Commit 1f4889cc authored by Andreas Schmidt's avatar Andreas Schmidt
Browse files

Refactor forward packet table to make use of bitmap.

parent 0441ee3e

CMakeLists.txt

+3 −1
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ set(CMAKE_CXX_FLAGS_RELEASE "-Os -Wall" ) 
enable_testing()



find_package (Threads)

find_library(M_LIB m)





include_directories(${CMAKE_CURRENT_SOURCE_DIR})

src/prrt/packet.h

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ typedef struct prrtPacket { 
#define PRRT_PACKET_GENERAL_HEADER_SIZE 8

#define PRRT_PACKET_ENCODED_GENERAL_HEADER_LENGTH 4



#define SEQNO_SPACE 65536 // 2**16 as seqno is uint16_t

#define SEQNO_SPACE UINT16_MAX // 2**16 as seqno is uint16_t



typedef struct prrtPacketDataPayload {

    uint32_t timestamp;

src/prrt/stores/forward_packet_table.c

+8 −15
Original line number Diff line number Diff line 
#include <stdint.h>

#include <string.h>

#include "../../defines.h"

#include "../packet.h"

#include "forward_packet_table.h"
@@ -12,37 +11,34 @@ int is_position_relevant(const PrrtForwardPacketTable *fpt_ptr, uint16_t seqno) 
    } else if (!(seqno <= stop || fpt_ptr->start <= seqno)) {

        return false;

    } else {

        uint16_t which_byte = (uint16_t) (seqno / 32);

        uint16_t which_bit = (uint16_t) (seqno % 32);

        return ((fpt_ptr->data[which_byte] >> which_bit) & 0x01) == 0;

        return Bitmap_get(fpt_ptr->bitmap, seqno);

    }

}



void move_start(PrrtForwardPacketTable *fpt_ptr) {

    uint16_t seqno = fpt_ptr->start;

    uint16_t which_byte;

    uint16_t which_bit;



    while(1) {

        which_byte = (uint16_t) (seqno / 32);

        which_bit = (uint16_t) (seqno % 32);

        if (((fpt_ptr->data[which_byte] >> which_bit ) & 0x01) == 0) {

        if (Bitmap_get(fpt_ptr->bitmap, seqno)) {

            break;

        }

        fpt_ptr->data[which_byte] &= ~(1 << which_bit);

        Bitmap_set(fpt_ptr->bitmap, seqno, true);

        seqno++;

    }



    // TODO: make more efficient by using the Bitmap_set_range function



    fpt_ptr->start = seqno;

}



int PrrtForwardPacketTable_create(PrrtForwardPacketTable *fpt_prt) {

    fpt_prt->start = 1;

    memset(fpt_prt->data, 0, sizeof(fpt_prt->data));

    fpt_prt->bitmap = Bitmap_create(true, SEQNO_SPACE);

    return EXIT_SUCCESS;

}



bool PrrtForwardPacketTable_destroy(PrrtForwardPacketTable* fpt_prt) {

    Bitmap_destroy(fpt_prt->bitmap);

    free(fpt_prt);

    return true;

}
@@ -51,10 +47,7 @@ int PrrtForwardPacketTable_test_set_is_number_relevant(PrrtForwardPacketTable *f 
    int res = is_position_relevant(fpt_ptr, seqno);



    if(res) {

        uint16_t which_byte = (uint16_t) (seqno / 32);

        uint16_t which_bit = (uint16_t) (seqno % 32);

        fpt_ptr->data[which_byte] |= 1 << which_bit;



        Bitmap_set(fpt_ptr->bitmap, seqno, false);

        if(seqno == fpt_ptr->start) {

            move_start(fpt_ptr);

        }

src/prrt/stores/forward_packet_table.h

+2 −4
Original line number Diff line number Diff line
@@ -3,13 +3,11 @@ 


#include <stdint.h>

#include <stdbool.h>



#define FORWARD_PACKET_TABLE_LENGTH 2048  // sequence number space is 2**16 and we have 32 bit so: 2048

#include "../../util/bitmap.h"



typedef struct {

    uint32_t data[FORWARD_PACKET_TABLE_LENGTH];

    uint16_t start;



    Bitmap* bitmap;

} PrrtForwardPacketTable;



int PrrtForwardPacketTable_create(PrrtForwardPacketTable* fpt_prt);

src/util/CMakeLists.txt

+1 −0
Original line number Diff line number Diff line 
add_library(UTIL ../defines.h common.c common.h list.c list.h dbg.h bptree.c bptree.h bitmap.c bitmap.h)

set_property(TARGET UTIL PROPERTY C_STANDARD 99)

target_link_libraries(UTIL ${M_LIB})
 
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