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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 05:02:41 +00:00
parent b7f1fe6c46
commit 75ffb44e7f
3 changed files with 92 additions and 59 deletions
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100
contrib/tablefunc/tablefunc.c
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@@ -93,6 +93,18 @@ 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
@@ -299,6 +311,7 @@ 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 */
@@ -420,6 +433,7 @@ crosstab(PG_FUNCTION_ARGS)
funcctx->max_calls = proc;
MemoryContextSwitchTo(oldcontext);
firstpass = true;
}
/* stuff done on every call of the function */
@@ -454,7 +468,7 @@ crosstab(PG_FUNCTION_ARGS)
HeapTuple tuple;
Datum result;
char **values;
bool allnulls = true;
bool skip_tuple = false;
while (true)
{
@@ -485,35 +499,42 @@ 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;
@@ -521,33 +542,29 @@ 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);
@@ -566,8 +583,8 @@ 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;
@@ -581,11 +598,14 @@ 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();