Update ethash Godep

2015-06-16 12:06:06 +02:00
parent 8f372c867d
commit a9d6846f92
16 changed files with 76 additions and 13958 deletions
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/CMakeLists.txt
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/CMakeLists.txt
@@ -9,13 +9,6 @@ if (WIN32 AND WANT_CRYPTOPP)
 endif()

 add_subdirectory(src/libethash)
-# bin2h.cmake doesn't work
-if (NOT OpenCL_FOUND)
-	find_package(OpenCL)
-endif()

-if (OpenCL_FOUND)
-	add_subdirectory(src/libethash-cl)
-endif()
 add_subdirectory(src/benchmark EXCLUDE_FROM_ALL)
 add_subdirectory(test/c)
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/ethash.go
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/ethash.go
@@ -8,6 +8,7 @@ int ethashGoCallback_cgo(unsigned);
 import "C"

 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -119,6 +120,12 @@ func (l *Light) Verify(block pow.Block) bool {
 	if !ret.success {
 		return false
 	}
+
+	// avoid mixdigest malleability as it's not included in a block's "hashNononce"
+	if !bytes.Equal(block.MixDigest().Bytes(), C.GoBytes(unsafe.Pointer(&ret.mix_hash), C.int(32))) {
+		return false
+	}
+
 	// Make sure cache is live until after the C call.
 	// This is important because a GC might happen and execute
 	// the finalizer before the call completes.
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/CMakeLists.txt
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/CMakeLists.txt
@@ -1,47 +0,0 @@
-cmake_minimum_required(VERSION 2.8)
-
-set(LIBRARY ethash-cl)
-set(CMAKE_BUILD_TYPE Release)
-
-include(bin2h.cmake)
-bin2h(SOURCE_FILE ethash_cl_miner_kernel.cl
-      VARIABLE_NAME ethash_cl_miner_kernel
-      HEADER_FILE ${CMAKE_CURRENT_BINARY_DIR}/ethash_cl_miner_kernel.h)
-
-if (NOT MSVC)
-	# Initialize CXXFLAGS for c++11
-    set(CMAKE_CXX_FLAGS                "-Wall -std=c++11")
-    set(CMAKE_CXX_FLAGS_DEBUG          "-O0 -g")
-    set(CMAKE_CXX_FLAGS_MINSIZEREL     "-Os -DNDEBUG")
-    set(CMAKE_CXX_FLAGS_RELEASE        "-O3 -DNDEBUG")
-    set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2 -g")
-
-    # Compiler-specific C++11 activation.
-    if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
-        execute_process(
-            COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION)
-        if (NOT (GCC_VERSION VERSION_GREATER 4.7 OR GCC_VERSION VERSION_EQUAL 4.7))
-            message(FATAL_ERROR "${PROJECT_NAME} requires g++ 4.7 or greater.")
-        endif ()
-    elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
-    else ()
-        message(FATAL_ERROR "Your C++ compiler does not support C++11.")
-    endif ()
-endif()
-
-set(OpenCL_FOUND TRUE)
-set(OpenCL_INCLUDE_DIRS /usr/include/CL)
-set(OpenCL_LIBRARIES -lOpenCL)
-
-if (NOT OpenCL_FOUND)
-	find_package(OpenCL)
-endif()
-
-if (OpenCL_FOUND)
-	set(CMAKE_CXX_FLAGS "-std=c++11 -Wall -Wno-unknown-pragmas -Wextra -Werror -pedantic -fPIC ${CMAKE_CXX_FLAGS}")
-	include_directories(${OpenCL_INCLUDE_DIRS} ${CMAKE_CURRENT_BINARY_DIR})
-	include_directories(..)
-	add_library(${LIBRARY} ethash_cl_miner.cpp ethash_cl_miner.h cl.hpp)
-	TARGET_LINK_LIBRARIES(${LIBRARY} ${OpenCL_LIBRARIES} ethash)
-endif()
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/bin2h.cmake
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/bin2h.cmake
@@ -1,86 +0,0 @@
-# https://gist.github.com/sivachandran/3a0de157dccef822a230
-include(CMakeParseArguments)
-
-# Function to wrap a given string into multiple lines at the given column position.
-# Parameters:
-#   VARIABLE    - The name of the CMake variable holding the string.
-#   AT_COLUMN   - The column position at which string will be wrapped.
-function(WRAP_STRING)
-    set(oneValueArgs VARIABLE AT_COLUMN)
-    cmake_parse_arguments(WRAP_STRING "${options}" "${oneValueArgs}" "" ${ARGN})
-
-    string(LENGTH ${${WRAP_STRING_VARIABLE}} stringLength)
-    math(EXPR offset "0")
-
-    while(stringLength GREATER 0)
-
-        if(stringLength GREATER ${WRAP_STRING_AT_COLUMN})
-            math(EXPR length "${WRAP_STRING_AT_COLUMN}")
-        else()
-            math(EXPR length "${stringLength}")
-        endif()
-
-        string(SUBSTRING ${${WRAP_STRING_VARIABLE}} ${offset} ${length} line)
-        set(lines "${lines}\n${line}")
-
-        math(EXPR stringLength "${stringLength} - ${length}")
-        math(EXPR offset "${offset} + ${length}")
-    endwhile()
-
-    set(${WRAP_STRING_VARIABLE} "${lines}" PARENT_SCOPE)
-endfunction()
-
-# Function to embed contents of a file as byte array in C/C++ header file(.h). The header file
-# will contain a byte array and integer variable holding the size of the array.
-# Parameters
-#   SOURCE_FILE     - The path of source file whose contents will be embedded in the header file.
-#   VARIABLE_NAME   - The name of the variable for the byte array. The string "_SIZE" will be append
-#                     to this name and will be used a variable name for size variable.
-#   HEADER_FILE     - The path of header file.
-#   APPEND          - If specified appends to the header file instead of overwriting it
-#   NULL_TERMINATE  - If specified a null byte(zero) will be append to the byte array. This will be
-#                     useful if the source file is a text file and we want to use the file contents
-#                     as string. But the size variable holds size of the byte array without this
-#                     null byte.
-# Usage:
-#   bin2h(SOURCE_FILE "Logo.png" HEADER_FILE "Logo.h" VARIABLE_NAME "LOGO_PNG")
-function(BIN2H)
-    set(options APPEND NULL_TERMINATE)
-    set(oneValueArgs SOURCE_FILE VARIABLE_NAME HEADER_FILE)
-    cmake_parse_arguments(BIN2H "${options}" "${oneValueArgs}" "" ${ARGN})
-
-    # reads source file contents as hex string
-    file(READ ${BIN2H_SOURCE_FILE} hexString HEX)
-    string(LENGTH ${hexString} hexStringLength)
-
-    # appends null byte if asked
-    if(BIN2H_NULL_TERMINATE)
-        set(hexString "${hexString}00")
