setup.h

#ifndef SETUP_H
#define SETUP_H

#include "refs.h"
#include "string-list.h"

int is_inside_git_dir(struct repository *repo);
int is_inside_work_tree(struct repository *repo);
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
#define READ_GITFILE_ERR_MISSING 9
#define READ_GITFILE_ERR_IS_A_DIR 10
void read_gitfile_error_die(int error_code, const char *path);
const char *read_gitfile_gently(const char *path, int *return_error_code);
int read_gitfile_raw(struct strbuf *contents, const char *path);
#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(struct repository *repo);

/*
 * 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;
}

/* Flags that can be passed to `enter_repo()`. */
enum {
	/*
	 * Callers that require exact paths (as opposed to allowing known
	 * suffixes like ".git", ".git/.git" to be omitted) can set this bit.
	 */
	ENTER_REPO_STRICT = (1<<0),

	/*
	 * Callers that are willing to run without ownership check can set this
	 * bit.
	 */
	ENTER_REPO_ANY_OWNER_OK = (1<<1),
};

/*
 * Discover and enter a repository.
 *
 * First, one directory to try is determined by the following algorithm.
 *
 * (0) If "strict" is given, the path is used as given and no DWIM is
 *     done. Otherwise:
 * (1) "~/path" to mean path under the running user's home directory;
 * (2) "~user/path" to mean path under named user's home directory;
 * (3) "relative/path" to mean cwd relative directory; or
 * (4) "/absolute/path" to mean absolute directory.
 *
 * Unless "strict" is given, we check "%s/.git", "%s", "%s.git/.git", "%s.git"
 * in this order. We select the first one that is a valid git repository, and
 * chdir() to it. If none match, or we fail to chdir, we return NULL.
 *
 * If all goes well, we return the directory we used to chdir() (but
 * before ~user is expanded), avoiding getcwd() resolving symbolic
 * links.  User relative paths are also returned as they are given,
 * except DWIM suffixing.
 */
const char *enter_repo(struct repository *repo, const char *path, unsigned flags);

const char *setup_git_directory_gently(struct repository *repo, int *);
const char *setup_git_directory(struct repository *repo);
char *prefix_path(struct repository *repo, const char *prefix, int len, const char *path);
char *prefix_path_gently(struct repository *repo, const char *prefix, int len, int *remaining, const char *path);

int check_filename(const char *prefix, const char *name);
void verify_filename(struct repository *repo,
		     const char *prefix,
		     const char *name,
		     int diagnose_misspelt_rev);
void verify_non_filename(struct repository *repo, const char *prefix, const char *name);
int path_inside_repo(struct repository *repo, const char *prefix, const char *path);

void sanitize_stdfds(void);

/*
 * Daemonize the current process by forking and then exiting the parent
 * process. Returns 0 when successful, in which case the parent process will
 * have exited and it's the child process that continues to run the code.
 * Otherwise, a negative error code is returned and the parent process will
 * continue execution.
 *
 * Note that this function will also perform the following changes:
 *
 *   - Standard file descriptors in the child process are closed.
 *   - The child process is made a session leader via setsid(3p).
 *   - All tempfiles owned by the parent process are reassigned to the
 *     daemonized child process.
 */
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 submodule_path_cfg;
	int is_bare;
	int hash_algo;
	int compat_hash_algo;
	enum ref_storage_format ref_storage_format;
	char *ref_storage_payload;
	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);

enum apply_repository_format_flags {
	/*
	 * Honor environment variables when applying the repository format to
	 * the repository. For now, this only covers environment variables that
	 * relate to the object database.
	 */
	APPLY_REPOSITORY_FORMAT_HONOR_ENV = (1 << 0),
};

/*
 * Apply the given repository format to the repo. This initializes extensions
 * required for normal operation. Returns 0 on success, a negative error code
 * when the format is not valid as determined by
 * `verify_repository_format()`.
 */
int apply_repository_format(struct repository *repo,
			    const struct repository_format *format,
			    enum apply_repository_format_flags flags,
			    struct strbuf *err);

const char *get_template_dir(const char *option_template);

/*
 * Create the repository by creating the necessary directory structures,
 * setting up the configuration and configuring the repository's format. If
 * `template_dir` is set, copy over templates from that directory. Furthermore,
 * if and only if `reinit_ok` is a non-NULL pointer, then the function may
 * reinitialize a preexisting repository. In that case, the pointer will be set
 * to `1` in case the repo was reinitialized and `0` if it didn't exist yet.
 *
 * Note that this function does not create the reference and object databases.
 */
void create_repository(struct repository *repo,
		       const char *git_dir,
		       const char *real_git_dir,
		       const char *worktree,
		       const char *template_dir,
		       int hash_algo,
		       const char *ref_storage_format_uri,
		       int init_shared_repository,
		       int *reinit_ok);

void initialize_repository_version(struct repository *repo,
				   int hash_algo,
				   enum ref_storage_format ref_storage_format,
				   int reinit);

/*
 * Create the reference database for the repository. The repository and its ref
 * storage format must have already been configured properly before calling
 * this function. When set, `initial_branch` overrides the default branch that
 * HEAD will point to.
 */
void create_reference_database(struct repository *repo, const char *initial_branch, int quiet);

/*
 * Create the object database for the repository. The repository must have
 * already been configured properly before calling this function. When set,
 * `alternates` is the list of alternates that should be written into the
 * object database.
 */
void create_object_database(struct repository *repo, const struct strvec *alternates);

/*
 * 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 {
	/*
	 * Whether the user is asking us to treat the repository as bare via
	 * `git --bare`, even if it's not.
	 */
	bool force_bare_repository;

	int have_repository;
	const char *original_cwd;
};
extern struct startup_info *startup_info;
extern const char *tmp_original_cwd;

#endif /* SETUP_H */