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FS-9775: Match up data types with existing code

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colm 2016-12-05 18:59:32 -05:00 committed by Mike Jerris
parent 7ac7a7e75b
commit b51038f618
2 changed files with 1087 additions and 0 deletions
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libs/libks/src/dht/ks_dht_bucket.c Normal file
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/*
* Copyright (c) 2016, Anthony Miiessaly II
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of the original author; nor the names of any contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma GCC optimize ("O0")
#include "ks_dht_bucket.h"
/* change for testing */
#define KS_DHT_BUCKETSIZE 20
/* peer flags */
#define DHTPEER_ACTIVE 0x01
#define DHTPEER_SUSPECT 0x02
#define DHTPEER_EXPIRED 0x04
/* internal structures */
typedef struct ks_dhtrt_bucket_entry_s {
ks_time_t tyme;
unsigned char id[KS_DHT_IDSIZE];
ks_dhtrt_node* gptr; /* ptr to peer */
uint8_t inuse;
uint8_t flags; /* active, suspect, expired */
struct ks_dhtrt_bucket_entry_s* left;
struct ks_dhtrt_bucket_entry_s* right;
struct ks_dhtrt_bucket_entry_s* prev;
} ks_dhtrt_bucket_entry;
typedef struct ks_dhtrt_bucket_s {
ks_dhtrt_bucket_entry entries[KS_DHT_BUCKETSIZE];
ks_dhtrt_bucket_entry* first; /* sorted order - first*/
ks_dhtrt_bucket_entry* last; /* sorted order - last*/
ks_dhtrt_bucket_entry* avail; /* available chain */
unsigned short count;
} ks_dhtrt_bucket;
#define BHF_LEFT 0x80
typedef struct ks_dhtrt_bucket_header {
struct ks_dhtrt_bucket_header* parent;
struct ks_dhtrt_bucket_header* left;
struct ks_dhtrt_bucket_header* right;
ks_dhtrt_bucket* bucket;
unsigned char mask[KS_DHT_IDSIZE];
unsigned char flags;
} ks_dhtrt_bucket_header;
typedef struct ks_dhtrt_internal_s {
ks_dhtrt_bucket_header* buckets;
/* */
} ks_dhtrt_internal;
typedef struct ks_dhtrt_xort_s {
unsigned int ix; /* index of bucket array */
unsigned char xor[KS_DHT_IDSIZE]; /* corresponding xor value */
unsigned int nextix;
} ks_dhtrt_xort;
typedef struct ks_dhtrt_sortedxors_s {
ks_dhtrt_bucket_header* bheader;
ks_dhtrt_xort xort[KS_DHT_BUCKETSIZE];
unsigned char hixor[KS_DHT_IDSIZE];
unsigned int startix;
unsigned int count;
struct ks_dhtrt_sortedxors_s* next;
} ks_dhtrt_sortedxors;
/* --- static functions ---- */
static
ks_dhtrt_bucket_header* ks_dhtrt_create_bucketheader(
ks_pool_t *pool,
ks_dhtrt_bucket_header* parent,
unsigned char* mask);
static
ks_dhtrt_bucket* ks_dhtrt_create_bucket(ks_pool_t* pool);
static
ks_dhtrt_bucket_header* ks_dhtrt_find_bucketheader(ks_dhtrt_routetable* table, unsigned char* id);
static
ks_dhtrt_bucket_entry* ks_dhtrt_find_bucketentry(ks_dhtrt_bucket_header* header, ks_dhtrt_nodeid id);
static
void ks_dhtrt_split_bucket(ks_dhtrt_bucket_header* original, ks_dhtrt_bucket_header* left, ks_dhtrt_bucket_header* right);
static
ks_dht_node_t* ks_dhtrt_find_nodeid(ks_dhtrt_bucket* bucket, ks_dhtrt_nodeid nodeid);
static void
ks_dhtrt_shiftright(unsigned char* id);
static
void ks_dhtrt_shiftleft(unsigned char* id);
static int
ks_dhtrt_xorcmp(const unsigned char *id1, const unsigned char *id2, const unsigned char *ref);
static void
ks_dhtrt_xor(const unsigned char *id1, const unsigned char *id2, unsigned char *xor);
static int
ks_dhtrt_ismasked(const unsigned char *id1, const unsigned char *mask);
static
ks_status_t ks_dhtrt_insert_node(ks_dhtrt_routetable* table, ks_dhtrt_node* node);
static
ks_status_t ks_dhtrt_insert_id(ks_dhtrt_bucket* bucket, ks_dhtrt_node* node);
static
void ks_dhtrt_delete_id(ks_dhtrt_bucket* bucket, ks_dhtrt_nodeid id);
static
char* ks_dhtrt_printableid(const unsigned char* id, char* buffer);
static
unsigned char ks_dhtrt_isactive(ks_dhtrt_bucket_entry* entry);
static