-    endif()
-
-    # wraps the hex string into multiple lines at column 32(i.e. 16 bytes per line)
-    wrap_string(VARIABLE hexString AT_COLUMN 32)
-    math(EXPR arraySize "${hexStringLength} / 2")
-
-    # adds '0x' prefix and comma suffix before and after every byte respectively
-    string(REGEX REPLACE "([0-9a-f][0-9a-f])" "0x\\1, " arrayValues ${hexString})
-    # removes trailing comma
-    string(REGEX REPLACE ", $" "" arrayValues ${arrayValues})
-
-    # converts the variable name into proper C identifier
-    IF (${CMAKE_VERSION} GREATER 2.8.10) # fix for legacy cmake
-        string(MAKE_C_IDENTIFIER "${BIN2H_VARIABLE_NAME}" BIN2H_VARIABLE_NAME)
-    ENDIF()
-    string(TOUPPER "${BIN2H_VARIABLE_NAME}" BIN2H_VARIABLE_NAME)
-
-    # declares byte array and the length variables
-    set(arrayDefinition "const unsigned char ${BIN2H_VARIABLE_NAME}[] = { ${arrayValues} };")
-    set(arraySizeDefinition "const size_t ${BIN2H_VARIABLE_NAME}_SIZE = ${arraySize};")
-
-    set(declarations "${arrayDefinition}\n\n${arraySizeDefinition}\n\n")
-    if(BIN2H_APPEND)
-        file(APPEND ${BIN2H_HEADER_FILE} "${declarations}")
-    else()
-        file(WRITE ${BIN2H_HEADER_FILE} "${declarations}")
-    endif()
-endfunction()
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/cl.hpp
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/cl.hpp
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/ethash_cl_miner.cpp
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/ethash_cl_miner.cpp
@@ -1,384 +0,0 @@
-/*
-  This file is part of c-ethash.
-
-  c-ethash is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  c-ethash is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
-*/
-/** @file ethash_cl_miner.cpp
-* @author Tim Hughes <tim@twistedfury.com>
-* @date 2015
-*/
-
-
-#define _CRT_SECURE_NO_WARNINGS
-
-#include <cstdio>
-#include <cstdlib>
-#include <iostream>
-#include <assert.h>
-#include <queue>
-#include <vector>
-#include <libethash/util.h>
-#include <libethash/ethash.h>
-#include <libethash/internal.h>
-#include "ethash_cl_miner.h"
-#include "ethash_cl_miner_kernel.h"
-
-#define ETHASH_BYTES 32
-
-// workaround lame platforms
-#if !CL_VERSION_1_2
-#define CL_MAP_WRITE_INVALIDATE_REGION CL_MAP_WRITE
-#define CL_MEM_HOST_READ_ONLY 0
-#endif
-
-#undef min
-#undef max
-
-using namespace std;
-
-static void add_definition(std::string& source, char const* id, unsigned value)
-{
-	char buf[256];
-	sprintf(buf, "#define %s %uu\n", id, value);
-	source.insert(source.begin(), buf, buf + strlen(buf));
-}
-
-ethash_cl_miner::search_hook::~search_hook() {}
-
-ethash_cl_miner::ethash_cl_miner()
-:	m_opencl_1_1()
-{
-}
-
-std::string ethash_cl_miner::platform_info(unsigned _platformId, unsigned _deviceId)
-{
-	std::vector<cl::Platform> platforms;
-	cl::Platform::get(&platforms);
-	if (platforms.empty())
-	{
-		cout << "No OpenCL platforms found." << endl;
-		return std::string();
-	}
-
-	// get GPU device of the selected platform
-	std::vector<cl::Device> devices;
-	unsigned platform_num = std::min<unsigned>(_platformId, platforms.size() - 1);
-	platforms[platform_num].getDevices(CL_DEVICE_TYPE_ALL, &devices);
-	if (devices.empty())
-	{
-		cout << "No OpenCL devices found." << endl;
-		return std::string();
-	}
-
-	// use selected default device
-	unsigned device_num = std::min<unsigned>(_deviceId, devices.size() - 1);
-	cl::Device& device = devices[device_num];
-	std::string device_version = device.getInfo<CL_DEVICE_VERSION>();
-
-	return "{ \"platform\": \"" + platforms[platform_num].getInfo<CL_PLATFORM_NAME>() + "\", \"device\": \"" + device.getInfo<CL_DEVICE_NAME>() + "\", \"version\": \"" + device_version + "\" }";
-}
-
-unsigned ethash_cl_miner::get_num_devices(unsigned _platformId)
-{
-	std::vector<cl::Platform> platforms;
-	cl::Platform::get(&platforms);
-	if (platforms.empty())
-	{
-		cout << "No OpenCL platforms found." << endl;
-		return 0;
-	}
-
-	std::vector<cl::Device> devices;
-	unsigned platform_num = std::min<unsigned>(_platformId, platforms.size() - 1);
-	platforms[platform_num].getDevices(CL_DEVICE_TYPE_ALL, &devices);
-	if (devices.empty())
-	{
-		cout << "No OpenCL devices found." << endl;
-		return 0;
-	}
-	return devices.size();
-}
-
-void ethash_cl_miner::finish()
-{
-	if (m_queue())
-		m_queue.finish();
-}
-
-bool ethash_cl_miner::init(uint64_t block_number, std::function<void(void*)> _fillDAG, unsigned workgroup_size, unsigned _platformId, unsigned _deviceId)
-{
-	// store params
-	m_fullSize = ethash_get_datasize(block_number);
-
-	// get all platforms
-	std::vector<cl::Platform> platforms;
-	cl::Platform::get(&platforms);
-	if (platforms.empty())
-	{
-		cout << "No OpenCL platforms found." << endl;
-		return false;
-	}
-
-	// use selected platform
-	_platformId = std::min<unsigned>(_platformId, platforms.size() - 1);
-
-	cout << "Using platform: " << platforms[_platformId].getInfo<CL_PLATFORM_NAME>().c_str() << endl;
-
-	// get GPU device of the default platform
-	std::vector<cl::Device> devices;
-	platforms[_platformId].getDevices(CL_DEVICE_TYPE_ALL, &devices);
-	if (devices.empty())
-	{
-		cout << "No OpenCL devices found." << endl;
-		return false;
-	}
-
-	// use selected device
-	cl::Device& device = devices[std::min<unsigned>(_deviceId, devices.size() - 1)];
-	std::string device_version = device.getInfo<CL_DEVICE_VERSION>();
-	cout << "Using device: " << device.getInfo<CL_DEVICE_NAME>().c_str() << "(" << device_version.c_str() << ")" << endl;
-
-	if (strncmp("OpenCL 1.0", device_version.c_str(), 10) == 0)
-	{
-		cout << "OpenCL 1.0 is not supported." << endl;
-		return false;
-	}
-	if (strncmp("OpenCL 1.1", device_version.c_str(), 10) == 0)
-		m_opencl_1_1 = true;
-
-	// create context
-	m_context = cl::Context(std::vector<cl::Device>(&device, &device + 1));
-	m_queue = cl::CommandQueue(m_context, device);
-
-	// use requested workgroup size, but we require multiple of 8
