tid.c File Reference

#include "postgres.h"
#include <math.h>
#include <limits.h>
#include "access/heapam.h"
#include "access/sysattr.h"
#include "access/tableam.h"
#include "catalog/namespace.h"
#include "catalog/pg_type.h"
#include "common/hashfn.h"
#include "libpq/pqformat.h"
#include "miscadmin.h"
#include "parser/parsetree.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"
#include "utils/varlena.h"

Include dependency graph for tid.c:

Go to the source code of this file.

Macros
#define	DatumGetItemPointer(X)   ((ItemPointer) DatumGetPointer(X))
#define	ItemPointerGetDatum(X)   PointerGetDatum(X)
#define	PG_GETARG_ITEMPOINTER(n)   DatumGetItemPointer(PG_GETARG_DATUM(n))
#define	PG_RETURN_ITEMPOINTER(x)   return ItemPointerGetDatum(x)
#define	LDELIM   '('
#define	RDELIM   ')'
#define	DELIM   ','
#define	NTIDARGS   2

Functions
static ItemPointer	currtid_for_view (Relation viewrel, ItemPointer tid)
Datum	tidin (PG_FUNCTION_ARGS)
Datum	tidout (PG_FUNCTION_ARGS)
Datum	tidrecv (PG_FUNCTION_ARGS)
Datum	tidsend (PG_FUNCTION_ARGS)
Datum	tideq (PG_FUNCTION_ARGS)
Datum	tidne (PG_FUNCTION_ARGS)
Datum	tidlt (PG_FUNCTION_ARGS)
Datum	tidle (PG_FUNCTION_ARGS)
Datum	tidgt (PG_FUNCTION_ARGS)
Datum	tidge (PG_FUNCTION_ARGS)
Datum	bttidcmp (PG_FUNCTION_ARGS)
Datum	tidlarger (PG_FUNCTION_ARGS)
Datum	tidsmaller (PG_FUNCTION_ARGS)
Datum	hashtid (PG_FUNCTION_ARGS)
Datum	hashtidextended (PG_FUNCTION_ARGS)
static ItemPointer	currtid_internal (Relation rel, ItemPointer tid)
Datum	currtid_byrelname (PG_FUNCTION_ARGS)

Macro Definition Documentation

DatumGetItemPointer

#define DatumGetItemPointer

(

X

)

((ItemPointer) DatumGetPointer(X))

Definition at line 40 of file tid.c.

DELIM

#define DELIM   ','

Definition at line 47 of file tid.c.

Referenced by tidin().

ItemPointerGetDatum

#define ItemPointerGetDatum

(

X

)

PointerGetDatum(X)

Definition at line 41 of file tid.c.

LDELIM

#define LDELIM   '('

Definition at line 45 of file tid.c.

Referenced by tidin().

NTIDARGS

#define NTIDARGS   2

Definition at line 48 of file tid.c.

Referenced by tidin().

PG_GETARG_ITEMPOINTER

#define PG_GETARG_ITEMPOINTER

(

n

)

DatumGetItemPointer(PG_GETARG_DATUM(n))

Definition at line 42 of file tid.c.

Referenced by bttidcmp(), currtid_byrelname(), hashtid(), hashtidextended(), tideq(), tidge(), tidgt(), tidlarger(), tidle(), tidlt(), tidne(), tidout(), tidsend(), and tidsmaller().

PG_RETURN_ITEMPOINTER

#define PG_RETURN_ITEMPOINTER

(

x

)

return ItemPointerGetDatum(x)

Definition at line 43 of file tid.c.

Referenced by currtid_byrelname(), tidin(), tidlarger(), tidrecv(), and tidsmaller().

RDELIM

#define RDELIM   ')'

Definition at line 46 of file tid.c.

Referenced by tidin().

Function Documentation

bttidcmp()

Datum bttidcmp

(

PG_FUNCTION_ARGS

)

Definition at line 220 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_INT32.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_INT32(ItemPointerCompare(arg1, arg2));
}

currtid_byrelname()

Datum currtid_byrelname

(

PG_FUNCTION_ARGS

)

Definition at line 398 of file tid.c.

References AccessShareLock, currtid_internal(), makeRangeVarFromNameList(), PG_GETARG_ITEMPOINTER, PG_GETARG_TEXT_PP, PG_RETURN_ITEMPOINTER, relname, table_close(), table_openrv(), and textToQualifiedNameList().

