diff --git a/ikcp.c b/ikcp.c new file mode 100644 index 0000000..33eb18d --- /dev/null +++ b/ikcp.c @@ -0,0 +1,1182 @@ +//===================================================================== +// +// KCP - A Better ARQ Protocol Implementation +// skywind3000 (at) gmail.com, 2010-2011 +// +// Features: +// + Average RTT reduce 30% - 40% vs traditional ARQ like tcp. +// + Maximum RTT reduce three times vs tcp. +// + Lightweight, distributed as a single source file. +// +//===================================================================== +#include "ikcp.h" + +#include +#include +#include +#include + + + +//===================================================================== +// KCP BASIC +//===================================================================== +const IUINT32 IKCP_RTO_NDL = 30; // no delay min rto +const IUINT32 IKCP_RTO_MIN = 100; // normal min rto +const IUINT32 IKCP_RTO_DEF = 200; +const IUINT32 IKCP_RTO_MAX = 60000; +const IUINT32 IKCP_CMD_PUSH = 81; // cmd: push data +const IUINT32 IKCP_CMD_ACK = 82; // cmd: ack +const IUINT32 IKCP_CMD_WASK = 83; // cmd: window probe (ask) +const IUINT32 IKCP_CMD_WINS = 84; // cmd: window size (tell) +const IUINT32 IKCP_ASK_SEND = 1; // need to send IKCP_CMD_WASK +const IUINT32 IKCP_ASK_TELL = 2; // need to send IKCP_CMD_WINS +const IUINT32 IKCP_WND_SND = 32; +const IUINT32 IKCP_WND_RCV = 32; +const IUINT32 IKCP_MTU_DEF = 1400; +const IUINT32 IKCP_ACK_FAST = 3; +const IUINT32 IKCP_INTERVAL = 100; +const IUINT32 IKCP_OVERHEAD = 24; +const IUINT32 IKCP_DEADLINK = 10; +const IUINT32 IKCP_THRESH_INIT = 2; +const IUINT32 IKCP_THRESH_MIN = 2; +const IUINT32 IKCP_PROBE_INIT = 7000; // 7 secs to probe window size +const IUINT32 IKCP_PROBE_LIMIT = 120000; // up to 120 secs to probe window + + +//--------------------------------------------------------------------- +// encode / decode +//--------------------------------------------------------------------- + +/* encode 8 bits unsigned int */ +static inline char *ikcp_encode8u(char *p, unsigned char c) +{ + *(unsigned char*)p++ = c; + return p; +} + +/* decode 8 bits unsigned int */ +static inline const char *ikcp_decode8u(const char *p, unsigned char *c) +{ + *c = *(unsigned char*)p++; + return p; +} + +/* encode 16 bits unsigned int (lsb) */ +static inline char *ikcp_encode16u(char *p, unsigned short w) +{ +#if IWORDS_BIG_ENDIAN + *(unsigned char*)(p + 0) = (w & 255); + *(unsigned char*)(p + 1) = (w >> 8); +#else + *(unsigned short*)(p) = w; +#endif + p += 2; + return p; +} + +/* decode 16 bits unsigned int (lsb) */ +static inline const char *ikcp_decode16u(const char *p, unsigned short *w) +{ +#if IWORDS_BIG_ENDIAN + *w = *(const unsigned char*)(p + 1); + *w = *(const unsigned char*)(p + 0) + (*w << 8); +#else + *w = *(const unsigned short*)p; +#endif + p += 2; + return p; +} + +/* encode 32 bits unsigned int (lsb) */ +static inline char *ikcp_encode32u(char *p, IUINT32 l) +{ +#if IWORDS_BIG_ENDIAN + *(unsigned char*)(p + 0) = (unsigned char)((l >> 0) & 0xff); + *(unsigned char*)(p + 1) = (unsigned char)((l >> 8) & 0xff); + *(unsigned char*)(p + 2) = (unsigned char)((l >> 16) & 0xff); + *(unsigned char*)(p + 3) = (unsigned char)((l >> 24) & 0xff); +#else + *(IUINT32*)p = l; +#endif + p += 4; + return p; +} + +/* decode 32 bits unsigned int (lsb) */ +static inline const char *ikcp_decode32u(const char *p, IUINT32 *l) +{ +#if IWORDS_BIG_ENDIAN + *l = *(const unsigned char*)(p + 3); + *l = *(const unsigned char*)(p + 2) + (*l << 8); + *l = *(const unsigned char*)(p + 1) + (*l << 8); + *l = *(const unsigned char*)(p + 0) + (*l << 8); +#else + *l = *(const IUINT32*)p; +#endif + p += 4; + return p; +} + +static inline IUINT32 _imin_(IUINT32 a, IUINT32 b) { + return a <= b ? a : b; +} + +static inline IUINT32 _imax_(IUINT32 a, IUINT32 b) { + return a >= b ? a : b; +} + +static inline IUINT32 _ibound_(IUINT32 lower, IUINT32 middle, IUINT32 upper) +{ + return _imin_(_imax_(lower, middle), upper); +} + +static inline long _itimediff(IUINT32 later, IUINT32 earlier) +{ + return ((IINT32)(later - earlier)); +} + +//--------------------------------------------------------------------- +// manage segment +//--------------------------------------------------------------------- +typedef struct IKCPSEG IKCPSEG; + +static void* (*ikcp_malloc_hook)(size_t) = NULL; +static void (*ikcp_free_hook)(void *) = NULL; + +// internal malloc +static void* ikcp_malloc(size_t size) { + if (ikcp_malloc_hook) + return ikcp_malloc_hook(size); + return malloc(size); +} + +// internal free +static void ikcp_free(void *ptr) { + if (ikcp_free_hook) { + ikcp_free_hook(ptr); + } else { + free(ptr); + } +} + +// redefine allocator +void ikcp_allocator(void* (*new_malloc)(size_t), void (*new_free)(void*)) +{ + ikcp_malloc_hook = new_malloc; + ikcp_free_hook = new_free; +} + +// allocate a new kcp segment +static IKCPSEG* ikcp_segment_new(ikcpcb *kcp, int size) +{ + return (IKCPSEG*)ikcp_malloc(sizeof(IKCPSEG) + size); +} + +// delete a segment +static void ikcp_segment_delete(ikcpcb *kcp, IKCPSEG *seg) +{ + ikcp_free(seg); +} + +// write log +void ikcp_log(ikcpcb *kcp, int mask, const char *fmt, ...) +{ + char buffer[1024]; + va_list argptr; + if ((mask & kcp->logmask) == 0 || kcp->writelog == 0) return; + va_start(argptr, fmt); + vsprintf(buffer, fmt, argptr); + va_end(argptr); + kcp->writelog(buffer, kcp, kcp->user); +} + +// check log mask +static int ikcp_canlog(const ikcpcb *kcp, int mask) +{ + if ((mask & kcp->logmask) == 0 || kcp->writelog == NULL) return 0; + return 1; +} + +// output segment +static int ikcp_output(ikcpcb *kcp, const void *data, int size) +{ + assert(kcp); + assert(kcp->output); + if (ikcp_canlog(kcp, IKCP_LOG_OUTPUT)) { + ikcp_log(kcp, IKCP_LOG_OUTPUT, "[RO] %ld bytes", (long)size); + } + if (size == 0) return 0; + return kcp->output((const char*)data, size, kcp, kcp->user); +} + +// output queue +void ikcp_qprint(const char *name, const struct IQUEUEHEAD *head) +{ +#if 0 + const