Files
git/setup.h
brian m. carlson d6e616cee7 setup: use the default algorithm to initialize repo format
When we define a new repository format with REPOSITORY_FORMAT_INIT, we
always use GIT_HASH_SHA1, and this value ends up getting used as the
default value to initialize a repository if none of the command line,
environment, or config tell us to do otherwise.

Because we might not always want to use SHA-1 as the default, let's
instead specify the default hash algorithm constant so that we will use
whatever the specified default is.

However, we also need to continue to read older repositories.  If we're
in a v0 repository or extensions.objectformat is not set, then we must
continue to default to the original hash algorithm: SHA-1.  If an
algorithm is set explicitly, however, it will override the hash_algo
member of the repository_format struct and we'll get the right value.

Similarly, if the repository was initialized before Git 0.99.3, then it
may lack a core.repositoryformatversion key, and some repositories lack
a config file altogether.  In both cases, format->version is -1 and we
need to assume that SHA-1 is in use.

Because clear_repository_format reinitializes the struct
repository_format and therefore sets the hash_algo member to the default
(which could in the future not be SHA-1), we need to reset this member
explicitly.  We know, however, that at the point we call
read_repository_format, we are actually reading an existing repository
and not initializing a new one or operating outside of a repository, so
we are not changing the default behavior back to SHA-1 if the default
algorithm is different.

It is potentially questionable that we ignore all repository
configuration if there is a config file but it doesn't have
core.repositoryformatversion set, in which case we reset all of the
configuration to the default.  However, it is unclear what the right
thing to do instead with such an old repository is and a simple git init
will add the missing entry, so for now, we simply honor what the
existing code does and reset the value to the default, simply adding our
initialization to SHA-1.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-07-01 14:58:24 -07:00

