Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Revert r247300 for now. I'll post a new changeset for review.

Expose timespec and timeval macros when __BSD_VISIBLE is defined. This
allows userland application to use the following macros:

timespecclear, timespecisset, timespeccmp, timespecadd,
timespecsub;

timevalclear, timevalisset, timevalcmp.

MFC after: 1 month

- Make truss thread-aware.

Approved by: kib (mentor)
MFC after: 2 weeks

- Fix detaching under some circumstances.

When truss is detaching from very active process it is possible to
hang on waitpid(2) in restore_proc() forever, because
ptrace(PT_SYSCALL) must be called before detaching, to allow the
debugging process to continue execution. Also when truss called with
'-c' argument, it does not print anything after detach, because it
immediately exits from restore_proc().

To fix these two problems make detaching deferred, but then it is
impossible to detach from a process which does not do any system call.
To fix this issue use sigaction(2) instead of signal(3) to disable
SA_RESTART flag for waitpid(2) that makes it non-restartable. Remove
global variable child_pid, because now detaching is handled in context
where child's pid is known.

Reported by: mjg
Tested by: mjg, swills
Approved by: kib (mentor)
MFC after: 2 weeks

- Style(9) cleanup.

Approved by: kib (mentor)

- Use pid_t type instead of just int.

Approved by: kib (mentor)

Fix copyright spelling.

PR: 139825
Submitted by: Ruslan Mahmatkhanov

Add -c option to summarize number of calls, errors, and system time.

Reviewed by: alfred

Make use of ptrace(2) instead of procfs in truss(1), eliminating
yet another need of an available /proc/ mount.

Tested with: make universe
Submitted by: howardsu
Reviewed by: alfred

- Add decoding of kse_release, kevent, sigprocmask, unmount, socket, getrusage,
rename, __getcwd, shutdown, getrlimit, setrlimit, _umtx_lock, _umtx_unlock,
pathconf, truncate, ftruncate, kill

- Decode more arguments of open, mprot, *stat, and fcntl.

- Convert all constant-macro and bitfield decoding to lookup tables; much
cleaner than previous code.

- Print the timestamp of process exit and signal reception when -d or -D are in
use

- Try six times with 1/2 second delay to debug the child

PR: bin/52190 (updated)
Submitted by: Dan Nelson <dnelson@allantgroup.com>
Approved by: alfred

Add a -s flag for the same functionality as strace. Introduce a Name
type which is a String type that has no -s limitations applied to it.
Change most Strings in the code to Names and add a few extra syscalls,
namely munmap, read, rename and symlink. This was enough to facilitate
following file descriptor allocations in the code more easily and
getting a hint at what's being read/written from/to files. More
syscalls should really be added.

While here, fix an off-by-one bug in the buffer truncation code and
add a fflush so that truss's output reflects the syscall that the
program is stuck in.

Sponsored by: Sophos/Activestate
MFC after: 2 weeks

Use timespec not timeval.

Add options to print the argument and environment string parameters to
execve().

This could be done in a more general manner but it still wouldn't
be very pretty.

MFC after: 3 weeks

Add options to print absolute and relative timestamps.

PR: bin/25587 (in part)
MFC after: 3 weeks

Allow tracking fork()ed children.

PR: bin/25587 (in part)
MFC after: 3 weeks

Parameterize globals.

PR: bin/25587 (in part)
MFC after: 3 weeks