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Have crosstab variants treat NULL rowid as a category in its own right,

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per suggestion from Tom Lane. This fixes crash-bug reported by Stefan
Schwarzer.
This commit is contained in:
Joe Conway
2007-11-10 05:02:22 +00:00
parent fcc3ac19fd
commit 8145f00f27
4 changed files with 139 additions and 96 deletions
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138
contrib/tablefunc/tablefunc.c
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@ -106,6 +106,18 @@ typedef struct
} \
} while (0)
#define xpstrdup(tgtvar_, srcvar_) \
do { \
if (srcvar_) \
tgtvar_ = pstrdup(srcvar_); \
else \
tgtvar_ = NULL; \
} while (0)
#define xstreq(tgtvar_, srcvar_) \
(((tgtvar_ == NULL) && (srcvar_ == NULL)) || \
((tgtvar_ != NULL) && (srcvar_ != NULL) && (strcmp(tgtvar_, srcvar_) == 0)))
/* sign, 10 digits, '\0' */
#define INT32_STRLEN 12
@ -359,6 +371,7 @@ crosstab(PG_FUNCTION_ARGS)
crosstab_fctx *fctx;
int i;
int num_categories;
bool firstpass = false;
MemoryContext oldcontext;
/* stuff done only on the first call of the function */
@ -488,6 +501,7 @@ crosstab(PG_FUNCTION_ARGS)
funcctx->max_calls = proc;
MemoryContextSwitchTo(oldcontext);
firstpass = true;
}
/* stuff done on every call of the function */
@ -522,7 +536,7 @@ crosstab(PG_FUNCTION_ARGS)
HeapTuple tuple;
Datum result;
char **values;
bool allnulls = true;
bool skip_tuple = false;
while (true)
{
@ -553,35 +567,42 @@ crosstab(PG_FUNCTION_ARGS)
/*
* If this is the first pass through the values for this
* rowid set it, otherwise make sure it hasn't changed on
* us. Also check to see if the rowid is the same as that
* of the last tuple sent -- if so, skip this tuple
* entirely
* rowid, set the first column to rowid
*/
if (i == 0)
values[0] = pstrdup(rowid);
if ((rowid != NULL) && (strcmp(rowid, values[0]) == 0))
{
if ((lastrowid != NULL) && (strcmp(rowid, lastrowid) == 0))
break;
else if (allnulls == true)
allnulls = false;
xpstrdup(values[0], rowid);
/*
* Get the next category item value, which is alway
* Check to see if the rowid is the same as that of the last
* tuple sent -- if so, skip this tuple entirely
*/
if (!firstpass && xstreq(lastrowid, rowid))
{
skip_tuple = true;
break;
}
}
/*
* If rowid hasn't changed on us, continue building the
* ouput tuple.
*/
if (xstreq(rowid, values[0]))
{
/*
* Get the next category item value, which is always
* attribute number three.
*
* Be careful to sssign the value to the array index
* based on which category we are presently
* processing.
* Be careful to assign the value to the array index based
* on which category we are presently processing.
*/
values[1 + i] = SPI_getvalue(spi_tuple, spi_tupdesc, 3);
/*
* increment the counter since we consume a row for
* each category, but not for last pass because the
* API will do that for us
* increment the counter since we consume a row for each
* category, but not for last pass because the API will do
* that for us
*/
if (i < (num_categories - 1))
call_cntr = ++funcctx->call_cntr;
@ -589,33 +610,29 @@ crosstab(PG_FUNCTION_ARGS)
else
{
/*
* We'll fill in NULLs for the missing values, but we
* need to decrement the counter since this sql result
* row doesn't belong to the current output tuple.
* We'll fill in NULLs for the missing values, but we need
* to decrement the counter since this sql result row
* doesn't belong to the current output tuple.
