files-backend: replace submodule_allowed check in files_downcast()
files-backend.c is unlearning submodules. Instead of having a specific check for submodules to see what operation is allowed, files backend now takes a set of flags at init. Each operation will check if the required flags is present before performing. For now we have four flags: read, write and odb access. Main ref store has all flags, obviously, while submodule stores are read-only and have access to odb (*). The "main" flag stays because many functions in the backend calls frontend ones without a ref store, so these functions always target the main ref store. Ideally the flag should be gone after ref-store-aware api is in place and used by backends. (*) Submodule code needs for_each_ref. Try take REF_STORE_ODB flag out. At least t3404 would fail. The "have access to odb" in submodule is a bit hacky since we don't know from he whether add_submodule_odb() has been called. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Nguyễn Thái Ngọc Duy committed
Mar 26, 2017 at 09:42 UTC
9e7ec634a130535982e9bc63d65c2fe8c076a662
3 files changed
+73
-37
refs.c
+11
-4
@@ -1416,7 +1416,8 @@ static struct ref_store *lookup_submodule_ref_store(const char *submodule)
1416
* Create, record, and return a ref_store instance for the specified
1417
* gitdir.
1418
*/
1419
-static struct ref_store *ref_store_init(const char *gitdir)
1419
+static struct ref_store *ref_store_init(const char *gitdir,
1420
+ unsigned int flags)
1421
{
1422
const char *be_name = "files";
1423
struct ref_storage_be *be = find_ref_storage_backend(be_name);
@@ -1425,7 +1426,7 @@ static struct ref_store *ref_store_init(const char *gitdir)
1426
if (!be)
1427
die("BUG: reference backend %s is unknown", be_name);
1428
1428
- refs = be->init(gitdir);
1429
+ refs = be->init(gitdir, flags);
1430
return refs;
1431
}
1432
@@ -1434,7 +1435,11 @@ struct ref_store *get_main_ref_store(void)
1435
if (main_ref_store)
1436
return main_ref_store;
1437
1437
- main_ref_store = ref_store_init(get_git_dir());
1438
+ main_ref_store = ref_store_init(get_git_dir(),
1439
+ (REF_STORE_READ |
1440
+ REF_STORE_WRITE |
1441
+ REF_STORE_ODB |
1442
+ REF_STORE_MAIN));
1443
return main_ref_store;
1444
}
1445
@@ -1481,7 +1486,9 @@ struct ref_store *get_ref_store(const char *submodule)
1486
return NULL;
1487
}
1488
1484
- refs = ref_store_init(submodule_sb.buf);
1489
+ /* assume that add_submodule_odb() has been called */
1490
+ refs = ref_store_init(submodule_sb.buf,
1491
+ REF_STORE_READ | REF_STORE_ODB);
1492
register_submodule_ref_store(refs, submodule);
1493
1494
strbuf_release(&submodule_sb);
refs/files-backend.c
+54
-32
@@ -916,6 +916,7 @@ struct packed_ref_cache {
916
*/
917
struct files_ref_store {
918
struct ref_store base;
919
+ unsigned int store_flags;
920
921
char *gitdir;
922
char *gitcommondir;
@@ -976,13 +977,15 @@ static void clear_loose_ref_cache(struct files_ref_store *refs)
977
* Create a new submodule ref cache and add it to the internal
978
* set of caches.
979
*/
979
-static struct ref_store *files_ref_store_create(const char *gitdir)
980
+static struct ref_store *files_ref_store_create(const char *gitdir,
981
+ unsigned int flags)
982
{
983
struct files_ref_store *refs = xcalloc(1, sizeof(*refs));
984
struct ref_store *ref_store = (struct ref_store *)refs;
985
struct strbuf sb = STRBUF_INIT;
986
987
base_ref_store_init(ref_store, &refs_be_files);
988
+ refs->store_flags = flags;
989
990
refs->gitdir = xstrdup(gitdir);
991
get_common_dir_noenv(&sb, gitdir);
@@ -994,24 +997,27 @@ static struct ref_store *files_ref_store_create(const char *gitdir)
997
}
998
999
/*
997
- * Die if refs is for a submodule (i.e., not for the main repository).
998
- * caller is used in any necessary error messages.
1000
+ * Die if refs is not the main ref store. caller is used in any
1001
+ * necessary error messages.
