+++ /dev/null
-/*******************************************************************************
-* dht.c
-*
-* High-performance Distributed Hash Table for finding the location of objects
-* in a Distributed Shared Transactional Memory system.
-*
-* Creator: Erik Rubow
-*
-* TODO:
-* 1) Instead of having dhtInsertMult, dhtSearchMult, etc. call their single-key
-* counterparts repeatedly, define some new messages to handle it more
-* efficiently.
-* 2) Improve the efficiency of functions that work with hostArray, hostReplied,
-* and blockOwnerArray.
-* 3) Currently a join or leave causes a rebuild of the entire hash table.
-* Implement more graceful join and leave procedures.
-* 4) Fine tune timeout values for performance, possibly implement a backoff
-* algorithm to prevent overloading the network.
-* 5) Whatever else I'm forgetting
-*
-*******************************************************************************/
-/*******************************************************************************
-* Includes
-*******************************************************************************/
-
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/ioctl.h>
-#include <stdio.h>
-#include <stdarg.h>
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <pthread.h>
-#include <sys/time.h>
-#include <sys/poll.h>
-#include <netdb.h>
-#include <net/if.h>
-#include <linux/sockios.h>
-#include <sys/queue.h>
-#include "dht.h"
-#include "clookup.h" //this works for now, do we need anything better?
-#include "mlookup.h"
-
-/*******************************************************************************
-* Local Defines, Structs
-*******************************************************************************/
-
-#define MAX_MSG_SIZE 1500
-#define UDP_PORT 2157
-#define INIT_HOST_ALLOC 3
-#define INIT_NUM_BLOCKS 16
-#define DEFAULT_INTERFACE "eth0"
-#define TIMEOUT_PERIOD 100
-#define INSERT_TIMEOUT_MS 500
-#define INSERT_RETRIES 50
-#define REMOVE_TIMEOUT_MS 500
-#define REMOVE_RETRIES 50
-#define SEARCH_TIMEOUT_MS 500
-#define SEARCH_RETRIES 50
-
-//message types
-//make sure this matches msg_types global var
-enum
-{
- INSERT_CMD,
- INSERT_RES,
- REMOVE_CMD,
- REMOVE_RES,
- SEARCH_CMD,
- SEARCH_RES,
- WHO_IS_LEADER_CMD,
- WHO_IS_LEADER_RES,
- JOIN_REQ,
- JOIN_RES,
- LEAVE_REQ,
- LEAVE_RES,
- DHT_UPDATE_CMD,
- DHT_UPDATE_RES,
- ELECT_LEADER_CMD,
- ELECT_LEADER_RES,
- CONGRATS_CMD,
- REBUILD_REQ,
- REBUILD_CMD,
- FILL_DHT_CMD,
- FILL_DHT_RES,
- RESUME_NORMAL_CMD,
- RESUME_NORMAL_RES,
- NUM_MSG_TYPES
-};
-
-//states
-//make sure this matches state_names, timeout_vals, and retry_vals global vars
-enum
-{
- INIT1_STATE,
- INIT2_STATE,
- NORMAL_STATE,
- LEAD_NORMAL1_STATE,
- LEAD_NORMAL2_STATE,
- ELECT1_STATE,
- ELECT2_STATE,
- REBUILD0_STATE,
- REBUILD1_STATE,
- REBUILD2_STATE,
- REBUILD3_STATE,
- REBUILD4_STATE,
- REBUILD5_STATE,
- LEAD_REBUILD1_STATE,
- LEAD_REBUILD2_STATE,
- LEAD_REBUILD3_STATE,
- LEAD_REBUILD4_STATE,
- EXIT1_STATE,
- EXIT2_STATE,
- NUM_STATES
-};
-
-//status codes
-enum
-{
- OPERATION_OK,
- KEY_NOT_FOUND,
- NOT_KEY_OWNER,
- NOT_LEADER,
- INTERNAL_ERROR
-};
-
-struct hostData {
- unsigned int ipAddr;
- unsigned int maxKeyCapacity;
-};
-
-/*******************************************************************************
-* Local Function Prototypes
-*******************************************************************************/
-
-int msgSizeOk(unsigned char *msg, unsigned int size);
-unsigned short read2(unsigned char *msg);
-unsigned int read4(unsigned char *msg);
-void write2(unsigned char *ptr, unsigned short tmp);
-void write4(unsigned char *ptr, unsigned int tmp);
-unsigned int getMyIpAddr(const char *interfaceStr);
-int udpSend(unsigned char *msg, unsigned int size, unsigned int destIp);
-int udpSendAll(unsigned char *msg, unsigned int size);
-unsigned int hash(unsigned int x);
-unsigned int getKeyOwner(unsigned int key);
-void setState(unsigned int newState);
-void makeAssignments();
-int addHost(struct hostData newHost);
-int removeHost(unsigned int ipAddr);
-void removeUnresponsiveHosts();
-int checkReplied(unsigned int ipAddr);
-int allReplied();
-void writeHostList();
-void dhtLog(const char *format, ...);
-void *fillTask();
-void *udpListen();
-
-/*******************************************************************************
-* Global Variables
-*******************************************************************************/
-
-//make sure this matches enumeration above
-const char *msg_types[NUM_MSG_TYPES] =
-{
- "INSERT_CMD",
- "INSERT_RES",
- "REMOVE_CMD",
- "REMOVE_RES",
- "SEARCH_CMD",
- "SEARCH_RES",
- "WHO_IS_LEADER_CMD",
- "WHO_IS_LEADER_RES",
- "JOIN_REQ",
- "JOIN_RES",
- "LEAVE_REQ",
