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Postgres FD Implementation
Commit 84b6d5f3 authored by Robert Haas's avatar Robert Haas
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Remove partial, broken support for NULL pointers when fetching attributes. 

Previously, fastgetattr() and heap_getattr() tested their fourth argument
against a null pointer, but any attempt to use them with a literal-NULL
fourth argument evaluated to *(void *)0, resulting in a compiler error.
Remove these NULL tests to avoid leading future readers of this code to
believe that this has a chance of working.  Also clean up related legacy
code in nocachegetattr(), heap_getsysattr(), and nocache_index_getattr().

The new coding standard is that any code which calls a getattr-type
function or macro which takes an isnull argument MUST pass a valid
boolean pointer.  Per discussion with Bruce Momjian, Tom Lane, Alvaro
Herrera.
parent 8b9fa7a9
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Showing with 36 additions and 109 deletions
src/backend/access/common/heaptuple.c
View file @ 84b6d5f3
......@@ -50,7 +50,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/common/heaptuple.c,v 1.129 2010/01/02 16:57:33 momjian Exp $
* $PostgreSQL: pgsql/src/backend/access/common/heaptuple.c,v 1.130 2010/01/10 04:26:36 rhaas Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -323,8 +323,7 @@ heap_attisnull(HeapTuple tup, int attnum)
Datum
nocachegetattr(HeapTuple tuple,
int attnum,
TupleDesc tupleDesc,
bool *isnull)
TupleDesc tupleDesc)
{
HeapTupleHeader tup = tuple->t_data;
Form_pg_attribute *att = tupleDesc->attrs;
......@@ -333,8 +332,6 @@ nocachegetattr(HeapTuple tuple,
bool slow = false; /* do we have to walk attrs? */
int off; /* current offset within data */
(void) isnull; /* not used */
/* ----------------
* Three cases:
*
......@@ -344,68 +341,32 @@ nocachegetattr(HeapTuple tuple,
* ----------------
*/
#ifdef IN_MACRO
/* This is handled in the macro */
Assert(attnum > 0);
if (isnull)
*isnull = false;
#endif
attnum--;
if (HeapTupleNoNulls(tuple))
{
#ifdef IN_MACRO
/* This is handled in the macro */
if (att[attnum]->attcacheoff >= 0)
{
return fetchatt(att[attnum],
(char *) tup + tup->t_hoff +
att[attnum]->attcacheoff);
}
#endif
}
else
if (!HeapTupleNoNulls(tuple))
{
/*
* there's a null somewhere in the tuple
*
* check to see if desired att is null
* check to see if any preceding bits are null...
*/
int byte = attnum >> 3;
int finalbit = attnum & 0x07;
#ifdef IN_MACRO
/* This is handled in the macro */
if (att_isnull(attnum, bp))
{
if (isnull)
*isnull = true;
return (Datum) NULL;
}
#endif
/*
* Now check to see if any preceding bits are null...
*/
/* check for nulls "before" final bit of last byte */
if ((~bp[byte]) & ((1 << finalbit) - 1))
slow = true;
else
{
int byte = attnum >> 3;
int finalbit = attnum & 0x07;
/* check for nulls in any "earlier" bytes */
int i;
/* check for nulls "before" final bit of last byte */
if ((~bp[byte]) & ((1 << finalbit) - 1))
slow = true;
else
for (i = 0; i < byte; i++)
{
/* check for nulls in any "earlier" bytes */
int i;
for (i = 0; i < byte; i++)
if (bp[i] != 0xFF)
{
if (bp[i] != 0xFF)
{
slow = true;
break;
}
slow = true;
break;
}
}
}
......@@ -567,8 +528,7 @@ heap_getsysattr(HeapTuple tup, int attnum, TupleDesc tupleDesc, bool *isnull)
Assert(tup);
/* Currently, no sys attribute ever reads as NULL. */
if (isnull)
*isnull = false;
*isnull = false;
switch (attnum)
{
......
