ping? is this ok? Or it is not trivial at all, and better do a normal
patch? And write it better?
I have no inconvenience on doing so, but I didn't want to duplicate patches
in the list.
El 10/02/2012 10:57, "Alex Barcelo" <abarc...@ac.upc.edu> escribió:
> // Test source and desired /real output:
>
> #include <signal.h>
> #include <unistd.h>
> #include <stdio.h>
> #include <stdlib.h>
>
> void handler(int sig)
> {
> unsigned int a;
> // to prevent uninitialized stack, normally a = 0
> if ( a>10 ) a = 0;
> a = a + 1;
> printf ("new value: %d\n" , a );
> if (a > 7) _exit(a);
> return;
> }
>
> int main()
> {
> int ret;
> char * stackA = malloc(SIGSTKSZ);
> char * stackB = malloc(SIGSTKSZ);
> stack_t ssA = {
> .ss_size = SIGSTKSZ,
> .ss_sp = stackA,
> };
> stack_t ssB = {
> .ss_size = SIGSTKSZ,
> .ss_sp = stackB,
> };
> struct sigaction sa = {
> .sa_handler = handler,
> .sa_flags = SA_ONSTACK
> };
>
> // no error checking, only debug output
> ret = sigfillset(&sa.sa_mask);
> printf ( "Sigfillset: %d\n" , ret );
> ret = sigaction(SIGUSR1, &sa, 0);
> printf ( "Sigaction: %d\n" , ret );
>
> while (1) {
> printf ("On stack A -- " );
> ret = sigaltstack(&ssA, 0);
> printf ( "sigaltstack return: %d -- " , ret );
> kill(0, SIGUSR1);
> sleep(1);
> printf (" -- " );
> kill(0, SIGUSR1);
> sleep(1);
>
> printf ("On stack B -- " );
> ret = sigaltstack(&ssB, 0);
> printf ( "sigaltstack return: %d -- " , ret );
> kill(0, SIGUSR1);
> sleep(1);
> }
> }
>
> /* Desired output:
> Sigfillset: 0
> Sigaction: 0
> On stack A -- sigaltstack return: 0 -- new value: 1
> -- new value: 2
> On stack B -- sigaltstack return: 0 -- new value: 1
> On stack A -- sigaltstack return: 0 -- new value: 3
> -- new value: 4
> On stack B -- sigaltstack return: 0 -- new value: 2
> On stack A -- sigaltstack return: 0 -- new value: 5
> -- new value: 6
> On stack B -- sigaltstack return: 0 -- new value: 3
> On stack A -- sigaltstack return: 0 -- new value: 7
> -- new value: 8
>
> Output for ppc without patch:
> Sigfillset: 0
> Sigaction: 0
> On stack A -- sigaltstack return: 0 -- new value: 1
> -- new value: 2
> On stack B -- sigaltstack return: 0 -- new value: 3 // WRONG!!
> On stack A -- sigaltstack return: 0 -- new value: 4
> -- new value: 5 // WRONG AGAIN!
> ...
> */
>
