/*
 * Copyright (C) the libgit2 contributors. All rights reserved.
 *
 * This file is part of libgit2, distributed under the GNU GPL v2 with
 * a Linking Exception. For full terms see the included COPYING file.
 */
#include "common.h"
#include "git2/config.h"
#include "git2/sys/config.h"
#include "git2/types.h"
#include "git2/index.h"
#include "buffer.h"
#include "buf_text.h"
#include "vector.h"
#include "posix.h"
#include "config_file.h"
#include "config.h"
#include "repository.h"
#include "submodule.h"
#include "tree.h"
#include "iterator.h"
#include "path.h"
#include "index.h"
#define GIT_MODULES_FILE ".gitmodules"
static git_cvar_map _sm_update_map[] = {
        {GIT_CVAR_STRING, "checkout", GIT_SUBMODULE_UPDATE_CHECKOUT},
        {GIT_CVAR_STRING, "rebase", GIT_SUBMODULE_UPDATE_REBASE},
        {GIT_CVAR_STRING, "merge", GIT_SUBMODULE_UPDATE_MERGE},
        {GIT_CVAR_STRING, "none", GIT_SUBMODULE_UPDATE_NONE},
        {GIT_CVAR_FALSE, NULL, GIT_SUBMODULE_UPDATE_NONE},
        {GIT_CVAR_TRUE, NULL, GIT_SUBMODULE_UPDATE_CHECKOUT},
};
static git_cvar_map _sm_ignore_map[] = {
        {GIT_CVAR_STRING, "none", GIT_SUBMODULE_IGNORE_NONE},
        {GIT_CVAR_STRING, "untracked", GIT_SUBMODULE_IGNORE_UNTRACKED},
        {GIT_CVAR_STRING, "dirty", GIT_SUBMODULE_IGNORE_DIRTY},
        {GIT_CVAR_STRING, "all", GIT_SUBMODULE_IGNORE_ALL},
        {GIT_CVAR_FALSE, NULL, GIT_SUBMODULE_IGNORE_NONE},
        {GIT_CVAR_TRUE, NULL, GIT_SUBMODULE_IGNORE_ALL},
};
static git_cvar_map _sm_recurse_map[] = {
        {GIT_CVAR_STRING, "on-demand", GIT_SUBMODULE_RECURSE_ONDEMAND},
        {GIT_CVAR_FALSE, NULL, GIT_SUBMODULE_RECURSE_NO},
        {GIT_CVAR_TRUE, NULL, GIT_SUBMODULE_RECURSE_YES},
};
enum {
        CACHE_OK = 0,
        CACHE_REFRESH = 1,
        CACHE_FLUSH = 2
};
enum {
        GITMODULES_EXISTING = 0,
        GITMODULES_CREATE = 1,
};
static kh_inline khint_t str_hash_no_trailing_slash(const char *s)
{
        khint_t h;
        for (h = 0; *s; ++s)
                if (s[1] != '\0' || *s != '/')
                        h = (h << 5) - h + *s;
        return h;
}
static kh_inline int str_equal_no_trailing_slash(const char *a, const char *b)
{
        size_t alen = a ? strlen(a) : 0;
        size_t blen = b ? strlen(b) : 0;
        if (alen > 0 && a[alen - 1] == '/')
                alen--;
        if (blen > 0 && b[blen - 1] == '/')
                blen--;
        return (alen == blen && strncmp(a, b, alen) == 0);
}
__KHASH_IMPL(
        str, static kh_inline, const char *, void *, 1,
        str_hash_no_trailing_slash, str_equal_no_trailing_slash)
static int submodule_alloc(git_submodule **out, git_repository *repo, const char *name);
static git_config_backend *open_gitmodules(git_repository *repo, int gitmod);
static git_config *gitmodules_snapshot(git_repository *repo);
static int get_url_base(git_buf *url, git_repository *repo);
static int lookup_head_remote_key(git_buf *remote_key, git_repository *repo);
static int submodule_load_each(const git_config_entry *entry, void *payload);
static int submodule_read_config(git_submodule *sm, git_config *cfg);
static int submodule_load_from_wd_lite(git_submodule *);
static void submodule_get_index_status(unsigned int *, git_submodule *);
static void submodule_get_wd_status(unsigned int *, git_submodule *, git_repository *, git_submodule_ignore_t);
static void submodule_update_from_index_entry(git_submodule *sm, const git_index_entry *ie);
static void submodule_update_from_head_data(git_submodule *sm, mode_t mode, const git_oid *id);
static int submodule_cmp(const void *a, const void *b)
{
        return strcmp(((git_submodule *)a)->name, ((git_submodule *)b)->name);
}
static int submodule_config_key_trunc_puts(git_buf *key, const char *suffix)
{
        ssize_t idx = git_buf_rfind(key, '.');
        git_buf_truncate(key, (size_t)(idx + 1));
        return git_buf_puts(key, suffix);
}
/*
 * PUBLIC APIS
 */
static void submodule_set_lookup_error(int error, const char *name)
{
        if (!error)
                return;
        giterr_set(GITERR_SUBMODULE, (error == GIT_ENOTFOUND) ?
                "No submodule named '%s'" :
                "Submodule '%s' has not been added yet", name);
}
typedef struct {
        const char *path;
        char *name;
} fbp_data;
static int find_by_path(const git_config_entry *entry, void *payload)
{
        fbp_data *data = payload;
        if (!strcmp(entry->value, data->path)) {
                const char *fdot, *ldot;
                fdot = strchr(entry->name, '.');
                ldot = strrchr(entry->name, '.');
                data->name = git__strndup(fdot + 1, ldot - fdot - 1);
                GITERR_CHECK_ALLOC(data->name);
        }
        return 0;
}
/**
 * Find out the name of a submodule from its path
 */
static int name_from_path(git_buf *out, git_config *cfg, const char *path)
{
        const char *key = "submodule\\..*\\.path";
        git_config_iterator *iter;
        git_config_entry *entry;
        int error;
        if ((error = git_config_iterator_glob_new(&iter, cfg, key)) < 0)
                return error;
        while ((error = git_config_next(&entry, iter)) == 0) {
                const char *fdot, *ldot;
                /* TODO: this should maybe be strcasecmp on a case-insensitive fs */
                if (strcmp(path, entry->value) != 0)
                        continue;
                fdot = strchr(entry->name, '.');
                ldot = strrchr(entry->name, '.');
                git_buf_clear(out);
                git_buf_put(out, fdot + 1, ldot - fdot - 1);
                goto cleanup;
        }
        if (error == GIT_ITEROVER) {
                giterr_set(GITERR_SUBMODULE, "could not find a submodule name for '%s'", path);
                error = GIT_ENOTFOUND;
        }
cleanup:
        git_config_iterator_free(iter);
        return error;
}
int git_submodule_lookup(
        git_submodule **out, /* NULL if user only wants to test existence */
        git_repository *repo,
        const char *name)    /* trailing slash is allowed */
{
        int error;
        unsigned int location;
        git_submodule *sm;
        assert(repo && name);
        if ((error = submodule_alloc(&sm, repo, name)) < 0)
                return error;
        if ((error = git_submodule_reload(sm, false)) < 0) {
                git_submodule_free(sm);
                return error;
        }
        if ((error = git_submodule_location(&location, sm)) < 0) {
                git_submodule_free(sm);
                return error;
        }
        /* If it's not configured or we're looking by path  */
        if (location == 0 || location == GIT_SUBMODULE_STATUS_IN_WD) {
                git_config_backend *mods;
                const char *pattern = "submodule\\..*\\.path";
                git_buf path = GIT_BUF_INIT;
                fbp_data data = { NULL, NULL };
                git_buf_puts(&path, name);
                while (path.ptr[path.size-1] == '/') {
                        path.ptr[--path.size] = '\0';
                }
                data.path = path.ptr;
                mods = open_gitmodules(repo, GITMODULES_EXISTING);
                if (mods)
                        error = git_config_file_foreach_match(mods, pattern, find_by_path, &data);
                git_config_file_free(mods);
                if (error < 0) {
                        git_submodule_free(sm);
                        git_buf_free(&path);
                        return error;
                }
                if (data.name) {
                        git__free(sm->name);
                        sm->name = data.name;
                        sm->path = git_buf_detach(&path);
                        /* Try to load again with the right name */
                        if ((error = git_submodule_reload(sm, false)) < 0) {
                                git_submodule_free(sm);
                                return error;
                        }
                }
                git_buf_free(&path);
        }
        if ((error = git_submodule_location(&location, sm)) < 0) {
                git_submodule_free(sm);
                return error;
        }
        /* If we still haven't found it, do the WD check */
        if (location == 0 || location == GIT_SUBMODULE_STATUS_IN_WD) {