- "LEAVE_RES",
- "DHT_UPDATE_CMD",
- "DHT_UPDATE_RES",
- "ELECT_LEADER_CMD",
- "ELECT_LEADER_RES",
- "CONGRATS_CMD",
- "REBUILD_REQ",
- "REBUILD_CMD",
- "FILL_DHT_CMD",
- "FILL_DHT_RES",
- "RESUME_NORMAL_CMD",
- "RESUME_NORMAL_RES"
-};
-
-const char *state_names[NUM_STATES] =
-{
- "INIT1_STATE",
- "INIT2_STATE",
- "NORMAL_STATE",
- "LEAD_NORMAL1_STATE",
- "LEAD_NORMAL2_STATE",
- "ELECT1_STATE",
- "ELECT2_STATE",
- "REBUILD0_STATE",
- "REBUILD1_STATE",
- "REBUILD2_STATE",
- "REBUILD3_STATE",
- "REBUILD4_STATE",
- "REBUILD5_STATE",
- "LEAD_REBUILD1_STATE",
- "LEAD_REBUILD2_STATE",
- "LEAD_REBUILD3_STATE",
- "LEAD_REBUILD4_STATE",
- "EXIT1_STATE",
- "EXIT2_STATE",
-};
-
-//note: { 0, 0 } means no timeout
-struct timeval timeout_vals[NUM_STATES] ={
- { 0, 500000 }, //INIT1_STATE
- { 0, 500000 }, //INIT2_STATE
- { 0, 0 }, //NORMAL_STATE
- { 0, 0 }, //LEAD_NORMAL1_STATE
- { 3, 0 }, //LEAD_NORMAL2_STATE
- { 1, 0 }, //ELECT1_STATE
- { 1, 0 }, //ELECT2_STATE
- { 0, 500000 }, //REBUILD0_STATE
- { 0, 500000 }, //REBUILD1_STATE
- { 10, 0 }, //REBUILD2_STATE
- { 10, 0 }, //REBUILD3_STATE
- { 10, 0 }, //REBUILD4_STATE
- { 1, 0 }, //REBUILD5_STATE
- { 1, 0 }, //LEAD_REBUILD1_STATE
- { 1, 0 }, //LEAD_REBUILD2_STATE
- { 10, 0 }, //LEAD_REBUILD3_STATE
- { 10, 0 }, //LEAD_REBUILD4_STATE
- { 0, 500000 }, //EXIT1_STATE
- { 0, 0 } //EXIT2_STATE
-};
-
-int retry_vals[NUM_STATES] =
-{
- 100, //INIT1_STATE
- 10, //INIT2_STATE
- 0, //NORMAL_STATE
- 0, //LEAD_NORMAL1_STATE
- 0, //LEAD_NORMAL2_STATE
- 10, //ELECT1_STATE
- 10, //ELECT2_STATE
- 10, //REBUILD0_STATE
- 10, //REBUILD1_STATE
- 0, //REBUILD2_STATE
- 0, //REBUILD3_STATE
- 0, //REBUILD4_STATE
- 10, //REBUILD5_STATE
- 10, //LEAD_REBUILD1_STATE
- 10, //LEAD_REBUILD2_STATE
- 10, //LEAD_REBUILD3_STATE
- 10, //LEAD_REBUILD4_STATE
- 10, //EXIT1_STATE
- 0 //EXIT2_STATE
-};
-
-FILE *logfile;
-struct hostData myHostData;
-pthread_t threadUdpListen;
-pthread_t threadFillTask;
-//status of fillTask: 0 = ready to run, 1 = running, 2 = completed, 3 = error
-int fillStatus;
-struct pollfd udpPollSock;
-unsigned int state;
-unsigned int seed;
-unsigned int leader;
-unsigned int electionOriginator;
-unsigned int electionParent;
-unsigned int hostArraySize = 0;
-struct hostData *hostArray = NULL;
-unsigned int numBlocks = 0;
-unsigned short *blockOwnerArray = NULL;
-unsigned char *hostReplied = NULL;
-pthread_mutex_t stateMutex;
-pthread_cond_t stateCond;
-chashtable_t *myHashTable;
-unsigned int numHosts;
-struct timeval timer;
-int timerSet;
-int timeoutCntr;
-
-/*******************************************************************************
-* Interface Function Definitions
-*******************************************************************************/
-
-void dhtInit(unsigned int seedIpAddr, unsigned int maxKeyCapacity) {
- struct in_addr tmpAddr;
- char filename[23] = "dht-";
- struct sockaddr_in myAddr;
- struct sockaddr_in seedAddr;
- socklen_t socklen = sizeof(struct sockaddr_in);
- char initMsg;
-
- tmpAddr.s_addr = htonl(getMyIpAddr(DEFAULT_INTERFACE));
- strcat(filename, inet_ntoa(tmpAddr));
- strcat(filename, ".log");
- printf("log file: %s\n", filename);
-
- logfile = fopen(filename, "w");
- dhtLog("dhtInit(): inializing...\n");
-
- myHostData.ipAddr = getMyIpAddr(DEFAULT_INTERFACE);
- myHostData.maxKeyCapacity = maxKeyCapacity;
-
- seed = seedIpAddr;
- leader = 0;
- electionOriginator = 0;
- electionParent = 0;
- hostArraySize = INIT_HOST_ALLOC;
- hostArray = calloc(hostArraySize, sizeof(struct hostData));
- hostReplied = calloc(hostArraySize, sizeof(unsigned char));
- hostArray[0] = myHostData;
- numHosts = 1;
- numBlocks = INIT_NUM_BLOCKS;
- blockOwnerArray = calloc(numBlocks, sizeof(unsigned short));
- pthread_mutex_init(&stateMutex, NULL);
- pthread_cond_init(&stateCond, NULL);
- myHashTable = chashCreate(HASH_SIZE, LOADFACTOR);
-
- udpPollSock.fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
- if (udpPollSock.fd < 0)
- perror("dhtInit():socket()");
-
- udpPollSock.events = POLLIN;
-
- bzero(&myAddr, socklen);
- myAddr.sin_family = AF_INET;
- myAddr.sin_addr.s_addr = htonl(INADDR_ANY);
- myAddr.sin_port = htons(UDP_PORT);
-
- if (bind(udpPollSock.fd, (struct sockaddr *)&myAddr, socklen) < 0)
- perror("dhtInit():bind()");
-
- if (seed == 0) {
- dhtLog("I am the leader\n");
- leader = myHostData.ipAddr;
- setState(LEAD_NORMAL1_STATE);
- } else
- {
- initMsg = WHO_IS_LEADER_CMD;
- udpSend(&initMsg, 1, seed);
- setState(INIT1_STATE);
- }
-
- if (pthread_create(&threadUdpListen, NULL, udpListen, NULL) != 0)
- dhtLog("dhtInit() - ERROR creating threadUdpListen\n");
-
- return;
-}
-
-void dhtExit() { //TODO: do this gracefully, wait for response from leader, etc.