1002
*/
1003
static void files_assert_main_repository(struct files_ref_store *refs,
1004
const char *caller)
1005
{
1003
- /* This function is to be fixed up in the next patch */
1006
+ if (refs->store_flags & REF_STORE_MAIN)
1007
+ return;
1008
+
1009
+ die("BUG: operation %s only allowed for main ref store", caller);
1010
}
1011
1012
/*
1013
* Downcast ref_store to files_ref_store. Die if ref_store is not a
1008
- * files_ref_store. If submodule_allowed is not true, then also die if
1009
- * files_ref_store is for a submodule (i.e., not for the main
1010
- * repository). caller is used in any necessary error messages.
1014
+ * files_ref_store. required_flags is compared with ref_store's
1015
+ * store_flags to ensure the ref_store has all required capabilities.
1016
+ * "caller" is used in any necessary error messages.
1017
*/
1012
-static struct files_ref_store *files_downcast(
1013
- struct ref_store *ref_store, int submodule_allowed,
1014
- const char *caller)
1018
+static struct files_ref_store *files_downcast(struct ref_store *ref_store,
1019
+ unsigned int required_flags,
1020
+ const char *caller)
1021
{
1022
struct files_ref_store *refs;
1023
@@ -1021,8 +1027,9 @@ static struct files_ref_store *files_downcast(
1027
1028
refs = (struct files_ref_store *)ref_store;
1029
1024
- if (!submodule_allowed)
1025
- files_assert_main_repository(refs, caller);
1030
+ if ((refs->store_flags & required_flags) != required_flags)
1031
+ die("BUG: operation %s requires abilities 0x%x, but only have 0x%x",
1032
+ caller, required_flags, refs->store_flags);
1033
1034
return refs;
1035
}
@@ -1398,7 +1405,7 @@ static int files_read_raw_ref(struct ref_store *ref_store,
1405
struct strbuf *referent, unsigned int *type)
1406
{
1407
struct files_ref_store *refs =
1401
- files_downcast(ref_store, 1, "read_raw_ref");
1408
+ files_downcast(ref_store, REF_STORE_READ, "read_raw_ref");
1409
struct strbuf sb_contents = STRBUF_INIT;
1410
struct strbuf sb_path = STRBUF_INIT;
1411
const char *path;
@@ -1815,10 +1822,14 @@ static enum peel_status peel_entry(struct ref_entry *entry, int repeel)
1822
static int files_peel_ref(struct ref_store *ref_store,
1823
const char *refname, unsigned char *sha1)
1824
{
1818
- struct files_ref_store *refs = files_downcast(ref_store, 0, "peel_ref");
1825
+ struct files_ref_store *refs =
1826
+ files_downcast(ref_store, REF_STORE_READ | REF_STORE_ODB,
1827
+ "peel_ref");
1828
int flag;
1829
unsigned char base[20];
1830
1831
+ files_assert_main_repository(refs, "peel_ref");
1832
+
1833
if (current_ref_iter && current_ref_iter->refname == refname) {
1834
struct object_id peeled;
1835
@@ -1923,8 +1934,7 @@ static struct ref_iterator *files_ref_iterator_begin(
1934
struct ref_store *ref_store,
1935
const char *prefix, unsigned int flags)
1936
{
1926
- struct files_ref_store *refs =
1927
- files_downcast(ref_store, 1, "ref_iterator_begin");
1937
+ struct files_ref_store *refs;
1938
struct ref_dir *loose_dir, *packed_dir;
1939
struct ref_iterator *loose_iter, *packed_iter;
1940
struct files_ref_iterator *iter;
@@ -1935,6 +1945,10 @@ static struct ref_iterator *files_ref_iterator_begin(
1945
if (ref_paranoia)
1946
flags |= DO_FOR_EACH_INCLUDE_BROKEN;
1947
1948
+ refs = files_downcast(ref_store,
1949
+ REF_STORE_READ | (ref_paranoia ? 0 : REF_STORE_ODB),
1950
+ "ref_iterator_begin");
1951
+
1952
iter = xcalloc(1, sizeof(*iter));
1953
ref_iterator = &iter->base;
1954
base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable);