src/backend/access/common/indextuple.c
View file @ 84b6d5f3
......@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/common/indextuple.c,v 1.90 2010/01/02 16:57:33 momjian Exp $
* $PostgreSQL: pgsql/src/backend/access/common/indextuple.c,v 1.91 2010/01/10 04:26:36 rhaas Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -200,8 +200,7 @@ index_form_tuple(TupleDesc tupleDescriptor,
Datum
nocache_index_getattr(IndexTuple tup,
int attnum,
TupleDesc tupleDesc,
bool *isnull)
TupleDesc tupleDesc)
{
Form_pg_attribute *att = tupleDesc->attrs;
char *tp; /* ptr to data part of tuple */
......@@ -210,8 +209,6 @@ nocache_index_getattr(IndexTuple tup,
int data_off; /* tuple data offset */
int off; /* current offset within data */
(void) isnull; /* not used */
/* ----------------
* Three cases:
*
......@@ -221,31 +218,11 @@ nocache_index_getattr(IndexTuple tup,
* ----------------
*/
#ifdef IN_MACRO
/* This is handled in the macro */
Assert(PointerIsValid(isnull));
Assert(attnum > 0);
*isnull = false;
#endif
data_off = IndexInfoFindDataOffset(tup->t_info);
attnum--;
if (!IndexTupleHasNulls(tup))
{
#ifdef IN_MACRO
/* This is handled in the macro */
if (att[attnum]->attcacheoff >= 0)
{
return fetchatt(att[attnum],
(char *) tup + data_off +
att[attnum]->attcacheoff);
}
#endif
}
else
if (IndexTupleHasNulls(tup))
{
/*
* there's a null somewhere in the tuple
......@@ -256,16 +233,6 @@ nocache_index_getattr(IndexTuple tup,
/* XXX "knows" t_bits are just after fixed tuple header! */
bp = (bits8 *) ((char *) tup + sizeof(IndexTupleData));
#ifdef IN_MACRO
/* This is handled in the macro */
if (att_isnull(attnum, bp))
{
*isnull = true;
return (Datum) NULL;
}
#endif
/*
* Now check to see if any preceding bits are null...
*/
......
src/backend/access/heap/heapam.c
View file @ 84b6d5f3
......@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.280 2010/01/02 16:57:34 momjian Exp $
* $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.281 2010/01/10 04:26:36 rhaas Exp $
*
*
* INTERFACE ROUTINES
......@@ -834,7 +834,7 @@ fastgetattr(HeapTuple tup, int attnum, TupleDesc tupleDesc,
return (
(attnum) > 0 ?
(
((isnull) ? (*(isnull) = false) : (dummyret) NULL),
(*(isnull) = false),
HeapTupleNoNulls(tup) ?
(
(tupleDesc)->attrs[(attnum) - 1]->attcacheoff >= 0 ?
......@@ -844,18 +844,18 @@ fastgetattr(HeapTuple tup, int attnum, TupleDesc tupleDesc,
(tupleDesc)->attrs[(attnum) - 1]->attcacheoff)
)
:
nocachegetattr((tup), (attnum), (tupleDesc), (isnull))
nocachegetattr((tup), (attnum), (tupleDesc))
)
:
(
att_isnull((attnum) - 1, (tup)->t_data->t_bits) ?