*/
call_cntr = --funcctx->call_cntr;
break;
}
if (rowid != NULL)
xpfree(rowid);
xpfree(rowid);
}
/*
* switch to memory context appropriate for multiple function
* calls
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
xpfree(fctx->lastrowid);
xpstrdup(fctx->lastrowid, values[0]);
lastrowid = fctx->lastrowid;
if (values[0] != NULL)
{
/*
* switch to memory context appropriate for multiple
* function calls
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
MemoryContextSwitchTo(oldcontext);
lastrowid = fctx->lastrowid = pstrdup(values[0]);
MemoryContextSwitchTo(oldcontext);
}
if (!allnulls)
if (!skip_tuple)
{
/* build the tuple */
tuple = BuildTupleFromCStrings(attinmeta, values);
@ -634,8 +651,8 @@ crosstab(PG_FUNCTION_ARGS)
else
{
/*
* Skipping this tuple entirely, but we need to advance
* the counter like the API would if we had returned one.
* Skipping this tuple entirely, but we need to advance the
* counter like the API would if we had returned one.
*/
call_cntr = ++funcctx->call_cntr;
@ -649,11 +666,14 @@ crosstab(PG_FUNCTION_ARGS)
SPI_finish();
SRF_RETURN_DONE(funcctx);
}
/* need to reset this before the next tuple is started */
skip_tuple = false;
}
}
}
else
/* do when there is no more left */
/* do when there is no more left */
{
/* release SPI related resources */
SPI_finish();
@ -876,6 +896,7 @@ get_crosstab_tuplestore(char *sql,
int ncols = spi_tupdesc->natts;
char *rowid;
char *lastrowid = NULL;
bool firstpass = true;
int i,
j;
int result_ncols;
@ -940,41 +961,36 @@ get_crosstab_tuplestore(char *sql,
/* get the rowid from the current sql result tuple */
rowid = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
/* if rowid is null, skip this tuple entirely */
if (rowid == NULL)
continue;
/*
* if we're on a new output row, grab the column values up to
* column N-2 now
*/
if ((lastrowid == NULL) || (strcmp(rowid, lastrowid) != 0))
if (firstpass || !xstreq(lastrowid, rowid))
{
/*
* a new row means we need to flush the old one first,
* unless we're on the very first row
* a new row means we need to flush the old one first, unless
* we're on the very first row
*/
if (lastrowid != NULL)
if (!firstpass)
{
/*
* switch to appropriate context while storing the
* tuple
*/
SPIcontext = MemoryContextSwitchTo(per_query_ctx);
/* rowid changed, flush the previous output row */
tuple = BuildTupleFromCStrings(attinmeta, values);
/* switch to appropriate context while storing the tuple */
SPIcontext = MemoryContextSwitchTo(per_query_ctx);
tuplestore_puttuple(tupstore, tuple);
MemoryContextSwitchTo(SPIcontext);
for (j = 0; j < result_ncols; j++)
xpfree(values[j]);
/* now reset the context */
MemoryContextSwitchTo(SPIcontext);
}
values[0] = rowid;
for (j = 1; j < ncols - 2; j++)
values[j] = SPI_getvalue(spi_tuple, spi_tupdesc, j + 1);
/* we're no longer on the first pass */
firstpass = false;
}
/* look up the category and fill in the appropriate column */
@ -990,7 +1006,7 @@ get_crosstab_tuplestore(char *sql,
}
xpfree(lastrowid);
lastrowid = pstrdup(rowid);
xpstrdup(lastrowid, rowid);
}
/* switch to appropriate context while storing the tuple */
@ -998,11 +1014,11 @@ get_crosstab_tuplestore(char *sql,
/* flush the last output row */
tuple = BuildTupleFromCStrings(attinmeta, values);
/* switch to appropriate context while storing the tuple */
SPIcontext = MemoryContextSwitchTo(per_query_ctx);
tuplestore_puttuple(tupstore, tuple);
/* now reset the context */
MemoryContextSwitchTo(SPIcontext);
}
if (SPI_finish() != SPI_OK_FINISH)