@@ -2415,7 +2429,8 @@ static void prune_refs(struct ref_to_prune *r)
2429
static int files_pack_refs(struct ref_store *ref_store, unsigned int flags)
2430
{
2431
struct files_ref_store *refs =
2418
- files_downcast(ref_store, 0, "pack_refs");
2432
+ files_downcast(ref_store, REF_STORE_WRITE | REF_STORE_ODB,
2433
+ "pack_refs");
2434
struct pack_refs_cb_data cbdata;
2435
2436
memset(&cbdata, 0, sizeof(cbdata));
@@ -2494,7 +2509,7 @@ static int files_delete_refs(struct ref_store *ref_store,
2509
struct string_list *refnames, unsigned int flags)
2510
{
2511
struct files_ref_store *refs =
2497
- files_downcast(ref_store, 0, "delete_refs");
2512
+ files_downcast(ref_store, REF_STORE_WRITE, "delete_refs");
2513
struct strbuf err = STRBUF_INIT;
2514
int i, result = 0;
2515
@@ -2598,7 +2613,7 @@ static int files_verify_refname_available(struct ref_store *ref_store,
2613
struct strbuf *err)
2614
{
2615
struct files_ref_store *refs =
2601
- files_downcast(ref_store, 1, "verify_refname_available");
2616
+ files_downcast(ref_store, REF_STORE_READ, "verify_refname_available");
2617
struct ref_dir *packed_refs = get_packed_refs(refs);
2618
struct ref_dir *loose_refs = get_loose_refs(refs);
2619
@@ -2623,7 +2638,7 @@ static int files_rename_ref(struct ref_store *ref_store,
2638
const char *logmsg)
2639
{
2640
struct files_ref_store *refs =
2626
- files_downcast(ref_store, 0, "rename_ref");
2641
+ files_downcast(ref_store, REF_STORE_WRITE, "rename_ref");
2642
unsigned char sha1[20], orig_sha1[20];
2643
int flag = 0, logmoved = 0;
2644
struct ref_lock *lock;
@@ -2873,7 +2888,7 @@ static int files_create_reflog(struct ref_store *ref_store,
2888
struct strbuf *err)
2889
{
2890
struct files_ref_store *refs =
2876
- files_downcast(ref_store, 0, "create_reflog");
2891
+ files_downcast(ref_store, REF_STORE_WRITE, "create_reflog");
2892
int fd;
2893
2894
if (log_ref_setup(refs, refname, force_create, &fd, err))
@@ -3117,7 +3132,7 @@ static int files_create_symref(struct ref_store *ref_store,
3132
const char *logmsg)
3133
{
3134
struct files_ref_store *refs =
3120
- files_downcast(ref_store, 0, "create_symref");
3135
+ files_downcast(ref_store, REF_STORE_WRITE, "create_symref");
3136
struct strbuf err = STRBUF_INIT;
3137
struct ref_lock *lock;
3138
int ret;
@@ -3143,7 +3158,9 @@ int set_worktree_head_symref(const char *gitdir, const char *target, const char
3158
* backends. This function needs to die.
3159
*/
3160
struct files_ref_store *refs =
3146
- files_downcast(get_main_ref_store(), 0, "set_head_symref");
3161
+ files_downcast(get_main_ref_store(),
3162
+ REF_STORE_WRITE,
3163
+ "set_head_symref");
3164
3165
static struct lock_file head_lock;
3166
struct ref_lock *lock;
@@ -3182,7 +3199,7 @@ static int files_reflog_exists(struct ref_store *ref_store,
3199
const char *refname)
3200
{
3201
struct files_ref_store *refs =
3185
- files_downcast(ref_store, 0, "reflog_exists");
3202
+ files_downcast(ref_store, REF_STORE_READ, "reflog_exists");
3203
struct strbuf sb = STRBUF_INIT;
3204
struct stat st;
3205
int ret;
@@ -3197,7 +3214,7 @@ static int files_delete_reflog(struct ref_store *ref_store,
3214
const char *refname)
3215
{
3216
struct files_ref_store *refs =
3200
- files_downcast(ref_store, 0, "delete_reflog");
3217
+ files_downcast(ref_store, REF_STORE_WRITE, "delete_reflog");
3218
struct strbuf sb = STRBUF_INIT;
3219
int ret;
3220
@@ -3253,7 +3270,8 @@ static int files_for_each_reflog_ent_reverse(struct ref_store *ref_store,
3270
void *cb_data)
3271
{
3272
struct files_ref_store *refs =
3256
