minix/kernel/system/do_sigsend.c
Ben Gras c078ec0331 Basic VM and other minor improvements.
Not complete, probably not fully debugged or optimized.
2008-11-19 12:26:10 +00:00

107 lines
3.3 KiB
C

/* The kernel call that is implemented in this file:
* m_type: SYS_SIGSEND
*
* The parameters for this kernel call are:
* m2_i1: SIG_ENDPT # process to call signal handler
* m2_p1: SIG_CTXT_PTR # pointer to sigcontext structure
* m2_i3: SIG_FLAGS # flags for S_SIGRETURN call
*
*/
#include "../system.h"
#include <signal.h>
#include <string.h>
#include <sys/sigcontext.h>
#if USE_SIGSEND
/*===========================================================================*
* do_sigsend *
*===========================================================================*/
PUBLIC int do_sigsend(m_ptr)
message *m_ptr; /* pointer to request message */
{
/* Handle sys_sigsend, POSIX-style signal handling. */
struct sigmsg smsg;
register struct proc *rp;
struct sigcontext sc, *scp;
struct sigframe fr, *frp;
int proc, r;
if (!isokendpt(m_ptr->SIG_ENDPT, &proc)) return(EINVAL);
if (iskerneln(proc)) return(EPERM);
rp = proc_addr(proc);
/* Get the sigmsg structure into our address space. */
if((r=data_copy(PM_PROC_NR, (vir_bytes) m_ptr->SIG_CTXT_PTR,
SYSTEM, (vir_bytes) &smsg, (phys_bytes) sizeof(struct sigmsg))) != OK)
return r;
/* Compute the user stack pointer where sigcontext will be stored. */
scp = (struct sigcontext *) smsg.sm_stkptr - 1;
/* Copy the registers to the sigcontext structure. */
memcpy(&sc.sc_regs, (char *) &rp->p_reg, sizeof(struct sigregs));
#ifdef POWERPC
memcpy(&sc.sc_regs, (char *) &rp->p_reg, struct(stackframe_s));
#else
memcpy(&sc.sc_regs, (char *) &rp->p_reg, sizeof(struct sigregs));
#endif
/* Finish the sigcontext initialization. */
sc.sc_flags = 0; /* unused at this time */
sc.sc_mask = smsg.sm_mask;
/* Copy the sigcontext structure to the user's stack. */
if((r=data_copy(SYSTEM, (vir_bytes) &sc, m_ptr->SIG_ENDPT, (vir_bytes) scp,
(vir_bytes) sizeof(struct sigcontext))) != OK)
return r;
/* Initialize the sigframe structure. */
frp = (struct sigframe *) scp - 1;
fr.sf_scpcopy = scp;
fr.sf_retadr2= (void (*)()) rp->p_reg.pc;
fr.sf_fp = rp->p_reg.fp;
rp->p_reg.fp = (reg_t) &frp->sf_fp;
fr.sf_scp = scp;
fr.sf_code = 0; /* XXX - should be used for type of FP exception */
fr.sf_signo = smsg.sm_signo;
fr.sf_retadr = (void (*)()) smsg.sm_sigreturn;
/* Copy the sigframe structure to the user's stack. */
if((r=data_copy(SYSTEM, (vir_bytes) &fr, m_ptr->SIG_ENDPT, (vir_bytes) frp,
(vir_bytes) sizeof(struct sigframe))) != OK)
return r;
#if ( _MINIX_CHIP == _CHIP_POWERPC ) /* stuff that can't be done in the assembler code. */
/* When the signal handlers C code is called it will write this value
* into the signal frame (over the sf_retadr value).
*/
rp->p_reg.lr = smsg.sm_sigreturn;
/* The first (and only) parameter for the user signal handler function.
*/
rp->p_reg.retreg = smsg.sm_signo; /* note the retreg == first argument */
#endif
/* Reset user registers to execute the signal handler. */
rp->p_reg.sp = (reg_t) frp;
rp->p_reg.pc = (reg_t) smsg.sm_sighandler;
/* Reschedule if necessary. */
if(RTS_ISSET(rp, NO_PRIORITY))
RTS_LOCK_UNSET(rp, NO_PRIORITY);
else {
struct proc *caller;
caller = proc_addr(who_p);
kprintf("system: warning: sigsend a running process\n");
kprintf("caller stack: ");
proc_stacktrace(caller);
}
return(OK);
}
#endif /* USE_SIGSEND */