struct IQUEUEHEAD *p; + printf("<%s>: [", name); + for (p = head->next; p != head; p = p->next) { + const IKCPSEG *seg = iqueue_entry(p, const IKCPSEG, node); + printf("(%lu %d)", (unsigned long)seg->sn, (int)(seg->ts % 10000)); + if (p->next != head) printf(","); + } + printf("]\n"); +#endif +} + + +//--------------------------------------------------------------------- +// create a new kcpcb +//--------------------------------------------------------------------- +ikcpcb* ikcp_create(IUINT32 conv, void *user) +{ + ikcpcb *kcp = (ikcpcb*)ikcp_malloc(sizeof(struct IKCPCB)); + if (kcp == NULL) return NULL; + kcp->conv = conv; + kcp->user = user; + kcp->snd_una = 0; + kcp->snd_nxt = 0; + kcp->rcv_nxt = 0; + kcp->ts_recent = 0; + kcp->ts_lastack = 0; + kcp->ts_probe = 0; + kcp->probe_wait = 0; + kcp->snd_wnd = IKCP_WND_SND; + kcp->rcv_wnd = IKCP_WND_RCV; + kcp->rmt_wnd = IKCP_WND_RCV; + kcp->cwnd = 0; + kcp->incr = 0; + kcp->probe = 0; + kcp->mtu = IKCP_MTU_DEF; + kcp->mss = kcp->mtu - IKCP_OVERHEAD; + + kcp->buffer = (char*)ikcp_malloc((kcp->mtu + IKCP_OVERHEAD) * 3); + if (kcp->buffer == NULL) { + ikcp_free(kcp); + return NULL; + } + + iqueue_init(&kcp->snd_queue); + iqueue_init(&kcp->rcv_queue); + iqueue_init(&kcp->snd_buf); + iqueue_init(&kcp->rcv_buf); + kcp->nrcv_buf = 0; + kcp->nsnd_buf = 0; + kcp->nrcv_que = 0; + kcp->nsnd_que = 0; + kcp->state = 0; + kcp->acklist = NULL; + kcp->ackblock = 0; + kcp->ackcount = 0; + kcp->rx_srtt = 0; + kcp->rx_rttval = 0; + kcp->rx_rto = IKCP_RTO_DEF; + kcp->rx_minrto = IKCP_RTO_MIN; + kcp->current = 0; + kcp->interval = IKCP_INTERVAL; + kcp->ts_flush = IKCP_INTERVAL; + kcp->nodelay = 0; + kcp->updated = 0; + kcp->logmask = 0; + kcp->ssthresh = IKCP_THRESH_INIT; + kcp->fastresend = 0; + kcp->nocwnd = 0; + kcp->xmit = 0; + kcp->dead_link = IKCP_DEADLINK; + kcp->output = NULL; + kcp->writelog = NULL; + + return kcp; +} + + +//--------------------------------------------------------------------- +// release a new kcpcb +//--------------------------------------------------------------------- +void ikcp_release(ikcpcb *kcp) +{ + assert(kcp); + if (kcp) { + IKCPSEG *seg; + while (!iqueue_is_empty(&kcp->snd_buf)) { + seg = iqueue_entry(kcp->snd_buf.next, IKCPSEG, node); + iqueue_del(&seg->node); + ikcp_segment_delete(kcp, seg); + } + while (!iqueue_is_empty(&kcp->rcv_buf)) { + seg = iqueue_entry(kcp->rcv_buf.next, IKCPSEG, node); + iqueue_del(&seg->node); + ikcp_segment_delete(kcp, seg); + } + while (!iqueue_is_empty(&kcp->snd_queue)) { + seg = iqueue_entry(kcp->snd_queue.next, IKCPSEG, node); + iqueue_del(&seg->node); + ikcp_segment_delete(kcp, seg); + } + while (!iqueue_is_empty(&kcp->rcv_queue)) { + seg = iqueue_entry(kcp->rcv_queue.next, IKCPSEG, node); + iqueue_del(&seg->node); + ikcp_segment_delete(kcp, seg); + } + if (kcp->buffer) { + ikcp_free(kcp->buffer); + } + if (kcp->acklist) { + ikcp_free(kcp->acklist); + } + + kcp->nrcv_buf = 0; + kcp->nsnd_buf = 0; + kcp->nrcv_que = 0; + kcp->nsnd_que = 0; + kcp->ackcount = 0; + kcp->buffer = NULL; + kcp->acklist = NULL; + ikcp_free(kcp); + } +} + + + +//--------------------------------------------------------------------- +// recv data +//--------------------------------------------------------------------- +int ikcp_recv(ikcpcb *kcp, char *buffer, int len) +{ + struct IQUEUEHEAD *p; + int ispeek = (len < 0)? 1 : 0; + int peeksize; + int recover = 0; + IKCPSEG *seg; + assert(kcp); + + if (iqueue_is_empty(&kcp->rcv_queue)) + return -1; + + if (len < 0) len = -len; + + peeksize = ikcp_peeksize(kcp); + + if (peeksize < 0) + return -2; + + if (peeksize > len) + return -3; + + if (kcp->nrcv_que >= kcp->rcv_wnd) + recover = 1; + + // merge fragment + for (len = 0, p = kcp->rcv_queue.next; p != &kcp->rcv_queue; ) { + int fragment; + seg = iqueue_entry(p, IKCPSEG, node); + p = p->next; + + if (buffer) { + memcpy(buffer, seg->data, seg->len); + buffer += seg->len; + } + + len += seg->len; + fragment = seg->frg; + + if (ikcp_canlog(kcp, IKCP_LOG_RECV)) { + ikcp_log(kcp, IKCP_LOG_RECV, "recv sn=%lu", seg->sn); + } + + if (ispeek == 0) { + iqueue_del(&seg->node); + ikcp_segment_delete(kcp, seg); + kcp->nrcv_que--; + } + + if (fragment == 0) + break; + } + + assert(len == peeksize); + + // move available data from rcv_buf -> rcv_queue + while (! iqueue_is_empty(&kcp->rcv_buf)) { + IKCPSEG *seg = iqueue_entry(kcp->rcv_buf.next, IKCPSEG, node); + if (seg->sn == kcp->rcv_nxt && kcp->nrcv_que < kcp->rcv_wnd) { + iqueue_del(&seg->node); + kcp->nrcv_buf--; + iqueue_add_tail(&seg->node, &kcp->rcv_queue); + kcp->nrcv_que++; + kcp->rcv_nxt++; + } else { + break; + } + } + + // fast recover + if (kcp->nrcv_que < kcp->rcv_wnd && recover) { + // ready to send back IKCP_CMD_WINS in ikcp_flush + // tell remote my window size + kcp->probe |= IKCP_ASK_TELL; + } + + return len; +} + + +//--------------------------------------------------------------------- +// send data +//--------------------------------------------------------------------- +int ikcp_peeksize(const ikcpcb *kcp) +{ + struct IQUEUEHEAD *p; + IKCPSEG *seg; + int length = 0; + + assert(kcp); + + if (iqueue_is_empty(&kcp->rcv_queue)) return -1; + + seg = iqueue_entry(kcp->rcv_queue.next, IKCPSEG, node); + if (seg->frg == 0) return seg->len; + + if (kcp->nrcv_que < seg->frg + 1) return -1; + + for (p = kcp->rcv_queue.next; p != &kcp->rcv_queue; p = p->next) { + seg = iqueue_entry(p, IKCPSEG, node); + length += seg->len; + if (seg->frg == 0) break; + } + + return length; +} + + +//--------------------------------------------------------------------- +// send data +//--------------------------------------------------------------------- +int ikcp_send(ikcpcb *kcp, const char *buffer, int len) +{ + IKCPSEG *seg; + int count, i; + + assert(kcp->mss > 0); + if (len < 0) return -1; + + if (len <= (int)kcp->mss) count = 1; + else count = (len + kcp->mss - 1) / kcp->mss; + + if (count > 255) return -2; + + if (count == 0) count = 1; + + // fragment + for (i = 0; i < count; i++) { + int size = len > (int)kcp->mss ? (int)kcp->mss : len; + seg = ikcp_segment_new(kcp, size); + assert(seg); + if (seg == NULL) { + return -2; + } + if (buffer && len > 0) { + memcpy(seg->data, buffer, size); + } + seg->len = size; + seg->frg = count - i - 1; + iqueue_init(&seg->node); + iqueue_add_tail(&seg->node, &kcp->snd_queue); + kcp->nsnd_que++; + if (buffer) { + buffer += size; + } + len -= size; + } + + return 0; +} + + +//--------------------------------------------------------------------- +// parse ack +//--------------------------------------------------------------------- +static void ikcp_update_ack(ikcpcb *kcp, IINT32 rtt) +{ + IINT32 rto = 0; + if (kcp->rx_srtt == 0) { + kcp->rx_srtt = rtt; + kcp->rx_rttval = rtt / 2; + } else { + long delta = rtt - kcp->rx_srtt; + if (delta < 0) delta = -delta; + kcp->rx_rttval = (3 * kcp->rx_rttval + delta) / 4; + kcp->rx_srtt = (7 * kcp->rx_srtt + rtt) / 8; + if (kcp->rx_srtt < 1) kcp->rx_srtt = 1; + } + rto = kcp->rx_srtt + _imax_(1, 4 * kcp->rx_rttval); + kcp->rx_rto = _ibound_(kcp->rx_minrto, rto, IKCP_RTO_MAX); +} + +static void ikcp_shrink_buf(ikcpcb *kcp) +{ + struct IQUEUEHEAD *p = kcp->snd_buf.next; + if (p != &kcp->snd_buf) { + IKCPSEG *seg = iqueue_entry(p, IKCPSEG, node); + kcp->snd_una = seg->sn; + } else { + kcp->snd_una = kcp->snd_nxt; + } +} + +static void ikcp_parse_ack(ikcpcb *kcp, IUINT32 sn) +{ + struct IQUEUEHEAD *p, *next; + + if (_itimediff(sn, kcp->snd_una) < 0 || _itimediff(sn, kcp->snd_nxt) >= 0) + return; + + for (p = kcp->snd_buf.next; p != &kcp->snd_buf; p = next) { + IKCPSEG *seg = iqueue_entry(p, IKCPSEG, node); + next = p->next; + if (sn == seg->sn) { + iqueue_del(p); + ikcp_segment_delete(kcp, seg); + kcp->nsnd_buf--; + break; + } + else { + seg->fastack++; + } + } +} + +static void ikcp_parse_una(ikcpcb *kcp, IUINT32 una) +{ +#if 1 + struct IQUEUEHEAD *p, *next; + for (p = kcp->snd_buf.next; p != &kcp->snd_buf; p = next) { + IKCPSEG *seg = iqueue_entry(p, IKCPSEG, node); + next = p->next; + if (_itimediff(una, seg->sn) > 0) { + iqueue_del(p); + ikcp_segment_delete(kcp, seg); + kcp->nsnd_buf--; + } else { + break; + } + } +#endif +} + + +//--------------------------------------------------------------------- +// ack append +//--------------------------------------------------------------------- +static void ikcp_ack_push(ikcpcb *kcp, IUINT32 sn, IUINT32 ts) +{ + size_t newsize = kcp->ackcount + 1; + IUINT32 *ptr; + + if (newsize > kcp->ackblock) { + IUINT32 *acklist; + size_t newblock; + + for (newblock = 8; newblock < newsize; newblock <<= 1); + acklist = (IUINT32*)ikcp_malloc(newblock * sizeof(IUINT32) * 2); + + if (acklist == NULL) { + assert(acklist != NULL); + abort(); + } + + if (kcp->acklist != NULL) { + size_t x; + for (x = 0; x < kcp->ackcount; x++) { + acklist[x * 2 + 0] = kcp->acklist[x * 2 + 0]; + acklist[x * 2 + 1] = kcp->acklist[x * 2 + 1]; + } + ikcp_free(kcp->acklist); + } + + kcp->acklist = acklist; + kcp->ackblock = newblock; + } + + ptr = &kcp->acklist[kcp->ackcount * 2]; + ptr[0] = sn; + ptr[1] = ts; + kcp->ackcount++; +} + +static void ikcp_ack_get(const ikcpcb *kcp, int p, IUINT32 *sn, IUINT32 *ts) +{ + if (sn) sn[0] = kcp->acklist[p * 2 + 0]; + if (ts) ts[0] = kcp->acklist[p * 2 + 1]; +} + + +//--------------------------------------------------------------------- +// parse data +//--------------------------------------------------------------------- +void ikcp_parse_data(ikcpcb *kcp, IKCPSEG *newseg) +{ + struct IQUEUEHEAD *p, *prev; + IUINT32 sn = newseg->sn; + int repeat = 0; + + if (_itimediff(sn, kcp->rcv_nxt + kcp->rcv_wnd) >= 0 || + _itimediff(sn, kcp->rcv_nxt) < 0) { + ikcp_segment_delete(kcp, newseg); + return; + } + + for (p = kcp->rcv_buf.prev; p != &kcp->rcv_buf; p = prev) { + IKCPSEG *seg = iqueue_entry(p, IKCPSEG, node); + prev = p->prev; + if (seg->sn == sn) { + repeat = 1; + break; + } + if (_itimediff(sn, seg->sn) > 0) { + break; + } + } + + if (repeat == 0) { + iqueue_init(&newseg->node); + iqueue_add(&newseg->node, p); + kcp->nrcv_buf++; + } else { + ikcp_segment_delete(kcp, newseg); + } + +#if 0 + ikcp_qprint("rcvbuf", &kcp->rcv_buf); + printf("rcv_nxt=%lu\n", kcp->rcv_nxt); +#endif + + // move available data from rcv_buf -> rcv_queue + while (! iqueue_is_empty(&kcp->rcv_buf)) { + IKCPSEG *seg = iqueue_entry(kcp->rcv_buf.next, IKCPSEG, node); + if (seg->sn == kcp->rcv_nxt && kcp->nrcv_que < kcp->rcv_wnd) { + iqueue_del(&seg->node); + kcp->nrcv_buf--; + iqueue_add_tail(&seg->node, &kcp->rcv_queue); + kcp->nrcv_que++; + kcp->rcv_nxt++; + } else { + break; + } + } + +#if 0 + ikcp_qprint("queue", &kcp->rcv_queue); + printf("rcv_nxt=%lu\n", kcp->rcv_nxt); +#endif + +#if 1 +// printf("snd(buf=%d, queue=%d)\n", kcp->nsnd_buf, kcp->nsnd_que); +// printf("rcv(buf=%d, queue=%d)\n", kcp->nrcv_buf, kcp->nrcv_que); +#endif +} + + +//--------------------------------------------------------------------- +// input data +//--------------------------------------------------------------------- +int ikcp_input(ikcpcb *kcp, const char *data, long size) +{ + IUINT32 una = kcp->snd_una; + + if (ikcp_canlog(kcp, IKCP_LOG_INPUT)) { + ikcp_log(kcp, IKCP_LOG_INPUT, "[RI] %d bytes", size); + } + + if (data == NULL || size < 24) return 0; + + while (1) { + IUINT32 ts, sn, len, una, conv; + IUINT16 wnd; + IUINT8 cmd, frg; + IKCPSEG *seg; + + if (size < (int)IKCP_OVERHEAD) break; + + data = ikcp_decode32u(data, &conv); + if (conv != kcp->conv) return -1; + + data = ikcp_decode8u(data, &cmd); + data = ikcp_decode8u(data, &frg); + data = ikcp_decode16u(data, &wnd); + data = ikcp_decode32u(data, &ts); + data = ikcp_decode32u(data, &sn); + data = ikcp_decode32u(data, &una); + data = ikcp_decode32u(data, &len); + + size -= IKCP_OVERHEAD; + + if ((long)size < (long)len) return -2; + + if (cmd != IKCP_CMD_PUSH && cmd != IKCP_CMD_ACK && + cmd != IKCP_CMD_WASK && cmd != IKCP_CMD_WINS) + return -3; + + kcp->rmt_wnd = wnd; + ikcp_parse_una(kcp, una); + ikcp_shrink_buf(kcp); + + if (cmd == IKCP_CMD_ACK) { + if (_itimediff(kcp->current, ts) >= 0) { + ikcp_update_ack(kcp, _itimediff(kcp->current, ts)); + } + ikcp_parse_ack(kcp, sn); + ikcp_shrink_buf(kcp); + if (ikcp_canlog(kcp, IKCP_LOG_IN_ACK)) { + ikcp_log(kcp, IKCP_LOG_IN_DATA, + "input ack: sn=%lu rtt=%ld rto=%ld", sn, + (long)_itimediff(kcp->current, ts), + (long)kcp->rx_rto); + } + } + else if (cmd == IKCP_CMD_PUSH) { + if (ikcp_canlog(kcp, IKCP_LOG_IN_DATA)) { + ikcp_log(kcp, IKCP_LOG_IN_DATA, + "input psh: sn=%lu ts=%lu", sn, ts); + } + if (_itimediff(sn, kcp->rcv_nxt + kcp->rcv_wnd) < 0) { + ikcp_ack_push(kcp, sn, ts); + if (_itimediff(sn, kcp->rcv_nxt) >= 0) { + seg = ikcp_segment_new(kcp, len); + seg->conv = conv; + seg->cmd = cmd; + seg->frg = frg; + seg->wnd = wnd; + seg->ts = ts; + seg->sn = sn; + seg->una = una; + seg->len = len; + + if (len > 0) { + memcpy(seg->data, data, len); + } + + ikcp_parse_data(kcp, seg); + } + } + } + else if (cmd == IKCP_CMD_WASK) { + // ready to send back IKCP_CMD_WINS in ikcp_flush + // tell remote my window size + kcp->probe |= IKCP_ASK_TELL; + if (ikcp_canlog(kcp, IKCP_LOG_IN_PROBE)) { + ikcp_log(kcp, IKCP_LOG_IN_PROBE, "input probe"); + } + } + else if (cmd == IKCP_CMD_WINS) { + // do nothing + if (ikcp_canlog(kcp, IKCP_LOG_IN_WINS)) { + ikcp_log(kcp, IKCP_LOG_IN_WINS, + "input wins: %lu", (IUINT32)(wnd)); + } + } + else { + return -3; + } + + data += len; + size -= len; + } + + if (_itimediff(kcp->snd_una, una) > 0) { + if (kcp->cwnd < kcp->rmt_wnd) { + IUINT32 mss = kcp->mss; + if (kcp->cwnd < kcp->ssthresh) { + kcp->cwnd++; + kcp->incr += mss; + } else { + if (kcp->incr < mss) kcp->incr = mss; + kcp->incr += (mss * mss) / kcp->incr + (mss / 16); + if ((kcp->cwnd + 1) * mss >= kcp->incr) { + kcp->cwnd++; + } + } + if (kcp->cwnd > kcp->rmt_wnd) { + kcp->cwnd = kcp->rmt_wnd; + kcp->incr = kcp->rmt_wnd * mss; + } + } + } + + return 0; +} + + +//--------------------------------------------------------------------- +// ikcp_encode_seg +//--------------------------------------------------------------------- +static char *ikcp_encode_seg(char *ptr, const IKCPSEG *seg) +{ + ptr = ikcp_encode32u(ptr, seg->conv); + ptr = ikcp_encode8u(ptr, (IUINT8)seg->cmd); + ptr = ikcp_encode8u(ptr, (IUINT8)seg->frg); + ptr = ikcp_encode16u(ptr, (IUINT16)seg->wnd); + ptr = ikcp_encode32u(ptr, seg->ts); + ptr = ikcp_encode32u(ptr, seg->sn); + ptr = ikcp_encode32u(ptr, seg->una); + ptr = ikcp_encode32u(ptr, seg->len); + return ptr; +} + +static int ikcp_wnd_unused(const ikcpcb *kcp) +{ + if (kcp->nrcv_que < kcp->rcv_wnd) { + return kcp->rcv_wnd - kcp->nrcv_que; + } + return 0; +} + + +//--------------------------------------------------------------------- +// ikcp_flush +//--------------------------------------------------------------------- +void ikcp_flush(ikcpcb *kcp) +{ + IUINT32 current = kcp->current; + char *buffer = kcp->buffer; + char *ptr = buffer; + int count, size, i; + IUINT32 resent, cwnd; + IUINT32 rtomin; + struct IQUEUEHEAD *p; + int change = 0; + int lost = 0; + IKCPSEG seg; + + // 'ikcp_update' haven't been called. + if (kcp->updated == 0) return; + + seg.conv = kcp->conv; + seg.cmd = IKCP_CMD_ACK; + seg.frg = 0; + seg.wnd = ikcp_wnd_unused(kcp); + seg.una = kcp->rcv_nxt; + seg.len = 0; + seg.sn = 0; + seg.ts = 0; + + // flush acknowledges + count = kcp->ackcount; + for (i = 0; i < count; i++) { + size = (int)(ptr - buffer); + if (size > (int)kcp->mtu) { + ikcp_output(kcp, buffer, size); + ptr = buffer; + } + ikcp_ack_get(kcp, i, &seg.sn, &seg.ts); + ptr = ikcp_encode_seg(ptr, &seg); + } + + kcp->ackcount = 0; + + // probe window size (if remote window size equals zero) + if (kcp->rmt_wnd == 0) { + if (kcp->probe_wait == 0) { + kcp->probe_wait = IKCP_PROBE_INIT; + kcp->ts_probe = kcp->current + kcp->probe_wait; + } + else { + if (_itimediff(kcp->current, kcp->ts_probe) >= 0) { + if (kcp->probe_wait < IKCP_PROBE_INIT) + kcp->probe_wait = IKCP_PROBE_INIT; + kcp->probe_wait += kcp->probe_wait / 2; + if (kcp->probe_wait > IKCP_PROBE_LIMIT) + kcp->probe_wait = IKCP_PROBE_LIMIT; + kcp->ts_probe = kcp->current + kcp->probe_wait; + kcp->probe |= IKCP_ASK_SEND; + } + } + } else { + kcp->ts_probe = 0; + kcp->probe_wait = 0; + } + + // flush window probing commands + if (kcp->probe & IKCP_ASK_SEND) { + seg.cmd = IKCP_CMD_WASK; + size = (int)(ptr - buffer); + if (size > (int)kcp->mtu) { + ikcp_output(kcp, buffer, size); + ptr = buffer; + } + ptr = ikcp_encode_seg(ptr, &seg); + } + + // flush window probing commands + if (kcp->probe & IKCP_ASK_TELL) { + seg.cmd = IKCP_CMD_WINS; + size = (int)(ptr - buffer); + if (size > (int)kcp->mtu) { + ikcp_output(kcp, buffer, size); + ptr = buffer; + } + ptr = ikcp_encode_seg(ptr, &seg); + } + + kcp->probe = 0; + + // calculate window size + cwnd = _imin_(kcp->snd_wnd, kcp->rmt_wnd); + if (kcp->nocwnd == 0) cwnd = _imin_(kcp->cwnd, cwnd); + + // move data from snd_queue to snd_buf + while (_itimediff(kcp->snd_nxt, kcp->snd_una + cwnd) < 0) { + IKCPSEG *newseg; + if (iqueue_is_empty(&kcp->snd_queue)) break; + + newseg = iqueue_entry(kcp->snd_queue.next, IKCPSEG, node); + + iqueue_del(&newseg->node); + iqueue_add_tail(&newseg->node, &kcp->snd_buf); + kcp->nsnd_que--; + kcp->nsnd_buf++; + + newseg->conv = kcp->conv; + newseg->cmd = IKCP_CMD_PUSH; + newseg->wnd = seg.wnd; + newseg->ts = current; + newseg->sn = kcp->snd_nxt++; + newseg->una = kcp->rcv_nxt; + newseg->resendts = current; + newseg->rto = kcp->rx_rto; + newseg->fastack = 0; + newseg->xmit = 0; + } + + // calculate resent + resent = (kcp->fastresend > 0)? (IUINT32)kcp->fastresend : 0xffffffff; + rtomin = (kcp->nodelay == 0)? (kcp->rx_rto >> 3) : 0; + + // flush data segments + for (p = kcp->snd_buf.next; p != &kcp->snd_buf; p = p->next) { + IKCPSEG *segment = iqueue_entry(p, IKCPSEG, node); + int needsend = 0; + if (segment->xmit == 0) { + needsend = 1; + segment->xmit++; + segment->rto = kcp->rx_rto; + segment->resendts = current + segment->rto + rtomin; + } + else if (_itimediff(current, segment->resendts) >= 0) { + needsend = 1; + segment->xmit++; + kcp->xmit++; + if (kcp->nodelay == 0) { + segment->rto += kcp->rx_rto; + } else { + segment->rto += kcp->rx_rto / 2; + } + segment->resendts = current + segment->rto; + lost = 1; + } + else if (segment->fastack >= resent) { + needsend = 1; + segment->xmit++; + segment->fastack = 0; + segment->resendts = current + segment->rto; + change++; + } + + if (needsend) { + int size, need; + segment->ts = current; + segment->wnd = seg.wnd; + segment->una = kcp->rcv_nxt; + + size = (int)(ptr - buffer); + need = IKCP_OVERHEAD + segment->len; + + if (size + need >= (int)kcp->mtu) { + ikcp_output(kcp, buffer, size); + ptr = buffer; + } + + ptr = ikcp_encode_seg(ptr, segment); + + if (segment->len > 0) { + memcpy(ptr, segment->data, segment->len); + ptr += segment->len; + } + + if (segment->xmit >= kcp->dead_link) { + kcp->state = -1; + } + } + } + + // flash remain segments + size = (int)(ptr - buffer); + if (size > 0) { + ikcp_output(kcp, buffer, size); + } + + // update ssthresh + if (change) { + IUINT32 inflight = kcp->snd_nxt - kcp->snd_una; + kcp->ssthresh = inflight / 2; + if (kcp->ssthresh < IKCP_THRESH_MIN) + kcp->ssthresh = IKCP_THRESH_MIN; + kcp->cwnd = kcp->ssthresh + resent; + kcp->incr = kcp->cwnd * kcp->mss; + } + + if (lost) { + kcp->ssthresh = cwnd / 2; + if (kcp->ssthresh < IKCP_THRESH_MIN) + kcp->ssthresh = IKCP_THRESH_MIN; + kcp->cwnd = 1; + kcp->incr = kcp->mss; + } + + if (kcp->cwnd < 1) { + kcp->cwnd = 1; + kcp->incr = kcp->mss; + } +} + + +//--------------------------------------------------------------------- +// input update +//--------------------------------------------------------------------- +void ikcp_update(ikcpcb *kcp, IUINT32 current) +{ + IINT32 slap; + + kcp->current = current; + + if (kcp->updated == 0) { + kcp->updated = 1; + kcp->ts_flush = kcp->current; + } + + slap = _itimediff(kcp->current, kcp->ts_flush); + + if (slap >= 10000 || slap < -10000) { + kcp->ts_flush = kcp->current; + slap = 0; + } + + if (slap >= 0) { + kcp->ts_flush += kcp->interval; + if (_itimediff(kcp->current, kcp->ts_flush) >= 0) { + kcp->ts_flush = kcp->current + kcp->interval; + } + ikcp_flush(kcp); + } +} + + +IUINT32 ikcp_check(const ikcpcb *kcp, IUINT32 current) +{ + IUINT32 ts_flush = kcp->ts_flush; + IINT32 tm_flush = 0x7fffffff; + IINT32 tm_packet = 0x7fffffff; + IUINT32 minimal = 0; + struct IQUEUEHEAD *p; + + if (kcp->updated == 0) { + return current; + } + + if (_itimediff(current, ts_flush) >= 10000 || + _itimediff(current, ts_flush) < -10000) { + ts_flush = current; + } + + if (_itimediff(current, ts_flush) >= 0) { + return current; + } + + tm_flush = _itimediff(ts_flush, current); + + for (p = kcp->snd_buf.next; p != &kcp->snd_buf; p = p->next) { + const IKCPSEG *seg = iqueue_entry(p, const IKCPSEG, node); + IINT32 diff = _itimediff(seg->resendts, current); + if (diff <= 0) { + return current; + } + if (diff < tm_packet) tm_packet = diff; + } + + minimal = (IUINT32)(tm_packet < tm_flush ? tm_packet : tm_flush); + if (minimal >= kcp->interval) minimal = kcp->interval; + + return current + minimal; +} + + + +int ikcp_setmtu(ikcpcb *kcp, int mtu) +{ + char *buffer; + if (mtu < 50 || mtu < (int)IKCP_OVERHEAD) + return -1; + buffer = (char*)ikcp_malloc((mtu + IKCP_OVERHEAD) * 3); + if (buffer == NULL) + return -2; + kcp->mtu = mtu; + kcp->mss = kcp->mtu - IKCP_OVERHEAD; + ikcp_free(kcp->buffer); + kcp->buffer = buffer; + return 0; +} + +int ikcp_interval(ikcpcb *kcp, int interval) +{ + if (interval > 5000) interval = 5000; + else if (interval < 10) interval = 10; + kcp->interval = interval; + return 0; +} + +int ikcp_nodelay(ikcpcb *kcp, int nodelay, int interval, int resend, int nc) +{ + if (nodelay >= 0) { + kcp->nodelay = nodelay; + if (nodelay) { + kcp->rx_minrto = IKCP_RTO_NDL; + } + else { + kcp->rx_minrto = IKCP_RTO_MIN; + } + } + if (interval >= 0) { + if (interval > 5000) interval = 5000; + else if (interval < 10) interval = 10; + kcp->interval = interval; + } + if (resend >= 0) { + kcp->fastresend = resend; + } + if (nc >= 0) { + kcp->nocwnd = nc; + } + return 0; +} + + +int ikcp_wndsize(ikcpcb *kcp, int sndwnd, int rcvwnd) +{ + if (kcp) { + if (sndwnd > 0) { + kcp->snd_wnd = sndwnd; + } + if (rcvwnd > 0) { + kcp->rcv_wnd = rcvwnd; + } + } + return 0; +} + +int ikcp_waitsnd(const ikcpcb *kcp) +{ + return kcp->nsnd_buf + kcp->nsnd_que; +} + + diff --git a/ikcp.h b/ikcp.h new file mode 100644 index 0000000..54d395c --- /dev/null +++ b/ikcp.h @@ -0,0 +1,379 @@ +//===================================================================== +// +// KCP - A Better ARQ Protocol Implementation +// skywind3000 (at) gmail.com, 2010-2011 +// +// Features: +// + Average RTT reduce 30% - 40% vs traditional ARQ like tcp. +// + Maximum RTT reduce three times vs tcp. +// + Lightweight, distributed as a single source file. +// +//===================================================================== +#ifndef __IKCP_H__ +#define __IKCP_H__ + +#include +#include +#include + + +//===================================================================== +// 32BIT INTEGER DEFINITION +//===================================================================== +#ifndef __INTEGER_32_BITS__ +#define __INTEGER_32_BITS__ +#if defined(_WIN64) || defined(WIN64) || defined(__amd64__) || \ + defined(__x86_64) || defined(__x86_64__) || defined(_M_IA64) || \ + defined(_M_AMD64) + typedef unsigned int ISTDUINT32; + typedef int ISTDINT32; +#elif defined(_WIN32) || defined(WIN32) || defined(__i386__) || \ + defined(__i386) || defined(_M_X86) + typedef unsigned long ISTDUINT32; + typedef long ISTDINT32; +#elif defined(__MACOS__) + typedef UInt32 ISTDUINT32; + typedef SInt32 ISTDINT32; +#elif defined(__APPLE__) && defined(__MACH__) + #include + typedef u_int32_t ISTDUINT32; + typedef int32_t ISTDINT32; +#elif defined(__BEOS__) + #include + typedef u_int32_t ISTDUINT32; + typedef int32_t