uint8_t ks_dhtrt_load_query(ks_dhtrt_querynodes* query, ks_dhtrt_sortedxors* xort);
static
uint8_t ks_dhtrt_findclosest_bucketnodes(unsigned char *nodeid,
ks_dhtrt_bucket_header* header,
ks_dhtrt_sortedxors* xors,
unsigned char* hixor,
unsigned int max);
/* debugging */
#define KS_DHT_DEBUGPRINTF_
/*
Public interface
---------------
ks_dhtrt_initroute
ks_dhtrt_drinitroute
ks_dhtrt_insertnode
*/
KS_DECLARE(ks_dhtrt_routetable*) ks_dhtrt_initroute( ks_pool_t *pool, ks_dhtrt_nodeid localid)
{
ks_log(KS_LOG_ERROR, "hello world\n");
unsigned char initmask[KS_DHT_IDSIZE];
memset(initmask, 0xff, sizeof(initmask));
ks_dhtrt_routetable* table = ks_pool_alloc(pool, sizeof(ks_dhtrt_routetable));
memset(table, 0, sizeof(ks_dhtrt_routetable));
ks_dhtrt_internal* internal = ks_pool_alloc(pool, sizeof(ks_dhtrt_internal));
memset(internal, 0, sizeof(ks_dhtrt_internal));
table->internal = internal;
/* initialize root bucket */
ks_dhtrt_bucket_header* initial_header = ks_dhtrt_create_bucketheader(pool, 0, initmask);
initial_header->flags = BHF_LEFT; /* fake left to allow splitting */
internal->buckets = initial_header;
initial_header->bucket = ks_dhtrt_create_bucket(pool);
table->pool = pool;
return table;
}
KS_DECLARE(void) ks_dhtrt_deinitroute( ks_dhtrt_routetable* table )
{
/*todo*/
ks_pool_free(table->pool, table);
return;
}
KS_DECLARE(ks_dhtrt_node*) ks_dhtrt_create_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid, ks_dht_node_t* node)
{
/* first see if it exists */
ks_dhtrt_node* peer = ks_dhtrt_find_node(table, nodeid);
if (peer != 0) { /* humm not sure - this might be an error */
return peer;
}
peer = ks_pool_alloc(table->pool, sizeof(ks_dhtrt_node));
memset(peer, 0, sizeof(ks_dhtrt_node));
memcpy(peer->id, nodeid, KS_DHT_IDSIZE);
ks_status_t status = ks_dhtrt_insert_node(table, peer);
if (status == KS_STATUS_FAIL) {
ks_pool_free(table->pool, peer);
return 0;
}
peer->handle = node;
return peer;
}
KS_DECLARE(ks_status_t) ks_dhtrt_delete_node(ks_dhtrt_routetable* table, ks_dhtrt_node* peer)
{
ks_dhtrt_bucket_header* header = ks_dhtrt_find_bucketheader(table, peer->id);
if (header != 0) {
ks_dhtrt_bucket* bucket = header->bucket;
if (bucket != 0) { /* we were not able to find a bucket*/
ks_dhtrt_delete_id(bucket, peer->id);
}
}
ks_pool_free(table->pool, peer);
return KS_STATUS_SUCCESS;
}
KS_DECLARE(ks_status_t) ks_dhtrt_insert_node(ks_dhtrt_routetable* table, ks_dhtrt_node* peer)
{
ks_dhtrt_bucket* bucket = 0;
int insanity = 0;
ks_dhtrt_bucket_header* header = ks_dhtrt_find_bucketheader(table, peer->id);
bucket = header->bucket;
assert(bucket != 0); /* we were not able to find a bucket*/
while (bucket->count == KS_DHT_BUCKETSIZE) {
if (insanity > 3200) assert(insanity < 3200);
/* first - seek a stale entry to eject */
/*
todo: attempting a ping at at this point would require us
to suspend this process ... tricky...assume right now we will go ahead and
eject. Possibly add to a list to recheck
*/
if ( !(header->flags & BHF_LEFT) ) { /* only the left handside node can be split */
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf(" nodeid %s was not inserted\n", ks_dhtrt_printableid(peer->id, buffer));
#endif
return KS_STATUS_FAIL;
}
/* bucket must be split */
/* work out new mask */
unsigned char newmask[KS_DHT_IDSIZE];
memcpy(newmask, header->mask, KS_DHT_IDSIZE);
if (newmask[KS_DHT_IDSIZE-1] == 0) { /* no more bits to shift - is this possible */
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf(" nodeid %s was not inserted\n", ks_dhtrt_printableid(peer->id, buffer));
#endif
return KS_STATUS_FAIL;
}
/* shift right x bits : todo 1 bit for the moment */
ks_dhtrt_shiftright(newmask);
/* create the new bucket structures */
ks_dhtrt_bucket_header* newleft = ks_dhtrt_create_bucketheader(table->pool, header, newmask);
newleft->bucket = ks_dhtrt_create_bucket(table->pool);
