signals: cleanup chksig a little, clear mask on ignored no-op signals

diff --git a/Kernel/process.c b/Kernel/process.c
index 8d8dcd3..2ca0349 100644 (file)
--- a/Kernel/process.c
+++ b/Kernel/process.c
@@ -432,35 +432,38 @@ void sgrpsig(uint16_t pgrp, uint16_t sig)
 void chksigs(void)
 {
        uint8_t j;
+       uint32_t pending = udata.u_ptab->p_pending & ~udata.u_ptab->p_held;
+       int16_t (**svec)() = &udata.u_sigvec[0];
+       uint32_t m;
 
        // any signals pending?
-       if (!(udata.u_ptab->p_pending & ~udata.u_ptab->p_held)) {
+       if (!pending)
                return;
-       }
+
        // dispatch the lowest numbered signal
        for (j = 1; j < NSIGS; ++j) {
-               if (!
-                   (sigmask(j) & udata.u_ptab->p_pending & ~udata.u_ptab->
-                    p_held))
+               svec++;
+               m = sigmask(j);
+               if (!(m & pending))
                        continue;
                /* This is more complex than in V7 - we have multiple
                   behaviours (plus the unimplemented as yet core dump) */
-               if (udata.u_sigvec[j] == SIG_DFL) {
+               if (*svec == SIG_DFL) {
                        /* SIGCONT is subtle - we woke the process to handle
                           the signal so ignoring here works fine */
                        if (j == SIGCHLD || j == SIGURG ||
-                           j == SIGIO || j == SIGCONT)
+                           j == SIGIO || j == SIGCONT) {
+                               udata.u_ptab->p_pending &= ~m;  // unset the bit
                                continue;
+                       }
                        /* FIXME: core dump on some signals */
 #ifdef DEBUG
                        kputs("process terminated by signal: ");
 #endif
                        doexit(0, j);
-               }
-
-               if (udata.u_sigvec[j] != SIG_IGN) {
+               } else if (*svec != SIG_IGN) {
                        /* Arrange to call the user routine at return */
-                       udata.u_ptab->p_pending &= ~sigmask(j); // unset the bit
+                       udata.u_ptab->p_pending &= ~m;  // unset the bit
 #ifdef DEBUG
                        kprintf("about to process signal %d\n", j);
 #endif