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| -rw-r--r-- | refs.h | 999 |
1 files changed, 999 insertions, 0 deletions
@@ -0,0 +1,999 @@ +#ifndef REFS_H +#define REFS_H + +#include "cache.h" +#include "commit.h" + +struct object_id; +struct ref_store; +struct repository; +struct strbuf; +struct string_list; +struct string_list_item; +struct worktree; + +/* + * Resolve a reference, recursively following symbolic refererences. + * + * Return the name of the non-symbolic reference that ultimately pointed + * at the resolved object name. The return value, if not NULL, is a + * pointer into either a static buffer or the input ref. + * + * If oid is non-NULL, store the referred-to object's name in it. + * + * If the reference cannot be resolved to an object, the behavior + * depends on the RESOLVE_REF_READING flag: + * + * - If RESOLVE_REF_READING is set, return NULL. + * + * - If RESOLVE_REF_READING is not set, clear oid and return the name of + * the last reference name in the chain, which will either be a non-symbolic + * reference or an undefined reference. If this is a prelude to + * "writing" to the ref, the return value is the name of the ref + * that will actually be created or changed. + * + * If the RESOLVE_REF_NO_RECURSE flag is passed, only resolves one + * level of symbolic reference. The value stored in oid for a symbolic + * reference will always be null_oid in this case, and the return + * value is the reference that the symref refers to directly. + * + * If flags is non-NULL, set the value that it points to the + * combination of REF_ISPACKED (if the reference was found among the + * packed references), REF_ISSYMREF (if the initial reference was a + * symbolic reference), REF_BAD_NAME (if the reference name is ill + * formed --- see RESOLVE_REF_ALLOW_BAD_NAME below), and REF_ISBROKEN + * (if the ref is malformed or has a bad name). See refs.h for more detail + * on each flag. + * + * If ref is not a properly-formatted, normalized reference, return + * NULL. If more than MAXDEPTH recursive symbolic lookups are needed, + * give up and return NULL. + * + * RESOLVE_REF_ALLOW_BAD_NAME allows resolving refs even when their + * name is invalid according to git-check-ref-format(1). If the name + * is bad then the value stored in oid will be null_oid and the two + * flags REF_ISBROKEN and REF_BAD_NAME will be set. + * + * Even with RESOLVE_REF_ALLOW_BAD_NAME, names that escape the refs/ + * directory and do not consist of all caps and underscores cannot be + * resolved. The function returns NULL for such ref names. + * Caps and underscores refers to the special refs, such as HEAD, + * FETCH_HEAD and friends, that all live outside of the refs/ directory. + */ +#define RESOLVE_REF_READING 0x01 +#define RESOLVE_REF_NO_RECURSE 0x02 +#define RESOLVE_REF_ALLOW_BAD_NAME 0x04 + +const char *refs_resolve_ref_unsafe(struct ref_store *refs, + const char *refname, + int resolve_flags, + struct object_id *oid, + int *flags); + +const char *resolve_ref_unsafe(const char *refname, int resolve_flags, + struct object_id *oid, int *flags); + +char *refs_resolve_refdup(struct ref_store *refs, + const char *refname, int resolve_flags, + struct object_id *oid, int *flags); +char *resolve_refdup(const char *refname, int resolve_flags, + struct object_id *oid, int *flags); + +int read_ref_full(const char *refname, int resolve_flags, + struct object_id *oid, int *flags); +int read_ref(const char *refname, struct object_id *oid); + +int refs_read_symbolic_ref(struct ref_store *ref_store, const char *refname, + struct strbuf *referent); + +/* + * Return 0 if a reference named refname could be created without + * conflicting with the name of an existing reference. Otherwise, + * return a negative value and write an explanation to err. If extras + * is non-NULL, it is a list of additional refnames with which refname + * is not allowed to conflict. If skip is non-NULL, ignore potential + * conflicts with refs in skip (e.g., because they are scheduled for + * deletion in the same operation). Behavior is undefined if the same + * name is listed in both extras and skip. + * + * Two reference names conflict if one of them exactly matches the + * leading components of the other; e.g., "foo/bar" conflicts with + * both "foo" and with "foo/bar/baz" but not with "foo/bar" or + * "foo/barbados". + * + * extras and skip must be sorted. + */ + +int refs_verify_refname_available(struct ref_store *refs, + const char *refname, + const struct string_list *extras, + const struct string_list *skip, + struct strbuf *err); + +int refs_ref_exists(struct ref_store *refs, const char *refname); + +int ref_exists(const char *refname); + +int should_autocreate_reflog(const char *refname); + +int is_branch(const char *refname); + +int refs_init_db(struct strbuf *err); + +/* + * Return the peeled value of the oid currently being iterated via + * for_each_ref(), etc. This is equivalent to calling: + * + * peel_object(oid, &peeled); + * + * with the "oid" value given to the each_ref_fn callback, except + * that some ref storage may be able to answer the query without + * actually loading the object in memory. + */ +int peel_iterated_oid(const struct object_id *base, struct object_id *peeled); + +/** + * Resolve refname in the nested "gitlink" repository in the specified + * submodule (which must be non-NULL). If the resolution is + * successful, return 0 and set oid to the name of the object; + * otherwise, return a non-zero value. + */ +int resolve_gitlink_ref(const char *submodule, const char *refname, + struct object_id *oid); + +/* + * Return true iff abbrev_name is a possible abbreviation for + * full_name according to the rules defined by ref_rev_parse_rules in + * refs.c. + */ +int refname_match(const char *abbrev_name, const char *full_name); + +/* + * Given a 'prefix' expand it by the rules in 'ref_rev_parse_rules' and add + * the results to 'prefixes' + */ +struct strvec; +void expand_ref_prefix(struct strvec *prefixes, const char *prefix); + +int expand_ref(struct repository *r, const char *str, int len, struct object_id *oid, char **ref); +int repo_dwim_ref(struct repository *r, const char *str, int len, + struct object_id *oid, char **ref, int nonfatal_dangling_mark); +int repo_dwim_log(struct repository *r, const char *str, int len, struct object_id *oid, char **ref); +static inline int dwim_ref(const char *str, int len, struct object_id *oid, + char **ref, int nonfatal_dangling_mark) +{ + return repo_dwim_ref(the_repository, str, len, oid, ref, + nonfatal_dangling_mark); +} +int dwim_log(const char *str, int len, struct object_id *oid, char **ref); + +/* + * Retrieves the default branch name for newly-initialized repositories. + * + * The return value of `repo_default_branch_name()` is an allocated string. The + * return value of `git_default_branch_name()` is a singleton. + */ +const char *git_default_branch_name(int quiet); +char *repo_default_branch_name(struct repository *r, int quiet); + +/* + * A ref_transaction represents a collection of reference updates that + * should succeed or fail together. + * + * Calling sequence + * ---------------- + * + * - Allocate and initialize a `struct ref_transaction` by calling + * `ref_transaction_begin()`. + * + * - Specify the intended ref updates by calling one or more of the + * following functions: + * - `ref_transaction_update()` + * - `ref_transaction_create()` + * - `ref_transaction_delete()` + * - `ref_transaction_verify()` + * + * - Then either: + * + * - Optionally call `ref_transaction_prepare()` to prepare the + * transaction. This locks all references, checks preconditions, + * etc. but doesn't finalize anything. If this step fails, the + * transaction has been closed and can only be freed. If this step + * succeeds, then `ref_transaction_commit()` is almost certain to + * succeed. However, you can still call `ref_transaction_abort()` + * if you decide not to commit the transaction after all. + * + * - Call `ref_transaction_commit()` to execute the transaction, + * make the changes permanent, and release all locks. If you + * haven't already called `ref_transaction_prepare()`, then + * `ref_transaction_commit()` calls it for you. + * + * Or + * + * - Call `initial_ref_transaction_commit()` if the ref database is + * known to be empty and have no other writers (e.g. during + * clone). This is likely to be much faster than + * `ref_transaction_commit()`. `ref_transaction_prepare()` should + * *not* be called before `initial_ref_transaction_commit()`. + * + * - Then finally, call `ref_transaction_free()` to free the + * `ref_transaction` data structure. + * + * At any time before calling `ref_transaction_commit()`, you can call + * `ref_transaction_abort()` to abort the transaction, rollback any + * locks, and free any associated resources (including the + * `ref_transaction` data structure). + * + * Putting it all together, a complete reference update looks like + * + * struct ref_transaction *transaction; + * struct strbuf err = STRBUF_INIT; + * int ret = 0; + * + * transaction = ref_store_transaction_begin(refs, &err); + * if (!transaction || + * ref_transaction_update(...) || + * ref_transaction_create(...) || + * ...etc... || + * ref_transaction_commit(transaction, &err)) { + * error("%s", err.buf); + * ret = -1; + * } + * ref_transaction_free(transaction); + * strbuf_release(&err); + * return ret; + * + * Error handling + * -------------- + * + * On error, transaction functions append a message about what + * went wrong to the 'err' argument. The message mentions what + * ref was being updated (if any) when the error occurred so it + * can be passed to 'die' or 'error' as-is. + * + * The message is appended to err without first clearing err. + * err will not be '\n' terminated. + * + * Caveats + * ------- + * + * Note that no locks are taken, and no refs are read, until + * `ref_transaction_prepare()` or `ref_transaction_commit()` is + * called. So, for example, `ref_transaction_verify()` won't report a + * verification failure until the commit is attempted. + */ +struct ref_transaction; + +/* + * Bit values set in the flags argument passed to each_ref_fn() and + * stored in ref_iterator::flags. Other bits are for internal use + * only: + */ + +/* Reference is a symbolic reference. */ +#define REF_ISSYMREF 0x01 + +/* Reference is a packed reference. */ +#define REF_ISPACKED 0x02 + +/* + * Reference cannot be resolved to an object name: dangling symbolic + * reference (directly or indirectly), corrupt reference file, + * reference exists but name is bad, or symbolic reference refers to + * ill-formatted reference name. + */ +#define REF_ISBROKEN 0x04 + +/* + * Reference name is not well formed. + * + * See git-check-ref-format(1) for the definition of well formed ref names. + */ +#define REF_BAD_NAME 0x08 + +/* + * The signature for the callback function for the for_each_*() + * functions below. The memory pointed to by the refname and oid + * arguments is only guaranteed to be valid for the duration of a + * single callback invocation. + */ +typedef int each_ref_fn(const char *refname, + const struct object_id *oid, int flags, void *cb_data); + +/* + * The same as each_ref_fn, but also with a repository argument that + * contains the repository associated with the callback. + */ +typedef int each_repo_ref_fn(struct repository *r, + const char *refname, + const struct object_id *oid, + int flags, + void *cb_data); + +/* + * The following functions invoke the specified callback function for + * each reference indicated. If the function ever returns a nonzero + * value, stop the iteration and return that value. Please note that + * it is not safe to modify references while an iteration is in + * progress, unless the same callback function invocation that + * modifies the reference also returns a nonzero value to immediately + * stop the iteration. Returned references are sorted. + */ +int refs_head_ref(struct ref_store *refs, + each_ref_fn fn, void *cb_data); +int refs_for_each_ref(struct ref_store *refs, + each_ref_fn fn, void *cb_data); +int refs_for_each_ref_in(struct ref_store *refs, const char *prefix, + each_ref_fn fn, void *cb_data); +int refs_for_each_tag_ref(struct ref_store *refs, + each_ref_fn fn, void *cb_data); +int refs_for_each_branch_ref(struct ref_store *refs, + each_ref_fn fn, void *cb_data); +int refs_for_each_remote_ref(struct ref_store *refs, + each_ref_fn fn, void *cb_data); + +/* just iterates the head ref. */ +int head_ref(each_ref_fn fn, void *cb_data); + +/* iterates all refs. */ +int for_each_ref(each_ref_fn fn, void *cb_data); + +/** + * iterates all refs which have a defined prefix and strips that prefix from + * the passed variable refname. + */ +int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data); + +int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix, + each_ref_fn fn, void *cb_data); +int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data); + +/** + * iterate all refs in "patterns" by partitioning patterns into disjoint sets + * and iterating the longest-common prefix of each set. + * + * callers should be prepared to ignore references that they did not ask for. + */ +int for_each_fullref_in_prefixes(const char *namespace, const char **patterns, + each_ref_fn fn, void *cb_data); +/** + * iterate refs from the respective area. + */ +int for_each_tag_ref(each_ref_fn fn, void *cb_data); +int for_each_branch_ref(each_ref_fn fn, void *cb_data); +int for_each_remote_ref(each_ref_fn fn, void *cb_data); +int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data); + +/* iterates all refs that match the specified glob pattern. */ +int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data); + +int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, + const char *prefix, void *cb_data); + +int head_ref_namespaced(each_ref_fn fn, void *cb_data); +int for_each_namespaced_ref(each_ref_fn fn, void *cb_data); + +/* can be used to learn about broken ref and symref */ +int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data); +int for_each_rawref(each_ref_fn fn, void *cb_data); + +/* + * Normalizes partial refs to their fully qualified form. + * Will prepend <prefix> to the <pattern> if it doesn't start with 'refs/'. + * <prefix> will default to 'refs/' if NULL. + * + * item.string will be set to the result. + * item.util will be set to NULL if <pattern> contains glob characters, or + * non-NULL if it doesn't. + */ +void normalize_glob_ref(struct string_list_item *item, const char *prefix, + const char *pattern); + +static inline const char *has_glob_specials(const char *pattern) +{ + return strpbrk(pattern, "?*["); +} + +void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname); +void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, + const struct string_list *refnames); + +/* + * Flags for controlling behaviour of pack_refs() + * PACK_REFS_PRUNE: Prune loose refs after packing + * PACK_REFS_ALL: Pack _all_ refs, not just tags and already packed refs + */ +#define PACK_REFS_PRUNE 0x0001 +#define PACK_REFS_ALL 0x0002 + +/* + * Write a packed-refs file for the current repository. + * flags: Combination of the above PACK_REFS_* flags. + */ +int refs_pack_refs(struct ref_store *refs, unsigned int flags); + +/* + * Setup reflog before using. Fill in err and return -1 on failure. + */ +int refs_create_reflog(struct ref_store *refs, const char *refname, + struct strbuf *err); +int safe_create_reflog(const char *refname, struct strbuf *err); + +/** Reads log for the value of ref during at_time. **/ +int read_ref_at(struct ref_store *refs, + const char *refname, unsigned int flags, + timestamp_t at_time, int cnt, + struct object_id *oid, char **msg, + timestamp_t *cutoff_time, int *cutoff_tz, int *cutoff_cnt); + +/** Check if a particular reflog exists */ +int refs_reflog_exists(struct ref_store *refs, const char *refname); +int reflog_exists(const char *refname); + +/* + * Delete the specified reference. If old_oid is non-NULL, then + * verify that the current value of the reference is old_oid before + * deleting it. If old_oid is NULL, delete the reference if it + * exists, regardless of its old value. It is an error for old_oid to + * be null_oid. msg and flags are passed through to + * ref_transaction_delete(). + */ +int refs_delete_ref(struct ref_store *refs, const char *msg, + const char *refname, + const struct object_id *old_oid, + unsigned int flags); +int delete_ref(const char *msg, const char *refname, + const struct object_id *old_oid, unsigned int flags); + +/* + * Delete the specified references. If there are any problems, emit + * errors but attempt to keep going (i.e., the deletes are not done in + * an all-or-nothing transaction). msg and flags are passed through to + * ref_transaction_delete(). + */ +int refs_delete_refs(struct ref_store *refs, const char *msg, + struct string_list *refnames, unsigned int flags); +int delete_refs(const char *msg, struct string_list *refnames, + unsigned int flags); + +/** Delete a reflog */ +int refs_delete_reflog(struct ref_store *refs, const char *refname); +int delete_reflog(const char *refname); + +/* + * Callback to process a reflog entry found by the iteration functions (see + * below). + * + * The committer parameter is a single string, in the form + * "$GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL>" (without double quotes). + * + * The timestamp parameter gives the time when entry was created as the number + * of seconds since the UNIX epoch. + * + * The tz parameter gives the timezone offset for the user who created + * the reflog entry, and its value gives a positive or negative offset + * from UTC. Its absolute value is formed by multiplying the hour + * part by 100 and adding the minute part. For example, 1 hour ahead + * of UTC, CET == "+0100", is represented as positive one hundred (not + * postiive sixty). + * + * The msg parameter is a single complete line; a reflog message given + * to refs_delete_ref, refs_update_ref, etc. is returned to the + * callback normalized---each run of whitespaces are squashed into a + * single whitespace, trailing whitespace, if exists, is trimmed, and + * then a single LF is added at the end. + * + * The cb_data is a