newleft->flags = BHF_LEFT; /* flag as left hand side - therefore splitable */
ks_dhtrt_bucket_header* newright = ks_dhtrt_create_bucketheader(table->pool, header, header->mask);
ks_dhtrt_split_bucket(header, newleft, newright);
/* ok now we need to try again to see if the bucket has capacity */
/* which bucket do care about */
if (ks_dhtrt_ismasked(peer->id, newleft->mask)) {
bucket = newleft->bucket;
header = newleft;
}
else {
bucket = newright->bucket;
header = newright;
}
++insanity;
}
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("inserting nodeid %s ", ks_dhtrt_printableid(peer->id, buffer));
printf("into bucket %s\n", ks_dhtrt_printableid(header->mask, buffer));
#endif
/* by this point we have a viable bucket */
return ks_dhtrt_insert_id(bucket, peer);
}
KS_DECLARE(ks_dht_node_t*) ks_dhtrt_find_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid) {
ks_dhtrt_bucket_header* header = ks_dhtrt_find_bucketheader(table, nodeid);
if (header != 0) return 0;
ks_dhtrt_bucket* bucket = header->bucket;
if (bucket != 0) return 0; /* probably a logic error ?*/
return ks_dhtrt_find_nodeid(bucket, nodeid);
}
KS_DECLARE(ks_status_t) ks_dhtrt_touch_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid)
{
ks_dhtrt_bucket_header* header = ks_dhtrt_find_bucketheader(table, nodeid);
if (header == 0) return KS_STATUS_FAIL;
ks_dhtrt_bucket_entry* e = ks_dhtrt_find_bucketentry(header, nodeid);
if (e != 0) {
e->tyme = ks_time_now();
e->flags = DHTPEER_ACTIVE;
return KS_STATUS_SUCCESS;
}
return KS_STATUS_FAIL;
}
KS_DECLARE(ks_status_t) ks_dhtrt_expire_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid)
{
ks_dhtrt_bucket_header* header = ks_dhtrt_find_bucketheader(table, nodeid);
if (header == 0) return KS_STATUS_FAIL;
ks_dhtrt_bucket_entry* e = ks_dhtrt_find_bucketentry(header, nodeid);
if (e != 0) {
e->flags = DHTPEER_EXPIRED;
return KS_STATUS_SUCCESS;
}
return KS_STATUS_FAIL;
}
KS_DECLARE(uint8_t) ks_dhtrt_findclosest_nodes(ks_dhtrt_routetable* table, ks_dhtrt_querynodes* query)
{
query->count = 0;
uint8_t max = query->max;
uint8_t total = 0;
uint8_t cnt;
if (max == 0) return 0; /* sanity check */
ks_dhtrt_bucket_header* header = ks_dhtrt_find_bucketheader(table, query->id);
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("finding %d closest nodes for nodeid %s\n", max, ks_dhtrt_printableid(query->id, buffer));
printf(" starting at mask: %s\n", ks_dhtrt_printableid(header->mask, buffer));
#endif
ks_dhtrt_sortedxors xort0;
memset(&xort0, 0 , sizeof(xort0));
ks_dhtrt_nodeid initid;
memset(initid, 0xff, KS_DHT_IDSIZE);
xort0.bheader = header;
/* step 1 - look at immediate bucket */
/* --------------------------------- */
cnt = ks_dhtrt_findclosest_bucketnodes(query->id, header, &xort0, initid ,max);
max -= cnt;
total += cnt;
#ifdef KS_DHT_DEBUGPRINTF_
printf(" bucket header %s yielded %d nodes; total=%d\n", buffer, cnt, total);
#endif
if (total >= query->max) { /* is query answered ? */
return ks_dhtrt_load_query(query, &xort0);
}
/* step2 - look at sibling */
/* ----------------------- */
ks_dhtrt_sortedxors xort1;
xort0.next = &xort1;
memset(&xort1, 0 , sizeof(xort1));
memcpy(initid, &xort0.hixor, KS_DHT_IDSIZE);
ks_dhtrt_bucket_header* parent = header->parent;
if (header == parent->left) {
xort1.bheader = header = parent->right;
}
else {
if (!parent->left->bucket) { /* left hand might no have a bucket - if so choose left->right */
xort1.bheader = header = parent->left->right;
}
else {
xort1.bheader = header = parent->left;
}
}
cnt = ks_dhtrt_findclosest_bucketnodes(query->id, header, &xort1, initid ,max);
max -= cnt;
total += cnt;
#ifdef KS_DHT_DEBUGPRINTF_
printf(" stage2: sibling bucket header %s yielded %d nodes, total=%d\n",
ks_dhtrt_printableid(header->mask, buffer), cnt, total);
#endif
if (total >= query->max) { /* is query answered ? */