- files_downcast(ref_store, 0, "for_each_reflog_ent_reverse");
3273
+ files_downcast(ref_store, REF_STORE_READ,
3274
+ "for_each_reflog_ent_reverse");
3275
struct strbuf sb = STRBUF_INIT;
3276
FILE *logfp;
3277
long pos;
@@ -3361,7 +3379,8 @@ static int files_for_each_reflog_ent(struct ref_store *ref_store,
3379
each_reflog_ent_fn fn, void *cb_data)
3380
{
3381
struct files_ref_store *refs =
3364
- files_downcast(ref_store, 0, "for_each_reflog_ent");
3382
+ files_downcast(ref_store, REF_STORE_READ,
3383
+ "for_each_reflog_ent");
3384
FILE *logfp;
3385
struct strbuf sb = STRBUF_INIT;
3386
int ret = 0;
@@ -3449,7 +3468,8 @@ static struct ref_iterator_vtable files_reflog_iterator_vtable = {
3468
static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_store)
3469
{
3470
struct files_ref_store *refs =
3452
- files_downcast(ref_store, 0, "reflog_iterator_begin");
3471
+ files_downcast(ref_store, REF_STORE_READ,
3472
+ "reflog_iterator_begin");
3473
struct files_reflog_iterator *iter = xcalloc(1, sizeof(*iter));
3474
struct ref_iterator *ref_iterator = &iter->base;
3475
struct strbuf sb = STRBUF_INIT;
@@ -3787,7 +3807,8 @@ static int files_transaction_commit(struct ref_store *ref_store,
3807
struct strbuf *err)
3808
{
3809
struct files_ref_store *refs =
3790
- files_downcast(ref_store, 0, "ref_transaction_commit");
3810
+ files_downcast(ref_store, REF_STORE_WRITE,
3811
+ "ref_transaction_commit");
3812
int ret = 0, i;
3813
struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;
3814
struct string_list_item *ref_to_delete;
@@ -3992,7 +4013,8 @@ static int files_initial_transaction_commit(struct ref_store *ref_store,
4013
struct strbuf *err)
4014
{
4015
struct files_ref_store *refs =
3995
- files_downcast(ref_store, 0, "initial_ref_transaction_commit");
4016
+ files_downcast(ref_store, REF_STORE_WRITE,
4017
+ "initial_ref_transaction_commit");
4018
int ret = 0, i;
4019
struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
4020
@@ -4114,7 +4136,7 @@ static int files_reflog_expire(struct ref_store *ref_store,
4136
void *policy_cb_data)
4137
{
4138
struct files_ref_store *refs =
4117
- files_downcast(ref_store, 0, "reflog_expire");
4139
+ files_downcast(ref_store, REF_STORE_WRITE, "reflog_expire");
4140
static struct lock_file reflog_lock;
4141
struct expire_reflog_cb cb;
4142
struct ref_lock *lock;
@@ -4220,7 +4242,7 @@ static int files_reflog_expire(struct ref_store *ref_store,
4242
static int files_init_db(struct ref_store *ref_store, struct strbuf *err)
4243
{
4244
struct files_ref_store *refs =
4223
- files_downcast(ref_store, 0, "init_db");
4245
+ files_downcast(ref_store, REF_STORE_WRITE, "init_db");
4246
struct strbuf sb = STRBUF_INIT;
4247
4248
/*
refs/refs-internal.h
+8
-1
@@ -481,12 +481,19 @@ struct ref_store;
481
482
/* refs backends */
483
484
+/* ref_store_init flags */
485
+#define REF_STORE_READ (1 << 0)
486
+#define REF_STORE_WRITE (1 << 1) /* can perform update operations */
487
+#define REF_STORE_ODB (1 << 2) /* has access to object database */
488
+#define REF_STORE_MAIN (1 << 3)
489
+
490
/*
491
* Initialize the ref_store for the specified gitdir. These functions
492
* should call base_ref_store_init() to initialize the shared part of
493
* the ref_store and to record the ref_store for later lookup.
494
*/
489
-typedef struct ref_store *ref_store_init_fn(const char *gitdir);
495
+typedef struct ref_store *ref_store_init_fn(const char *gitdir,
496
+ unsigned int flags);
497
498
typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
499