git/repository.c
brian m. carlson 9412759925 repository: require a build flag to use SHA-256
At this point, SHA-256 support is experimental and some behavior may
change. To avoid surprising unsuspecting users, require a build flag,
ENABLE_SHA256, to allow use of a non-SHA-1 algorithm. Enable this flag
by default when the DEVELOPER make flag is set so that contributors can
test this case adequately.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:33:21 -08:00

282 lines
6.7 KiB
C

/*
* 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];
#ifndef ENABLE_SHA256
if (hash_algo != GIT_HASH_SHA1)
die(_("The hash algorithm %s is not supported in this build."), repo->hash_algo->name);
#endif
}
/*
* 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);
}