return ks_dhtrt_load_query(query, &xort0);
}
/* step3 and beyond ... work left and right until the count is satisfied */
/* ---------------------------------------------------------------------- */
memcpy(initid, &xort0.hixor, KS_DHT_IDSIZE);
unsigned char leftid[KS_DHT_IDSIZE];
unsigned char rightid[KS_DHT_IDSIZE];
memcpy(leftid, xort0.bheader->mask, KS_DHT_IDSIZE);
memcpy(rightid, xort1.bheader->mask, KS_DHT_IDSIZE);
int insanity = 0;
ks_dhtrt_bucket_header* lheader;
ks_dhtrt_bucket_header* rheader;
ks_dhtrt_sortedxors* prev = &xort1;
ks_dhtrt_sortedxors* tofree = 0;
ks_dhtrt_sortedxors* xortn;
ks_dhtrt_sortedxors* xortn1;
do {
lheader = 0;
rheader = 0;
xortn = 0;
xortn1 = 0;
if (leftid[0] != 0xff) {
ks_dhtrt_shiftleft(leftid);
lheader = ks_dhtrt_find_bucketheader(table, leftid);
if (lheader) {
xortn = ks_pool_alloc(table->pool, sizeof(ks_dhtrt_sortedxors));
memset(xortn, 0, sizeof(ks_dhtrt_sortedxors));
if (tofree == 0) tofree = xortn;
prev->next = xortn;
prev = xortn;
cnt += ks_dhtrt_findclosest_bucketnodes(query->id, lheader, xortn, leftid ,max);
max -= cnt;
#ifdef KS_DHT_DEBUGPRINTF_
printf(" stage3: seaching left bucket header %s yielded %d nodes, total=%d\n",
ks_dhtrt_printableid(lheader->mask, buffer), cnt, total);
#endif
}
}
if (max > 0 && rightid[KS_DHT_IDSIZE-1] != 0x00) {
ks_dhtrt_shiftright(rightid);
rheader = ks_dhtrt_find_bucketheader(table, rightid);
if (rheader) {
xortn1 = ks_pool_alloc(table->pool, sizeof(ks_dhtrt_sortedxors));
memset(xortn1, 0, sizeof(ks_dhtrt_sortedxors));
prev->next = xortn1;
prev = xortn1;
cnt = ks_dhtrt_findclosest_bucketnodes(query->id, rheader, xortn1, rightid , max);
max -= cnt;
#ifdef KS_DHT_DEBUGPRINTF_
printf(" stage3: seaching right bucket header %s yielded %d nodes, total=%d\n",
ks_dhtrt_printableid(rheader->mask, buffer), cnt, total);
#endif
}
}
if (!lheader && !rheader) break;
++insanity;
if (insanity > 159) {
assert(insanity <= 159);
}
} while(max < query->count);
ks_dhtrt_load_query(query, &xort0);
/* free up the xort structs on heap */
while(tofree) {
ks_dhtrt_sortedxors* x = tofree->next;
ks_pool_free(table->pool, tofree);
tofree = x->next;
}
return query->count;
}
KS_DECLARE(void) ks_dhtrt_process_table(ks_dhtrt_routetable* table)
{
/* walk the table and update the status of all known knodes */
/* anything that is suspect automatically becomes expired */
/* inactive for 15 minutes, a node becomes quesionable */
/* it should be pinged */
/* if it has not been 'touched' since the last time */
/* give it one more try */
/* inactive again it is considered inactive */
/* */
ks_dhtrt_internal* internal = table->internal;
ks_dhtrt_bucket_header* header = internal->buckets;
ks_dhtrt_bucket_header* stack[KS_DHT_IDSIZE * 8];
int stackix=0;
while(header) {
stack[stackix++] = header;
if (header->bucket) {
/*ks_dhtrt_bucket* b = header->bucket;*/
for (int ix=0; ix<KS_DHT_BUCKETSIZE; ++ix) {
}
}
header = header->left;
if (header == 0 && stackix > 1) {
stackix -= 2;
header = stack[stackix];
header = header->right;
}
}
}
KS_DECLARE(void) ks_dhtrt_dump(ks_dhtrt_routetable* table, int level) {
/* dump buffer headers */
char buffer[100];
memset(buffer, 0, 100);
ks_dhtrt_internal* internal = table->internal;
ks_dhtrt_bucket_header* header = internal->buckets;
ks_dhtrt_bucket_header* stack[KS_DHT_IDSIZE * 8];
int stackix = 0;
while(header) {
stack[stackix++] = header;
/* walk and report left handsize */
memset(buffer, 0, 100);
/*ks_log*/ printf("bucket header: [%s]\n", ks_dhtrt_printableid(header->mask, buffer) );
if (header->bucket) {
ks_dhtrt_bucket* b = header->bucket;
printf(" bucket holds %d entries\n", b->count);
if (level == 7) {
printf(" --------------------------\n");
for(int ix=0; ix<KS_DHT_BUCKETSIZE; ++ix) {
memset(buffer, 0, 100);
if (b->entries[ix].inuse == 1) ks_dhtrt_printableid(b->entries[ix].id, buffer);