                git_submodule_free(sm);
                error = GIT_ENOTFOUND;
                /* If it's not configured, we still check if there's a repo at the path */
                if (git_repository_workdir(repo)) {
                        git_buf path = GIT_BUF_INIT;
                        if (git_buf_join3(&path,
                                          '/', git_repository_workdir(repo), name, DOT_GIT) < 0)
                                return -1;
                        if (git_path_exists(path.ptr))
                                error = GIT_EEXISTS;
                        git_buf_free(&path);
                }
                submodule_set_lookup_error(error, name);
                return error;
        }
        if (out)
                *out = sm;
        else
                git_submodule_free(sm);
        return 0;
}
static void submodule_free_dup(void *sm)
{
        git_submodule_free(sm);
}
static int submodule_get_or_create(git_submodule **out, git_repository *repo, git_strmap *map, const char *name)
{
        int error = 0;
        khiter_t pos;
        git_submodule *sm = NULL;
        pos = git_strmap_lookup_index(map, name);
        if (git_strmap_valid_index(map, pos)) {
                sm = git_strmap_value_at(map, pos);
                goto done;
        }
        /* if the submodule doesn't exist yet in the map, create it */
        if ((error = submodule_alloc(&sm, repo, name)) < 0)
                return error;
        pos = kh_put(str, map, sm->name, &error);
        /* nobody can beat us to adding it */
        assert(error != 0);
        if (error < 0) {
                git_submodule_free(sm);
                return error;
        }
        git_strmap_set_value_at(map, pos, sm);
done:
        GIT_REFCOUNT_INC(sm);
        *out = sm;
        return 0;
}
static int submodules_from_index(git_strmap *map, git_index *idx, git_config *cfg)
{
       int error;
       git_iterator *i;
       const git_index_entry *entry;
       git_buf name = GIT_BUF_INIT;
       if ((error = git_iterator_for_index(&i, idx, NULL)) < 0)
               return error;
       while (!(error = git_iterator_advance(&entry, i))) {
               khiter_t pos = git_strmap_lookup_index(map, entry->path);
               git_submodule *sm;
               git_buf_clear(&name);
               if (!name_from_path(&name, cfg, entry->path)) {
                       git_strmap_lookup_index(map, name.ptr);
               }
               if (git_strmap_valid_index(map, pos)) {
                       sm = git_strmap_value_at(map, pos);
                       if (S_ISGITLINK(entry->mode))
                               submodule_update_from_index_entry(sm, entry);
                       else
                               sm->flags |= GIT_SUBMODULE_STATUS__INDEX_NOT_SUBMODULE;
               } else if (S_ISGITLINK(entry->mode)) {
                       if (!submodule_get_or_create(&sm, git_index_owner(idx), map, name.ptr ? name.ptr : entry->path)) {
                               submodule_update_from_index_entry(sm, entry);
                               git_submodule_free(sm);
                       }
               }
       }
       if (error == GIT_ITEROVER)
               error = 0;
       git_buf_free(&name);
       git_iterator_free(i);
       return error;
}
static int submodules_from_head(git_strmap *map, git_tree *head, git_config *cfg)
{
       int error;
       git_iterator *i;
       const git_index_entry *entry;
       git_buf name = GIT_BUF_INIT;
       if ((error = git_iterator_for_tree(&i, head, NULL)) < 0)
               return error;
       while (!(error = git_iterator_advance(&entry, i))) {
               khiter_t pos = git_strmap_lookup_index(map, entry->path);
               git_submodule *sm;
               git_buf_clear(&name);
               if (!name_from_path(&name, cfg, entry->path)) {
                       git_strmap_lookup_index(map, name.ptr);
               }
               if (git_strmap_valid_index(map, pos)) {
                       sm = git_strmap_value_at(map, pos);
                       if (S_ISGITLINK(entry->mode))
                               submodule_update_from_head_data(sm, entry->mode, &entry->id);
                       else
                               sm->flags |= GIT_SUBMODULE_STATUS__HEAD_NOT_SUBMODULE;
               } else if (S_ISGITLINK(entry->mode)) {
                       if (!submodule_get_or_create(&sm, git_tree_owner(head), map, name.ptr ? name.ptr : entry->path)) {
                               submodule_update_from_head_data(
                                       sm, entry->mode, &entry->id);
                               git_submodule_free(sm);
                       }
               }
       }
       if (error == GIT_ITEROVER)
               error = 0;
       git_buf_free(&name);
       git_iterator_free(i);
       return error;
}
/* If have_sm is true, sm is populated, otherwise map an repo are. */
typedef struct {
        git_config *mods;
        git_strmap *map;
        git_repository *repo;
} lfc_data;
static int all_submodules(git_repository *repo, git_strmap *map)
{
        int error = 0;
        git_index *idx = NULL;
        git_tree *head = NULL;
        const char *wd = NULL;
        git_buf path = GIT_BUF_INIT;
        git_submodule *sm;
        git_config *mods = NULL;
        uint32_t mask;
        assert(repo && map);
        /* get sources that we will need to check */
        if (git_repository_index(&idx, repo) < 0)
                giterr_clear();
        if (git_repository_head_tree(&head, repo) < 0)
                giterr_clear();
        wd = git_repository_workdir(repo);
        if (wd && (error = git_buf_joinpath(&path, wd, GIT_MODULES_FILE)) < 0)
                goto cleanup;
        /* clear submodule flags that are to be refreshed */
        mask = 0;
        mask |= GIT_SUBMODULE_STATUS_IN_INDEX |
                GIT_SUBMODULE_STATUS__INDEX_FLAGS |
                GIT_SUBMODULE_STATUS__INDEX_OID_VALID |
                GIT_SUBMODULE_STATUS__INDEX_MULTIPLE_ENTRIES;
        mask |= GIT_SUBMODULE_STATUS_IN_HEAD |
                GIT_SUBMODULE_STATUS__HEAD_OID_VALID;
        mask |= GIT_SUBMODULE_STATUS_IN_CONFIG;
        if (mask != 0)
                mask |= GIT_SUBMODULE_STATUS_IN_WD |
                        GIT_SUBMODULE_STATUS__WD_SCANNED |
                        GIT_SUBMODULE_STATUS__WD_FLAGS |
                        GIT_SUBMODULE_STATUS__WD_OID_VALID;
        /* add submodule information from .gitmodules */
        if (wd) {
                lfc_data data = { 0 };
                data.map = map;
                data.repo = repo;
                if ((mods = gitmodules_snapshot(repo)) == NULL)
                        goto cleanup;
                data.mods = mods;
                if ((error = git_config_foreach(
                            mods, submodule_load_each, &data)) < 0)
                        goto cleanup;
        }
        /* add back submodule information from index */
        if (idx) {
                if ((error = submodules_from_index(map, idx, mods)) < 0)
                        goto cleanup;
        }
        /* add submodule information from HEAD */
        if (head) {
                if ((error = submodules_from_head(map, head, mods)) < 0)
                        goto cleanup;
        }
        /* shallow scan submodules in work tree as needed */
        if (wd && mask != 0) {
                git_strmap_foreach_value(map, sm, {
                                submodule_load_from_wd_lite(sm);
                        });
        }
cleanup:
        git_config_free(mods);
        /* TODO: if we got an error, mark submodule config as invalid? */
        git_index_free(idx);
        git_tree_free(head);
        git_buf_free(&path);
        return error;
}
int git_submodule_foreach(
        git_repository *repo,
        int (*callback)(git_submodule *sm, const char *name, void *payload),
        void *payload)
{
        git_vector snapshot = GIT_VECTOR_INIT;
        git_strmap *submodules;
        git_submodule *sm;
        int error;
        size_t i;
        if ((error = git_strmap_alloc(&submodules)) < 0)
                return error;
        if ((error = all_submodules(repo, submodules)) < 0)
                goto done;
        if (!(error = git_vector_init(