ISTDINT32; +#elif (defined(_MSC_VER) || defined(__BORLANDC__)) && (!defined(__MSDOS__)) + typedef unsigned __int32 ISTDUINT32; + typedef __int32 ISTDINT32; +#elif defined(__GNUC__) + #include + typedef uint32_t ISTDUINT32; + typedef int32_t ISTDINT32; +#else + typedef unsigned long ISTDUINT32; + typedef long ISTDINT32; +#endif +#endif + + +//===================================================================== +// Integer Definition +//===================================================================== +#ifndef __IINT8_DEFINED +#define __IINT8_DEFINED +typedef char IINT8; +#endif + +#ifndef __IUINT8_DEFINED +#define __IUINT8_DEFINED +typedef unsigned char IUINT8; +#endif + +#ifndef __IUINT16_DEFINED +#define __IUINT16_DEFINED +typedef unsigned short IUINT16; +#endif + +#ifndef __IINT16_DEFINED +#define __IINT16_DEFINED +typedef short IINT16; +#endif + +#ifndef __IINT32_DEFINED +#define __IINT32_DEFINED +typedef ISTDINT32 IINT32; +#endif + +#ifndef __IUINT32_DEFINED +#define __IUINT32_DEFINED +typedef ISTDUINT32 IUINT32; +#endif + +#ifndef __IINT64_DEFINED +#define __IINT64_DEFINED +#if defined(_MSC_VER) || defined(__BORLANDC__) +typedef __int64 IINT64; +#else +typedef long long IINT64; +#endif +#endif + +#ifndef __IUINT64_DEFINED +#define __IUINT64_DEFINED +#if defined(_MSC_VER) || defined(__BORLANDC__) +typedef unsigned __int64 IUINT64; +#else +typedef unsigned long long IUINT64; +#endif +#endif + +#ifndef INLINE +#if defined(__GNUC__) + +#if (__GNUC__ > 3) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 1)) +#define INLINE __inline__ __attribute__((always_inline)) +#else +#define INLINE __inline__ +#endif + +#elif (defined(_MSC_VER) || defined(__BORLANDC__) || defined(__WATCOMC__)) +#define INLINE __inline +#else +#define INLINE +#endif +#endif + +#ifndef inline +#define inline INLINE +#endif + + +//===================================================================== +// QUEUE DEFINITION +//===================================================================== +#ifndef __IQUEUE_DEF__ +#define __IQUEUE_DEF__ + +struct IQUEUEHEAD { + struct IQUEUEHEAD *next, *prev; +}; + +typedef struct IQUEUEHEAD iqueue_head; + + +//--------------------------------------------------------------------- +// queue init +//--------------------------------------------------------------------- +#define IQUEUE_HEAD_INIT(name) { &(name), &(name) } +#define IQUEUE_HEAD(name) \ + struct IQUEUEHEAD name = IQUEUE_HEAD_INIT(name) + +#define IQUEUE_INIT(ptr) ( \ + (ptr)->next = (ptr), (ptr)->prev = (ptr)) + +#define IOFFSETOF(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) + +#define ICONTAINEROF(ptr, type, member) ( \ + (type*)( ((char*)((type*)ptr)) - IOFFSETOF(type, member)) ) + +#define IQUEUE_ENTRY(ptr, type, member) ICONTAINEROF(ptr, type, member) + + +//--------------------------------------------------------------------- +// queue operation +//--------------------------------------------------------------------- +#define IQUEUE_ADD(node, head) ( \ + (node)->prev = (head), (node)->next = (head)->next, \ + (head)->next->prev = (node), (head)->next = (node)) + +#define IQUEUE_ADD_TAIL(node, head) ( \ + (node)->prev = (head)->prev, (node)->next = (head), \ + (head)->prev->next = (node), (head)->prev = (node)) + +#define IQUEUE_DEL_BETWEEN(p, n) ((n)->prev = (p), (p)->next = (n)) + +#define IQUEUE_DEL(entry) (\ + (entry)->next->prev = (entry)->prev, \ + (entry)->prev->next = (entry)->next, \ + (entry)->next = 0, (entry)->prev = 0) + +#define IQUEUE_DEL_INIT(entry) do { \ + IQUEUE_DEL(entry); IQUEUE_INIT(entry); } while (0) + +#define IQUEUE_IS_EMPTY(entry) ((entry) == (entry)->next) + +#define iqueue_init IQUEUE_INIT +#define iqueue_entry IQUEUE_ENTRY +#define iqueue_add IQUEUE_ADD +#define iqueue_add_tail IQUEUE_ADD_TAIL +#define iqueue_del IQUEUE_DEL +#define iqueue_del_init IQUEUE_DEL_INIT +#define iqueue_is_empty IQUEUE_IS_EMPTY + +#define IQUEUE_FOREACH(iterator, head, TYPE, MEMBER) \ + for ((iterator) = iqueue_entry((head)->next, TYPE, MEMBER); \ + &((iterator)->MEMBER) != (head); \ + (iterator) = iqueue_entry((iterator)->MEMBER.next, TYPE, MEMBER)) + +#define iqueue_foreach(iterator, head, TYPE, MEMBER) \ + IQUEUE_FOREACH(iterator, head, TYPE, MEMBER) + +#define iqueue_foreach_entry(pos, head) \ + for( (pos) = (head)->next; (pos) != (head) ; (pos) = (pos)->next ) + + +#define __iqueue_splice(list, head) do { \ + iqueue_head *first = (list)->next, *last = (list)->prev; \ + iqueue_head *at = (head)->next; \ + (first)->prev = (head), (head)->next = (first); \ + (last)->next = (at), (at)->prev = (last); } while (0) + +#define iqueue_splice(list, head) do { \ + if (!iqueue_is_empty(list)) __iqueue_splice(list, head); } while (0) + +#define iqueue_splice_init(list, head) do { \ + iqueue_splice(list, head); iqueue_init(list); } while (0) + + +#ifdef _MSC_VER +#pragma warning(disable:4311) +#pragma warning(disable:4312) +#pragma warning(disable:4996) +#endif + +#endif + + +//--------------------------------------------------------------------- +// WORD ORDER +//--------------------------------------------------------------------- +#ifndef IWORDS_BIG_ENDIAN + #ifdef _BIG_ENDIAN_ + #if _BIG_ENDIAN_ + #define IWORDS_BIG_ENDIAN 1 + #endif + #endif + #ifndef IWORDS_BIG_ENDIAN + #if defined(__hppa__) || \ + defined(__m68k__) || defined(mc68000) || defined(_M_M68K) || \ + (defined(__MIPS__) && defined(__MISPEB__)) || \ + defined(__ppc__) || defined(__POWERPC__) || defined(_M_PPC) || \ + defined(__sparc__) + #define IWORDS_BIG_ENDIAN 1 + #endif + #endif + #ifndef IWORDS_BIG_ENDIAN + #define IWORDS_BIG_ENDIAN 0 + #endif +#endif + + + +//===================================================================== +// SEGMENT +//===================================================================== +struct IKCPSEG +{ + struct IQUEUEHEAD node; + IUINT32 conv; + IUINT32 cmd; + IUINT32 frg; + IUINT32 wnd; + IUINT32 ts; + IUINT32 sn; + IUINT32 una; + IUINT32 len; + IUINT32 resendts; + IUINT32 rto; + IUINT32 