_process cp = CHILD_PROCESS_INIT;
  struct strbuf rev = STRBUF_INIT;
  char *hex = oid_to_hex(oid);
  int reachable;

  cp.git_cmd = 1;
  cp.dir = path;
  cp.no_stderr = 1;
  strvec_pushl(&cp.args, "rev-list", "-n", "1", hex, "--not", "--all", NULL);

  prepare_submodule_repo_env(&cp.env);

  if (capture_command(&cp, &rev, GIT_MAX_HEXSZ + 1) || rev.len)
    reachable = 0;
  else
    reachable = 1;

  strbuf_release(&rev);
  return reachable;
}

static int fetch_in_submodule(const char *module_path, int depth, int quiet,
            const struct object_id *oid)
{
  struct child_process cp = CHILD_PROCESS_INIT;

  prepare_submodule_repo_env(&cp.env);
  cp.git_cmd = 1;
  cp.dir = module_path;

  strvec_push(&cp.args, "fetch");
  if (quiet)
    strvec_push(&cp.args, "--quiet");
  if (depth)
    strvec_pushf(&cp.args, "--depth=%d", depth);
  if (oid) {
    char *hex = oid_to_hex(oid);
    char *remote = get_default_remote();

    strvec_pushl(&cp.args, remote, hex, NULL);
    free(remote);
  }

  return run_command(&cp);
}

static int run_update_command(const struct update_data *ud, int subforce)
{
  struct child_process cp = CHILD_PROCESS_INIT;
  char *oid = oid_to_hex(&ud->oid);
  int ret;

  switch (ud->update_strategy.type) {
  case SM_UPDATE_CHECKOUT:
    cp.git_cmd = 1;
    strvec_pushl(&cp.args, "checkout", "-q", NULL);
    if (subforce)
      strvec_push(&cp.args, "-f");
    break;
  case SM_UPDATE_REBASE:
    cp.git_cmd = 1;
    strvec_push(&cp.args, "rebase");
    if (ud->quiet)
      strvec_push(&cp.args, "--quiet");
    break;
  case SM_UPDATE_MERGE:
    cp.git_cmd = 1;
    strvec_push(&cp.args, "merge");
    if (ud->quiet)
      strvec_push(&cp.args, "--quiet");
    break;
  case SM_UPDATE_COMMAND:
    cp.use_shell = 1;
    strvec_push(&cp.args, ud->update_strategy.command);
    break;
  default:
    BUG("unexpected update strategy type: %d",
        ud->update_strategy.type);
  }
  strvec_push(&cp.args, oid);

  cp.dir = ud->sm_path;
  prepare_submodule_repo_env(&cp.env);
  if ((ret = run_command(&cp))) {
    switch (ud->update_strategy.type) {
    case SM_UPDATE_CHECKOUT:
      die_message(_("Unable to checkout '%s' in submodule path '%s'"),
            oid, ud->displaypath);
      /* No "ret" assignment, use "git checkout"'s */
      break;
    case SM_UPDATE_REBASE:
      ret = die_message(_("Unable to rebase '%s' in submodule path '%s'"),
            oid, ud->displaypath);
      break;
    case SM_UPDATE_MERGE:
      ret = die_message(_("Unable to merge '%s' in submodule path '%s'"),
            oid, ud->displaypath);
      break;
    case SM_UPDATE_COMMAND:
      ret = die_message(_("Execution of '%s %s' failed in submodule path '%s'"),
            ud->update_strategy.command, oid, ud->displaypath);
      break;
    default:
      BUG("unexpected update strategy type: %d",
          ud->update_strategy.type);
    }

    return ret;
  }

  if (ud->quiet)
    return 0;

  switch (ud->update_strategy.type) {
  case SM_UPDATE_CHECKOUT:
    printf(_("Submodule path '%s': checked out '%s'\n"),
           ud->displaypath, oid);
    break;
  case SM_UPDATE_REBASE:
    printf(_("Submodule path '%s': rebased into '%s'\n"),
           ud->displaypath, oid);
    break;
  case SM_UPDATE_MERGE:
    printf(_("Submodule path '%s': merged in '%s'\n"),
           ud->displaypath, oid);
    break;
  case SM_UPDATE_COMMAND:
    printf(_("Submodule path '%s': '%s %s'\n"),
           ud->displaypath, ud->update_strategy.command, oid);
    break;
  default:
    BUG("unexpected update strategy type: %d",
        ud->update_strategy.type);
  }

  return 0;
}

static int run_update_procedure(const struct update_data *ud)
{
  int subforce = is_null_oid(&ud->suboid) || ud->force;

  if (!ud->nofetch) {
    /*
     * Run fetch only if `oid` isn't present or it
     * is not reachable from a ref.
     */
    if (!is_tip_reachable(ud->sm_path, &ud->oid) &&
        fetch_in_submodule(ud->sm_path, ud->depth, ud->quiet, NULL) &&
        !ud->quiet)
      fprintf_ln(stderr,
           _("Unable to fetch in submodule path '%s'; "
             "trying to directly fetch %s:"),
           ud->displaypath, oid_to_hex(&ud->oid));
    /*
     * Now we tried the usual fetch, but `oid` may
     * not be reachable from any of the refs.
     */
    if (!is_tip_reachable(ud->sm_path, &ud->oid) &&
        fetch_in_submodule(ud->sm_path, ud->depth, ud->quiet, &ud->oid))
      return die_message(_("Fetched in submodule path '%s', but it did not "
               "contain %s. Direct fetching of that commit failed."),
             ud->displaypath, oid_to_hex(&ud->oid));
  }

