shadowproject/shadow

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doc/coding.txt

Summary

Maintainability
Test Coverage
Please be consistent with the existing coding style.

Block style:

bool Function(char* psz, int n)
{
    // Comment summarising what this section of code does
    for (int i = 0; i < n; i++)
    {
        // When something fails, return early
        if (!Something())
            return false;
        ...
    }

    // Success return is usually at the end
    return true;
}

- ANSI/Allman block style
- 4 space indenting, no tabs
- No extra spaces inside parenthesis; please don't do ( this )
- No space after function names, one space after if, for and while

Variable names begin with the type in lowercase, like nSomeVariable.
Please don't put the first word of the variable name in lowercase like
someVariable.

Common types:
n       integer number: short, unsigned short, int, unsigned int,
            int64_t, uint64_t, sometimes char if used as a number
d       double, float
f       flag
hash    uint256
p       pointer or array, one p for each level of indirection
psz     pointer to null terminated string
str     string object
v       vector or similar list objects
map     map or multimap
set     set or multiset
bn      CBigNum

-------------------------
Locking/mutex usage notes

The code is multi-threaded, and uses mutexes and the
CRITICAL_BLOCK/TRY_CRITICAL_BLOCK macros to protect data structures.

Deadlocks due to inconsistent lock ordering (thread 1 locks cs_main
and then cs_wallet, while thread 2 locks them in the opposite order:
result, deadlock as each waits for the other to release its lock) are
a problem. Compile with -DDEBUG_LOCKORDER to get lock order
inconsistencies reported in the debug.log file.

Re-architecting the core code so there are better-defined interfaces
between the various components is a goal, with any necessary locking
done by the components (e.g. see the self-contained CKeyStore class
and its cs_KeyStore lock for example).

-------
Threads

StartNode : Starts other threads.

ThreadGetMyExternalIP : Determines outside-the-firewall IP address,
sends addr message to connected peers when it determines it. 

ThreadIRCSeed : Joins IRC bootstrapping channel, watching for new
peers and advertising this node's IP address. 

ThreadSocketHandler : Sends/Receives data from peers on port 8333.

ThreadMessageHandler : Higher-level message handling (sending and
receiving).

ThreadOpenConnections : Initiates new connections to peers.

ThreadTopUpKeyPool : replenishes the keystore's keypool.

ThreadCleanWalletPassphrase : re-locks an encrypted wallet after user
has unlocked it for a period of time. 

SendingDialogStartTransfer : used by pay-via-ip-address code (obsolete)

ThreadDelayedRepaint : repaint the gui 

ThreadFlushWalletDB : Close the wallet.dat file if it hasn't been used
in 500ms.

ThreadRPCServer : Remote procedure call handler, listens on port 8332
for connections and services them.

ThreadBitcoinMiner : Generates bitcoins

ThreadMapPort : Universal plug-and-play startup/shutdown

Shutdown : Does an orderly shutdown of everything

ExitTimeout : Windows-only, sleeps 5 seconds then exits application