Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Minor changes from Berkeley DB 1.86 and further improvements from OpenBSD.
This does not include the new hash routines since they will cause problems
when reading old hash files.

Since mpool(3) has been changed, provide a compatibility shim for older
binaries.

Obtained from: OpenBSD

db/btree/bt_open.c: check return value of snprintf() and return value
if the result is truncated.

db/hash/hash_page.c: use the same way to create temporary file as
bt_open.c; check snprintf() return value.

Obtained from: OpenBSD

When allocating memory, zero out them if we don't intend to overwrite them
all; before freeing memory, zero out them before we release it as free
heap. This will eliminate some potential information leak issue.

While there, remove the PURIFY option. There is a slight difference between
the new behavior and the old -DPURIFY behavior, with the latter initializes
memory with 0xff's. The difference between old and new approach does not
generate observable difference.

Obtained from: OpenBSD (partly).

Save errno before calling _close(), which may clear it.

Obtained from: OpenBSD

Style changes (including additional casts to shut up warnings). This
commit does not affect MD5 of object file.

Diff reduction against OpenBSD: ANSI'fy prototypes.

(This is part of a larger changeset which is intended to reduce diff only,
thus some prototypes were left intact since they will be changed in the
future).

Verified with: md5(1)

Per Regents of the University of Calfornia letter, remove advertising
clause.

# If I've done so improperly on a file, please let me know.

Fix the style of the SCM ID's.
I believe have made all of libc .c's as consistent as possible.

Remove __P() usage.

Remove _THREAD_SAFE and make libc thread-safe by default by
adding (weak definitions to) stubs for some of the pthread
functions. If the threads library is linked in, the real
pthread functions will pulled in.

Use the following convention for system calls wrapped by the
threads library:
__sys_foo - actual system call
_foo - weak definition to __sys_foo
foo - weak definition to __sys_foo

Change all libc uses of system calls wrapped by the threads
library from foo to _foo. In order to define the prototypes
for _foo(), we introduce namespace.h and un-namespace.h
(suggested by bde). All files that need to reference these
system calls, should include namespace.h before any standard
includes, then include un-namespace.h after the standard
includes and before any local includes. <db.h> is an exception
and shouldn't be included in between namespace.h and
un-namespace.h namespace.h will define foo to _foo, and
un-namespace.h will undefine foo.

Try to eliminate some of the recursive calls to MT-safe
functions in libc/stdio in preparation for adding a mutex
to FILE. We have recursive mutexes, but would like to avoid
using them if possible.

Remove uneeded includes of <errno.h> from a few files.

Add $FreeBSD$ to a few files in order to pass commitprep.

Approved by: -arch

More secure temporary filename. This needs to be revisited to use
mkstemp().

Simplify sytem call renaming. Instead of _foo() <-- _libc_foo <-- foo(),
just use _foo() <-- foo(). In the case of a libpthread that doesn't do
call conversion (such as linuxthreads and our upcoming libpthread), this
is adequate. In the case of libc_r, we still need three names, which are
now _thread_sys_foo() <-- _foo() <-- foo().

Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(),
nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo().

Remove all internal libc usage of: creat(), pause(), sleep(), system(),
tcdrain(), wait(), and waitpid().

Make thread cancellation fully POSIX-compliant.

Suggested by: deischen

Add three-tier symbol naming in support of POSIX thread cancellation
points. For library functions, the pattern is __sleep() <--
_libc_sleep() <-- sleep(). The arrows represent weak aliases. For
system calls, the pattern is _read() <-- _libc_read() <-- read().

Don't trust TMPDIR if we're setuid root. This is used only for the
backing file for an anonymous (memory based) btree, and I don't think
that any setuid programs actually use it, but it is better to be safe
than sorry. This has been in my tree for a long time, maybe a year or
more...

Inspired by: Similar changes in OpenBSD, if memory serves (like nearly
a year ago)

General -Wall warning cleanup, part I.
Submitted-By: Kent Vander Velden <graphix@iastate.edu>

Fix conflicts and merge into mainline

Remove trailing whitespace.

This commit was generated by cvs2svn to compensate for changes in r1573,
which included commits to RCS files with non-trunk default branches.

BSD 4.4 Lite Lib Sources