- char msg;
-
- msg = LEAVE_REQ;
- udpSend(&msg, 1, leader);
- dhtLog("dhtExit(): cleaning up...\n");
- pthread_cancel(threadUdpListen);
- close(udpPollSock.fd);
- free(hostArray);
- free(hostReplied);
- free(blockOwnerArray);
- fclose(logfile);
-
- return;
-}
-
-int dhtInsert(unsigned int key, unsigned int val) {
- struct sockaddr_in toAddr;
- struct sockaddr_in fromAddr;
- socklen_t socklen = sizeof(struct sockaddr_in);
- struct pollfd pollsock;
- char inBuffer[2];
- char outBuffer[9];
- ssize_t bytesRcvd;
- int i;
- int retval;
- int status = -1;
-
- bzero((char *)&toAddr, socklen);
- toAddr.sin_family = AF_INET;
- toAddr.sin_port = htons(UDP_PORT);
-
- while (status != OPERATION_OK) {
- pthread_mutex_lock(&stateMutex);
- while (!(state == NORMAL_STATE || state == LEAD_NORMAL1_STATE
- || state == LEAD_NORMAL2_STATE || state == REBUILD4_STATE
- || state == LEAD_REBUILD3_STATE))
- pthread_cond_wait(&stateCond, &stateMutex);
- toAddr.sin_addr.s_addr = htonl(getKeyOwner(key));
- pthread_mutex_unlock(&stateMutex);
-
- if ((pollsock.fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
- perror("dhtInsert():socket()");
- return -1;
- }
- pollsock.events = POLLIN;
-
- outBuffer[0] = INSERT_CMD;
- write4(&outBuffer[1], key);
- write4(&outBuffer[5], val);
-
- for (i = 0; i < INSERT_RETRIES; i++) {
- if (sendto(pollsock.fd, outBuffer, 9, 0, (struct sockaddr *)&toAddr,
- socklen) < 0) {
- perror("dhtInsert():sendto()");
- break;
- }
- retval = poll(&pollsock, 1, INSERT_TIMEOUT_MS);
- if (retval < 0) {
- perror("dhtInsert():poll()");
- break;
- }
- if (retval > 0) {
- bytesRcvd = recvfrom(pollsock.fd, inBuffer, 2, 0,
- (struct sockaddr *)&fromAddr, &socklen);
- if (fromAddr.sin_addr.s_addr == toAddr.sin_addr.s_addr
- && fromAddr.sin_port == toAddr.sin_port
- && bytesRcvd == 2 && inBuffer[0] == INSERT_RES) {
- status = inBuffer[1]; //status from remote host
- break;
- }
- }
- }
- if (status != OPERATION_OK) {
- pthread_mutex_lock(&stateMutex);
- setState(REBUILD0_STATE);
- outBuffer[0] = REBUILD_REQ;
- udpSend(outBuffer, 1, leader);
- pthread_mutex_unlock(&stateMutex);
- }
- }
-
- close(pollsock.fd);
-
- return status;
-}
-
-int dhtInsertMult(unsigned int numKeys, unsigned int *keys, unsigned int *vals) {
- int status;
- int i;
-
- status = 0;
- for (i = 0; i < numKeys; i++) {
- if (dhtInsert(keys[i], vals[i]) != 0)
- status = -1;
- }
- return status;
-}
-
-int dhtRemove(unsigned int key) {
- struct sockaddr_in toAddr;
- struct sockaddr_in fromAddr;
- socklen_t socklen = sizeof(struct sockaddr_in);
- struct pollfd pollsock;
- char inBuffer[2];
- char outBuffer[5];
- ssize_t bytesRcvd;
- int i;
- int retval;
- int status = -1;
-
- bzero((char *)&toAddr, socklen);
- toAddr.sin_family = AF_INET;
- toAddr.sin_port = htons(UDP_PORT);
-
- while (!(status == OPERATION_OK || status == KEY_NOT_FOUND)) {
- pthread_mutex_lock(&stateMutex);
- while (!(state == NORMAL_STATE || state == LEAD_NORMAL1_STATE
- || state == LEAD_NORMAL2_STATE))
- pthread_cond_wait(&stateCond, &stateMutex);
- toAddr.sin_addr.s_addr = htonl(getKeyOwner(key));
- pthread_mutex_unlock(&stateMutex);
-
- if ((pollsock.fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
- perror("dhtRemove():socket()");
- return -1;
- }
- pollsock.events = POLLIN;
-
- outBuffer[0] = REMOVE_CMD;
- write4(&outBuffer[1], key);
-
- for (i = 0; i < REMOVE_RETRIES; i++) {
- if (sendto(pollsock.fd, outBuffer, 5, 0, (struct sockaddr *)&toAddr,
- socklen) < 0) {
- perror("dhtRemove():sendto()");
- break;
- }
- retval = poll(&pollsock, 1, REMOVE_TIMEOUT_MS);
- if (retval < 0) {
- perror("dhtRemove():poll()");
- break;
- }
- if (retval > 0) {
- bytesRcvd = recvfrom(pollsock.fd, inBuffer, 2, 0,
- (struct sockaddr *)&fromAddr, &socklen);
- if (fromAddr.sin_addr.s_addr == toAddr.sin_addr.s_addr
- && fromAddr.sin_port == toAddr.sin_port
- && bytesRcvd == 2 && inBuffer[0] == REMOVE_RES) {
- status = inBuffer[1]; //status from remote host
- break;
- }
- }
- }
- if (!(status == OPERATION_OK || status == KEY_NOT_FOUND)) {
- pthread_mutex_lock(&stateMutex);
- setState(REBUILD0_STATE);
- outBuffer[0] = REBUILD_REQ;
- udpSend(outBuffer, 1, leader);
- pthread_mutex_unlock(&stateMutex);
- }
- }
-
- close(pollsock.fd);
-
- return status;
-}
-
-int dhtRemoveMult(unsigned int numKeys, unsigned int *keys) {
- int status;
- int i;
-
- status = 0;
- for (i = 0; i < numKeys; i++) {
- if (dhtRemove(keys[i]) != 0)
- status = -1;
- }
- return status;
-}
-
-int dhtSearch(unsigned int key, unsigned int *val) {
- struct sockaddr_in toAddr;
- struct sockaddr_in fromAddr;
- socklen_t socklen = sizeof(struct sockaddr_in);
- struct pollfd pollsock;
- char inBuffer[6];
- char outBuffer[5];
- ssize_t bytesRcvd;
- int i;
- int retval;
- int status = -1;
-
- bzero((char *)&toAddr, socklen);
- toAddr.sin_family = AF_INET;
- toAddr.sin_port = htons(UDP_PORT);
-
- while (!(status == OPERATION_OK || status == KEY_NOT_FOUND)) {
- pthread_mutex_lock(&stateMutex);
- while (numBlocks == 0)
- pthread_cond_wait(&stateCond, &stateMutex);
- toAddr.sin_addr.s_addr = htonl(getKeyOwner(key));
- pthread_mutex_unlock(&stateMutex);
-
- if ((pollsock.fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
- perror("dhtSearch():socket()");
- return -1;
- }
- pollsock.events = POLLIN;
-
- outBuffer[0] = SEARCH_CMD;
- write4(&outBuffer[1], key);
-
- for (i = 0; i < SEARCH_RETRIES; i++) {
- if (sendto(pollsock.fd, outBuffer, 5, 0, (struct sockaddr *)&toAddr,
- socklen) < 0) {
- perror("dhtSearch():sendto()");
- break;
- }
- retval = poll(&pollsock, 1, SEARCH_TIMEOUT_MS);
- if (retval < 0) {
- perror("dhtSearch():poll()");
- break;
- }
- if (retval > 0) {
- bytesRcvd = recvfrom(pollsock.fd, inBuffer, 6, 0,
- (struct sockaddr *)&fromAddr, &socklen);
- if (fromAddr.sin_addr.s_addr == toAddr.sin_addr.s_addr
- && fromAddr.sin_port == toAddr.sin_port
- && bytesRcvd == 6 && inBuffer[0] == SEARCH_RES) {
- status = inBuffer[1]; //status from remote host
- *val = read4(&inBuffer[2]);
- break;
- }
- }
- }
- if (!(status == OPERATION_OK || status == KEY_NOT_FOUND)) {