                        &snapshot, kh_size(submodules), submodule_cmp))) {
                git_strmap_foreach_value(submodules, sm, {
                        if ((error = git_vector_insert(&snapshot, sm)) < 0)
                                break;
                        GIT_REFCOUNT_INC(sm);
                });
        }
        if (error < 0)
                goto done;
        git_vector_uniq(&snapshot, submodule_free_dup);
        git_vector_foreach(&snapshot, i, sm) {
                if ((error = callback(sm, sm->name, payload)) != 0) {
                        giterr_set_after_callback(error);
                        break;
                }
        }
done:
        git_vector_foreach(&snapshot, i, sm)
                git_submodule_free(sm);
        git_vector_free(&snapshot);
        git_strmap_foreach_value(submodules, sm, {
                git_submodule_free(sm);
        });
        git_strmap_free(submodules);
        return error;
}
static int submodule_repo_init(
        git_repository **out,
        git_repository *parent_repo,
        const char *path,
        const char *url,
        bool use_gitlink)
{
        int error = 0;
        git_buf workdir = GIT_BUF_INIT, repodir = GIT_BUF_INIT;
        git_repository_init_options initopt = GIT_REPOSITORY_INIT_OPTIONS_INIT;
        git_repository *subrepo = NULL;
        error = git_buf_joinpath(&workdir, git_repository_workdir(parent_repo), path);
        if (error < 0)
                goto cleanup;
        initopt.flags = GIT_REPOSITORY_INIT_MKPATH | GIT_REPOSITORY_INIT_NO_REINIT;
        initopt.origin_url = url;
        /* init submodule repository and add origin remote as needed */
        /* New style: sub-repo goes in <repo-dir>/modules/<name>/ with a
         * gitlink in the sub-repo workdir directory to that repository
         *
         * Old style: sub-repo goes directly into repo/<name>/.git/
         */
         if (use_gitlink) {
                error = git_buf_join3(
                        &repodir, '/', git_repository_path(parent_repo), "modules", path);
                if (error < 0)
                        goto cleanup;
                initopt.workdir_path = workdir.ptr;
                initopt.flags |=
                        GIT_REPOSITORY_INIT_NO_DOTGIT_DIR |
                        GIT_REPOSITORY_INIT_RELATIVE_GITLINK;
                error = git_repository_init_ext(&subrepo, repodir.ptr, &initopt);
        } else
                error = git_repository_init_ext(&subrepo, workdir.ptr, &initopt);
cleanup:
        git_buf_free(&workdir);
        git_buf_free(&repodir);
        *out = subrepo;
        return error;
}
int git_submodule_add_setup(
        git_submodule **out,
        git_repository *repo,
        const char *url,
        const char *path,
        int use_gitlink)
{
        int error = 0;
        git_config_backend *mods = NULL;
        git_submodule *sm = NULL;
        git_buf name = GIT_BUF_INIT, real_url = GIT_BUF_INIT;
        git_repository *subrepo = NULL;
        assert(repo && url && path);
        /* see if there is already an entry for this submodule */
        if (git_submodule_lookup(NULL, repo, path) < 0)
                giterr_clear();
        else {
                giterr_set(GITERR_SUBMODULE,
                        "Attempt to add submodule '%s' that already exists", path);
                return GIT_EEXISTS;
        }
        /* validate and normalize path */
        if (git__prefixcmp(path, git_repository_workdir(repo)) == 0)
                path += strlen(git_repository_workdir(repo));
        if (git_path_root(path) >= 0) {
                giterr_set(GITERR_SUBMODULE, "Submodule path must be a relative path");
                error = -1;
                goto cleanup;
        }
        /* update .gitmodules */
        if (!(mods = open_gitmodules(repo, GITMODULES_CREATE))) {
                giterr_set(GITERR_SUBMODULE,
                        "Adding submodules to a bare repository is not supported");
                return -1;
        }
        if ((error = git_buf_printf(&name, "submodule.%s.path", path)) < 0 ||
                (error = git_config_file_set_string(mods, name.ptr, path)) < 0)
                goto cleanup;
        if ((error = submodule_config_key_trunc_puts(&name, "url")) < 0 ||
                (error = git_config_file_set_string(mods, name.ptr, url)) < 0)
                goto cleanup;
        git_buf_clear(&name);
        /* init submodule repository and add origin remote as needed */
        error = git_buf_joinpath(&name, git_repository_workdir(repo), path);
        if (error < 0)
                goto cleanup;
        /* if the repo does not already exist, then init a new repo and add it.
         * Otherwise, just add the existing repo.
         */
        if (!(git_path_exists(name.ptr) &&
                git_path_contains(&name, DOT_GIT))) {
                /* resolve the actual URL to use */
                if ((error = git_submodule_resolve_url(&real_url, repo, url)) < 0)
                        goto cleanup;
                 if ((error = submodule_repo_init(&subrepo, repo, path, real_url.ptr, use_gitlink)) < 0)
                        goto cleanup;
        }
        if ((error = git_submodule_lookup(&sm, repo, path)) < 0)
                goto cleanup;
        error = git_submodule_init(sm, false);
cleanup:
        if (error && sm) {
                git_submodule_free(sm);
                sm = NULL;
        }
        if (out != NULL)
                *out = sm;
        git_config_file_free(mods);
        git_repository_free(subrepo);
        git_buf_free(&real_url);
        git_buf_free(&name);
        return error;
}
int git_submodule_repo_init(
        git_repository **out,
        const git_submodule *sm,
        int use_gitlink)
{
        int error;
        git_repository *sub_repo = NULL;
        const char *configured_url;
        git_config *cfg = NULL;
        git_buf buf = GIT_BUF_INIT;
        assert(out && sm);
        /* get the configured remote url of the submodule */
        if ((error = git_buf_printf(&buf, "submodule.%s.url", sm->name)) < 0 ||
                (error = git_repository_config_snapshot(&cfg, sm->repo)) < 0 ||
                (error = git_config_get_string(&configured_url, cfg, buf.ptr)) < 0 ||
                (error = submodule_repo_init(&sub_repo, sm->repo, sm->path, configured_url, use_gitlink)) < 0)
                goto done;
        *out = sub_repo;
done:
        git_config_free(cfg);
        git_buf_free(&buf);
        return error;
}
int git_submodule_add_finalize(git_submodule *sm)
{
        int error;
        git_index *index;
        assert(sm);
        if ((error = git_repository_index__weakptr(&index, sm->repo)) < 0 ||
                (error = git_index_add_bypath(index, GIT_MODULES_FILE)) < 0)
                return error;
        return git_submodule_add_to_index(sm, true);
}
int git_submodule_add_to_index(git_submodule *sm, int write_index)
{
        int error;
        git_repository *sm_repo = NULL;
        git_index *index;
        git_buf path = GIT_BUF_INIT;
        git_commit *head;
        git_index_entry entry;
        struct stat st;
        assert(sm);
        /* force reload of wd OID by git_submodule_open */
        sm->flags = sm->flags & ~GIT_SUBMODULE_STATUS__WD_OID_VALID;
        if ((error = git_repository_index__weakptr(&index, sm->repo)) < 0 ||
                (error = git_buf_joinpath(
                        &path, git_repository_workdir(sm->repo), sm->path)) < 0 ||
                (error = git_submodule_open(&sm_repo, sm)) < 0)
                goto cleanup;
        /* read stat information for submodule working directory */
        if (p_stat(path.ptr, &st) < 0) {
                giterr_set(GITERR_SUBMODULE,
                        "Cannot add submodule without working directory");
                error = -1;
                goto cleanup;
        }
        memset(&entry, 0, sizeof(entry));
        entry.path = sm->path;
        git_index_entry__init_from_stat(
                &entry, &st, !(git_index_caps(index) & GIT_INDEXCAP_NO_FILEMODE));
        /* calling git_submodule_open will have set sm->wd_oid if possible */
        if ((sm->flags & GIT_SUBMODULE_STATUS__WD_OID_VALID) == 0) {
                giterr_set(GITERR_SUBMODULE,