-	m_workgroup_size = ((workgroup_size + 7) / 8) * 8;
-
-	// patch source code
-	std::string code(ETHASH_CL_MINER_KERNEL, ETHASH_CL_MINER_KERNEL + ETHASH_CL_MINER_KERNEL_SIZE);
-	add_definition(code, "GROUP_SIZE", m_workgroup_size);
-	add_definition(code, "DAG_SIZE", (unsigned)(m_fullSize / ETHASH_MIX_BYTES));
-	add_definition(code, "ACCESSES", ETHASH_ACCESSES);
-	add_definition(code, "MAX_OUTPUTS", c_max_search_results);
-	//debugf("%s", code.c_str());
-
-	// create miner OpenCL program
-	cl::Program::Sources sources;
-	sources.push_back({code.c_str(), code.size()});
-
-	cl::Program program(m_context, sources);
-	try
-	{
-		program.build({device});
-	}
-	catch (cl::Error err)
-	{
-		cout << program.getBuildInfo<CL_PROGRAM_BUILD_LOG>(device).c_str();
-		return false;
-	}
-	m_hash_kernel = cl::Kernel(program, "ethash_hash");
-	m_search_kernel = cl::Kernel(program, "ethash_search");
-
-	// create buffer for dag
-	m_dag = cl::Buffer(m_context, CL_MEM_READ_ONLY, m_fullSize);
-
-	// create buffer for header
-	m_header = cl::Buffer(m_context, CL_MEM_READ_ONLY, 32);
-
-	// compute dag on CPU
-	{
-		// if this throws then it's because we probably need to subdivide the dag uploads for compatibility
-		void* dag_ptr = m_queue.enqueueMapBuffer(m_dag, true, m_opencl_1_1 ? CL_MAP_WRITE : CL_MAP_WRITE_INVALIDATE_REGION, 0, m_fullSize);
-		// memcpying 1GB: horrible... really. horrible. but necessary since we can't mmap *and* gpumap.
-		_fillDAG(dag_ptr);
-		m_queue.enqueueUnmapMemObject(m_dag, dag_ptr);
-	}
-
-	// create mining buffers
-	for (unsigned i = 0; i != c_num_buffers; ++i)
-	{
-		m_hash_buf[i] = cl::Buffer(m_context, CL_MEM_WRITE_ONLY | (!m_opencl_1_1 ? CL_MEM_HOST_READ_ONLY : 0), 32*c_hash_batch_size);
-		m_search_buf[i] = cl::Buffer(m_context, CL_MEM_WRITE_ONLY, (c_max_search_results + 1) * sizeof(uint32_t));
-	}
-	return true;
-}
-
-void ethash_cl_miner::hash(uint8_t* ret, uint8_t const* header, uint64_t nonce, unsigned count)
-{
-	struct pending_batch
-	{
-		unsigned base;
-		unsigned count;
-		unsigned buf;
-	};
-	std::queue<pending_batch> pending;
-
-	// update header constant buffer
-	m_queue.enqueueWriteBuffer(m_header, true, 0, 32, header);
-
-	/*
-	__kernel void ethash_combined_hash(
-		__global hash32_t* g_hashes,
-		__constant hash32_t const* g_header,
-		__global hash128_t const* g_dag,
-		ulong start_nonce,
-		uint isolate
-		)
-	*/
-	m_hash_kernel.setArg(1, m_header);
-	m_hash_kernel.setArg(2, m_dag);
-	m_hash_kernel.setArg(3, nonce);
-	m_hash_kernel.setArg(4, ~0u); // have to pass this to stop the compile unrolling the loop
-
-	unsigned buf = 0;
-	for (unsigned i = 0; i < count || !pending.empty(); )
-	{
-		// how many this batch
-		if (i < count)
-		{
-			unsigned const this_count = std::min<unsigned>(count - i, c_hash_batch_size);
-			unsigned const batch_count = std::max<unsigned>(this_count, m_workgroup_size);
-
-			// supply output hash buffer to kernel
-			m_hash_kernel.setArg(0, m_hash_buf[buf]);
-
-			// execute it!
-			m_queue.enqueueNDRangeKernel(
-				m_hash_kernel,
-				cl::NullRange,
-				cl::NDRange(batch_count),
-				cl::NDRange(m_workgroup_size)
-				);
-			m_queue.flush();
-
-			pending.push({i, this_count, buf});
-			i += this_count;
-			buf = (buf + 1) % c_num_buffers;
-		}
-
-		// read results
-		if (i == count || pending.size() == c_num_buffers)
-		{
-			pending_batch const& batch = pending.front();
-
-			// could use pinned host pointer instead, but this path isn't that important.
-			uint8_t* hashes = (uint8_t*)m_queue.enqueueMapBuffer(m_hash_buf[batch.buf], true, CL_MAP_READ, 0, batch.count * ETHASH_BYTES);
-			memcpy(ret + batch.base*ETHASH_BYTES, hashes, batch.count*ETHASH_BYTES);
-			m_queue.enqueueUnmapMemObject(m_hash_buf[batch.buf], hashes);
-
-			pending.pop();
-		}
-	}
-}
-
-
-void ethash_cl_miner::search(uint8_t const* header, uint64_t target, search_hook& hook)
-{
-	struct pending_batch
-	{
-		uint64_t start_nonce;
-		unsigned buf;
-	};
-	std::queue<pending_batch> pending;
-
-	static uint32_t const c_zero = 0;
-
-	// update header constant buffer
-	m_queue.enqueueWriteBuffer(m_header, false, 0, 32, header);
-	for (unsigned i = 0; i != c_num_buffers; ++i)
-	{
-		m_queue.enqueueWriteBuffer(m_search_buf[i], false, 0, 4, &c_zero);
-	}
-
-#if CL_VERSION_1_2 && 0
-	cl::Event pre_return_event;
-	if (!m_opencl_1_1)
-	{
-		m_queue.enqueueBarrierWithWaitList(NULL, &pre_return_event);
-	}
-	else
-#endif
-	{
-		m_queue.finish();
-	}
-
-	/*
-	__kernel void ethash_combined_search(
-		__global hash32_t* g_hashes,			// 0
-		__constant hash32_t const* g_header,	// 1
-		__global hash128_t const* g_dag,		// 2
-		ulong start_nonce,						// 3
-		ulong target,							// 4
-		uint isolate							// 5
-	)
-	*/
-	m_search_kernel.setArg(1, m_header);
-	m_search_kernel.setArg(2, m_dag);
-
-	// pass these to stop the compiler unrolling the loops
-	m_search_kernel.setArg(4, target);
-	m_search_kernel.setArg(5, ~0u);
-
-
-	unsigned buf = 0;
-	for (uint64_t start_nonce = 0; ; start_nonce += c_search_batch_size)
-	{
-		// supply output buffer to kernel
-		m_search_kernel.setArg(0, m_search_buf[buf]);
-		m_search_kernel.setArg(3, start_nonce);
-
-		// execute it!
-		m_queue.enqueueNDRangeKernel(m_search_kernel, cl::NullRange, c_search_batch_size, m_workgroup_size);
-
-		pending.push({start_nonce, buf});
-		buf = (buf + 1) % c_num_buffers;
-
-		// read results
-		if (pending.size() == c_num_buffers)
-		{
-			pending_batch const& batch = pending.front();
-
-			// could use pinned host pointer instead
-			uint32_t* results = (uint32_t*)m_queue.enqueueMapBuffer(m_search_buf[batch.buf], true, CL_MAP_READ, 0, (1+c_max_search_results) * sizeof(uint32_t));
-			unsigned num_found = std::min<unsigned>(results[0], c_max_search_results);
-
-			uint64_t nonces[c_max_search_results];
-			for (unsigned i = 0; i != num_found; ++i)
-			{
-				nonces[i] = batch.start_nonce + results[i+1];
-			}
-
-			m_queue.enqueueUnmapMemObject(m_search_buf[batch.buf], results);