else strcpy(buffer, "<free>");
printf(" slot %d: %s\n", ix, buffer);
}
printf(" --------------------------\n\n");
}
}
header = header->left;
if (header == 0 && stackix > 1) {
stackix -= 2;
header = stack[stackix];
header = header->right;
}
}
return;
}
/* stupid routines to avoid unused warnings */
void colm() {
ks_dhtrt_shiftright(0);
ks_dhtrt_xor(0, 0, 0);
ks_dhtrt_xorcmp(0, 0, 0);
ks_dhtrt_split_bucket(0, 0, 0);
ks_dhtrt_shiftleft(0);
}
/*
internal functions
*/
static
ks_dhtrt_bucket_header* ks_dhtrt_create_bucketheader(ks_pool_t *pool, ks_dhtrt_bucket_header* parent, unsigned char* mask)
{
ks_dhtrt_bucket_header* header = ks_pool_alloc(pool, sizeof(ks_dhtrt_bucket_header));
memset(header, 0, sizeof(ks_dhtrt_bucket_header));
memcpy(header->mask, mask, sizeof(header->mask));
header->parent = parent;
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("creating bucket header for mask: %s ", ks_dhtrt_printableid(mask, buffer));
if (parent) printf("from parent mask: %s ", ks_dhtrt_printableid(parent->mask, buffer));
printf("\n");
#endif
return header;
}
static
ks_dhtrt_bucket* ks_dhtrt_create_bucket(ks_pool_t *pool)
{
ks_dhtrt_bucket* bucket = ks_pool_alloc(pool, sizeof(ks_dhtrt_bucket));
memset(bucket, 0, sizeof(ks_dhtrt_bucket));
return bucket;
}
static
ks_dhtrt_bucket_header* ks_dhtrt_find_bucketheader(ks_dhtrt_routetable* table, unsigned char* id)
{
/* find the right bucket.
if a bucket header has a bucket, it does not children
so it must be the bucket to use
*/
ks_dhtrt_internal* internal = table->internal;
ks_dhtrt_bucket_header* header = internal->buckets;
while(header) {
if ( header->bucket ) {
return header;
}
/* left hand side is more restrictive (closer) so should be tried first */
if (header->left != 0 && (ks_dhtrt_ismasked(id, header->left->mask)))
header = header->left;
else
header = header->right;
}
return 0;
}
static
ks_dhtrt_bucket_entry* ks_dhtrt_find_bucketentry(ks_dhtrt_bucket_header* header, ks_dhtrt_nodeid nodeid)
{
ks_dhtrt_bucket* bucket = header->bucket;
if (bucket == 0) return 0;
for (int ix=0; ix<KS_DHT_BUCKETSIZE; ++ix) {
#ifdef KS_DHT_DEBUGPRINTF_
#endif
if ( bucket->entries[ix].inuse == 1 &&
(!memcmp(nodeid, bucket->entries[ix].id, KS_DHT_IDSIZE)) ) {
return &(bucket->entries[ix]);
}
}
return 0;
}
static
void ks_dhtrt_split_bucket(ks_dhtrt_bucket_header* original, ks_dhtrt_bucket_header* left, ks_dhtrt_bucket_header* right)
{
/* so split the bucket in two based on the masks in the new header */
/* the existing bucket - with the remaining ids will be taken by the right hand side */
ks_dhtrt_bucket* source = original->bucket;
ks_dhtrt_bucket* dest = left->bucket;
int lix = 0;
int rix = 0;
for( ; rix<KS_DHT_BUCKETSIZE; ++rix) {
if (ks_dhtrt_ismasked(source->entries[rix].id, left->mask)) {
/* move it to the left */
memcpy(dest->entries[lix].id, source->entries[rix].id, KS_DHT_IDSIZE);
dest->entries[lix].gptr = source->entries[rix].gptr;
dest->entries[lix].inuse = 1;
++lix;
++dest->count;
/* now remove it from the original bucket */
source->entries[rix].inuse = 0;
--source->count;
}
}
/* give original bucket to the new left hand side header */
right->bucket = source;
original->bucket = 0;
original->left = left;
original->right = right;
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("\nsplitting bucket orginal: %s\n", ks_dhtrt_printableid(original->mask, buffer));
printf(" into (left) mask: %s size: %d\n", ks_dhtrt_printableid(left->mask, buffer), left->bucket->count);
printf(" and (right) mask: %s size: %d\n\n", ks_dhtrt_printableid(right->mask, buffer), right->bucket->count);
#endif
return;
}
/*
* buckets are implemented as static array
* There does not seem to be any advantage in sorting/tree structures in terms of xor math
* so at least the static array does away with the need for locking.
