// Function implementing a FNV inspired hash
// on a string
int main(int argc, const char * argv[]) {
char * str = "Hello, World!";
int buckets = UINT32_MAX;
if (argc > 2) buckets = atoi(argv[2]);
if (argc > 1) str = (char *) argv[1];
printf("Input: %s\nHashed: %u",str,fnv(str,sizeof(str),buckets));
return 0;
}
/// Calculates a full dataset item
///
/// This consist of two 512-bit items produced by calculate_dataset_item_partial().
/// Here the computation is done interleaved for better performance.
hash1024 calculate_dataset_item(const epoch_context& context, uint32_t index) noexcept
{
const hash512* const cache = context.light_cache;
static constexpr size_t num_half_words = sizeof(hash512) / sizeof(uint32_t);
const int64_t num_cache_items = context.light_cache_num_items;
const int64_t index0 = int64_t(index) * 2;
const int64_t index1 = int64_t(index) * 2 + 1;
const uint32_t init0 = static_cast<uint32_t>(index0);
const uint32_t init1 = static_cast<uint32_t>(index1);
hash512 mix0 = cache[index0 % num_cache_items];
hash512 mix1 = cache[index1 % num_cache_items];
mix0.half_words[0] ^= fix_endianness(init0);
mix1.half_words[0] ^= fix_endianness(init1);
// Hash and convert to little-endian 32-bit words.
mix0 = fix_endianness32(keccak512(mix0));
mix1 = fix_endianness32(keccak512(mix1));
for (uint32_t j = 0; j < full_dataset_item_parents; ++j)
{
uint32_t t0 = fnv(init0 ^ j, mix0.half_words[j % num_half_words]);
int64_t parent_index0 = t0 % num_cache_items;
mix0 = fnv(mix0, fix_endianness32(cache[parent_index0]));
uint32_t t1 = fnv(init1 ^ j, mix1.half_words[j % num_half_words]);
int64_t parent_index1 = t1 % num_cache_items;
mix1 = fnv(mix1, fix_endianness32(cache[parent_index1]));
}
// Covert 32-bit words back to bytes and hash.
mix0 = keccak512(fix_endianness32(mix0));
mix1 = keccak512(fix_endianness32(mix1));
return hash1024{{mix0, mix1}};
}
Node CalcDAGItem(const Node *CacheInputNodes, uint32_t NodeCount, uint32_t NodeIdx)
{
Node DAGNode = CacheInputNodes[NodeIdx % NodeCount];
DAGNode.words[0] ^= NodeIdx;
SHA3_512(DAGNode.bytes, DAGNode.bytes, sizeof(Node));
for(uint32_t i = 0; i < 256; ++i) {
uint32_t parent_index = fnv(NodeIdx ^ i, DAGNode.words[i % 16]) % NodeCount;
Node const *parent = CacheInputNodes + parent_index; //&cache_nodes[parent_index];
for(int i = 0; i < 16; ++i) {
DAGNode.words[i] *= FNV_PRIME;
DAGNode.words[i] ^= parent->words[i];
}
}
SHA3_512(DAGNode.bytes, DAGNode.bytes, sizeof(Node));
return DAGNode;
}
static ssize_t do_readv_writev(int type, struct file *file,
const struct iovec __user * uvector,
unsigned long nr_segs, loff_t *pos)
{
typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *);
typedef ssize_t (*iov_fn_t)(struct file *, const struct iovec *, unsigned long, loff_t *);
size_t tot_len;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov=iovstack, *vector;
ssize_t ret;
int seg;
io_fn_t fn;
iov_fn_t fnv;
/*
* SuS says "The readv() function *may* fail if the iovcnt argument
* was less than or equal to 0, or greater than {IOV_MAX}. Linux has
* traditionally returned zero for zero segments, so...
