Show startup messages immediately

In particular before initialization. So that SF
seems more snappy at startup.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Add (smart) logging facility

By means of "Use Debug Log" UCI option it is possible to toggle
the logging of std::cout to file "out.txt" while preserving
the usual output to stdout. There is zero overhead when logging
is disabled and we achieved this without changing a single line
of exsisting code, in particular we still use std::cout as usual.

The idea and part of the code comes from this article:
http://groups.google.com/group/comp.lang.c++/msg/1d941c0f26ea0d81

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Add also logging of std::cin

Some trial was needed to find the correct recipe but now
we log both stdin and stdout to file "io_log.txt".

Link http://spec.winprog.org/streams/ was very useful
to understand the details of iostreams implementation.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Better on_change() argument name

Using "o" as a parameter with the on_xxx(const UICOption& o)
functions is a bit dangerous because of confusion with "0".

Suggested by Rein Halbersma.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Remove cruft from Logger class

A big code simplification and cruft removing, make
Logger class a singleton and fully self conteined.
Also add direction indicators (">>" and "<<") to
better differentiate input and output lines in the
log file.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Fix Logger under MSVC iostream libraries

We need splitted Tie classes because MSVC stream library
takes a lock on buffer both on reading and on writing and
this causes an hang because, while searching, the I/O
thread is locked on getline() and when main thread is
trying to std::cout() something it blocks on the same
lock waiting for I/O thread getting some input and
releasing the lock.

The solution is to use separated streambuf objects for
cin and cout.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Penalize undefended minors

Even if not under attack. This seems to be good
especially on openings.

After 12112 games at 10"+0.05
Mod vs Orig 2175 - 1997 - 7940 ELO +5 (+- 3.7)

[Patch series from Gary, little edited by me]

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Optimize undefended minor check.
Merge pull request #8 from glinscott/master

Optimize undefended minor check. Little editing by
me, no change even at assembly level.

No regression after 8K games at fast TC on a 64bit CPU.
Penalty for undefended rook as well
Use a local copy of tte->value()

This should avoid some aliasing issues
with TT table access.

After 3913 games at 10"+0.05
Mod vs Orig 662 - 651 - 2600  ELO +0 (+- 6.4)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Merge two loops in ThreadsManager::init()

In analogy with ThreadsManager::exit()

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Remove last platform specific code form thread.cpp

A somewhat tricky function pointer cast allows us
to move the platform specifics to lock.h, the cast
is tricky because return type is not the same of the
casted function in Linux (for Windows return type is
a DWORD that is a long) but this should not be a
problem as long as the size is the same;

From: http://stackoverflow.com/questions/188839/function-pointer-cast-to-different-signature

"OpenSSL was only casting functions pointers to
other function types taking and returning the same
number of values of the same exact sizes, and this
(assuming you're not dealing with floating-point)
happens to be safe across all the platforms and
calling conventions I know of. However, anything
else is potentially unsafe."

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Rename lock.h to platform.h

And move some more platform specific code there.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Fix a MSVC warning

Not correct warning about use of an uninitialized
variable. The warning is not correct becuase we can
never reach the warned code when in SpNode, anyhow
the fix is simple.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Don't ceil cpu_count()

It is already done at calling site where it is
more appropiate.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Revert "Don't sync with C library I/O buffers"

It seems is the cause of strange and rare hangs
reported by some users where Stockfish stops
responding to GUI. It is not clear why but for
the moment revert the patch.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Refactor ThreadsManager::set_size() functionality

Split the data allocation, now done (mostly once)
in read_uci_options(), from the wake up and sleeping
of the slave threads upon entering/exiting the search.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Refactor Thread class

Associate platform OS thread to the Thread class instead of
creating it from ThreadsManager.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Use std::vector<Thread*> to store threads

We store pointers instead of Thread objects because
Thread is not copy-constructible nor copy-assignable
and default ones are not suitable. So we cannot store
directly in a std::vector.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>