*/
static
ks_status_t ks_dhtrt_insert_id(ks_dhtrt_bucket* bucket, ks_dhtrt_node* peer)
{
/* sanity checks */
if (!bucket || bucket->count >= KS_DHT_BUCKETSIZE) {
assert(0);
}
uint8_t free = KS_DHT_BUCKETSIZE;
/* find free .. but also check that it is not already here! */
uint8_t ix = 0;
for(; ix<KS_DHT_BUCKETSIZE; ++ix) {
if (bucket->entries[ix].inuse == 0) {
if (free == KS_DHT_BUCKETSIZE) {
free = ix; /* use this one */
}
}
else if (!memcmp(bucket->entries[ix].id, peer->id, KS_DHT_IDSIZE)) {
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("duplicate peer %s found at %d ", ks_dhtrt_printableid(peer->id, buffer), ix);
#endif
bucket->entries[ix].tyme = ks_time_now();
bucket->entries[ix].flags &= DHTPEER_ACTIVE;
return KS_STATUS_SUCCESS; /* already exists */
}
}
if ( free<KS_DHT_BUCKETSIZE ) {
bucket->entries[free].inuse = 1;
bucket->entries[free].gptr = peer;
bucket->entries[free].tyme = ks_time_now();
bucket->entries[free].flags &= DHTPEER_ACTIVE;
++bucket->count;
memcpy(bucket->entries[free].id, peer->id, KS_DHT_IDSIZE);
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("inserting peer %s ", ks_dhtrt_printableid(peer->id, buffer));
printf("into bucket mask at index %d\n", free);
#endif
return KS_STATUS_SUCCESS;
}
assert(0); /* should not reach this point */
return KS_STATUS_FAIL;
}
static
ks_dht_node_t* ks_dhtrt_find_nodeid(ks_dhtrt_bucket* bucket, ks_dhtrt_nodeid nodeid)
{
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("\nfind noeid for: %s\n", ks_dhtrt_printableid(nodeid, buffer));
#endif
for (int ix=0; ix<KS_DHT_BUCKETSIZE; ++ix) {
#ifdef KS_DHT_DEBUGPRINTF_
printf("\nbucket->entries[%d].id = %s inuse=%c\n", ix,
ks_dhtrt_printableid(bucket->entries[ix].id, buffer),
bucket->entries[ix].inuse );
#endif
if ( bucket->entries[ix].inuse == 1 &&
(!memcmp(nodeid, bucket->entries[ix].id, KS_DHT_IDSIZE)) ) {
return bucket->entries[ix].gptr->handle;
}
}
return 0;
}
static
void ks_dhtrt_delete_id(ks_dhtrt_bucket* bucket, ks_dhtrt_nodeid nodeid)
{
#ifdef KS_DHT_DEBUGPRINTF_
char buffer[100];
printf("\ndeleting node for: %s\n", ks_dhtrt_printableid(nodeid, buffer));
#endif
for (int ix=0; ix<KS_DHT_BUCKETSIZE; ++ix) {
#ifdef KS_DHT_DEBUGPRINTF_
printf("\nbucket->entries[%d].id = %s inuse=%c\n", ix,
ks_dhtrt_printableid(bucket->entries[ix].id, buffer),
bucket->entries[ix].inuse );
#endif
if ( bucket->entries[ix].inuse == 1 &&
(!memcmp(nodeid, bucket->entries[ix].id, KS_DHT_IDSIZE)) ) {
bucket->entries[ix].inuse = 0;
bucket->entries[ix].gptr = 0;
bucket->entries[ix].flags = 0;
return;
}
}
return;
}
static
uint8_t ks_dhtrt_findclosest_bucketnodes(unsigned char *nodeid,
ks_dhtrt_bucket_header* header,
ks_dhtrt_sortedxors* xors,
unsigned char* hixor, /*todo: remove */
unsigned int max) {
uint8_t count = 0; /* count of nodes added this time */
xors->startix = KS_DHT_BUCKETSIZE;
xors->count = 0;
unsigned char xorvalue[KS_DHT_IDSIZE];
/* just ugh! - there must be a better way to do this */
/* walk the entire bucket calculating the xor value on the way */
/* add valid & relevant entries to the xor values */
ks_dhtrt_bucket* bucket = header->bucket;
if (bucket == 0) { /* sanity */
#ifdef KS_DHT_DEBUGPRINTF_
char buf[100];
printf("closestbucketnodes: intermediate tree node found %s\n",