-
-			bool exit = num_found && hook.found(nonces, num_found);
-			exit |= hook.searched(batch.start_nonce, c_search_batch_size); // always report searched before exit
-			if (exit)
-				break;
-
-			// reset search buffer if we're still going
-			if (num_found)
-				m_queue.enqueueWriteBuffer(m_search_buf[batch.buf], true, 0, 4, &c_zero);
-
-			pending.pop();
-		}
-	}
-
-	// not safe to return until this is ready
-#if CL_VERSION_1_2 && 0
-	if (!m_opencl_1_1)
-	{
-		pre_return_event.wait();
-	}
-#endif
-}
-
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/ethash_cl_miner.h
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/ethash_cl_miner.h
@@ -1,57 +0,0 @@
-#pragma once
-
-#define __CL_ENABLE_EXCEPTIONS
-#define CL_USE_DEPRECATED_OPENCL_2_0_APIS
-
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunused-parameter"
-#include "cl.hpp"
-#pragma clang diagnostic pop
-#else
-#include "cl.hpp"
-#endif
-
-#include <time.h>
-#include <functional>
-#include <libethash/ethash.h>
-
-class ethash_cl_miner
-{
-public:
-	struct search_hook
-	{
-		virtual ~search_hook(); // always a virtual destructor for a class with virtuals.
-
-		// reports progress, return true to abort
-		virtual bool found(uint64_t const* nonces, uint32_t count) = 0;
-		virtual bool searched(uint64_t start_nonce, uint32_t count) = 0;
-	};
-
-public:
-	ethash_cl_miner();
-
-	bool init(uint64_t block_number, std::function<void(void*)> _fillDAG, unsigned workgroup_size = 64, unsigned _platformId = 0, unsigned _deviceId = 0);
-	static std::string platform_info(unsigned _platformId = 0, unsigned _deviceId = 0);
-	static unsigned get_num_devices(unsigned _platformId = 0);
-
-
-	void finish();
-	void hash(uint8_t* ret, uint8_t const* header, uint64_t nonce, unsigned count);
-	void search(uint8_t const* header, uint64_t target, search_hook& hook);
-
-private:
-	enum { c_max_search_results = 63, c_num_buffers = 2, c_hash_batch_size = 1024, c_search_batch_size = 1024*256 };
-
-	uint64_t m_fullSize;
-	cl::Context m_context;
-	cl::CommandQueue m_queue;
-	cl::Kernel m_hash_kernel;
-	cl::Kernel m_search_kernel;
-	cl::Buffer m_dag;
-	cl::Buffer m_header;
-	cl::Buffer m_hash_buf[c_num_buffers];
-	cl::Buffer m_search_buf[c_num_buffers];
-	unsigned m_workgroup_size;
-	bool m_opencl_1_1;
-};
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/ethash_cl_miner_kernel.cl
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash-cl/ethash_cl_miner_kernel.cl
@@ -1,460 +0,0 @@
-// author Tim Hughes <tim@twistedfury.com>
-// Tested on Radeon HD 7850
-// Hashrate: 15940347 hashes/s
-// Bandwidth: 124533 MB/s
-// search kernel should fit in <= 84 VGPRS (3 wavefronts)
-
-#define THREADS_PER_HASH (128 / 16)
-#define HASHES_PER_LOOP (GROUP_SIZE / THREADS_PER_HASH)
-
-#define FNV_PRIME	0x01000193
-
-__constant uint2 const Keccak_f1600_RC[24] = {
-	(uint2)(0x00000001, 0x00000000),
-	(uint2)(0x00008082, 0x00000000),
-	(uint2)(0x0000808a, 0x80000000),
-	(uint2)(0x80008000, 0x80000000),
-	(uint2)(0x0000808b, 0x00000000),
-	(uint2)(0x80000001, 0x00000000),
-	(uint2)(0x80008081, 0x80000000),
-	(uint2)(0x00008009, 0x80000000),
-	(uint2)(0x0000008a, 0x00000000),
-	(uint2)(0x00000088, 0x00000000),
-	(uint2)(0x80008009, 0x00000000),
-	(uint2)(0x8000000a, 0x00000000),
-	(uint2)(0x8000808b, 0x00000000),
-	(uint2)(0x0000008b, 0x80000000),
-	(uint2)(0x00008089, 0x80000000),
-	(uint2)(0x00008003, 0x80000000),
-	(uint2)(0x00008002, 0x80000000),
-	(uint2)(0x00000080, 0x80000000),
-	(uint2)(0x0000800a, 0x00000000),
-	(uint2)(0x8000000a, 0x80000000),
-	(uint2)(0x80008081, 0x80000000),
-	(uint2)(0x00008080, 0x80000000),
-	(uint2)(0x80000001, 0x00000000),
-	(uint2)(0x80008008, 0x80000000),
-};
-
-void keccak_f1600_round(uint2* a, uint r, uint out_size)
-{
-   #if !__ENDIAN_LITTLE__
-	for (uint i = 0; i != 25; ++i)
-		a[i] = a[i].yx;
-   #endif
-
-	uint2 b[25];
-	uint2 t;
-
-	// Theta
-	b[0] = a[0] ^ a[5] ^ a[10] ^ a[15] ^ a[20];
-	b[1] = a[1] ^ a[6] ^ a[11] ^ a[16] ^ a[21];
-	b[2] = a[2] ^ a[7] ^ a[12] ^ a[17] ^ a[22];
-	b[3] = a[3] ^ a[8] ^ a[13] ^ a[18] ^ a[23];
-	b[4] = a[4] ^ a[9] ^ a[14] ^ a[19] ^ a[24];
-	t = b[4] ^ (uint2)(b[1].x << 1 | b[1].y >> 31, b[1].y << 1 | b[1].x >> 31);
-	a[0] ^= t;
-	a[5] ^= t;
-	a[10] ^= t;
-	a[15] ^= t;
-	a[20] ^= t;
-	t = b[0] ^ (uint2)(b[2].x << 1 | b[2].y >> 31, b[2].y << 1 | b[2].x >> 31);
-	a[1] ^= t;
-	a[6] ^= t;
-	a[11] ^= t;
-	a[16] ^= t;
-	a[21] ^= t;
-	t = b[1] ^ (uint2)(b[3].x << 1 | b[3].y >> 31, b[3].y << 1 | b[3].x >> 31);
-	a[2] ^= t;
-	a[7] ^= t;
-	a[12] ^= t;
-	a[17] ^= t;
-	a[22] ^= t;
-	t = b[2] ^ (uint2)(b[4].x << 1 | b[4].y >> 31, b[4].y << 1 | b[4].x >> 31);
-	a[3] ^= t;
-	a[8] ^= t;
-	a[13] ^= t;
-	a[18] ^= t;
-	a[23] ^= t;
-	t = b[3] ^ (uint2)(b[0].x << 1 | b[0].y >> 31, b[0].y << 1 | b[0].x >> 31);
-	a[4] ^= t;
-	a[9] ^= t;
-	a[14] ^= t;
-	a[19] ^= t;
-	a[24] ^= t;
-
-	// Rho Pi
-	b[0] = a[0];
-	b[10] = (uint2)(a[1].x << 1 | a[1].y >> 31, a[1].y << 1 | a[1].x >> 31);
-	b[7] = (uint2)(a[10].x << 3 | a[10].y >> 29, a[10].y << 3 | a[10].x >> 29);
-	b[11] = (uint2)(a[7].x << 6 | a[7].y >> 26, a[7].y << 6 | a[7].x >> 26);
-	b[17] = (uint2)(a[11].x << 10 | a[11].y >> 22, a[11].y << 10 | a[11].x >> 22);
-	b[18] = (uint2)(a[17].x << 15 | a[17].y >> 17, a[17].y << 15 | a[17].x >> 17);
-	b[3] = (uint2)(a[18].x << 21 | a[18].y >> 11, a[18].y << 21 | a[18].x >> 11);
-	b[5] = (uint2)(a[3].x << 28 | a[3].y >> 4, a[3].y << 28 | a[3].x >> 4);
-	b[16] = (uint2)(a[5].y << 4 | a[5].x >> 28, a[5].x << 4 | a[5].y >> 28);
-	b[8] = (uint2)(a[16].y << 13 | a[16].x >> 19, a[16].x << 13 | a[16].y >> 19);
-	b[21] = (uint2)(a[8].y << 23 | a[8].x >> 9, a[8].x << 23 | a[8].y >> 9);
-	b[24] = (uint2)(a[21].x << 2 | a[21].y >> 30, a[21].y << 2 | a[21].x >> 30);
-	b[4] = (uint2)(a[24].x << 14 | a[24].y >> 18, a[24].y << 14 | a[24].x >> 18);
-	b[15] = (uint2)(a[4].x << 27 | a[4].y >> 5, a[4].y << 27 | a[4].x >> 5);
-	b[23] = (uint2)(a[15].y << 9 | a[15].x >> 23, a[15].x << 9 | a[15].y >> 23);
