Thread: Re: [COMMITTERS]

Re: [COMMITTERS]

From
Emanuel Calvo Franco
Date:
2009/4/6 eehab hamzeh <eehab40@hotmail.com>:
>     Hello
>
> I am trying to build some functions using C language. these functions are
> mentioned in the postgresql documentation.
>
> http://www.postgresql.org/docs/8.3/interactive/xfunc-c.html
>
> Datum
> add_one_float8(PG_FUNCTION_ARGS)
> {
>     /* The macros for FLOAT8 hide its pass-by-reference nature. */
>     float8   arg = PG_GETARG_FLOAT8(0);
>
>     PG_RETURN_FLOAT8(arg + 1.0);
> }
>
> PG_FUNCTION_INFO_V1(makepoint);
>
> Datum
> makepoint(PG_FUNCTION_ARGS)
> {
>     /* Here, the pass-by-reference nature of Point is not hidden. */
>     Point     *pointx = PG_GETARG_POINT_P(0);
>     Point     *pointy = PG_GETARG_POINT_P(1);
>     Point     *new_point = (Point *) palloc(sizeof(Point));
>
>     new_point->x = pointx->x;
>     new_point->y = pointy->y;
>
>     PG_RETURN_POINT_P(new_
>  point);
> }
>
> the only function that are work are the one with int32 variable.
> the other function bring errors and are not working
> any body can give directions
>
>
> kind regards
> ihab

Re-send to pgsql-general.

Can you paste these errors and how you're compiling this?

--
      Emanuel Calvo Franco
        Sumate al ARPUG !
      (www.postgres-arg.org -
         www.arpug.com.ar)
    ArPUG / AOSUG Member
   Postgresql Support & Admin

Re: [COMMITTERS]

From
Emanuel Calvo Franco
Date:
2009/4/6 eehab hamzeh <eehab40@hotmail.com>:
> here are the code and the error , i compile them using vc++ 6 and VC++ 2008
> and minGW the example below are for minGW
> THANKS
>
> #include "postgres.h"
> #include <string.h>
> #include "fmgr.h"
>
> #ifdef PG_MODULE_MAGIC
> PG_MODULE_MAGIC;
> #endif
>
> /* by value */
>
> PG_FUNCTION_INFO_V1(add_one);
>
> Datum
> add_one(PG_FUNCTION_ARGS)
> {
>     int32   arg = PG_GETARG_INT32(0);
>
>     PG_RETURN_INT32(arg + 1);
> }
>
> /* by reference, fixed length */
>
> PG_FUNCTION_INFO_V1(add_one_float8);
>
> Datum
> add_one_float8(PG_FUNCTION_ARGS)
> {
>     /* The macros for FLOAT8 hide its pass-by-reference nature. */
>     float8   arg = PG_GETARG_FLOAT8(0);
>
>     PG_RETURN_FLOAT8(arg + 1.0);
> }
>
> PG_FUNCTION_INFO_V1(makepoint);
>
> Datum
> makepoint(PG_FUNCTION_ARGS)
> {
>     /* Here, the pass-by-reference nature of Point is not hidden. */
>     Point     *pointx = PG_GETARG_POINT_P(0);
>     Point     *pointy = PG_GETARG_POINT_P(1);
>     Point     *new_point = (Point *) palloc(sizeof(Point));
>
>     new_point->x = pointx->x;
>     new_point->y = pointy->y;
>
>     PG_RETURN_POINT_P(new_point);
> }
>
> /* by reference, variable length */
>
> PG_FUNCTION_INFO_V1(copytext);
>
> Datum
> copytext(PG_FUNCTION_ARGS)
> {
>     text     *t = PG_GETARG_TEXT_P(0);
>     /*
>      * VARSIZE is the total size of the struct in bytes.
>      */
>     text     *new_t = (text *) palloc(VARSIZE(t));
>     VARATT_SIZEP(new_t) = VARSIZE(t);
>     /*
>      * VARDATA is a pointer to the data region of the struct.
>      */
>     memcpy((void *) VARDATA(new_t), /* destination */
>            (void *) VARDATA(t),     /* source */
>            VARSIZE(t)-VARHDRSZ);    /* how many bytes */
>     PG_RETURN_TEXT_P(new_t);
> }
>
> PG_FUNCTION_INFO_V1(concat_text);
>
> Datum
> concat_text(PG_FUNCTION_ARGS)
> {
>     text  *arg1 = PG_GETARG_TEXT_P(0);
>     text  *arg2 = PG_GETARG_TEXT_P(1);
>     int32 new_text_size = VARSIZE(arg1) + VARSIZE(arg2) - VARHDRSZ;
>     text *new_text = (text *) palloc(new_text_size);
>
>     VARATT_SIZEP(new_text) = new_text_size;
>     memcpy(VARDATA(new_text), VARDATA(arg1), VARSIZE(arg1)-VARHDRSZ);
>     memcpy(VARDATA(new_text) + (VARSIZE(arg1)-VARHDRSZ),
>            VARDATA(arg2), VARSIZE(arg2)-VARHDRSZ);
>     PG_RETURN_TEXT_P(new_text);
> }
>
>
> the error
>
> in function 'makepoint':
> error: 'Point' undeclared (first use in this function)
> error: (each undeclared identifier is reported only one
> error: for each function it appears in.)
> error: 'pointx' undeclared (first use in ´this function)
> error: 'pointy' undeclared (first use in his fnction)
> error 'new_point' undeclared (first use in his function)
> error: syntax error befre ')' oken
> in function 'copy text':
> error: 'invalid lvalue in assinment
> In function 'concat_text'
> error: invalid lvalue in assignement
> warning no new line at end of file
>
> Please any direction of how to solve the problem
>
> thanks
>
>