fastack; + IUINT32 xmit; + char data[1]; +}; + + +//--------------------------------------------------------------------- +// IKCPCB +//--------------------------------------------------------------------- +struct IKCPCB +{ + IUINT32 conv, mtu, mss, state; + IUINT32 snd_una, snd_nxt, rcv_nxt; + IUINT32 ts_recent, ts_lastack, ssthresh; + IINT32 rx_rttval, rx_srtt, rx_rto, rx_minrto; + IUINT32 snd_wnd, rcv_wnd, rmt_wnd, cwnd, probe; + IUINT32 current, interval, ts_flush, xmit; + IUINT32 nrcv_buf, nsnd_buf; + IUINT32 nrcv_que, nsnd_que; + IUINT32 nodelay, updated; + IUINT32 ts_probe, probe_wait; + IUINT32 dead_link, incr; + struct IQUEUEHEAD snd_queue; + struct IQUEUEHEAD rcv_queue; + struct IQUEUEHEAD snd_buf; + struct IQUEUEHEAD rcv_buf; + IUINT32 *acklist; + IUINT32 ackcount; + IUINT32 ackblock; + void *user; + char *buffer; + int fastresend; + int nocwnd; + int logmask; + int (*output)(const char *buf, int len, struct IKCPCB *kcp, void *user); + void (*writelog)(const char *log, struct IKCPCB *kcp, void *user); +}; + + +typedef struct IKCPCB ikcpcb; + +#define IKCP_LOG_OUTPUT 1 +#define IKCP_LOG_INPUT 2 +#define IKCP_LOG_SEND 4 +#define IKCP_LOG_RECV 8 +#define IKCP_LOG_IN_DATA 16 +#define IKCP_LOG_IN_ACK 32 +#define IKCP_LOG_IN_PROBE 64 +#define IKCP_LOG_IN_WINS 128 +#define IKCP_LOG_OUT_DATA 256 +#define IKCP_LOG_OUT_ACK 512 +#define IKCP_LOG_OUT_PROBE 1024 +#define IKCP_LOG_OUT_WINS 2048 + +#ifdef __cplusplus +extern "C" { +#endif + +//--------------------------------------------------------------------- +// interface +//--------------------------------------------------------------------- + +// create a new kcp control object, 'conv' must equal in two endpoint +// from the same connection. 'user' will be passed to the output callback +// output callback can be setup like this: 'kcp->output = my_udp_output' +ikcpcb* ikcp_create(IUINT32 conv, void *user); + +// release kcp control object +void ikcp_release(ikcpcb *kcp); + +int ikcp_recv(ikcpcb *kcp, char *buffer, int len); +int ikcp_send(ikcpcb *kcp, const char *buffer, int len); + +// update state (call it repeatedly, every 10ms-100ms) +// 'current' - current timestamp in millisec +void ikcp_update(ikcpcb *kcp, IUINT32 current); +IUINT32 ikcp_check(const ikcpcb *kcp, IUINT32 current); + +// when you received a low level packet (eg. UDP packet), call it +int ikcp_input(ikcpcb *kcp, const char *data, long size); +void ikcp_flush(ikcpcb *kcp); + +int ikcp_peeksize(const ikcpcb *kcp); + +// change MTU size, default is 14000 +int ikcp_setmtu(ikcpcb *kcp, int mtu); + +// set maximum window size: sndwnd=32, rcvwnd=32 by default +int ikcp_wndsize(ikcpcb *kcp, int sndwnd, int rcvwnd); + +// get how many packet is waiting to be sent +int ikcp_waitsnd(const ikcpcb *kcp); + +// fastest: ikcp_nodelay(kcp, 1, 20, 2, 1) +// nodelay: 0:disable(default), 1:enable +// interval: internal update timer interval in millisec, default is 100ms +// resend: 0:disable fast resend(default), 1:enable fast resend +// nc: 0:normal congestion control(default), 1:disable congestion control +int ikcp_nodelay(ikcpcb *kcp, int nodelay, int interval, int resend, int nc); + +int ikcp_rcvbuf_count(const ikcpcb *kcp); +int ikcp_sndbuf_count(const ikcpcb *kcp); + +void ikcp_log(ikcpcb *kcp, int mask, const char *fmt, ...); + +#ifdef __cplusplus +} +#endif + +#endif + + diff --git a/test.cpp b/test.cpp new file mode 100644 index 0000000..34f009d --- /dev/null +++ b/test.cpp @@ -0,0 +1,177 @@ +//===================================================================== +// +// test.cpp - kcp 测试用例 +// +// 说明： +// gcc test.cpp -o test -lstdc++ +// +//===================================================================== + +#include +#include + +#include "test.h" +#include "ikcp.c" + + +// 模拟网络 +LatencySimulator *vnet; + +// 模拟网络：模拟发送一个 udp包 +int udp_output(const char *buf, int len, ikcpcb *kcp, void *user) +{ + int id = (int)user; + vnet->send(id, buf, len); + return 0; +} + +// 测试用例 +void test(int mode) +{ + // 创建模拟网络：丢包率10%，Rtt 60ms~125ms + vnet = new LatencySimulator(10, 60, 125); + + // 创建两个端点的 kcp对象，第一个参数 conv是会话编号，同一个会话需要相同 + // 最后一个是 user参数，用来传递标识 + ikcpcb *kcp1 = ikcp_create(0x11223344, (void*)0); + ikcpcb *kcp2 = ikcp_create(0x11223344, (void*)1); + + // 设置kcp的下层输出，这里为 udp_output，模拟udp网络输出函数 + kcp1->output = udp_output; + kcp2->output = udp_output; + + IUINT32 current = iclock(); + IUINT32 slap = current + 20; + IUINT32 index = 0; + IUINT32 next = 0; + IINT64 sumrtt = 0; + int count = 0; + int maxrtt = 0; + + // 配置窗口大小：平均延迟200ms，每20ms发送一个包， + // 而考虑到丢包重发，设置最大收发窗口为128 + ikcp_wndsize(kcp1, 128, 128); + ikcp_wndsize(kcp2, 128, 128); + + // 判断测试用例的模式 + if (mode == 0) { + // 默认模式 + ikcp_nodelay(kcp1, 0, 10, 0, 0); + ikcp_nodelay(kcp2, 0, 10, 0, 0); + } + else if (mode == 1) { + // 普通模式，关闭流控等 + ikcp_nodelay(kcp1, 0, 10, 0, 1); + ikcp_nodelay(kcp2, 0, 10, 0, 1); + } else { + // 启动快速模式 + // 第二个参数 nodelay-启用以后若干常规加速将启动 + // 第三个参数 interval为内部处理时钟，默认设置为 10ms + // 第四个参数 resend为快速重传指标，设置为2 + // 第五个参数 为是否禁用常规流控，这里禁止 + ikcp_nodelay(kcp1, 1, 10, 2, 1); + ikcp_nodelay(kcp2, 1, 10, 2, 1); + } + + + char buffer[2000]; + int hr; + + IUINT32 ts1 = iclock(); + + while (1) { + isleep(1); + current = iclock(); + ikcp_update(kcp1, iclock()); + ikcp_update(kcp2, iclock()); + + // 每隔 20ms，kcp1发送数据 + for (; current >= slap; slap += 20) { + *(IUINT32*)(buffer + 0) = index++; + *(IUINT32*)(buffer + 4) = current; + + // 发送上层协议包 + ikcp_send(kcp1, buffer, 8); + } + + // 处理虚拟网络：检测是否有udp包从p1->p2 + while (1) { + hr = vnet->recv(1, buffer, 2000); + if (hr < 0) break; + // 如果 p2收到udp，则作为下层协议输入到kcp2 + ikcp_input(kcp2, buffer, hr); + } + + // 处理虚拟网络：检测是否有udp包从p2->p1 + while (1) { + hr = vnet->recv(0, buffer, 2000); + if (hr < 0) break; + // 如果 p1收到udp，则作为下层协议输入到kcp1 + ikcp_input(kcp1, buffer, hr); + } + + // kcp2接收到任何包都返回回去 + while (1) { + hr = ikcp_recv(kcp2, buffer, 10); + // 没有收到包就退出 + if (hr < 0) break; + // 如果收到包就回射 + ikcp_send(kcp2, buffer, hr); + } + + // kcp1收到kcp2的回射数据 + while (1) { + hr = ikcp_recv(kcp1, buffer, 10); + // 没有收到包就退出 + if (hr < 0) break; + IUINT32 sn = *(IUINT32*)(buffer + 0); + IUINT32 ts = *(IUINT32*)(buffer + 4); + IUINT32 rtt = current - ts; + + if (sn != next) { + // 如果收到的包不连续 + printf("ERROR sn %d<->%d\n", (int)count, (int)next); + return; + } + + next++; + sumrtt += rtt; + count++; + if (rtt > maxrtt) maxrtt = rtt; + + printf("[RECV] mode=%d sn=%d rtt=%d\n", mode, (int)sn, (int)rtt); + } + if (next > 1000) break; + } + + ts1 = iclock() - ts1; + + ikcp_release(kcp1); + ikcp_release(kcp2); + + const char *names[3] = { "default", "normal", "fast" }; + printf("%s mode result (%dms):\n", names[mode], ts1); + printf("avgrtt=%d maxrtt=%d\n", (int)(sumrtt / count), maxrtt); + printf("press enter to next ...