#include "git-compat-util.h"

#include "abspath.h"

#include "repository.h"

#include "object-store-ll.h"

#include "config.h"

#include "object.h"

#include "lockfile.h"

#include "path.h"

#include "read-cache-ll.h"

#include "remote.h"

#include "setup.h"

#include "loose.h"

#include "submodule-config.h"

#include "sparse-index.h"

#include "trace2.h"

#include "promisor-remote.h"

#include "refs.h"

/*

 * We do not define `USE_THE_REPOSITORY_VARIABLE` in this file because we do

 * not want to rely on functions that implicitly use `the_repository`. This

 * means that the `extern` declaration of `the_repository` isn't visible here,

 * which makes sparse unhappy. We thus declare it here.

 */

extern struct repository *the_repository;

/* The main repository */

static struct repository the_repo;

struct repository *the_repository = &the_repo;

/*

 * An escape hatch: if we hit a bug in the production code that fails

 * to set an appropriate hash algorithm (most likely to happen when

 * running outside a repository), we can tell the user who reported

 * the crash to set the environment variable to "sha1" (all lowercase)

 * to revert to the historical behaviour of defaulting to SHA-1.

 */

static void set_default_hash_algo(struct repository *repo)

{

  const char *hash_name;

  int algo;

  hash_name = getenv("GIT_TEST_DEFAULT_HASH_ALGO");

  if (!hash_name)

    return;

  algo = hash_algo_by_name(hash_name);

  if (algo == GIT_HASH_UNKNOWN)

    return;

  repo_set_hash_algo(repo, algo);

}

void initialize_repository(struct repository *repo)

{

  repo->objects = raw_object_store_new();

  repo->remote_state = remote_state_new();

  repo->parsed_objects = parsed_object_pool_new();

  ALLOC_ARRAY(repo->index, 1);

  index_state_init(repo->index, repo);

  /*

   * When a command runs inside a repository, it learns what

   * hash algorithm is in use from the repository, but some

   * commands are designed to work outside a repository, yet

   * they want to access the_hash_algo, if only for the length

   * of the hashed value to see if their input looks like a

   * plausible hash value.

   *

   * We are in the process of identifying such code paths and

   * giving them an appropriate default individually; any

   * unconverted code paths that try to access the_hash_algo

   * will thus fail.  The end-users however have an escape hatch

   * to set GIT_TEST_DEFAULT_HASH_ALGO environment variable to

   * "sha1" to get back the old behaviour of defaulting to SHA-1.

   *

   * This escape hatch is deliberately kept unadvertised, so

   * that they see crashes and we can get a report before

   * telling them about it.

   */

  if (repo == the_repository)

    set_default_hash_algo(repo);

}

static void expand_base_dir(char **out, const char *in,

          const char *base_dir, const char *def_in)

{

  free(*out);

  if (in)

    *out = xstrdup(in);

  else

    *out = xstrfmt("%s/%s", base_dir, def_in);

}

static void repo_set_commondir(struct repository *repo,

             const char *commondir)

{

  struct strbuf sb = STRBUF_INIT;

  free(repo->commondir);

  if (commondir) {

    repo->different_commondir = 1;

    repo->commondir = xstrdup(commondir);

    return;

  }

  repo->different_commondir = get_common_dir_noenv(&sb, repo->gitdir);

  repo->commondir = strbuf_detach(&sb, NULL);

}

void repo_set_gitdir(struct repository *repo,

         const char *root,

         const struct set_gitdir_args *o)

{

  const char *gitfile = read_gitfile(root);

  /*

   * repo->gitdir is saved because the caller could pass "root"

   * that also points to repo->gitdir. We want to keep it alive

   * until after xstrdup(root). Then we can free it.