  return run_update_command(ud, subforce);
}

static int remote_submodule_branch(const char *path, const char **branch)
{
  const struct submodule *sub;
  char *key;
  *branch = NULL;

  sub = submodule_from_path(the_repository, null_oid(), path);
  if (!sub)
    return die_message(_("could not initialize submodule at path '%s'"),
           path);

  key = xstrfmt("submodule.%s.branch", sub->name);
  if (repo_config_get_string_tmp(the_repository, key, branch))
    *branch = sub->branch;
  free(key);

  if (!*branch) {
    *branch = "HEAD";
    return 0;
  }

  if (!strcmp(*branch, ".")) {
    const char *refname = refs_resolve_ref_unsafe(get_main_ref_store(the_repository),
                    "HEAD", 0, NULL,
                    NULL);

    if (!refname)
      return die_message(_("No such ref: %s"), "HEAD");

    /* detached HEAD */
    if (!strcmp(refname, "HEAD"))
      return die_message(_("Submodule (%s) branch configured to inherit "
               "branch from superproject, but the superproject "
               "is not on any branch"), sub->name);

    if (!skip_prefix(refname, "refs/heads/", &refname))
      return die_message(_("Expecting a full ref name, got %s"),
             refname);

    *branch = refname;
    return 0;
  }

  /* Our "branch" is coming from repo_config_get_string_tmp() */
  return 0;
}

static int ensure_core_worktree(const char *path)
{
  const char *cw;
  struct repository subrepo;

  if (repo_submodule_init(&subrepo, the_repository, path, null_oid()))
    return die_message(_("could not get a repository handle for submodule '%s'"),
           path);

  if (!repo_config_get_string_tmp(&subrepo, "core.worktree", &cw)) {
    char *cfg_file, *abs_path;
    const char *rel_path;
    struct strbuf sb = STRBUF_INIT;

    cfg_file = repo_git_path(&subrepo, "config");

    abs_path = absolute_pathdup(path);
    rel_path = relative_path(abs_path, subrepo.gitdir, &sb);

    git_config_set_in_file(cfg_file, "core.worktree", rel_path);

    free(cfg_file);
    free(abs_path);
    strbuf_release(&sb);
  }

  repo_clear(&subrepo);
  return 0;
}

static const char *submodule_update_type_to_label(enum submodule_update_type type)
{
  switch (type) {
  case SM_UPDATE_CHECKOUT:
    return "checkout";
  case SM_UPDATE_MERGE:
    return "merge";
  case SM_UPDATE_REBASE:
    return "rebase";
  case SM_UPDATE_UNSPECIFIED:
  case SM_UPDATE_NONE:
  case SM_UPDATE_COMMAND:
    break;
  }
  BUG("unreachable with type %d", type);
}

static void update_data_to_args(const struct update_data *update_data,
        struct strvec *args)
{
  enum submodule_update_type update_type = update_data->update_default;

  strvec_pushl(args, "submodule--helper", "update", "--recursive", NULL);
  if (update_data->displaypath)
    strvec_pushf(args, "--super-prefix=%s/",
           update_data->displaypath);
  strvec_pushf(args, "--jobs=%d", update_data->max_jobs);
  if (update_data->quiet)
    strvec_push(args, "--quiet");
  if (update_data->force)
    strvec_push(args, "--force");
  if (update_data->init)
    strvec_push(args, "--init");
  if (update_data->remote)
    strvec_push(args, "--remote");
  if (update_data->nofetch)
    strvec_push(args, "--no-fetch");
  if (update_data->dissociate)
    strvec_push(args, "--dissociate");
  if (update_data->progress)
    strvec_push(args, "--progress");
  if (update_data->require_init)
    strvec_push(args, "--require-init");
  if (update_data->depth)
    strvec_pushf(args, "--depth=%d", update_data->depth);
  if (update_type != SM_UPDATE_UNSPECIFIED)
    strvec_pushf(args, "--%s",
           submodule_update_type_to_label(update_type));

  if (update_data->references.nr) {
    struct string_list_item *item;

    for_each_string_list_item(item, &update_data->references)
      strvec_pushl(args, "--reference", item->string, NULL);
  }
  if (update_data->ref_storage_format != REF_STORAGE_FORMAT_UNKNOWN)
    strvec_pushf(args, "--ref-format=%s",
           ref_storage_format_to_name(update_data->ref_storage_format));
  if (update_data->filter_options && update_data->filter_options->choice)
    strvec_pushf(args, "--filter=%s",
        expand_list_objects_filter_spec(
          update_data->filter_options));
  if (update_data->recommend_shallow == 0)
    strvec_push(args, "--no-recommend-shallow");
  else if (update_data->recommend_shallow == 1)
    strvec_push(args, "--recommend-shallow");
  if (update_data->single_branch >= 0)
    strvec_push(args, update_data->single_branch ?
            "--single-branch" :
            "--no-single-branch");
}

static int update_submodule(struct update_data *update_data)
{
  int ret;

  if (validate_submodule_path(update_data->sm_path) < 0)
    return -1;

  ret = determine_submodule_update_strategy(the_repository,
              update_data->just_cloned,
              update_data->sm_path,
              update_data->update_default,
              &update_data->update_strategy);
  if (ret)
    return ret;