*/
ret = 0;
if (nr_segs == 0)
goto out;
/*
* First get the "struct iovec" from user memory and
* verify all the pointers
*/
ret = -EINVAL;
if (nr_segs > UIO_MAXIOV)
goto out;
if (!file->f_op)
goto out;
if (nr_segs > UIO_FASTIOV) {
ret = -ENOMEM;
iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
if (!iov)
goto out;
}
ret = -EFAULT;
if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector)))
goto out;
/*
* Single unix specification:
* We should -EINVAL if an element length is not >= 0 and fitting an
* ssize_t. The total length is fitting an ssize_t
*
* Be careful here because iov_len is a size_t not an ssize_t
*/
tot_len = 0;
ret = -EINVAL;
for (seg = 0; seg < nr_segs; seg++) {
void __user *buf = iov[seg].iov_base;
ssize_t len = (ssize_t)iov[seg].iov_len;
if (len < 0) /* size_t not fitting an ssize_t .. */
goto out;
if (unlikely(!access_ok(vrfy_dir(type), buf, len)))
goto Efault;
tot_len += len;
if ((ssize_t)tot_len < 0) /* maths overflow on the ssize_t */
goto out;
}
if (tot_len == 0) {
ret = 0;
goto out;
}
ret = rw_verify_area(type, file, pos, tot_len);
if (ret < 0)
goto out;
ret = security_file_permission(file, type == READ ? MAY_READ : MAY_WRITE);
if (ret)
goto out;
fnv = NULL;
if (type == READ) {
fn = file->f_op->read;
fnv = file->f_op->readv;
} else {
fn = (io_fn_t)file->f_op->write;
fnv = file->f_op->writev;
}
if (fnv) {
ret = fnv(file, iov, nr_segs, pos);
goto out;
}
/* Do it by hand, with file-ops */
ret = 0;
vector = iov;
while (nr_segs > 0) {
void __user * base;
size_t len;
ssize_t nr;
base = vector->iov_base;
len = vector->iov_len;
vector++;
nr_segs--;
nr = fn(file, base, len, pos);
if (nr < 0) {
if (!ret) ret = nr;
break;
}
ret += nr;
if (nr != len)
break;
}
out:
if (iov != iovstack)
kfree(iov);
if ((ret + (type == READ)) > 0) {
if (type == READ)
fsnotify_access(file->f_dentry);
else
fsnotify_modify(file->f_dentry);
}
return ret;
Efault:
ret = -EFAULT;
goto out;
}
uint32_t SDHashClass::_incHash(uint32_t hash) {
return fnv((uint8_t*)&hash, sizeof hash, hash);
}
static ssize_t do_readv_writev(int type, struct file *file,
const struct iovec * vector,
unsigned long count)
{
typedef ssize_t (*io_fn_t)(struct file *, char *, size_t, loff_t *);
typedef ssize_t (*iov_fn_t)(struct file *, const struct iovec *, unsigned long, loff_t *);
size_t tot_len;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov=iovstack;
ssize_t ret, i;
io_fn_t fn;
iov_fn_t fnv;
struct inode *inode;
/*
* First get the "struct iovec" from user memory and
* verify all the pointers
*/
ret = 0;
if (!count)
goto out_nofree;
ret = -EINVAL;
if (count > UIO_MAXIOV)
goto out_nofree;
if (!file->f_op)
goto out_nofree;
if (count > UIO_FASTIOV) {
ret = -ENOMEM;
iov = kmalloc(count*sizeof(struct iovec), GFP_KERNEL);
if (!iov)
goto out_nofree;
}
ret = -EFAULT;
if (copy_from_user(iov, vector, count*sizeof(*vector)))
goto out;
/* BSD readv/writev returns EINVAL if one of the iov_len
values < 0 or tot_len overflowed a 32-bit integer. -ink */
tot_len = 0;
ret = -EINVAL;
for (i = 0 ; i < count ; i++) {
size_t tmp = tot_len;
int len = iov[i].iov_len;
if (len < 0)
goto out;
tot_len += len;
if (tot_len < tmp || tot_len < (u32)len)
goto out;
}
inode = file->f_dentry->d_inode;
/* VERIFY_WRITE actually means a read, as we write to user space */
fnv = (type == VERIFY_WRITE ? file->f_op->readv : file->f_op->writev);
if (fnv) {
ret = fnv(file, iov, count, &file->f_pos);
goto out;
}
/* VERIFY_WRITE actually means a read, as we write to user space */
fn = (type == VERIFY_WRITE ? file->f_op->read :
(io_fn_t) file->f_op->write);
ret = 0;
vector = iov;
while (count > 0) {
void * base;
size_t len;
ssize_t nr;
base = vector->iov_base;
len = vector->iov_len;
vector++;
count--;
nr = fn(file, base, len, &file->f_pos);
if (nr < 0) {
if (!ret) ret = nr;
break;
}
ret += nr;
if (nr != len)
break;
}
out:
if (iov != iovstack)
kfree(iov);
out_nofree:
/* VERIFY_WRITE actually means a read, as we write to user space */
return ret;
}
static ssize_t do_readv_writev(int type, struct file *file,
const struct iovec * vector,
unsigned long count)
{
typedef ssize_t (*iov_fn_t)(struct file *, const struct iovec *, unsigned long, loff_t *);
size_t tot_len;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov=iovstack;
ssize_t ret, i;
iov_fn_t fnv;
struct inode *inode;
/*
* First get the "struct iovec" from user memory and
* verify all the pointers
*/
ret = 0;
if (!count)
goto out_nofree;
ret = -EINVAL;
if (count > UIO_MAXIOV)
goto out_nofree;
if (!file->f_op)
goto out_nofree;
if (count > UIO_FASTIOV) {
ret = -ENOMEM;
iov = kmalloc(count*sizeof(struct iovec), GFP_KERNEL);
if (!iov)
goto out_nofree;
}
ret = -EFAULT;
if (copy_from_user(iov, vector, count*sizeof(*vector)))
goto out;
/*
* Single unix specification:
* We should -EINVAL if an element length is not >= 0 and fitting an ssize_t
* The total length is fitting an ssize_t
*
* Be careful here because iov_len is a size_t not an ssize_t
*/
tot_len = 0;
ret = -EINVAL;
for (i = 0 ; i < count ; i++) {
ssize_t len = (ssize_t) iov[i].iov_len;
if (len < 0) /* size_t not fitting an ssize_t .. */
goto out;
tot_len += len;
/* We must do this work unsigned - signed overflow is
undefined and gcc 3.2 now uses that fact sometimes...
