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Diffstat (limited to 'contrib/btree_gin/btree_gin.c')
| -rw-r--r-- | contrib/btree_gin/btree_gin.c | 513 |
1 files changed, 513 insertions, 0 deletions
diff --git a/contrib/btree_gin/btree_gin.c b/contrib/btree_gin/btree_gin.c new file mode 100644 index 0000000..b09bb8d --- /dev/null +++ b/contrib/btree_gin/btree_gin.c @@ -0,0 +1,513 @@ +/* + * contrib/btree_gin/btree_gin.c + */ +#include "postgres.h" + +#include <limits.h> + +#include "access/stratnum.h" +#include "utils/builtins.h" +#include "utils/bytea.h" +#include "utils/cash.h" +#include "utils/date.h" +#include "utils/float.h" +#include "utils/inet.h" +#include "utils/numeric.h" +#include "utils/timestamp.h" +#include "utils/uuid.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; + /* FALLTHROUGH */ + 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(CallerFInfoFunctionCall2(data->typecmp, + fcinfo->flinfo, + 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 = PG_INT64_MIN; + v->day = PG_INT32_MIN; + v->month = PG_INT32_MIN; + 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_macaddr8(void) +{ + macaddr8 *v = palloc0(sizeof(macaddr8)); + + return Macaddr8PGetDatum(v); +} + +GIN_SUPPORT(macaddr8, false, leftmostvalue_macaddr8, macaddr8_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) + +GIN_SUPPORT(bpchar, true, leftmostvalue_text, bpcharcmp) + +static Datum +leftmostvalue_char(void) +{ + return CharGetDatum(0); +} + +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) + +/* + * Use a similar trick to that used for numeric for enums, since we don't + * actually know the leftmost value of any enum without knowing the concrete + * type, so we use a dummy leftmost value of InvalidOid. + * + * Note that we use CallerFInfoFunctionCall2 here so that enum_cmp + * gets a valid fn_extra to work with. Unlike most other type comparison + * routines it needs it, so we can't use DirectFunctionCall2. + */ + +#define ENUM_IS_LEFTMOST(x) ((x) == InvalidOid) + +PG_FUNCTION_INFO_V1(gin_enum_cmp); + +Datum +gin_enum_cmp(PG_FUNCTION_ARGS) +{ + Oid a = PG_GETARG_OID(0); + Oid b = PG_GETARG_OID(1); + int res = 0; + + if (ENUM_IS_LEFTMOST(a)) + { + res = (ENUM_IS_LEFTMOST(b)) ? 0 : -1; + } + else if (ENUM_IS_LEFTMOST(b)) + { + res = 1; + } + else + { + res = DatumGetInt32(CallerFInfoFunctionCall2(enum_cmp, + fcinfo->flinfo, + PG_GET_COLLATION(), + ObjectIdGetDatum(a), + ObjectIdGetDatum(b))); + } + + PG_RETURN_INT32(res); +} + +static Datum +leftmostvalue_enum(void) +{ + return ObjectIdGetDatum(InvalidOid); +} + +GIN_SUPPORT(anyenum, false, leftmostvalue_enum, gin_enum_cmp) + +static Datum +leftmostvalue_uuid(void) +{ + /* + * palloc0 will create the UUID with all zeroes: + * "00000000-0000-0000-0000-000000000000" + */ + pg_uuid_t *retval = (pg_uuid_t *) palloc0(sizeof(pg_uuid_t)); + + return UUIDPGetDatum(retval); +} + +GIN_SUPPORT(uuid, false, leftmostvalue_uuid, uuid_cmp) + +static Datum +leftmostvalue_name(void) +{ + NameData *result = (NameData *) palloc0(NAMEDATALEN); + + return NameGetDatum(result); +} + +GIN_SUPPORT(name, false, leftmostvalue_name, btnamecmp) + +static Datum +leftmostvalue_bool(void) +{ + return BoolGetDatum(false); +} + +GIN_SUPPORT(bool, false, leftmostvalue_bool, btboolcmp) |