Added the uv_loop_fork() API that must be called in a child process to
continue using an existing loop. Internally this calls a uv__io_fork
function for each supported platform, similar to the way
uv__platform_loop_init works.
After this call, existing and new IO, async and signal watchers will
contiue working as before on all platforms, as will the
threadpool (although any threads it was using are of course gone).
On Linux and BSDs that use kqueue, existing and new fsevent watchers
will also continue to work as expected. On OS X, though, directory
fsevents will not be able to use the optimized CoreFoundation path if
they had already been used in the parent process, instead falling back
to the kqueue path used on other BSDs.
Existing fsevent watchers will not function on AIX or SunOS. This
could be relatively easily fixed by someone with AIX knowledge in the
future, but SunOS will require some additional work to keep track if
the watchers.
A new test file, test/test-fork.c, was added to contain fork-related
tests to verify functionality in the child process.
PR-URL: https://github.com/libuv/libuv/pull/846
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
Remove the unused `nevents` parameter from `uv__async_event()`
and remove the indirection of having a separate `uv__async`
type. There is only one instance per event loop these days.
This incidentally removes the `assert(n == sizeof(val))` in a
Linux-specific code path that some users seem to hit from time
to time. The cause is not well-understood and I've never been
able to reproduce it myself. Presumably libuv gets an EAGAIN
when trying to read from the eventfd but when and why that
happens is unclear.
Since the byte count is unused, removing the assert seems safe.
Worst case, libuv sometimes iterates over the async watcher list
when it doesn't have to.
Fixes: https://github.com/libuv/libuv/issues/1171
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
Supersedes: https://github.com/libuv/libuv/pull/1214
Libuv leaves loop->data unchanged in uv_loop_init() and uv_loop_done()
on Windows but it clobbered it on UNIX platforms. This commit fixes
that inconsistency.
PR-URL: https://github.com/libuv/libuv/pull/951
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
Makes uv_loop_init return an error code instead of aborting.
Currently uv_loop_init aborts if there are insufficient resources
available. As a user I want to be able to check the return code from
uv_loop_init and decide how I respond rather than having my process die.
PR-URL: https://github.com/libuv/libuv/pull/405
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
With uv_replace_allocator, it's possible to override the default
memory allocator's malloc and free calls with functions of the user's
choosing. This allows libuv to interoperate with projects requiring a
custom memory allocator.
Internally, all calls to malloc and free have been replaced with
uv__malloc and uv__free, respectively. The uv__malloc and uv__free
functions call malloc and free unless they have been overridden by a
previous call to uv_replace_allocator.
As part of this change, the special aligned memory allocations
performed in src/win/fs-event.c have been replaced with standard
allocations. The 4-byte alignment being requested in this file was
unnecessary, since standard allocators already guarantee at least an
8-byte alignment.
PR-URL: https://github.com/libuv/libuv/pull/231
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
These functions supersede uv_loop_new and uv_loop_delete.
uv_loop_init initialized a user allocated loop and uv_loop_close
removes all associated resources a loop uses after it has finished
execution.
uv_loop_new and uv_loop_delete are now deprecated.
Replace the red-black tree with a heap. The most common operation that
libuv performs on timers is looking up the first timer to expire. With
a red-black tree, that operation is O(log n). With a heap, it's O(1).
Every file descriptor opened using libuv should be automatically marked
as CLOEXEC to prevent it from leaking to a child process. Note that
since we are opening fds in a thread pool, there is a possible race
condition between `uv_spawn()` and the `open()` + `uv__cloexec()`. The
rwlock was added to avoid it.
see https://github.com/joyent/node/issues/6905
On some systems, clock_gettime(CLOCK_MONOTONIC) is only serviced from
the vDSO when the __vdso_clock_gettime() wrapper is confident enough
that the vDSO timestamp is highly accurate. When in doubt, it falls
back to making a traditional SYS_clock_gettime system call with all
the overhead that entails.
While a commendable approach, it's overkill for our purposes because we
don't usually need high precision time. That's why this commit switches
to CLOCK_MONOTONIC_COARSE for low-precision timekeeping, provided said
clock has at least a one millisecond resolution.
This change should eliminate the system call on almost all systems,
including virtualized ones, provided the kernel is >= 2.6.32 and glibc
is new enough to find and parse the vDSO.
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.
Assert that the request queue is empty when destroying the event loop.
Should catch errors where people call uv_loop_delete() when there are
still in-progress work requests (for example.)
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.
This commit renames the various uv_hrtime() implementations to uv__hrtime().
Libuv uses the high-res timer internally in performance-critical code paths.
Calling the non-public version avoids going through the PLT when libuv is
compiled as a shared object.
The exported uv_hrtime() now has a single definition in src/unix/core.c that
calls uv__hrtime().
A future optimization is to lift the uv__hrtime() declarations into header
files so they can be inlined at the call sites. Then again, linking with -flto
should accomplish the same thing.
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.
Implement a best effort approach to mitigating accept() EMFILE errors.
We have a spare file descriptor stashed away that we close to get below
the EMFILE limit. Next, we accept all pending connections and close them
immediately to signal the clients that we're overloaded - and we are, but
we still keep on trucking.
There is one caveat: it's not reliable in a multi-threaded environment.
The file descriptor limit is per process. Our party trick fails if another
thread opens a file or creates a socket in the time window between us
calling close() and accept().
Fixes#315.
Problem: registering two uv_fs_event_t watchers for the same path, then closing
them, caused a segmentation fault. While active, the watchers didn't work right
either, only one would receive events.
Cause: each watcher has a wd (watch descriptor) that's used as its key in a
binary tree. When you call inotify_watch_add() twice with the same path, the
second call doesn't return a new wd - it returns the existing one. That in turn
resulted in the first handle getting ousted from the binary tree, leaving
dangling pointers.
This commit addresses that by storing the watchers in a queue and storing the
queue in the binary tree instead of storing the watchers directly in the tree.
Fixesjoyent/node#3789.
* replace libev backed timers with a pure libuv implementation
* gut ev_run() and make it take a timeout instead of flags
Incidentally speeds up the loop_count_timed benchmark by about 100%.
The new idle watcher was temporarily disabled in 073a48d due to some semantic
incompatibilities with the previous implementation. This commit resolves those
issues and reactivates the new implementation.
One outstanding bug is that idle watchers can run in a different order
(relative to other handle types) than the old implementation, e.g. (timer, idle)
instead of the expected (idle, timer). This will be fixed in an upcoming commit.
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.