ks_dhtrt_printableid(header->mask, buf));
#endif
}
for(uint8_t ix=0; ix<KS_DHT_BUCKETSIZE; ++ix) {
if ( bucket->entries[ix].inuse == 1 &&
ks_dhtrt_isactive( &(bucket->entries[ix])) ) {
/* calculate xor value */
ks_dhtrt_xor(nodeid, bucket->entries[ix].id, xorvalue );
/* do we need to hold this one */
if ( count < max || /* yes: we have not filled the quota yet */
(memcmp(xorvalue, hixor, KS_DHT_IDSIZE) < 0)) { /* or is closer node than one already selected */
/* now sort the new xorvalue into the results structure */
/* this now becomes worst case O(n*2) logic - is there a better way */
/* in practice the bucket size is fixed so actual behavior is proably 0(logn) */
unsigned int xorix = xors->startix; /* start of ordered list */
unsigned int prev_xorix = KS_DHT_BUCKETSIZE;
for(int ix2=0; ix2<count; ++ix2) {
if (memcmp(xorvalue, xors->xort[xorix].xor, KS_DHT_IDSIZE) > 0) {
break; /* insert before xorix, after prev_xoris */
}
prev_xorix = xorix;
xorix = xors->xort[xorix].nextix;
}
/* insert point found
count -> array slot to added newly identified node
insert_point -> the array slot before which we need to insert the newly identified node
*/
memcpy(xors->xort[count].xor, xorvalue, KS_DHT_IDSIZE);
xors->xort[count].ix = ix;
xors->xort[count].nextix = xorix; /* correct forward chain */
if (prev_xorix < KS_DHT_BUCKETSIZE) { /* correct backward chain */
xors->xort[prev_xorix].nextix = count;
}
else {
xors->startix = count;
}
++count;
}
}
}
xors->count = count;
return count; /* return count of added nodes */
}
static
uint8_t ks_dhtrt_load_query(ks_dhtrt_querynodes* query, ks_dhtrt_sortedxors* xort)
{
ks_dhtrt_sortedxors* current = xort;
uint8_t loaded = 0;
while(current) {
#ifdef KS_DHT_DEBUGPRINTF_
char buf[100];
printf(" loadquery from bucket %s count %d\n",
ks_dhtrt_printableid(current->bheader->mask,buf), current->count);
#endif
int xorix = current->startix;
for (uint8_t ix = 0; ix<= current->count && loaded < query->max; ++ix ) {
unsigned int z = current->xort[xorix].ix;
query->nodes[ix] = current->bheader->bucket->entries[z].gptr->handle;
++loaded;
}
if (loaded >= query->max) break;
current = current->next;
}
query->count = loaded;
return loaded;
}
/*
strictly for shifting the bucketheader mask
so format must be a right filled mask (hex: ..ffffffff)
*/
static
void ks_dhtrt_shiftright(unsigned char* id)
{
unsigned char b0 = 0;
unsigned char b1 = 0;
for(int i = KS_DHT_IDSIZE-1; i >= 0; --i) {
if (id[i] == 0) break; /* beyond mask- we are done */
b1 = id[i] & 0x01;
id[i] >>= 1;
if (i != (KS_DHT_IDSIZE-1)) {
id[i+1] |= (b0 << 7);
}
b0 = b1;
}
return;
}
static
void ks_dhtrt_shiftleft(unsigned char* id) {
for(int i = KS_DHT_IDSIZE-1; i >= 0; --i) {
if (id[i] == 0xff) continue;
id[i] <<= 1;
id[i] |= 0x01;
break;
}
return;
}
/* Determine whether id1 or id2 is closer to ref */
static int ks_dhtrt_xorcmp(const unsigned char *id1, const unsigned char *id2, const unsigned char *ref)
{
int i;
for (i = 0; i < KS_DHT_IDSIZE; i++) {
unsigned char xor1, xor2;
if (id1[i] == id2[i]) {
continue;
}
xor1 = id1[i] ^ ref[i];
xor2 = id2[i] ^ ref[i];
if (xor1 < xor2) {
return -1; /* id1 is closer */
}
return 1; /* id2 is closer */
}
return 0; /* id2 and id2 are identical ! */
}
/* create an xor value from two ids */
