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949a9f043e
Not much to say here --- does what it says on the tin. The "binary"
representation in each case is really just the same as the text format,
though we prefix a version-number byte in case anyone ever feels
motivated to change that. Thus, there's not any expectation of improved
speed or reduced space; the point here is just to allow clients to use
binary format for all columns of a query result or COPY data.
This makes use of the recently added ALTER TYPE support to add binary
I/O functions to an existing data type. As in commit a80818605,
we can piggy-back on there already being a new-for-v13 version of the
ltree extension, so we don't need a new update script file.
Nino Floris, reviewed by Alexander Korotkov and myself
Discussion: https://postgr.es/m/CANmj9Vxx50jOo1L7iSRxd142NyTz6Bdcgg7u9P3Z8o0=HGkYyQ@mail.gmail.com
40 lines
676 B
C
40 lines
676 B
C
/* contrib/ltree/crc32.c */
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/*
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* Implements CRC-32, as used in ltree.
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*
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* Note that the CRC is used in the on-disk format of GiST indexes, so we
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* must stay backwards-compatible!
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*/
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#include "postgres.h"
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#ifdef LOWER_NODE
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#include <ctype.h>
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#define TOLOWER(x) tolower((unsigned char) (x))
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#else
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#define TOLOWER(x) (x)
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#endif
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#include "crc32.h"
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#include "utils/pg_crc.h"
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unsigned int
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ltree_crc32_sz(const char *buf, int size)
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{
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pg_crc32 crc;
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const char *p = buf;
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INIT_TRADITIONAL_CRC32(crc);
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while (size > 0)
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{
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char c = (char) TOLOWER(*p);
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COMP_TRADITIONAL_CRC32(crc, &c, 1);
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size--;
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p++;
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}
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FIN_TRADITIONAL_CRC32(crc);
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return (unsigned int) crc;
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}
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