You aren't including the path of the libs when you compiling (option -I).

don't send to comitters please, send into pgsql-general.

Thanks.


--
      Emanuel Calvo Franco
        Sumate al ARPUG !
      (www.postgres-arg.org -
         www.arpug.com.ar)
    ArPUG / AOSUG Member
   Postgresql Support & Admin

compiling c function using MinGW

From
eehab hamzeh
Date:
this is how i write the command in MinGW any more direction about I. I am a new user for MinGW
gcc -shared -o hamzeh.dll tt1.o -L "c:/programme/postgresql/8.3/lib" -lpostgres

Thanks

Ihab



>
> 2009/4/6 eehab hamzeh <eehab40@hotmail.com>:
> >     Hello
> >
> > I am trying to build some functions using C language. these functions are
> > mentioned in the postgresql documentation.
> >
> > http://www.postgresql.org/docs/8.3/interactive/xfunc-c.html
> >
> > Datum
> > add_one_float8(PG_FUNCTION_ARGS)
> > {
> > /* The macros for FLOAT8 hide its pass-by-reference nature. */
> > float8 arg = PG_GETARG_FLOAT8(0);
> >
> > PG_RETURN_FLOAT8(arg + 1.0);
> > }
> >
> > PG_FUNCTION_INFO_V1(makepoint);
> >
&g t; > Datum
> > makepoint(PG_FUNCTION_ARGS)
> > {
> > /* Here, the pass-by-reference nature of Point is not hidden. */
> > Point *pointx = PG_GETARG_POINT_P(0);
> > Point *pointy = PG_GETARG_POINT_P(1);
> > Point *new_point = (Point *) palloc(sizeof(Point));
> >
> > new_point->x = pointx->x;
> > new_point->y = pointy->y;
> >
> > PG_RETURN_POINT_P(new_
> > point);
> > }
> >
> > the only function that are work are the one with int32 variable.
> > the other function bring errors and are not working
> > any body can give directions
> >
> >
> > kind regards
> > ihab
>
> Re-send to pgsql-general.
>
> Can you paste these errors and how you're compiling this?
>
> --
> Emanuel Calvo Franco
> Sumate al ARPUG !
> (www.postgres-arg.org -
> www.arpug.com.ar)
> ArPUG / AOSUG Member
> Postgresql Support & Admin


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writing c functions for postgres

From
eehab hamzeh
Date:

Dear Sir

I am trying to build some functions using C language. these functions are
mentioned in the postgresql documentation.

.ExternalClass .EC_hmmessage P {padding:0px;} .ExternalClass body.EC_hmmessage {font-size:10pt;font-family:Ve>> I am trying to build some functions using C language. these functions a the only function that are work are the one with int32 variable.
the other function bring errors and are not working
any body can give directions

here are the code and the error , i compile them using vc++ 6 and VC++ 2008 and minGW the example below are for minGW

THANKS

#include "postgres.h"
#include <string.h>
#include "fmgr.h"

#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif

/* by value */

PG_FUNCTION_INFO_V1(add_one);
         
Datum
add_one(PG_FUNCTION_ARGS)
{
    int32   arg = PG_GETARG_INT32(0);

    PG_RETURN_INT32(arg + 1);
}

/* by reference, fixed length */

PG_FUNCTION_INFO_V1(add_one_float8);

Datum
add_one_float8(PG_FUNCTION_ARGS)
{
    /* The macros for FLOAT8 hide its pass-by-reference nature. */
    float8   arg = PG_GETARG_FLOAT8(0);

    PG_RETURN_FLOAT8(arg + 1.0);
}

PG_FUNCTION_INFO_V1(makepoint);

Datum
makepoint(PG_FUNCTION_ARGS)
{
    /* Here, the pass-by-reference nature of Point is not hidden. */
    Point     *pointx = PG_GETARG_POINT_P(0);
    Point     *pointy = PG_GETARG_POINT_P(1);
    Point     *new_point = (Point *) palloc(sizeof(Point));

  ;   new_point->x = pointx->x;
    new_point->y = pointy->y;
       
    PG_RETURN_POINT_P(new_point);
}

/* by reference, variable length */

PG_FUNCTION_INFO_V1(copytext);

