tevent: define TEVENT_NUM_SIGNALS based on SIGRTMAX

[metze/samba/wip.git] / lib / tevent / tevent_signal.c

diff --git a/lib/tevent/tevent_signal.c b/lib/tevent/tevent_signal.c
index dbab8a8adabc489a3ae58dd8b543a3485b28a4b3..6d746fc7eccc47dc8c304603f52a8ef9b748f0c6 100644 (file)
--- a/lib/tevent/tevent_signal.c
+++ b/lib/tevent/tevent_signal.c
@@ -30,7 +30,11 @@
 #include "tevent_internal.h"
 #include "tevent_util.h"
 
+#ifdef SIGRTMAX
+#define TEVENT_NUM_SIGNALS (SIGRTMAX + 1)
+#else
 #define TEVENT_NUM_SIGNALS 64
+#endif
 
 /* maximum number of SA_SIGINFO signals to hold in the queue.
   NB. This *MUST* be a power of 2, in order for the ring buffer
@@ -82,7 +86,6 @@ static uint32_t tevent_sig_count(struct tevent_sigcounter s)
 static void tevent_common_signal_handler(int signum)
 {
        char c = 0;
-       ssize_t res;
        struct tevent_common_signal_list *sl;
        struct tevent_context *ev = NULL;
        int saved_errno = errno;
@@ -95,7 +98,7 @@ static void tevent_common_signal_handler(int signum)
                if (sl->se->event_ctx && sl->se->event_ctx != ev) {
                        ev = sl->se->event_ctx;
                        /* doesn't matter if this pipe overflows */
-                       res = write(ev->pipe_fds[1], &c, 1);
+                       (void) write(ev->pipe_fds[1], &c, 1);
                }
        }
 
@@ -180,9 +183,8 @@ static void signal_pipe_handler(struct tevent_context *ev, struct tevent_fd *fde
                                uint16_t flags, void *_private)
 {
        char c[16];
-       ssize_t res;
        /* its non-blocking, doesn't matter if we read too much */
-       res = read(fde->fd, c, sizeof(c));
+       (void) read(fde->fd, c, sizeof(c));
 }
 
 /*
@@ -309,6 +311,15 @@ struct tevent_signal *tevent_common_add_signal(struct tevent_context *ev,
        return se;
 }
 
+struct tevent_se_exists {
+       struct tevent_se_exists **myself;
+};
+
+static int tevent_se_exists_destructor(struct tevent_se_exists *s)
+{
+       *s->myself = NULL;
+       return 0;
+}
 
 /*
   check if a signal is pending
@@ -337,7 +348,25 @@ int tevent_common_check_signal(struct tevent_context *ev)
                }
                for (sl=sig_state->sig_handlers[i];sl;sl=next) {
                        struct tevent_signal *se = sl->se;
+                       struct tevent_se_exists *exists;
+
                        next = sl->next;
+
+                       /*
+                        * We have to be careful to not touch "se"
+                        * after it was deleted in its handler. Thus
+                        * we allocate a child whose destructor will
+                        * tell by nulling out itself that its parent
+                        * is gone.
+                        */
+                       exists = talloc(se, struct tevent_se_exists);
+                       if (exists == NULL) {
+                               continue;
+                       }
+                       exists->myself = &exists;
+                       talloc_set_destructor(
+                               exists, tevent_se_exists_destructor);
+
 #ifdef SA_SIGINFO
                        if (se->sa_flags & SA_SIGINFO) {
                                uint32_t j;
@@ -354,17 +383,26 @@ int tevent_common_check_signal(struct tevent_context *ev)
                                        se->handler(ev, se, i, 1,
                                                    (void*)&sig_state->sig_info[i][ofs], 
                                                    se->private_data);
+                                       if (!exists) {
+                                               break;
+                                       }
                                }
-                               if (se->sa_flags & SA_RESETHAND) {
+#ifdef SA_RESETHAND
+                               if (exists && (se->sa_flags & SA_RESETHAND)) {
                                        talloc_free(se);
                                }
+#endif
+                               talloc_free(exists);
                                continue;
                        }
 #endif
                        se->handler(ev, se, i, count, NULL, se->private_data);
-                       if (se->sa_flags & SA_RESETHAND) {
+#ifdef SA_RESETHAND
+                       if (exists && (se->sa_flags & SA_RESETHAND)) {
                                talloc_free(se);
                        }
+#endif
+                       talloc_free(exists);
                }
 
 #ifdef SA_SIGINFO