Questions tagged [c++]
General purpose programming language.
91
questions
0
votes
1
answer
80
views
How to use the base58 in c++
its been a while after i done with my python bitcoin miner
And i realize that python is slower to do mining stuff, so i decided to rebuild it in c++ as you guys know c++ the faster than other ...
1
vote
3
answers
116
views
What protocol do bitcoin nodes use to talk to each other?
I assume it's TCP, but is there some other software used to send and receive data?
So how would I program a very simple C++ program that sends a test message to a node?
- 53
1
vote
1
answer
100
views
Is it possible to use the getboolarg function in interpreter.cpp
I'm looking to use the GetBoolArg() function in the interpreter.cpp file what changes do I have to make for it to work?
I'm still new to development c, I tried several #include but without success.
...
- 107
1
vote
0
answers
36
views
What is the difference between chain and chainman in the NodeContext in the Bitcoin Core?
In the NodeContext structure there are two members named chainman and chain. chainman
is instance of ChainstateManager and chain is instance of interfaces::Chain. What is the differences between these ...
- 1,175
2
votes
1
answer
134
views
What is the nBits field in the CBlockHeader class?
In the source code for the CBlockHeader class, there is a field called nBits.
/** Nodes collect new transactions into a block, hash them into a hash tree,
* and scan through nonce values to make the ...
- 1,175
6
votes
1
answer
2k
views
Why many classes in the Bitcoin Core prefix with a `C` while it is prohibited in the developer notes?
It's part of the developer notes in the documentation of Bitcoin Core:
Class names, function names, and method names are UpperCamelCase
(PascalCase). Do not prefix class names with C. See Internal ...
- 1,175
1
vote
1
answer
152
views
Do I have to worry about endian swapping when calculating ECDSA public key values, Creation & Signing of transactions and verification of signature?
Do I have to worry about endian swapping when calculating ECDSA public key values, Creation & Signing of transactions and verification of signature?
This question is more of a straightforward yes/...
- 75
1
vote
1
answer
65
views
How does AttachChain function works in the Bitcoin Core?
Here in the function AttachChain there is block of code:
// Unless allowed, ensure wallet files are not reused across chains:
if (!gArgs.GetBoolArg("-walletcrosschain", ...
- 1,175
1
vote
1
answer
98
views
Help explaining some C++ code I haven't seen before [closed]
I'm studying for the upcoming pr review club.
if (!m_foreign_outputs.empty()) {
std::string s(m_foreign_outputs.size(), 0);
for (auto i = m_foreign_outputs.size(); i--...
- 331
2
votes
1
answer
232
views
Why Bitcoin Core source code use #include bracket syntax instead of quote syntax
Why Bitcoin Core source code use #include <rpc/wallet.h> bracket syntax instead of #include "rpc/wallet.h" quote syntax. Can intellisense C++ editors understand this option and not ...
- 343
2
votes
2
answers
199
views
How can I configure Vim to work with bitcoin core C++ source code and have Intellisense like functionality?
I use Vim for editing, I installed Conquer Of Completion (COC) plugin and now I can edit C++ projects with Vim taking advantage of syntax highlighting, autocompletion, inline error messages, etc. But ...
- 343
7
votes
2
answers
518
views
Was the addition of OP_NOP codes in Bitcoin 0.3.6 a hard or soft fork?
I'm doing some deeper research into historical consensus changes and it seems like most folks consider the addition of the OP_NOP codes to be a hard fork. Here's the diff for their addition: https://...
- 161
1
vote
2
answers
198
views
What is the actual working implementation code used in double hashing a block header in c++?
I need to successfully generate a hash value based on what i feel so far has been described as a hexadecimal filtered sha256 implementation... or something like that. I've been here , here , here, ...
- 75
1
vote
2
answers
4k
views
Proper way to get sha256 hash in c++ using openssl?
Given the following variables:
unsigned char text [] = "Test String";
unsigned int len = strlen ((const char*) text);
unsigned char hash [SHA256_DIGEST_LENGTH];
Is there any reason to do ...
- 536
1
vote
1
answer
2k
views
How to generate private/public key pairs in c++ using openssl
I have 2 questions:
How can I generate private/public key pairs with c++ and openssl? I don't want them saved to a file. I want the values to be available to my c++ program.
Given a private key, how ...
- 536
4
votes
1
answer
168
views
Why is CAmount a signed integer?
Is there is reason why Bitcoin uses signed instead of unsigned integers for amounts? I can't imagine a scenario where negative amounts could come up. Was it simply something Satoshi implemented for ...