  if (update_data->just_cloned)
    oidcpy(&update_data->suboid, null_oid());
  else if (repo_resolve_gitlink_ref(the_repository, update_data->sm_path,
            "HEAD", &update_data->suboid))
    return die_message(_("Unable to find current revision in submodule path '%s'"),
           update_data->displaypath);

  if (update_data->remote) {
    char *remote_name;
    const char *branch;
    char *remote_ref;
    int code;

    code = get_default_remote_submodule(update_data->sm_path, &remote_name);
    if (code)
      return code;
    code = remote_submodule_branch(update_data->sm_path, &branch);
    if (code)
      return code;
    remote_ref = xstrfmt("refs/remotes/%s/%s", remote_name, branch);

    free(remote_name);

    if (!update_data->nofetch) {
      if (fetch_in_submodule(update_data->sm_path, update_data->depth,
                0, NULL))
        return die_message(_("Unable to fetch in submodule path '%s'"),
               update_data->sm_path);
    }

    if (repo_resolve_gitlink_ref(the_repository, update_data->sm_path,
               remote_ref, &update_data->oid))
      return die_message(_("Unable to find %s revision in submodule path '%s'"),
             remote_ref, update_data->sm_path);

    free(remote_ref);
  }

  if (!oideq(&update_data->oid, &update_data->suboid) || update_data->force) {
    ret = run_update_procedure(update_data);
    if (ret)
      return ret;
  }

  if (update_data->recursive) {
    struct child_process cp = CHILD_PROCESS_INIT;
    struct update_data next = *update_data;

    next.prefix = NULL;
    oidcpy(&next.oid, null_oid());
    oidcpy(&next.suboid, null_oid());

    cp.dir = update_data->sm_path;
    cp.git_cmd = 1;
    prepare_submodule_repo_env(&cp.env);
    update_data_to_args(&next, &cp.args);

    ret = run_command(&cp);
    if (ret)
      die_message(_("Failed to recurse into submodule path '%s'"),
            update_data->displaypath);
    return ret;
  }

  return 0;
}

static int update_submodules(struct update_data *update_data)
{
  int i, ret = 0;
  struct submodule_update_clone suc = SUBMODULE_UPDATE_CLONE_INIT;
  const struct run_process_parallel_opts opts = {
    .tr2_category = "submodule",
    .tr2_label = "parallel/update",

    .processes = update_data->max_jobs,

    .get_next_task = update_clone_get_next_task,
    .start_failure = update_clone_start_failure,
    .task_finished = update_clone_task_finished,
    .data = &suc,
  };

  suc.update_data = update_data;
  run_processes_parallel(&opts);

  /*
   * We saved the output and put it out all at once now.
   * That means:
   * - the listener does not have to interleave their (checkout)
   *   work with our fetching.  The writes involved in a
   *   checkout involve more straightforward sequential I/O.
   * - the listener can avoid doing any work if fetching failed.
   */
  if (suc.quickstop) {
    ret = 1;
    goto cleanup;
  }

  for (i = 0; i < suc.update_clone_nr; i++) {
    struct update_clone_data ucd = suc.update_clone[i];
    int code = 128;

    oidcpy(&update_data->oid, &ucd.oid);
    update_data->just_cloned = ucd.just_cloned;
    update_data->sm_path = ucd.sub->path;

    /*
     * Verify that the submodule path does not contain any
     * symlinks; if it does, it might have been tampered with.
     * TODO: allow exempting it via
     * `safe.submodule.path` or something
     */
    if (validate_submodule_path(update_data->sm_path) < 0)
      goto fail;

    code = ensure_core_worktree(update_data->sm_path);
    if (code)
      goto fail;

    update_data->displaypath = get_submodule_displaypath(
      update_data->sm_path, update_data->prefix,
      update_data->super_prefix);
    code = update_submodule(update_data);
    FREE_AND_NULL(update_data->displaypath);
fail:
    if (!code)
      continue;
    ret = code;
    if (ret == 128)
      goto cleanup;
  }

cleanup:
  submodule_update_clone_release(&suc);
  string_list_clear(&update_data->references, 0);
  return ret;
}

