protohackersc/server02.c

//
// Created by Ajurna on 28/07/2025.
//

#include "server02.h"
#include <winsock2.h>
#include <stdio.h>
#include "data.h"
#include <pthread.h>

int main() {
    SOCKET server = get_listen_socket();
    SOCKADDR_IN clientAddr;
    SOCKET client;
    int clientAddrSize = sizeof(clientAddr);
    int connection_number = 1;
    printf("Listening for incoming connections...\n");
    while((client = accept(server, (SOCKADDR *)&clientAddr, &clientAddrSize)) != INVALID_SOCKET)
    {
        handle_args_t *args = malloc(sizeof(handle_args_t));
        args->client = client;
        args->connection = connection_number++;
        pthread_t thread;
        pthread_create(&thread, nullptr, handle_connection, args);
    }
    return 0;
}
void *handle_connection(void *args) {
    handle_args_t *handleArgs = args;
    char buffer[1024] = {0};
    int bytesReceived;
    char_array_t *data = char_array_create(1024);
    price_array_t *prices = price_array_create(1024);
    while ((bytesReceived = recv(handleArgs->client, buffer, sizeof(buffer), 0)) > 0) {
        printf("Client sent {%d}: |%d| \n", handleArgs->connection, bytesReceived);
        char_array_append(data, buffer, bytesReceived);
        query_or_insert_t *request;
        while ((request = fix_message(char_array_get_bytes(data, 9))) != NULL) {
            //parse_request(handleArgs, request, data);
            switch (request->insert.type) {
                case INSERT:
                    printf("{%d} timestamp: %d, price: %d\n", handleArgs->connection, request->insert.timestamp, request->insert.price);
                    price_array_append(prices, &request->insert);
                    break;
                case QUERY:
                    printf("{%d} Query min: %d, max: %d\n", handleArgs->connection, request->query.mintime, request->query.maxtime);
                    int average = price_array_query(prices, &request->query);
                    printf("{%d} Query min: %d, max: %d avg %d\n", handleArgs->connection, request->query.mintime, request->query.maxtime, average);
                    int32_t response = htonl(average);
                    send(handleArgs->client, (char*)&response, sizeof(response), 0);
                default:
                    closesocket(handleArgs->client);
                    free(handleArgs);
                    pthread_exit(NULL);
                    exit(3);
            }
            // free(request);
        }
        memset(buffer, 0, sizeof(buffer));
    }

    closesocket(handleArgs->client);
    free(handleArgs);
    pthread_exit(NULL);
}

query_or_insert_t *fix_message(char *message) {
    if (message == NULL) {
        return NULL;
    }
    query_or_insert_t *ret = malloc(sizeof(query_or_insert_t));
    ret->insert.type = message[0];
    ret->query.mintime = message[4] | (message[3] << 8) | (message[2] << 16) | (message[1] << 24);
    ret->query.maxtime = message[8] | (message[7] << 8) | (message[6] << 16) | (message[5] << 24);
    return ret;
}

price_array_t *price_array_create(int capacity) {
    price_array_t *array = malloc(sizeof(price_array_t));
    array->capacity = capacity;
    array->size = 0;
    array->data = calloc(capacity, sizeof(price_t));
    return array;
};
void price_array_free(price_array_t *array) {
    free(array->data);
    free(array);
};
void price_array_append(price_array_t *array, insert_t *value) {
    if (array->data == NULL) {
        exit(1);
    }
    size_t new_size = array->size + 1;
    if (new_size > array->capacity) {
        array->capacity = array->capacity+1024;
        price_t *new_array = realloc(array->data, array->capacity);
        array->data = new_array;
        if (array->data == NULL) {
            printf("Failed to allocate memory for array\n");
            exit(1);
        }
    }
    price_t *temp = malloc(sizeof(price_t));
    temp->timestamp = value->timestamp;
    temp->price = value->price;
    array->data[array->size] = *temp;
    array->size = new_size;
};
int price_array_query(price_array_t *array, query_t *query) {

    int count = 0;
    int total = 0;
    for (int i = 0; i < array->size; i++) {
        if (array->data[i].timestamp >= query->mintime && array->data[i].timestamp <= query->maxtime) {
            count++;
            total += array->data[i].price;
        }
    }
    printf("{%d} Found %d prices\n", query->mintime, count);
    int ret;
    if (count == 0) {
        ret = 0;
    } else {
        ret = total/count;
    }
    return ret;
};