+MSG_error_t MSG_channel_select_from(m_channel_t channel, double max_duration,
+ int *PID)
+{
+ m_host_t h = NULL;
+ simdata_host_t h_simdata = NULL;
+ xbt_fifo_item_t item;
+ m_task_t t;
+ int first_time = 1;
+ m_process_t process = MSG_process_self();
+
+ if(PID) {
+ *PID = -1;
+ }
+
+ if(max_duration==0.0) {
+ return MSG_task_probe_from(channel);
+ } else {
+ CHECK_HOST();
+ h = MSG_host_self();
+ h_simdata = h->simdata;
+
+ DEBUG2("Probing on channel %d (%s)", channel,h->name);
+ while(!(item = xbt_fifo_getFirstItem(h->simdata->mbox[channel]))) {
+ if(max_duration>0) {
+ if(!first_time) {
+ MSG_RETURN(MSG_OK);
+ }
+ }
+ xbt_assert2(!(h_simdata->sleeping[channel]),
+ "A process (%s(%d)) is already blocked on this channel",
+ h_simdata->sleeping[channel]->name,
+ h_simdata->sleeping[channel]->simdata->PID);
+ h_simdata->sleeping[channel] = process; /* I'm waiting. Wake me up when you're ready */
+ if(max_duration>0) {
+ __MSG_process_block(max_duration);
+ } else {
+ __MSG_process_block(-1);
+ }
+ if(surf_workstation_resource->extension_public->get_state(h_simdata->host)
+ == SURF_CPU_OFF) {
+ MSG_RETURN(MSG_HOST_FAILURE);
+ }
+ h_simdata->sleeping[channel] = NULL;
+ first_time = 0;
+ }
+ if (!item || !(t = xbt_fifo_get_item_content(item))) {
+ MSG_RETURN(MSG_OK);
+ }
+ if(PID) {
+ *PID = MSG_process_get_PID(t->simdata->sender);
+ }
+ MSG_RETURN(MSG_OK);
+ }
+}