Re: Table Function API patch (was Re: another SRF question) - Mailing list pgsql-patches

Your patch has been added to the PostgreSQL unapplied patches list at:

    http://candle.pha.pa.us/cgi-bin/pgpatches

I will try to apply it within the next 48 hours.

---------------------------------------------------------------------------


Joe Conway wrote:
> Neil Conway wrote:
> > On Mon, Jul 08, 2002 at 03:52:24PM -0700, Joe Conway wrote:
> >>Nice catch. Here's (I think) a proper fix. This assumes that if
> >>(values[i] != NULL), the datum is the output of the appropriate "in"
> >>function, otherwise the datum is NULL. It saves the extra pass through
> >>the dvalues array too.
> >>
> >>I thought you might want to try it out now without waiting for the patch
> >>to get into cvs. I tested it with a contrived test function and it
> >>worked as desired.
> >
> >
> > Great, seems to work fine here. Thanks for fixing that for me.
> >
>
> Here is a patch for the Table Function API. It fixes a bug found by Neil
> Conway (BuildTupleFromCStrings sets NULL for pass-by-value types when
> intended value is 0). It also implements some other improvements
> suggested by Neil.
>
> If there are no objections, please apply.
>
> Thanks,
>
> Joe
>
>

> Index: src/backend/executor/execTuples.c
> ===================================================================
> RCS file: /opt/src/cvs/pgsql/src/backend/executor/execTuples.c,v
> retrieving revision 1.53
> diff -c -r1.53 execTuples.c
> *** src/backend/executor/execTuples.c    20 Jun 2002 20:29:27 -0000    1.53
> --- src/backend/executor/execTuples.c    8 Jul 2002 22:25:14 -0000
> ***************
> *** 759,764 ****
> --- 759,765 ----
>       natts = tupdesc->natts;
>
>       dvalues = (Datum *) palloc(natts * sizeof(Datum));
> +     nulls = (char *) palloc(natts * sizeof(char));
>
>       /* Call the "in" function for each attribute */
>       for (i = 0; i < natts; i++)
> ***************
> *** 772,793 ****
>               dvalues[i] = FunctionCall3(&attinfuncinfo, CStringGetDatum(values[i]),
>                                           ObjectIdGetDatum(attelem),
>                                           Int32GetDatum(atttypmod));
>           }
>           else
>               dvalues[i] = PointerGetDatum(NULL);
>       }
>
>       /*
>        * Form a tuple
>        */
> -     nulls = (char *) palloc(natts * sizeof(char));
> -     for (i = 0; i < natts; i++)
> -     {
> -         if (DatumGetPointer(dvalues[i]) != NULL)
> -             nulls[i] = ' ';
> -         else
> -             nulls[i] = 'n';
> -     }
>       tuple = heap_formtuple(tupdesc, dvalues, nulls);
>
>       return tuple;
> --- 773,790 ----
>               dvalues[i] = FunctionCall3(&attinfuncinfo, CStringGetDatum(values[i]),
>                                           ObjectIdGetDatum(attelem),
>                                           Int32GetDatum(atttypmod));
> +             nulls[i] = ' ';
>           }
>           else
> +         {
>               dvalues[i] = PointerGetDatum(NULL);
> +             nulls[i] = 'n';
> +         }
>       }
>
>       /*
>        * Form a tuple
>        */
>       tuple = heap_formtuple(tupdesc, dvalues, nulls);
>
>       return tuple;
> Index: src/backend/utils/fmgr/funcapi.c
> ===================================================================
> RCS file: /opt/src/cvs/pgsql/src/backend/utils/fmgr/funcapi.c,v
> retrieving revision 1.1
> diff -c -r1.1 funcapi.c
> *** src/backend/utils/fmgr/funcapi.c    20 Jun 2002 20:37:00 -0000    1.1
> --- src/backend/utils/fmgr/funcapi.c    9 Jul 2002 18:21:15 -0000
> ***************
> *** 52,58 ****
>           retval->call_cntr = 0;
>           retval->max_calls = 0;
>           retval->slot = NULL;
> !         retval->fctx = NULL;
>           retval->attinmeta = NULL;
>           retval->fmctx = fcinfo->flinfo->fn_mcxt;
>
> --- 52,58 ----
>           retval->call_cntr = 0;
>           retval->max_calls = 0;
>           retval->slot = NULL;
> !         retval->user_fctx = NULL;
>           retval->attinmeta = NULL;
>           retval->fmctx = fcinfo->flinfo->fn_mcxt;
>
> ***************
> *** 71,76 ****
> --- 71,93 ----
>           /* never reached, but keep compiler happy */
>           retval = NULL;
>       }
> +
> +     return retval;
> + }
> +
> + /*
> +  * per_MultiFuncCall
> +  *
> +  * Do Multi-function per-call setup
> +  */
> + FuncCallContext *
> + per_MultiFuncCall(PG_FUNCTION_ARGS)
> + {
> +     FuncCallContext *retval = (FuncCallContext *) fcinfo->flinfo->fn_extra;
> +
> +     /* make sure we start with a fresh slot */
> +     if(retval->slot != NULL)
> +         ExecClearTuple(retval->slot);
>
>       return retval;
>   }
> Index: src/include/funcapi.h
> ===================================================================
> RCS file: /opt/src/cvs/pgsql/src/include/funcapi.h,v
> retrieving revision 1.2