-	b[19] = (uint2)(a[23].y << 24 | a[23].x >> 8, a[23].x << 24 | a[23].y >> 8);
-	b[13] = (uint2)(a[19].x << 8 | a[19].y >> 24, a[19].y << 8 | a[19].x >> 24);
-	b[12] = (uint2)(a[13].x << 25 | a[13].y >> 7, a[13].y << 25 | a[13].x >> 7);
-	b[2] = (uint2)(a[12].y << 11 | a[12].x >> 21, a[12].x << 11 | a[12].y >> 21);
-	b[20] = (uint2)(a[2].y << 30 | a[2].x >> 2, a[2].x << 30 | a[2].y >> 2);
-	b[14] = (uint2)(a[20].x << 18 | a[20].y >> 14, a[20].y << 18 | a[20].x >> 14);
-	b[22] = (uint2)(a[14].y << 7 | a[14].x >> 25, a[14].x << 7 | a[14].y >> 25);
-	b[9] = (uint2)(a[22].y << 29 | a[22].x >> 3, a[22].x << 29 | a[22].y >> 3);
-	b[6] = (uint2)(a[9].x << 20 | a[9].y >> 12, a[9].y << 20 | a[9].x >> 12);
-	b[1] = (uint2)(a[6].y << 12 | a[6].x >> 20, a[6].x << 12 | a[6].y >> 20);
-
-	// Chi
-	a[0] = bitselect(b[0] ^ b[2], b[0], b[1]);
-	a[1] = bitselect(b[1] ^ b[3], b[1], b[2]);
-	a[2] = bitselect(b[2] ^ b[4], b[2], b[3]);
-	a[3] = bitselect(b[3] ^ b[0], b[3], b[4]);
-	if (out_size >= 4)
-	{
-		a[4] = bitselect(b[4] ^ b[1], b[4], b[0]);
-		a[5] = bitselect(b[5] ^ b[7], b[5], b[6]);
-		a[6] = bitselect(b[6] ^ b[8], b[6], b[7]);
-		a[7] = bitselect(b[7] ^ b[9], b[7], b[8]);
-		a[8] = bitselect(b[8] ^ b[5], b[8], b[9]);
-		if (out_size >= 8)
-		{
-			a[9] = bitselect(b[9] ^ b[6], b[9], b[5]);
-			a[10] = bitselect(b[10] ^ b[12], b[10], b[11]);
-			a[11] = bitselect(b[11] ^ b[13], b[11], b[12]);
-			a[12] = bitselect(b[12] ^ b[14], b[12], b[13]);
-			a[13] = bitselect(b[13] ^ b[10], b[13], b[14]);
-			a[14] = bitselect(b[14] ^ b[11], b[14], b[10]);
-			a[15] = bitselect(b[15] ^ b[17], b[15], b[16]);
-			a[16] = bitselect(b[16] ^ b[18], b[16], b[17]);
-			a[17] = bitselect(b[17] ^ b[19], b[17], b[18]);
-			a[18] = bitselect(b[18] ^ b[15], b[18], b[19]);
-			a[19] = bitselect(b[19] ^ b[16], b[19], b[15]);
-			a[20] = bitselect(b[20] ^ b[22], b[20], b[21]);
-			a[21] = bitselect(b[21] ^ b[23], b[21], b[22]);
-			a[22] = bitselect(b[22] ^ b[24], b[22], b[23]);
-			a[23] = bitselect(b[23] ^ b[20], b[23], b[24]);
-			a[24] = bitselect(b[24] ^ b[21], b[24], b[20]);
-		}
-	}
-
-	// Iota
-	a[0] ^= Keccak_f1600_RC[r];
-
-   #if !__ENDIAN_LITTLE__
-	for (uint i = 0; i != 25; ++i)
-		a[i] = a[i].yx;
-   #endif
-}
-
-void keccak_f1600_no_absorb(ulong* a, uint in_size, uint out_size, uint isolate)
-{
-	for (uint i = in_size; i != 25; ++i)
-	{
-		a[i] = 0;
-	}
-#if __ENDIAN_LITTLE__
-	a[in_size] ^= 0x0000000000000001;
-	a[24-out_size*2] ^= 0x8000000000000000;
-#else
-	a[in_size] ^= 0x0100000000000000;
-	a[24-out_size*2] ^= 0x0000000000000080;
-#endif
-
-	// Originally I unrolled the first and last rounds to interface
-	// better with surrounding code, however I haven't done this
-	// without causing the AMD compiler to blow up the VGPR usage.
-	uint r = 0;
-	do
-	{
-		// This dynamic branch stops the AMD compiler unrolling the loop
-		// and additionally saves about 33% of the VGPRs, enough to gain another
-		// wavefront. Ideally we'd get 4 in flight, but 3 is the best I can
-		// massage out of the compiler. It doesn't really seem to matter how
-		// much we try and help the compiler save VGPRs because it seems to throw
-		// that information away, hence the implementation of keccak here
-		// doesn't bother.
-		if (isolate) 
-		{
-			keccak_f1600_round((uint2*)a, r++, 25);
-		}
-	}
-	while (r < 23);
-	
-	// final round optimised for digest size
-	keccak_f1600_round((uint2*)a, r++, out_size);
-}
-
-#define copy(dst, src, count) for (uint i = 0; i != count; ++i) { (dst)[i] = (src)[i]; }
-
-#define countof(x) (sizeof(x) / sizeof(x[0]))
-
-uint fnv(uint x, uint y)
-{
-	return x * FNV_PRIME ^ y;
-}
-
-uint4 fnv4(uint4 x, uint4 y)
-{
-	return x * FNV_PRIME ^ y;
-}
-
-uint fnv_reduce(uint4 v)
-{
-	return fnv(fnv(fnv(v.x, v.y), v.z), v.w);
-}
-
-typedef union
-{
-	ulong ulongs[32 / sizeof(ulong)];
-	uint uints[32 / sizeof(uint)];
-} hash32_t;
-
-typedef union
-{
-	ulong ulongs[64 / sizeof(ulong)];
-	uint4 uint4s[64 / sizeof(uint4)];
-} hash64_t;
-
-typedef union
-{
-	uint uints[128 / sizeof(uint)];
-	uint4 uint4s[128 / sizeof(uint4)];
-} hash128_t;
-
-hash64_t init_hash(__constant hash32_t const* header, ulong nonce, uint isolate)
-{
-	hash64_t init;
-	uint const init_size = countof(init.ulongs);
-	uint const hash_size = countof(header->ulongs);
-	
-	// sha3_512(header .. nonce)
-	ulong state[25];
-	copy(state, header->ulongs, hash_size);
-	state[hash_size] = nonce;
-	keccak_f1600_no_absorb(state, hash_size + 1, init_size, isolate);
-
-	copy(init.ulongs, state, init_size);
-	return init;
-}
-
-uint inner_loop(uint4 init, uint thread_id, __local uint* share, __global hash128_t const* g_dag, uint isolate)
-{
-	uint4 mix = init;
-
-	// share init0
-	if (thread_id == 0)
-		*share = mix.x;
-	barrier(CLK_LOCAL_MEM_FENCE);
-	uint init0 = *share;
-
-	uint a = 0;
-	do
-	{
-		bool update_share = thread_id == (a/4) % THREADS_PER_HASH;
-
-		#pragma unroll
-		for (uint i = 0; i != 4; ++i)
-		{
-			if (update_share)
-			{
-				uint m[4] = { mix.x, mix.y, mix.z, mix.w };
-				*share = fnv(init0 ^ (a+i), m[i]) % DAG_SIZE;
-			}
-			barrier(CLK_LOCAL_MEM_FENCE);
-
-			mix = fnv4(mix, g_dag[*share].uint4s[thread_id]);
-		}
-	}
-	while ((a += 4) != (ACCESSES & isolate));
-
-	return fnv_reduce(mix);
-}
-
-hash32_t final_hash(hash64_t const* init, hash32_t const* mix, uint isolate)
-{
-	ulong state[25];
-
-	hash32_t hash;
-	uint const hash_size = countof(hash.ulongs);
-	uint const init_size = countof(init->ulongs);
-	uint const mix_size = countof(mix->ulongs);
-
-	// keccak_256(keccak_512(header..nonce) .. mix);
-	copy(state, init->ulongs, init_size);
-	copy(state + init_size, mix->ulongs, mix_size);
-	keccak_f1600_no_absorb(state, init_size+mix_size, hash_size, isolate);
-
-	// copy out
-	copy(hash.ulongs, state, hash_size);
-	return hash;
-}
-
-hash32_t compute_hash_simple(
-	__constant hash32_t const* g_header,
-	__global hash128_t const* g_dag,
-	ulong nonce,
-	uint isolate
