Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * dummy_index_am.c
       4             :  *      Index AM template main file.
       5             :  *
       6             :  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
       7             :  * Portions Copyright (c) 1994, Regents of the University of California
       8             :  *
       9             :  * IDENTIFICATION
      10             :  *    src/test/modules/dummy_index_am/dummy_index_am.c
      11             :  *
      12             :  *-------------------------------------------------------------------------
      13             :  */
      14             : #include "postgres.h"
      15             : 
      16             : #include "access/amapi.h"
      17             : #include "access/reloptions.h"
      18             : #include "catalog/index.h"
      19             : #include "commands/vacuum.h"
      20             : #include "nodes/pathnodes.h"
      21             : #include "utils/guc.h"
      22             : #include "utils/rel.h"
      23             : 
      24           2 : PG_MODULE_MAGIC;
      25             : 
      26             : /* parse table for fillRelOptions */
      27             : relopt_parse_elt di_relopt_tab[6];
      28             : 
      29             : /* Kind of relation options for dummy index */
      30             : relopt_kind di_relopt_kind;
      31             : 
      32             : typedef enum DummyAmEnum
      33             : {
      34             :     DUMMY_AM_ENUM_ONE,
      35             :     DUMMY_AM_ENUM_TWO,
      36             : }           DummyAmEnum;
      37             : 
      38             : /* Dummy index options */
      39             : typedef struct DummyIndexOptions
      40             : {
      41             :     int32       vl_len_;        /* varlena header (do not touch directly!) */
      42             :     int         option_int;
      43             :     double      option_real;
      44             :     bool        option_bool;
      45             :     DummyAmEnum option_enum;
      46             :     int         option_string_val_offset;
      47             :     int         option_string_null_offset;
      48             : }           DummyIndexOptions;
      49             : 
      50             : relopt_enum_elt_def dummyAmEnumValues[] =
      51             : {
      52             :     {"one", DUMMY_AM_ENUM_ONE},
      53             :     {"two", DUMMY_AM_ENUM_TWO},
      54             :     {(const char *) NULL}       /* list terminator */
      55             : };
      56             : 
      57             : /* Handler for index AM */
      58           4 : PG_FUNCTION_INFO_V1(dihandler);
      59             : 
      60             : /*
      61             :  * Validation function for string relation options.
      62             :  */
      63             : static void
      64          60 : validate_string_option(const char *value)
      65             : {
      66          60 :     ereport(NOTICE,
      67             :             (errmsg("new option value for string parameter %s",
      68             :                     value ? value : "NULL")));
      69          60 : }
      70             : 
      71             : /*
      72             :  * This function creates a full set of relation option types,
      73             :  * with various patterns.
      74             :  */
      75             : static void
      76           2 : create_reloptions_table(void)
      77             : {
      78           2 :     di_relopt_kind = add_reloption_kind();
      79             : 
      80           2 :     add_int_reloption(di_relopt_kind, "option_int",
      81             :                       "Integer option for dummy_index_am",
      82             :                       10, -10, 100, AccessExclusiveLock);
      83           2 :     di_relopt_tab[0].optname = "option_int";
      84           2 :     di_relopt_tab[0].opttype = RELOPT_TYPE_INT;
      85           2 :     di_relopt_tab[0].offset = offsetof(DummyIndexOptions, option_int);
      86             : 
      87           2 :     add_real_reloption(di_relopt_kind, "option_real",
      88             :                        "Real option for dummy_index_am",
      89             :                        3.1415, -10, 100, AccessExclusiveLock);
      90           2 :     di_relopt_tab[1].optname = "option_real";
      91           2 :     di_relopt_tab[1].opttype = RELOPT_TYPE_REAL;
      92           2 :     di_relopt_tab[1].offset = offsetof(DummyIndexOptions, option_real);
      93             : 
      94           2 :     add_bool_reloption(di_relopt_kind, "option_bool",
      95             :                        "Boolean option for dummy_index_am",
      96             :                        true, AccessExclusiveLock);
      97           2 :     di_relopt_tab[2].optname = "option_bool";
      98           2 :     di_relopt_tab[2].opttype = RELOPT_TYPE_BOOL;
      99           2 :     di_relopt_tab[2].offset = offsetof(DummyIndexOptions, option_bool);
     100             : 
     101           2 :     add_enum_reloption(di_relopt_kind, "option_enum",
     102             :                        "Enum option for dummy_index_am",
     103             :                        dummyAmEnumValues,
     104             :                        DUMMY_AM_ENUM_ONE,
     105             :                        "Valid values are \"one\" and \"two\".",
     106             :                        AccessExclusiveLock);
     107           2 :     di_relopt_tab[3].optname = "option_enum";
     108           2 :     di_relopt_tab[3].opttype = RELOPT_TYPE_ENUM;
     109           2 :     di_relopt_tab[3].offset = offsetof(DummyIndexOptions, option_enum);
     110             : 
     111           2 :     add_string_reloption(di_relopt_kind, "option_string_val",
     112             :                          "String option for dummy_index_am with non-NULL default",
     113             :                          "DefaultValue", &validate_string_option,
     114             :                          AccessExclusiveLock);
     115           2 :     di_relopt_tab[4].optname = "option_string_val";
     116           2 :     di_relopt_tab[4].opttype = RELOPT_TYPE_STRING;
     117           2 :     di_relopt_tab[4].offset = offsetof(DummyIndexOptions,
     118             :                                        option_string_val_offset);
     119             : 
     120             :     /*
     121             :      * String option for dummy_index_am with NULL default, and without
     122             :      * description.
