diff options
Diffstat (limited to 'refs.h')
| -rw-r--r-- | refs.h | 122 |
1 files changed, 86 insertions, 36 deletions
@@ -10,6 +10,38 @@ struct ref_lock { int force_write; }; +/* + * A ref_transaction represents a collection of ref updates + * that should succeed or fail together. + * + * Calling sequence + * ---------------- + * - Allocate and initialize a `struct ref_transaction` by calling + * `ref_transaction_begin()`. + * + * - List intended ref updates by calling functions like + * `ref_transaction_update()` and `ref_transaction_create()`. + * + * - Call `ref_transaction_commit()` to execute the transaction. + * If this succeeds, the ref updates will have taken place and + * the transaction cannot be rolled back. + * + * - At any time call `ref_transaction_free()` to discard the + * transaction and free associated resources. In particular, + * this rolls back the transaction if it has not been + * successfully committed. + * + * 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. + */ struct ref_transaction; /* @@ -24,12 +56,20 @@ struct ref_transaction; /* * Reference cannot be resolved to an object name: dangling symbolic - * reference (directly or indirectly), corrupt reference file, or - * symbolic reference refers to ill-formatted reference name. + * 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 sha1 * arguments is only guaranteed to be valid for the duration of a @@ -77,7 +117,7 @@ static inline const char *has_glob_specials(const char *pattern) extern int for_each_rawref(each_ref_fn, void *); extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname); -extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list* refnames); +extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames); /* * Lock the packed-refs file for writing. Flags is passed to @@ -141,14 +181,19 @@ extern int is_branch(const char *refname); extern int peel_ref(const char *refname, unsigned char *sha1); /* - * Locks a "refs/" ref returning the lock on success and NULL on failure. - * On failure errno is set to something meaningful. + * Flags controlling lock_any_ref_for_update(), ref_transaction_update(), + * ref_transaction_create(), etc. + * REF_NODEREF: act on the ref directly, instead of dereferencing + * symbolic references. + * REF_DELETING: tolerate broken refs + * + * Flags >= 0x100 are reserved for internal use. */ -extern struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1); - -/** Locks any ref (for 'HEAD' type refs). */ #define REF_NODEREF 0x01 -/* errno is set to something meaningful on failure */ +#define REF_DELETING 0x02 +/* + * This function sets errno to something meaningful on failure. + */ extern struct ref_lock *lock_any_ref_for_update(const char *refname, const unsigned char *old_sha1, int flags, int *type_p); @@ -162,16 +207,14 @@ extern int commit_ref(struct ref_lock *lock); /** Release any lock taken but not written. **/ extern void unlock_ref(struct ref_lock *lock); -/** Writes sha1 into the ref specified by the lock. **/ -extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg); - /* * Setup reflog before using. Set errno to something meaningful on failure. */ int log_ref_setup(const char *refname, char *logfile, int bufsize); /** Reads log for the value of ref during at_time. **/ -extern int read_ref_at(const char *refname, unsigned long at_time, int cnt, +extern int read_ref_at(const char *refname, unsigned int flags, + unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt); @@ -194,7 +237,6 @@ extern int for_each_reflog(each_ref_fn, void *); #define REFNAME_ALLOW_ONELEVEL 1 #define REFNAME_REFSPEC_PATTERN 2 -#define REFNAME_DOT_COMPONENT 4 /* * Return 0 iff refname has the correct format for a refname according @@ -202,10 +244,7 @@ extern int for_each_reflog(each_ref_fn, void *); * 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 "*" wildcard character in place of one of the name - * components. No leading or repeated slashes are accepted. If - * REFNAME_DOT_COMPONENT is set in flags, then allow refname - * components to start with "." (but not a whole component equal to - * "." or ".."). + * components. No leading or repeated slashes are accepted. */ extern int check_refname_format(const char *refname, int flags); @@ -232,14 +271,14 @@ enum action_on_err { * Begin a reference transaction. The reference transaction must * be freed by calling ref_transaction_free(). */ -struct ref_transaction *ref_transaction_begin(void); +struct ref_transaction *ref_transaction_begin(struct strbuf *err); /* * The following functions add a reference check or update to a * ref_transaction. In all of them, refname is the name of the * reference to be affected. The functions make internal copies of - * refname, so the caller retains ownership of the parameter. flags - * can be REF_NODEREF; it is passed to update_ref_lock(). + * refname and msg, so the caller retains ownership of these parameters. + * flags can be REF_NODEREF; it is passed to update_ref_lock(). */ /* @@ -250,13 +289,13 @@ struct ref_transaction *ref_transaction_begin(void); * it must not have existed beforehand. * Function returns 0 on success and non-zero on failure. A failure to update * means that the transaction as a whole has failed and will need to be - * rolled back. On failure the err buffer will be updated. + * rolled back. */ int ref_transaction_update(struct ref_transaction *transaction, const char *refname, const unsigned char *new_sha1, const unsigned char *old_sha1, - int flags, int have_old, + int flags, int have_old, const char *msg, struct strbuf *err); /* @@ -264,31 +303,42 @@ int ref_transaction_update(struct ref_transaction *transaction, * that the reference should have after the update; it must not be the * null SHA-1. It is verified that the reference does not exist * already. + * Function returns 0 on success and non-zero on failure. A failure to create + * means that the transaction as a whole has failed and will need to be + * rolled back. */ -void ref_transaction_create(struct ref_transaction *transaction, - const char *refname, - const unsigned char *new_sha1, - int flags); +int ref_transaction_create(struct ref_transaction *transaction, + const char *refname, + const unsigned char *new_sha1, + int flags, const char *msg, + struct strbuf *err); /* * Add a reference deletion to transaction. If have_old is true, then * old_sha1 holds the value that the reference should have had before * the update (which must not be the null SHA-1). + * Function returns 0 on success and non-zero on failure. A failure to delete + * means that the transaction as a whole has failed and will need to be + * rolled back. */ -void ref_transaction_delete(struct ref_transaction *transaction, - const char *refname, - const unsigned char *old_sha1, - int flags, int have_old); +int ref_transaction_delete(struct ref_transaction *transaction, + const char *refname, + const unsigned char *old_sha1, + int flags, int have_old, const char *msg, + struct strbuf *err); /* * Commit all of the changes that have been queued in transaction, as - * atomically as possible. Return a nonzero value if there is a - * problem. - * If err is non-NULL we will add an error string to it to explain why - * the transaction failed. The string does not end in newline. + * atomically as possible. + * + * Returns 0 for success, or one of the below error codes for errors. */ +/* 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 int ref_transaction_commit(struct ref_transaction *transaction, - const char *msg, struct strbuf *err); + struct strbuf *err); /* * Free an existing transaction and all associated data. |