Datum
copytext(PG_FUNCTION_ARGS)
{
    text     *t = PG_GETARG_TEXT_P(0);
    /*
     * VARSIZE is the total size of the struct in bytes.
     */
    text     *new_t = (text *) palloc(VARSIZE(t));
    VARATT_SIZEP(new_t) = VARSIZE(t);
    /*
     * VARDATA is a pointer to the data region of the struct.
     */ < /span>
    memcpy((void *) VARDATA(new_t), /* destination */
           (void *) VARDATA(t),     /* source */
           VARSIZE(t)-VARHDRSZ);    /* how many bytes */
    PG_RETURN_TEXT_P(new_t);
}

PG_FUNCTION_INFO_V1(concat_text);

Datum
concat_text(PG_FUNCTION_ARGS)
{
    text  *arg1 = PG_GETARG_TEXT_P(0);
    text  *arg2 = PG_GETARG_TEXT_P(1);
    int32 new_text_size = VARSIZE(arg1) + VARSIZE(arg2) - VARHDRSZ;
    text *new_text = (text *) palloc(new_text_size);

    VARATT_SIZEP(new_text) = new_text_size;
    memcpy(VARDATA(new_text), VARDATA(arg1), VA RSIZE(arg1)-VARHDRSZ);
    memcpy(VARDATA(new_text) + (VARSIZE(arg1)-VARHDRSZ),
           VARDATA(arg2), VARSIZE(arg2)-VARHDRSZ);
    PG_RETURN_TEXT_P(new_text);
}


the error

in function 'makepoint':
error: 'Point' undeclared (first use in this function)
error: (each undeclared identifier is reported only one
error: for each function it appears in.)
error: 'pointx' undeclared (first use in ´this function)
error: 'pointy' undeclared (first use in his fnction)
error 'new_point' undeclared (first use in his function)
error: syntax error befre ')' oken
in function 'copy text':
error: 'invalid lvalue in assinment
In function 'concat_text'
error: invalid lvalue in assignement

warning no new line at end of file

Please any direction of how to solve the problem

here is the command i wrote in MinGW

gcc -shared -o hamzeh.dll tt1.o -L "c:/programme/postgresql/8.3/lib" -lpostgres

thanks





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Re: writing c functions for postgres

From
"Albe Laurenz"
Date:
eehab hamzeh wrote:
> I am trying to build some functions using C language. these functions are
> mentioned in the postgresql documentation.
>
> the only function that are work are the one with int32 variable.
> the other function bring errors and are not working
> any body can give directions
>
> #include "postgres.h"
> #include <string.h>
> #include "fmgr.h"
>
> #ifdef PG_MODULE_MAGIC
> PG_MODULE_MAGIC;
> #endif
>
[...]
>
> PG_FUNCTION_INFO_V1(makepoint);
>
> Datum
> makepoint(PG_FUNCTION_ARGS)
> {
>     /* Here, the pass-by-reference nature of Point is not hidden. */
>     Point     *pointx = PG_GETARG_POINT_P(0);
>     Point     *pointy = PG_GETARG_POINT_P(1);
>     Point     *new_point = (Point *) palloc(sizeof(Point));
>
[...]
>
> PG_FUNCTION_INFO_V1(copytext);
>
> Datum
> copytext(PG_FUNCTION_ARGS)
> {
[...]
>     VARATT_SIZEP(new_t) = VARSIZE(t);
[...]
> }
>
> PG_FUNCTION_INFO_V1(concat_text);
>
> Datum
> concat_text(PG_FUNCTION_ARGS)
> {
[...]
>     VARATT_SIZEP(new_text) = new_text_size;
[...]
> }
>
>
> the error
>
> in function 'makepoint':
> error: 'Point' undeclared (first use in this function)
> error: (each undeclared identifier is reported only one
> error: for each function it appears in.)
> error: 'pointx' undeclared (first use in ´this function)
> error: 'pointy' undeclared (first use in his fnction)
> error 'new_point' undeclared (first use in his function)
> error: syntax error befre ')' oken
> in function 'copy text':
> error: 'invalid lvalue in assinment
> In function 'concat_text'
> error: invalid lvalue in assignement
> warning no new line at end of file

These error messages are certainly not what you saw on the screen.
It is best to copy and paste error messages!

If you want to have Point, you'll have to
#include "utils/geo_decls.h"

The "invalid lvalue" errors are generated because gcc does not
know VARATT_SIZEP and assumes it is a function returning int.
I recommend that you always use gcc with -Wall to see warnings!

I can find no VARATT_SIZEP in the PostgreSQL 8.3 headers.
Where did you get that from?

Yours,
Laurenz Albe

Re: writing c functions for postgres

From
Glyn Astill
Date:



--- On Tue, 7/4/09, Albe Laurenz <laurenz.albe@wien.gv.at> wrote:

> I can find no VARATT_SIZEP in the PostgreSQL 8.3 headers.
> Where did you get that from?
>
> Yours,
> Laurenz Albe
>

I think it's depreciated and he should be using SET_VARSIZE instead ...