- 83
0
votes
2
answers
105
views
How do i create/implement a midstate function (One that can accurately calculate the midstate of already mined blocks)
I'm creating an AI controlled bitcoin miner but I'm having trouble manually & locally creating a midstate function to be used for optimizing the mining process. Basically I've created independent ...
- 75
3
votes
0
answers
948
views
Compiling bitcoin error : A compiler with support for C++17 language features is required
I am reading the "Mastering bitcoin: Programming the Open Blockchain" book by Andreas Antonopolous. In the chapter about compiling bitcoin, the instructions were to execute first
./autogen....
- 195
3
votes
1
answer
161
views
Why does the chacha20 implemented in the Bitcoin Core use a 64 bit nonce?
The draft of chacha20 uses a 64-bit nonce, but the final version of chacha20 specification uses a 96-bit nonce.
The #9792 PR adds chacha20 to Bitcoin Core. We can see the function ChaCha20::SetIV(...
- 33
2
votes
0
answers
126
views
Version message C++
I learn bitcoin and I am trying to send a version message and get response, respectevily, by using C++. I can not find any examples or articles how to do it in C++. I'm forming request and send it by ...
1
vote
0
answers
26
views
Which wallets support French seed-phrases? [duplicate]
I found an old backup seedphrase but it is has French words in it, and I've been struggling to find wallet to restore it as it seems most wallets support only English. There has to be a wallet that ...
- 11
0
votes
1
answer
58
views
What does net_processing cover conceptually in the Bitcoin Core codebase?
What does net_processing (.h and .cpp) cover conceptually in the Bitcoin Core codebase?
- 14.5k
1
vote
1
answer
146
views
Translate c++ function into python: sha256 hash mismatch [closed]
This is not related to bitcoin but it uses most of the bitcoin codebase. I would like to translate some c++ code into python but struggle really hard to get the hashes right.
This is the function I ...
- 113
1
vote
0
answers
128
views
Use wallet db for locked UTXOs in Bitcoin Core
Related question: Why are UTXO locks stored in memory only?
Sorry this maybe a dumb question for people good with using database in C++ however I am not able to understand what exactly is going wrong ...
user103136
1
vote
1
answer
101
views
What do the classes ChainstateManager, CChainState, CChain and BlockManager do in Bitcoin Core?
What do the classes ChainstateManager, CChainState, CChain and BlockManager do in Bitcoin Core?
Why do CChainState and CChain have a leading 'C', but ChainstateManager and BlockManager don't?
These ...
- 14.5k
1
vote
1
answer
173
views
What is cs_main? Why is it called cs_main?
What is cs_main? Why is it called cs_main?
This question was asked during the May 12th 2021 Bitcoin Core PR review club hosted by John Newbery on a Carl Dong PR to de-globalize ChainstateManager.
(The ...
- 14.5k
1
vote
1
answer
99
views
What does validation cover conceptually in the Bitcoin Core codebase?
What does validation (.h and .cpp) cover conceptually in the Bitcoin Core codebase?
This question was asked by Larry Ruane at the May 12th 2021 Bitcoin Core PR review club on a Carl Dong PR to de-...
- 14.5k
0
votes
1
answer
352
views
how to hash block header in c++
I want to hash a block header in C++ but dont know how.
Im just using a test block at the moment, so that I know what the expected outcome is. https://www.blockchain.com/btc/block/669892
I have a ...
3
votes
1
answer
343
views
How do I hash header block with C++
So im trying to hash a header in C++ and I am having some trouble.
I have tried different libraries (cryptopp, openssl) can't seem to hash the header correctly.
This is the block which I am testing: ...
1
vote
1
answer
61
views
Feasibility of using Ring Signatures with CoinJoin Technique
There is a Ring Signature implementation in C++ by Libbitcoin team. We can find the details in the following GitHub repository. Is it feasible to use Monero like Ring Signatures together with the ...
- 177
6
votes
1
answer
445
views
What version of C++ is used in Bitcoin Core?
I can't find the information on which C++ version is being currently used in bitcoin core project?
Is it decided for future releases somehow? How does the situation looks now?
The only thing I could ...
- 1,664
6
votes
2
answers
910
views
Is it doable to supplant the current Bitcoin Core implementation with another rewritten in a different language?
Can Bitcoin Core be rewritten in another language, let's say Rust, and could such an implementation supplant the current one in C++ without the users of Bitcoin experiencing some sort of reset/lost of ...
- 542
1
vote
0
answers
86
views
How can I add the MySQL C++ connector to Bitcoin Makefile?
I'm trying to add a custom function to my bitcoin client that queries a mysql db. I followed this guide for the basic: https://technology.finra.org/code/compile-run-customize-your-own-bitcoin-client....
