Add a new library: libulog.

One of the things I really want to do, is to get rid of the limitations
of our current utmp(5) mechanism:

- It only allows 8 byte TTY device names.
- The hostname only allows 16 bytes of storage.

I'm not a big fan of <utmpx.h>, but I think we should at least try to
add parts of it. Unfortunately we cannot implement <utmpx.h>, because we
miss various fields, such as ut_id, ut_pid, etc. The API provided by
libulog shares some similarities with <utmpx.h>, so it shouldn't be too
hard to port these applications eventually. In most simple cases, it
should just be a matter of removing the ulog_ prefix everywhere.

As a bonus, it also implements a function called ulog_login_pseudo(),
which allows unprivileged applications to write log entries, provided
they have a valid file descriptor to a pseudo-terminal master device.

libulog will allow a smoother transition to a new file format by adding
a library interface to deal with utmp/wtmp/lastlog files. I initially
thought about adding the functionality to libutil, but because I'm not
planning on keeping this library around forever, we'd better keep it
separated.

Next items on the todo list:

1. Port applications in the base system (and ports) to libulog, instead
   of letting them use <utmp.h>.
2. Remove <utmp.h>, implement <utmpx.h> and reimplement this library on
   top.
3. Port as many applications as possible back to <utmpx.h>.

1 files changed, 1 insertions, 0 deletions

diff --git a/contrib/groff/tmac/doc-syms b/contrib/groff/tmac/doc-syms
index 25cce80c7446..18fb2048ec03 100644
--- a/contrib/groff/tmac/doc-syms
+++ b/contrib/groff/tmac/doc-syms
@@ -777,6 +777,7 @@
 .ds doc-str-Lb-librt       \*[Px] \*[doc-str-Lb]Real-time Library (librt, \-lrt)
 .ds doc-str-Lb-libtermcap  Termcap Access Library (libtermcap, \-ltermcap)
 .ds doc-str-Lb-libusbhid   USB Human Interface Devices Library (libusbhid, \-lusbhid)
+.ds doc-str-Lb-libulog     User Login Record Library (libulog, \-lulog)
 .ds doc-str-Lb-libutil     System Utilities Library (libutil, \-lutil)
 .ds doc-str-Lb-libx86_64   x86_64 Architecture Library (libx86_64, \-lx86_64)
 .ds doc-str-Lb-libz        Compression Library (libz, \-lz)