{
    text       *relname = PG_GETARG_TEXT_PP(0);
    ItemPointer tid = PG_GETARG_ITEMPOINTER(1);
    ItemPointer result;
    RangeVar   *relrv;
    Relation    rel;

    relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
    rel = table_openrv(relrv, AccessShareLock);

    /* grab the latest tuple version associated to this CTID */
    result = currtid_internal(rel, tid);

    table_close(rel, AccessShareLock);

    PG_RETURN_ITEMPOINTER(result);
}

currtid_for_view()

static ItemPointer currtid_for_view ( Relation  viewrel, ItemPointer  tid  )

static

Definition at line 326 of file tid.c.

References AccessShareLock, RewriteRule::actions, CMD_SELECT, currtid_internal(), elog, ERROR, RewriteRule::event, TargetEntry::expr, get_tle_by_resno(), i, IS_SPECIAL_VARNO, IsA, linitial, list_length(), NameStr, TupleDescData::natts, RuleLock::numLocks, RelationData::rd_rules, RelationGetDescr, rt_fetch, Query::rtable, RuleLock::rules, SelfItemPointerAttributeNumber, table_close(), table_open(), Query::targetList, TupleDescAttr, Var::varattno, and Var::varno.

Referenced by currtid_internal().

{
    TupleDesc   att = RelationGetDescr(viewrel);
    RuleLock   *rulelock;
    RewriteRule *rewrite;
    int         i,
                natts = att->natts,
                tididx = -1;

    for (i = 0; i < natts; i++)
    {
        Form_pg_attribute attr = TupleDescAttr(att, i);

        if (strcmp(NameStr(attr->attname), "ctid") == 0)
        {
            if (attr->atttypid != TIDOID)
                elog(ERROR, "ctid isn't of type TID");
            tididx = i;
            break;
        }
    }
    if (tididx < 0)
        elog(ERROR, "currtid cannot handle views with no CTID");
    rulelock = viewrel->rd_rules;
    if (!rulelock)
        elog(ERROR, "the view has no rules");
    for (i = 0; i < rulelock->numLocks; i++)
    {
        rewrite = rulelock->rules[i];
        if (rewrite->event == CMD_SELECT)
        {
            Query      *query;
            TargetEntry *tle;

            if (list_length(rewrite->actions) != 1)
                elog(ERROR, "only one select rule is allowed in views");
            query = (Query *) linitial(rewrite->actions);
            tle = get_tle_by_resno(query->targetList, tididx + 1);
            if (tle && tle->expr && IsA(tle->expr, Var))
            {
                Var        *var = (Var *) tle->expr;
                RangeTblEntry *rte;

                if (!IS_SPECIAL_VARNO(var->varno) &&
                    var->varattno == SelfItemPointerAttributeNumber)
                {
                    rte = rt_fetch(var->varno, query->rtable);
                    if (rte)
                    {
                        ItemPointer result;
                        Relation    rel;

                        rel = table_open(rte->relid, AccessShareLock);
                        result = currtid_internal(rel, tid);
                        table_close(rel, AccessShareLock);
                        return result;
                    }
                }
            }
            break;
        }
    }
    elog(ERROR, "currtid cannot handle this view");
    return NULL;
}

currtid_internal()

static ItemPointer currtid_internal ( Relation  rel, ItemPointer  tid  )

static

Definition at line 286 of file tid.c.

References ACL_SELECT, aclcheck_error(), ACLCHECK_OK, currtid_for_view(), elog, ERROR, get_namespace_name(), get_relkind_objtype(), GetLatestSnapshot(), GetUserId(), ItemPointerCopy, palloc(), pg_class_aclcheck(), RelationData::rd_rel, RegisterSnapshot(), RelationGetNamespace, RelationGetRelationName, RelationGetRelid, table_beginscan_tid(), table_endscan(), table_tuple_get_latest_tid(), and UnregisterSnapshot().

Referenced by currtid_byrelname(), and currtid_for_view().