     123             :      */
     124           2 :     add_string_reloption(di_relopt_kind, "option_string_null",
     125             :                          NULL,  /* description */
     126             :                          NULL, &validate_string_option,
     127             :                          AccessExclusiveLock);
     128           2 :     di_relopt_tab[5].optname = "option_string_null";
     129           2 :     di_relopt_tab[5].opttype = RELOPT_TYPE_STRING;
     130           2 :     di_relopt_tab[5].offset = offsetof(DummyIndexOptions,
     131             :                                        option_string_null_offset);
     132           2 : }
     133             : 
     134             : 
     135             : /*
     136             :  * Build a new index.
     137             :  */
     138             : static IndexBuildResult *
     139           4 : dibuild(Relation heap, Relation index, IndexInfo *indexInfo)
     140             : {
     141             :     IndexBuildResult *result;
     142             : 
     143           4 :     result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
     144             : 
     145             :     /* let's pretend that no tuples were scanned */
     146           4 :     result->heap_tuples = 0;
     147             :     /* and no index tuples were created (that is true) */
     148           4 :     result->index_tuples = 0;
     149             : 
     150           4 :     return result;
     151             : }
     152             : 
     153             : /*
     154             :  * Build an empty index for the initialization fork.
     155             :  */
     156             : static void
     157           0 : dibuildempty(Relation index)
     158             : {
     159             :     /* No need to build an init fork for a dummy index */
     160           0 : }
     161             : 
     162             : /*
     163             :  * Insert new tuple to index AM.
     164             :  */
     165             : static bool
     166           0 : diinsert(Relation index, Datum *values, bool *isnull,
     167             :          ItemPointer ht_ctid, Relation heapRel,
     168             :          IndexUniqueCheck checkUnique,
     169             :          bool indexUnchanged,
     170             :          IndexInfo *indexInfo)
     171             : {
     172             :     /* nothing to do */
     173           0 :     return false;
     174             : }
     175             : 
     176             : /*
     177             :  * Bulk deletion of all index entries pointing to a set of table tuples.
     178             :  */
     179             : static IndexBulkDeleteResult *
     180           0 : dibulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
     181             :              IndexBulkDeleteCallback callback, void *callback_state)
     182             : {
     183             :     /*
     184             :      * There is nothing to delete.  Return NULL as there is nothing to pass to
     185             :      * amvacuumcleanup.
     186             :      */
     187           0 :     return NULL;
     188             : }
     189             : 
     190             : /*
     191             :  * Post-VACUUM cleanup for index AM.
     192             :  */
     193             : static IndexBulkDeleteResult *
     194           0 : divacuumcleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
     195             : {
     196             :     /* Index has not been modified, so returning NULL is fine */
     197           0 :     return NULL;
     198             : }
     199             : 
     200             : /*
     201             :  * Estimate cost of index AM.
     202             :  */
     203             : static void
     204           0 : dicostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
     205             :                Cost *indexStartupCost, Cost *indexTotalCost,
     206             :                Selectivity *indexSelectivity, double *indexCorrelation,
     207             :                double *indexPages)
     208             : {
     209             :     /* Tell planner to never use this index! */
     210           0 :     *indexStartupCost = 1.0e10;
     211           0 :     *indexTotalCost = 1.0e10;
     212             : 
     213             :     /* Do not care about the rest */
     214           0 :     *indexSelectivity = 1;
     215           0 :     *indexCorrelation = 0;
     216           0 :     *indexPages = 1;
     217           0 : }
     218             : 
     219             : /*
     220             :  * Parse relation options for index AM, returning a DummyIndexOptions
     221             :  * structure filled with option values.
