Remembering all time samples makes nTimeOffset slow to respond to
system clock corrections. For instance, I start my node with a system
clock that's 30 minutes slow and run it for a few days. During that
time, I accumulate 10,000 offset samples with a median of 1800
seconds. Now I correct my system clock. Without this change, my node
must collect another 10,000 samples before nTimeOffset is correct
again. With this change, I must only accumulate 100 samples to
correct the offset.
Storing unlimited time samples also allows an attacker with many IP
addresses (ex, a large botnet) to perform a memory exhaustion attack
against Bitcoin nodes. The attacker sends a version message from each
IP to his target, consuming more of the target's memory each time.
Time samples are small, so this attack might be impractical under the
old code, but it's impossible with the new code.
The full list of time samples is rarely useful outside of debugging.
The node's time offset, however is useful for discovering local clock
drift, so it's displayed in all logging modes.
Replaced all occurrences of #if* __WXMSW__ with WIN32,
and all occurrences of __WXMAC_OSX__ with MAC_OSX, and made
sure those are defined appropriately in the makefile and bitcoin-qt.pro.
This replaces the openssl-based base64 encoder and decoder with a more
efficient internal one. Tested against the rfc4648 test vectors.
Decoder is based on JoelKatz' version.
Makefiles now build bitcoind only.
qmake/make in top-level directory is used to build Bitcoin QT
Deleted almost all #ifdef GUI from the code (left one possibly controversial one)
Deleted xpm/ files.
Using the comma as thousands separator causes problems for parts of the world
where comma == decimal point. Germans sending 0,001 bitcoins are unpleasantly
surprised when that results in 1 BTC getting sent.
Gavin Andresen