- pthread_mutex_lock(&stateMutex);
- setState(REBUILD0_STATE);
- outBuffer[0] = REBUILD_REQ;
- udpSend(outBuffer, 1, leader);
- pthread_mutex_unlock(&stateMutex);
- }
- }
-
- close(pollsock.fd);
-
- return status;
-}
-
-int dhtSearchMult(unsigned int numKeys, unsigned int *keys, unsigned int *vals) {
- int i;
- int status = 0;
- for (i = 0; i < numKeys; i++) {
- if (dhtSearch(keys[i], &vals[i]) != 0)
- status = -1;
- }
- return status;
-}
-
-/*******************************************************************************
-* Local Function Definitions
-*******************************************************************************/
-
-int msgSizeOk(unsigned char *msg, unsigned int size) {
- unsigned short tmpNumHosts;
- unsigned short tmpNumBlocks;
-
- if (size < 1)
- return 1;
-
- switch (msg[0]) {
- case WHO_IS_LEADER_CMD:
- case LEAVE_REQ:
- case LEAVE_RES:
- case DHT_UPDATE_RES:
- case REBUILD_REQ:
- case REBUILD_CMD:
- case FILL_DHT_CMD:
- case FILL_DHT_RES:
- case RESUME_NORMAL_CMD:
- case RESUME_NORMAL_RES:
- return (size == 1);
-
- case INSERT_RES:
- case REMOVE_RES:
- case JOIN_RES:
- return (size == 2);
-
- case REMOVE_CMD:
- case SEARCH_CMD:
- case WHO_IS_LEADER_RES:
- case JOIN_REQ:
- case ELECT_LEADER_CMD:
- return (size == 5);
-
- case SEARCH_RES:
- return (size == 6);
-
- case INSERT_CMD:
- return (size == 9);
-
- case DHT_UPDATE_CMD:
- if (size < 5)
- return 1;
- tmpNumHosts = read2(&msg[1]);
- tmpNumBlocks = read2(&msg[3]);
- return (size == (5+sizeof(struct hostData)*tmpNumHosts+2*tmpNumBlocks));
-
- case ELECT_LEADER_RES:
- if (size < 2)
- return 1;
- if (msg[1] == 0xFF)
- return (size == 2);
- if (size < 4)
- return 1;
- tmpNumHosts = read2(&msg[2]);
- return (size == (4 + sizeof(struct hostData) * tmpNumHosts));
-
- case CONGRATS_CMD:
- if (size < 3)
- return 1;
- tmpNumHosts = read2(&msg[1]);
- return (size == (3 + sizeof(struct hostData) * tmpNumHosts));
-
- default:
- return 1;
- }
-}
-
-unsigned short read2(unsigned char *ptr) {
- unsigned short tmp = (ptr[1] << 8) | ptr[0];
- return tmp;
-}
-
-unsigned int read4(unsigned char *ptr) {
- unsigned int tmp = (ptr[3] << 24) | (ptr[2] << 16) | (ptr[1] << 8) | ptr[0];
- return tmp;
-}
-
-void write2(unsigned char *ptr, unsigned short tmp) {
- ptr[1] = (tmp >> 8) & 0xFF;
- ptr[0] = tmp & 0xFF;
- return;
-}
-
-void write4(unsigned char *ptr, unsigned int tmp) {
- ptr[3] = (tmp >> 24) & 0xFF;
- ptr[2] = (tmp >> 16) & 0xFF;
- ptr[1] = (tmp >> 8) & 0xFF;
- ptr[0] = tmp & 0xFF;
- return;
-}
-
-unsigned int getMyIpAddr(const char *interfaceStr) {
- int sock;
- struct ifreq interfaceInfo;
- struct sockaddr_in *myAddr = (struct sockaddr_in *)&interfaceInfo.ifr_addr;
-
- memset(&interfaceInfo, 0, sizeof(struct ifreq));
-
- if((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
- perror("getMyIpAddr():socket()");
- return 1;
- }
-
- strcpy(interfaceInfo.ifr_name, interfaceStr);
- myAddr->sin_family = AF_INET;
-
- if(ioctl(sock, SIOCGIFADDR, &interfaceInfo) != 0) {
- perror("getMyIpAddr():ioctl()");
- return 1;
- }
-
- return ntohl(myAddr->sin_addr.s_addr);
-}
-
-int udpSend(unsigned char *msg, unsigned int size, unsigned int destIp) {
- struct sockaddr_in peerAddr;
- socklen_t socklen = sizeof(struct sockaddr_in);
-
- bzero(&peerAddr, socklen);
- peerAddr.sin_family = AF_INET;
- peerAddr.sin_addr.s_addr = htonl(destIp);
- peerAddr.sin_port = htons(UDP_PORT);
-
- if (size >= 1) {
- if (msg[0] < NUM_MSG_TYPES)
- dhtLog("udpSend(): sending %s to %s, %d bytes\n", msg_types[msg[0]],
- inet_ntoa(peerAddr.sin_addr), size);
- else
- dhtLog("udpSend(): sending unknown message to %s, %d bytes\n",
- inet_ntoa(peerAddr.sin_addr), size);
- }
-
- if (sendto(udpPollSock.fd, (void *)msg, size, 0, (struct sockaddr *)&peerAddr,
- socklen) < 0) {
- perror("udpSend():sendto()");
- return -1;
- }
-
- return 0;
-}
-
-int udpSendAll(unsigned char *msg, unsigned int size) {
- int i;
- int status = 0;
- for (i = 0; i < numHosts; i++) {
- if ((hostReplied[i] == 0) && (hostArray[i].ipAddr != myHostData.ipAddr)) {
- if (udpSend(msg, size, hostArray[i].ipAddr) != 0)
- status = -1;
- }
- }
- return status;
-}
-
-//note: make sure this is only executed in a valid state, where numBlocks != 0
-unsigned int hash(unsigned int x) {
- return (x % numBlocks);
-}
-
-//note: make sure this is only executed in a valid state, where these arrays
-// are allocated and the index mappings are consistent
-unsigned int getKeyOwner(unsigned int key) {
- return hostArray[blockOwnerArray[hash(key)]].ipAddr;
-}
-
-//sets state and timer, if applicable
-void setState(unsigned int newState) {
- struct timeval now;
- int i;
-
- gettimeofday(&now, NULL);
-
- if (newState >= NUM_STATES) {
- dhtLog("setState(): ERROR: invalid state %d\n", newState);
- } else
- {
- if (timeout_vals[newState].tv_sec == 0
- && timeout_vals[newState].tv_usec == 0) { //no timer
- timerSet = 0;
- } else
- {
- timeradd(&now, &timeout_vals[newState], &timer);
- timerSet = 1;
- }
- timeoutCntr = 0;
- state = newState;
- //TODO: only do this for states that require it
- for (i = 0; i < numHosts; i++)
- hostReplied[i] = 0;
-
- dhtLog("setState(): state set to %s\n", state_names[state]);
- }
-
- return;
-}
-
-//TODO: improve these simple and inefficient functions
-int checkReplied(unsigned int ipAddr) {
- int i;
-
- i = findHost(ipAddr);
-
- if (i == -1)
- return -1;
-
- hostReplied[i] = 1;
-
- return 0;
-}
-
-int allReplied() {
- int i;
-
- for (i = 0; i < numHosts; i++)
- if ((hostReplied[i] == 0) && (hostArray[i].ipAddr != myHostData.ipAddr))
- return 0;
-
- return 1;
-}
-
-int findHost(unsigned int ipAddr) {
- int i;
-
- for (i = 0; i < numHosts; i++)
- if (hostArray[i].ipAddr == ipAddr)
- return i; //found, return index
-
- return -1; //not found
-}
-
-int removeHost(unsigned int ipAddr) {
- int i, j;
-
- i = findHost(ipAddr);
-
- if (i == -1)
- return -1;
-
- for (j = 0; j < numBlocks; j++) {
- if (blockOwnerArray[j] == i)
- blockOwnerArray[j] = 0; //TODO: is this what I want to have happen?
