diff options
Diffstat (limited to 'metis/ccnx/forwarder/metis/core/metis_Wldr.c')
| -rw-r--r-- | metis/ccnx/forwarder/metis/core/metis_Wldr.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/metis/ccnx/forwarder/metis/core/metis_Wldr.c b/metis/ccnx/forwarder/metis/core/metis_Wldr.c new file mode 100644 index 00000000..6249bf0a --- /dev/null +++ b/metis/ccnx/forwarder/metis/core/metis_Wldr.c @@ -0,0 +1,174 @@ +/* + * Copyright (c) 2017 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + + +#include <stdint.h> +#include <stdio.h> +#include <ccnx/forwarder/metis/core/metis_Connection.h> +#include <ccnx/forwarder/metis/core/metis_Wldr.h> +#include <ccnx/forwarder/metis/core/metis_Forwarder.h> +#include <parc/logging/parc_LogReporterTextStdout.h> + +struct metis_wldr_buffer { + MetisMessage *message; + uint8_t rtx_counter; +}; + +typedef struct metis_wldr_buffer MetisWldrBuffer; + +struct metis_wldr_state { + uint16_t expected_label; + uint16_t next_label; + MetisWldrBuffer *buffer[BUFFER_SIZE]; +}; + +MetisWldr * +metisWldr_Init() +{ + MetisWldr *wldr = parcMemory_AllocateAndClear(sizeof(MetisWldr)); + assertNotNull(wldr, "parcMemory_AllocateAndClear(%zu) returned NULL", sizeof(MetisWldr)); + wldr->expected_label = 1; + wldr->next_label = 1; + for (int i = 0; i < BUFFER_SIZE; i++) { + MetisWldrBuffer *entry = parcMemory_AllocateAndClear(sizeof(MetisWldrBuffer)); + assertNotNull(entry, "WldrBuffer init: parcMemory_AllocateAndClear(%zu) returned NULL", sizeof(MetisWldrBuffer)); + entry->message = NULL; + entry->rtx_counter = 0; + wldr->buffer[i] = entry; + } + return wldr; +} + +void +metisWldr_ResetState(MetisWldr *wldr) +{ + wldr->expected_label = 1; + wldr->next_label = 1; + for (int i = 0; i < BUFFER_SIZE; i++) { + wldr->buffer[i]->message = NULL; + wldr->buffer[i]->rtx_counter = 0; + } +} + +void +metisWldr_Destroy(MetisWldr **wldrPtr) +{ + MetisWldr *wldr = *wldrPtr; + for (unsigned i = 0; i < BUFFER_SIZE; i++) { + if (wldr->buffer[i]->message != NULL) { + metisMessage_Release(&(wldr->buffer[i]->message)); + parcMemory_Deallocate((void **) &(wldr->buffer[i])); + } + } + parcMemory_Deallocate((void **) &wldr); + *wldrPtr = NULL; +} + + +static void +_metisWldr_RetransmitPacket(MetisWldr *wldr, const MetisConnection *conn, uint16_t label) +{ + if (wldr->buffer[label % BUFFER_SIZE]->message == NULL) { + printf("the required message for retransmission is not in the buffer\n"); + return; + } + + if (wldr->buffer[label % BUFFER_SIZE]->rtx_counter < MAX_RTX) { + MetisMessage *msg = wldr->buffer[label % BUFFER_SIZE]->message; + + //printf("-----retransmit packet label = %d, new label = %d\n", label, wldr->next_label); + metisMessage_SetWldrLabel(msg, wldr->next_label); + + if (wldr->buffer[wldr->next_label % BUFFER_SIZE]->message != NULL) { + //printf("-------------release message in retransmit packet, %d %d\n",(wldr->next_label % BUFFER_SIZE),wldr->next_label); + metisMessage_Release(&(wldr->buffer[wldr->next_label % BUFFER_SIZE]->message)); + } + + wldr->buffer[wldr->next_label % BUFFER_SIZE]->message = msg; + wldr->buffer[wldr->next_label % BUFFER_SIZE]->rtx_counter = wldr->buffer[label % BUFFER_SIZE]->rtx_counter + 1; + metisMessage_Acquire(wldr->buffer[wldr->next_label % BUFFER_SIZE]->message); + wldr->next_label++; + metisConnection_ReSend(conn, msg); + } +} + +static void +_metisWldr_SendWldrNotificaiton(MetisWldr *wldr, const MetisConnection *conn, MetisMessage *message, uint16_t expected_lbl, uint16_t received_lbl) +{ + //here we create a copy of the last message received and we use it as a loss notification + //this can be made more efficient using a pre-encoded message with a small size + MetisMessage *notification = metisMessage_Slice(message, 0, metisMessage_Length(message), 0, NULL); + metisMessage_SetWldrNotification(notification, expected_lbl, received_lbl); + //printf("------------send notification %u, %u\n",expected_lbl, received_lbl); + assertNotNull(notification, "Got null from Slice"); + metisConnection_ReSend(conn, notification); +} + + +void +metisWldr_SetLabel(MetisWldr *wldr, MetisMessage *message) +{ + //we send the packet for the first time + metisMessage_SetWldrLabel(message, wldr->next_label); + if (wldr->buffer[wldr->next_label % BUFFER_SIZE]->message != NULL) { + //printf("-------------release message in set label packet, %d %d\n",(wldr->next_label % BUFFER_SIZE),wldr->next_label); + metisMessage_Release(&(wldr->buffer[wldr->next_label % BUFFER_SIZE]->message)); + } + metisMessage_Acquire(message); + wldr->buffer[wldr->next_label % BUFFER_SIZE]->message = message; + wldr->buffer[wldr->next_label % BUFFER_SIZE]->rtx_counter = 0; + wldr->next_label++; +} + +void +metisWldr_DetectLosses(MetisWldr *wldr, const MetisConnection *conn, MetisMessage *message) +{ + if (metisMessage_HasWldr(message)) { + uint8_t wldr_type = (uint8_t) metisMessage_GetWldrType(message); + if (wldr_type == WLDR_LBL) { + uint16_t pkt_lbl = (uint16_t) metisMessage_GetWldrLabel(message); + //printf("--------------received packet label %u\n", pkt_lbl); + if (pkt_lbl != wldr->expected_label) { + //if the received packet label is 1 and the expected packet label > pkt_lbl + //usually we are in the case where a remove note disconnected for a while + //and reconnected on this same connection, so the two nodes are out of synch + //for this reason we do not send any notification, we just synch the labels + + if ((pkt_lbl != 1) || (wldr->expected_label < pkt_lbl)) { + _metisWldr_SendWldrNotificaiton(wldr, conn, message, wldr->expected_label, pkt_lbl); + } + + //here we always synch + wldr->expected_label = (uint16_t) (pkt_lbl + 1); + } else { + wldr->expected_label++; + } + } else if (wldr_type == WLDR_NOTIFICATION) { + uint16_t expected_lbl = (uint16_t) metisMessage_GetWldrLabel(message); + uint16_t received_lbl = (uint16_t) metisMessage_GetWldrLastReceived(message); + //printf("------------received notification %u, %u\n",expected_lbl, received_lbl); + if ((wldr->next_label - expected_lbl) > BUFFER_SIZE) { + //printf("--------------the packets are not in the buffer anymore %u %u %u\n", wldr->next_label, + // expected_lbl, BUFFER_SIZE); + //the packets are not in the buffer anymore + return; + } + while (expected_lbl < received_lbl) { + _metisWldr_RetransmitPacket(wldr, conn, expected_lbl); + expected_lbl++; + } + } + } +} |