1 files changed, 277 insertions, 0 deletions
diff --git a/third_party/git/repository.c b/third_party/git/repository.c
new file mode 100644
index 000000000000..a4174ddb0629
--- /dev/null
+++ b/third_party/git/repository.c
@@ -0,0 +1,277 @@
+/*
+ * not really _using_ the compat macros, just make sure the_index
+ * declaration matches the definition in this file.
+ */
+#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#include "cache.h"
+#include "repository.h"
+#include "object-store.h"
+#include "config.h"
+#include "object.h"
+#include "lockfile.h"
+#include "submodule-config.h"
+
+/* The main repository */
+static struct repository the_repo;
+struct repository *the_repository;
+struct index_state the_index;
+
+void initialize_the_repository(void)
+{
+	the_repository = &the_repo;
+
+	the_repo.index = &the_index;
+	the_repo.objects = raw_object_store_new();
+	the_repo.parsed_objects = parsed_object_pool_new();
+
+	repo_set_hash_algo(&the_repo, GIT_HASH_SHA1);
+}
+
+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) {
+		repo->objects->odb = xcalloc(1, sizeof(*repo->objects->odb));
+		repo->objects->odb_tail = &repo->objects->odb->next;
+	}
+	expand_base_dir(&repo->objects->odb->path, o->object_dir,
+			repo->commondir, "objects");
+
+	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];
+}
+
+/*
+ * 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));
+
+	repo->objects = raw_object_store_new();
+	repo->parsed_objects = parsed_object_pool_new();
+
+	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);
+
+	if (worktree)
+		repo_set_worktree(repo, worktree);
+
+	clear_repository_format(&format);
+	return 0;
+
+error:
+	repo_clear(repo);
+	return -1;
+}
+
+int repo_submodule_init(struct repository *subrepo,
+			struct repository *superproject,
+			const struct submodule *sub)
+{
+	struct strbuf gitdir = STRBUF_INIT;
+	struct strbuf worktree = STRBUF_INIT;
+	int ret = 0;
+
+	if (!sub) {
+		ret = -1;
+		goto out;
+	}
+
+	strbuf_repo_worktree_path(&gitdir, superproject, "%s/.git", sub->path);
+	strbuf_repo_worktree_path(&worktree, superproject, "%s", sub->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.
+		 */
+		strbuf_reset(&gitdir);
+		strbuf_repo_git_path(&gitdir, superproject,
+				     "modules/%s", 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 :
+					    "", sub->path);
+
+out:
+	strbuf_release(&gitdir);
+	strbuf_release(&worktree);
+	return ret;
+}
+
+void repo_clear(struct repository *repo)
+{
+	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);
+
+	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);
+		if (repo->index != &the_index)
+			FREE_AND_NULL(repo->index);
+	}
+}
+
+int repo_read_index(struct repository *repo)
+{
+	if (!repo->index)
+		repo->index = xcalloc(1, sizeof(*repo->index));
+
+	return read_index_from(repo->index, repo->index_file, repo->gitdir);
+}
+
+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);
+}