- else if (blockOwnerArray[j] > i)
- blockOwnerArray[j]--;
- }
-
- for (; i < numHosts - 1; i++) {
- hostArray[i] = hostArray[i+1];
- hostReplied[i] = hostReplied[i+1];
- }
- numHosts--;
-
- return 0;
-}
-
-void removeUnresponsiveHosts() {
- int i;
-
- for (i = 0; i < numHosts; i++) {
- if (!hostReplied[i] && hostArray[i].ipAddr != myHostData.ipAddr)
- removeHost(hostArray[i].ipAddr);
- }
-}
-
-int addHost(struct hostData newHost) {
- struct hostData *newHostArray;
- unsigned char *newHostReplied;
- int i;
- int j;
-
- for (i = 0; i < numHosts; i++) {
- if (hostArray[i].ipAddr == newHost.ipAddr) {
- hostArray[i] = newHost;
- hostReplied[i] = 0;
- return 0;
- } else if (hostArray[i].ipAddr > newHost.ipAddr) {
- if (numHosts == hostArraySize) {
- newHostArray = calloc(2 * hostArraySize, sizeof(struct hostData));
- newHostReplied = calloc(2 * hostArraySize, sizeof(unsigned char));
- memcpy(newHostArray, hostArray, (i * sizeof(struct hostData)));
- memcpy(newHostReplied, hostReplied, (i * sizeof(unsigned char)));
- newHostArray[i] = newHost;
- newHostReplied[i] = 0;
- memcpy(&newHostArray[i+1], &hostArray[i], ((numHosts - i) *
- sizeof(struct hostData)));
- memcpy(&newHostReplied[i+1], &hostReplied[i], ((numHosts - i) *
- sizeof(unsigned char)));
- free(hostArray);
- free(hostReplied);
- hostArray = newHostArray;
- hostReplied = newHostReplied;
- hostArraySize = 2 * hostArraySize;
- } else
- {
- for (j = numHosts; j > i; j--) {
- hostArray[j] = hostArray[j-1];
- hostReplied[j] = hostReplied[j-1];
- }
- hostArray[i] = newHost;
- hostReplied[i] = 0;
- }
- for(j = 0; j < numBlocks; j++) {
- if (blockOwnerArray[j] >= i)
- blockOwnerArray[j]++;
- }
- numHosts++;
- return 1;
- }
- }
-
- //nothing greater, add to end
- if (numHosts == hostArraySize) {
- newHostArray = calloc(2 * hostArraySize, sizeof(struct hostData));
- newHostReplied = calloc(2 * hostArraySize, sizeof(unsigned char));
- memcpy(newHostArray, hostArray, (numHosts * sizeof(struct hostData)));
- memcpy(newHostReplied, hostReplied, (numHosts * sizeof(unsigned char)));
- free(hostArray);
- free(hostReplied);
- hostArray = newHostArray;
- hostReplied = newHostReplied;
- hostArraySize = 2 * hostArraySize;
- }
-
- hostArray[numHosts] = newHost;
- hostReplied[numHosts] = 0;
- numHosts++;
- return 1;
-}
-
-void makeAssignments() {
- int i;
-
- if (numBlocks < numHosts) {
- free(blockOwnerArray);
- while (numBlocks < numHosts)
- numBlocks *= 2;
- blockOwnerArray = calloc(numBlocks, sizeof(unsigned short));
- }
-
- for (i = 0; i < numBlocks; i++)
- blockOwnerArray[i] = i % numHosts;
-
- return;
-}
-
-void writeHostList() {
- int i;
- struct in_addr tmpAddr;
-
- fprintf(logfile, "numHosts = %d\n", numHosts);
- for (i = 0; i < numHosts; i++) {
- tmpAddr.s_addr = htonl(hostArray[i].ipAddr);
- fprintf(logfile, "%d) %s, %d\n", i, inet_ntoa(tmpAddr),
- hostArray[i].maxKeyCapacity);
- }
- return;
-}
-
-void dhtLog(const char *format, ...) {
- va_list args;
-// struct timeval now;
-
-// if (gettimeofday(&now, NULL) < 0)
-// { perror("dhtLog():gettimeofday()"); }
- va_start(args, format);
-// if (fprintf(logfile, "%d.%06d:", now.tv_sec, now.tv_usec) < 0)
-// { perror("dhtLog():fprintf()"); }
- if (vfprintf(logfile, format, args) < 0) {
- perror("dhtLog():vfprintf()");
- }
- if (fflush(logfile) == EOF) {
- perror("dhtLog():fflush()");
- }
- va_end(args);
-
- return;
-}
-
-void *fillTask() {
- unsigned int *vals;
- unsigned int *keys;
- unsigned int numKeys;
- int i;
-
- vals = mhashGetKeys(&numKeys); //note: key of mhash is val of dht
- keys = calloc(numKeys, sizeof(unsigned int));
-
- for (i = 0; i < numKeys; i++)
- keys[i] = myHostData.ipAddr;
-
- if (dhtInsertMult(numKeys, keys, vals) == 0)
- fillStatus = 2;
- else
- fillStatus = 3;
-
- pthread_exit(NULL);
-}
-
-void *udpListen() {
- ssize_t bytesRcvd;
- struct sockaddr_in peerAddr;
- unsigned int peerIp;
- socklen_t socklen = sizeof(struct sockaddr_in);
- unsigned char inBuffer[MAX_MSG_SIZE];
- unsigned char outBuffer[MAX_MSG_SIZE];
- int pollret;
- struct timeval now;
- struct in_addr tmpAddr;
- struct hostData tmpHost;
- unsigned int tmpKey;
- unsigned int tmpVal;
- struct hostData *hostDataPtr;
- unsigned short *uShortPtr;
- unsigned int tmpUInt;
- unsigned int tmpUShort;
- int i;
- unsigned int oldState;
-
- dhtLog("udpListen(): linstening on port %d...\n", UDP_PORT);
-
- while (1) {
- pollret = poll(&udpPollSock, 1, TIMEOUT_PERIOD);
- pthread_mutex_lock(&stateMutex);
