Re: URL Managment - C Function help

It is solved. I'll propose my work the next weeks. :-)

Regards,
Samuel.

Le mercredi 21 octobre 2009 à 17:31 +0200, Samuel ROZE a écrit :
> Hi,
>
> I'm writing two functions "parse_url_key" and "parse_url_record" which
> will have one text argument and will return a record or a specific
> column of it. Theses functions are calling "parse_url_exec" which parse
> the URL. When theses function will works, i'll purpose them to
> PostgreSQL community.
>
> The problem is that they don't work fine... :/
>
> Prototypes of function/struct used by them:
> ----------------------------------------------------
> typedef struct url {
> char *scheme;
> char *user;
> char *pass;
> char *host;
> unsigned short port;
> char *path;
> char *query;
> char *fragment;
> } url;
>
> url *parse_url_exec (char* str);
> ----------------------------------------------------
>
> The parse_url_key function:
> ----------------------------------------------------
> PG_FUNCTION_INFO_V1(parse_url_key);
> Datum parse_url_key (PG_FUNCTION_ARGS)
> {
> char str[] = "http://www.ovh.com/intenal.html";
> //text *my_url = PG_GETARG_TEXT_P(0);
> //char *char_url = DatumGetCString(my_url);
>
> url *ret = parse_url_exec(str);
>
> PG_RETURN_TEXT_P(ret->host);
> }
> ----------------------------------------------------
> Note: I'm using built-in strings to be sure that the recuperation
> doesn't change anything..
>
> This function works well:
> ----------------------------------------------------
> postgres=# CREATE OR REPLACE FUNCTION parse_url_key(text) RETURNS text
> AS '/home/samuel/parse_url.so', 'parse_url_key' LANGUAGE C;
> CREATE FUNCTION
> postgres=# SELECT parse_url_key('') as scheme;
> scheme
> ------------
> ww.ovh.com
> (1 row)
> ----------------------------------------------------
> Note: there's a little problem here but not important. :-)
>
> The problem is that the other function, "parse_url_record" doesn't
> return values ! The code is:
> ----------------------------------------------------
> PG_FUNCTION_INFO_V1(parse_url_record);
> Datum parse_url_record (PG_FUNCTION_ARGS)
> {
> // Vars about the params
> //text *str2 = PG_GETARG_TEXT_P(0);
> char str[] = "http://www.ovh.com/intenal.html";
>
> // Some vars which will used to create the composite output type
> TupleDesc tupdesc;
> Datum values[2]; // 8 values
> HeapTuple tuple;
> bool nulls[2];
> int tuplen;
>
> // Check NULLs values
> if(PG_ARGISNULL(0) || PG_ARGISNULL(1)) {
> PG_RETURN_NULL();
> }
>
> url *ret = parse_url_exec(str);
>
> // Add datas into the values Datum
> values[0] = PointerGetDatum(ret->scheme);
> values[1] = PointerGetDatum(ret->host);
>
> // Convert values into a composite type
> /*tuplen = tupdesc->natts;
> nulls = palloc(tuplen * sizeof(bool));*/
> memset(nulls, 0, sizeof(nulls));
>
> // build tuple from datum array
> tuple = heap_form_tuple(tupdesc, values, nulls);
> // Free null values
> /*pfree(nulls);*/
>
> // Return the composite type
> PG_RETURN_DATUM(HeapTupleGetDatum(tuple));
> }
> ----------------------------------------------------
> Note: I'm just returning scheme and host fields for test, but others are
> too completed by parse_url_exec.
>
> It doesn't works fine:
> ----------------------------------------------------
> postgres=# CREATE OR REPLACE FUNCTION parse_url_record(text) RETURNS
> record AS '/home/samuel/parse_url.so', 'parse_url_record' LANGUAGE C;
> CREATE FUNCTION
> postgres=# SELECT * FROM parse_url_record('') as ("scheme" text, "host"
> text);
> scheme | host
> --------+------
> |
> (1 row)
> ----------------------------------------------------
>
> Is there anybody here who can help me ?
>
> Thanks you very much !
> Samuel ROZE.
> http://www.d-sites.com
>
>