> diff -c -r1.2 funcapi.h
> *** src/include/funcapi.h    22 Jun 2002 04:08:07 -0000    1.2
> --- src/include/funcapi.h    9 Jul 2002 18:17:27 -0000
> ***************
> *** 65,86 ****
>    */
>   typedef struct
>   {
> !     /* Number of times we've been called before */
>       uint32            call_cntr;
>
> !     /* Maximum number of calls */
>       uint32            max_calls;
>
> !     /* pointer to result slot */
>       TupleTableSlot *slot;
>
> !     /* pointer to misc context info */
> !     void           *fctx;
> !
> !     /* pointer to struct containing arrays of attribute type input metainfo */
>       AttInMetadata       *attinmeta;
>
> !     /* memory context used to initialize structure */
>       MemoryContext    fmctx;
>
>   }    FuncCallContext;
> --- 65,121 ----
>    */
>   typedef struct
>   {
> !     /*
> !      * Number of times we've been called before.
> !      *
> !      * call_cntr is initialized to 0 for you by SRF_FIRSTCALL_INIT(), and
> !      * incremented for you every time SRF_RETURN_NEXT() is called.
> !      */
>       uint32            call_cntr;
>
> !     /*
> !      * OPTIONAL maximum number of calls
> !      *
> !      * max_calls is here for convenience ONLY and setting it is OPTIONAL.
> !      * If not set, you must provide alternative means to know when the
> !      * function is done.
> !      */
>       uint32            max_calls;
>
> !     /*
> !      * OPTIONAL pointer to result slot
> !      *
> !      * slot is for use when returning tuples (i.e. composite data types)
> !      * and is not needed when returning base (i.e. scalar) data types.
> !      */
>       TupleTableSlot *slot;
>
> !     /*
> !      * OPTIONAL pointer to misc user provided context info
> !      *
> !      * user_fctx is for use as a pointer to your own struct to retain
> !      * arbitrary context information between calls for your function.
> !      */
> !     void           *user_fctx;
> !
> !     /*
> !      * OPTIONAL pointer to struct containing arrays of attribute type input
> !      * metainfo
> !      *
> !      * attinmeta is for use when returning tuples (i.e. composite data types)
> !      * and is not needed when returning base (i.e. scalar) data types. It
> !      * is ONLY needed if you intend to use BuildTupleFromCStrings() to create
> !      * the return tuple.
> !      */
>       AttInMetadata       *attinmeta;
>
> !     /*
> !      * memory context used to initialize structure
> !      *
> !      * fmctx is set by SRF_FIRSTCALL_INIT() for you, and used by
> !      * SRF_RETURN_DONE() for cleanup. It is primarily for internal use
> !      * by the API.
> !      */
>       MemoryContext    fmctx;
>
>   }    FuncCallContext;
> ***************
> *** 137,143 ****
>    *     Datum                result;
>    *     <user defined declarations>
>    *
> !  *     if(SRF_IS_FIRSTPASS())
>    *     {
>    *         <user defined code>
>    *         funcctx = SRF_FIRSTCALL_INIT();
> --- 172,178 ----
>    *     Datum                result;
>    *     <user defined declarations>
>    *
> !  *     if(SRF_IS_FIRSTCALL())
>    *     {
>    *         <user defined code>
>    *         funcctx = SRF_FIRSTCALL_INIT();
> ***************
> *** 148,154 ****
>    *         <user defined code>
>    *  }
>    *     <user defined code>
> !  *     funcctx = SRF_PERCALL_SETUP(funcctx);
>    *     <user defined code>
>    *
>    *     if (funcctx->call_cntr < funcctx->max_calls)
> --- 183,189 ----
>    *         <user defined code>
>    *  }
>    *     <user defined code>
> !  *     funcctx = SRF_PERCALL_SETUP();
>    *     <user defined code>
>    *
>    *     if (funcctx->call_cntr < funcctx->max_calls)
> ***************
> *** 167,180 ****
>
>   /* from funcapi.c */
>   extern FuncCallContext *init_MultiFuncCall(PG_FUNCTION_ARGS);
>   extern void end_MultiFuncCall(PG_FUNCTION_ARGS, FuncCallContext *funcctx);
>
> ! #define SRF_IS_FIRSTPASS() (fcinfo->flinfo->fn_extra == NULL)
>   #define SRF_FIRSTCALL_INIT() init_MultiFuncCall(fcinfo)
> ! #define SRF_PERCALL_SETUP(_funcctx) \
> !     fcinfo->flinfo->fn_extra; \
> !     if(_funcctx->slot != NULL) \
> !         ExecClearTuple(_funcctx->slot)
>   #define SRF_RETURN_NEXT(_funcctx, _result) \
>       do { \
>           ReturnSetInfo       *rsi; \
> --- 202,213 ----
>
>   /* from funcapi.c */
>   extern FuncCallContext *init_MultiFuncCall(PG_FUNCTION_ARGS);
> + extern FuncCallContext *per_MultiFuncCall(PG_FUNCTION_ARGS);
>   extern void end_MultiFuncCall(PG_FUNCTION_ARGS, FuncCallContext *funcctx);
>
> ! #define SRF_IS_FIRSTCALL() (fcinfo->flinfo->fn_extra == NULL)
>   #define SRF_FIRSTCALL_INIT() init_MultiFuncCall(fcinfo)
> ! #define SRF_PERCALL_SETUP() per_MultiFuncCall(fcinfo)
>   #define SRF_RETURN_NEXT(_funcctx, _result) \
>       do { \
>           ReturnSetInfo       *rsi; \

>
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