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Changed the FD selection/deselection handling a bit:

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* B_EVENT_INVALID is no longer passed to the FD's select()/deselect() hooks.
* Now we always attach the select info to the I/O context, even if no event has
  been selected. The reasoning is that B_EVENT_INVALID is always automatically
  selected and handled by the VFS, so we need the handle to notify on close().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32417 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Ingo Weinhold 2009-08-15 16:28:15 +00:00
parent 5ce6cb5c32
commit 57dc0e2a53
1 changed files with 37 additions and 41 deletions
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78
src/system/kernel/fs/fd.cpp
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@ -1,4 +1,5 @@
/*
* Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
* Copyright 2002-2009, Axel Dörfler, axeld@pinc-software.de.
* Distributed under the terms of the MIT License.
*/
@ -522,9 +523,10 @@ deselect_select_infos(file_descriptor* descriptor, select_info* infos)
select_sync* sync = info->sync;
// deselect the selected events
if (descriptor->ops->fd_deselect && info->selected_events) {
uint16 eventsToDeselect = info->selected_events & ~B_EVENT_INVALID;
if (descriptor->ops->fd_deselect != NULL && eventsToDeselect != 0) {
for (uint16 event = 1; event < 16; event++) {
if (info->selected_events & SELECT_FLAG(event)) {
if ((eventsToDeselect & SELECT_FLAG(event)) != 0) {
descriptor->ops->fd_deselect(descriptor, event,
(selectsync*)info);
}
@ -554,13 +556,12 @@ select_fd(int32 fd, struct select_info* info, bool kernel)
if (descriptor == NULL)
return B_FILE_ERROR;
if (info->selected_events == 0)
return B_OK;
uint16 eventsToSelect = info->selected_events & ~B_EVENT_INVALID;
if (!descriptor->ops->fd_select) {
if (descriptor->ops->fd_select == NULL && eventsToSelect != 0) {
// if the I/O subsystem doesn't support select(), we will
// immediately notify the select call
return notify_select_events(info, info->selected_events);
return notify_select_events(info, eventsToSelect);
}
// We need the FD to stay open while we're doing this, so no select()/
@ -573,46 +574,43 @@ select_fd(int32 fd, struct select_info* info, bool kernel)
uint32 selectedEvents = 0;
for (uint16 event = 1; event < 16; event++) {
if (info->selected_events & SELECT_FLAG(event)
if ((eventsToSelect & SELECT_FLAG(event)) != 0
&& descriptor->ops->fd_select(descriptor, event,
(selectsync*)info) == B_OK) {
selectedEvents |= SELECT_FLAG(event);
}
}
info->selected_events = selectedEvents;
info->selected_events = selectedEvents
| (info->selected_events & B_EVENT_INVALID);
// If any event has been selected, add the info to the IO context.
if (selectedEvents != 0) {
locker.Lock();
if (context->fds[fd] != descriptor) {
// Someone close()d the index in the meantime. deselect() all
// events.
info->next = NULL;
deselect_select_infos(descriptor, info);
// Add the info to the IO context. Even if nothing has been selected -- we
// always support B_EVENT_INVALID.
locker.Lock();
if (context->fds[fd] != descriptor) {
// Someone close()d the index in the meantime. deselect() all
// events.
info->next = NULL;
deselect_select_infos(descriptor, info);
// Release our open reference of the descriptor.
close_fd(descriptor);
return B_FILE_ERROR;
}
// The FD index hasn't changed, so we add the select info to the table.
info->next = context->select_infos[fd];
context->select_infos[fd] = info;
// As long as the info is in the list, we keep a reference to the sync
// object.
atomic_add(&info->sync->ref_count, 1);
// Finally release our open reference. It is safe just to decrement,
// since as long as the descriptor is associated with the slot,
// someone else still has it open.
atomic_add(&descriptor->open_count, -1);
} else {
// Release our open reference.
// Release our open reference of the descriptor.
close_fd(descriptor);
return B_FILE_ERROR;
}
// The FD index hasn't changed, so we add the select info to the table.
info->next = context->select_infos[fd];
context->select_infos[fd] = info;
// As long as the info is in the list, we keep a reference to the sync
// object.
atomic_add(&info->sync->ref_count, 1);
// Finally release our open reference. It is safe just to decrement,
// since as long as the descriptor is associated with the slot,
// someone else still has it open.
atomic_add(&descriptor->open_count, -1);
return B_OK;
}
@ -623,9 +621,6 @@ deselect_fd(int32 fd, struct select_info* info, bool kernel)
TRACE(("deselect_fd(fd = %ld, info = %p (%p), 0x%x)\n", fd, info,
info->sync, info->selected_events));
if (info->selected_events == 0)
return B_OK;
FDGetter fdGetter;
// define before the context locker, so it will be destroyed after it
@ -651,9 +646,10 @@ deselect_fd(int32 fd, struct select_info* info, bool kernel)
locker.Unlock();
// deselect the selected events
if (descriptor->ops->fd_deselect && info->selected_events) {
uint16 eventsToDeselect = info->selected_events & ~B_EVENT_INVALID;
if (descriptor->ops->fd_deselect != NULL && eventsToDeselect != 0) {
for (uint16 event = 1; event < 16; event++) {
if (info->selected_events & SELECT_FLAG(event)) {
if ((eventsToDeselect & SELECT_FLAG(event)) != 0) {
descriptor->ops->fd_deselect(descriptor, event,
(selectsync*)info);
}