mirror of
https://github.com/postgres/postgres.git
synced 2025-10-29 22:49:41 +03:00
3a0d473192
This makes almost all core code follow the policy introduced in the previous commit. Specific decisions: - Text search support functions with char* and length arguments, such as prsstart and lexize, may receive unaligned strings. I doubt maintainers of non-core text search code will notice. - Use plain VARDATA() on values detoasted or synthesized earlier in the same function. Use VARDATA_ANY() on varlenas sourced outside the function, even if they happen to always have four-byte headers. As an exception, retain the universal practice of using VARDATA() on return values of SendFunctionCall(). - Retain PG_GETARG_BYTEA_P() in pageinspect. (Page images are too large for a one-byte header, so this misses no optimization.) Sites that do not call get_page_from_raw() typically need the four-byte alignment. - For now, do not change btree_gist. Its use of four-byte headers in memory is partly entangled with storage of 4-byte headers inside GBT_VARKEY, on disk. - For now, do not change gtrgm_consistent() or gtrgm_distance(). They incorporate the varlena header into a cache, and there are multiple credible implementation strategies to consider.
128 lines
3.3 KiB
C
128 lines
3.3 KiB
C
/*
|
|
* contrib/spi/autoinc.c
|
|
*/
|
|
#include "postgres.h"
|
|
|
|
#include "access/htup_details.h"
|
|
#include "catalog/pg_type.h"
|
|
#include "commands/sequence.h"
|
|
#include "commands/trigger.h"
|
|
#include "executor/spi.h"
|
|
#include "utils/builtins.h"
|
|
#include "utils/rel.h"
|
|
|
|
PG_MODULE_MAGIC;
|
|
|
|
PG_FUNCTION_INFO_V1(autoinc);
|
|
|
|
Datum
|
|
autoinc(PG_FUNCTION_ARGS)
|
|
{
|
|
TriggerData *trigdata = (TriggerData *) fcinfo->context;
|
|
Trigger *trigger; /* to get trigger name */
|
|
int nargs; /* # of arguments */
|
|
int *chattrs; /* attnums of attributes to change */
|
|
int chnattrs = 0; /* # of above */
|
|
Datum *newvals; /* vals of above */
|
|
bool *newnulls; /* null flags for above */
|
|
char **args; /* arguments */
|
|
char *relname; /* triggered relation name */
|
|
Relation rel; /* triggered relation */
|
|
HeapTuple rettuple = NULL;
|
|
TupleDesc tupdesc; /* tuple description */
|
|
bool isnull;
|
|
int i;
|
|
|
|
if (!CALLED_AS_TRIGGER(fcinfo))
|
|
/* internal error */
|
|
elog(ERROR, "not fired by trigger manager");
|
|
if (!TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
|
|
/* internal error */
|
|
elog(ERROR, "must be fired for row");
|
|
if (!TRIGGER_FIRED_BEFORE(trigdata->tg_event))
|
|
/* internal error */
|
|
elog(ERROR, "must be fired before event");
|
|
|
|
if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
|
|
rettuple = trigdata->tg_trigtuple;
|
|
else if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
|
|
rettuple = trigdata->tg_newtuple;
|
|
else
|
|
/* internal error */
|
|
elog(ERROR, "cannot process DELETE events");
|
|
|
|
rel = trigdata->tg_relation;
|
|
relname = SPI_getrelname(rel);
|
|
|
|
trigger = trigdata->tg_trigger;
|
|
|
|
nargs = trigger->tgnargs;
|
|
if (nargs <= 0 || nargs % 2 != 0)
|
|
/* internal error */
|
|
elog(ERROR, "autoinc (%s): even number gt 0 of arguments was expected", relname);
|
|
|
|
args = trigger->tgargs;
|
|
tupdesc = rel->rd_att;
|
|
|
|
chattrs = (int *) palloc(nargs / 2 * sizeof(int));
|
|
newvals = (Datum *) palloc(nargs / 2 * sizeof(Datum));
|
|
newnulls = (bool *) palloc(nargs / 2 * sizeof(bool));
|
|
|
|
for (i = 0; i < nargs;)
|
|
{
|
|
int attnum = SPI_fnumber(tupdesc, args[i]);
|
|
int32 val;
|
|
Datum seqname;
|
|
|
|
if (attnum <= 0)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
|
|
errmsg("\"%s\" has no attribute \"%s\"",
|
|
relname, args[i])));
|
|
|
|
if (SPI_gettypeid(tupdesc, attnum) != INT4OID)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
|
|
errmsg("attribute \"%s\" of \"%s\" must be type INT4",
|
|
args[i], relname)));
|
|
|
|
val = DatumGetInt32(SPI_getbinval(rettuple, tupdesc, attnum, &isnull));
|
|
|
|
if (!isnull && val != 0)
|
|
{
|
|
i += 2;
|
|
continue;
|
|
}
|
|
|
|
i++;
|
|
chattrs[chnattrs] = attnum;
|
|
seqname = CStringGetTextDatum(args[i]);
|
|
newvals[chnattrs] = DirectFunctionCall1(nextval, seqname);
|
|
/* nextval now returns int64; coerce down to int32 */
|
|
newvals[chnattrs] = Int32GetDatum((int32) DatumGetInt64(newvals[chnattrs]));
|
|
if (DatumGetInt32(newvals[chnattrs]) == 0)
|
|
{
|
|
newvals[chnattrs] = DirectFunctionCall1(nextval, seqname);
|
|
newvals[chnattrs] = Int32GetDatum((int32) DatumGetInt64(newvals[chnattrs]));
|
|
}
|
|
newnulls[chnattrs] = false;
|
|
pfree(DatumGetTextPP(seqname));
|
|
chnattrs++;
|
|
i++;
|
|
}
|
|
|
|
if (chnattrs > 0)
|
|
{
|
|
rettuple = heap_modify_tuple_by_cols(rettuple, tupdesc,
|
|
chnattrs, chattrs,
|
|
newvals, newnulls);
|
|
}
|
|
|
|
pfree(relname);
|
|
pfree(chattrs);
|
|
pfree(newvals);
|
|
pfree(newnulls);
|
|
|
|
return PointerGetDatum(rettuple);
|
|
}
|