                        "Cannot add submodule without HEAD to index");
                error = -1;
                goto cleanup;
        }
        git_oid_cpy(&entry.id, &sm->wd_oid);
        if ((error = git_commit_lookup(&head, sm_repo, &sm->wd_oid)) < 0)
                goto cleanup;
        entry.ctime.seconds = git_commit_time(head);
        entry.ctime.nanoseconds = 0;
        entry.mtime.seconds = git_commit_time(head);
        entry.mtime.nanoseconds = 0;
        git_commit_free(head);
        /* add it */
        error = git_index_add(index, &entry);
        /* write it, if requested */
        if (!error && write_index) {
                error = git_index_write(index);
                if (!error)
                        git_oid_cpy(&sm->index_oid, &sm->wd_oid);
        }
cleanup:
        git_repository_free(sm_repo);
        git_buf_free(&path);
        return error;
}
const char *git_submodule_update_to_str(git_submodule_update_t update)
{
        int i;
        for (i = 0; i < (int)ARRAY_SIZE(_sm_update_map); ++i)
                if (_sm_update_map[i].map_value == (int)update)
                        return _sm_update_map[i].str_match;
        return NULL;
}
git_repository *git_submodule_owner(git_submodule *submodule)
{
        assert(submodule);
        return submodule->repo;
}
const char *git_submodule_name(git_submodule *submodule)
{
        assert(submodule);
        return submodule->name;
}
const char *git_submodule_path(git_submodule *submodule)
{
        assert(submodule);
        return submodule->path;
}
const char *git_submodule_url(git_submodule *submodule)
{
        assert(submodule);
        return submodule->url;
}
int git_submodule_resolve_url(git_buf *out, git_repository *repo, const char *url)
{
        int error = 0;
        git_buf normalized = GIT_BUF_INIT;
        assert(out && repo && url);
        git_buf_sanitize(out);
        /* We do this in all platforms in case someone on Windows created the .gitmodules */
        if (strchr(url, '\\')) {
                if ((error = git_path_normalize_slashes(&normalized, url)) < 0)
                        return error;
                url = normalized.ptr;
        }
        if (git_path_is_relative(url)) {
                if (!(error = get_url_base(out, repo)))
                        error = git_path_apply_relative(out, url);
        } else if (strchr(url, ':') != NULL || url[0] == '/') {
                error = git_buf_sets(out, url);
        } else {
                giterr_set(GITERR_SUBMODULE, "Invalid format for submodule URL");
                error = -1;
        }
        git_buf_free(&normalized);
        return error;
}
static int write_var(git_repository *repo, const char *name, const char *var, const char *val)
{
        git_buf key = GIT_BUF_INIT;
        git_config_backend *mods;
        int error;
        mods = open_gitmodules(repo, GITMODULES_CREATE);
        if (!mods)
                return -1;
        if ((error = git_buf_printf(&key, "submodule.%s.%s", name, var)) < 0)
                goto cleanup;
        if (val)
                error = git_config_file_set_string(mods, key.ptr, val);
        else
                error = git_config_file_delete(mods, key.ptr);
        git_buf_free(&key);
cleanup:
        git_config_file_free(mods);
        return error;
}
static int write_mapped_var(git_repository *repo, const char *name, git_cvar_map *maps, size_t nmaps, const char *var, int ival)
{
        git_cvar_t type;
        const char *val;
        if (git_config_lookup_map_enum(&type, &val, maps, nmaps, ival) < 0) {
                giterr_set(GITERR_SUBMODULE, "invalid value for %s", var);
                return -1;
        }
        if (type == GIT_CVAR_TRUE)
                val = "true";
        return write_var(repo, name, var, val);
}
const char *git_submodule_branch(git_submodule *submodule)
{
        assert(submodule);
        return submodule->branch;
}
int git_submodule_set_branch(git_repository *repo, const char *name, const char *branch)
{
        assert(repo && name);
        return write_var(repo, name, "branch", branch);
}
int git_submodule_set_url(git_repository *repo, const char *name, const char *url)
{
        assert(repo && name && url);
        return write_var(repo, name, "url", url);
}
const git_oid *git_submodule_index_id(git_submodule *submodule)
{
        assert(submodule);
        if (submodule->flags & GIT_SUBMODULE_STATUS__INDEX_OID_VALID)
                return &submodule->index_oid;
        else
                return NULL;
}
const git_oid *git_submodule_head_id(git_submodule *submodule)
{
        assert(submodule);
        if (submodule->flags & GIT_SUBMODULE_STATUS__HEAD_OID_VALID)
                return &submodule->head_oid;
        else
                return NULL;
}
const git_oid *git_submodule_wd_id(git_submodule *submodule)
{
        assert(submodule);
        /* load unless we think we have a valid oid */
        if (!(submodule->flags & GIT_SUBMODULE_STATUS__WD_OID_VALID)) {
                git_repository *subrepo;
                /* calling submodule open grabs the HEAD OID if possible */
                if (!git_submodule_open_bare(&subrepo, submodule))
                        git_repository_free(subrepo);
                else
                        giterr_clear();
        }
        if (submodule->flags & GIT_SUBMODULE_STATUS__WD_OID_VALID)
                return &submodule->wd_oid;
        else
                return NULL;
}
git_submodule_ignore_t git_submodule_ignore(git_submodule *submodule)
{
        assert(submodule);
        return (submodule->ignore < GIT_SUBMODULE_IGNORE_NONE) ?
                GIT_SUBMODULE_IGNORE_NONE : submodule->ignore;
}
int git_submodule_set_ignore(git_repository *repo, const char *name, git_submodule_ignore_t ignore)
{
        assert(repo && name);
        return write_mapped_var(repo, name, _sm_ignore_map, ARRAY_SIZE(_sm_ignore_map), "ignore", ignore);
}
git_submodule_update_t git_submodule_update_strategy(git_submodule *submodule)
{
        assert(submodule);
        return (submodule->update < GIT_SUBMODULE_UPDATE_CHECKOUT) ?
                GIT_SUBMODULE_UPDATE_CHECKOUT : submodule->update;
}
int git_submodule_set_update(git_repository *repo, const char *name, git_submodule_update_t update)
{
        assert(repo && name);
        return write_mapped_var(repo, name, _sm_update_map, ARRAY_SIZE(_sm_update_map), "update", update);
}
git_submodule_recurse_t git_submodule_fetch_recurse_submodules(
        git_submodule *submodule)
{
        assert(submodule);
        return submodule->fetch_recurse;
}
int git_submodule_set_fetch_recurse_submodules(git_repository *repo, const char *name, git_submodule_recurse_t recurse)
{
        assert(repo && name);
        return write_mapped_var(repo, name, _sm_recurse_map, ARRAY_SIZE(_sm_recurse_map), "fetchRecurseSubmodules", recurse);
}
static int submodule_repo_create(
        git_repository **out,
        git_repository *parent_repo,
        const char *path)
{
        int error = 0;
        git_buf workdir = GIT_BUF_INIT, repodir = GIT_BUF_INIT;
        git_repository_init_options initopt = GIT_REPOSITORY_INIT_OPTIONS_INIT;
        git_repository *subrepo = NULL;
        initopt.flags =
                GIT_REPOSITORY_INIT_MKPATH |
                GIT_REPOSITORY_INIT_NO_REINIT |
                GIT_REPOSITORY_INIT_NO_DOTGIT_DIR |
                GIT_REPOSITORY_INIT_RELATIVE_GITLINK;
        /* Workdir: path to sub-repo working directory */
        error = git_buf_joinpath(&workdir, git_repository_workdir(parent_repo), path);
        if (error < 0)
                goto cleanup;
        initopt.workdir_path = workdir.ptr;
        /**
         * Repodir: path to the sub-repo. sub-repo goes in:
         * <repo-dir>/modules/<name>/ with a gitlink in the 
         * sub-repo workdir directory to that repository.
         */
        error = git_buf_join3(
                &repodir, '/', git_repository_path(parent_repo), "modules", path);
        if (error < 0)
                goto cleanup;
        error = git_repository_init_ext(&subrepo, repodir.ptr, &initopt);
cleanup:
        git_buf_free(&workdir);
        git_buf_free(&repodir);
        *out = subrepo;
        return error;
}
/**
 * Callback to override sub-repository creation when
 * cloning a sub-repository.
