/* * contrib/btree_gin/btree_gin.c */ #include "postgres.h" #include #include "access/stratnum.h" #include "utils/builtins.h" #include "utils/bytea.h" #include "utils/cash.h" #include "utils/date.h" #include "utils/inet.h" #include "utils/numeric.h" #include "utils/timestamp.h" #include "utils/varbit.h" PG_MODULE_MAGIC; typedef struct QueryInfo { StrategyNumber strategy; Datum datum; bool is_varlena; Datum (*typecmp) (FunctionCallInfo); } QueryInfo; /*** GIN support functions shared by all datatypes ***/ static Datum gin_btree_extract_value(FunctionCallInfo fcinfo, bool is_varlena) { Datum datum = PG_GETARG_DATUM(0); int32 *nentries = (int32 *) PG_GETARG_POINTER(1); Datum *entries = (Datum *) palloc(sizeof(Datum)); if (is_varlena) datum = PointerGetDatum(PG_DETOAST_DATUM(datum)); entries[0] = datum; *nentries = 1; PG_RETURN_POINTER(entries); } /* * For BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, and * BTEqualStrategyNumber we want to start the index scan at the * supplied query datum, and work forward. For BTLessStrategyNumber * and BTLessEqualStrategyNumber, we need to start at the leftmost * key, and work forward until the supplied query datum (which must be * sent along inside the QueryInfo structure). */ static Datum gin_btree_extract_query(FunctionCallInfo fcinfo, bool is_varlena, Datum (*leftmostvalue) (void), Datum (*typecmp) (FunctionCallInfo)) { Datum datum = PG_GETARG_DATUM(0); int32 *nentries = (int32 *) PG_GETARG_POINTER(1); StrategyNumber strategy = PG_GETARG_UINT16(2); bool **partialmatch = (bool **) PG_GETARG_POINTER(3); Pointer **extra_data = (Pointer **) PG_GETARG_POINTER(4); Datum *entries = (Datum *) palloc(sizeof(Datum)); QueryInfo *data = (QueryInfo *) palloc(sizeof(QueryInfo)); bool *ptr_partialmatch; *nentries = 1; ptr_partialmatch = *partialmatch = (bool *) palloc(sizeof(bool)); *ptr_partialmatch = false; if (is_varlena) datum = PointerGetDatum(PG_DETOAST_DATUM(datum)); data->strategy = strategy; data->datum = datum; data->is_varlena = is_varlena; data->typecmp = typecmp; *extra_data = (Pointer *) palloc(sizeof(Pointer)); **extra_data = (Pointer) data; switch (strategy) { case BTLessStrategyNumber: case BTLessEqualStrategyNumber: entries[0] = leftmostvalue(); *ptr_partialmatch = true; break; case BTGreaterEqualStrategyNumber: case BTGreaterStrategyNumber: *ptr_partialmatch = true; case BTEqualStrategyNumber: entries[0] = datum; break; default: elog(ERROR, "unrecognized strategy number: %d", strategy); } PG_RETURN_POINTER(entries); } /* * Datum a is a value from extract_query method and for BTLess* * strategy it is a left-most value. So, use original datum from QueryInfo * to decide to stop scanning or not. Datum b is always from index. */ static Datum gin_btree_compare_prefix(FunctionCallInfo fcinfo) { Datum a = PG_GETARG_DATUM(0); Datum b = PG_GETARG_DATUM(1); QueryInfo *data = (QueryInfo *) PG_GETARG_POINTER(3); int32 res, cmp; cmp = DatumGetInt32(DirectFunctionCall2Coll( data->typecmp, PG_GET_COLLATION(), (data->strategy == BTLessStrategyNumber || data->strategy == BTLessEqualStrategyNumber) ? data->datum : a, b)); switch (data->strategy) { case BTLessStrategyNumber: /* If original datum > indexed one then return match */ if (cmp > 0) res = 0; else res = 1; break; case BTLessEqualStrategyNumber: /* The same except equality */ if (cmp >= 0) res = 0; else res = 1; break; case BTEqualStrategyNumber: if (cmp != 0) res = 1; else res = 0; break; case BTGreaterEqualStrategyNumber: /* If original datum <= indexed one then return match */ if (cmp <= 0) res = 0; else res = 1; break; case BTGreaterStrategyNumber: /* If original datum <= indexed one then return match */ /* If original datum == indexed one then continue scan */ if (cmp < 0) res = 0; else if (cmp == 0) res = -1; else res = 1; break; default: elog(ERROR, "unrecognized strategy number: %d", data->strategy); res = 0; } PG_RETURN_INT32(res); } PG_FUNCTION_INFO_V1(gin_btree_consistent); Datum gin_btree_consistent(PG_FUNCTION_ARGS) { bool *recheck = (bool *) PG_GETARG_POINTER(5); *recheck = false; PG_RETURN_BOOL(true); } /*** GIN_SUPPORT macro defines the datatype specific functions ***/ #define GIN_SUPPORT(type, is_varlena, leftmostvalue, typecmp) \ PG_FUNCTION_INFO_V1(gin_extract_value_##type); \ Datum \ gin_extract_value_##type(PG_FUNCTION_ARGS) \ { \ return gin_btree_extract_value(fcinfo, is_varlena); \ } \ PG_FUNCTION_INFO_V1(gin_extract_query_##type); \ Datum \ gin_extract_query_##type(PG_FUNCTION_ARGS) \ { \ return gin_btree_extract_query(fcinfo, \ is_varlena, leftmostvalue, typecmp); \ } \ PG_FUNCTION_INFO_V1(gin_compare_prefix_##type); \ Datum \ gin_compare_prefix_##type(PG_FUNCTION_ARGS) \ { \ return gin_btree_compare_prefix(fcinfo); \ } /*** Datatype specifications ***/ static Datum leftmostvalue_int2(void) { return Int16GetDatum(SHRT_MIN); } GIN_SUPPORT(int2, false, leftmostvalue_int2, btint2cmp) static Datum leftmostvalue_int4(void) { return Int32GetDatum(INT_MIN); } GIN_SUPPORT(int4, false, leftmostvalue_int4, btint4cmp) static Datum leftmostvalue_int8(void) { return Int64GetDatum(PG_INT64_MIN); } GIN_SUPPORT(int8, false, leftmostvalue_int8, btint8cmp) static Datum leftmostvalue_float4(void) { return Float4GetDatum(-get_float4_infinity()); } GIN_SUPPORT(float4, false, leftmostvalue_float4, btfloat4cmp) static Datum leftmostvalue_float8(void) { return Float8GetDatum(-get_float8_infinity()); } GIN_SUPPORT(float8, false, leftmostvalue_float8, btfloat8cmp) static Datum leftmostvalue_money(void) { return Int64GetDatum(PG_INT64_MIN); } GIN_SUPPORT(money, false, leftmostvalue_money, cash_cmp) static Datum leftmostvalue_oid(void) { return ObjectIdGetDatum(0); } GIN_SUPPORT(oid, false, leftmostvalue_oid, btoidcmp) static Datum leftmostvalue_timestamp(void) { return TimestampGetDatum(DT_NOBEGIN); } GIN_SUPPORT(timestamp, false, leftmostvalue_timestamp, timestamp_cmp) GIN_SUPPORT(timestamptz, false, leftmostvalue_timestamp, timestamp_cmp) static Datum leftmostvalue_time(void) { return TimeADTGetDatum(0); } GIN_SUPPORT(time, false, leftmostvalue_time, time_cmp) static Datum leftmostvalue_timetz(void) { TimeTzADT *v = palloc(sizeof(TimeTzADT)); v->time = 0; v->zone = -24 * 3600; /* XXX is that true? */ return TimeTzADTPGetDatum(v); } GIN_SUPPORT(timetz, false, leftmostvalue_timetz, timetz_cmp) static Datum leftmostvalue_date(void) { return DateADTGetDatum(DATEVAL_NOBEGIN); } GIN_SUPPORT(date, false, leftmostvalue_date, date_cmp) static Datum leftmostvalue_interval(void) { Interval *v = palloc(sizeof(Interval)); v->time = DT_NOBEGIN; v->day = 0; v->month = 0; return IntervalPGetDatum(v); } GIN_SUPPORT(interval, false, leftmostvalue_interval, interval_cmp) static Datum leftmostvalue_macaddr(void) { macaddr *v = palloc0(sizeof(macaddr)); return MacaddrPGetDatum(v); } GIN_SUPPORT(macaddr, false, leftmostvalue_macaddr, macaddr_cmp) static Datum leftmostvalue_inet(void) { return DirectFunctionCall1(inet_in, CStringGetDatum("0.0.0.0/0")); } GIN_SUPPORT(inet, true, leftmostvalue_inet, network_cmp) GIN_SUPPORT(cidr, true, leftmostvalue_inet, network_cmp) static Datum leftmostvalue_text(void) { return PointerGetDatum(cstring_to_text_with_len("", 0)); } GIN_SUPPORT(text, true, leftmostvalue_text, bttextcmp) static Datum leftmostvalue_char(void) { return CharGetDatum(SCHAR_MIN); } GIN_SUPPORT(char, false, leftmostvalue_char, btcharcmp) GIN_SUPPORT(bytea, true, leftmostvalue_text, byteacmp) static Datum leftmostvalue_bit(void) { return DirectFunctionCall3(bit_in, CStringGetDatum(""), ObjectIdGetDatum(0), Int32GetDatum(-1)); } GIN_SUPPORT(bit, true, leftmostvalue_bit, bitcmp) static Datum leftmostvalue_varbit(void) { return DirectFunctionCall3(varbit_in, CStringGetDatum(""), ObjectIdGetDatum(0), Int32GetDatum(-1)); } GIN_SUPPORT(varbit, true, leftmostvalue_varbit, bitcmp) /* * Numeric type hasn't a real left-most value, so we use PointerGetDatum(NULL) * (*not* a SQL NULL) to represent that. We can get away with that because * the value returned by our leftmostvalue function will never be stored in * the index nor passed to anything except our compare and prefix-comparison * functions. The same trick could be used for other pass-by-reference types. */ #define NUMERIC_IS_LEFTMOST(x) ((x) == NULL) PG_FUNCTION_INFO_V1(gin_numeric_cmp); Datum gin_numeric_cmp(PG_FUNCTION_ARGS) { Numeric a = (Numeric) PG_GETARG_POINTER(0); Numeric b = (Numeric) PG_GETARG_POINTER(1); int res = 0; if (NUMERIC_IS_LEFTMOST(a)) { res = (NUMERIC_IS_LEFTMOST(b)) ? 0 : -1; } else if (NUMERIC_IS_LEFTMOST(b)) { res = 1; } else { res = DatumGetInt32(DirectFunctionCall2(numeric_cmp, NumericGetDatum(a), NumericGetDatum(b))); } PG_RETURN_INT32(res); } static Datum leftmostvalue_numeric(void) { return PointerGetDatum(NULL); } GIN_SUPPORT(numeric, true, leftmostvalue_numeric, gin_numeric_cmp)