{
    ItemPointer result;
    AclResult   aclresult;
    Snapshot    snapshot;
    TableScanDesc scan;

    result = (ItemPointer) palloc(sizeof(ItemPointerData));

    aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
                                  ACL_SELECT);
    if (aclresult != ACLCHECK_OK)
        aclcheck_error(aclresult, get_relkind_objtype(rel->rd_rel->relkind),
                       RelationGetRelationName(rel));

    if (rel->rd_rel->relkind == RELKIND_VIEW)
        return currtid_for_view(rel, tid);

    if (!RELKIND_HAS_STORAGE(rel->rd_rel->relkind))
        elog(ERROR, "cannot look at latest visible tid for relation \"%s.%s\"",
             get_namespace_name(RelationGetNamespace(rel)),
             RelationGetRelationName(rel));

    ItemPointerCopy(tid, result);

    snapshot = RegisterSnapshot(GetLatestSnapshot());
    scan = table_beginscan_tid(rel, snapshot);
    table_tuple_get_latest_tid(scan, result);
    table_endscan(scan);
    UnregisterSnapshot(snapshot);

    return result;
}

hashtid()

Datum hashtid

(

PG_FUNCTION_ARGS

)

Definition at line 247 of file tid.c.

References hash_any(), sort-test::key, and PG_GETARG_ITEMPOINTER.

{
    ItemPointer key = PG_GETARG_ITEMPOINTER(0);

    /*
     * While you'll probably have a lot of trouble with a compiler that
     * insists on appending pad space to struct ItemPointerData, we can at
     * least make this code work, by not using sizeof(ItemPointerData).
     * Instead rely on knowing the sizes of the component fields.
     */
    return hash_any((unsigned char *) key,
                    sizeof(BlockIdData) + sizeof(OffsetNumber));
}

hashtidextended()

Datum hashtidextended

(

PG_FUNCTION_ARGS

)

Definition at line 262 of file tid.c.

References hash_any_extended(), sort-test::key, PG_GETARG_INT64, and PG_GETARG_ITEMPOINTER.

{
    ItemPointer key = PG_GETARG_ITEMPOINTER(0);
    uint64      seed = PG_GETARG_INT64(1);

    /* As above */
    return hash_any_extended((unsigned char *) key,
                             sizeof(BlockIdData) + sizeof(OffsetNumber),
                             seed);
}

tideq()

Datum tideq

(

PG_FUNCTION_ARGS

)

Definition at line 166 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_BOOL.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_BOOL(ItemPointerCompare(arg1, arg2) == 0);
}

tidge()

Datum tidge

(

PG_FUNCTION_ARGS

)

Definition at line 211 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_BOOL.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_BOOL(ItemPointerCompare(arg1, arg2) >= 0);
}

tidgt()

Datum tidgt

(

PG_FUNCTION_ARGS

)

Definition at line 202 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_BOOL.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_BOOL(ItemPointerCompare(arg1, arg2) > 0);
}

tidin()

Datum tidin

(

PG_FUNCTION_ARGS

)

Definition at line 57 of file tid.c.

References DELIM, ereport, errcode(), errmsg(), ERROR, i, ItemPointerSet, LDELIM, NTIDARGS, palloc(), PG_GETARG_CSTRING, PG_RETURN_ITEMPOINTER, RDELIM, and generate_unaccent_rules::str.

Referenced by make_tuple_from_result_row().

{
    char       *str = PG_GETARG_CSTRING(0);
    char       *p,
               *coord[NTIDARGS];
    int         i;
    ItemPointer result;
    BlockNumber blockNumber;
    OffsetNumber offsetNumber;
    char       *badp;
    int         hold_offset;

    for (i = 0, p = str; *p && i < NTIDARGS && *p != RDELIM; p++)
        if (*p == DELIM || (*p == LDELIM && !i))
            coord[i++] = p + 1;

    if (i < NTIDARGS)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                 errmsg("invalid input syntax for type %s: \"%s\"",
                        "tid", str)));

    errno = 0;
    blockNumber = strtoul(coord[0], &badp, 10);
    if (errno || *badp != DELIM)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                 errmsg("invalid input syntax for type %s: \"%s\"",
                        "tid", str)));

    hold_offset = strtol(coord[1], &badp, 10);
    if (errno || *badp != RDELIM ||
        hold_offset > USHRT_MAX || hold_offset < 0)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                 errmsg("invalid input syntax for type %s: \"%s\"",
                        "tid", str)));

    offsetNumber = hold_offset;

    result = (ItemPointer) palloc(sizeof(ItemPointerData));