-	)
-{
-	hash64_t init = init_hash(g_header, nonce, isolate);
-
-	hash128_t mix;
-	for (uint i = 0; i != countof(mix.uint4s); ++i)
-	{
-		mix.uint4s[i] = init.uint4s[i % countof(init.uint4s)];
-	}
-	
-	uint mix_val = mix.uints[0];
-	uint init0 = mix.uints[0];
-	uint a = 0;
-	do
-	{
-		uint pi = fnv(init0 ^ a, mix_val) % DAG_SIZE;
-		uint n = (a+1) % countof(mix.uints);
-
-		#pragma unroll
-		for (uint i = 0; i != countof(mix.uints); ++i)
-		{
-			mix.uints[i] = fnv(mix.uints[i], g_dag[pi].uints[i]);
-			mix_val = i == n ? mix.uints[i] : mix_val;
-		}
-	}
-	while (++a != (ACCESSES & isolate));
-
-	// reduce to output
-	hash32_t fnv_mix;
-	for (uint i = 0; i != countof(fnv_mix.uints); ++i)
-	{
-		fnv_mix.uints[i] = fnv_reduce(mix.uint4s[i]);
-	}
-	
-	return final_hash(&init, &fnv_mix, isolate);
-}
-
-typedef union
-{
-	struct
-	{
-		hash64_t init;
-		uint pad; // avoid lds bank conflicts
-	};
-	hash32_t mix;
-} compute_hash_share;
-
-hash32_t compute_hash(
-	__local compute_hash_share* share,
-	__constant hash32_t const* g_header,
-	__global hash128_t const* g_dag,
-	ulong nonce,
-	uint isolate
-	)
-{
-	uint const gid = get_global_id(0);
-
-	// Compute one init hash per work item.
-	hash64_t init = init_hash(g_header, nonce, isolate);
-
-	// Threads work together in this phase in groups of 8.
-	uint const thread_id = gid % THREADS_PER_HASH;
-	uint const hash_id = (gid % GROUP_SIZE) / THREADS_PER_HASH;
-
-	hash32_t mix;
-	uint i = 0;
-	do
-	{
-		// share init with other threads
-		if (i == thread_id)
-			share[hash_id].init = init;
-		barrier(CLK_LOCAL_MEM_FENCE);
-
-		uint4 thread_init = share[hash_id].init.uint4s[thread_id % (64 / sizeof(uint4))];
-		barrier(CLK_LOCAL_MEM_FENCE);
-
-		uint thread_mix = inner_loop(thread_init, thread_id, share[hash_id].mix.uints, g_dag, isolate);
-
-		share[hash_id].mix.uints[thread_id] = thread_mix;
-		barrier(CLK_LOCAL_MEM_FENCE);
-
-		if (i == thread_id)
-			mix = share[hash_id].mix;
-		barrier(CLK_LOCAL_MEM_FENCE);
-	}
-	while (++i != (THREADS_PER_HASH & isolate));
-
-	return final_hash(&init, &mix, isolate);
-}
-
-__attribute__((reqd_work_group_size(GROUP_SIZE, 1, 1)))
-__kernel void ethash_hash_simple(
-	__global hash32_t* g_hashes,
-	__constant hash32_t const* g_header,
-	__global hash128_t const* g_dag,
-	ulong start_nonce,
-	uint isolate
-	)
-{
-	uint const gid = get_global_id(0);
-	g_hashes[gid] = compute_hash_simple(g_header, g_dag, start_nonce + gid, isolate);
-}
-
-__attribute__((reqd_work_group_size(GROUP_SIZE, 1, 1)))
-__kernel void ethash_search_simple(
-	__global volatile uint* restrict g_output,
-	__constant hash32_t const* g_header,
-	__global hash128_t const* g_dag,
-	ulong start_nonce,
-	ulong target,
-	uint isolate
-	)
-{
-	uint const gid = get_global_id(0);
-	hash32_t hash = compute_hash_simple(g_header, g_dag, start_nonce + gid, isolate);
-	if (as_ulong(as_uchar8(hash.ulongs[0]).s76543210) < target)
-	{
-		uint slot = min(MAX_OUTPUTS, atomic_inc(&g_output[0]) + 1);
-		g_output[slot] = gid;
-	}
-}
-
-__attribute__((reqd_work_group_size(GROUP_SIZE, 1, 1)))
-__kernel void ethash_hash(
-	__global hash32_t* g_hashes,
-	__constant hash32_t const* g_header,
-	__global hash128_t const* g_dag,
-	ulong start_nonce,
-	uint isolate
-	)
-{
-	__local compute_hash_share share[HASHES_PER_LOOP];
-
-	uint const gid = get_global_id(0);
-	g_hashes[gid] = compute_hash(share, g_header, g_dag, start_nonce + gid, isolate);
-}
-
-__attribute__((reqd_work_group_size(GROUP_SIZE, 1, 1)))
-__kernel void ethash_search(
-	__global volatile uint* restrict g_output,
-	__constant hash32_t const* g_header,
-	__global hash128_t const* g_dag,
-	ulong start_nonce,
-	ulong target,
-	uint isolate
-	)
-{
-	__local compute_hash_share share[HASHES_PER_LOOP];
-
-	uint const gid = get_global_id(0);
-	hash32_t hash = compute_hash(share, g_header, g_dag, start_nonce + gid, isolate);
-
-	if (as_ulong(as_uchar8(hash.ulongs[0]).s76543210) < target)
-	{
-		uint slot = min(MAX_OUTPUTS, atomic_inc(&g_output[0]) + 1);
-		g_output[slot] = gid;
-	}
-}
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/endian.h
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/endian.h
@@ -32,6 +32,9 @@
 #include <libkern/OSByteOrder.h>
 #define ethash_swap_u32(input_) OSSwapInt32(input_)
 #define ethash_swap_u64(input_) OSSwapInt64(input_)
+#elif defined(__FreeBSD__) || defined(__DragonFly__) || defined(__NetBSD__)
+#define ethash_swap_u32(input_) bswap32(input_)
+#define ethash_swap_u64(input_) bswap64(input_)
 #else // posix
 #include <byteswap.h>
 #define ethash_swap_u32(input_) __bswap_32(input_)
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/internal.c
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/internal.c
@@ -364,6 +364,7 @@ static bool ethash_mmap(struct ethash_full* ret, FILE* f)
 {
 	int fd;
 	char* mmapped_data;
+	errno = 0;
 	ret->file = f;
 	if ((fd = ethash_fileno(ret->file)) == -1) {
 		return false;
@@ -400,38 +401,48 @@ ethash_full_t ethash_full_new_internal(
 	ret->file_size = (size_t)full_size;
 	switch (ethash_io_prepare(dirname, seed_hash, &f, (size_t)full_size, false)) {
 	case ETHASH_IO_FAIL:
+		// ethash_io_prepare will do all ETHASH_CRITICAL() logging in fail case
 		goto fail_free_full;
 	case ETHASH_IO_MEMO_MATCH:
 		if (!ethash_mmap(ret, f)) {
+			ETHASH_CRITICAL("mmap failure()");
 			goto fail_close_file;
 		}
 		return ret;
 	case ETHASH_IO_MEMO_SIZE_MISMATCH:
 		// if a DAG of same filename but unexpected size is found, silently force new file creation
 		if (ethash_io_prepare(dirname, seed_hash, &f, (size_t)full_size, true) != ETHASH_IO_MEMO_MISMATCH) {
+			ETHASH_CRITICAL("Could not recreate DAG file after finding existing DAG with unexpected size.");
 			goto fail_free_full;
 		}
 		// fallthrough to the mismatch case here, DO NOT go through match
 	case ETHASH_IO_MEMO_MISMATCH:
 		if (!ethash_mmap(ret, f)) {
+			ETHASH_CRITICAL("mmap failure()");
 			goto fail_close_file;
 		}
 		break;
 	}

