Since we transition to a new PageDirectory on exec(), we need a matching
RangeAllocator to go with the new directory. Instead of juggling this in
Process and MemoryManager, simply attach the RangeAllocator to the
PageDirectory instead.
Fixes#61.
This gives us some leeway for WindowServer to queue up a bunch of messages
for one of its clients. Longer-term we should improve DoubleBuffer to be
able to grow dynamically in a way that gets billed to some reasonable place.
Passing this flag to recv() temporarily puts the file descriptor into
non-blocking mode.
Also implement LocalSocket::recv() as a simple forwarding to read().
can_write() was saying yes in situations where write() would overflow the
internal buffer. This patch adds a has_attached_peer() helper to make it
easier to understand what's going on in these functions.
This is not EOF, and never should have been so -- can trip up other code
when porting.
Also updates LibGUI and WindowServer which both relied on the old
behaviour (and didn't work without changes). There may be others, but I
didn't run into them with a quick inspection.
There are now two thread lists, one for runnable threads and one for non-
runnable threads. Thread::set_state() is responsible for moving threads
between the lists.
Each thread also has a back-pointer to the list it's currently in.
select essentially has 3 modes (which is presumably why we're finding it
so hard to get this right in a reliable way :)).
1. NULL timeout -- no timeout on blocking
2. non-NULL timeout that is not zero'd -- timeout on blocking
3. non-NULL but zero timeout -- no blocking at all (immediate poll)
For cases 1 and 2, we want to block the thread. We have a timeout set
only for case 2, though.
Case 3 should not block the thread, and does not have a timeout set.
The scheduler expects m_select_timeout to act as a deadline. That is, it
should contain the time that a task should wake at -- but we were
directly copying the time from userspace, which meant that it always
returned virtually immediately.
At the same time, fix CEventLoop to not rely on the broken select behavior
by subtracting the current time from the time of the nearest timer.
This makes out-of-tree linking possible. And at the same time, add a
CMakeToolchain.txt file that can be used to build arbitrary cmake-using
applications on Serenity by pointing to the CMAKE_TOOLCHAIN_FILE when
running cmake:
-DCMAKE_TOOLCHAIN_FILE=~/code/serenity/Toolchain/CMakeToolchain.txt
Based on the description I read, this syscall doesn't seem completely
reasonable, but let's at least return a number that is likely to change
between invocations in case somebody depends on that happening.
These functions were doing exactly the same thing for range allocation, so
share that code in an allocate_range() helper.
Region allocation will now also fail if range allocation fails, which means
that mmap() can actually fail without falling apart. Exciting times!
