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Allow bit string constants without fully-specified length declaration.
Implement conversion between 8-byte integers and bit strings. Similar to what is done for 4-byte integers.
This commit is contained in:
Thomas G. Lockhart
@ -9,7 +9,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/varbit.c,v 1.22 2002/06/20 20:29:38 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/varbit.c,v 1.23 2002/08/04 06:33:48 thomas Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -98,8 +98,8 @@ bit_in(PG_FUNCTION_ARGS)
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if (atttypmod <= 0)
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atttypmod = bitlen;
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else if (bitlen != atttypmod)
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elog(ERROR, "bit string length does not match type bit(%d)",
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atttypmod);
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elog(ERROR, "Bit string length %d does not match type BIT(%d)",
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bitlen, atttypmod);
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len = VARBITTOTALLEN(atttypmod);
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result = (VarBit *) palloc(len);
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@ -119,7 +119,7 @@ bit_in(PG_FUNCTION_ARGS)
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if (*sp == '1')
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*r |= x;
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else if (*sp != '0')
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elog(ERROR, "cannot parse %c as a binary digit", *sp);
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elog(ERROR, "Cannot parse '%c' as a binary digit", *sp);
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x >>= 1;
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if (x == 0)
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{
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@ -140,7 +140,7 @@ bit_in(PG_FUNCTION_ARGS)
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else if (*sp >= 'a' && *sp <= 'f')
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x = (bits8) (*sp - 'a') + 10;
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else
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elog(ERROR, "cannot parse %c as a hex digit", *sp);
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elog(ERROR, "Cannot parse '%c' as a hex digit", *sp);
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if (bc)
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{
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*r++ |= x;
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@ -214,8 +214,8 @@ bit(PG_FUNCTION_ARGS)
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if (len <= 0 || len == VARBITLEN(arg))
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PG_RETURN_VARBIT_P(arg);
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else
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elog(ERROR, "bit string length does not match type bit(%d)",
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len);
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elog(ERROR, "Bit string length %d does not match type BIT(%d)",
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VARBITLEN(arg), len);
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return 0; /* quiet compiler */
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}
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@ -305,7 +305,7 @@ varbit_in(PG_FUNCTION_ARGS)
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if (atttypmod <= 0)
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atttypmod = bitlen;
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else if (bitlen > atttypmod)
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elog(ERROR, "bit string too long for type bit varying(%d)",
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elog(ERROR, "Bit string too long for type BIT VARYING(%d)",
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atttypmod);
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len = VARBITTOTALLEN(bitlen);
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@ -326,7 +326,7 @@ varbit_in(PG_FUNCTION_ARGS)
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if (*sp == '1')
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*r |= x;
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else if (*sp != '0')
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elog(ERROR, "cannot parse %c as a binary digit", *sp);
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elog(ERROR, "Cannot parse '%c' as a binary digit", *sp);
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x >>= 1;
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if (x == 0)
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{
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@ -347,7 +347,7 @@ varbit_in(PG_FUNCTION_ARGS)
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else if (*sp >= 'a' && *sp <= 'f')
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x = (bits8) (*sp - 'a') + 10;
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else
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elog(ERROR, "cannot parse %c as a hex digit", *sp);
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elog(ERROR, "Cannot parse '%c' as a hex digit", *sp);
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if (bc)
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{
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*r++ |= x;
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@ -420,7 +420,7 @@ varbit(PG_FUNCTION_ARGS)
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PG_RETURN_VARBIT_P(arg);
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if (len < VARBITLEN(arg))
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elog(ERROR, "bit string too long for type bit varying(%d)", len);
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elog(ERROR, "Bit string too long for type BIT VARYING(%d)", len);
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rlen = VARBITTOTALLEN(len);
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result = (VarBit *) palloc(rlen);
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@ -812,7 +812,7 @@ bitand(PG_FUNCTION_ARGS)
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bitlen1 = VARBITLEN(arg1);
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bitlen2 = VARBITLEN(arg2);
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if (bitlen1 != bitlen2)
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elog(ERROR, "cannot AND bit strings of different sizes");
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elog(ERROR, "Cannot AND bit strings of different sizes");
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len = VARSIZE(arg1);
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result = (VarBit *) palloc(len);
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VARATT_SIZEP(result) = len;