(
((isnull) ? (*(isnull) = true) : (dummyret) NULL),
(*(isnull) = true),
(Datum) NULL
)
:
(
nocachegetattr((tup), (attnum), (tupleDesc), (isnull))
nocachegetattr((tup), (attnum), (tupleDesc))
)
)
)
......
src/include/access/htup.h
View file @ 84b6d5f3
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/htup.h,v 1.109 2010/01/02 16:58:00 momjian Exp $
* $PostgreSQL: pgsql/src/include/access/htup.h,v 1.110 2010/01/10 04:26:36 rhaas Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -763,7 +763,7 @@ extern void HeapTupleHeaderAdjustCmax(HeapTupleHeader tup,
#define fastgetattr(tup, attnum, tupleDesc, isnull) \
( \
AssertMacro((attnum) > 0), \
(((isnull) != NULL) ? (*(isnull) = false) : (dummyret)NULL), \
(*(isnull) = false), \
HeapTupleNoNulls(tup) ? \
( \
(tupleDesc)->attrs[(attnum)-1]->attcacheoff >= 0 ? \
......@@ -773,18 +773,18 @@ extern void HeapTupleHeaderAdjustCmax(HeapTupleHeader tup,
(tupleDesc)->attrs[(attnum)-1]->attcacheoff) \
) \
: \
nocachegetattr((tup), (attnum), (tupleDesc), (isnull)) \
nocachegetattr((tup), (attnum), (tupleDesc)) \
) \
: \
( \
att_isnull((attnum)-1, (tup)->t_data->t_bits) ? \
( \
(((isnull) != NULL) ? (*(isnull) = true) : (dummyret)NULL), \
(*(isnull) = true), \
(Datum)NULL \
) \
: \
( \
nocachegetattr((tup), (attnum), (tupleDesc), (isnull)) \
nocachegetattr((tup), (attnum), (tupleDesc)) \
) \
) \
)
......@@ -818,7 +818,7 @@ extern Datum fastgetattr(HeapTuple tup, int attnum, TupleDesc tupleDesc,
( \
((attnum) > (int) HeapTupleHeaderGetNatts((tup)->t_data)) ? \
( \
(((isnull) != NULL) ? (*(isnull) = true) : (dummyret)NULL), \
(*(isnull) = true), \
(Datum)NULL \
) \
: \
......@@ -838,7 +838,7 @@ extern void heap_fill_tuple(TupleDesc tupleDesc,
uint16 *infomask, bits8 *bit);
extern bool heap_attisnull(HeapTuple tup, int attnum);
extern Datum nocachegetattr(HeapTuple tup, int attnum,
TupleDesc att, bool *isnull);
TupleDesc att);
extern Datum heap_getsysattr(HeapTuple tup, int attnum, TupleDesc tupleDesc,
bool *isnull);
extern HeapTuple heap_copytuple(HeapTuple tuple);
......
src/include/access/itup.h
View file @ 84b6d5f3
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/itup.h,v 1.53 2010/01/02 16:58:00 momjian Exp $
* $PostgreSQL: pgsql/src/include/access/itup.h,v 1.54 2010/01/10 04:26:36 rhaas Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -110,7 +110,7 @@ typedef IndexAttributeBitMapData *IndexAttributeBitMap;
+ (tupleDesc)->attrs[(attnum)-1]->attcacheoff) \
) \
: \
nocache_index_getattr((tup), (attnum), (tupleDesc), (isnull)) \
nocache_index_getattr((tup), (attnum), (tupleDesc)) \
) \
: \
( \
......@@ -121,7 +121,7 @@ typedef IndexAttributeBitMapData *IndexAttributeBitMap;
) \
: \
( \
nocache_index_getattr((tup), (attnum), (tupleDesc), (isnull)) \
nocache_index_getattr((tup), (attnum), (tupleDesc)) \
) \
) \
)
......@@ -142,7 +142,7 @@ typedef IndexAttributeBitMapData *IndexAttributeBitMap;
extern IndexTuple index_form_tuple(TupleDesc tupleDescriptor,
Datum *values, bool *isnull);
extern Datum nocache_index_getattr(IndexTuple tup, int attnum,
TupleDesc tupleDesc, bool *isnull);
TupleDesc tupleDesc);
extern void index_deform_tuple(IndexTuple tup, TupleDesc tupleDescriptor,
Datum *values, bool *isnull);
extern IndexTuple CopyIndexTuple(IndexTuple source);
......
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