asked on

Why it show when i complie this program with rpc function?

Somebody can help me!! :-)
Why it show when i complie this program with rpc function?
server.c:19: dereferencing pointer to incomplete type!!

server.c:
#include ....

bool_t
squareproc_2_svc(square_in *inp,square_out *outp,struct svc_req *rqstp)
{
printf("thread %ld started,arg=%ld,auth=%d\n",pr_thread_id(NULL),inp->arg1,rqstp->rq_cred.oa_flavor);

if(rqstp->rq_cred.oa_flavor==AUTH_SYS)
{
struct authsys_parms *au;

au=(struct authsys_parms *)rqstp->rq_clntcred;
//#line 19
printf("AUTH_SYS:host %s,uid %ld,gid %ld\n",au->aup_machname,au->aup_uid,au->aup_gid);
}

sleep(5);

outp->res1=inp->arg1*inp->arg1;

printf("thread %ld done\n",pr_thread_id(NULL));

return(TRUE);
}

int
square_prog_2_freeresult(SVCXPRT *transp,xdrproc_t xdr_result,caddr_t result)
{
xdr_free(xdr_result,result);

return(1);
}

mail:great_liudan@hotmail.com

rfr1tz

So you think this is an easy problem? I think it's a homework problem.

However, assuming that line 19 is the printf statement, au is a pointer to an authsys_parms structure and then you point it at rqstp->rq_clntcred by type casting.

So au is pointing at rqstp->rq_clntcred.... (whatever that is.) But then you try to print out fields from au. But au is pointing at some junk (rqstp->rq_clntred) which I am sure is not a authsys_parms structure. So boom, you blow up.

By the way, I don't know who's picking your variable names (I know some are system names), but they are just awful - the code looks like it's encrypted.

ASKER CERTIFIED SOLUTION

bryanh

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bryanh

And by the way, I should mention that this is not a Linux programming question. It's a C language question.

rfr1tz

hmm, you're right bryanh, I'm wrong. As she mentions, it's a compile time problem. I was fooled by which line is line 19. I assumed it was the printf statement.

liudan

ASKER

Thank you!!
I find the reason:gcc complier can't find struct authsys_parms.

struct authsys_parms {
u_long aup_stamp;
char *aup_machinename;
uid_t aup_uid;
gid_t aup_gid;
u_int aup_len;
gid_t *aup_gids;
};

So i replace struct authsys_parms with struct authunix_parms in rpc/auth_unix.h.

/*
* Unix style credentials.
*/
struct authunix_parms
{
u_long aup_time;
char *aup_machname;
__uid_t aup_uid;
__gid_t aup_gid;
u_int aup_len;
__gid_t *aup_gids;
};

This problem is solved~~~!!!
Thank bryanh & rfr1tz!!! Without your help,I can't do it!!!