- oldState = state;
- if (pollret < 0) {
- perror("udpListen():poll()");
- } else if (pollret > 0) {
- bytesRcvd = recvfrom(udpPollSock.fd, inBuffer, MAX_MSG_SIZE, 0,
- (struct sockaddr *)&peerAddr, &socklen);
- if (bytesRcvd < 1) {
- dhtLog("udpListen(): ERROR: bytesRcvd = %d\n", bytesRcvd);
- } else if (inBuffer[0] >= NUM_MSG_TYPES) {
- dhtLog("udpListen(): ERROR: unknown msg type = %d\n", inBuffer[0]);
- } else if (!msgSizeOk(inBuffer, bytesRcvd)) {
- dhtLog("udpListen(): ERROR: msg size not ok: type = %s\n, size = %d\n",
- msg_types[inBuffer[0]], bytesRcvd);
- } else if (state == EXIT2_STATE) {
- //do nothing
- } else if (state == INIT1_STATE) { //after initialization with seed, do not proceed until seed replies
- dhtLog("udpListen(): received %s from %s, %d bytes\n",
- msg_types[inBuffer[0]], inet_ntoa(peerAddr.sin_addr), bytesRcvd);
- for (i = 0; i < bytesRcvd; i++)
- dhtLog(" %x", inBuffer[i]);
- dhtLog("\n");
- peerIp = ntohl(peerAddr.sin_addr.s_addr);
- if (peerIp == seed && inBuffer[0] == WHO_IS_LEADER_RES) {
- tmpHost.ipAddr = peerIp;
- tmpHost.maxKeyCapacity = 0;
- addHost(tmpHost);
- writeHostList();
- leader = read4(&inBuffer[1]);
- tmpAddr.s_addr = htonl(leader);
- dhtLog("leader = %s\n", inet_ntoa(tmpAddr));
- if (leader != 0) {
- setState(INIT2_STATE);
- outBuffer[0] = JOIN_REQ;
- write4(&outBuffer[1], myHostData.maxKeyCapacity);
- udpSend(outBuffer, 5, leader);
- } else
- {
- electionOriginator = myHostData.ipAddr;
- setState(ELECT1_STATE);
- outBuffer[0] = ELECT_LEADER_CMD;
- write4(&outBuffer[1], myHostData.ipAddr); //originator = me
- udpSendAll(outBuffer, 5);
- }
- }
- } else
- {
- dhtLog("udpListen(): received %s from %s, %d bytes\n",
- msg_types[inBuffer[0]], inet_ntoa(peerAddr.sin_addr), bytesRcvd);
- for (i = 0; i < bytesRcvd; i++)
- dhtLog(" %x", inBuffer[i]);
- dhtLog("\n");
- peerIp = ntohl(peerAddr.sin_addr.s_addr);
- switch (inBuffer[0]) {
- case INSERT_CMD:
- if (state == NORMAL_STATE || state == LEAD_NORMAL1_STATE
- || state == LEAD_NORMAL2_STATE || state == REBUILD4_STATE
- || state == REBUILD5_STATE || state == LEAD_REBUILD3_STATE) {
- tmpKey = read4(&inBuffer[1]);
- tmpVal = read4(&inBuffer[5]);
- outBuffer[0] = INSERT_RES;
- if (getKeyOwner(tmpKey) == myHostData.ipAddr) {
- if (chashInsert(myHashTable, tmpKey, (void *)tmpVal) == 0)
- outBuffer[1] = OPERATION_OK;
- else
- outBuffer[1] = INTERNAL_ERROR;
- } else
- {
- outBuffer[1] = NOT_KEY_OWNER;
- }
- //reply to client socket
- sendto(udpPollSock.fd, outBuffer, 2, 0,
- (struct sockaddr *)&peerAddr, socklen);
- }
- break;
-
- case REMOVE_CMD:
- if (state == NORMAL_STATE || state == LEAD_NORMAL1_STATE
- || state == LEAD_NORMAL2_STATE) {
- tmpKey = read4(&inBuffer[1]);
- outBuffer[0] = REMOVE_RES;
- if (getKeyOwner(tmpKey) == myHostData.ipAddr) {
- if (chashRemove(myHashTable, tmpKey) == 0)
- outBuffer[1] = OPERATION_OK;
- else
- outBuffer[1] = KEY_NOT_FOUND;
- } else
- {
- outBuffer[1] = NOT_KEY_OWNER;
- }
- //reply to client socket
- sendto(udpPollSock.fd, outBuffer, 2, 0,
- (struct sockaddr *)&peerAddr, socklen);
- }
- break;
-
- case SEARCH_CMD:
- if (state == NORMAL_STATE || state == LEAD_NORMAL1_STATE
- || state == LEAD_NORMAL2_STATE) {
- tmpKey = read4(&inBuffer[1]);
- outBuffer[0] = SEARCH_RES;
- if (getKeyOwner(tmpKey) == myHostData.ipAddr) {
- if ((tmpVal = (unsigned int)chashSearch(myHashTable, tmpKey)) != 0) {
- outBuffer[1] = OPERATION_OK;
- write4(&outBuffer[2], tmpVal);
- } else
- {
- outBuffer[1] = KEY_NOT_FOUND;
- write4(&outBuffer[2], 0);
- }
- } else
- {
- outBuffer[1] = NOT_KEY_OWNER;
- write4(&outBuffer[2], 0);
- }
- //reply to client socket
- sendto(udpPollSock.fd, outBuffer, 6, 0,
- (struct sockaddr *)&peerAddr, socklen);
- }
- break;
-
- case WHO_IS_LEADER_CMD:
- tmpHost.ipAddr = peerIp;
- tmpHost.maxKeyCapacity = 0;
- addHost(tmpHost);
- writeHostList();
- outBuffer[0] = WHO_IS_LEADER_RES;
- //leader == 0 means I don't know who it is
- write4(&outBuffer[1], leader);
- udpSend(outBuffer, 5, peerIp);
- break;
-
- case JOIN_REQ:
- if (state == LEAD_NORMAL1_STATE || state == LEAD_NORMAL2_STATE) {
- tmpHost.ipAddr = peerIp;
- tmpHost.maxKeyCapacity = read4(&inBuffer[1]);
- addHost(tmpHost);
- writeHostList();
- if (state == LEAD_NORMAL1_STATE)
- setState(LEAD_NORMAL2_STATE);
- outBuffer[0] = JOIN_RES;
- outBuffer[1] = 0; //status, success
- udpSend(outBuffer, 2, peerIp);
- } else if (state == LEAD_REBUILD1_STATE) {
- //note: I don't need to addHost().
