This improves API consistency with uv_read and uv_write and may
improve efficiency for some uses. Vectored IO is emulated when the
requisite system calls are unavailable.
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
Changed the order of the member assignments since the thread
may start before the parameters are assigned. This especially
happens when the osx scheduler is very busy.
When building using gyp and BUILDTYPE=Release using clang 3.4 received
this warning:
../src/unix/linux-core.c:640:34: warning: variable 'n' is uninitialized
for (len = sizeof("cpu0"); n /= 10; len++);
^
Initializing n = 0 silences this build warning.
Thus allow passing the same file descriptor as the source of multiple
stdios.
Committed with the help and code parts from:
* Sam Roberts <sam@strongloop.com>
fix#1074
CPU entries in /proc/stat are not guaranteed to be monotonically
increasing, asserting on this assumption can break in cases such
as the UltraSparc II machine shown in #1080.
Signed-off-by: Luca Bruno <lucab@debian.org>
uv__stream_osx_interrupt_select was only defined on OS X, but is used
elsewhere on all platforms. The intention was to implement it as a
no-op on other platforms, but the entire definition was inside
"#ifdef __APPLE__", so this didn't actually work.
Fix: move it above the #ifdef.
Relying on `readable`/`writable` when polling will lead to the select
thread spinning in the loop and calling `uv_async_send()`, because
stream may never become not `readable`/`writable`.
We should rely on `uv__io_active()` instead and interruprt select thread
every time it changes.
If multiple handles arrive to the IPC pipe at the same time (happens on
some platforms), libuv will queue them internally, and call `read2_cb`
multiple times with a null-buffer and proper `handle_type`.
In our build infrastructure, I've seen a lot of segfaults recently that
were all only happening on OSX. Upon inspecting the coredumps, it
appearded that all segfaults happened at the same instruction, and upon
translating the assembly back to the source, I found that an array could
be indexed with a -1 index before the index was checked to be not -1.
As concrete evidence, here is the situation that I found caused the
segfault. The instruction in question along with the relevant register
values was:
mov (%r8,%r15,8),%r12
r8 = 0x7fb0ba800000
r15 = 0xffffffffffffffff
r8 + r15 * 8 == 0x7fb0ba7ffff8
It appears that the base of loop->watchers was page aligned, and by
going back one word I guess that the page wasn't mapped, causing our
segfaults.
In our build infrastructure, I've seen a lot of segfaults recently that
were all only happening on OSX. Upon inspecting the coredumps, it
appearded that all segfaults happened at the same instruction, and upon
translating the assembly back to the source, I found that an array could
be indexed with a -1 index before the index was checked to be not -1.
As concrete evidence, here is the situation that I found caused the
segfault. The instruction in question along with the relevant register
values was:
mov (%r8,%r15,8),%r12
r8 = 0x7fb0ba800000
r15 = 0xffffffffffffffff
r8 + r15 * 8 == 0x7fb0ba7ffff8
It appears that the base of loop->watchers was page aligned, and by
going back one word I guess that the page wasn't mapped, causing our
segfaults.
Useful to know when the the event loop is empty, this can't be done with
uv_run() without possibly blocking, or running some events (which might
empty the event loop as a side-effect).
Some scandir implementations allocate the dirent struct even if the
directory is empty, so if `scandir` returns 0 there may still be memory
that needs to get deallocated. I have altered uv__fs_readdir to go to
the "deallocation exit area" when 0 files are found in the directory
and continue to return early on a return value of -1.
I went to add a test for this functionality, but it appears that one
already exists (reading an empty directory), so I imagine that the
valgrind builds must only be happening on linux instead of OSX as well?
I have confirmed manually that a program without this fix will
infinitely leak memory, and with this fix the memory usage stays
constant.
`uv_try_write(stream, buf, size)` acts like `uv_write()`,
but without queueing actual write until UV_POLLOUT (or IOCP completion).
This is useful for doing writes using on-stack `uv_write_t` requests.
fix#1025
First of all, a bit of explanation of what happens there:
1. FSEvents emits absolute paths to changed files or directories
2. We cut off the first part of such paths, which is equal to handle's
real path ('/dir/subdir/subsubdir`, without trailing slash)
3. Then, if we are running in non-recursive mode, we discard paths that
have slashes ('/') as a non-first character in them
Commit 3d2c820 back-ports a patch from the master branch that disables
the use of SO_REUSEPORT on Linux for reasons mentioned in the commit
log.
Unfortunately, the back-port was incomplete; another setsockopt() call
site in src/unix/udp.c was overlooked. This commit rectifies that.
Hat tip to Luca Bruno for helping troubleshoot the issue.
Fix a bug that was introduced in commit 3ee4d3f ("unix, windows:
return error codes directly") and add a regression test for good
measure.
Hat tip to Fedor for pointing out the issue.
Fixes#1007.
Print the error message rather than just the errno. The fact that the
errno is 24 is only informative to people that have their operating
system's error codes memorized.
Set the close-on-exec flag on file descriptors that we've received with
recvmsg() so we don't leak them when calling fork() afterwards.
On Linux, we use the MSG_CMSG_CLOEXEC flag when supported (2.6.23 and
up.)
On older Linux versions and other platforms, we walk the received file
descriptors and set the close-on-exec flag for each fd manually. That
won't entirely avoid race conditions when other threads call fork() or
clone() but at least we're less likely to leak file descriptors now.
When fd is closed and new one (with the same number) is opened inside
kqueue/epoll/port loop's callback - stale events might invoke callbacks
on wrong watchers.
Check if watcher was changed after invocation and invalidate all events
with the same fd.
fix#826
Otherwise `FSEventStreamCreate()` will coalesce events, even if they're
happening in the interval, bigger than supplied `latency`. In other
words, if this flag is not set events will happen in separate callback
only if there was a delay bigger than `latency` between two consecutive
events.
Work around an epoll quirk where it sometimes reports just the EPOLLERR
or EPOLLHUP event. In order to force the event loop to move forward,
we merge in the read/write events that the watcher is interested in;
uv__read() and uv__write() will then deal with the error or hangup in
the usual fashion.
Fixes#982.
This is a back-port of commit 24bfef2 from the master branch.
Work around an epoll quirk where it sometimes reports just the EPOLLERR
or EPOLLHUP event. In order to force the event loop to move forward,
we merge in the read/write events that the watcher is interested in;
uv__read() and uv__write() will then deal with the error or hangup in
the usual fashion.
Fixes#982.