   */

  char *old_gitdir = repo->gitdir;

  repo->gitdir = xstrdup(gitfile ? gitfile : root);

  free(old_gitdir);

  repo_set_commondir(repo, o->commondir);

  if (!repo->objects->odb) {

    CALLOC_ARRAY(repo->objects->odb, 1);

    repo->objects->odb_tail = &repo->objects->odb->next;

  }

  expand_base_dir(&repo->objects->odb->path, o->object_dir,

      repo->commondir, "objects");

  repo->objects->odb->disable_ref_updates = o->disable_ref_updates;

  free(repo->objects->alternate_db);

  repo->objects->alternate_db = xstrdup_or_null(o->alternate_db);

  expand_base_dir(&repo->graft_file, o->graft_file,

      repo->commondir, "info/grafts");

  expand_base_dir(&repo->index_file, o->index_file,

      repo->gitdir, "index");

}

void repo_set_hash_algo(struct repository *repo, int hash_algo)

{

  repo->hash_algo = &hash_algos[hash_algo];

}

void repo_set_compat_hash_algo(struct repository *repo, int algo)

{

  if (hash_algo_by_ptr(repo->hash_algo) == algo)

    BUG("hash_algo and compat_hash_algo match");

  repo->compat_hash_algo = algo ? &hash_algos[algo] : NULL;

  if (repo->compat_hash_algo)

    repo_read_loose_object_map(repo);

}

void repo_set_ref_storage_format(struct repository *repo,

         enum ref_storage_format format)

{

  repo->ref_storage_format = format;

}

/*

 * Attempt to resolve and set the provided 'gitdir' for repository 'repo'.

 * Return 0 upon success and a non-zero value upon failure.

 */

static int repo_init_gitdir(struct repository *repo, const char *gitdir)

{

  int ret = 0;

  int error = 0;

  char *abspath = NULL;

  const char *resolved_gitdir;

  struct set_gitdir_args args = { NULL };

  abspath = real_pathdup(gitdir, 0);

  if (!abspath) {

    ret = -1;

    goto out;

  }

  /* 'gitdir' must reference the gitdir directly */

  resolved_gitdir = resolve_gitdir_gently(abspath, &error);

  if (!resolved_gitdir) {

    ret = -1;

    goto out;

  }

  repo_set_gitdir(repo, resolved_gitdir, &args);

out:

  free(abspath);

  return ret;

}

void repo_set_worktree(struct repository *repo, const char *path)

{

  repo->worktree = real_pathdup(path, 1);

  trace2_def_repo(repo);

}

static int read_and_verify_repository_format(struct repository_format *format,

               const char *commondir)

{

  int ret = 0;

  struct strbuf sb = STRBUF_INIT;

  strbuf_addf(&sb, "%s/config", commondir);

  read_repository_format(format, sb.buf);

  strbuf_reset(&sb);

  if (verify_repository_format(format, &sb) < 0) {

    warning("%s", sb.buf);

    ret = -1;

  }

  strbuf_release(&sb);

  return ret;

}

/*

 * Initialize 'repo' based on the provided 'gitdir'.

 * Return 0 upon success and a non-zero value upon failure.

 */

int repo_init(struct repository *repo,

        const char *gitdir,

        const char *worktree)

{

  struct repository_format format = REPOSITORY_FORMAT_INIT;

  memset(repo, 0, sizeof(*repo));

  initialize_repository(repo);

  if (repo_init_gitdir(repo, gitdir))

    goto error;

  if (read_and_verify_repository_format(&format, repo->commondir))

    goto error;

  repo_set_hash_algo(repo, format.hash_algo);

  repo_set_compat_hash_algo(repo, format.compat_hash_algo);

  repo_set_ref_storage_format(repo, format.ref_storage_format);

  repo->repository_format_worktree_config = format.worktree_config;

  /* take ownership of format.partial_clone */

  repo->repository_format_partial_clone = format.partial_clone;

  format.partial_clone = NULL;

  if (worktree)

    repo_set_worktree(repo, worktree);

  if (repo->compat_hash_algo)

    repo_read_loose_object_map(repo);

  clear_repository_format(&format);

  return 0;

error:

  repo_clear(repo);

  return -1;

}

int repo_submodule_init(struct repository *subrepo,

      struct repository *superproject,

      const char *path,

      const struct object_id *treeish_name)

{

  struct strbuf gitdir = STRBUF_INIT;

  struct strbuf worktree = STRBUF_INIT;

  int ret = 0;

  strbuf_repo_worktree_path(&gitdir, superproject, "%s/.git", path);

  strbuf_repo_worktree_path(&worktree, superproject, "%s", path);

  if (repo_init(subrepo, gitdir.buf, worktree.buf)) {

    /*

     * If initialization fails then it may be due to the submodule

     * not being populated in the superproject's worktree.  Instead

     * we can try to initialize the submodule by finding it's gitdir

     * in the superproject's 'modules' directory.  In this case the

     * submodule would not have a worktree.