caller-supplied pointer given to the iterator + * functions. + */ +typedef int each_reflog_ent_fn( + struct object_id *old_oid, struct object_id *new_oid, + const char *committer, timestamp_t timestamp, + int tz, const char *msg, void *cb_data); + +/* Iterate over reflog entries in the log for `refname`. */ + +/* oldest entry first */ +int refs_for_each_reflog_ent(struct ref_store *refs, const char *refname, + each_reflog_ent_fn fn, void *cb_data); + +/* youngest entry first */ +int refs_for_each_reflog_ent_reverse(struct ref_store *refs, + const char *refname, + each_reflog_ent_fn fn, + void *cb_data); + +/* + * Iterate over reflog entries in the log for `refname` in the main ref store. + */ + +/* oldest entry first */ +int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data); + +/* youngest entry first */ +int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data); + +/* + * Calls the specified function for each reflog file until it returns nonzero, + * and returns the value. Reflog file order is unspecified. + */ +int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data); +int for_each_reflog(each_ref_fn fn, void *cb_data); + +#define REFNAME_ALLOW_ONELEVEL 1 +#define REFNAME_REFSPEC_PATTERN 2 + +/* + * Return 0 iff refname has the correct format for a refname according + * to the rules described in Documentation/git-check-ref-format.txt. + * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level + * reference names. If REFNAME_REFSPEC_PATTERN is set in flags, then + * allow a single "*" wildcard character in the refspec. No leading or + * repeated slashes are accepted. + */ +int check_refname_format(const char *refname, int flags); + +/* + * Apply the rules from check_refname_format, but mutate the result until it + * is acceptable, and place the result in "out". + */ +void sanitize_refname_component(const char *refname, struct strbuf *out); + +const char *prettify_refname(const char *refname); + +char *refs_shorten_unambiguous_ref(struct ref_store *refs, + const char *refname, int strict); +char *shorten_unambiguous_ref(const char *refname, int strict); + +/** rename ref, return 0 on success **/ +int refs_rename_ref(struct ref_store *refs, const char *oldref, + const char *newref, const char *logmsg); +int rename_ref(const char *oldref, const char *newref, + const char *logmsg); + +/** copy ref, return 0 on success **/ +int refs_copy_existing_ref(struct ref_store *refs, const char *oldref, + const char *newref, const char *logmsg); +int copy_existing_ref(const char *oldref, const char *newref, + const char *logmsg); + +int refs_create_symref(struct ref_store *refs, const char *refname, + const char *target, const char *logmsg); +int create_symref(const char *refname, const char *target, const char *logmsg); + +enum action_on_err { + UPDATE_REFS_MSG_ON_ERR, + UPDATE_REFS_DIE_ON_ERR, + UPDATE_REFS_QUIET_ON_ERR +}; + +/* + * Begin a reference transaction. The reference transaction must + * be freed by calling ref_transaction_free(). + */ +struct ref_transaction *ref_store_transaction_begin(struct ref_store *refs, + struct strbuf *err); +struct ref_transaction *ref_transaction_begin(struct strbuf *err); + +/* + * Reference transaction updates + * + * The following four functions add a reference check or update to a + * ref_transaction. They have some common similar parameters: + * + * transaction -- a pointer to an open ref_transaction, obtained + * from ref_transaction_begin(). + * + * refname -- the name of the reference to be affected. + * + * new_oid -- the object ID that should be set to be the new value + * of the reference. Some functions allow this parameter to be + * NULL, meaning that the reference is not changed, or + * null_oid, meaning that the reference should be deleted. A + * copy of this value is made in the transaction. + * + * old_oid -- the object ID that the reference must have before + * the update. Some functions allow this parameter to be NULL, + * meaning that the old value of the reference is not checked, + * or null_oid, meaning that the reference must not exist + * before the update. A copy of this value is made in the + * transaction. + * + * flags -- flags affecting the update, passed to + * update_ref_lock(). Possible flags: REF_NO_DEREF, + * REF_FORCE_CREATE_REFLOG. See those constants for more + * information. + * + * msg -- a message describing the change (for the reflog). + * + * err -- a strbuf for receiving a description of any error that + * might have occurred. + * + * The functions make internal copies of refname and msg, so the + * caller retains ownership of these parameters. + * + * The functions return 0 on success and non-zero on failure. A + * failure means that the transaction as a whole has failed and needs + * to be rolled back. + */ + +/* + * The following flags can be passed to ref_transaction_update() etc. + * Internally, they are stored in `ref_update::flags`, along with some + * internal flags. + */ + +/* + * Act on the ref directly; i.e., without dereferencing symbolic refs. + * If this flag is not specified, then symbolic references are + * dereferenced and the update is applied to the referent. + */ +#define REF_NO_DEREF (1 << 0) + +/* + * Force the creation of a reflog for this reference, even if it + * didn't previously have a reflog. + */ +#define REF_FORCE_CREATE_REFLOG (1 << 1) + +/* + * Blindly write an object_id. This is useful for testing data corruption + * scenarios. + */ +#define REF_SKIP_OID_VERIFICATION (1 << 10) + +/* + * Skip verifying refname. This is useful for testing data corruption scenarios. + */ +#define REF_SKIP_REFNAME_VERIFICATION (1 << 11) + +/* + * Bitmask of all of the flags that are allowed to be passed in to + * ref_transaction_update() and friends: + */ +#define REF_TRANSACTION_UPDATE_ALLOWED_FLAGS \ + (REF_NO_DEREF | REF_FORCE_CREATE_REFLOG | REF_SKIP_OID_VERIFICATION | \ + REF_SKIP_REFNAME_VERIFICATION) + +/* + * Add a reference update to transaction. `new_oid` is the value that + * the reference should have after the update, or `null_oid` if it + * should be deleted. If `new_oid` is NULL, then the reference is not + * changed at all. `old_oid` is the value that the reference must have + * before the update, or `null_oid` if it must not have existed + * beforehand. The old value is checked after the lock is taken to + * prevent races. If the old value doesn't agree with old_oid, the + * whole transaction fails. If old_oid is NULL, then the previous + * value is not checked. + * + * See the above comment "Reference transaction updates" for more + * information. + */ +int ref_transaction_update(struct ref_transaction *transaction, + const char *refname, + const struct object_id *new_oid, + const struct object_id *old_oid, + unsigned int flags, const char *msg, + struct strbuf *err); + +/* + * Add a reference creation to transaction. new_oid is the value that + * the reference should have after the update; it must not be + * null_oid. It is verified that the reference does not exist + * already. + * + * See the above comment "Reference transaction updates" for more + * information. + */ +int ref_transaction_create(struct ref_transaction *transaction, + const char *refname, + const struct object_id *new_oid, + unsigned int flags, const char *msg, + struct strbuf *err); + +/* + * Add a reference deletion to transaction. If old_oid is non-NULL, + * then it holds the value that the reference should have had before + * the update (which must not be null_oid). + * + * See the above comment "Reference transaction updates" for more + * information. + */ +int ref_transaction_delete(struct ref_transaction *transaction, + const char *refname, + const struct object_id *old_oid, + unsigned int flags, const char *msg, + struct strbuf *err); + +/* + * Verify, within a transaction, that refname has the value old_oid, + * or, if old_oid is null_oid, then verify that the reference + * doesn't exist. old_oid must be non-NULL. + * + * See the above comment "Reference transaction updates" for more + * information. + */ +int ref_transaction_verify(struct ref_transaction *transaction, + const char *refname, + const struct object_id *old_oid, + unsigned int flags, + struct strbuf *err); + +/* Naming conflict (for example, the ref names A and A/B conflict). */ +#define TRANSACTION_NAME_CONFLICT -1 +/* All other errors. */ +#define TRANSACTION_GENERIC_ERROR -2 + +/* + * Perform the preparatory stages of committing `transaction`. Acquire + * any needed locks, check preconditions, etc.; basically, do as much + * as possible to ensure that the transaction will be able to go + * through, stopping just short of making any irrevocable or + * user-visible changes. The updates that this function prepares can + * be finished up by calling `ref_transaction_commit()` or rolled back + * by calling `ref_transaction_abort()`. + * + * On success, return 0 and leave the transaction in "prepared" state. + * On failure, abort the transaction, write an error message to `err`, + * and return one of the `TRANSACTION_*` constants. + * + * Callers who don't need such fine-grained control over committing + * reference transactions should just call `ref_transaction_commit()`. + */ +int ref_transaction_prepare(struct ref_transaction *transaction, + struct strbuf *err); + +/* + * Commit all of the changes that have been queued in transaction, as + * atomically as possible. On success, return 0 and leave the + * transaction in "closed" state. On failure, roll back the + * transaction, write an error message to `err`, and return one of the + * `TRANSACTION_*` constants + */ +int ref_transaction_commit(struct ref_transaction *transaction, + struct strbuf *err); + +/* + * Abort `transaction`, which has been begun and possibly prepared, + * but not yet committed. + */ +int ref_transaction_abort(struct ref_transaction *transaction, + struct strbuf *err); + +/* + * Like ref_transaction_commit(), but optimized for creating + * references when originally initializing a repository (e.g., by "git + * clone"). It writes the new references directly to packed-refs + * without locking the individual references. + * + * It is a bug to call this function when there might be other + * processes accessing the repository or if there are existing + * references that might conflict with the ones being created. All + * old_oid values must either be absent or null_oid. + */ +int initial_ref_transaction_commit(struct ref_transaction *transaction, + struct strbuf *err); + +/* + * Execute the given callback function for each of the reference updates which + * have been queued in the given transaction. `old_oid` and `new_oid` may be + * `NULL` pointers depending on whether the update has these object IDs set or + * not. + */ +typedef void ref_transaction_for_each_queued_update_fn(const char *refname, + const struct object_id *old_oid, + const struct object_id *new_oid, + void *cb_data); +void ref_transaction_for_each_queued_update(struct ref_transaction *transaction, + ref_transaction_for_each_queued_update_fn cb, + void *cb_data); + +/* + * Free `*transaction` and all associated data. + */ +void ref_transaction_free(struct ref_transaction *transaction); + +/** + * Lock, update, and unlock a single reference. This function + * basically does a transaction containing a single call to + * ref_transaction_update(). The parameters to this function have the + * same meaning as the corresponding parameters to + * ref_transaction_update(). Handle errors as requested by the `onerr` + * argument. + */ +int refs_update_ref(struct ref_store *refs, const char *msg, const char *refname, + const struct object_id *new_oid, const struct object_id *old_oid, + unsigned int flags, enum action_on_err onerr); +int update_ref(const char *msg, const char *refname, + const struct object_id *new_oid, const struct object_id *old_oid, + unsigned int flags, enum action_on_err onerr); + +int parse_hide_refs_config(const char *var, const char *value, const char *, + struct string_list *); + +/* + * Check whether a ref is hidden. If no namespace is set, both the first and + * the second parameter point to the full ref name. If a namespace is set and + * the ref is inside that namespace, the first parameter is a pointer to the + * name of the ref with the namespace prefix removed. If a namespace is set and + * the ref is outside that namespace, the first parameter is NULL. The second + * parameter always points to the full ref name. + */ +int ref_is_hidden(const char *, const char *, const struct string_list *); + +/* Is this a per-worktree ref living in the refs/ namespace? */ +int is_per_worktree_ref(const char *refname); + +/* Describes how a refname relates to worktrees */ +enum ref_worktree_type { + REF_WORKTREE_CURRENT, /* implicitly per worktree, eg. HEAD or + refs/bisect/SOMETHING */ + REF_WORKTREE_MAIN, /* explicitly in main worktree, eg. + main-worktree/HEAD */ + REF_WORKTREE_OTHER, /* explicitly in named worktree, eg. + worktrees/bla/HEAD */ + REF_WORKTREE_SHARED, /* the default, eg. refs/heads/main */ +}; + +/* + * Parse a `maybe_worktree_ref` as a ref that possibly refers to a worktree ref + * (ie. either REFNAME, main-worktree/REFNAME or worktree/WORKTREE/REFNAME). It + * returns what kind of ref was found, and in case of REF_WORKTREE_OTHER, the + * worktree name is returned in `worktree_name` (pointing into + * `maybe_worktree_ref`) and `worktree_name_length`. The bare refname (the + * refname stripped of prefixes) is returned in `bare_refname`. The + * `worktree_name`, `worktree_name_length` and `bare_refname` arguments may be + * NULL. + */ +enum ref_worktree_type parse_worktree_ref(const char *maybe_worktree_ref, + const char **worktree_name, + int *worktree_name_length, + const char **bare_refname); + +enum expire_reflog_flags { + EXPIRE_REFLOGS_DRY_RUN = 1 << 0, + EXPIRE_REFLOGS_UPDATE_REF = 1 << 1, + EXPIRE_REFLOGS_REWRITE = 1 << 2, +}; + +/* + * The following interface is used for reflog expiration. The caller + * calls reflog_expire(), supplying it with three callback functions, + * of the following types. The callback functions define the + * expiration policy that is desired. + * + * reflog_expiry_prepare_fn -- Called once after the reference is + * locked. Called with the OID of the locked reference. + * + * reflog_expiry_should_prune_fn -- Called once for each entry in the + * existing reflog. It should return true iff that entry should be + * pruned. + * + * reflog_expiry_cleanup_fn -- Called once before the reference is + * unlocked again. + */ +typedef void reflog_expiry_prepare_fn(const char *refname, + const struct object_id *oid, + void *cb_data); +typedef int reflog_expiry_should_prune_fn(struct object_id *ooid, + struct object_id *noid, + const char *email, + timestamp_t timestamp, int tz, + const char *message, void *cb_data); +typedef void reflog_expiry_cleanup_fn(void *cb_data); + +/* + * Expire reflog entries for the specified reference. + * flags is a combination of the constants in + * enum expire_reflog_flags. The three function pointers are described + * above. On success, return zero. + */ +int refs_reflog_expire(struct ref_store *refs, + const char *refname, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data); +int reflog_expire(const char *refname, + unsigned int flags, + reflog_expiry_prepare_fn prepare_fn, + reflog_expiry_should_prune_fn should_prune_fn, + reflog_expiry_cleanup_fn cleanup_fn, + void *policy_cb_data); + +struct ref_store *get_main_ref_store(struct repository *r); + +/** + * Submodules + * ---------- + * + * If you want to iterate the refs of a submodule you first need to add the + * submodules object database. You can do this by a code-snippet like + * this: + * + * const char *path = "path/to/submodule" + * if (add_submodule_odb(path)) + * die("Error submodule '%s' not populated.", path); + * + * `add_submodule_odb()` will return zero on success. If you + * do not do this you will get an error for each ref that it does not point + * to a valid object. + * + * Note: As a side-effect of this you cannot safely assume that all + * objects you lookup are available in superproject. All submodule objects + * will be available the same way as the superprojects objects. + * + * Example: + * -------- + * + * ---- + * static int handle_remote_ref(const char *refname, + * const unsigned char *sha1, int flags, void *cb_data) + * { + * struct strbuf *output = cb_data; + * strbuf_addf(output, "%s\n", refname); + * return 0; + * } + * + */ + +/* + * Return the ref_store instance for the specified submodule. For the + * main repository, use submodule==NULL; such a call cannot fail. For + * a submodule, the submodule must exist and be a nonbare repository, + * otherwise return NULL. If the requested reference store has not yet + * been initialized, initialize it first. + * + * For backwards compatibility, submodule=="" is treated the same as + * submodule==NULL. + */ +struct ref_store *get_submodule_ref_store(const char *submodule); +struct ref_store *get_worktree_ref_store(const struct worktree *wt); + +/* + * Some of the names specified by refs have special meaning to Git. + * Organize these namespaces in a comon 'ref_namespace' array for + * reference from multiple places in the codebase. + */ + +struct ref_namespace_info { + char *ref; + enum decoration_type decoration; + + /* + * If 'exact' is true, then we must match the 'ref' exactly. + * Otherwise, use a prefix match. + * + * 'ref_updated' is for internal use. It represents whether the + * 'ref' value was replaced from its original literal version. + */ + unsigned exact:1, + ref_updated:1; +}; + +enum ref_namespace { + NAMESPACE_HEAD, + NAMESPACE_BRANCHES, + NAMESPACE_TAGS, + NAMESPACE_REMOTE_REFS, + NAMESPACE_STASH, + NAMESPACE_REPLACE, + NAMESPACE_NOTES, + NAMESPACE_PREFETCH, + NAMESPACE_REWRITTEN, + + /* Must be last */ + NAMESPACE__COUNT +}; + +/* See refs.c for the contents of this array. */ +extern struct ref_namespace_info ref_namespace[NAMESPACE__COUNT]; + +/* + * Some ref namespaces can be modified by config values or environment + * variables. Modify a namespace as specified by its ref_namespace key. + */ +void update_ref_namespace(enum ref_namespace namespace, char *ref); + +#endif /* REFS_H */ |