 */
static int git_submodule_update_repo_init_cb(
        git_repository **out,
        const char *path,
        int bare,
        void *payload)
{
        git_submodule *sm;
        GIT_UNUSED(bare);
        sm = payload;
        return submodule_repo_create(out, sm->repo, path);
}
int git_submodule_update_init_options(git_submodule_update_options *opts, unsigned int version)
{
        GIT_INIT_STRUCTURE_FROM_TEMPLATE(
                opts, version, git_submodule_update_options, GIT_SUBMODULE_UPDATE_OPTIONS_INIT);
        return 0;
}
int git_submodule_update(git_submodule *sm, int init, git_submodule_update_options *_update_options)
{
        int error;
        unsigned int submodule_status;
        git_config *config = NULL;
        const char *submodule_url;
        git_repository *sub_repo = NULL;
        git_remote *remote = NULL;
        git_object *target_commit = NULL;
        git_buf buf = GIT_BUF_INIT;
        git_submodule_update_options update_options = GIT_SUBMODULE_UPDATE_OPTIONS_INIT;
        git_clone_options clone_options = GIT_CLONE_OPTIONS_INIT;
        assert(sm);
        if (_update_options)
                memcpy(&update_options, _update_options, sizeof(git_submodule_update_options));
        GITERR_CHECK_VERSION(&update_options, GIT_SUBMODULE_UPDATE_OPTIONS_VERSION, "git_submodule_update_options");
        /* Copy over the remote callbacks */
        memcpy(&clone_options.fetch_opts, &update_options.fetch_opts, sizeof(git_fetch_options));
        /* Get the status of the submodule to determine if it is already initialized  */
        if ((error = git_submodule_status(&submodule_status, sm->repo, sm->name, GIT_SUBMODULE_IGNORE_UNSPECIFIED)) < 0)
                goto done;
        /*
         * If submodule work dir is not already initialized, check to see
         * what we need to do (initialize, clone, return error...)
         */
        if (submodule_status & GIT_SUBMODULE_STATUS_WD_UNINITIALIZED) {
                /*
                 * Work dir is not initialized, check to see if the submodule
                 * info has been copied into .git/config
                 */
                if ((error = git_repository_config_snapshot(&config, sm->repo)) < 0 ||
                        (error = git_buf_printf(&buf, "submodule.%s.url", git_submodule_name(sm))) < 0)
                        goto done;
                if ((error = git_config_get_string(&submodule_url, config, git_buf_cstr(&buf))) < 0) {
                        /*
                         * If the error is not "not found" or if it is "not found" and we are not
                         * initializing the submodule, then return error.
                         */
                        if (error != GIT_ENOTFOUND)
                                goto done;
                        if (error == GIT_ENOTFOUND && !init) {
                                giterr_set(GITERR_SUBMODULE, "Submodule is not initialized.");
                                error = GIT_ERROR;
                                goto done;
                        }
                        /* The submodule has not been initialized yet - initialize it now.*/
                        if ((error = git_submodule_init(sm, 0)) < 0)
                                goto done;
                        git_config_free(config);
                        config = NULL;
                        if ((error = git_repository_config_snapshot(&config, sm->repo)) < 0 ||
                                (error = git_config_get_string(&submodule_url, config, git_buf_cstr(&buf))) < 0)
                                goto done;
                }
                /** submodule is initialized - now clone it **/
                /* override repo creation */
                clone_options.repository_cb = git_submodule_update_repo_init_cb;
                clone_options.repository_cb_payload = sm;
                /*
                 * Do not perform checkout as part of clone, instead we 
                 * will checkout the specific commit manually.
                 */
                clone_options.checkout_opts.checkout_strategy = GIT_CHECKOUT_NONE;
                update_options.checkout_opts.checkout_strategy = update_options.clone_checkout_strategy;
                if ((error = git_clone(&sub_repo, submodule_url, sm->path, &clone_options)) < 0 ||
                        (error = git_repository_set_head_detached(sub_repo, git_submodule_index_id(sm))) < 0 ||
                        (error = git_checkout_head(sub_repo, &update_options.checkout_opts)) != 0)
                        goto done;
        } else {
                /**
                 * Work dir is initialized - look up the commit in the parent repository's index,
                 * update the workdir contents of the subrepository, and set the subrepository's
                 * head to the new commit.
                 */
                if ((error = git_submodule_open(&sub_repo, sm)) < 0 ||
                        (error = git_object_lookup(&target_commit, sub_repo, git_submodule_index_id(sm), GIT_OBJ_COMMIT)) < 0 ||
                        (error = git_checkout_tree(sub_repo, target_commit, &update_options.checkout_opts)) != 0 ||
                        (error = git_repository_set_head_detached(sub_repo, git_submodule_index_id(sm))) < 0)
                        goto done;
                /* Invalidate the wd flags as the workdir has been updated. */
                sm->flags = sm->flags &
                        ~(GIT_SUBMODULE_STATUS_IN_WD |
                        GIT_SUBMODULE_STATUS__WD_OID_VALID |
                        GIT_SUBMODULE_STATUS__WD_SCANNED);
        }
done:
        git_buf_free(&buf);
        git_config_free(config);
        git_object_free(target_commit);
        git_remote_free(remote);
        git_repository_free(sub_repo);
        return error;
}
int git_submodule_init(git_submodule *sm, int overwrite)
{
        int error;
        const char *val;
        git_buf key = GIT_BUF_INIT, effective_submodule_url = GIT_BUF_INIT;
        git_config *cfg = NULL;
        if (!sm->url) {
                giterr_set(GITERR_SUBMODULE,
                        "No URL configured for submodule '%s'", sm->name);
                return -1;
        }
        if ((error = git_repository_config(&cfg, sm->repo)) < 0)
                return error;
        /* write "submodule.NAME.url" */
        if ((error = git_submodule_resolve_url(&effective_submodule_url, sm->repo, sm->url)) < 0 ||
                (error = git_buf_printf(&key, "submodule.%s.url", sm->name)) < 0 ||
                (error = git_config__update_entry(
                        cfg, key.ptr, effective_submodule_url.ptr, overwrite != 0, false)) < 0)
                goto cleanup;
        /* write "submodule.NAME.update" if not default */
        val = (sm->update == GIT_SUBMODULE_UPDATE_CHECKOUT) ?
