Force usage of assert() condition when NDEBUG is defined

[lttng-tools.git] / src / common / compat / poll.c

diff --git a/src/common/compat/poll.c b/src/common/compat/poll.c
index d9acd901c0382802c136d49d9fa4a32eba22b24e..398d9d7b0582ab38178335fb18f41df5d4b23319 100644 (file)
--- a/src/common/compat/poll.c
+++ b/src/common/compat/poll.c
@@ -7,7 +7,6 @@
  */
 
 #define _LGPL_SOURCE
-#include <assert.h>
 #include <stdlib.h>
 #include <stdbool.h>
 
@@ -48,7 +47,7 @@ static int resize_poll_event(struct lttng_poll_event *events,
 {
        struct epoll_event *ptr;
 
-       assert(events);
+       LTTNG_ASSERT(events);
 
        ptr = realloc(events->events, new_size * sizeof(*ptr));
        if (ptr == NULL) {
@@ -374,7 +373,7 @@ static int resize_poll_event(struct compat_poll_event_array *array,
 {
        struct pollfd *ptr;
 
-       assert(array);
+       LTTNG_ASSERT(array);
 
        /* Refuse to resize the array more than the max size. */
        if (new_size > poll_max_size) {
@@ -408,7 +407,7 @@ static int update_current_events(struct lttng_poll_event *events)
        int ret;
        struct compat_poll_event_array *current, *wait;
 
-       assert(events);
+       LTTNG_ASSERT(events);
 
        current = &events->current;
        wait = &events->wait;
@@ -602,7 +601,7 @@ int compat_poll_del(struct lttng_poll_event *events, int fd)
        }
 
        /* No fd duplicate should be ever added into array. */
-       assert(current->nb_fd - 1 == count);
+       LTTNG_ASSERT(current->nb_fd - 1 == count);
        current->nb_fd = count;
 
        /* Resize array if needed. */
@@ -632,8 +631,7 @@ int compat_poll_wait(struct lttng_poll_event *events, int timeout,
                bool interruptible)
 {
        int ret, active_fd_count;
-       int idle_pfd_index = 0;
-       size_t i;
+       size_t pos = 0, consecutive_entries = 0, non_idle_pos;
 
        if (events == NULL || events->current.events == NULL) {
                ERR("poll wait arguments error");
@@ -668,34 +666,36 @@ int compat_poll_wait(struct lttng_poll_event *events, int timeout,
        active_fd_count = ret;
 
        /*
-        * Swap all active pollfd structs to the beginning of the
-        * array to emulate compat-epoll behaviour. This algorithm takes
-        * advantage of poll's returned value and the burst nature of active
-        * events on the file descriptors. The while loop guarantees that
-        * idle_pfd will always point to an idle fd.
+        * Move all active pollfd structs to the beginning of the
+        * array to emulate compat-epoll behaviour.
         */
        if (active_fd_count == events->wait.nb_fd) {
                goto end;
        }
-       while (idle_pfd_index < active_fd_count &&
-                       events->wait.events[idle_pfd_index].revents != 0) {
-               idle_pfd_index++;
-       }
 
-       for (i = idle_pfd_index + 1; idle_pfd_index < active_fd_count;
-                       i++) {
-               struct pollfd swap_pfd;
-               struct pollfd *idle_pfd = &events->wait.events[idle_pfd_index];
-               struct pollfd *current_pfd = &events->wait.events[i];
+       while (consecutive_entries != active_fd_count) {
+               struct pollfd *current = &events->wait.events[pos];
+               struct pollfd idle_entry;
 
-               if (idle_pfd->revents != 0) {
-                       swap_pfd = *current_pfd;
-                       *current_pfd = *idle_pfd;
-                       *idle_pfd = swap_pfd;
-                       idle_pfd_index++;
+               if (current->revents != 0) {
+                       consecutive_entries++;
+                       pos++;
+                       continue;
                }
-       }
 
+               non_idle_pos = pos;
+
+               /* Look for next non-idle entry. */
+               while (events->wait.events[++non_idle_pos].revents == 0);
+
+               /* Swap idle and non-idle entries. */
+               idle_entry = *current;
+               *current = events->wait.events[non_idle_pos];
+               events->wait.events[non_idle_pos] = idle_entry;
+
+               consecutive_entries++;
+               pos++;
+       }
 end:
        return ret;