- checkReplied(peerIp);
- outBuffer[0] = JOIN_RES;
- outBuffer[1] = 0; //status, success
- udpSend(outBuffer, 2, peerIp);
- if (allReplied()) {
- makeAssignments();
- setState(LEAD_REBUILD2_STATE);
- outBuffer[0] = DHT_UPDATE_CMD;
- write2(&outBuffer[1], numHosts);
- write2(&outBuffer[3], numBlocks);
- memcpy(&outBuffer[5], hostArray, numHosts*sizeof(struct hostData));
- memcpy(&outBuffer[5+numHosts*sizeof(struct hostData)],
- blockOwnerArray, numBlocks*2);
- udpSendAll(outBuffer, 5 + sizeof(struct hostData) * numHosts
- + 2 * numBlocks);
- }
- }
- break;
-
- case JOIN_RES:
- if (state == REBUILD1_STATE) {
- setState(REBUILD2_STATE);
- } else if (state == INIT2_STATE) {
- setState(NORMAL_STATE);
- }
- break;
-
- case LEAVE_REQ:
- if (state == LEAD_NORMAL1_STATE || state == LEAD_NORMAL2_STATE) { //TODO: make this graceful, instead of just rebuilding
- removeHost(peerIp);
- if (state != LEAD_NORMAL2_STATE)
- setState(LEAD_NORMAL2_STATE);
- }
- break;
-
- case DHT_UPDATE_CMD:
- if (state == REBUILD2_STATE && peerIp == leader) {
- free(hostArray);
- free(blockOwnerArray);
- numHosts = read2(&inBuffer[1]);
- numBlocks = read2(&inBuffer[3]);
- while (hostArraySize < numHosts)
- hostArraySize *= 2;
- hostArray = calloc(hostArraySize, sizeof(struct hostData));
- blockOwnerArray = calloc(numBlocks, 2);
- memcpy(hostArray, &inBuffer[5], numHosts*sizeof(struct hostData));
- memcpy(blockOwnerArray, &inBuffer[5+numHosts*sizeof(struct hostData)], numBlocks*2);
- writeHostList();
- setState(REBUILD3_STATE);
- outBuffer[0] = DHT_UPDATE_RES;
- udpSend(outBuffer, 1, peerIp);
- }
- break;
-
- case DHT_UPDATE_RES:
- if (state == LEAD_REBUILD2_STATE) {
- checkReplied(peerIp);
- if (allReplied()) {
- setState(LEAD_REBUILD3_STATE);
- outBuffer[0] = FILL_DHT_CMD;
- udpSendAll(outBuffer, 1);
- if (fillStatus != 0)
- dhtLog("udpListen(): ERROR: fillTask already running\n");
- fillStatus = 1;
- if (pthread_create(&threadFillTask, NULL, fillTask, NULL) != 0)
- dhtLog("udpListen(): ERROR creating threadFillTask\n");
- }
- }
- break;
-
- case ELECT_LEADER_CMD:
- tmpUInt = read4(&inBuffer[1]);
- if ((state == ELECT1_STATE || state == ELECT2_STATE)
- && tmpUInt >= electionOriginator) { //already participating in a higher-priority election
- outBuffer[0] = ELECT_LEADER_RES;
- outBuffer[1] = 0xFF;
- udpSend(outBuffer, 2, peerIp);
- } else
- { //join election
- electionOriginator = tmpUInt;
- electionParent = peerIp;
- setState(ELECT1_STATE);
- outBuffer[0] = ELECT_LEADER_CMD;
- write4(&outBuffer[1], electionOriginator);
- //don't bother forwarding the message to originator or parent
- checkReplied(electionOriginator);
- checkReplied(electionParent);
- if (allReplied()) { //in case that is everybody I know of
- setState(ELECT2_STATE);
- outBuffer[0] = ELECT_LEADER_RES;
- outBuffer[1] = 0;
- write2(&outBuffer[2], numHosts);
- memcpy(&outBuffer[4], hostArray, sizeof(struct hostData)
- * numHosts);
- udpSend(outBuffer, 4 + sizeof(struct hostData) * numHosts,
- electionParent);
- } else
- {
- udpSendAll(outBuffer, 5);
- }
- }
- break;
-
- case ELECT_LEADER_RES:
- if (state == ELECT1_STATE) {
- checkReplied(peerIp);
- if (inBuffer[1] != 0xFF) {
- tmpUShort = read2(&inBuffer[2]);
- hostDataPtr = (struct hostData *)&inBuffer[4];
- for (i = 0; i < tmpUShort; i++)
- addHost(hostDataPtr[i]);
- writeHostList();
- }
- if (allReplied()) {
- setState(ELECT2_STATE);
- if (electionOriginator == myHostData.ipAddr) {
- leader = hostArray[0].ipAddr;
- if (leader == myHostData.ipAddr) { //I am the leader
- dhtLog("I am the leader!\n");
- setState(LEAD_REBUILD1_STATE);
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- } else
- { //notify leader
- outBuffer[0] = CONGRATS_CMD;
- write2(&outBuffer[1], numHosts);
- hostDataPtr = (struct hostData *)&outBuffer[3];
- for (i = 0; i < numHosts; i++)
- hostDataPtr[i] = hostArray[i];
- udpSend(outBuffer, 3 + sizeof(struct hostData) * numHosts,
- leader);
- }
- } else
- {
- outBuffer[0] = ELECT_LEADER_RES;
- outBuffer[1] = 0;
- write2(&outBuffer[2], numHosts);
- hostDataPtr = (struct hostData *)&outBuffer[4];
- for (i = 0; i < numHosts; i++)
- hostDataPtr[i] = hostArray[i];
- udpSend(outBuffer, 4 + sizeof(struct hostData) * numHosts,
- electionParent);
- }
- }
- }
- break;
-
- case CONGRATS_CMD:
- if (state == ELECT2_STATE) { //I am the leader
- leader = myHostData.ipAddr;
- dhtLog("I am the leader!\n");
- tmpUShort = read2(&inBuffer[1]);
- hostDataPtr = (struct hostData *)&inBuffer[3];
- for (i = 0; i < tmpUShort; i++)
- addHost(hostDataPtr[i]);
- writeHostList();
- setState(LEAD_REBUILD1_STATE);
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- }
- break;
-
- case REBUILD_REQ:
- if (state == LEAD_NORMAL1_STATE || state == LEAD_NORMAL2_STATE) {
- setState(LEAD_REBUILD1_STATE);
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- }
- break;
-
- case REBUILD_CMD:
- leader = peerIp; //consider this a declaration of authority
- setState(REBUILD1_STATE);
- outBuffer[0] = JOIN_REQ;
- write4(&outBuffer[1], myHostData.maxKeyCapacity);
- udpSend(outBuffer, 5, leader);
- break;
-
- case FILL_DHT_CMD:
- if (state == REBUILD3_STATE && peerIp == leader) {
- setState(REBUILD4_STATE);
- if (fillStatus != 0)
- dhtLog("udpListen(): ERROR: fillTask already running\n");
- fillStatus = 1;
- if (pthread_create(&threadFillTask, NULL, fillTask, NULL) != 0)
- dhtLog("udpListen(): ERROR creating threadFillTask\n");
- }
- break;
-
- case FILL_DHT_RES:
- if (state == LEAD_REBUILD3_STATE) {
- checkReplied(peerIp);
- if (allReplied() && fillStatus == 2) {
- fillStatus = 0;
- setState(LEAD_REBUILD4_STATE);
- outBuffer[0] = RESUME_NORMAL_CMD;
- udpSendAll(outBuffer, 1);
- }
- }
- break;
-
- case RESUME_NORMAL_CMD:
- if (state == REBUILD5_STATE && peerIp == leader) {
- setState(NORMAL_STATE);
- outBuffer[0] = RESUME_NORMAL_RES;
- udpSend(outBuffer, 1, leader);
- }
- break;
-
- case RESUME_NORMAL_RES:
- if (state == LEAD_REBUILD4_STATE) {
- checkReplied(peerIp);
- if (allReplied()) {
- setState(LEAD_NORMAL1_STATE);
- }
- }
- break;
- }
- }
- }
- if (state == REBUILD4_STATE) {
- switch (fillStatus) {
- case 0: dhtLog("udpListen(): ERROR: fillStatus=0 in REBUILD4_STATE\n");
- break;
-
- case 1: //do nothing
- break;
-
- case 2: //done filling the dht, notify leader
- fillStatus = 0;
- setState(REBUILD5_STATE);
- outBuffer[0] = FILL_DHT_RES;
- udpSend(outBuffer, 1, leader);
- break;
-
- case 3: //error encountered -> restart rebuild
- fillStatus = 0;
- setState(REBUILD0_STATE);
- outBuffer[0] = REBUILD_REQ;
- udpSend(outBuffer, 1, leader);
- break;
- }
- }
- if (state == LEAD_REBUILD3_STATE) {
- switch (fillStatus) {
- case 0: dhtLog("udpListen(): ERROR: fillStatus=0 in LEAD_REBUILD3_STATE\n");
- break;
-
- case 1: //do nothing
- break;
-
- case 2: //I'm done, now is everybody else also done?