static int module_update(int argc, const char **argv, const char *prefix)
{
  struct pathspec pathspec = { 0 };
  struct pathspec pathspec2 = { 0 };
  struct update_data opt = UPDATE_DATA_INIT;
  struct list_objects_filter_options filter_options =
    LIST_OBJECTS_FILTER_INIT;
  const char *ref_storage_format = NULL;
  int ret;
  struct option module_update_options[] = {
    OPT__SUPER_PREFIX(&opt.super_prefix),
    OPT__FORCE(&opt.force, N_("force checkout updates"), 0),
    OPT_BOOL(0, "init", &opt.init,
       N_("initialize uninitialized submodules before update")),
    OPT_BOOL(0, "remote", &opt.remote,
       N_("use SHA-1 of submodule's remote tracking branch")),
    OPT_BOOL(0, "recursive", &opt.recursive,
       N_("traverse submodules recursively")),
    OPT_BOOL('N', "no-fetch", &opt.nofetch,
       N_("don't fetch new objects from the remote site")),
    OPT_SET_INT(0, "checkout", &opt.update_default,
      N_("use the 'checkout' update strategy (default)"),
      SM_UPDATE_CHECKOUT),
    OPT_SET_INT('m', "merge", &opt.update_default,
      N_("use the 'merge' update strategy"),
      SM_UPDATE_MERGE),
    OPT_SET_INT('r', "rebase", &opt.update_default,
      N_("use the 'rebase' update strategy"),
      SM_UPDATE_REBASE),
    OPT_STRING_LIST(0, "reference", &opt.references, N_("repo"),
         N_("reference repository")),
    OPT_STRING(0, "ref-format", &ref_storage_format, N_("format"),
         N_("specify the reference format to use")),
    OPT_BOOL(0, "dissociate", &opt.dissociate,
         N_("use --reference only while cloning")),
    OPT_INTEGER(0, "depth", &opt.depth,
         N_("create a shallow clone truncated to the "
            "specified number of revisions")),
    OPT_INTEGER('j', "jobs", &opt.max_jobs,
          N_("parallel jobs")),
    OPT_BOOL(0, "recommend-shallow", &opt.recommend_shallow,
          N_("whether the initial clone should follow the shallow recommendation")),
    OPT__QUIET(&opt.quiet, N_("don't print cloning progress")),
    OPT_BOOL(0, "progress", &opt.progress,
          N_("force cloning progress")),
    OPT_BOOL(0, "require-init", &opt.require_init,
         N_("disallow cloning into non-empty directory, implies --init")),
    OPT_BOOL(0, "single-branch", &opt.single_branch,
       N_("clone only one branch, HEAD or --branch")),
    OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule [--quiet] update"
    " [--init [--filter=<filter-spec>]] [--remote]"
    " [-N|--no-fetch] [-f|--force]"
    " [--checkout|--merge|--rebase]"
    " [--[no-]recommend-shallow] [--reference <repository>]"
    " [--recursive] [--[no-]single-branch] [--] [<path>...]"),
    NULL
  };

  update_clone_config_from_gitmodules(&opt.max_jobs);
  git_config(git_update_clone_config, &opt.max_jobs);

  argc = parse_options(argc, argv, prefix, module_update_options,
           git_submodule_helper_usage, 0);

  if (opt.require_init)
    opt.init = 1;

  if (filter_options.choice && !opt.init) {
    usage_with_options(git_submodule_helper_usage,
           module_update_options);
  }

  if (ref_storage_format) {
    opt.ref_storage_format = ref_storage_format_by_name(ref_storage_format);
    if (opt.ref_storage_format == REF_STORAGE_FORMAT_UNKNOWN)
      die(_("unknown ref storage format '%s'"), ref_storage_format);
  }

  opt.filter_options = &filter_options;
  opt.prefix = prefix;

  if (opt.update_default)
    opt.update_strategy.type = opt.update_default;

  if (module_list_compute(argv, prefix, &pathspec, &opt.list) < 0) {
    ret = 1;
    goto cleanup;
  }

  if (pathspec.nr)
    opt.warn_if_uninitialized = 1;

  if (opt.init) {
    struct module_list list = MODULE_LIST_INIT;
    struct init_cb info = INIT_CB_INIT;

    if (module_list_compute(argv, opt.prefix,
          &pathspec2, &list) < 0) {
      module_list_release(&list);
      ret = 1;
      goto cleanup;
    }

    /*
     * If there are no path args and submodule.active is set then,
     * by default, only initialize 'active' modules.
     */
    if (!argc && !git_config_get("submodule.active"))
      module_list_active(&list);

    info.prefix = opt.prefix;
    info.super_prefix = opt.super_prefix;
    if (opt.quiet)
      info.flags |= OPT_QUIET;

    for_each_listed_submodule(&list, init_submodule_cb, &info);
    module_list_release(&list);
  }

  ret = update_submodules(&opt);
cleanup:
  update_data_release(&opt);
  list_objects_filter_release(&filter_options);
  clear_pathspec(&pathspec);
  clear_pathspec(&pathspec2);
  return ret;
}

static int push_check(int argc, const char **argv, const char *prefix UNUSED)
{
  struct remote *remote;
  const char *superproject_head;
  char *head;
  int detached_head = 0;
  struct object_id head_oid;

  if (argc < 3)
    die("submodule--helper push-check requires at least 2 arguments");

  /*
   * superproject's resolved head ref.
   * if HEAD then the superproject is in a detached head state, otherwise
   * it will be the resolved head ref.
   */
  superproject_head = argv[1];
  argv++;
  argc--;
  /* Get the submodule's head ref and determine if it is detached */
  head = refs_resolve_refdup(get_main_ref_store(the_repository), "HEAD",
           0, &head_oid, NULL);
  if (!head)
    die(_("Failed to resolve HEAD as a valid ref."));
  if (!strcmp(head, "HEAD"))
    detached_head = 1;

  /*
   * The remote must be configured.
   * This is to avoid pushing to the exact same URL as the parent.
   */
  remote = pushremote_get(argv[1]);
  if (!remote || remote->origin == REMOTE_UNCONFIGURED)
    die("remote '%s' not configured", argv[1]);

  /* Check the refspec */
  if (argc > 2) {
    int i;
    struct ref *local_refs = get_local_heads();
    struct refspec refspec = REFSPEC_INIT_PUSH;

    refspec_appendn(&refspec, argv + 2, argc - 2);

    for (i = 0; i < refspec.nr; i++) {
      const struct refspec_item *rs = &refspec.items[i];

      if (rs->pattern || rs->matching)
        continue;