FIXME: put in a proper limits.h for each platform */
#if BITS_PER_LONG==64
if (tot_len > 0x7FFFFFFFFFFFFFFFUL)
#else
if (tot_len > 0x7FFFFFFFUL)
#endif
goto out;
}
inode = file->f_dentry->d_inode;
/* VERIFY_WRITE actually means a read, as we write to user space */
ret = locks_verify_area((type == VERIFY_WRITE
? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE),
inode, file, file->f_pos, tot_len);
if (ret) goto out;
fnv = (type == VERIFY_WRITE ? file->f_op->readv : file->f_op->writev);
if (fnv) {
ret = fnv(file, iov, count, &file->f_pos);
goto out;
}
ret = fallback_readv_writev(type == VERIFY_WRITE ? READ : WRITE,
file, iov, count, &file->f_pos);
out:
if (iov != iovstack)
kfree(iov);
out_nofree:
/* VERIFY_WRITE actually means a read, as we write to user space */
if ((ret + (type == VERIFY_WRITE)) > 0)
dnotify_parent(file->f_dentry,
(type == VERIFY_WRITE) ? DN_ACCESS : DN_MODIFY);
return ret;
}
static constexpr IntType fnv(IntType hash, const char* pos) {
return *pos == '\0'
? hash
: fnv((hash * IntType(16777619U)) ^ *pos, (pos+1));
}
std::string getCachedName(const std::string &filename,
const std::string &salt){
//---[ Place Somewhere Else ]-----
char *c_cachePath = getenv("OCCA_CACHE_DIR");
std::string occaCachePath;
if(c_cachePath == NULL){
std::stringstream ss;
#if (OCCA_OS == LINUX_OS) || (OCCA_OS == OSX_OS)
char *c_home = getenv("HOME");
ss << c_home << "/._occa";
std::string defaultCacheDir = ss.str();
mkdir(defaultCacheDir.c_str(), 0755);
#else
char *c_home = getenv("USERPROFILE");
ss << c_home << "\\AppData\\Local\\OCCA";
std::string defaultCacheDir = ss.str();
LPCSTR w_defaultCacheDir = defaultCacheDir.c_str();
BOOL mkdirStatus = CreateDirectoryA(w_defaultCacheDir, NULL);
if(mkdirStatus == FALSE)
assert(GetLastError() == ERROR_ALREADY_EXISTS);
# if OCCA_64_BIT
ss << "\\amd64"; // use different dir's fro 32 and 64 bit
# else
ss << "\\x86"; // use different dir's fro 32 and 64 bit
# endif
defaultCacheDir = ss.str();
w_defaultCacheDir = defaultCacheDir.c_str();
mkdirStatus = CreateDirectoryA(w_defaultCacheDir, NULL);
if(mkdirStatus == FALSE)
assert(GetLastError() == ERROR_ALREADY_EXISTS);
#endif
occaCachePath = defaultCacheDir;
}
else
occaCachePath = c_cachePath;
const int chars = occaCachePath.size();
OCCA_CHECK(chars > 0);
#if (OCCA_OS == LINUX_OS) || (OCCA_OS == OSX_OS)
const char slashChar = '/';
#else
const char slashChar = '\\';
#endif
// Take out the pesky //'s
int pos = 0;
for(int i = 0; i < chars; ++i){
if(occaCachePath[i] == slashChar)
while(i < (chars - 1) && occaCachePath[i + 1] == slashChar)
++i;
occaCachePath[pos++] = occaCachePath[i];
}
if(occaCachePath[pos - 1] != slashChar){
if(pos != chars)
occaCachePath[pos] = slashChar;
else
occaCachePath += slashChar;
}
//================================
const std::string fileContents = readFile(filename);
const std::string contentsSHA = fnv(fileContents + salt);
// Only taking the first 16 characters
return occaCachePath + contentsSHA.substr(0, 16);
}
