Line data    Source code

       1             : /*--------------------------------------------------------------------------
       2             :  *
       3             :  * test_dsm_registry.c
       4             :  *    Test the dynamic shared memory registry.
       5             :  *
       6             :  * Copyright (c) 2024-2025, PostgreSQL Global Development Group
       7             :  *
       8             :  * IDENTIFICATION
       9             :  *      src/test/modules/test_dsm_registry/test_dsm_registry.c
      10             :  *
      11             :  * -------------------------------------------------------------------------
      12             :  */
      13             : #include "postgres.h"
      14             : 
      15             : #include "fmgr.h"
      16             : #include "storage/dsm_registry.h"
      17             : #include "storage/lwlock.h"
      18             : #include "utils/builtins.h"
      19             : 
      20           4 : PG_MODULE_MAGIC;
      21             : 
      22             : typedef struct TestDSMRegistryStruct
      23             : {
      24             :     int         val;
      25             :     LWLock      lck;
      26             : } TestDSMRegistryStruct;
      27             : 
      28             : typedef struct TestDSMRegistryHashEntry
      29             : {
      30             :     char        key[64];
      31             :     dsa_pointer val;
      32             : } TestDSMRegistryHashEntry;
      33             : 
      34             : static TestDSMRegistryStruct *tdr_dsm;
      35             : static dsa_area *tdr_dsa;
      36             : static dshash_table *tdr_hash;
      37             : 
      38             : static const dshash_parameters dsh_params = {
      39             :     offsetof(TestDSMRegistryHashEntry, val),
      40             :     sizeof(TestDSMRegistryHashEntry),
      41             :     dshash_strcmp,
      42             :     dshash_strhash,
      43             :     dshash_strcpy
      44             : };
      45             : 
      46             : static void
      47           2 : init_tdr_dsm(void *ptr)
      48             : {
      49           2 :     TestDSMRegistryStruct *dsm = (TestDSMRegistryStruct *) ptr;
      50             : 
      51           2 :     LWLockInitialize(&dsm->lck, LWLockNewTrancheId());
      52           2 :     dsm->val = 0;
      53           2 : }
      54             : 
      55             : static void
      56           8 : tdr_attach_shmem(void)
      57             : {
      58             :     bool        found;
      59             : 
      60           8 :     tdr_dsm = GetNamedDSMSegment("test_dsm_registry_dsm",
      61             :                                  sizeof(TestDSMRegistryStruct),
      62             :                                  init_tdr_dsm,
      63             :                                  &found);
      64           8 :     LWLockRegisterTranche(tdr_dsm->lck.tranche, "test_dsm_registry");
      65             : 
      66           8 :     if (tdr_dsa == NULL)
      67           4 :         tdr_dsa = GetNamedDSA("test_dsm_registry_dsa", &found);
      68             : 
      69           8 :     if (tdr_hash == NULL)
      70           4 :         tdr_hash = GetNamedDSHash("test_dsm_registry_hash", &dsh_params, &found);
      71           8 : }
      72             : 
      73           4 : PG_FUNCTION_INFO_V1(set_val_in_shmem);
      74             : Datum
      75           2 : set_val_in_shmem(PG_FUNCTION_ARGS)
      76             : {
      77           2 :     tdr_attach_shmem();
      78             : 
      79           2 :     LWLockAcquire(&tdr_dsm->lck, LW_EXCLUSIVE);
      80           2 :     tdr_dsm->val = PG_GETARG_INT32(0);
      81           2 :     LWLockRelease(&tdr_dsm->lck);
      82             : 
      83           2 :     PG_RETURN_VOID();
      84             : }
      85             : 
      86           4 : PG_FUNCTION_INFO_V1(get_val_in_shmem);
      87             : Datum
      88           2 : get_val_in_shmem(PG_FUNCTION_ARGS)
      89             : {
      90             :     int         ret;
      91             : 
      92           2 :     tdr_attach_shmem();
      93             : 
      94           2 :     LWLockAcquire(&tdr_dsm->lck, LW_SHARED);
      95           2 :     ret = tdr_dsm->val;
      96           2 :     LWLockRelease(&tdr_dsm->lck);
      97             : 
      98           2 :     PG_RETURN_INT32(ret);
      99             : }
     100             : 
     101           4 : PG_FUNCTION_INFO_V1(set_val_in_hash);
     102             : Datum
     103           2 : set_val_in_hash(PG_FUNCTION_ARGS)
     104             : {
     105             :     TestDSMRegistryHashEntry *entry;
     106           2 :     char       *key = TextDatumGetCString(PG_GETARG_DATUM(0));
     107           2 :     char       *val = TextDatumGetCString(PG_GETARG_DATUM(1));
     108             :     bool        found;
     109             : 
     110           2 :     if (strlen(key) >= offsetof(TestDSMRegistryHashEntry, val))
     111           0 :         ereport(ERROR,
     112             :                 (errmsg("key too long")));
     113             : 
     114           2 :     tdr_attach_shmem();
     115             : 
     116           2 :     entry = dshash_find_or_insert(tdr_hash, key, &found);
     117           2 :     if (found)
     118           0 :         dsa_free(tdr_dsa, entry->val);
     119             : 
     120           2 :     entry->val = dsa_allocate(tdr_dsa, strlen(val) + 1);
     121           2 :     strcpy(dsa_get_address(tdr_dsa, entry->val), val);
     122             : 
     123           2 :     dshash_release_lock(tdr_hash, entry);
     124             : 
     125           2 :     PG_RETURN_VOID();
     126             : }
     127             : 
     128           4 : PG_FUNCTION_INFO_V1(get_val_in_hash);
     129             : Datum
     130           2 : get_val_in_hash(PG_FUNCTION_ARGS)
     131             : {
     132             :     TestDSMRegistryHashEntry *entry;
     133           2 :     char       *key = TextDatumGetCString(PG_GETARG_DATUM(0));
     134           2 :     text       *val = NULL;
     135             : 
     136           2 :     tdr_attach_shmem();
     137             : 
     138           2 :     entry = dshash_find(tdr_hash, key, false);
     139           2 :     if (entry == NULL)
     140           0 :         PG_RETURN_NULL();
     141             : 
     142           2 :     val = cstring_to_text(dsa_get_address(tdr_dsa, entry->val));
     143             : 
     144           2 :     dshash_release_lock(tdr_hash, entry);
     145             : 
     146           2 :     PG_RETURN_TEXT_P(val);
     147             : }