Fix deadlocks in setaccount, sendfrom RPC calls

SendMoney*() now requires caller to acquire cs_main.
GetAccountAddress() now requires caller to acquire cs_main, cs_mapWallet.

Ordering is intended to match these two callchains[1]:

1. CRITICAL_BLOCK(cs_main)
    ProcessMessage(pfrom, strCommand, vMsg)
        AddToWalletIfMine()
              AddToWallet(wtx)
                  CRITICAL_BLOCK(cs_mapWallet)

2. CRITICAL_BLOCK(cs_main)
    ProcessMessage(pfrom, strCommand, vMsg)
        AddToWalletIfMine()
              AddToWallet(wtx)
                  CRITICAL_BLOCK(cs_mapWallet)
                      walletdb.WriteName(PubKeyToAddress(vchDefaultKey), "")
                          CRITICAL_BLOCK(cs_mapAddressBook)

Spotted by ArtForz.  Additional deadlock fixes by Gavin.

[1] http://www.bitcoin.org/smf/index.php?topic=4904.msg71897#msg71897

1 files changed, 48 insertions, 34 deletions

diff --git a/rpc.cpp b/rpc.cpp
index 97710ff6b8..a634fff693 100644
--- a/rpc.cpp
+++ b/rpc.cpp
@@ -315,46 +315,45 @@ Value getnewaddress(const Array& params, bool fHelp)
 }
 
 
+// requires cs_main, cs_mapWallet locks
 string GetAccountAddress(string strAccount, bool bForceNew=false)
 {
     string strAddress;
 
-    CRITICAL_BLOCK(cs_mapWallet)
-    {
-        CWalletDB walletdb;
-        walletdb.TxnBegin();
+    CWalletDB walletdb;
+    walletdb.TxnBegin();
 
-        CAccount account;
-        walletdb.ReadAccount(strAccount, account);
+    CAccount account;
+    walletdb.ReadAccount(strAccount, account);
 
-        // Check if the current key has been used
-        if (!account.vchPubKey.empty())
-        {
-            CScript scriptPubKey;
-            scriptPubKey.SetBitcoinAddress(account.vchPubKey);
-            for (map<uint256, CWalletTx>::iterator it = mapWallet.begin();
-                 it != mapWallet.end() && !account.vchPubKey.empty();
-                 ++it)
-            {
-                const CWalletTx& wtx = (*it).second;
-                foreach(const CTxOut& txout, wtx.vout)
-                    if (txout.scriptPubKey == scriptPubKey)
-                        account.vchPubKey.clear();
-            }
-        }
-
-        // Generate a new key
-        if (account.vchPubKey.empty() || bForceNew)
+    // Check if the current key has been used
+    if (!account.vchPubKey.empty())
+    {
+        CScript scriptPubKey;
+        scriptPubKey.SetBitcoinAddress(account.vchPubKey);
+        for (map<uint256, CWalletTx>::iterator it = mapWallet.begin();
+             it != mapWallet.end() && !account.vchPubKey.empty();
+             ++it)
         {
-            account.vchPubKey = GetKeyFromKeyPool();
-            string strAddress = PubKeyToAddress(account.vchPubKey);
-            SetAddressBookName(strAddress, strAccount);
-            walletdb.WriteAccount(strAccount, account);
+            const CWalletTx& wtx = (*it).second;
+            foreach(const CTxOut& txout, wtx.vout)
+                if (txout.scriptPubKey == scriptPubKey)
+                    account.vchPubKey.clear();
         }
+    }
 
-        walletdb.TxnCommit();
-        strAddress = PubKeyToAddress(account.vchPubKey);
+    // Generate a new key
+    if (account.vchPubKey.empty() || bForceNew)
+    {
+        account.vchPubKey = GetKeyFromKeyPool();
+        string strAddress = PubKeyToAddress(account.vchPubKey);
+        SetAddressBookName(strAddress, strAccount);
+        walletdb.WriteAccount(strAccount, account);
     }
+
+    walletdb.TxnCommit();
+    strAddress = PubKeyToAddress(account.vchPubKey);
+
     return strAddress;
 }
 
@@ -368,7 +367,15 @@ Value getaccountaddress(const Array& params, bool fHelp)
     // Parse the account first so we don't generate a key if there's an error
     string strAccount = AccountFromValue(params[0]);
 
-    return GetAccountAddress(strAccount);
+    Value ret;
+
+    CRITICAL_BLOCK(cs_main)
+    CRITICAL_BLOCK(cs_mapWallet)
+    {
+        ret = GetAccountAddress(strAccount);
+    }
+
+    return ret;
 }
 
 
@@ -392,6 +399,8 @@ Value setaccount(const Array& params, bool fHelp)
         strAccount = AccountFromValue(params[1]);
 
     // Detect when changing the account of an address that is the 'unused current key' of another account:
+    CRITICAL_BLOCK(cs_main)
+    CRITICAL_BLOCK(cs_mapWallet)
     CRITICAL_BLOCK(cs_mapAddressBook)
     {
         if (mapAddressBook.count(strAddress))
@@ -475,9 +484,13 @@ Value sendtoaddress(const Array& params, bool fHelp)
     if (params.size() > 3 && params[3].type() != null_type && !params[3].get_str().empty())
         wtx.mapValue["to"]      = params[3].get_str();
 
-    string strError = SendMoneyToBitcoinAddress(strAddress, nAmount, wtx);
-    if (strError != "")
-        throw JSONRPCError(-4, strError);
+    CRITICAL_BLOCK(cs_main)
+    {
+        string strError = SendMoneyToBitcoinAddress(strAddress, nAmount, wtx);
+        if (strError != "")
+            throw JSONRPCError(-4, strError);
+    }
+
     return wtx.GetHash().GetHex();
 }
 
@@ -752,6 +765,7 @@ Value sendfrom(const Array& params, bool fHelp)
     if (params.size() > 5 && params[5].type() != null_type && !params[5].get_str().empty())
         wtx.mapValue["to"]      = params[5].get_str();
 
+    CRITICAL_BLOCK(cs_main)
     CRITICAL_BLOCK(cs_mapWallet)
     {
         // Check funds