                NULL : git_submodule_update_to_str(sm->update);
        if ((error = git_buf_printf(&key, "submodule.%s.update", sm->name)) < 0 ||
                (error = git_config__update_entry(
                        cfg, key.ptr, val, overwrite != 0, false)) < 0)
                goto cleanup;
        /* success */
cleanup:
        git_config_free(cfg);
        git_buf_free(&key);
        git_buf_free(&effective_submodule_url);
        return error;
}
int git_submodule_sync(git_submodule *sm)
{
        int error = 0;
        git_config *cfg = NULL;
        git_buf key = GIT_BUF_INIT;
        git_repository *smrepo = NULL;
        if (!sm->url) {
                giterr_set(GITERR_SUBMODULE,
                        "No URL configured for submodule '%s'", sm->name);
                return -1;
        }
        /* copy URL over to config only if it already exists */
        if (!(error = git_repository_config__weakptr(&cfg, sm->repo)) &&
                !(error = git_buf_printf(&key, "submodule.%s.url", sm->name)))
                error = git_config__update_entry(cfg, key.ptr, sm->url, true, true);
        /* if submodule exists in the working directory, update remote url */
        if (!error &&
                (sm->flags & GIT_SUBMODULE_STATUS_IN_WD) != 0 &&
                !(error = git_submodule_open(&smrepo, sm)))
        {
                git_buf remote_name = GIT_BUF_INIT;
                if ((error = git_repository_config__weakptr(&cfg, smrepo)) < 0)
                        /* return error from reading submodule config */;
                else if ((error = lookup_head_remote_key(&remote_name, smrepo)) < 0) {
                        giterr_clear();
                        error = git_buf_sets(&key, "remote.origin.url");
                } else {
                        error = git_buf_join3(
                                &key, '.', "remote", remote_name.ptr, "url");
                        git_buf_free(&remote_name);
                }
                if (!error)
                        error = git_config__update_entry(cfg, key.ptr, sm->url, true, false);
                git_repository_free(smrepo);
        }
        git_buf_free(&key);
        return error;
}
static int git_submodule__open(
        git_repository **subrepo, git_submodule *sm, bool bare)
{
        int error;
        git_buf path = GIT_BUF_INIT;
        unsigned int flags = GIT_REPOSITORY_OPEN_NO_SEARCH;
        const char *wd;
        assert(sm && subrepo);
        if (git_repository__ensure_not_bare(
                        sm->repo, "open submodule repository") < 0)
                return GIT_EBAREREPO;
        wd = git_repository_workdir(sm->repo);
        if (git_buf_joinpath(&path, wd, sm->path) < 0 ||
                git_buf_joinpath(&path, path.ptr, DOT_GIT) < 0)
                return -1;
        sm->flags = sm->flags &
                ~(GIT_SUBMODULE_STATUS_IN_WD |
                  GIT_SUBMODULE_STATUS__WD_OID_VALID |
                  GIT_SUBMODULE_STATUS__WD_SCANNED);
        if (bare)
                flags |= GIT_REPOSITORY_OPEN_BARE;
        error = git_repository_open_ext(subrepo, path.ptr, flags, wd);
        /* if we opened the submodule successfully, grab HEAD OID, etc. */
        if (!error) {
                sm->flags |= GIT_SUBMODULE_STATUS_IN_WD |
                        GIT_SUBMODULE_STATUS__WD_SCANNED;
                if (!git_reference_name_to_id(&sm->wd_oid, *subrepo, GIT_HEAD_FILE))
                        sm->flags |= GIT_SUBMODULE_STATUS__WD_OID_VALID;
                else
                        giterr_clear();
        } else if (git_path_exists(path.ptr)) {
                sm->flags |= GIT_SUBMODULE_STATUS__WD_SCANNED |
                        GIT_SUBMODULE_STATUS_IN_WD;
        } else {
                git_buf_rtruncate_at_char(&path, '/'); /* remove "/.git" */
                if (git_path_isdir(path.ptr))
                        sm->flags |= GIT_SUBMODULE_STATUS__WD_SCANNED;
        }
        git_buf_free(&path);
        return error;
}
int git_submodule_open_bare(git_repository **subrepo, git_submodule *sm)
{
        return git_submodule__open(subrepo, sm, true);
}
int git_submodule_open(git_repository **subrepo, git_submodule *sm)
{
        return git_submodule__open(subrepo, sm, false);
}
static void submodule_update_from_index_entry(
        git_submodule *sm, const git_index_entry *ie)
{
        bool already_found = (sm->flags & GIT_SUBMODULE_STATUS_IN_INDEX) != 0;
        if (!S_ISGITLINK(ie->mode)) {
                if (!already_found)
                        sm->flags |= GIT_SUBMODULE_STATUS__INDEX_NOT_SUBMODULE;
        } else {
                if (already_found)
                        sm->flags |= GIT_SUBMODULE_STATUS__INDEX_MULTIPLE_ENTRIES;
                else
                        git_oid_cpy(&sm->index_oid, &ie->id);
                sm->flags |= GIT_SUBMODULE_STATUS_IN_INDEX |
                        GIT_SUBMODULE_STATUS__INDEX_OID_VALID;
        }
}
static int submodule_update_index(git_submodule *sm)
{
        git_index *index;
        const git_index_entry *ie;
        if (git_repository_index__weakptr(&index, sm->repo) < 0)
                return -1;
        sm->flags = sm->flags &
                ~(GIT_SUBMODULE_STATUS_IN_INDEX |
                  GIT_SUBMODULE_STATUS__INDEX_OID_VALID);
        if (!(ie = git_index_get_bypath(index, sm->path, 0)))
                return 0;
        submodule_update_from_index_entry(sm, ie);
        return 0;
}
static void submodule_update_from_head_data(
        git_submodule *sm, mode_t mode, const git_oid *id)
{
        if (!S_ISGITLINK(mode))
                sm->flags |= GIT_SUBMODULE_STATUS__HEAD_NOT_SUBMODULE;
        else {
                git_oid_cpy(&sm->head_oid, id);
                sm->flags |= GIT_SUBMODULE_STATUS_IN_HEAD |
                        GIT_SUBMODULE_STATUS__HEAD_OID_VALID;
        }
}
static int submodule_update_head(git_submodule *submodule)
{
        git_tree *head = NULL;
        git_tree_entry *te = NULL;
        submodule->flags = submodule->flags &
                ~(GIT_SUBMODULE_STATUS_IN_HEAD |
                  GIT_SUBMODULE_STATUS__HEAD_OID_VALID);
        /* if we can't look up file in current head, then done */
        if (git_repository_head_tree(&head, submodule->repo) < 0 ||
                git_tree_entry_bypath(&te, head, submodule->path) < 0)
                giterr_clear();
        else
                submodule_update_from_head_data(submodule, te->attr, &te->oid);
        git_tree_entry_free(te);
        git_tree_free(head);
        return 0;
}
int git_submodule_reload(git_submodule *sm, int force)
{
        int error = 0;
        git_config *mods;
        GIT_UNUSED(force);
        assert(sm);
        if (!git_repository_is_bare(sm->repo)) {
                /* refresh config data */
                mods = gitmodules_snapshot(sm->repo);
                if (mods != NULL) {
                        error = submodule_read_config(sm, mods);
                        git_config_free(mods);
                        if (error < 0)
                                return error;
                }
                /* refresh wd data */
                sm->flags &=
                        ~(GIT_SUBMODULE_STATUS_IN_WD |
                          GIT_SUBMODULE_STATUS__WD_OID_VALID |
                          GIT_SUBMODULE_STATUS__WD_FLAGS);
                error = submodule_load_from_wd_lite(sm);
        }
        if (error == 0 && (error = submodule_update_index(sm)) == 0)
                error = submodule_update_head(sm);
        return error;
}
static void submodule_copy_oid_maybe(
        git_oid *tgt, const git_oid *src, bool valid)
{
        if (tgt) {
                if (valid)
                        memcpy(tgt, src, sizeof(*tgt));
                else
                        memset(tgt, 0, sizeof(*tgt));
        }
}
int git_submodule__status(
        unsigned int *out_status,
        git_oid *out_head_id,
        git_oid *out_index_id,
        git_oid *out_wd_id,
        git_submodule *sm,
        git_submodule_ignore_t ign)
{
        unsigned int status;
        git_repository *smrepo = NULL;
        if (ign == GIT_SUBMODULE_IGNORE_UNSPECIFIED)
                ign = sm->ignore;
        /* only return location info if ignore == all */
        if (ign == GIT_SUBMODULE_IGNORE_ALL) {
                *out_status = (sm->flags & GIT_SUBMODULE_STATUS__IN_FLAGS);
                return 0;
        }
        /* refresh the index OID */
        if (submodule_update_index(sm) < 0)
                return -1;
        /* refresh the HEAD OID */
        if (submodule_update_head(sm) < 0)
                return -1;
        /* for ignore == dirty, don't scan the working directory */
        if (ign == GIT_SUBMODULE_IGNORE_DIRTY) {
                /* git_submodule_open_bare will load WD OID data */
                if (git_submodule_open_bare(&smrepo, sm) < 0)
                        giterr_clear();
                else
                        git_repository_free(smrepo);
                smrepo = NULL;
        } else if (git_submodule_open(&smrepo, sm) < 0) {
                giterr_clear();
                smrepo = NULL;
        }
        status = GIT_SUBMODULE_STATUS__CLEAR_INTERNAL(sm->flags);
        submodule_get_index_status(&status, sm);
        submodule_get_wd_status(&status, sm, smrepo, ign);
