mirror of
https://github.com/git/git
synced 2024-11-05 18:59:29 +00:00
e48d427268
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
128 lines
4.4 KiB
C
128 lines
4.4 KiB
C
/*
|
|
Copyright 2020 Google LLC
|
|
|
|
Use of this source code is governed by a BSD-style
|
|
license that can be found in the LICENSE file or at
|
|
https://developers.google.com/open-source/licenses/bsd
|
|
*/
|
|
|
|
#ifndef REFTABLE_STACK_H
|
|
#define REFTABLE_STACK_H
|
|
|
|
#include "reftable-writer.h"
|
|
|
|
/*
|
|
* The stack presents an interface to a mutable sequence of reftables.
|
|
|
|
* A stack can be mutated by pushing a table to the top of the stack.
|
|
|
|
* The reftable_stack automatically compacts files on disk to ensure good
|
|
* amortized performance.
|
|
*
|
|
* For windows and other platforms that cannot have open files as rename
|
|
* destinations, concurrent access from multiple processes needs the rand()
|
|
* random seed to be randomized.
|
|
*/
|
|
struct reftable_stack;
|
|
|
|
/* open a new reftable stack. The tables along with the table list will be
|
|
* stored in 'dir'. Typically, this should be .git/reftables.
|
|
*/
|
|
int reftable_new_stack(struct reftable_stack **dest, const char *dir,
|
|
struct reftable_write_options config);
|
|
|
|
/* returns the update_index at which a next table should be written. */
|
|
uint64_t reftable_stack_next_update_index(struct reftable_stack *st);
|
|
|
|
/* holds a transaction to add tables at the top of a stack. */
|
|
struct reftable_addition;
|
|
|
|
/*
|
|
* returns a new transaction to add reftables to the given stack. As a side
|
|
* effect, the ref database is locked.
|
|
*/
|
|
int reftable_stack_new_addition(struct reftable_addition **dest,
|
|
struct reftable_stack *st);
|
|
|
|
/* Adds a reftable to transaction. */
|
|
int reftable_addition_add(struct reftable_addition *add,
|
|
int (*write_table)(struct reftable_writer *wr,
|
|
void *arg),
|
|
void *arg);
|
|
|
|
/* Commits the transaction, releasing the lock. After calling this,
|
|
* reftable_addition_destroy should still be called.
|
|
*/
|
|
int reftable_addition_commit(struct reftable_addition *add);
|
|
|
|
/* Release all non-committed data from the transaction, and deallocate the
|
|
* transaction. Releases the lock if held. */
|
|
void reftable_addition_destroy(struct reftable_addition *add);
|
|
|
|
/* add a new table to the stack. The write_table function must call
|
|
* reftable_writer_set_limits, add refs and return an error value. */
|
|
int reftable_stack_add(struct reftable_stack *st,
|
|
int (*write_table)(struct reftable_writer *wr,
|
|
void *write_arg),
|
|
void *write_arg);
|
|
|
|
/* returns the merged_table for seeking. This table is valid until the
|
|
* next write or reload, and should not be closed or deleted.
|
|
*/
|
|
struct reftable_merged_table *
|
|
reftable_stack_merged_table(struct reftable_stack *st);
|
|
|
|
/* frees all resources associated with the stack. */
|
|
void reftable_stack_destroy(struct reftable_stack *st);
|
|
|
|
/* Reloads the stack if necessary. This is very cheap to run if the stack was up
|
|
* to date */
|
|
int reftable_stack_reload(struct reftable_stack *st);
|
|
|
|
/* Policy for expiring reflog entries. */
|
|
struct reftable_log_expiry_config {
|
|
/* Drop entries older than this timestamp */
|
|
uint64_t time;
|
|
|
|
/* Drop older entries */
|
|
uint64_t min_update_index;
|
|
};
|
|
|
|
/* compacts all reftables into a giant table. Expire reflog entries if config is
|
|
* non-NULL */
|
|
int reftable_stack_compact_all(struct reftable_stack *st,
|
|
struct reftable_log_expiry_config *config);
|
|
|
|
/* heuristically compact unbalanced table stack. */
|
|
int reftable_stack_auto_compact(struct reftable_stack *st);
|
|
|
|
/* delete stale .ref tables. */
|
|
int reftable_stack_clean(struct reftable_stack *st);
|
|
|
|
/* convenience function to read a single ref. Returns < 0 for error, 0 for
|
|
* success, and 1 if ref not found. */
|
|
int reftable_stack_read_ref(struct reftable_stack *st, const char *refname,
|
|
struct reftable_ref_record *ref);
|
|
|
|
/* convenience function to read a single log. Returns < 0 for error, 0 for
|
|
* success, and 1 if ref not found. */
|
|
int reftable_stack_read_log(struct reftable_stack *st, const char *refname,
|
|
struct reftable_log_record *log);
|
|
|
|
/* statistics on past compactions. */
|
|
struct reftable_compaction_stats {
|
|
uint64_t bytes; /* total number of bytes written */
|
|
uint64_t entries_written; /* total number of entries written, including
|
|
failures. */
|
|
int attempts; /* how often we tried to compact */
|
|
int failures; /* failures happen on concurrent updates */
|
|
};
|
|
|
|
/* return statistics for compaction up till now. */
|
|
struct reftable_compaction_stats *
|
|
reftable_stack_compaction_stats(struct reftable_stack *st);
|
|
|
|
/* print the entire stack represented by the directory */
|
|
int reftable_stack_print_directory(const char *stackdir, uint32_t hash_id);
|
|
|
|
#endif
|