      /* LHS must match a single ref */
      switch (count_refspec_match(rs->src, local_refs, NULL)) {
      case 1:
        break;
      case 0:
        /*
         * If LHS matches 'HEAD' then we need to ensure
         * that it matches the same named branch
         * checked out in the superproject.
         */
        if (!strcmp(rs->src, "HEAD")) {
          if (!detached_head &&
              !strcmp(head, superproject_head))
            break;
          die("HEAD does not match the named branch in the superproject");
        }
        /* fallthrough */
      default:
        die("src refspec '%s' must name a ref",
            rs->src);
      }
    }

    refspec_clear(&refspec);
    free_refs(local_refs);
  }
  free(head);

  return 0;
}

static int absorb_git_dirs(int argc, const char **argv, const char *prefix)
{
  int i;
  struct pathspec pathspec = { 0 };
  struct module_list list = MODULE_LIST_INIT;
  const char *super_prefix = NULL;
  struct option embed_gitdir_options[] = {
    OPT__SUPER_PREFIX(&super_prefix),
    OPT_END()
  };
  const char *const git_submodule_helper_usage[] = {
    N_("git submodule absorbgitdirs [<options>] [<path>...]"),
    NULL
  };
  int ret = 1;

  argc = parse_options(argc, argv, prefix, embed_gitdir_options,
           git_submodule_helper_usage, 0);

  if (module_list_compute(argv, prefix, &pathspec, &list) < 0)
    goto cleanup;

  for (i = 0; i < list.nr; i++)
    absorb_git_dir_into_superproject(list.entries[i]->name,
             super_prefix);

  ret = 0;
cleanup:
  clear_pathspec(&pathspec);
  module_list_release(&list);
  return ret;
}

static int module_set_url(int argc, const char **argv, const char *prefix)
{
  int quiet = 0, ret;
  const char *newurl;
  const char *path;
  char *config_name;
  struct option options[] = {
    OPT__QUIET(&quiet, N_("suppress output for setting url of a submodule")),
    OPT_END()
  };
  const char *const usage[] = {
    N_("git submodule set-url [--quiet] <path> <newurl>"),
    NULL
  };
  const struct submodule *sub;

  argc = parse_options(argc, argv, prefix, options, usage, 0);

  if (argc != 2 || !(path = argv[0]) || !(newurl = argv[1]))
    usage_with_options(usage, options);

  sub = submodule_from_path(the_repository, null_oid(), path);

  if (!sub)
    die(_("no submodule mapping found in .gitmodules for path '%s'"),
        path);

  config_name = xstrfmt("submodule.%s.url", sub->name);
  ret = config_set_in_gitmodules_file_gently(config_name, newurl);

  if (!ret) {
    repo_read_gitmodules(the_repository, 0);
    sync_submodule(sub->path, prefix, NULL, quiet ? OPT_QUIET : 0);
  }

  free(config_name);
  return !!ret;
}

static int module_set_branch(int argc, const char **argv, const char *prefix)
{
  int opt_default = 0, ret;
  const char *opt_branch = NULL;
  const char *path;
  char *config_name;
  struct option options[] = {
    /*
     * We accept the `quiet` option for uniformity across subcommands,
     * though there is nothing to make less verbose in this subcommand.
     */
    OPT_NOOP_NOARG('q', "quiet"),

    OPT_BOOL('d', "default", &opt_default,
      N_("set the default tracking branch to master")),
    OPT_STRING('b', "branch", &opt_branch, N_("branch"),
      N_("set the default tracking branch")),
    OPT_END()
  };
  const char *const usage[] = {
    N_("git submodule set-branch [-q|--quiet] (-d|--default) <path>"),
    N_("git submodule set-branch [-q|--quiet] (-b|--branch) <branch> <path>"),
    NULL
  };
  const struct submodule *sub;

  argc = parse_options(argc, argv, prefix, options, usage, 0);

  if (!opt_branch && !opt_default)
    die(_("--branch or --default required"));

  if (opt_branch && opt_default)
    die(_("options '%s' and '%s' cannot be used together"), "--branch", "--default");

  if (argc != 1 || !(path = argv[0]))
    usage_with_options(usage, options);

  sub = submodule_from_path(the_repository, null_oid(), path);

  if (!sub)
    die(_("no submodule mapping found in .gitmodules for path '%s'"),
        path);

  config_name = xstrfmt("submodule.%s.branch", sub->name);
  ret = config_set_in_gitmodules_file_gently(config_name, opt_branch);

  free(config_name);
  return !!ret;
}

static int module_create_branch(int argc, const char **argv, const char *prefix)
{
  enum branch_track track;
  int quiet = 0, force = 0, reflog = 0, dry_run = 0;
  struct option options[] = {
    OPT__QUIET(&quiet, N_("print only error messages")),
    OPT__FORCE(&force, N_("force creation"), 0),
    OPT_BOOL(0, "create-reflog", &reflog,
       N_("create the branch's reflog")),
    OPT_CALLBACK_F('t', "track",  &track, "(direct|inherit)",
      N_("set branch tracking configuration"),
      PARSE_OPT_OPTARG,
      parse_opt_tracking_mode),
    OPT__DRY_RUN(&dry_run,
           N_("show whether the branch would be created")),
    OPT_END()
  };
  const char *const usage[] = {
    N_("git submodule--helper create-branch [-f|--force] [--create-reflog] [-q|--quiet] [-t|--track] [-n|--dry-run] <name> <start-oid> <start-name>"),
    NULL
  };

