New demonstration CPU miner available

A new CPU miner is now available, making use of the new 'getwork' RPC command.
In the beginning, this is intended largely to demonstrate a 'getwork' miner. It is written in straight C, with minimal dependencies (libcurl, jansson).
It has successfully generated blocks on testnet, mainnet and almost all pools.
Linux/BSD release tarball: http://yyz.us/bitcoin/cpuminer-1.0.2.tar.gz
Windows installer: http://yyz.us/bitcoin/cpuminer-installer-1.0.2.zip
git repository: git://github.com/jgarzik/cpuminer.git
Contributions welcomed! (GPL v2 license)
UPDATE: This has largely been superceded by Con Kolivas's cgminer fork (http://forum.bitcoin.org/index.php?topic=28402.0). See cgminer's official forum thread (http://forum.bitcoin.org/index.php?topic=28402.0) for updates and details.

Quote from: jgarzik on November 25, 2010, 12:45:23 AM (https://bitcointalk.org/index.php?topic=1925.msg24217#msg24217)

In the beginning, this is intended largely to demonstrate a 'getwork' miner. It is written in straight C, with minimal dependencies (libcurl, libcrypto, jansson).

Cool, I like simplicity of your code. I want to try similar implementation in javascript. Partially because of curiosity and partialy because (inspired by hashcash) it can generate few hashes by fighting comments spam :-).
I just made few tests. In four javascript threads I get ~4khash/s, which is EXTREMELY slow. Probably because javascript is interpreted and without any JIT yet. Would be great if javascript supports GPU. Flash will support GPU soon, so we will see .

Quote from: slush on November 25, 2010, 02:14:17 AM (https://bitcointalk.org/index.php?topic=1925.msg24236#msg24236)

Quote from: jgarzik on November 25, 2010, 12:45:23 AM (https://bitcointalk.org/index.php?topic=1925.msg24217#msg24217)

In the beginning, this is intended largely to demonstrate a 'getwork' miner. It is written in straight C, with minimal dependencies (libcurl, libcrypto, jansson).

Cool, I like simplicity of your code. I want to try similar implementation in javascript. Partially because of curiosity and partialy because (inspired by hashcash) it can generate few hashes by fighting comments spam :-).
I just made few tests. In four javascript threads I get ~4khash/s, which is EXTREMELY slow. Probably because javascript is interpreted and without any JIT yet. Would be great if javascript supports GPU. Flash will support GPU soon, so we will see .

Is your JavaScript code available?
I wish the getwork RPC command could be allowed for non-authenticated users from other hosts. It isn't revealing any secret information, is it?

Nice idea on the independent C miner.
On the JS one: Oh no, soon all kinds of websites will be sneakily generating bitcons on the background while you browse them, hogging your CPU even more 

Quote from: sturle on November 25, 2010, 01:28:45 PM (https://bitcointalk.org/index.php?topic=1925.msg24350#msg24350)

Is your JavaScript code available?
I wish the getwork RPC command could be allowed for non-authenticated users from other hosts. It isn't revealing any secret information, is it?

Will be available if I finish that. It is just for curiosity because it will be slow as hell. Also network overhead will be significant.
I expect simple PHP proxy will do good work for hiding credentials to client. something like yourdomain.com/getwork.php which call rpc to localhost and return json encoded data.

Quote from: slush on November 25, 2010, 02:53:20 PM (https://bitcointalk.org/index.php?topic=1925.msg24374#msg24374)

Will be available if I finish that. It is just for curiosity because it will be slow as hell. Also network overhead will be significant.

I believe that IE has cryptographic extensions that you can use from javascript. Maybe that will speed it up?

Quote from: witchspace on November 25, 2010, 02:59:26 PM (https://bitcointalk.org/index.php?topic=1925.msg24376#msg24376)

I believe that IE has cryptographic extensions that you can use from javascript. Maybe that will speed it up?

Do you have any link or reference? I found only 3rd party ActiveX component here http://www.chilkatsoft.com/js-sha512-hash.asp.

Should I use a particular version of jansson? I installed it from git, and get the following compile error:

Code:

util.c: In function ‘json_rpc_call’:
util.c:133:2: warning: passing argument 2 of ‘json_loads’ makes integer from pointer without a cast
/usr/local/include/jansson.h:188:9: note: expected ‘size_t’ but argument is of type ‘struct json_error_t *’
util.c:133:2: error: too few arguments to function ‘json_loads’
/usr/local/include/jansson.h:188:9: note: declared here

Quote from: bugmenot on November 26, 2010, 12:08:00 PM (https://bitcointalk.org/index.php?topic=1925.msg24623#msg24623)

Nice work.
But :

Quote

DBG: found zeroes in hash:
6c1e0d9af9b06eab5aae7fbe058760708c1c7869870142b91b9c0ae300000000
PROOF OF WORK FOUND? submitting...
PROOF OF WORK RESULT: false (booooo)
[...]
DBG: found zeroes in hash:
c155613cbd70edad88bf56b06cbd788329a2a741b27ee78f25abdb2e00000000
PROOF OF WORK FOUND? submitting...
PROOF OF WORK RESULT: false (booooo)

I don't know if this is a bug or not.
The miner has been compiled with cygwin, I don't know if it matters.

Not a bug. The miner finds a hash with "several" zeroes in it, but then relies on bitcoin to do the full 256-bit hash < target value comparison. It's normal that some hashes will be found by the CPU miner, then rejected by bitcoin. We call those almost-solutions 

FWIW, the default bitcoin miner also does this -- it just doesn't print out when it "finds some zeroes", only when a real proof of work is found.
Thus, my CPU miner always shows when it stops working on a solution, and starts working on a new solution. Just giving you a bit more information on the whole process.

Attached is a Windows executable build with mingw32. I'd be interested to know if it works.
run "minerd.exe --help" or "minerd.exe -h" to show command line options.
minerd.exe SHA-1 sum: 722fa3b956de3ed3438ed3294fe191f0d55c1514
minerd.exe MD5 sum: 9f75f8da7a5d02da1d45d46d4a032489

Quote from: teknohog on November 26, 2010, 01:41:39 PM (https://bitcointalk.org/index.php?topic=1925.msg24635#msg24635)

Should I use a particular version of jansson? I installed it from git, and get the following compile error:

Code:

util.c: In function ‘json_rpc_call’:
util.c:133:2: warning: passing argument 2 of ‘json_loads’ makes integer from pointer without a cast
/usr/local/include/jansson.h:188:9: note: expected ‘size_t’ but argument is of type ‘struct json_error_t *’
util.c:133:2: error: too few arguments to function ‘json_loads’
/usr/local/include/jansson.h:188:9: note: declared here

It's been tested with jansson 1.2 and 1.3 release versions.
EDIT: If you lack jansson, current cpuminer.git will build an in-tree version. Thus, you may opt to fix the problem by... removing jansson from your system.