    ItemPointerSet(result, blockNumber, offsetNumber);

    PG_RETURN_ITEMPOINTER(result);
}

tidlarger()

Datum tidlarger

(

PG_FUNCTION_ARGS

)

Definition at line 229 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_ITEMPOINTER.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_ITEMPOINTER(ItemPointerCompare(arg1, arg2) >= 0 ? arg1 : arg2);
}

tidle()

Datum tidle

(

PG_FUNCTION_ARGS

)

Definition at line 193 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_BOOL.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_BOOL(ItemPointerCompare(arg1, arg2) <= 0);
}

tidlt()

Datum tidlt

(

PG_FUNCTION_ARGS

)

Definition at line 184 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_BOOL.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_BOOL(ItemPointerCompare(arg1, arg2) < 0);
}

tidne()

Datum tidne

(

PG_FUNCTION_ARGS

)

Definition at line 175 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_BOOL.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_BOOL(ItemPointerCompare(arg1, arg2) != 0);
}

tidout()

Datum tidout

(

PG_FUNCTION_ARGS

)

Definition at line 109 of file tid.c.

References buf, ItemPointerGetBlockNumberNoCheck, ItemPointerGetOffsetNumberNoCheck, PG_GETARG_ITEMPOINTER, PG_RETURN_CSTRING, pstrdup(), and snprintf.

Referenced by pgrowlocks().

{
    ItemPointer itemPtr = PG_GETARG_ITEMPOINTER(0);
    BlockNumber blockNumber;
    OffsetNumber offsetNumber;
    char        buf[32];

    blockNumber = ItemPointerGetBlockNumberNoCheck(itemPtr);
    offsetNumber = ItemPointerGetOffsetNumberNoCheck(itemPtr);

    /* Perhaps someday we should output this as a record. */
    snprintf(buf, sizeof(buf), "(%u,%u)", blockNumber, offsetNumber);

    PG_RETURN_CSTRING(pstrdup(buf));
}

tidrecv()

Datum tidrecv

(

PG_FUNCTION_ARGS

)

Definition at line 129 of file tid.c.

References buf, ItemPointerSet, palloc(), PG_GETARG_POINTER, PG_RETURN_ITEMPOINTER, and pq_getmsgint().

{
    StringInfo  buf = (StringInfo) PG_GETARG_POINTER(0);
    ItemPointer result;
    BlockNumber blockNumber;
    OffsetNumber offsetNumber;

    blockNumber = pq_getmsgint(buf, sizeof(blockNumber));
    offsetNumber = pq_getmsgint(buf, sizeof(offsetNumber));

    result = (ItemPointer) palloc(sizeof(ItemPointerData));

    ItemPointerSet(result, blockNumber, offsetNumber);

    PG_RETURN_ITEMPOINTER(result);
}

tidsend()

Datum tidsend

(

PG_FUNCTION_ARGS

)

Definition at line 150 of file tid.c.

References buf, ItemPointerGetBlockNumberNoCheck, ItemPointerGetOffsetNumberNoCheck, PG_GETARG_ITEMPOINTER, PG_RETURN_BYTEA_P, pq_begintypsend(), pq_endtypsend(), pq_sendint16(), and pq_sendint32().

{
    ItemPointer itemPtr = PG_GETARG_ITEMPOINTER(0);
    StringInfoData buf;

    pq_begintypsend(&buf);
    pq_sendint32(&buf, ItemPointerGetBlockNumberNoCheck(itemPtr));
    pq_sendint16(&buf, ItemPointerGetOffsetNumberNoCheck(itemPtr));
    PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}

tidsmaller()

Datum tidsmaller

(

PG_FUNCTION_ARGS

)

Definition at line 238 of file tid.c.

References ItemPointerCompare(), PG_GETARG_ITEMPOINTER, and PG_RETURN_ITEMPOINTER.

{
    ItemPointer arg1 = PG_GETARG_ITEMPOINTER(0);
    ItemPointer arg2 = PG_GETARG_ITEMPOINTER(1);

    PG_RETURN_ITEMPOINTER(ItemPointerCompare(arg1, arg2) <= 0 ? arg1 : arg2);
}