static void ks_dhtrt_xor(const unsigned char *id1, const unsigned char *id2, unsigned char *xor)
{
for (int i = 0; i < KS_DHT_IDSIZE; ++i) {
if (id1[i] == id2[i]) {
xor[i] = 0;
}
xor[i] = id1[i] ^ id2[i];
}
return;
}
/* is id masked by mask 1 => yes, 0=> no */
static int ks_dhtrt_ismasked(const unsigned char *id, const unsigned char *mask)
{
for (int i = 0; i < KS_DHT_IDSIZE; ++i) {
if (mask[i] == 0 && id[i] != 0) return 0;
else if (mask[i] == 0xff) return 1;
else if (id[i] > mask[i]) return 0;
}
return 1;
}
static char* ks_dhtrt_printableid(const unsigned char* id, char* buffer)
{
char* t = buffer;
memset(buffer, 0, KS_DHT_IDSIZE*2);
for (int i = 0; i < KS_DHT_IDSIZE; ++i, buffer+=2) {
sprintf(buffer, "%02x", id[i]);
}
return t;
}
unsigned char ks_dhtrt_isactive(ks_dhtrt_bucket_entry* entry)
{
/* todo */
return 1;
}

108
libs/libks/src/dht/ks_dht_bucket.h Normal file
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/*
* Copyright (c) 2016 Colm Quinn
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of the original author; nor the names of any contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _KS_DHT_BUCKETS_H_
#define _KS_DHT_BUCKETS_H_
#ifdef __cplusplus
#define KS_BEGIN_EXTERN_C extern "C" {
#define KS_END_EXTERN_C }
#else
#define KS_BEGIN_EXTERN_C
#define KS_END_EXTERN_C
#endif
#include "ks.h"
KS_BEGIN_EXTERN_C
/* @todo: temporary - replace with real definiton when available */
typedef void ks_dht_node_t;
enum ks_dhtrt_nodestate_t {DHTRT_UNKNOWN, DHTRT_ACTIVE, DHTRT_SUSPECT, DHTRT_EXPIRED};
typedef ks_status_t (*ks_dhtrt_callback)(ks_dht_node_t*, enum ks_dhtrt_nodestate_t);
/* for testing */
#define KS_DHT_BUCKETSIZE 20
#define KS_DHT_IDSIZE 20
typedef struct ks_dhtrt_node_s {
unsigned char id[KS_DHT_IDSIZE];
ks_dht_node_t* handle;
} ks_dhtrt_node;
typedef struct ks_dhtrt_routetable_s {
void* internal; /* ks_dhtrt_internal */
ks_pool_t* pool; /* */
ks_logger_t logger;
} ks_dhtrt_routetable;
typedef struct ks_dhtrt_querynodes_s {
unsigned char id[KS_DHT_IDSIZE]; /* in: id to query */
uint8_t max; /* in: maximum to return */
uint8_t count; /* out: number returned */
ks_dht_node_t* nodes[KS_DHT_BUCKETSIZE]; /* out: array of peers (ks_dht_node_t* peer[incount]) */
} ks_dhtrt_querynodes;
typedef unsigned char ks_dhtrt_nodeid[KS_DHT_IDSIZE];
/* methods */
ks_dhtrt_routetable* ks_dhtrt_initroute( ks_pool_t *pool, ks_dhtrt_nodeid localid);
ks_status_t ks_dhtrt_registercallback(ks_dhtrt_callback, enum ks_dhtrt_nodestate_t);
void ks_dhtrt_deinitroute(ks_dhtrt_routetable* table );
ks_dhtrt_node* ks_dhtrt_create_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid, ks_dht_node_t* node);
ks_status_t ks_dhtrt_delete_node(ks_dhtrt_routetable* table, ks_dhtrt_node* node);
ks_status_t ks_dhtrt_touch_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid);
ks_status_t ks_dhtrt_expire_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid nodeid);
uint8_t ks_dhtrt_findclosest_nodes(ks_dhtrt_routetable* table, ks_dhtrt_querynodes* query);
ks_dht_node_t* ks_dhtrt_find_node(ks_dhtrt_routetable* table, ks_dhtrt_nodeid id);
/* debugging aids */
void ks_dhtrt_dump(ks_dhtrt_routetable* table, int level);
void ks_dhtrt_process_table(ks_dhtrt_routetable* table);
KS_END_EXTERN_C
#endif