Some memory was leaked when the uv_udp_t handle was closed when there were
in-flight send requests with a heap allocated buffer list.

That doesn't happen much in practice. In the common case (writing < 5 buffers),
the buffer list is stored inside the uv_udp_send_t structure, not allocated on
the heap.

uv_update_time does not overwrite the high 32 bits of uv_loop_t.time.
It merely increments it by one when the low 32 bits have wrapped. That
means that `time` needs to be initialized to zero before
uv_update_time() is called for the first time.

uv_fs_poll_t has an embedded uv_timer_t handle that got closed at a time when
the memory of the encapsulating handle might already have been deallocated.

Solve that by moving the poller's state into a structure that is allocated on
the heap and can be freed independently.

This is a back-port of commit f97c80fa from the master branch.

Conversion to nanoseconds was overflowing with 32-bit builds.

kstat_data_lookup("clock_Mhz") returns a KSTAT_DATA_INT32 on i386 but a
KSTAT_DATA_INT64 on x86_64.

Make the gcc_version macro conform with what node.js and v8 use. Important
because node.js's common.gypi is going to export it soon.

Ref: joyent/node#3779

This improves uv_getaddrinfo error reporting.

This is closer to the Posix model.

This shouldn't be necessary, but node v0.8 relies on it.

Hopefully this fixes joyent/node#3779.

* It's now more efficient, the file is not opened twice.
* It no longer allows deletion of non-symlink directory reparse points.

Old and new path were accidentally reversed.

This is a back-port of commit cfb06db5 from the master branch.

Fixes joyent/node#3768.

Also clean up the code in various ways.

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.

Fixes joyent/node#3789.

Watches the same file twice. Fails on Linux with a segmentation fault.

Fixes #500.

uv_set_process_title() was susceptible to a format string vulnerability:

  $ node -e 'process.title = Array(42).join("%s")'
  Segmentation fault: 11 (core dumped)

The fix is trivial - call setproctitle("%s", s) instead of setproctitle(s) -
but valgrind complains loudly about reads from and writes to uninitialized
memory in libc. It's not a libuv bug because the test case below triggers the
same warnings:

  #include <sys/types.h>
  #include <unistd.h>

  int main(void)
  {
    setproctitle("%s", "test");
    return 0;
  }

That's why this commit replaces setproctitle() with sysctl(KERN_PROC_ARGS).

This commit reapplies commit a9f6f06f, which got reverted in 69a6afea. The revert
turned out to be unnecessary.

Don't create a new socket descriptor if one has been previously assigned with
uv_pipe_open().

Remember the errno when the socket() syscall fails.

It's making node.js crash when run as root. Backtrace:

  (gdb) bt
  #0  0x00007fff856e3ff9 in __findenv ()
  #1  0x00007fff856e404c in getenv ()
  #2  0x000000010004c850 in loop_init (loop=0x10045a792, flags=8) at ev.c:1707
  #3  0x000000010004cb3b in ev_backend [inlined] () at /Users/tjfontaine/Development/node/deps/uv/src/unix/ev/ev.c:2090
  #4  0x000000010004cb3b in ev_default_loop (flags=1606417108) at ev.c:2092
  #5  0x000000010004e5c6 in uv__loop_init (loop=0x10066e330, default_loop=1) at loop.c:52
  #6  0x0000000100044367 in uv_default_loop () at core.c:196
  #7  0x0000000100004625 in node::Init (argc=1606417456, argv=0x100b0f490) at node.cc:2761
  #8  0x000000010000797d in node::Start (argc=1606417600, argv=0x0) at node.cc:2888
  #9  0x0000000100000ca4 in start ()

This reverts commits:

  b49d6f7c unix: fix uv_set_process_title()
  a9f6f06f unix: fix format string vulnerability in freebsd.c
  a87abc70 unix: avoid buffer overflow in proctitle.c
  dc97d44c unix: move uv_set_process_title() to proctitle.c

Use strncpy() to set the process title, it pads the remainder with nul bytes.
Avoids garbage output on systems where `ps aux` prints the entire proctitle
buffer, not just the characters up to the first '\0'.

Fixes joyent/node#3726.

uv_set_process_title() was susceptible to a format string vulnerability:

  $ node -e 'process.title = Array(42).join("%s")'
  Segmentation fault: 11 (core dumped)

The fix is trivial - call setproctitle("%s", s) instead of setproctitle(s) -
but valgrind complains loudly about reads from and writes to uninitialized
memory in libc. It's not a libuv bug because the test case below triggers the
same warnings:

  #include <stdio.h>
  #include <stdlib.h>
  #include <sys/types.h>
  #include <unistd.h>

  int main(void)
  {
    setproctitle("%s", "test");
    return 0;
  }

That's why this commit replaces setproctitle() with sysctl(KERN_PROC_ARGS).

Get/set process title with uv_strlcpy(), not strncpy(). The latter won't
zero-terminate the result if the destination buffer is too small.

Use hijacking argv array to change process' title. It seems to be working fine
on almost every platform (at least it should not break anything as it's used in
nginx in a similar way).