     222             :  */
     223             : static bytea *
     224         138 : dioptions(Datum reloptions, bool validate)
     225             : {
     226         138 :     return (bytea *) build_reloptions(reloptions, validate,
     227             :                                       di_relopt_kind,
     228             :                                       sizeof(DummyIndexOptions),
     229             :                                       di_relopt_tab, lengthof(di_relopt_tab));
     230             : }
     231             : 
     232             : /*
     233             :  * Validator for index AM.
     234             :  */
     235             : static bool
     236           0 : divalidate(Oid opclassoid)
     237             : {
     238             :     /* Index is dummy so we are happy with any opclass */
     239           0 :     return true;
     240             : }
     241             : 
     242             : /*
     243             :  * Begin scan of index AM.
     244             :  */
     245             : static IndexScanDesc
     246           0 : dibeginscan(Relation r, int nkeys, int norderbys)
     247             : {
     248             :     IndexScanDesc scan;
     249             : 
     250             :     /* Let's pretend we are doing something */
     251           0 :     scan = RelationGetIndexScan(r, nkeys, norderbys);
     252           0 :     return scan;
     253             : }
     254             : 
     255             : /*
     256             :  * Rescan of index AM.
     257             :  */
     258             : static void
     259           0 : direscan(IndexScanDesc scan, ScanKey scankey, int nscankeys,
     260             :          ScanKey orderbys, int norderbys)
     261             : {
     262             :     /* nothing to do */
     263           0 : }
     264             : 
     265             : /*
     266             :  * End scan of index AM.
     267             :  */
     268             : static void
     269           0 : diendscan(IndexScanDesc scan)
     270             : {
     271             :     /* nothing to do */
     272           0 : }
     273             : 
     274             : /*
     275             :  * Index AM handler function: returns IndexAmRoutine with access method
     276             :  * parameters and callbacks.
     277             :  */
     278             : Datum
     279          66 : dihandler(PG_FUNCTION_ARGS)
     280             : {
     281          66 :     IndexAmRoutine *amroutine = makeNode(IndexAmRoutine);
     282             : 
     283          66 :     amroutine->amstrategies = 0;
     284          66 :     amroutine->amsupport = 1;
     285          66 :     amroutine->amcanorder = false;
     286          66 :     amroutine->amcanorderbyop = false;
     287          66 :     amroutine->amcanbackward = false;
     288          66 :     amroutine->amcanunique = false;
     289          66 :     amroutine->amcanmulticol = false;
     290          66 :     amroutine->amoptionalkey = false;
     291          66 :     amroutine->amsearcharray = false;
     292          66 :     amroutine->amsearchnulls = false;
     293          66 :     amroutine->amstorage = false;
     294          66 :     amroutine->amclusterable = false;
     295          66 :     amroutine->ampredlocks = false;
     296          66 :     amroutine->amcanparallel = false;
     297          66 :     amroutine->amcanbuildparallel = false;
     298          66 :     amroutine->amcaninclude = false;
     299          66 :     amroutine->amusemaintenanceworkmem = false;
     300          66 :     amroutine->amsummarizing = false;
     301          66 :     amroutine->amparallelvacuumoptions = VACUUM_OPTION_NO_PARALLEL;
     302          66 :     amroutine->amkeytype = InvalidOid;
     303             : 
     304          66 :     amroutine->ambuild = dibuild;
     305          66 :     amroutine->ambuildempty = dibuildempty;
     306          66 :     amroutine->aminsert = diinsert;
     307          66 :     amroutine->ambulkdelete = dibulkdelete;
     308          66 :     amroutine->amvacuumcleanup = divacuumcleanup;
     309          66 :     amroutine->amcanreturn = NULL;
     310          66 :     amroutine->amcostestimate = dicostestimate;
     311          66 :     amroutine->amoptions = dioptions;
     312          66 :     amroutine->amproperty = NULL;
     313          66 :     amroutine->ambuildphasename = NULL;
     314          66 :     amroutine->amvalidate = divalidate;
     315          66 :     amroutine->ambeginscan = dibeginscan;
     316          66 :     amroutine->amrescan = direscan;
     317          66 :     amroutine->amgettuple = NULL;
     318          66 :     amroutine->amgetbitmap = NULL;
     319          66 :     amroutine->amendscan = diendscan;
     320          66 :     amroutine->ammarkpos = NULL;
     321          66 :     amroutine->amrestrpos = NULL;
     322          66 :     amroutine->amestimateparallelscan = NULL;
     323          66 :     amroutine->aminitparallelscan = NULL;
     324          66 :     amroutine->amparallelrescan = NULL;
     325             : 
     326          66 :     PG_RETURN_POINTER(amroutine);
     327             : }
     328             : 
     329             : void
     330           2 : _PG_init(void)
     331             : {
     332           2 :     create_reloptions_table();
     333           2 : }