A bad interaction between valgrind and clang 6.0.0-1ubuntu2 with -O2
optimizations makes valgrind misleadingly imply C++ code is reading an
uninitialized blockheight value in rest_blockhash_by_height just because that's
what clang optimized code is doing. The C++ code looks like:
int32_t blockheight;
if (!ParseInt32(height_str, &blockheight) || blockheight < 0) {
while the optimized code looks like:
0x00000000000f97ab <+123>: callq 0x4f8860 <ParseInt32(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, int*)>
0x00000000000f97b0 <+128>: mov 0xc(%rsp),%ebx
0x00000000000f97b4 <+132>: test %ebx,%ebx
0x00000000000f97b6 <+134>: js 0xf98aa <rest_blockhash_by_height(util::Ref const&, HTTPRequest*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)+378>
0x00000000000f97bc <+140>: xor $0x1,%al
0x00000000000f97be <+142>: jne 0xf98aa <rest_blockhash_by_height(util::Ref const&, HTTPRequest*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)+378>
During the rest_interface.py test:
self.test_rest_request("/blockhashbyheight/", ret_type=RetType.OBJ, status=400)
when height_str is empty, ParseInt32 returns false and blockheight value is
never assigned. The optimized code reads the uninitialized blockheight value
in 0xc(%rsp) before the checking the ParseInt32 return value in %al, which is
harmless, but triggers the following error from valgrind:
==30660== Thread 13 b-httpworker.2:
==30660== Conditional jump or move depends on uninitialised value(s)
==30660== at 0x2017B6: rest_blockhash_by_height(util::Ref const&, HTTPRequest*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (rest.cpp:614)
==30660== by 0x2041B9: operator() (rest.cpp:670)
==30660== by 0x2041B9: std::_Function_handler<bool (HTTPRequest*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&), StartREST(util::Ref const&)::$_1>::_M_invoke(std::_Any_data const&, HTTPRequest*&&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (std_function.h:301)
==30660== by 0x3EC994: operator() (std_function.h:706)
==30660== by 0x3EC994: HTTPWorkItem::operator()() (httpserver.cpp:55)
==30660== by 0x3ED16D: WorkQueue<HTTPClosure>::Run() (httpserver.cpp:114)
==30660== by 0x3E9168: HTTPWorkQueueRun(WorkQueue<HTTPClosure>*, int) (httpserver.cpp:342)
==30660== by 0x3EDAAA: __invoke_impl<void, void (*)(WorkQueue<HTTPClosure> *, int), WorkQueue<HTTPClosure> *, int> (invoke.h:60)
==30660== by 0x3EDAAA: __invoke<void (*)(WorkQueue<HTTPClosure> *, int), WorkQueue<HTTPClosure> *, int> (invoke.h:95)
==30660== by 0x3EDAAA: _M_invoke<0, 1, 2> (thread:234)
==30660== by 0x3EDAAA: operator() (thread:243)
==30660== by 0x3EDAAA: std:🧵:_State_impl<std:🧵:_Invoker<std::tuple<void (*)(WorkQueue<HTTPClosure>*, int), WorkQueue<HTTPClosure>*, int> > >::_M_run() (thread:186)
==30660== by 0x64256DE: ??? (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.25)
==30660== by 0x54876DA: start_thread (pthread_create.c:463)
==30660== by 0x6DC888E: clone (clone.S:95)
==30660== Uninitialised value was created by a stack allocation
==30660== at 0x20173A: rest_blockhash_by_height(util::Ref const&, HTTPRequest*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (rest.cpp:608)
==30660==
{
<insert_a_suppression_name_here>
Memcheck:Cond
fun:_ZL24rest_blockhash_by_heightRKN4util3RefEP11HTTPRequestRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE
fun:operator()
fun:_ZNSt17_Function_handlerIFbP11HTTPRequestRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEZ9StartRESTRKN4util3RefEE3$_1E9_M_invokeERKSt9_Any_dataOS1_S9_
fun:operator()
fun:_ZN12HTTPWorkItemclEv
fun:_ZN9WorkQueueI11HTTPClosureE3RunEv
fun:_ZL16HTTPWorkQueueRunP9WorkQueueI11HTTPClosureEi
fun:__invoke_impl<void, void (*)(WorkQueue<HTTPClosure> *, int), WorkQueue<HTTPClosure> *, int>
fun:__invoke<void (*)(WorkQueue<HTTPClosure> *, int), WorkQueue<HTTPClosure> *, int>
fun:_M_invoke<0, 1, 2>
fun:operator()
fun:_ZNSt6thread11_State_implINS_8_InvokerISt5tupleIJPFvP9WorkQueueI11HTTPClosureEiES6_iEEEEE6_M_runEv
obj:/usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.25
fun:start_thread
fun:clone
}
This is a known bad interaction between clang and valgrind. The clang optimized
code is correct but valgrind has no way of knowing that accessing the
uninitialized value isn't a problem. Issue has been reported previously:
https://bugs.llvm.org/show_bug.cgi?id=32604#c4https://github.com/Z3Prover/z3/issues/972
This commit just sets blockheight to 0 as a workaround.
