global/git
1
0
Fork 0
mirror of https://github.com/git/git.git synced 2026-01-10 01:56:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

reftable: make reftable_record a tagged union

Browse Source 
This reduces the amount of glue code, because we don't need a void
pointer or vtable within the structure.

The only snag is that reftable_index_record contain a strbuf, so it
cannot be zero-initialized. To address this, use reftable_new_record()
to return fresh instance, given a record type. Since
reftable_new_record() doesn't cause heap allocation anymore, it should
be balanced with reftable_record_release() rather than
reftable_record_destroy().

Thanks to Peff for the suggestion.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Han-Wen Nienhuys
2022-01-20 15:12:13 +00:00
committed by Junio C Hamano
parent 9391b88dab
commit 66c0dabab5
12 changed files with 334 additions and 337 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
reftable/record.h
View File

@@ -63,16 +63,10 @@ struct reftable_record_vtable {
int (*equal)(const void *a, const void *b, int hash_size);
};
/* record is a generic wrapper for different types of records. */
struct reftable_record {
void *data;
struct reftable_record_vtable *ops;
};
/* returns true for recognized block types. Block start with the block type. */
int reftable_is_block_type(uint8_t typ);
/* creates a malloced record of the given type. Dispose with record_destroy */
/* return an initialized record for the given type */
struct reftable_record reftable_new_record(uint8_t typ);
/* Encode `key` into `dest`. Sets `is_restart` to indicate a restart. Returns
@@ -100,6 +94,22 @@ struct reftable_obj_record {
int offset_len;
};
/* record is a generic wrapper for different types of records. It is normally
* created on the stack, or embedded within another struct. If the type is
* known, a fresh instance can be initialized explicitly. Otherwise, use
* reftable_new_record() to initialize generically (as the index_record is not
* valid as 0-initialized structure)
*/
struct reftable_record {
uint8_t type;
union {
struct reftable_ref_record ref;
struct reftable_log_record log;
struct reftable_obj_record obj;
struct reftable_index_record idx;
} u;
};
/* see struct record_vtable */
int reftable_record_equal(struct reftable_record *a, struct reftable_record *b, int hash_size);
void reftable_record_key(struct reftable_record *rec, struct strbuf *dest);
@@ -114,25 +124,9 @@ int reftable_record_decode(struct reftable_record *rec, struct strbuf key,
int hash_size);
int reftable_record_is_deletion(struct reftable_record *rec);
/* zeroes out the embedded record */
/* frees and zeroes out the embedded record */
void reftable_record_release(struct reftable_record *rec);
/* clear and deallocate embedded record, and zero `rec`. */
void reftable_record_destroy(struct reftable_record *rec);
/* initialize generic records from concrete records. The generic record should
* be zeroed out. */
void reftable_record_from_obj(struct reftable_record *rec,
struct reftable_obj_record *objrec);
void reftable_record_from_index(struct reftable_record *rec,
struct reftable_index_record *idxrec);
void reftable_record_from_ref(struct reftable_record *rec,
struct reftable_ref_record *refrec);
void reftable_record_from_log(struct reftable_record *rec,
struct reftable_log_record *logrec);
struct reftable_ref_record *reftable_record_as_ref(struct reftable_record *ref);
struct reftable_log_record *reftable_record_as_log(struct reftable_record *ref);
/* for qsort. */
int reftable_ref_record_compare_name(const void *a, const void *b);