 	if (!ethash_compute_full_data(ret->data, full_size, light, callback)) {
+		ETHASH_CRITICAL("Failure at computing DAG data.");
 		goto fail_free_full_data;
 	}

 	// after the DAG has been filled then we finalize it by writting the magic number at the beginning
 	if (fseek(f, 0, SEEK_SET) != 0) {
+		ETHASH_CRITICAL("Could not seek to DAG file start to write magic number.");
 		goto fail_free_full_data;
 	}
 	uint64_t const magic_num = ETHASH_DAG_MAGIC_NUM;
 	if (fwrite(&magic_num, ETHASH_DAG_MAGIC_NUM_SIZE, 1, f) != 1) {
+		ETHASH_CRITICAL("Could not write magic number to DAG's beginning.");
+		goto fail_free_full_data;
+	}
+	if (fflush(f) != 0) {// make sure the magic number IS there
+		ETHASH_CRITICAL("Could not flush memory mapped data to DAG file. Insufficient space?");
 		goto fail_free_full_data;
 	}
-	fflush(f); // make sure the magic number IS there
 	return ret;

 fail_free_full_data:
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io.c
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io.c
@@ -21,6 +21,7 @@
 #include "io.h"
 #include <string.h>
 #include <stdio.h>
+#include <errno.h>