Though at the moment ChainActive() simply references `g_chainstate.m_chain`,
doing this change now clears the way for multiple chainstate usage and allows
us to script the diff.
-BEGIN VERIFY SCRIPT-
git grep -l "chainActive" | grep -E '(h|cpp)$' | xargs sed -i '/chainActive =/b; /extern CChain& chainActive/b; s/\(::\)\{0,1\}chainActive/::ChainActive()/g'
-END VERIFY SCRIPT-
04da9f4834 [RPC] Update getrawtransaction interface (Amiti Uttarwar)
Pull request description:
- stop checking unspent UTXOs for a transaction when txindex is not enabled, as per conversation here: https://github.com/bitcoin/bitcoin/issues/3220#issuecomment-377458383
- code contributed by sipa
Tree-SHA512: aa07353bccc14b81b7803992a25d076d6bc06d15ec7c1b85828dc10aea7e0498d9b49f71783e352ab8a14b0bb2010cfb7835de3dfd1bc6f2323f460449348e66
42ff30ec6 [Docs] add short documentation for /rest/blockhashbyheight (Jonas Schnelli)
579d418f7 [QA] add rest tests for /rest/blockhashbyheight/<HEIGHT>.<FORMAT> (Jonas Schnelli)
eb9ef04c4 REST: add "blockhashbyheight" call, fetch blockhash by height (Jonas Schnelli)
Pull request description:
Completes the REST interface for trivial block exploring by adding a call that allows to fetch the blockhash in the main chain by a given height.
Tree-SHA512: 94be9e56718f857279b11cc16dfa8d04f3b5a762e87ae54281b4d87247c71c844895f4944d5a47f09056bf851f4c4761ac4fbdbaaee957265d14de5c1c73e8d2
b9f226b41f rpc: Remove cs_main lock from blockToJSON and blockHeaderToJSON (João Barbosa)
343b98cbcd rpc: Specify chain tip instead of chain in GetDifficulty (João Barbosa)
54dc13b6a2 rpc: Fix SoftForkMajorityDesc and SoftForkDesc signatures (João Barbosa)
Pull request description:
Motivated by https://github.com/bitcoin/bitcoin/pull/11913#discussion_r157798157, this pull makes `blockToJSON` and `blockheaderToJSON` free of `cs_main` locks.
Locking `cs_main` was required to access `chainActive` in order to check if the block was in the chain and to retrieve the next block index.
With the this approach, `CBlockIndex::GetAncestor()` is used in a way to check if the block belongs to the specified chain tip and, at the same time, get the next block index.
Tree-SHA512: a6720ace0182c19033bbed1a404f729d793574db8ab16e0966ffe412145611e32c30aaab02975d225df6d439d7b9ef2070e732b16137a902b0293c8cddfeb85f
This change:
* adds a length check to ParseHashStr, appropriate given its use to populate
a 256-bit number from a hex str.
* allows the caller to handle the failure, which allows for the more
appropriate JSONRPCError on failure in prioritisetransaction rpc
JSON calls do not use the raw data generated for
the .bin and .hex calls. By moving the raw data
creation into the .bin and .hex switch branches,
JSON calls become faster.
Now that the transaction index is updated asynchronously, in order to
preserve the current behavior of public interfaces, the code blocks
until the transaction index is caught up with the current state of the
blockchain.
1f45e21 scripted-diff: Convert 11 enums into scoped enums (C++11) (practicalswift)
Pull request description:
Rationale (from Bjarne Stroustrup's ["C++11 FAQ"](http://www.stroustrup.com/C++11FAQ.html#enum)):
>
> The enum classes ("new enums", "strong enums") address three problems with traditional C++ enumerations:
>
> * conventional enums implicitly convert to int, causing errors when someone does not want an enumeration to act as an integer.
> * conventional enums export their enumerators to the surrounding scope, causing name clashes.
> * the underlying type of an enum cannot be specified, causing confusion, compatibility problems, and makes forward declaration impossible.
>
> The new enums are "enum class" because they combine aspects of traditional enumerations (names values) with aspects of classes (scoped members and absence of conversions).
Tree-SHA512: 9656e1cf4c3cabd4378c7a38d0c2eaf79e4a54d204a3c5762330840e55ee7e141e188a3efb2b4daf0ef3110bbaff80d8b9253abf2a9b015cdc4d60b49ac2b914
A few "a->an" and "an->a".
"Shows, if the supplied default SOCKS5 proxy" -> "Shows if the supplied default SOCKS5 proxy". Change made on 3 occurrences.
