projects / thirdparty / git.git / blame
| Commit | Line | Data |
|---|---|---|
| 1ae2b8cd HWN |
1 | /* |
| 2 | Copyright 2020 Google LLC | |
| 3 | ||
| 4 | Use of this source code is governed by a BSD-style | |
| 5 | license that can be found in the LICENSE file or at | |
| 6 | https://developers.google.com/open-source/licenses/bsd | |
| 7 | */ | |
| 8 | ||
| 9 | #ifndef REFTABLE_MERGED_H | |
| 10 | #define REFTABLE_MERGED_H | |
| 11 | ||
| 12 | #include "reftable-iterator.h" | |
| 13 | ||
| 14 | /* | |
| 15 | * Merged tables | |
| 16 | * | |
| 17 | * A ref database kept in a sequence of table files. The merged_table presents a | |
| 18 | * unified view to reading (seeking, iterating) a sequence of immutable tables. | |
| 19 | * | |
| 20 | * The merged tables are on purpose kept disconnected from their actual storage | |
| 21 | * (eg. files on disk), because it is useful to merge tables aren't files. For | |
| 22 | * example, the per-workspace and global ref namespace can be implemented as a | |
| 23 | * merged table of two stacks of file-backed reftables. | |
| 24 | */ | |
| 25 | ||
| 26 | /* A merged table is implements seeking/iterating over a stack of tables. */ | |
| 27 | struct reftable_merged_table; | |
| 28 | ||
| 29 | /* A generic reftable; see below. */ | |
| 30 | struct reftable_table; | |
| 31 | ||
| 32 | /* reftable_new_merged_table creates a new merged table. It takes ownership of | |
| 33 | the stack array. | |
| 34 | */ | |
| 35 | int reftable_new_merged_table(struct reftable_merged_table **dest, | |
| 81879123 | 36 | struct reftable_table *stack, size_t n, |
| 1ae2b8cd HWN |
37 | uint32_t hash_id); |
| 38 | ||
| 39 | /* returns an iterator positioned just before 'name' */ | |
| 40 | int reftable_merged_table_seek_ref(struct reftable_merged_table *mt, | |
| 41 | struct reftable_iterator *it, | |
| 42 | const char *name); | |
| 43 | ||
| 44 | /* returns an iterator for log entry, at given update_index */ | |
| 45 | int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt, | |
| 46 | struct reftable_iterator *it, | |
| 47 | const char *name, uint64_t update_index); | |
| 48 | ||
| 49 | /* like reftable_merged_table_seek_log_at but look for the newest entry. */ | |
| 50 | int reftable_merged_table_seek_log(struct reftable_merged_table *mt, | |
| 51 | struct reftable_iterator *it, | |
| 52 | const char *name); | |
| 53 | ||
| 54 | /* returns the max update_index covered by this merged table. */ | |
| 55 | uint64_t | |
| 56 | reftable_merged_table_max_update_index(struct reftable_merged_table *mt); | |
| 57 | ||
| 58 | /* returns the min update_index covered by this merged table. */ | |
| 59 | uint64_t | |
| 60 | reftable_merged_table_min_update_index(struct reftable_merged_table *mt); | |
| 61 | ||
| 62 | /* releases memory for the merged_table */ | |
| 63 | void reftable_merged_table_free(struct reftable_merged_table *m); | |
| 64 | ||
| 65 | /* return the hash ID of the merged table. */ | |
| 66 | uint32_t reftable_merged_table_hash_id(struct reftable_merged_table *m); | |
| 67 | ||
| 68 | /* create a generic table from reftable_merged_table */ | |
| 69 | void reftable_table_from_merged_table(struct reftable_table *tab, | |
| 70 | struct reftable_merged_table *table); | |
| 71 | ||
| 72 | #endif |