Extract Packet Fields from Byte Stream

Code

#include <stdio.h>
#include <stdint.h>

typedef struct {
    uint8_t start;
    uint8_t command;
    uint16_t data;
    uint8_t crc;
    uint8_t end;
} Packet;

void print_packet_fields(uint8_t *buffer) {
    // Overlay struct and print values
    Packet *s = (Packet *)buffer;
    /*s.start = buffer[0];
    s.command = buffer[1];
    s.data = s.data | buffer[2];
    s.data = s.data | (buffer[3] << 8);
    s.crc = buffer[4];
    s.end = buffer[5];*/

    printf("Start: %d\n",s->start);
    printf("Command: %d\n",s->command);
    printf("Data: %d\n",s->data);
    printf("CRC: %d\n",s->crc);
    printf("End: %d\n",s->end);
}

int main() {
    uint8_t buffer[6];
    for (int i = 0; i < 6; i++) {
        scanf("%hhu", &buffer[i]);
    }
    print_packet_fields(buffer);
    return 0;
}

Solving Approach

 

 

 

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Input

165 1 52 18 119 90

Expected Output

Start: 165 Command: 1 Data: 4660 CRC: 119 End: 90