lib: mt-safe cancel, round deux

* Update pollfds copy as well as the original
* Keep array count for copy in thread_master
* Remove last remnants of POLLHUP in .events field
* Remove unused snmpcount (lolwut)
* Improve docs
* Add missing do_thread_cancel() call in thread_cancel_event()
* Change thread_fetch() to always enter poll() to avoid starving i/o
* Remember to free up cancel_req when destroying thread_master
* Fix dereference of null pointer
* Fix dead store to timeval
* Fix missing condition for condition variable :-)

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

1 files changed, 9 insertions, 5 deletions

diff --git a/lib/thread.h b/lib/thread.h
index d49d325f7..e48068b17 100644
--- a/lib/thread.h
+++ b/lib/thread.h
@@ -47,16 +47,19 @@ struct pqueue;
 
 struct fd_handler
 {
-  /* number of pfd stored in pfds */
-  nfds_t pfdcount;
-  /* number of pfd stored in pfds + number of snmp pfd */
-  nfds_t pfdcountsnmp;
-  /* number of pfd that fit in the allocated space of pfds */
+  /* number of pfd that fit in the allocated space of pfds. This is a constant
+   * and is the same for both pfds and copy. */
   nfds_t pfdsize;
+
   /* file descriptors to monitor for i/o */
   struct pollfd *pfds;
+  /* number of pollfds stored in pfds */
+  nfds_t pfdcount;
+
   /* chunk used for temp copy of pollfds */
   struct pollfd *copy;
+  /* number of pollfds stored in copy */
+  nfds_t copycount;
 };
 
 struct cancel_req {
@@ -75,6 +78,7 @@ struct thread_master
   struct thread_list ready;
   struct thread_list unuse;
   struct list *cancel_req;
+  bool canceled;
   pthread_cond_t cancel_cond;
   int io_pipe[2];
   int fd_limit;