        git_repository_free(smrepo);
        *out_status = status;
        submodule_copy_oid_maybe(out_head_id, &sm->head_oid,
                (sm->flags & GIT_SUBMODULE_STATUS__HEAD_OID_VALID) != 0);
        submodule_copy_oid_maybe(out_index_id, &sm->index_oid,
                (sm->flags & GIT_SUBMODULE_STATUS__INDEX_OID_VALID) != 0);
        submodule_copy_oid_maybe(out_wd_id, &sm->wd_oid,
                (sm->flags & GIT_SUBMODULE_STATUS__WD_OID_VALID) != 0);
        return 0;
}
int git_submodule_status(unsigned int *status, git_repository *repo, const char *name, git_submodule_ignore_t ignore)
{
        git_submodule *sm;
        int error;
        assert(status && repo && name);
        if ((error = git_submodule_lookup(&sm, repo, name)) < 0)
                return error;
        error = git_submodule__status(status, NULL, NULL, NULL, sm, ignore);
        git_submodule_free(sm);
        return error;
}
int git_submodule_location(unsigned int *location, git_submodule *sm)
{
        assert(location && sm);
        return git_submodule__status(
                location, NULL, NULL, NULL, sm, GIT_SUBMODULE_IGNORE_ALL);
}
/*
 * INTERNAL FUNCTIONS
 */
static int submodule_alloc(
        git_submodule **out, git_repository *repo, const char *name)
{
        size_t namelen;
        git_submodule *sm;
        if (!name || !(namelen = strlen(name))) {
                giterr_set(GITERR_SUBMODULE, "Invalid submodule name");
                return -1;
        }
        sm = git__calloc(1, sizeof(git_submodule));
        GITERR_CHECK_ALLOC(sm);
        sm->name = sm->path = git__strdup(name);
        if (!sm->name) {
                git__free(sm);
                return -1;
        }
        GIT_REFCOUNT_INC(sm);
        sm->ignore = sm->ignore_default = GIT_SUBMODULE_IGNORE_NONE;
        sm->update = sm->update_default = GIT_SUBMODULE_UPDATE_CHECKOUT;
        sm->fetch_recurse = sm->fetch_recurse_default = GIT_SUBMODULE_RECURSE_NO;
        sm->repo   = repo;
        sm->branch = NULL;
        *out = sm;
        return 0;
}
static void submodule_release(git_submodule *sm)
{
        if (!sm)
                return;
        if (sm->repo) {
                sm->repo = NULL;
        }
        if (sm->path != sm->name)
                git__free(sm->path);
        git__free(sm->name);
        git__free(sm->url);
        git__free(sm->branch);
        git__memzero(sm, sizeof(*sm));
        git__free(sm);
}
void git_submodule_free(git_submodule *sm)
{
        if (!sm)
                return;
        GIT_REFCOUNT_DEC(sm, submodule_release);
}
static int submodule_config_error(const char *property, const char *value)
{
        giterr_set(GITERR_INVALID,
                "Invalid value for submodule '%s' property: '%s'", property, value);
        return -1;
}
int git_submodule_parse_ignore(git_submodule_ignore_t *out, const char *value)
{
        int val;
        if (git_config_lookup_map_value(
                        &val, _sm_ignore_map, ARRAY_SIZE(_sm_ignore_map), value) < 0) {
                *out = GIT_SUBMODULE_IGNORE_NONE;
                return submodule_config_error("ignore", value);
        }
        *out = (git_submodule_ignore_t)val;
        return 0;
}
int git_submodule_parse_update(git_submodule_update_t *out, const char *value)
{
        int val;
        if (git_config_lookup_map_value(
                        &val, _sm_update_map, ARRAY_SIZE(_sm_update_map), value) < 0) {
                *out = GIT_SUBMODULE_UPDATE_CHECKOUT;
                return submodule_config_error("update", value);
        }
        *out = (git_submodule_update_t)val;
        return 0;
}
int git_submodule_parse_recurse(git_submodule_recurse_t *out, const char *value)
{
        int val;
        if (git_config_lookup_map_value(
                        &val, _sm_recurse_map, ARRAY_SIZE(_sm_recurse_map), value) < 0) {
                *out = GIT_SUBMODULE_RECURSE_YES;
                return submodule_config_error("recurse", value);
        }
        *out = (git_submodule_recurse_t)val;
        return 0;
}
static int get_value(const char **out, git_config *cfg, git_buf *buf, const char *name, const char *field)
{
        int error;
        git_buf_clear(buf);
        if ((error = git_buf_printf(buf, "submodule.%s.%s", name, field)) < 0 ||
            (error = git_config_get_string(out, cfg, buf->ptr)) < 0)
                return error;
        return error;
}
static int submodule_read_config(git_submodule *sm, git_config *cfg)
{
        git_buf key = GIT_BUF_INIT;
        const char *value;
        int error, in_config = 0;
        /*
         * TODO: Look up path in index and if it is present but not a GITLINK
         * then this should be deleted (at least to match git's behavior)
         */
        if ((error = get_value(&value, cfg, &key, sm->name, "path")) == 0) {
                in_config = 1;
        /*
         * TODO: if case insensitive filesystem, then the following strcmp
         * should be strcasecmp
         */
                if (strcmp(sm->name, value) != 0) {
                        if (sm->path != sm->name)
                                git__free(sm->path);
                        sm->path = git__strdup(value);
                        GITERR_CHECK_ALLOC(sm->path);
                }
        } else if (error != GIT_ENOTFOUND) {
                goto cleanup;
        }
        if ((error = get_value(&value, cfg, &key, sm->name, "url")) == 0) {
                in_config = 1;
                sm->url = git__strdup(value);
                GITERR_CHECK_ALLOC(sm->url);
        } else if (error != GIT_ENOTFOUND) {
                goto cleanup;
        }
        if ((error = get_value(&value, cfg, &key, sm->name, "branch")) == 0) {
                in_config = 1;
                sm->branch = git__strdup(value);
                GITERR_CHECK_ALLOC(sm->branch);
        } else if (error != GIT_ENOTFOUND) {
                goto cleanup;
        }
        if ((error = get_value(&value, cfg, &key, sm->name, "update")) == 0) {
                in_config = 1;
                if ((error = git_submodule_parse_update(&sm->update, value)) < 0)
                        goto cleanup;
                sm->update_default = sm->update;
        } else if (error != GIT_ENOTFOUND) {
                goto cleanup;
        }
        if ((error = get_value(&value, cfg, &key, sm->name, "fetchRecurseSubmodules")) == 0) {
                in_config = 1;
                if ((error = git_submodule_parse_recurse(&sm->fetch_recurse, value)) < 0)
                        goto cleanup;
                sm->fetch_recurse_default = sm->fetch_recurse;
        } else if (error != GIT_ENOTFOUND) {
                goto cleanup;
        }
        if ((error = get_value(&value, cfg, &key, sm->name, "ignore")) == 0) {
                in_config = 1;
                if ((error = git_submodule_parse_ignore(&sm->ignore, value)) < 0)
                        goto cleanup;
                sm->ignore_default = sm->ignore;
        } else if (error != GIT_ENOTFOUND) {
                goto cleanup;
        }
        if (in_config)
                sm->flags |= GIT_SUBMODULE_STATUS_IN_CONFIG;
        error = 0;
cleanup:
        git_buf_free(&key);
        return error;
}
static int submodule_load_each(const git_config_entry *entry, void *payload)
{
        lfc_data *data = payload;
        const char *namestart, *property;
        git_strmap_iter pos;
        git_strmap *map = data->map;
        git_buf name = GIT_BUF_INIT;
        git_submodule *sm;
        int error;
        if (git__prefixcmp(entry->name, "submodule.") != 0)
                return 0;
        namestart = entry->name + strlen("submodule.");
        property  = strrchr(namestart, '.');
        if (!property || (property == namestart))
                return 0;
        property++;
        if ((error = git_buf_set(&name, namestart, property - namestart -1)) < 0)
                return error;
        /*
         * Now that we have the submodule's name, we can use that to
         * figure out whether it's in the map. If it's not, we create
         * a new submodule, load the config and insert it. If it's
         * already inserted, we've already loaded it, so we skip.
         */
        pos = git_strmap_lookup_index(map, name.ptr);
        if (git_strmap_valid_index(map, pos)) {
                error = 0;
                goto done;
        }
        if ((error = submodule_alloc(&sm, data->repo, name.ptr)) < 0)
                goto done;
        if ((error = submodule_read_config(sm, data->mods)) < 0) {
                git_submodule_free(sm);
                goto done;
        }
        git_strmap_insert(map, sm->name, sm, error);
        assert(error != 0);
        if (error < 0)
                goto done;
        error = 0;
done:
        git_buf_free(&name);
        return error;
}
static int submodule_load_from_wd_lite(git_submodule *sm)
{
        git_buf path = GIT_BUF_INIT;
        if (git_buf_joinpath(&path, git_repository_workdir(sm->repo), sm->path) < 0)
                return -1;
        if (git_path_isdir(path.ptr))
                sm->flags |= GIT_SUBMODULE_STATUS__WD_SCANNED;
        if (git_path_contains(&path, DOT_GIT))
                sm->flags |= GIT_SUBMODULE_STATUS_IN_WD;
        git_buf_free(&path);
        return 0;
}
/**
 * Returns a snapshot of $WORK_TREE/.gitmodules.
