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postgres/src/backend/utils/adt/mac.c
Tom Lane 31edbadf4a Downgrade implicit casts to text to be assignment-only, except for the ones
from the other string-category types; this eliminates a lot of surprising
interpretations that the parser could formerly make when there was no directly
applicable operator.

Create a general mechanism that supports casts to and from the standard string
types (text,varchar,bpchar) for *every* datatype, by invoking the datatype's
I/O functions.  These new casts are assignment-only in the to-string direction,
explicit-only in the other, and therefore should create no surprising behavior.
Remove a bunch of thereby-obsoleted datatype-specific casting functions.

The "general mechanism" is a new expression node type CoerceViaIO that can
actually convert between *any* two datatypes if their external text
representations are compatible.  This is more general than needed for the
immediate feature, but might be useful in plpgsql or other places in future.

This commit does nothing about the issue that applying the concatenation
operator || to non-text types will now fail, often with strange error messages
due to misinterpreting the operator as array concatenation.  Since it often
(not always) worked before, we should either make it succeed or at least give
a more user-friendly error; but details are still under debate.

Peter Eisentraut and Tom Lane
2007-06-05 21:31:09 +00:00

265 lines
5.4 KiB
C

/*
* PostgreSQL type definitions for MAC addresses.
*
* $PostgreSQL: pgsql/src/backend/utils/adt/mac.c,v 1.38 2007/06/05 21:31:06 tgl Exp $
*/
#include "postgres.h"
#include "access/hash.h"
#include "libpq/pqformat.h"
#include "utils/builtins.h"
#include "utils/inet.h"
/*
* Utility macros used for sorting and comparing:
*/
#define hibits(addr) \
((unsigned long)(((addr)->a<<16)|((addr)->b<<8)|((addr)->c)))
#define lobits(addr) \
((unsigned long)(((addr)->d<<16)|((addr)->e<<8)|((addr)->f)))
/*
* MAC address reader. Accepts several common notations.
*/
Datum
macaddr_in(PG_FUNCTION_ARGS)
{
char *str = PG_GETARG_CSTRING(0);
macaddr *result;
int a,
b,
c,
d,
e,
f;
char junk[2];
int count;
/* %1s matches iff there is trailing non-whitespace garbage */
count = sscanf(str, "%x:%x:%x:%x:%x:%x%1s",
&a, &b, &c, &d, &e, &f, junk);
if (count != 6)
count = sscanf(str, "%x-%x-%x-%x-%x-%x%1s",
&a, &b, &c, &d, &e, &f, junk);
if (count != 6)
count = sscanf(str, "%2x%2x%2x:%2x%2x%2x%1s",
&a, &b, &c, &d, &e, &f, junk);
if (count != 6)
count = sscanf(str, "%2x%2x%2x-%2x%2x%2x%1s",
&a, &b, &c, &d, &e, &f, junk);
if (count != 6)
count = sscanf(str, "%2x%2x.%2x%2x.%2x%2x%1s",
&a, &b, &c, &d, &e, &f, junk);
if (count != 6)
count = sscanf(str, "%2x%2x%2x%2x%2x%2x%1s",
&a, &b, &c, &d, &e, &f, junk);
if (count != 6)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type macaddr: \"%s\"", str)));
if ((a < 0) || (a > 255) || (b < 0) || (b > 255) ||
(c < 0) || (c > 255) || (d < 0) || (d > 255) ||
(e < 0) || (e > 255) || (f < 0) || (f > 255))
ereport(ERROR,
(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
errmsg("invalid octet value in \"macaddr\" value: \"%s\"", str)));
result = (macaddr *) palloc(sizeof(macaddr));
result->a = a;
result->b = b;
result->c = c;
result->d = d;
result->e = e;
result->f = f;
PG_RETURN_MACADDR_P(result);
}
/*
* MAC address output function. Fixed format.
*/
Datum
macaddr_out(PG_FUNCTION_ARGS)
{
macaddr *addr = PG_GETARG_MACADDR_P(0);
char *result;
result = (char *) palloc(32);
snprintf(result, 32, "%02x:%02x:%02x:%02x:%02x:%02x",
addr->a, addr->b, addr->c, addr->d, addr->e, addr->f);
PG_RETURN_CSTRING(result);
}
/*
* macaddr_recv - converts external binary format to macaddr
*
* The external representation is just the six bytes, MSB first.
*/
Datum
macaddr_recv(PG_FUNCTION_ARGS)
{
StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
macaddr *addr;
addr = (macaddr *) palloc(sizeof(macaddr));
addr->a = pq_getmsgbyte(buf);
addr->b = pq_getmsgbyte(buf);
addr->c = pq_getmsgbyte(buf);
addr->d = pq_getmsgbyte(buf);
addr->e = pq_getmsgbyte(buf);
addr->f = pq_getmsgbyte(buf);
PG_RETURN_MACADDR_P(addr);
}
/*
* macaddr_send - converts macaddr to binary format
*/
Datum
macaddr_send(PG_FUNCTION_ARGS)
{
macaddr *addr = PG_GETARG_MACADDR_P(0);
StringInfoData buf;
pq_begintypsend(&buf);
pq_sendbyte(&buf, addr->a);
pq_sendbyte(&buf, addr->b);
pq_sendbyte(&buf, addr->c);
pq_sendbyte(&buf, addr->d);
pq_sendbyte(&buf, addr->e);
pq_sendbyte(&buf, addr->f);
PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}
/*
* Comparison function for sorting:
*/
static int32
macaddr_cmp_internal(macaddr *a1, macaddr *a2)
{
if (hibits(a1) < hibits(a2))
return -1;
else if (hibits(a1) > hibits(a2))
return 1;
else if (lobits(a1) < lobits(a2))
return -1;
else if (lobits(a1) > lobits(a2))
return 1;
else
return 0;
}
Datum
macaddr_cmp(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_INT32(macaddr_cmp_internal(a1, a2));
}
/*
* Boolean comparisons.
*/
Datum
macaddr_lt(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_BOOL(macaddr_cmp_internal(a1, a2) < 0);
}
Datum
macaddr_le(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_BOOL(macaddr_cmp_internal(a1, a2) <= 0);
}
Datum
macaddr_eq(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_BOOL(macaddr_cmp_internal(a1, a2) == 0);
}
Datum
macaddr_ge(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_BOOL(macaddr_cmp_internal(a1, a2) >= 0);
}
Datum
macaddr_gt(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_BOOL(macaddr_cmp_internal(a1, a2) > 0);
}
Datum
macaddr_ne(PG_FUNCTION_ARGS)
{
macaddr *a1 = PG_GETARG_MACADDR_P(0);
macaddr *a2 = PG_GETARG_MACADDR_P(1);
PG_RETURN_BOOL(macaddr_cmp_internal(a1, a2) != 0);
}
/*
* Support function for hash indexes on macaddr.
*/
Datum
hashmacaddr(PG_FUNCTION_ARGS)
{
macaddr *key = PG_GETARG_MACADDR_P(0);
return hash_any((unsigned char *) key, sizeof(macaddr));
}
/*
* Truncation function to allow comparing mac manufacturers.
* From suggestion by Alex Pilosov <alex@pilosoft.com>
*/
Datum
macaddr_trunc(PG_FUNCTION_ARGS)
{
macaddr *addr = PG_GETARG_MACADDR_P(0);
macaddr *result;
result = (macaddr *) palloc(sizeof(macaddr));
result->a = addr->a;
result->b = addr->b;
result->c = addr->c;
result->d = 0;
result->e = 0;
result->f = 0;
PG_RETURN_MACADDR_P(result);
}