"without fully understanding the ramification of a command" -> "without fully understanding the ramifications of a command".
Removed duplicate words such as "the the".
This patch makes several related changes:
* Changes the CCoinsView virtual methods (GetCoins, HaveCoins, ...)
to be COutPoint/Coin-based rather than txid/CCoins-based.
* Changes the chainstate db to a new incompatible format that is also
COutPoint/Coin based.
* Implements reconstruction code for hash_serialized_2.
* Adapts the coins_tests unit tests (thanks to Russell Yanofsky).
A side effect of the new CCoinsView model is that we can no longer
use the (unreliable) test for transaction outputs in the UTXO set
to determine whether we already have a particular transaction.
This makes the following changes:
* In undo data and the chainstate database, the transaction nVersion
field is removed from the data structures, always written as 0, and
ignored when reading.
* The definition of hash_serialized in gettxoutsetinfo is changed to no
longer incude the nVersion field. It is renamed to hash_serialized_2
to avoid confusion. The new definition also includes transaction
height and coinbase information, as this information was missing
before.
This depends on having a CHashVerifier-based undo data checksum
verifier.
Apart from changing the definition of serialized_hash, downgrading
after using this patch is supported, as no release ever used the value
of nVersion field in UTXO entries.
Remove the nType and nVersion as parameters to all serialization methods
and functions. There is only one place where it's read and has an impact
(in CAddress), and even there it does not impact any of the recursively
invoked serializers.
Instead, the few places that need nType or nVersion are changed to read
it directly from the stream object, through GetType() and GetVersion()
methods which are added to all stream classes.
Split out methods to every module, apart from 'help' and 'stop' which
are implemented in rpcserver.cpp itself.
- This makes it easier to add or remove RPC commands - no longer everything that includes
rpcserver.h has to be rebuilt when there's a change there.
- Cleans up `rpc/server.h` by getting rid of the huge cluttered list of function definitions.
- Removes most of the bitcoin-specific code from rpcserver.cpp and .h.
Continues #7307 for the non-wallet.
This patch changes the way the suffix (giving the requested data format) is
parsed for REST requests. Before, the string was split at '.'
characters and it was assumed that the second part was the suffix.
Now, we look for the last dot and use that to determine the suffix.
This allows for strings that contain dots (not used now, though), and
seems, in general, to be clearer and more intuitive.
- *Replace usage of boost::asio with [libevent2](http://libevent.org/)*.
boost::asio is not part of C++11, so unlike other boost there is no
forwards-compatibility reason to stick with it. Together with #4738 (convert
json_spirit to UniValue), this rids Bitcoin Core of the worst offenders with
regard to compile-time slowness.
- *Replace spit-and-duct-tape http server with evhttp*. Front-end http handling
is handled by libevent, a work queue (with configurable depth and parallelism)
is used to handle application requests.
- *Wrap HTTP request in C++ class*; this makes the application code mostly
HTTP-server-neutral
- *Refactor RPC to move all http-specific code to a separate file*.
Theoreticaly this can allow building without HTTP server but with another RPC
backend, e.g. Qt's debug console (currently not implemented) or future RPC
mechanisms people may want to use.
- *HTTP dispatch mechanism*; services (e.g., RPC, REST) register which URL
paths they want to handle.
By using a proven, high-performance asynchronous networking library (also used
by Tor) and HTTP server, problems such as #5674, #5655, #344 should be avoided.
What works? bitcoind, bitcoin-cli, bitcoin-qt. Unit tests and RPC/REST tests
pass. The aim for now is everything but SSL support.
Configuration options:
- `-rpcthreads`: repurposed as "number of work handler threads". Still
defaults to 4.
- `-rpcworkqueue`: maximum depth of work queue. When this is reached, new
requests will return a 500 Internal Error.
- `-rpctimeout`: inactivity time, in seconds, after which to disconnect a
client.
- `-debug=http`: low-level http activity logging
- implement find_value() function for UniValue
- replace all Array/Value/Object types with UniValues, remove JSON Spirit to UniValue wrapper
- remove JSON Spirit sources
03c5687 appropriate response when trying to get a block in pruned mode (Jonas Schnelli)
1b2e555 add autoprune information to RPC "getblockchaininfo" (Jonas Schnelli)
has parts of @mhearn #4351
* allows querying the utxos over REST
* same binary input and outputs as mentioned in Bip64
* input format = output format
* various rpc/rest regtests
- rest block request returns full unfolded tx details
- /rest/block/notxdetails/<HASH> returns block where transactions are only represented by its hash
1. Remove the default format (binary) because `rest/block/<hash>/Hex` would end up delivering binary data.
2. List available formats when chosen format was not found (reduces need for documentation)
3. Change url syntax to dot extension like format chosing (like `rest/tx/<hash>.json`