r4545: Fix based on work by Derrell.Lipman@UnwiredUniverse.com :

  * In an application with signals, it was possible for functions to block
    indefinitely while awaiting timeouts.  This patch ensures that if a system
    call with a timeout is aborted and needs to be restarted, it is restarted
    with a timeout which is adjusted for the amount of time already waited.

Jeremy.

diff --git a/source/lib/select.c b/source/lib/select.c
index f88ad52de65e5ce4ac40b9dcd84ad6ff1e66a9b7..f3d119bdb153e488a41b70af359547adae7e0de4 100644 (file)
--- a/source/lib/select.c
+++ b/source/lib/select.c
@@ -128,12 +128,23 @@ int sys_select_intr(int maxfd, fd_set *readfds, fd_set *writefds, fd_set *errorf
 {
        int ret;
        fd_set *readfds2, readfds_buf, *writefds2, writefds_buf, *errorfds2, errorfds_buf;
-       struct timeval tval2, *ptval;
+       struct timeval tval2, *ptval, end_time;
 
        readfds2 = (readfds ? &readfds_buf : NULL);
        writefds2 = (writefds ? &writefds_buf : NULL);
        errorfds2 = (errorfds ? &errorfds_buf : NULL);
-       ptval = (tval ? &tval2 : NULL);
+       if (tval) {
+               GetTimeOfDay(&end_time);
+               end_time.tv_sec += tval->tv_sec;
+               end_time.tv_usec += tval->tv_usec;
+               end_time.tv_sec += end_time.tv_usec / 1000000;
+               end_time.tv_usec %= 1000000;
+               errno = 0;
+               tval2 = *tval;
+               ptval = &tval2;
+       } else {
+               ptval = NULL;
+       }
 
        do {
                if (readfds)
@@ -142,8 +153,19 @@ int sys_select_intr(int maxfd, fd_set *readfds, fd_set *writefds, fd_set *errorf
                        writefds_buf = *writefds;
                if (errorfds)
                        errorfds_buf = *errorfds;
-               if (tval)
-                       tval2 = *tval;
+               if (ptval && (errno == EINTR)) {
+                       struct timeval now_time;
+                       SMB_BIG_INT tdif;
+
+                       GetTimeOfDay(&now_time);
+                       tdif = usec_time_diff(&end_time, &now_time);
+                       if (tdif <= 0) {
+                               ret = 0; /* time expired. */
+                               break;
+                       }
+                       ptval->tv_sec = tdif / 1000000;
+                       ptval->tv_usec = tdif % 1000000;
+               }
 
                ret = sys_select(maxfd, readfds2, writefds2, errorfds2, ptval);
        } while (ret == -1 && errno == EINTR);