     */

    const struct submodule *sub =

      submodule_from_path(superproject, treeish_name, path);

    if (!sub) {

      ret = -1;

      goto out;

    }

    strbuf_reset(&gitdir);

    submodule_name_to_gitdir(&gitdir, superproject, sub->name);

    if (repo_init(subrepo, gitdir.buf, NULL)) {

      ret = -1;

      goto out;

    }

  }

  subrepo->submodule_prefix = xstrfmt("%s%s/",

              superproject->submodule_prefix ?

              superproject->submodule_prefix :

              "", path);

out:

  strbuf_release(&gitdir);

  strbuf_release(&worktree);

  return ret;

}

static void repo_clear_path_cache(struct repo_path_cache *cache)

{

  FREE_AND_NULL(cache->squash_msg);

  FREE_AND_NULL(cache->squash_msg);

  FREE_AND_NULL(cache->merge_msg);

  FREE_AND_NULL(cache->merge_rr);

  FREE_AND_NULL(cache->merge_mode);

  FREE_AND_NULL(cache->merge_head);

  FREE_AND_NULL(cache->fetch_head);

  FREE_AND_NULL(cache->shallow);

}

void repo_clear(struct repository *repo)

{

  struct hashmap_iter iter;

  struct strmap_entry *e;

  FREE_AND_NULL(repo->gitdir);

  FREE_AND_NULL(repo->commondir);

  FREE_AND_NULL(repo->graft_file);

  FREE_AND_NULL(repo->index_file);

  FREE_AND_NULL(repo->worktree);

  FREE_AND_NULL(repo->submodule_prefix);

  raw_object_store_clear(repo->objects);

  FREE_AND_NULL(repo->objects);

  parsed_object_pool_clear(repo->parsed_objects);

  FREE_AND_NULL(repo->parsed_objects);

  FREE_AND_NULL(repo->settings.fsmonitor);

  if (repo->config) {

    git_configset_clear(repo->config);

    FREE_AND_NULL(repo->config);

  }

  if (repo->submodule_cache) {

    submodule_cache_free(repo->submodule_cache);

    repo->submodule_cache = NULL;

  }

  if (repo->index) {

    discard_index(repo->index);

    FREE_AND_NULL(repo->index);

  }

  if (repo->promisor_remote_config) {

    promisor_remote_clear(repo->promisor_remote_config);

    FREE_AND_NULL(repo->promisor_remote_config);

  }

  if (repo->remote_state) {

    remote_state_clear(repo->remote_state);

    FREE_AND_NULL(repo->remote_state);

  }

  strmap_for_each_entry(&repo->submodule_ref_stores, &iter, e)

    ref_store_release(e->value);

  strmap_clear(&repo->submodule_ref_stores, 1);

  strmap_for_each_entry(&repo->worktree_ref_stores, &iter, e)

    ref_store_release(e->value);

  strmap_clear(&repo->worktree_ref_stores, 1);

  repo_clear_path_cache(&repo->cached_paths);

}

int repo_read_index(struct repository *repo)

{

  int res;

  /* Complete the double-reference */

  if (!repo->index) {

    ALLOC_ARRAY(repo->index, 1);

    index_state_init(repo->index, repo);

  } else if (repo->index->repo != repo) {

    BUG("repo's index should point back at itself");

  }

  res = read_index_from(repo->index, repo->index_file, repo->gitdir);

  prepare_repo_settings(repo);

  if (repo->settings.command_requires_full_index)

    ensure_full_index(repo->index);

  /*

   * If sparse checkouts are in use, check whether paths with the

   * SKIP_WORKTREE attribute are missing from the worktree; if not,

   * clear that attribute for that path.

   */

  clear_skip_worktree_from_present_files(repo->index);

  return res;

}

int repo_hold_locked_index(struct repository *repo,

         struct lock_file *lf,

         int flags)

{

  if (!repo->index_file)

    BUG("the repo hasn't been setup");

  return hold_lock_file_for_update(lf, repo->index_file, flags);

}