69 lines
1.9 KiB
C
69 lines
1.9 KiB
C
/* The kernel call that is implemented in this file:
|
|
* m_type: SYS_SIGRETURN
|
|
*
|
|
* The parameters for this kernel call are:
|
|
* m2_i1: SIG_ENDPT # process returning from handler
|
|
* m2_p1: SIG_CTXT_PTR # pointer to sigcontext structure
|
|
*
|
|
*/
|
|
|
|
#include "../system.h"
|
|
#include <string.h>
|
|
#include <ibm/cpu.h>
|
|
#include <sys/sigcontext.h>
|
|
|
|
#if USE_SIGRETURN
|
|
|
|
/*===========================================================================*
|
|
* do_sigreturn *
|
|
*===========================================================================*/
|
|
PUBLIC int do_sigreturn(m_ptr)
|
|
message *m_ptr; /* pointer to request message */
|
|
{
|
|
/* POSIX style signals require sys_sigreturn to put things in order before
|
|
* the signalled process can resume execution
|
|
*/
|
|
struct sigcontext sc;
|
|
register struct proc *rp;
|
|
int proc_nr, r;
|
|
|
|
if (! isokendpt(m_ptr->SIG_ENDPT, &proc_nr)) return(EINVAL);
|
|
if (iskerneln(proc_nr)) return(EPERM);
|
|
rp = proc_addr(proc_nr);
|
|
|
|
/* Copy in the sigcontext structure. */
|
|
if((r=data_copy(m_ptr->SIG_ENDPT, (vir_bytes) m_ptr->SIG_CTXT_PTR,
|
|
SYSTEM, (vir_bytes) &sc, sizeof(struct sigcontext))) != OK)
|
|
return r;
|
|
|
|
/* Restore user bits of psw from sc, maintain system bits from proc. */
|
|
sc.sc_psw = (sc.sc_psw & X86_FLAGS_USER) |
|
|
(rp->p_reg.psw & ~X86_FLAGS_USER);
|
|
|
|
#if (_MINIX_CHIP == _CHIP_INTEL)
|
|
/* Don't panic kernel if user gave bad selectors. */
|
|
sc.sc_cs = rp->p_reg.cs;
|
|
sc.sc_ds = rp->p_reg.ds;
|
|
sc.sc_es = rp->p_reg.es;
|
|
sc.sc_ss = rp->p_reg.ss;
|
|
#if _WORD_SIZE == 4
|
|
sc.sc_fs = rp->p_reg.fs;
|
|
sc.sc_gs = rp->p_reg.gs;
|
|
#endif
|
|
#endif
|
|
|
|
/* Restore the registers. */
|
|
memcpy(&rp->p_reg, &sc.sc_regs, sizeof(sigregs));
|
|
#if (_MINIX_CHIP == _CHIP_INTEL)
|
|
if(sc.sc_flags & MF_FPU_INITIALIZED)
|
|
{
|
|
memcpy(rp->p_fpu_state.fpu_save_area_p, &sc.sc_fpu_state,
|
|
FPU_XFP_SIZE);
|
|
rp->p_misc_flags |= MF_FPU_INITIALIZED; /* Restore math usage flag. */
|
|
}
|
|
#endif
|
|
|
|
return(OK);
|
|
}
|
|
#endif /* USE_SIGRETURN */
|
|
|