local nextMutexID = 0

function syscalls.lockmutex(process, thread, mtx)

expect(1, mtx, "table")

while (mtx.owner ~= nil and mtx.owner ~= thread.id) or (mtx.pid ~= nil and mtx.pid ~= process.id) do coroutine.yield() end

if mtx.owner then

if type(mtx.recursive) == "number" then

mtx.recursive = mtx.recursive + 1

return

else error("cannot recursively lock mutex", 0) end

end

mtx.owner = thread.id

mtx.pid = process.id

if mtx.recursive then mtx.recursive = 1 end

end

function syscalls.__timeout_check(process, thread, info)

if info.timeout then return false end

return syscalls[info.call](process, thread, info.object, 0)

end

function syscalls.timelockmutex(process, thread, mtx, timeout)

expect(1, mtx, "table")

expect(2, timeout, "number")

if mtx.owner then

if mtx.owner ~= thread.id then

local timer = os.startTimer(timeout)

local info = {object = mtx, timeout = false, call = "timelockmutex"}

thread.filter = function(process, thread, ev)

if ev[1] == "timer" and ev[2].id == timer then

info.timeout = true

return true

end

return mtx.owner == nil or mtx.owner == thread.id

end

return kSyscallYield, "__timeout_check", info

elseif type(mtx.recursive) == "number" then

mtx.recursive = mtx.recursive + 1

else error("cannot recursively lock mutex", 0) end

else

mtx.owner = thread.id

if mtx.recursive then mtx.recursive = 1 end

end

return true

end

function syscalls.unlockmutex(process, thread, mtx)

expect(1, mtx, "table")

if mtx.owner == thread.id and mtx.pid == process.id then

if type(mtx.recursive) == "number" then

mtx.recursive = mtx.recursive - 1

if mtx.recursive <= 0 then mtx.owner = nil end

else mtx.owner, mtx.pid = nil end

elseif mtx.owner == nil then error("mutex already unlocked", 0)

else error("mutex not locked by current thread") end

end

function syscalls.trylockmutex(process, thread, mtx)

expect(1, mtx, "table")

if mtx.owner then

if mtx.owner ~= thread.id or mtx.pid ~= process.id then

return false

elseif type(mtx.recursive) == "number" then

mtx.recursive = mtx.recursive + 1

return true

else error("cannot recursively lock mutex", 0) end

else

mtx.owner = thread.id

mtx.pid = process.id

if mtx.recursive then mtx.recursive = 1 end

return true

end

end

function syscalls.acquiresemaphore(process, thread, sem)

expect(1, sem, "table")

expect.field(sem, "count", "number")

while sem.count <= 0 do coroutine.yield() end

sem.count = sem.count - 1

end

function syscalls.timeacquiresemaphore(process, thread, sem, timeout)

expect(1, sem, "table")

expect.field(sem, "count", "number")

expect(2, timeout, "number")

if sem.count <= 0 then

local timer = os.startTimer(timeout)

local info = {object = sem, timeout = false, call = "timeacquiresemaphore"}

thread.filter = function(process, thread, ev)

if ev[1] == "timer" and ev[2].id == timer then

info.timeout = true

return true

end

return type(sem.count) ~= "number" or sem.count > 0

end

return kSyscallYield, "__timeout_check", info

end

sem.count = sem.count - 1

return true

end

function syscalls.releasesemaphore(process, thread, sem)

expect(1, sem, "table")

expect.field(sem, "count", "number")

sem.count = sem.count + 1

end