1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most

   changes in MD code are trivial, before this change, trapsignal and
   sendsig use discrete parameters, now they uses member fields of
   ksiginfo_t structure. For sendsig, this change allows us to pass
   POSIX realtime signal value to user code.

2. Remove cpu_thread_siginfo, it is no longer needed because we now always
   generate ksiginfo_t data and feed it to libpthread.

3. Add p_sigqueue to proc structure to hold shared signals which were
   blocked by all threads in the proc.

4. Add td_sigqueue to thread structure to hold all signals delivered to
   thread.

5. i386 and amd64 now return POSIX standard si_code, other arches will
   be fixed.

6. In this sigqueue implementation, pending signal set is kept as before,
   an extra siginfo list holds additional siginfo_t data for signals.
   kernel code uses psignal() still behavior as before, it won't be failed
   even under memory pressure, only exception is when deleting a signal,
   we should call sigqueue_delete to remove signal from sigqueue but
   not SIGDELSET. Current there is no kernel code will deliver a signal
   with additional data, so kernel should be as stable as before,
   a ksiginfo can carry more information, for example, allow signal to
   be delivered but throw away siginfo data if memory is not enough.
   SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can
   not be caught or masked.
   The sigqueue() syscall allows user code to queue a signal to target
   process, if resource is unavailable, EAGAIN will be returned as
   specification said.
   Just before thread exits, signal queue memory will be freed by
   sigqueue_flush.
   Current, all signals are allowed to be queued, not only realtime signals.

Earlier patch reviewed by: jhb, deischen
Tested on: i386, amd64

1 files changed, 6 insertions, 3 deletions

diff --git a/sys/i386/svr4/svr4_machdep.c b/sys/i386/svr4/svr4_machdep.c
index 3b731a2..cc03dee 100644
--- a/sys/i386/svr4/svr4_machdep.c
+++ b/sys/i386/svr4/svr4_machdep.c
@@ -411,11 +411,10 @@ svr4_getsiginfo(si, sig, code, addr)
  * will return to the user pc, psl.
  */
 void
-svr4_sendsig(catcher, sig, mask, code)
+svr4_sendsig(catcher, ksi, mask)
 	sig_t catcher;
-	int sig;
+	ksiginfo_t ksi;
 	sigset_t *mask;
-	u_long code;
 {
 	register struct thread *td = curthread;
 	struct proc *p = td->td_proc;
@@ -423,11 +422,15 @@ svr4_sendsig(catcher, sig, mask, code)
 	struct svr4_sigframe *fp, frame;
 	struct sigacts *psp;
 	int oonstack;
+	int sig;
+	int code;
 
 #if defined(DEBUG_SVR4)
 	printf("svr4_sendsig(%d)\n", sig);
 #endif
 	PROC_LOCK_ASSERT(p, MA_OWNED);
+	sig = ksi->ksi_signo;
+	code = ksi->ksi_trapno; /* use trap No. */
 	psp = p->p_sigacts;
 	mtx_assert(&psp->ps_mtx, MA_OWNED);