 *
 * We ignore any errors and just pretend the file isn't there.
 */
static git_config *gitmodules_snapshot(git_repository *repo)
{
        const char *workdir = git_repository_workdir(repo);
        git_config *mods = NULL, *snap = NULL;
        git_buf path = GIT_BUF_INIT;
        if (workdir != NULL) {
                if (git_buf_joinpath(&path, workdir, GIT_MODULES_FILE) != 0)
                        return NULL;
                if (git_config_open_ondisk(&mods, path.ptr) < 0)
                        mods = NULL;
        }
        git_buf_free(&path);
        if (mods) {
                git_config_snapshot(&snap, mods);
                git_config_free(mods);
        }
        return snap;
}
static git_config_backend *open_gitmodules(
        git_repository *repo,
        int okay_to_create)
{
        const char *workdir = git_repository_workdir(repo);
        git_buf path = GIT_BUF_INIT;
        git_config_backend *mods = NULL;
        if (workdir != NULL) {
                if (git_buf_joinpath(&path, workdir, GIT_MODULES_FILE) != 0)
                        return NULL;
                if (okay_to_create || git_path_isfile(path.ptr)) {
                        /* git_config_file__ondisk should only fail if OOM */
                        if (git_config_file__ondisk(&mods, path.ptr) < 0)
                                mods = NULL;
                        /* open should only fail here if the file is malformed */
                        else if (git_config_file_open(mods, GIT_CONFIG_LEVEL_LOCAL) < 0) {
                                git_config_file_free(mods);
                                mods = NULL;
                        }
                }
        }
        git_buf_free(&path);
        return mods;
}
/* Lookup name of remote of the local tracking branch HEAD points to */
static int lookup_head_remote_key(git_buf *remote_name, git_repository *repo)
{
        int error;
        git_reference *head = NULL;
        git_buf upstream_name = GIT_BUF_INIT;
        /* lookup and dereference HEAD */
        if ((error = git_repository_head(&head, repo)) < 0)
                return error;
        /**
         * If head does not refer to a branch, then return
         * GIT_ENOTFOUND to indicate that we could not find
         * a remote key for the local tracking branch HEAD points to.
         **/
        if (!git_reference_is_branch(head)) {
                giterr_set(GITERR_INVALID,
                        "HEAD does not refer to a branch.");
                error = GIT_ENOTFOUND;
                goto done;
        }
        /* lookup remote tracking branch of HEAD */
        if ((error = git_branch_upstream_name(
                &upstream_name,
                repo,
                git_reference_name(head))) < 0)
                goto done;
        /* lookup remote of remote tracking branch */
        if ((error = git_branch_remote_name(remote_name, repo, upstream_name.ptr)) < 0)
                goto done;
done:
        git_buf_free(&upstream_name);
        git_reference_free(head);
        return error;
}
/* Lookup the remote of the local tracking branch HEAD points to */
static int lookup_head_remote(git_remote **remote, git_repository *repo)
{
        int error;
        git_buf remote_name = GIT_BUF_INIT;
        /* lookup remote of remote tracking branch name */
        if (!(error = lookup_head_remote_key(&remote_name, repo)))
                error = git_remote_lookup(remote, repo, remote_name.ptr);
        git_buf_free(&remote_name);
        return error;
}
/* Lookup remote, either from HEAD or fall back on origin */
static int lookup_default_remote(git_remote **remote, git_repository *repo)
{
        int error = lookup_head_remote(remote, repo);
        /* if that failed, use 'origin' instead */
        if (error == GIT_ENOTFOUND)
                error = git_remote_lookup(remote, repo, "origin");
        if (error == GIT_ENOTFOUND)
                giterr_set(
                        GITERR_SUBMODULE,
                        "Cannot get default remote for submodule - no local tracking "
                        "branch for HEAD and origin does not exist");
        return error;
}
static int get_url_base(git_buf *url, git_repository *repo)
{
        int error;
        git_remote *remote = NULL;
        if (!(error = lookup_default_remote(&remote, repo))) {
                error = git_buf_sets(url, git_remote_url(remote));
                git_remote_free(remote);
        }
        else if (error == GIT_ENOTFOUND) {
                /* if repository does not have a default remote, use workdir instead */
                giterr_clear();
                error = git_buf_sets(url, git_repository_workdir(repo));
        }
        return error;
}
static void submodule_get_index_status(unsigned int *status, git_submodule *sm)
{
        const git_oid *head_oid  = git_submodule_head_id(sm);
        const git_oid *index_oid = git_submodule_index_id(sm);
        *status = *status & ~GIT_SUBMODULE_STATUS__INDEX_FLAGS;
        if (!head_oid) {
                if (index_oid)
                        *status |= GIT_SUBMODULE_STATUS_INDEX_ADDED;
        }
        else if (!index_oid)
                *status |= GIT_SUBMODULE_STATUS_INDEX_DELETED;
        else if (!git_oid_equal(head_oid, index_oid))
                *status |= GIT_SUBMODULE_STATUS_INDEX_MODIFIED;
}
static void submodule_get_wd_status(
        unsigned int *status,
        git_submodule *sm,
        git_repository *sm_repo,
        git_submodule_ignore_t ign)
{
        const git_oid *index_oid = git_submodule_index_id(sm);
        const git_oid *wd_oid =
                (sm->flags & GIT_SUBMODULE_STATUS__WD_OID_VALID) ? &sm->wd_oid : NULL;
        git_tree *sm_head = NULL;
        git_index *index = NULL;
        git_diff_options opt = GIT_DIFF_OPTIONS_INIT;
        git_diff *diff;
        *status = *status & ~GIT_SUBMODULE_STATUS__WD_FLAGS;
        if (!index_oid) {
                if (wd_oid)
                        *status |= GIT_SUBMODULE_STATUS_WD_ADDED;
        }
        else if (!wd_oid) {
                if ((sm->flags & GIT_SUBMODULE_STATUS__WD_SCANNED) != 0 &&
                        (sm->flags & GIT_SUBMODULE_STATUS_IN_WD) == 0)
                        *status |= GIT_SUBMODULE_STATUS_WD_UNINITIALIZED;
                else
                        *status |= GIT_SUBMODULE_STATUS_WD_DELETED;
        }
        else if (!git_oid_equal(index_oid, wd_oid))
                *status |= GIT_SUBMODULE_STATUS_WD_MODIFIED;
        /* if we have no repo, then we're done */
        if (!sm_repo)
                return;
        /* the diffs below could be optimized with an early termination
         * option to the git_diff functions, but for now this is sufficient
         * (and certainly no worse that what core git does).
         */
        if (ign == GIT_SUBMODULE_IGNORE_NONE)
                opt.flags |= GIT_DIFF_INCLUDE_UNTRACKED;
        (void)git_repository_index__weakptr(&index, sm_repo);
        /* if we don't have an unborn head, check diff with index */
        if (git_repository_head_tree(&sm_head, sm_repo) < 0)
                giterr_clear();
        else {
                /* perform head to index diff on submodule */
                if (git_diff_tree_to_index(&diff, sm_repo, sm_head, index, &opt) < 0)
                        giterr_clear();
                else {
                        if (git_diff_num_deltas(diff) > 0)
                                *status |= GIT_SUBMODULE_STATUS_WD_INDEX_MODIFIED;
                        git_diff_free(diff);
                        diff = NULL;
                }
                git_tree_free(sm_head);
        }
        /* perform index-to-workdir diff on submodule */
        if (git_diff_index_to_workdir(&diff, sm_repo, index, &opt) < 0)
                giterr_clear();
        else {
                size_t untracked =
                        git_diff_num_deltas_of_type(diff, GIT_DELTA_UNTRACKED);
                if (untracked > 0)
                        *status |= GIT_SUBMODULE_STATUS_WD_UNTRACKED;
                if (git_diff_num_deltas(diff) != untracked)
                        *status |= GIT_SUBMODULE_STATUS_WD_WD_MODIFIED;
                git_diff_free(diff);
                diff = NULL;
        }
}