Commit 223addb1 authored by Andreas Schmidt's avatar Andreas Schmidt
Browse files

Packet copies are now shallow copies by default

parent fff6c3e9

prrt/CMakeLists.txt

+2 −0
Original line number Diff line number Diff line
@@ -16,6 +16,8 @@ add_subdirectory(util) 


add_executable(sender sender.c)

add_executable(receiver receiver.c)

add_executable(refcount refcount.c)



target_link_libraries(sender LINK_PUBLIC PRRT UTIL ${CMAKE_THREAD_LIBS_INIT})

target_link_libraries(receiver LINK_PUBLIC PRRT UTIL ${CMAKE_THREAD_LIBS_INIT})

target_link_libraries(refcount LINK_PUBLIC PRRT UTIL ${CMAKE_THREAD_LIBS_INIT})

prrt/proto/types/packet.c

+22 −4
Original line number Diff line number Diff line
@@ -92,6 +92,11 @@ int PrrtPacket_print(PrrtPacket *packet_ptr) { 
}



PrrtPacket *PrrtPacket_copy(PrrtPacket *original) {

    __sync_fetch_and_add(&original->refcount, 1);

    return original;

}



PrrtPacket *PrrtPacket_deepcopy(PrrtPacket *original) {

    PrrtPacket *newPacket = calloc(1, sizeof(PrrtPacket));

    check_mem(newPacket);

    void *payload = calloc(1, original->payloadLength);
@@ -105,6 +110,8 @@ PrrtPacket *PrrtPacket_copy(PrrtPacket *original) { 
    newPacket->sequenceNumber = original->sequenceNumber;

    newPacket->type_priority = original->type_priority;



    newPacket->refcount = 1;





    return newPacket;

    error:
@@ -122,6 +129,7 @@ create_header(uint8_t priority, prrtSequenceNumber_t seqno, prrtPacketLength_t s 
    packet->index = index;

    packet->sequenceNumber = seqno;

    packet->payloadLength = size;

    packet->refcount = 1;



    return packet;
@@ -214,6 +222,10 @@ void *encode_general_header(void *buf_ptr, const PrrtPacket *packet) { 
}



bool PrrtPacket_decode(void *srcBuffer, uint16_t srcBufferSize, PrrtPacket *targetPacket) {



    // targetPacket is uninitialized, so we need to set the reference count

    targetPacket->refcount = 1;



    prrtPacketLength_t payload_len = (prrtPacketLength_t) (srcBufferSize - PRRT_PACKET_ENCODED_GENERAL_HEADER_LENGTH);

    targetPacket->type_priority = *(uint8_t *) srcBuffer;

    srcBuffer += 1;
@@ -295,12 +307,18 @@ void *decode_data_header(void *dstBuffer, const void *srcBuffer) { 
}



int PrrtPacket_destroy(PrrtPacket *packet) {



    prrtRefcount_t refcount = __sync_fetch_and_sub(&packet->refcount, 1);

    if (refcount > 1) {

        return 0;

    } else {

        if (packet->payload != NULL) {

            free(packet->payload);

        }

        free(packet);

        return 0;

    }

}



PrrtPacket *PrrtPacket_create_data_packet(uint8_t priority, const void *payloadPointer,

                                          prrtPacketLength_t dataLength, prrtSequenceNumber_t sequenceNumber,

prrt/proto/types/packet.h

+6 −0
Original line number Diff line number Diff line
@@ -36,6 +36,8 @@ typedef atomic_uint_fast32_t prrtAtomicDeliveryRate_t; 
typedef uint32_t prrtByteCount_t;

typedef uint8_t prrtPacketType_t;



typedef uint16_t prrtRefcount_t;



typedef struct prrtIncompleteBlock {

    prrtSequenceNumber_t sequenceNumberBase;

    uint16_t repairCycleIndex;
@@ -58,6 +60,8 @@ typedef struct prrtPacket { 
    prrtTimedelta_t rtt;



    struct sockaddr_in sender_addr;



    prrtRefcount_t refcount;

} PrrtPacket;

#define PRRT_PACKET_GENERAL_HEADER_SIZE 8

#define PRRT_PACKET_ENCODED_GENERAL_HEADER_LENGTH 4
@@ -124,6 +128,8 @@ int PrrtPacket_print(PrrtPacket *packet_ptr); 


PrrtPacket *PrrtPacket_copy(PrrtPacket *original);



PrrtPacket *PrrtPacket_deepcopy(PrrtPacket *original);



PrrtPacket *PrrtPacket_create_data_packet(uint8_t priority, const void *payloadPointer,

                                          prrtPacketLength_t dataLength, prrtSequenceNumber_t sequenceNumber,

                                          prrtTimedelta_t targetDelay);

prrt/refcount.c

0 → 100644
+19 −0
Original line number Diff line number Diff line 
#include "proto/types/packet.h"

#include <stdio.h>

#include <stdlib.h>

#include <string.h>



const int prio = 0;

const int seqnum = 1337;

const int timedelta = 0;



int main() {

    const char* payload = "just some example payload";

    struct prrtPacket *a = PrrtPacket_create_data_packet(prio, payload, strlen(payload), seqnum, timedelta);

    printf("refcount(a): %u\n\n", a->refcount);

    struct prrtPacket *b = PrrtPacket_copy(a);

    printf("refcount(a): %u\nrefcount(b): %u\n\n", a->refcount, b->refcount);

    PrrtPacket_destroy(a);

    printf("refcount(b): %u\n", b->refcount);

    PrrtPacket_destroy(b);

}