c-libp2p/peer/peerstore.c
2017-05-11 13:53:23 -05:00

197 lines
6.1 KiB
C

#include <stdlib.h>
#include <string.h>
#include "libp2p/peer/peerstore.h"
#include "libp2p/utils/logger.h"
struct PeerEntry* libp2p_peer_entry_new() {
struct PeerEntry* out = (struct PeerEntry*)malloc(sizeof(struct PeerEntry));
if (out != NULL) {
out->peer = NULL;
}
return out;
}
void libp2p_peer_entry_free(struct PeerEntry* in) {
if (in != NULL) {
libp2p_peer_free(in->peer);
free(in);
}
}
struct PeerEntry* libp2p_peer_entry_copy(struct PeerEntry* in) {
struct PeerEntry* out = libp2p_peer_entry_new();
if (out != NULL) {
out->peer = libp2p_peer_copy(in->peer);
if (out->peer == NULL) {
free(out);
return NULL;
}
}
return out;
}
/**
* Creates a new empty peerstore
* @param peer_id the peer id as a null terminated string
* @returns an empty peerstore or NULL on error
*/
struct Peerstore* libp2p_peerstore_new(const char* peer_id) {
struct Peerstore* out = (struct Peerstore*)malloc(sizeof(struct Peerstore));
if (out != NULL) {
out->head_entry = NULL;
out->last_entry = NULL;
// now add this peer as the first entry
struct Libp2pPeer* peer = libp2p_peer_new();
peer->connection_type = CONNECTION_TYPE_NOT_CONNECTED;
peer->id_size = strlen(peer_id);
peer->id = malloc(peer->id_size);
memcpy(peer->id, peer_id, peer->id_size);
libp2p_peerstore_add_peer(out, peer);
libp2p_peer_free(peer);
}
return out;
}
/**
* Deallocate resources used by the peerstore
* @param in the struct to deallocate
* @returns true(1) on success, otherwise false(0)
*/
int libp2p_peerstore_free(struct Peerstore* in) {
if (in != NULL) {
struct Libp2pLinkedList* current = in->head_entry;
struct Libp2pLinkedList* next = NULL;
while (current != NULL) {
next = current->next;
libp2p_peer_entry_free((struct PeerEntry*)current->item);
current->item = NULL;
current = next;
}
libp2p_utils_linked_list_free(in->head_entry);
free(in);
}
return 1;
}
/**
* Add a Peer to the Peerstore
* @param peerstore the peerstore to add the entry to
* @param peer_entry the entry to add
* @returns true(1) on success, otherwise false
*/
int libp2p_peerstore_add_peer_entry(struct Peerstore* peerstore, struct PeerEntry* peer_entry) {
struct Libp2pLinkedList* new_item = libp2p_utils_linked_list_new();
if (new_item == NULL)
return 0;
new_item->item = libp2p_peer_entry_copy(peer_entry);
if (new_item->item == NULL) {
libp2p_utils_linked_list_free(new_item);
return 0;
}
if (peerstore->head_entry == NULL) {
peerstore->head_entry = new_item;
peerstore->last_entry = new_item;
} else {
peerstore->last_entry->next = new_item;
peerstore->last_entry = new_item;
}
return 1;
}
/***
* Add a peer to the peerstore
* @param peerstore the peerstore to add the entry to
* @param peer the peer to add (will be wrapped in PeerEntry struct)
* @returns true(1) on success, otherwise false
*/
int libp2p_peerstore_add_peer(struct Peerstore* peerstore, struct Libp2pPeer* peer) {
int retVal = 0;
char* ma_string = "";
if (peer != NULL && peer->addr_head != NULL && peer->addr_head->item != NULL) {
ma_string = ((struct MultiAddress*)peer->addr_head->item)->string;
}
// first check to see if it exists. If it does, return TRUE
if (libp2p_peerstore_get_peer_entry(peerstore, peer->id, peer->id_size) != NULL) {
libp2p_logger_debug("peerstore", "Attempted to add %s to peerstore, but already there.\n", ma_string);
return 1;
}
if (peer->id_size > 0) {
char peer_id[peer->id_size + 1];
memcpy(peer_id, peer->id, peer->id_size);
peer_id[peer->id_size] = 0;
if (peer->addr_head != NULL) {
char* address = ((struct MultiAddress*)peer->addr_head->item)->string;
libp2p_logger_debug("peerstore", "Adding peer %s with address %s to peer store\n", peer_id, address);
}
struct PeerEntry* peer_entry = libp2p_peer_entry_new();
if (peer_entry == NULL) {
return 0;
}
peer_entry->peer = libp2p_peer_copy(peer);
if (peer_entry->peer == NULL)
return 0;
retVal = libp2p_peerstore_add_peer_entry(peerstore, peer_entry);
libp2p_peer_entry_free(peer_entry);
libp2p_logger_debug("peerstore", "Adding peer %s to peerstore was a success\n", peer_id);
}
return retVal;
}
/**
* Retrieve a peer from the peerstore based on the peer id
* @param peerstore the peerstore to search
* @param peer_id the id to search for as a binary array
* @param peer_id_size the size of the binary array
* @returns the PeerEntry struct if found, otherwise NULL
*/
struct PeerEntry* libp2p_peerstore_get_peer_entry(struct Peerstore* peerstore, const unsigned char* peer_id, size_t peer_id_size) {
struct Libp2pLinkedList* current = peerstore->head_entry;
// JMJ Debugging
int count = 0;
while(current != NULL) {
count++;
struct Libp2pPeer* peer = ((struct PeerEntry*)current->item)->peer;
if (peer->id_size == peer_id_size) {
if (memcmp(peer_id, peer->id, peer->id_size) == 0) {
return (struct PeerEntry*)current->item;
}
}
current = current->next;
}
return NULL;
}
/**
* Retrieve a peer from the peerstore based on the peer id
* @param peerstore the peerstore to search
* @param peer_id the id to search for as a binary array
* @param peer_id_size the size of the binary array
* @returns the Peer struct if found, otherwise NULL
*/
struct Libp2pPeer* libp2p_peerstore_get_peer(struct Peerstore* peerstore, const unsigned char* peer_id, size_t peer_id_size) {
struct PeerEntry* entry = libp2p_peerstore_get_peer_entry(peerstore, peer_id, peer_id_size);
if (entry == NULL)
return NULL;
return entry->peer;
}
/**
* Look for this peer in the peerstore. If it is found, return a reference to that object.
* If it is not found, add it, and return a reference to the new copy
* @param peerstore the peerstore to search
* @param in the peer to search for
*/
struct Libp2pPeer* libp2p_peerstore_get_or_add_peer(struct Peerstore* peerstore, struct Libp2pPeer* in) {
struct Libp2pPeer* out = libp2p_peerstore_get_peer(peerstore, (unsigned char*)in->id, in->id_size);
if (out != NULL)
return out;
// we didn't find it. attempt to add
if (!libp2p_peerstore_add_peer(peerstore, in))
return NULL;
return libp2p_peerstore_get_peer(peerstore, (unsigned char*)in->id, in->id_size);
}