 enum ethash_io_rc ethash_io_prepare(
 	char const* dirname,
@@ -32,15 +33,19 @@ enum ethash_io_rc ethash_io_prepare(
 {
 	char mutable_name[DAG_MUTABLE_NAME_MAX_SIZE];
 	enum ethash_io_rc ret = ETHASH_IO_FAIL;
+	// reset errno before io calls
+	errno = 0;

 	// assert directory exists
 	if (!ethash_mkdir(dirname)) {
+		ETHASH_CRITICAL("Could not create the ethash directory");
 		goto end;
 	}

 	ethash_io_mutable_name(ETHASH_REVISION, &seedhash, mutable_name);
 	char* tmpfile = ethash_io_create_filename(dirname, mutable_name, strlen(mutable_name));
 	if (!tmpfile) {
+		ETHASH_CRITICAL("Could not create the full DAG pathname");
 		goto end;
 	}

@@ -52,6 +57,7 @@ enum ethash_io_rc ethash_io_prepare(
 			size_t found_size;
 			if (!ethash_file_size(f, &found_size)) {
 				fclose(f);
+				ETHASH_CRITICAL("Could not query size of DAG file: \"%s\"", tmpfile);
 				goto free_memo;
 			}
 			if (file_size != found_size - ETHASH_DAG_MAGIC_NUM_SIZE) {
@@ -64,6 +70,7 @@ enum ethash_io_rc ethash_io_prepare(
 			if (fread(&magic_num, ETHASH_DAG_MAGIC_NUM_SIZE, 1, f) != 1) {
 				// I/O error
 				fclose(f);
+				ETHASH_CRITICAL("Could not read from DAG file: \"%s\"", tmpfile);
 				ret = ETHASH_IO_MEMO_SIZE_MISMATCH;
 				goto free_memo;
 			}
@@ -80,15 +87,25 @@ enum ethash_io_rc ethash_io_prepare(
 	// file does not exist, will need to be created
 	f = ethash_fopen(tmpfile, "wb+");
 	if (!f) {
+		ETHASH_CRITICAL("Could not create DAG file: \"%s\"", tmpfile);
 		goto free_memo;
 	}
 	// make sure it's of the proper size
 	if (fseek(f, (long int)(file_size + ETHASH_DAG_MAGIC_NUM_SIZE - 1), SEEK_SET) != 0) {
 		fclose(f);
+		ETHASH_CRITICAL("Could not seek to the end of DAG file: \"%s\". Insufficient space?", tmpfile);
+		goto free_memo;
+	}
+	if (fputc('\n', f) == EOF) {
+		fclose(f);
+		ETHASH_CRITICAL("Could not write in the end of DAG file: \"%s\". Insufficient space?", tmpfile);
+		goto free_memo;
+	}
+	if (fflush(f) != 0) {
+		fclose(f);
+		ETHASH_CRITICAL("Could not flush at end of DAG file: \"%s\". Insufficient space?", tmpfile);
 		goto free_memo;
 	}
-	fputc('\n', f);
-	fflush(f);
 	ret = ETHASH_IO_MEMO_MISMATCH;
 	goto set_file;

--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io.h
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io.h
@@ -54,6 +54,23 @@ enum ethash_io_rc {
 #define snprintf(...) sprintf_s(__VA_ARGS__)
 #endif

+/**
+ * Logs a critical error in important parts of ethash. Should mostly help
+ * figure out what kind of problem (I/O, memory e.t.c.) causes a NULL
+ * ethash_full_t
+ */
+#ifdef ETHASH_PRINT_CRITICAL_OUTPUT
+#define ETHASH_CRITICAL(...)							\
+	do													\
+	{													\
+		printf("ETHASH CRITICAL ERROR: "__VA_ARGS__);	\
+		printf("\n");									\
+		fflush(stdout);									\
+	} while (0)
+#else
+#define ETHASH_CRITICAL(...)          
+#endif
+
 /**
 * Prepares io for ethash
 *
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io_posix.c
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io_posix.c
@@ -26,6 +26,8 @@
 #include <libgen.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <stdlib.h>
+#include <pwd.h>

 FILE* ethash_fopen(char const* file_name, char const* mode)
 {
@@ -89,6 +91,13 @@ bool ethash_get_default_dirname(char* strbuf, size_t buffsize)
 	static const char dir_suffix[] = ".ethash/";
 	strbuf[0] = '\0';
 	char* home_dir = getenv("HOME");
+	if (!home_dir || strlen(home_dir) == 0)
+	{
+		struct passwd* pwd = getpwuid(getuid());
+		if (pwd)
+			home_dir = pwd->pw_dir;
+	}
+	
 	size_t len = strlen(home_dir);
 	if (!ethash_strncat(strbuf, buffsize, home_dir, len)) {
 		return false;
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io_win32.c
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/src/libethash/io_win32.c
@@ -87,9 +87,9 @@ bool ethash_file_size(FILE* f, size_t* ret_size)

 bool ethash_get_default_dirname(char* strbuf, size_t buffsize)
 {
-	static const char dir_suffix[] = "Appdata\\Ethash\\";
+	static const char dir_suffix[] = "Ethash\\";
 	strbuf[0] = '\0';
-	if (!SUCCEEDED(SHGetFolderPathW(NULL, CSIDL_PROFILE, NULL, 0, (WCHAR*)strbuf))) {
+	if (!SUCCEEDED(SHGetFolderPathA(NULL, CSIDL_LOCAL_APPDATA, NULL, 0, (CHAR*)strbuf))) {
 		return false;
 	}
 	if (!ethash_strncat(strbuf, buffsize, "\\", 1)) {
--- a/Godeps/_workspace/src/github.com/ethereum/ethash/test/c/test.cpp
+++ b/Godeps/_workspace/src/github.com/ethereum/ethash/test/c/test.cpp
@@ -292,12 +292,13 @@ BOOST_AUTO_TEST_CASE(test_ethash_io_memo_file_size_mismatch) {

 BOOST_AUTO_TEST_CASE(test_ethash_get_default_dirname) {
 	char result[256];
-	// this is really not an easy thing to test for in a unit test, so yeah it does look ugly
+	// this is really not an easy thing to test for in a unit test
+	// TODO: Improve this test ...
 #ifdef _WIN32
 	char homedir[256];
-	BOOST_REQUIRE(SUCCEEDED(SHGetFolderPathW(NULL, CSIDL_PROFILE, NULL, 0, (WCHAR*)homedir)));
+	BOOST_REQUIRE(SUCCEEDED(SHGetFolderPathA(NULL, CSIDL_PROFILE, NULL, 0, (CHAR*)homedir)));
 	BOOST_REQUIRE(ethash_get_default_dirname(result, 256));
-	std::string res = std::string(homedir) + std::string("\\Appdata\\Ethash\\");
+	std::string res = std::string(homedir) + std::string("\\AppData\\Local\\Ethash\\");
 #else
 	char* homedir = getenv("HOME");
 	BOOST_REQUIRE(ethash_get_default_dirname(result, 256));
@@ -305,7 +306,7 @@ BOOST_AUTO_TEST_CASE(test_ethash_get_default_dirname) {
 #endif
 	BOOST_CHECK_MESSAGE(strcmp(res.c_str(), result) == 0,
 		"Expected \"" + res + "\" but got \"" + std::string(result) +  "\""
-   );
+	);
 }

 BOOST_AUTO_TEST_CASE(light_and_full_client_checks) {