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@ -850,7 +850,7 @@ bitor(PG_FUNCTION_ARGS)
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bitlen1 = VARBITLEN(arg1);
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bitlen2 = VARBITLEN(arg2);
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if (bitlen1 != bitlen2)
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elog(ERROR, "cannot OR bit strings of different sizes");
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elog(ERROR, "Cannot OR bit strings of different sizes");
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len = VARSIZE(arg1);
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result = (VarBit *) palloc(len);
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VARATT_SIZEP(result) = len;
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@ -894,7 +894,7 @@ bitxor(PG_FUNCTION_ARGS)
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bitlen1 = VARBITLEN(arg1);
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bitlen2 = VARBITLEN(arg2);
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if (bitlen1 != bitlen2)
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elog(ERROR, "cannot XOR bit strings of different sizes");
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elog(ERROR, "Cannot XOR bit strings of different sizes");
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len = VARSIZE(arg1);
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result = (VarBit *) palloc(len);
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VARATT_SIZEP(result) = len;
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@ -1109,7 +1109,7 @@ bittoint4(PG_FUNCTION_ARGS)
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/* Check that the bit string is not too long */
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if (VARBITLEN(arg) > sizeof(int4) * BITS_PER_BYTE)
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elog(ERROR, "bit string is too large to fit in type integer");
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elog(ERROR, "Bit string is too large to fit in type integer");
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result = 0;
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for (r = VARBITS(arg); r < VARBITEND(arg); r++)
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{
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@ -1122,51 +1122,114 @@ bittoint4(PG_FUNCTION_ARGS)
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PG_RETURN_INT32(result);
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}
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Datum
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bitfromint8(PG_FUNCTION_ARGS)
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{
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#ifndef INT64_IS_BUSTED
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int64 a = PG_GETARG_INT64(0);
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VarBit *result;
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bits8 *r;
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int len;
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/* allocate enough space for the bits in an int64 */
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len = VARBITTOTALLEN(sizeof(a) * BITS_PER_BYTE);
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result = (VarBit *) palloc(len);
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VARATT_SIZEP(result) = len;
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VARBITLEN(result) = sizeof(a) * BITS_PER_BYTE;
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/*
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* masks and shifts here are just too painful and we know that an int64
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* has got 8 bytes
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*/
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r = VARBITS(result);
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r[0] = (bits8) ((a >> (7 * BITS_PER_BYTE)) & BITMASK);
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r[1] = (bits8) ((a >> (6 * BITS_PER_BYTE)) & BITMASK);
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r[2] = (bits8) ((a >> (5 * BITS_PER_BYTE)) & BITMASK);
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r[3] = (bits8) ((a >> (4 * BITS_PER_BYTE)) & BITMASK);
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r[4] = (bits8) ((a >> (3 * BITS_PER_BYTE)) & BITMASK);
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r[5] = (bits8) ((a >> (2 * BITS_PER_BYTE)) & BITMASK);
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r[6] = (bits8) ((a >> (1 * BITS_PER_BYTE)) & BITMASK);
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r[7] = (bits8) (a & BITMASK);
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PG_RETURN_VARBIT_P(result);
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#else
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elog(ERROR, "INT64 is not supported on this platform");
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PG_RETURN_NULL();
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#endif
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}
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Datum
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bittoint8(PG_FUNCTION_ARGS)
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{
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#ifndef INT64_IS_BUSTED
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VarBit *arg = PG_GETARG_VARBIT_P(0);
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uint64 result;
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bits8 *r;
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/* Check that the bit string is not too long */
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if (VARBITLEN(arg) > sizeof(result) * BITS_PER_BYTE)
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elog(ERROR, "Bit string is too large to fit in type int64");
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result = 0;
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for (r = VARBITS(arg); r < VARBITEND(arg); r++)
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{
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result <<= BITS_PER_BYTE;
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result |= *r;
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}
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/* Now shift the result to take account of the padding at the end */
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result >>= VARBITPAD(arg);
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PG_RETURN_INT64(result);
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#else
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elog(ERROR, "INT64 is not supported on this platform");
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PG_RETURN_NULL();
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#endif
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}
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/* Determines the position of S2 in the bitstring S1 (1-based string).