\n"); + char ch; scanf("%c", &ch); +} + +int main() +{ + test(0); // 默认模式，类似 TCP：正常模式，无快速重传，常规流控 + test(1); // 普通模式，关闭流控等 + test(2); // 快速模式，所有开关都打开，且关闭流控 + return 0; +} + +/* +default mode result (20917ms): +avgrtt=740 maxrtt=1507 + +normal mode result (20131ms): +avgrtt=156 maxrtt=571 + +fast mode result (20207ms): +avgrtt=138 maxrtt=392 +*/ + diff --git a/test.h b/test.h new file mode 100644 index 0000000..1c40a9b --- /dev/null +++ b/test.h @@ -0,0 +1,241 @@ +#ifndef __TEST_H__ +#define __TEST_H__ + +#include +#include +#include +#include +#include + +#include "ikcp.h" + +#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64) +#include +#elif !defined(__unix) +#define __unix +#endif + +#ifdef __unix +#include +#include +#include +#include +#endif + +/* get system time */ +static inline void itimeofday(long *sec, long *usec) +{ + #if defined(__unix) + struct timeval time; + gettimeofday(&time, NULL); + if (sec) *sec = time.tv_sec; + if (usec) *usec = time.tv_usec; + #else + static long mode = 0, addsec = 0; + BOOL retval; + static IINT64 freq = 1; + IINT64 qpc; + if (mode == 0) { + retval = QueryPerformanceFrequency((LARGE_INTEGER*)&freq); + freq = (freq == 0)? 1 : freq; + retval = QueryPerformanceCounter((LARGE_INTEGER*)&qpc); + addsec = (long)time(NULL); + addsec = addsec - (long)((qpc / freq) & 0x7fffffff); + mode = 1; + } + retval = QueryPerformanceCounter((LARGE_INTEGER*)&qpc); + retval = retval * 2; + if (sec) *sec = (long)(qpc / freq) + addsec; + if (usec) *usec = (long)((qpc % freq) * 1000000 / freq); + #endif +} + +/* get clock in millisecond 64 */ +static inline IINT64 iclock64(void) +{ + long s, u; + IINT64 value; + itimeofday(&s, &u); + value = ((IINT64)s) * 1000 + (u / 1000); + return value; +} + +static inline IUINT32 iclock() +{ + return (IUINT32)(iclock64() & 0xfffffffful); +} + +/* sleep in millisecond */ +static inline void isleep(unsigned long millisecond) +{ + #ifdef __unix /* usleep( time * 1000 ); */ + struct timespec ts; + ts.tv_sec = (time_t)(millisecond / 1000); + ts.tv_nsec = (long)((millisecond % 1000) * 1000000); + /*nanosleep(&ts, NULL);*/ + usleep((millisecond << 10) - (millisecond << 4) - (millisecond << 3)); + #elif defined(_WIN32) + Sleep(millisecond); + #endif +} + +#ifdef __cplusplus +#include +#include + +// 带延迟的数据包 +class DelayPacket +{ +public: + virtual ~DelayPacket() { + if (_ptr) delete _ptr; + _ptr = NULL; + } + + DelayPacket(int size, const void *src = NULL) { + _ptr = new unsigned char[size]; + _size = size; + if (src) { + memcpy(_ptr, src, size); + } + } + + unsigned char* ptr() { return _ptr; } + const unsigned char* ptr() const { return _ptr; } + + int size() const { return _size; } + IUINT32 ts() const { return _ts; } + void setts(IUINT32 ts) { _ts = ts; } + +protected: + unsigned char *_ptr; + int _size; + IUINT32 _ts; +}; + +// 均匀分布的随机数 +class Random +{ +public: + Random(int size) { + this->size = 0; + seeds.resize(size); + } + + int random() { + int x, i; + if (seeds.size() == 0) return 0; + if (size == 0) { + for (i = 0; i < (int)seeds.size(); i++) { + seeds[i] = i; + } + size = (int)seeds.size(); + } + i = rand() % size; + x = seeds[i]; + seeds[i] = seeds[--size]; + return x; + } + +protected: + int size; + std::vector seeds; +}; + +// 网络延迟模拟器 +class LatencySimulator +{ +public: + virtual ~LatencySimulator() { + clear(); + } + + // lostrate: 往返一周丢包率的百分比，默认 10% + // rttmin：rtt最小值，默认 60 + // rttmax：rtt最大值，默认 125 + LatencySimulator(int lostrate = 10, int rttmin = 60, int rttmax = 125, int nmax = 1000): + r12(100), r21(100) { + current = iclock(); + this->lostrate = lostrate / 2; // 上面数据是往返丢包率，单程除以2 + this->rttmin = rttmin / 2; + this->rttmax = rttmax / 2; + this->nmax = nmax; + } + + // 清除数据 + void clear() { + DelayTunnel::iterator it; + for (it = p12.begin(); it != p12.end(); it++) { + delete *it; + } + for (it = p21.begin(); it != p21.end(); it++) { + delete *it; + } + p12.clear(); + p21.clear(); + } + + // 发送数据 + // peer - 端点0/1，从0发送，从1接收；从1发送从0接收 + void send(int peer, const void *data, int size) { + if (peer == 0) { + if (r12.random() < lostrate) return; + if ((int)p12.size() >= nmax) return; + } else { + if (r21.random() < lostrate) return; + if ((int)p21.size() >= nmax) return; + } + DelayPacket *pkt = new DelayPacket(size, data); + current = iclock(); + IUINT32 delay = rttmin; + if (rttmax > rttmin) delay += rand() % (rttmax - rttmin); + pkt->setts(current + delay); + if (peer == 0) { + p12.push_back(pkt); + } else { + p21.push_back(pkt); + } + } + + // 接收数据 + int recv(int peer, void *data, int maxsize) { + DelayTunnel::iterator it; + if (peer == 0) { + it = p21.begin(); + if (p21.size() == 0) return -1; + } else { + it = p12.begin(); + if (p12.size() == 0) return -1; + } + DelayPacket *pkt = *it; + current = iclock(); + if (current < pkt->ts()) return -2; + if (maxsize < pkt->size()) return -3; + if (peer == 0) { + p21.erase(it); + } else { + p12.erase(it); + } + maxsize = pkt->size(); + memcpy(data, pkt->ptr(), maxsize); + return maxsize; + } + +protected: + IUINT32 current; + int lostrate; + int rttmin; + int rttmax; + int nmax; + typedef std::list DelayTunnel; + DelayTunnel p12; + DelayTunnel p21; + Random r12; + Random r21; +}; + +#endif + +#endif + +