  git_config(git_default_config, NULL);
  track = git_branch_track;
  argc = parse_options(argc, argv, prefix, options, usage, 0);

  if (argc != 3)
    usage_with_options(usage, options);

  if (!quiet && !dry_run)
    printf_ln(_("creating branch '%s'"), argv[0]);

  create_branches_recursively(the_repository, argv[0], argv[1], argv[2],
            force, reflog, quiet, track, dry_run);
  return 0;
}

struct add_data {
  const char *prefix;
  const char *branch;
  const char *reference_path;
  char *sm_path;
  const char *sm_name;
  const char *repo;
  const char *realrepo;
  enum ref_storage_format ref_storage_format;
  int depth;
  unsigned int force: 1;
  unsigned int quiet: 1;
  unsigned int progress: 1;
  unsigned int dissociate: 1;
};
#define ADD_DATA_INIT { \
  .depth = -1, \
  .ref_storage_format = REF_STORAGE_FORMAT_UNKNOWN, \
}

static void append_fetch_remotes(struct strbuf *msg, const char *git_dir_path)
{
  struct child_process cp_remote = CHILD_PROCESS_INIT;
  struct strbuf sb_remote_out = STRBUF_INIT;

  cp_remote.git_cmd = 1;
  strvec_pushf(&cp_remote.env,
         "GIT_DIR=%s", git_dir_path);
  strvec_push(&cp_remote.env, "GIT_WORK_TREE=.");
  strvec_pushl(&cp_remote.args, "remote", "-v", NULL);
  if (!capture_command(&cp_remote, &sb_remote_out, 0)) {
    char *next_line;
    char *line = sb_remote_out.buf;

    while ((next_line = strchr(line, '\n')) != NULL) {
      size_t len = next_line - line;

      if (strip_suffix_mem(line, &len, " (fetch)"))
        strbuf_addf(msg, "  %.*s\n", (int)len, line);
      line = next_line + 1;
    }
  }

  strbuf_release(&sb_remote_out);
}

static int add_submodule(const struct add_data *add_data)
{
  char *submod_gitdir_path;
  struct module_clone_data clone_data = MODULE_CLONE_DATA_INIT;
  struct string_list reference = STRING_LIST_INIT_NODUP;
  int ret = -1;

  /* perhaps the path already exists and is already a git repo, else clone it */
  if (is_directory(add_data->sm_path)) {
    struct strbuf sm_path = STRBUF_INIT;
    strbuf_addstr(&sm_path, add_data->sm_path);
    submod_gitdir_path = xstrfmt("%s/.git", add_data->sm_path);
    if (is_nonbare_repository_dir(&sm_path))
      printf(_("Adding existing repo at '%s' to the index\n"),
             add_data->sm_path);
    else
      die(_("'%s' already exists and is not a valid git repo"),
          add_data->sm_path);
    strbuf_release(&sm_path);
    free(submod_gitdir_path);
  } else {
    struct child_process cp = CHILD_PROCESS_INIT;

    submod_gitdir_path = xstrfmt(".git/modules/%s", add_data->sm_name);

    if (is_directory(submod_gitdir_path)) {
      if (!add_data->force) {
        struct strbuf msg = STRBUF_INIT;
        char *die_msg;

        strbuf_addf(&msg, _("A git directory for '%s' is found "
                "locally with remote(s):\n"),
              add_data->sm_name);

        append_fetch_remotes(&msg, submod_gitdir_path);
        free(submod_gitdir_path);

        strbuf_addf(&msg, _("If you want to reuse this local git "
                "directory instead of cloning again from\n"
                "  %s\n"
                "use the '--force' option. If the local git "
                "directory is not the correct repo\n"
                "or you are unsure what this means choose "
                "another name with the '--name' option."),
              add_data->realrepo);

        die_msg = strbuf_detach(&msg, NULL);
        die("%s", die_msg);
      } else {
        printf(_("Reactivating local git directory for "
           "submodule '%s'\n"), add_data->sm_name);
      }
    }
    free(submod_gitdir_path);

    clone_data.prefix = add_data->prefix;
    clone_data.path = add_data->sm_path;
    clone_data.name = add_data->sm_name;
    clone_data.url = add_data->realrepo;
    clone_data.quiet = add_data->quiet;
    clone_data.progress = add_data->progress;
    if (add_data->reference_path) {
      char *p = xstrdup(add_data->reference_path);

      string_list_append(&reference, p)->util = p;
    }
    clone_data.ref_storage_format = add_data->ref_storage_format;
    clone_data.dissociate = add_data->dissociate;
    if (add_data->depth >= 0)
      clone_data.depth = add_data->depth;

    if (clone_submodule(&clone_data, &reference))
      goto cleanup;

    prepare_submodule_repo_env(&cp.env);
    cp.git_cmd = 1;
    cp.dir = add_data->sm_path;
    /*
     * NOTE: we only get here if add_data->force is true, so
     * passing --force to checkout is reasonable.
     */
    strvec_pushl(&cp.args, "checkout", "-f", "-q", NULL);

    if (add_data->branch) {
      strvec_pushl(&cp.args, "-B", add_data->branch, NULL);
      strvec_pushf(&cp.args, "origin/%s", add_data->branch);
    }

    if (run_command(&cp))
      die(_("unable to checkout submodule '%s'"), add_data->sm_path);
  }
  ret = 0;