- if (allReplied()) {
- fillStatus = 0;
- setState(LEAD_REBUILD4_STATE);
- outBuffer[0] = RESUME_NORMAL_CMD;
- udpSendAll(outBuffer, 1);
- }
- break;
-
- case 3: //error encountered -> restart rebuild
- fillStatus = 0;
- setState(LEAD_REBUILD1_STATE);
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- break;
- }
- }
- if (timerSet) {
- gettimeofday(&now, NULL);
- if (timercmp(&now, &timer, >)) {
- if (timeoutCntr < retry_vals[state]) {
- timeoutCntr++;
- timeradd(&now, &timeout_vals[state], &timer);
- dhtLog("udpListen(): retry: %d\n", timeoutCntr);
- switch (state) {
- case INIT1_STATE:
- outBuffer[0] = WHO_IS_LEADER_CMD;
- udpSend(outBuffer, 1, seed);
- break;
-
- case INIT2_STATE:
- outBuffer[0] = JOIN_REQ;
- write4(&outBuffer[1], myHostData.maxKeyCapacity);
- udpSend(outBuffer, 5, leader);
- break;
-
- case ELECT1_STATE:
- outBuffer[0] = ELECT_LEADER_CMD;
- write4(&outBuffer[1], electionOriginator);
- udpSendAll(outBuffer, 5);
- break;
-
- case ELECT2_STATE:
- if (electionOriginator == myHostData.ipAddr) { //retry notify leader
- outBuffer[0] = CONGRATS_CMD;
- write2(&outBuffer[1], numHosts);
- memcpy(&outBuffer[3], hostArray, sizeof(struct hostData)
- * numHosts);
- udpSend(outBuffer, 3 + sizeof(struct hostData) * numHosts,
- leader);
- } else
- {
- outBuffer[0] = ELECT_LEADER_RES;
- outBuffer[1] = 0;
- write2(&outBuffer[2], numHosts);
- memcpy(&outBuffer[4], hostArray, sizeof(struct hostData)
- * numHosts);
- udpSend(outBuffer, 4 + sizeof(struct hostData) * numHosts,
- electionParent);
- }
- break;
-
- case REBUILD0_STATE:
- outBuffer[0] = REBUILD_REQ;
- udpSend(outBuffer, 1, leader);
- break;
-
- case REBUILD1_STATE:
- outBuffer[0] = JOIN_REQ;
- write4(&outBuffer[1], myHostData.maxKeyCapacity);
- udpSend(outBuffer, 5, leader);
- break;
-
- case REBUILD5_STATE:
- outBuffer[0] = FILL_DHT_RES;
- udpSend(outBuffer, 1, leader);
- break;
-
- case LEAD_REBUILD1_STATE:
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- break;
-
- case LEAD_REBUILD2_STATE:
- outBuffer[0] = DHT_UPDATE_CMD;
- write2(&outBuffer[1], numHosts);
- write2(&outBuffer[3], numBlocks);
- memcpy(&outBuffer[5], hostArray, numHosts
- * sizeof(struct hostData));
- memcpy(&outBuffer[5+numHosts*sizeof(struct hostData)],
- blockOwnerArray, numBlocks*2);
- udpSendAll(outBuffer, 5 + sizeof(struct hostData) * numHosts
- + 2 * numBlocks);
- break;
-
- case LEAD_REBUILD3_STATE:
- outBuffer[0] = FILL_DHT_CMD;
- udpSendAll(outBuffer, 1);
- break;
-
- case LEAD_REBUILD4_STATE:
- outBuffer[0] = RESUME_NORMAL_CMD;
- udpSendAll(outBuffer, 1);
- break;
-
- case EXIT1_STATE: //TODO...
- break;
-
- case NORMAL_STATE:
- case LEAD_NORMAL1_STATE:
- case LEAD_NORMAL2_STATE:
- case REBUILD2_STATE:
- case REBUILD3_STATE:
- case REBUILD4_STATE:
- case EXIT2_STATE: //we shouldn't get here
- break;
- }
- } else
- {
- dhtLog("udpListen(): timed out in state %s after %d retries\n",
- state_names[state], timeoutCntr);
- switch (state) {
- case INIT1_STATE:
- setState(EXIT2_STATE);
- break;
-
- case LEAD_NORMAL2_STATE:
- setState(LEAD_REBUILD1_STATE);
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- break;
-
- case ELECT1_STATE:
- dhtLog("removing unresponsive hosts, before:\n");
- writeHostList();
- removeUnresponsiveHosts();
- dhtLog("after\n");
- writeHostList();
- setState(ELECT2_STATE);
- if (electionOriginator == myHostData.ipAddr) {
- leader = hostArray[0].ipAddr;
- if (leader == myHostData.ipAddr) { //I am the leader
- dhtLog("I am the leader!\n");
- setState(LEAD_REBUILD1_STATE);
- outBuffer[0] = REBUILD_CMD;
- udpSendAll(outBuffer, 1);
- } else
- { //notify leader
- outBuffer[0] = CONGRATS_CMD;
- write2(&outBuffer[1], numHosts);
- memcpy(&outBuffer[3], hostArray, sizeof(struct hostData)
- * numHosts);
- udpSend(outBuffer, 3 + sizeof(struct hostData) * numHosts,
- leader);
- }
- } else
- {
- outBuffer[0] = ELECT_LEADER_RES;
- outBuffer[1] = 0;
- write2(&outBuffer[2], numHosts);
- memcpy(&outBuffer[4], hostArray, sizeof(struct hostData)
- * numHosts);
- udpSend(outBuffer, 4 + sizeof(struct hostData) * numHosts,
- electionParent);
- }
- break;
-
- case INIT2_STATE:
- case ELECT2_STATE:
- case REBUILD0_STATE:
- case REBUILD1_STATE:
- case REBUILD2_STATE:
- case REBUILD3_STATE:
- case REBUILD4_STATE:
- case REBUILD5_STATE:
- case LEAD_REBUILD1_STATE:
- case LEAD_REBUILD2_STATE:
- case LEAD_REBUILD3_STATE:
- case LEAD_REBUILD4_STATE:
- //start election
- electionOriginator = myHostData.ipAddr;
- setState(ELECT1_STATE);
- outBuffer[0] = ELECT_LEADER_CMD;
- write4(&outBuffer[1], myHostData.ipAddr); //originator = me
- udpSendAll(outBuffer, 5);
- break;
-
- case EXIT1_STATE:
- setState(EXIT2_STATE);
- break;
-
- case NORMAL_STATE:
- case LEAD_NORMAL1_STATE:
- case EXIT2_STATE: //we shouldn't get here
- break;
- }
- }
- }
- }
- if (state != oldState)
- pthread_cond_broadcast(&stateCond);
- pthread_mutex_unlock(&stateMutex);
- }
-}
-
projects / IRC.git / blobdiff