Replace uses of QUEUE_FOREACH when the list can get modified while
iterating over it, in particular when a callback is made into the
user's code. This should fix a number of spurious failures that
people have been reporting.
PR-URL: https://github.com/libuv/libuv/pull/565
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
There's a data race in the consuming side of uv_async. The "pending"
flag could be trampled by producing thread causing an async send
event to be missed.
PR-URL: https://github.com/libuv/libuv/pull/189
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
Reopen one of the pipe descriptors as read/write through the procfs.
Allows us to close the original pipe file descriptors, saving a file
descriptor on kernels that don't support eventfd(2).
Ensure that close() system calls don't close stdio file descriptors
because that is almost never the intention.
This is also a partial workaround for a kernel bug that seems to affect
all Linux kernels when stdin is a pipe that gets closed: fd 0 keeps
signalling EPOLLHUP but a subsequent call to epoll_ctl(EPOLL_CTL_DEL)
fails with EBADF. See joyent/node#6271 for details and a test case.
This commit changes the libuv API to return error codes directly rather
than storing them in a loop-global field.
A code snippet like this one:
if (uv_foo(loop) < 0) {
uv_err_t err = uv_last_error(loop);
fprintf(stderr, "%s\n", uv_strerror(err));
}
Should be rewritten like this:
int err = uv_foo(loop);
if (err < 0)
fprintf(stderr, "%s\n", uv_strerror(err));
The rationale for this change is that it should make creating bindings
for other languages a lot easier: dealing with struct return values is
painful with most FFIs and often downright buggy.
`#if FOO` (where FOO is undefined) is a legal construct in C89 and C99
but gcc, clang and sparse complain loudly about it at higher warning
levels.
Squelch those warnings. Makes the code more consistent as well.
kqueue(2) on osx doesn't work (emits EINVAL error) with specific fds
(i.e. /dev/tty, /dev/null, etc). When given such descriptors - start
select(2) watcher thread that will emit io events.
This reverts commit 209abbab27.
Fixes the following SIGSEGV:
(gdb) f 1
#1 0x00007fc084683aec in uv__async_io (loop=0x7fc0848e0b40,
handle=0x7fc0848e0c78, events=1) at src/unix/async.c:175
175 ASYNC_CB(h)
(gdb) list
170
171 /* If we need to sweep all handles anyway - skip this loop */
172 if (!loop->async_sweep_needed) {
173 for (i = 0; i < end; i += sizeof(h)) {
174 h = *((uv_async_t**) (buf + i));
175 ASYNC_CB(h)
176 }
177 }
178
179 bytes -= end;
(gdb) print *h
$1 = {close_cb = 0x184e1b0, data = 0x18d9520, loop = 0x7fc0848e0b40,
type = 49, handle_queue = {prev = 0x18dae10, next = 0x7860c0}, flags = 32,
next_closing = 0x1863b40, pending = 0, async_cb = 0x31,
queue = {prev = 0x18dae50, next = 0x7860c0}}
(gdb)
It looks like the async handle gets closed or otherwise becomes invalid before
the sweep is executed.
Fixes#603.
Include missing <string.h> header. Fixes the following compiler warning:
src/unix/async.c:182:7: warning: implicit declaration of
function ‘memmove’ [-Wimplicit-function-declaration]
Fixes the following gcc 4.7+ warning:
../src/unix/internal.h:105:13: warning: always_inline function might not be
inlinable [-Wattributes]
gcc wants the always_inline function to be annotated with the 'inline' keyword
which we can't do because we compile in C89 mode.
Using __inline is not an option because that makes clang generate warnings when
-Wlanguage-extension-token is enabled.
Therefore, remove the always_inline attribute altogether and hope that the
compiler is smart enough to inline the functions.
uv_async_send would always return 1 when non-gcc compilers were used.
When uv_async_send returns 1 no attempt is made to make port_getn
return, so in this situation uv_async_send didn't wake up the event
loop.
Use atomic compare-and-swap to detect if we've been preempted by another thread
and therefore can avoid making the expensive write() syscall.
Speeds up the heavily contended case by about 1-2% and has little if any impact
on the non-contended case. I wasn't able to measure the difference at any rate.
This commit changes how the event loop determines if it needs to stay alive.
Previously, an internal counter was increased whenever a handle got created
and decreased again when the handle was closed.
While conceptually simple, it turned out hard to work with: you often want
to keep the event loop alive only if the handle is actually doing something.
Stopped or inactive handles were a frequent source of hanging event loops.
That's why this commit changes the reference counting scheme to a model where
a handle only references the event loop when it's active. 'Active' means
different things for different handle types, e.g.:
* timers: ticking
* sockets: reading, writing or listening
* processes: always active (for now, subject to change)
* idle, check, prepare: only active when started
This commit also changes how the uv_ref() and uv_unref() functions work: they
now operate on the level of individual handles, not the whole event loop.
The Windows implementation was done by Bert Belder.