cleanup:
  string_list_clear(&reference, 1);
  return ret;
}

static int config_submodule_in_gitmodules(const char *name, const char *var, const char *value)
{
  char *key;
  int ret;

  if (!is_writing_gitmodules_ok())
    die(_("please make sure that the .gitmodules file is in the working tree"));

  key = xstrfmt("submodule.%s.%s", name, var);
  ret = config_set_in_gitmodules_file_gently(key, value);
  free(key);

  return ret;
}

static void configure_added_submodule(struct add_data *add_data)
{
  char *key;
  struct child_process add_submod = CHILD_PROCESS_INIT;
  struct child_process add_gitmodules = CHILD_PROCESS_INIT;

  key = xstrfmt("submodule.%s.url", add_data->sm_name);
  git_config_set_gently(key, add_data->realrepo);
  free(key);

  add_submod.git_cmd = 1;
  strvec_pushl(&add_submod.args, "add",
         "--no-warn-embedded-repo", NULL);
  if (add_data->force)
    strvec_push(&add_submod.args, "--force");
  strvec_pushl(&add_submod.args, "--", add_data->sm_path, NULL);

  if (run_command(&add_submod))
    die(_("Failed to add submodule '%s'"), add_data->sm_path);

  if (config_submodule_in_gitmodules(add_data->sm_name, "path", add_data->sm_path) ||
      config_submodule_in_gitmodules(add_data->sm_name, "url", add_data->repo))
    die(_("Failed to register submodule '%s'"), add_data->sm_path);

  if (add_data->branch) {
    if (config_submodule_in_gitmodules(add_data->sm_name,
               "branch", add_data->branch))
      die(_("Failed to register submodule '%s'"), add_data->sm_path);
  }

  add_gitmodules.git_cmd = 1;
  strvec_pushl(&add_gitmodules.args,
         "add", "--force", "--", ".gitmodules", NULL);

  if (run_command(&add_gitmodules))
    die(_("Failed to register submodule '%s'"), add_data->sm_path);

  /*
   * NEEDSWORK: In a multi-working-tree world this needs to be
   * set in the per-worktree config.
   */
  /*
   * NEEDSWORK: In the longer run, we need to get rid of this
   * pattern of querying "submodule.active" before calling
   * is_submodule_active(), since that function needs to find
   * out the value of "submodule.active" again anyway.
   */
  if (!git_config_get("submodule.active")) {
    /*
     * If the submodule being added isn't already covered by the
     * current configured pathspec, set the submodule's active flag
     */
    if (!is_submodule_active(the_repository, add_data->sm_path)) {
      key = xstrfmt("submodule.%s.active", add_data->sm_name);
      git_config_set_gently(key, "true");
      free(key);
    }
  } else {
    key = xstrfmt("submodule.%s.active", add_data->sm_name);
    git_config_set_gently(key, "true");
    free(key);
  }
}

static void die_on_index_match(const char *path, int force)
{
  struct pathspec ps;
  const char *args[] = { path, NULL };
  parse_pathspec(&ps, 0, PATHSPEC_PREFER_CWD, NULL, args);

  if (repo_read_index_preload(the_repository, NULL, 0) < 0)
    die(_("index file corrupt"));

  if (ps.nr) {
    int i;
    char *ps_matched = xcalloc(ps.nr, 1);

    /* TODO: audit for interaction with sparse-index. */
    ensure_full_index(the_repository->index);

    /*
     * Since there is only one pathspec, we just need to
     * check ps_matched[0] to know if a cache entry matched.
     */
    for (i = 0; i < the_repository->index->cache_nr; i++) {
      ce_path_match(the_repository->index, the_repository->index->cache[i], &ps,
              ps_matched);

      if (ps_matched[0]) {
        if (!force)
          die(_("'%s' already exists in the index"),
              path);
        if (!S_ISGITLINK(the_repository->index->cache[i]->ce_mode))
          die(_("'%s' already exists in the index "
                "and is not a submodule"), path);
        break;
      }
    }
    free(ps_matched);
  }
  clear_pathspec(&ps);
}

static void die_on_repo_without_commits(const char *path)
{
  struct strbuf sb = STRBUF_INIT;
  strbuf_addstr(&sb, path);
  if (is_nonbare_repository_dir(&sb)) {
    struct object_id oid;
    if (repo_resolve_gitlink_ref(the_repository, path, "HEAD", &oid) < 0)
      die(_("'%s' does not have a commit checked out"), path);
  }
  strbuf_release(&sb);
}

static int module_add(int argc, const char **argv, const char *prefix)
{
  int force = 0, quiet = 0, progress = 0, dissociate = 0;
  struct add_data add_data = ADD_DATA_INIT;
  const char *ref_storage_format = NULL;
  char *to_free = NULL;
  struct option options[] = {
    OPT_STRING('b', "branch", &add_data.branch, N_("branch"),
         N_("branch of repository to add as submodule")),
    OPT__FORCE(&force, N_("allow adding an otherwise ignored submodule path"),
         PARSE_OPT_NOCOMPLETE),
    OPT__QUIET(&quiet, N_("print only error messages")),
    OPT_BOOL(0, "progress", &progress, N_("force cloning progress")),
    OPT_STRING(0, "reference", &add_data.reference_path, N_("repository"),
         N_("reference repository")),
    OPT_STRING(0, "ref-format", &ref_storage_format, N_("format"),
         N_("specify the reference format to use")),
    OPT_BOOL(0, "dissociate", &dissociate, N_("borrow the objects from reference repositories")),
    OPT_STRING(0, "name", &add_data.sm_name, N_("name"),
         N_("sets the submodule's name to the given string "
            "instead of defaulting to its path")),
    OPT_INTEGER(0, "depth", &add_data.depth, N_("depth for shallow clones")),
    OPT_END()
  };
  const char *const usage[] = {
    N_("git submodule add [<options>] [--] <repository> [<path>]"),
    NULL
  };
  struct strbuf sb = STRBUF_INIT;
  int ret = 1;