235 lines
7.9 KiB
C

#ifndef SETUP_H
#define SETUP_H
#include "refs.h"
#include "string-list.h"
int is_inside_git_dir(void);
int is_inside_work_tree(void);
int get_common_dir_noenv(struct strbuf *sb, const char *gitdir);
int get_common_dir(struct strbuf *sb, const char *gitdir);
/*
* Return true if the given path is a git directory; note that this _just_
* looks at the directory itself. If you want to know whether "foo/.git"
* is a repository, you must feed that path, not just "foo".
*/
int is_git_directory(const char *path);
/*
* Return 1 if the given path is the root of a git repository or
* submodule, else 0. Will not return 1 for bare repositories with the
* exception of creating a bare repository in "foo/.git" and calling
* is_git_repository("foo").
*
* If we run into read errors, we err on the side of saying "yes, it is",
* as we usually consider sub-repos precious, and would prefer to err on the
* side of not disrupting or deleting them.
*/
int is_nonbare_repository_dir(struct strbuf *path);
#define READ_GITFILE_ERR_STAT_FAILED 1
#define READ_GITFILE_ERR_NOT_A_FILE 2
#define READ_GITFILE_ERR_OPEN_FAILED 3
#define READ_GITFILE_ERR_READ_FAILED 4
#define READ_GITFILE_ERR_INVALID_FORMAT 5
#define READ_GITFILE_ERR_NO_PATH 6
#define READ_GITFILE_ERR_NOT_A_REPO 7
#define READ_GITFILE_ERR_TOO_LARGE 8
void read_gitfile_error_die(int error_code, const char *path, const char *dir);
const char *read_gitfile_gently(const char *path, int *return_error_code);
#define read_gitfile(path) read_gitfile_gently((path), NULL)
const char *resolve_gitdir_gently(const char *suspect, int *return_error_code);
#define resolve_gitdir(path) resolve_gitdir_gently((path), NULL)
/*
* Check if a repository is safe and die if it is not, by verifying the
* ownership of the worktree (if any), the git directory, and the gitfile (if
* any).
*
* Exemptions for known-safe repositories can be added via `safe.directory`
* config settings; for non-bare repositories, their worktree needs to be
* added, for bare ones their git directory.
*/
void die_upon_dubious_ownership(const char *gitfile, const char *worktree,
const char *gitdir);
void setup_work_tree(void);
/*
* discover_git_directory_reason() is similar to discover_git_directory(),
* except it returns an enum value instead. It is important to note that
* a zero-valued return here is actually GIT_DIR_NONE, which is different
* from discover_git_directory.
*/
enum discovery_result {
GIT_DIR_EXPLICIT = 1,
GIT_DIR_DISCOVERED = 2,
GIT_DIR_BARE = 3,
/* these are errors */
GIT_DIR_HIT_CEILING = -1,
GIT_DIR_HIT_MOUNT_POINT = -2,
GIT_DIR_INVALID_GITFILE = -3,
GIT_DIR_INVALID_OWNERSHIP = -4,
GIT_DIR_DISALLOWED_BARE = -5,
GIT_DIR_INVALID_FORMAT = -6,
GIT_DIR_CWD_FAILURE = -7,
};
enum discovery_result discover_git_directory_reason(struct strbuf *commondir,
struct strbuf *gitdir);
/*
* Find the commondir and gitdir of the repository that contains the current
* working directory, without changing the working directory or other global
* state. The result is appended to commondir and gitdir. If the discovered
* gitdir does not correspond to a worktree, then 'commondir' and 'gitdir' will
* both have the same result appended to the buffer. The return value is
* either 0 upon success and -1 if no repository was found.
*/
static inline int discover_git_directory(struct strbuf *commondir,
struct strbuf *gitdir)
{
if (discover_git_directory_reason(commondir, gitdir) <= 0)
return -1;
return 0;
}
void set_git_dir(const char *path, int make_realpath);
void set_git_work_tree(const char *tree);
const char *setup_git_directory_gently(int *);
const char *setup_git_directory(void);
char *prefix_path(const char *prefix, int len, const char *path);
char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
int check_filename(const char *prefix, const char *name);
void verify_filename(const char *prefix,
const char *name,
int diagnose_misspelt_rev);
void verify_non_filename(const char *prefix, const char *name);
int path_inside_repo(const char *prefix, const char *path);
void sanitize_stdfds(void);
int daemonize(void);
/*
* GIT_REPO_VERSION is the version we write by default. The
* _READ variant is the highest number we know how to
* handle.
*/
#define GIT_REPO_VERSION 0
#define GIT_REPO_VERSION_READ 1
/*
* You _have_ to initialize a `struct repository_format` using
* `= REPOSITORY_FORMAT_INIT` before calling `read_repository_format()`.
*/
struct repository_format {
int version;
int precious_objects;
char *partial_clone; /* value of extensions.partialclone */
int worktree_config;
int relative_worktrees;
int is_bare;
int hash_algo;
int compat_hash_algo;
enum ref_storage_format ref_storage_format;
int sparse_index;
char *work_tree;
struct string_list unknown_extensions;
struct string_list v1_only_extensions;
};
/*
* Always use this to initialize a `struct repository_format`
* to a well-defined, default state before calling
* `read_repository()`.
*/
#define REPOSITORY_FORMAT_INIT \
{ \
.version = -1, \
.is_bare = -1, \
.hash_algo = GIT_HASH_DEFAULT, \
.ref_storage_format = REF_STORAGE_FORMAT_FILES, \
.unknown_extensions = STRING_LIST_INIT_DUP, \
.v1_only_extensions = STRING_LIST_INIT_DUP, \
}
/*
* Read the repository format characteristics from the config file "path" into
* "format" struct. Returns the numeric version. On error, or if no version is
* found in the configuration, -1 is returned, format->version is set to -1,
* and all other fields in the struct are set to the default configuration
* (REPOSITORY_FORMAT_INIT). Always initialize the struct using
* REPOSITORY_FORMAT_INIT before calling this function.
*/
int read_repository_format(struct repository_format *format, const char *path);
/*
* Free the memory held onto by `format`, but not the struct itself.
* (No need to use this after `read_repository_format()` fails.)
*/
void clear_repository_format(struct repository_format *format);
/*
* Verify that the repository described by repository_format is something we
* can read. If it is, return 0. Otherwise, return -1, and "err" will describe
* any errors encountered.
*/
int verify_repository_format(const struct repository_format *format,
struct strbuf *err);
/*
* Check the repository format version in the path found in repo_get_git_dir(the_repository),
* and die if it is a version we don't understand. Generally one would
* set_git_dir() before calling this, and use it only for "are we in a valid
* repo?".
*
* If successful and fmt is not NULL, fill fmt with data.
*/
void check_repository_format(struct repository_format *fmt);
const char *get_template_dir(const char *option_template);
#define INIT_DB_QUIET (1 << 0)
#define INIT_DB_EXIST_OK (1 << 1)
#define INIT_DB_SKIP_REFDB (1 << 2)
int init_db(const char *git_dir, const char *real_git_dir,
const char *template_dir, int hash_algo,
enum ref_storage_format ref_storage_format,
const char *initial_branch, int init_shared_repository,
unsigned int flags);
void initialize_repository_version(int hash_algo,
enum ref_storage_format ref_storage_format,
int reinit);
void create_reference_database(enum ref_storage_format ref_storage_format,
const char *initial_branch, int quiet);
/*
* NOTE NOTE NOTE!!
*
* PERM_UMASK, OLD_PERM_GROUP and OLD_PERM_EVERYBODY enumerations must
* not be changed. Old repositories have core.sharedrepository written in
* numeric format, and therefore these values are preserved for compatibility
* reasons.
*/
enum sharedrepo {
PERM_UMASK = 0,
OLD_PERM_GROUP = 1,
OLD_PERM_EVERYBODY = 2,
PERM_GROUP = 0660,
PERM_EVERYBODY = 0664
};
int git_config_perm(const char *var, const char *value);
struct startup_info {
int have_repository;
const char *prefix;
const char *original_cwd;
};
extern struct startup_info *startup_info;
extern const char *tmp_original_cwd;
#endif /* SETUP_H */