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* If S2 does not appear in S1 this function returns 0.
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* If S2 is of length 0 this function returns 1.
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* Compatible in usage with POSITION() functions for other data types.
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*/
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Datum
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bitposition(PG_FUNCTION_ARGS)
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{
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VarBit *str = PG_GETARG_VARBIT_P(0);
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VarBit *substr = PG_GETARG_VARBIT_P(1);
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VarBit *arg = PG_GETARG_VARBIT_P(0);
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int substr_length,
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arg_length,
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str_length,
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i,
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is;
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bits8 *s, /* pointer into substring */
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*p; /* pointer into arg */
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*p; /* pointer into str */
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bits8 cmp, /* shifted substring byte to compare */
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mask1, /* mask for substring byte shifted right */
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mask2, /* mask for substring byte shifted left */
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end_mask, /* pad mask for last substring byte */
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arg_mask; /* pad mask for last argument byte */
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str_mask; /* pad mask for last string byte */
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bool is_match;
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/* Get the substring length */
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substr_length = VARBITLEN(substr);
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arg_length = VARBITLEN(arg);
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str_length = VARBITLEN(str);
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/* Argument has 0 length or substring longer than argument, return 0 */
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if (arg_length == 0 || substr_length > arg_length)
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/* String has zero length or substring longer than string, return 0 */
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if ((str_length == 0) || (substr_length > str_length))
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PG_RETURN_INT32(0);
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/* 0-length means return 1 */
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/* zero-length substring means return 1 */
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if (substr_length == 0)
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PG_RETURN_INT32(1);
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/* Initialise the padding masks */
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end_mask = BITMASK << VARBITPAD(substr);
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arg_mask = BITMASK << VARBITPAD(arg);
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for (i = 0; i < VARBITBYTES(arg) - VARBITBYTES(substr) + 1; i++)
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str_mask = BITMASK << VARBITPAD(str);
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for (i = 0; i < VARBITBYTES(str) - VARBITBYTES(substr) + 1; i++)
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{
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for (is = 0; is < BITS_PER_BYTE; is++)
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{
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is_match = true;
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p = VARBITS(arg) + i;
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p = VARBITS(str) + i;
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mask1 = BITMASK >> is;
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mask2 = ~mask1;
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for (s = VARBITS(substr);
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@ -1176,15 +1239,15 @@ bitposition(PG_FUNCTION_ARGS)
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if (s == VARBITEND(substr) - 1)
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{
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mask1 &= end_mask >> is;
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if (p == VARBITEND(arg) - 1)
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if (p == VARBITEND(str) - 1)
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{
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/* Check that there is enough of arg left */
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if (mask1 & ~arg_mask)
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/* Check that there is enough of str left */
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if (mask1 & ~str_mask)
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{
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is_match = false;
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break;
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}
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mask1 &= arg_mask;
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mask1 &= str_mask;
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}
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}
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is_match = ((cmp ^ *p) & mask1) == 0;
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@ -1192,7 +1255,7 @@ bitposition(PG_FUNCTION_ARGS)
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break;
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/* Move on to the next byte */
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p++;
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if (p == VARBITEND(arg))
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if (p == VARBITEND(str))
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{
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mask2 = end_mask << (BITS_PER_BYTE - is);
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is_match = mask2 == 0;
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@ -1206,19 +1269,19 @@ bitposition(PG_FUNCTION_ARGS)
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if (s == VARBITEND(substr) - 1)
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{
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mask2 &= end_mask << (BITS_PER_BYTE - is);
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if (p == VARBITEND(arg) - 1)
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if (p == VARBITEND(str) - 1)
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{
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if (mask2 & ~arg_mask)
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if (mask2 & ~str_mask)
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{
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is_match = false;
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break;
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}
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mask2 &= arg_mask;
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mask2 &= str_mask;
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}
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}
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is_match = ((cmp ^ *p) & mask2) == 0;
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}
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/* Have we found a match */
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/* Have we found a match? */
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if (is_match)
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PG_RETURN_INT32(i * BITS_PER_BYTE + is + 1);
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}
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