This commit simplifies the locking system: CCriticalSection becomes a
simple typedef for boost::interprocess::interprocess_recursive_mutex,
and CCriticalBlock and CTryCriticalBlock are replaced by a templated
CMutexLock, which wraps boost::interprocess::scoped_lock.
By making the lock type a template parameter, some critical sections
can now be changed to non-recursive locks, which support waiting via
condition variables. These are implemented in CWaitableCriticalSection
and WAITABLE_CRITICAL_BLOCK.
CWaitableCriticalSection is a wrapper for a different Boost mutex,
which supports waiting/notification via condition variables. This
should enable us to remove much of the used polling code. Important
is that this mutex is not recursive, so functions that perform the
locking must not call eachother.
Because boost::interprocess::scoped_lock does not support assigning
and copying, I had to revert to the older CRITICAL_BLOCK macros that
use a nested for loop instead of a simple if.
2^31 milliseconds is only about 25 days. Also clamps Sleep() to 10 years,
because it currently sleeps for 0 seconds when the sleep time would cross
2^31 seconds since the epoch. Hopefully boost will be fixed by 2028.
This introduces CNetAddr and CService, respectively wrapping an
(IPv6) IP address and an IP+port combination. This functionality used
to be part of CAddress, which also contains network flags and
connection attempt information. These extra fields are however not
always necessary.
These classes, along with logic for creating connections and doing
name lookups, are moved to netbase.{h,cpp}, which does not depend on
headers.h.
Furthermore, CNetAddr is mostly IPv6-ready, though IPv6
functionality is not yet enabled for the application itself.
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.
SecureString is identical to std::string except with secure_allocator
substituting for std::allocator. This makes casting between them
impossible, so converting between the two at API boundaries requires
calling ::c_str() for now.
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.
util.h doesn't use REF, serialize.h does, creating a dependency of
serialize.h on util.h, but util.h already depends on serialize.h. To
resolve this circular dependency the function 'REF' has now been moved
closer to one of its two points of use.
Signed-off-by: Giel van Schijndel <me@mortis.eu>
In the assert()s take advantage of the fact that string constants
("string") are effectively of type 'const char []', which when used in
an expression yield a non-NULL pointer.
An assertion that should always fail can thus be formulated as:
assert(!"fail);
An assertion where a text message should be added to the expression can
be written as such:
assert("message" && expression);
Signed-off-by: Giel van Schijndel <me@mortis.eu>
Use non-blocking connects, and a select() call to wait a predefined
time (5s by default, but configurable with -timeout) for either
success or failure. This allows much more connections to be tried
per time unit.
Based on a patch by phantomcircuit.
Pieter Wuille