- 11
1
vote
2
answers
508
views
How to get block height, if I have only block header?
Imagine I executed ReadBlockFromDisk and now I have valid instance of CBlock.
How do I read height of this block?
CBlock block = ...;
CBlockIndex index(block);
assert (index.nHeight != 0); // fails,...
- 206
0
votes
2
answers
589
views
Problem to link to libsecp256k1 on ARM architecture
Trying to compile with g++ -o addr 69_addr2.cpp $(pkg-config --cflags --libs libbitcoin) is getting me this error:
/usr/bin/ld: /home/pi/libbitcoininstall/lib/libsecp256k1.a(libsecp256k1_la-secp256k1....
- 498
0
votes
1
answer
355
views
where can I get resource such as Blockchain technology in C++
I have found a lot of pdf files about Ethereum smart contract and JavaScript cryptocurrency. I still want to know about resources such as C++ cryptocurrency. Let me know about some good resources.
- 11
1
vote
2
answers
336
views
Was libbitcoin a part of bitcoin core in the past?
I am trying to use c++ code from the book of Antonopoulos for some time now and I seem to lack an include named bitcoin/bitcoin.hpp.
To compile the code the g++ compiler gets a pkg-config input with ...
- 498
2
votes
2
answers
154
views
Is writing unit tests a good way to start contributing to Bitcoin core?
I'm considering writing unit tests to Bitcoin core as a first step to C++ development and Bitcoin contribution. Anyone have any suggestions about the journey I'm about to begin and possible files that ...
2
votes
1
answer
129
views
How to understand wallets?
I'm trying to generate a mnemonic seed, and everything that goes with that. I'm using c++ / libbitcoin, using the following code - https://github.com/libbitcoin/libbitcoin-system/wiki/Examples-from-...
- 21
3
votes
1
answer
236
views
How to update an older C++ code from Antonopoulos' book to work with current libraries?
I am trying to compile a code in C++ from the Book "Mastering Bitcoin" by Antonopoulos (page 69).
I am new to all of this, including C++, python, etc. I see it as a way of doing something ...
- 498
2
votes
2
answers
636
views
Bitcoin value as int64_t or as double
I want to do program that doing some calculations with bitcoin values.
I know bitcoin have 8 digits after decimal point (please correct me).
If I store the value as double I worry that I might lose ...
- 211
1
vote
1
answer
207
views
Bitcoin compilation error: conflicting declaration
I'm trying to compile the Bitcoin source (1) on Ubuntu and I get:
In file included from bench/data.cpp:10:0:
./bench/data/block413567.raw.h:1:40: error: conflicting declaration ‘const unsigned char ...
- 230
0
votes
0
answers
47
views
add mysql dependency configure.ac bitcoin
i am working on bitcoin code, my aim is to move blockchain data to relational db but i am not able to resolve mysql dependency for different platform, platform includes mac and ubuntu. I have tried ...
0
votes
1
answer
122
views
Where is the code which rejects transactions with insuffisent balance?
Simple question but I can’t find the answer again.
Where is the code which rejects transactions when the value of inputs is below the value of outputs (because I think to recall that check works like ...
- 286
1
vote
1
answer
289
views
How happens the serealization the data in the file blkxxxx.dat in the bitcoin
I'm writing a blockchain parser for bitcoin core with C++ and now I want to enrich the data I read with the raw transaction and the previous and next block hashes.
I used this library to convert the ...
- 1,323
1
vote
1
answer
162
views
Why future Bitcoin Core release shouldn't be in python?
Python offers various advantages including simplified rules of coding and ease of readability. It offers OOP, cross platform compatibility and has numerous libraries that have been added over time. It ...
- 7,308
0
votes
1
answer
150
views
How to get amount in RPC
I am developing a bitcoin wallet for education purposes, and i'm working on a getbalance method that given an address i return the balance of the address.
Problem is, when communicating via the RPC ...
- 1
0
votes
1
answer
4k
views
Looking for code generate bitcoin address from passphase in C++
i'm try to write a program which generate bitcoin address from given hash sha256 of passphase as private key or given hex private key. I've found a library for this but it required Boost package in ...
0
votes
1
answer
217
views
find a CTransaction from a prevout in Bitcoin source code
I'm trying to come up with this function: CTransaction getTxFromPrevout(COutPoint prevo);
The idea being... when a new transaction is about to be validated, it will go through all of it's tx.vin[i]....
- 1
0
votes
1
answer
596
views
bitcoin compile (.undefined reference to **')
I'm getting error after make command like,
undefined reference to `BlockAssembler::BlockAssembler(CChainParams const&)'
and in last
Makefile:774: recipe for target 'all-recursive' failed
make:...
- 3