  argc = parse_options(argc, argv, prefix, options, usage, 0);

  if (!is_writing_gitmodules_ok())
    die(_("please make sure that the .gitmodules file is in the working tree"));

  if (prefix && *prefix &&
      add_data.reference_path && !is_absolute_path(add_data.reference_path))
    add_data.reference_path = xstrfmt("%s%s", prefix, add_data.reference_path);

  if (argc == 0 || argc > 2)
    usage_with_options(usage, options);

  if (ref_storage_format) {
    add_data.ref_storage_format = ref_storage_format_by_name(ref_storage_format);
    if (add_data.ref_storage_format == REF_STORAGE_FORMAT_UNKNOWN)
      die(_("unknown ref storage format '%s'"), ref_storage_format);
  }

  add_data.repo = argv[0];
  if (argc == 1)
    add_data.sm_path = git_url_basename(add_data.repo, 0, 0);
  else
    add_data.sm_path = xstrdup(argv[1]);

  if (prefix && *prefix && !is_absolute_path(add_data.sm_path)) {
    char *sm_path = add_data.sm_path;

    add_data.sm_path = xstrfmt("%s%s", prefix, sm_path);
    free(sm_path);
  }

  if (starts_with_dot_dot_slash(add_data.repo) ||
      starts_with_dot_slash(add_data.repo)) {
    if (prefix)
      die(_("Relative path can only be used from the toplevel "
            "of the working tree"));

    /* dereference source url relative to parent's url */
    to_free = resolve_relative_url(add_data.repo, NULL, 1);
    add_data.realrepo = to_free;
  } else if (is_dir_sep(add_data.repo[0]) || strchr(add_data.repo, ':')) {
    add_data.realrepo = add_data.repo;
  } else {
    die(_("repo URL: '%s' must be absolute or begin with ./|../"),
        add_data.repo);
  }

  /*
   * normalize path:
   * multiple //; leading ./; /./; /../;
   */
  normalize_path_copy(add_data.sm_path, add_data.sm_path);
  strip_dir_trailing_slashes(add_data.sm_path);

  if (validate_submodule_path(add_data.sm_path) < 0)
    exit(128);

  die_on_index_match(add_data.sm_path, force);
  die_on_repo_without_commits(add_data.sm_path);

  if (!force) {
    struct child_process cp = CHILD_PROCESS_INIT;

    cp.git_cmd = 1;
    cp.no_stdout = 1;
    strvec_pushl(&cp.args, "add", "--dry-run", "--ignore-missing",
           "--no-warn-embedded-repo", add_data.sm_path, NULL);
    if ((ret = pipe_command(&cp, NULL, 0, NULL, 0, &sb, 0))) {
      strbuf_complete_line(&sb);
      fputs(sb.buf, stderr);
      goto cleanup;
    }
  }

  if(!add_data.sm_name)
    add_data.sm_name = add_data.sm_path;

  if (check_submodule_name(add_data.sm_name))
    die(_("'%s' is not a valid submodule name"), add_data.sm_name);

  add_data.prefix = prefix;
  add_data.force = !!force;
  add_data.quiet = !!quiet;
  add_data.progress = !!progress;
  add_data.dissociate = !!dissociate;

  if (add_submodule(&add_data))
    goto cleanup;
  configure_added_submodule(&add_data);

  ret = 0;
cleanup:
  free(add_data.sm_path);
  free(to_free);
  strbuf_release(&sb);

  return ret;
}

int cmd_submodule__helper(int argc, const char **argv, const char *prefix)
{
  parse_opt_subcommand_fn *fn = NULL;
  const char *const usage[] = {
    N_("git submodule--helper <command>"),
    NULL
  };
  struct option options[] = {
    OPT_SUBCOMMAND("clone", &fn, module_clone),
    OPT_SUBCOMMAND("add", &fn, module_add),
    OPT_SUBCOMMAND("update", &fn, module_update),
    OPT_SUBCOMMAND("foreach", &fn, module_foreach),
    OPT_SUBCOMMAND("init", &fn, module_init),
    OPT_SUBCOMMAND("status", &fn, module_status),
    OPT_SUBCOMMAND("sync", &fn, module_sync),
    OPT_SUBCOMMAND("deinit", &fn, module_deinit),
    OPT_SUBCOMMAND("summary", &fn, module_summary),
    OPT_SUBCOMMAND("push-check", &fn, push_check),
    OPT_SUBCOMMAND("absorbgitdirs", &fn, absorb_git_dirs),
    OPT_SUBCOMMAND("set-url", &fn, module_set_url),
    OPT_SUBCOMMAND("set-branch", &fn, module_set_branch),
    OPT_SUBCOMMAND("create-branch", &fn, module_create_branch),
    OPT_END()
  };
  argc = parse_options(argc, argv, prefix, options, usage, 0);

  return fn(argc, argv, prefix);
}

Coverage Report

Created: 2024-09-16 06:10