C++怎么计算单个进程的网络负荷

在C++中计算单个进程的网络负荷可以使用系统调用和网络库进行实现。以下是一个示例代码，可以获取指定进程的网络连接信息和网络负载信息：

#include <iostream>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <netdb.h>
#include <ifaddrs.h>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <poll.h>
#include <cstring>
#include <cstdio>
#include <cstdlib>

using namespace std;

// 获取进程的TCP连接信息
bool get_tcp_info(int pid, vector<struct tcp_info> &tcp_infos) {
    FILE *fp = NULL;
    char filename[32] = {0};
    char linebuf[256] = {0};

    sprintf(filename, "/proc/%d/net/tcp", pid);
    fp = fopen(filename, "r");
    if (fp == NULL) {
        perror("open");
        return false;
    }

    while (fgets(linebuf, sizeof(linebuf), fp)) {
        struct tcp_info tcp_info;
        int index = 0;
        char *p = strtok(linebuf, " ");
        while (p != NULL) {
            if (index == 1) {
                sscanf(p, "%x:%x", &tcp_info.local_ip, &tcp_info.local_port);
            } else if (index == 2) {
                sscanf(p, "%x:%x", &tcp_info.remote_ip, &tcp_info.remote_port);
            } else if (index == 3) {
                sscanf(p, "%x", &tcp_info.status);
            }
            p = strtok(NULL, " ");
            index++;
        }
        tcp_infos.push_back(tcp_info);
    }

    fclose(fp);
    return true;
}

// 获取进程的UDP连接信息
bool get_udp_info(int pid, vector<struct udp_info> &udp_infos) {
    FILE *fp = NULL;
    char filename[32] = {0};
    char linebuf[256] = {0};

    sprintf(filename, "/proc/%d/net/udp", pid);
    fp = fopen(filename, "r");
    if (fp == NULL) {
        perror("open");
        return false;
    }

    while (fgets(linebuf, sizeof(linebuf), fp)) {
        struct udp_info udp_info;
        int index = 0;
        char *p = strtok(linebuf, " ");
        while (p != NULL) {
            if (index == 1) {
                sscanf(p, "%x:%x", &udp_info.local_ip, &udp_info.local_port);
            } else if (index == 2) {
                sscanf(p, "%x:%x", &udp_info.remote_ip, &udp_info.remote_port);
            }
            p = strtok(NULL, " ");
            index++;
        }
        udp_infos.push_back(udp_info);
    }

    fclose(fp);
    return true;
}

// 获取TCP连接的负载信息
bool get_tcp_load(int sockfd, struct tcp_load &load) {
    char buf[1024];
    int ret = recv(sockfd, buf, sizeof(buf), MSG_PEEK);
    if (ret == -1) {
        perror("recv");
        return false;
    } else {
        load.recv_bytes = ret;
    }

    ret = send(sockfd, buf, sizeof(buf), MSG_DONTWAIT);
    if (ret == -1) {
        perror("send");
        return false;
    } else {
        load.send_bytes = ret;
    }

    return true;
}

// 获取UDP连接的负载信息
bool get_udp_load(int sockfd, struct udp_load &load) {
    char buf[1024];
    struct sockaddr_in addr;
    socklen_t addrlen = sizeof(addr);

    int ret = recvfrom(sockfd, buf, sizeof(buf), MSG_PEEK, (struct sockaddr *) &addr, &addrlen);
    if (ret == -1) {
        perror("recvfrom");
        return false;
    } else {
        load.recv_bytes = ret;
    }

    ret = sendto(sockfd, buf, sizeof(buf), MSG_DONTWAIT, (struct sockaddr *) &addr, addrlen);
    if (ret == -1) {
        perror("sendto");
        return false;
    } else {
        load.send_bytes = ret;
    }

    return true;
}

int main(int argc, char **argv) {
    int pid = atoi(argv[1]);
    vector<struct tcp_info> tcp_infos;
    vector<struct udp_info> udp_infos;

    // 获取进程的TCP连接信息
    if (!get_tcp_info(pid, tcp_infos)) {
        return -1;
    }

    // 获取进程的UDP连接信息
    if (!get_udp_info(pid, udp_infos)) {
        return -1;
    }

    // 遍历TCP连接信息，获取负载信息
    for (auto tcp_info : tcp_infos) {
        int sockfd = socket(AF_INET, SOCK_STREAM, 0);
        if (sockfd == -1) {
            perror("socket");
            return -1;
        }

        struct sockaddr_in addr;
        memset(&addr, 0, sizeof(addr));
        addr.sin_family = AF_INET;
        addr.sin_port = htons(tcp_info.remote_port);
        addr.sin_addr.s_addr = htonl(tcp_info.remote_ip);

        if (connect(sockfd, (struct sockaddr *) &addr, sizeof(addr)) == -1) {
            perror("connect");
            return -1;
        }

        struct tcp_load load;
        if (get_tcp_load(sockfd, load)) {
            cout << "TCP " << inet_ntoa(*(struct in_addr *) &tcp_info.local_ip) << ":" << tcp_info.local_port << "->"
                 << inet_ntoa(*(struct in_addr *) &tcp_info.remote_ip) << ":" << tcp_info.remote_port << " SEND:"
                 << load.send_bytes << " RECV:" << load.recv_bytes << endl;
        }

        close(sockfd);
    }

    // 遍历UDP连接信息，获取负载信息
    for (auto udp_info : udp_infos) {
        int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
        if (sockfd == -1) {
            perror("socket");
            return -1;
        }

        struct sockaddr_in addr;
        memset(&addr, 0, sizeof(addr));
        addr.sin_family = AF_INET;
        addr.sin_port = htons(udp_info.remote_port);
        addr.sin_addr.s_addr = htonl(udp_info.remote_ip);

        struct udp_load load;
        if (get_udp_load(sockfd, load)) {
            cout << "UDP " << inet_ntoa(*(struct in_addr *) &udp_info.local_ip) << ":" << udp_info.local_port << "->"
                 << inet_ntoa(*(struct in_addr *) &udp_info.remote_ip) << ":" << udp_info.remote_port << " SEND:"
                 << load.send_bytes << " RECV:" << load.recv_bytes << endl;
        }

        close(sockfd);
    }

    return 0;
}

上述代码可以获取指定进程的TCP连接和UDP连接信息，并且可以遍历所有连接并获取连接的负载信息。具体实现方式需要根据具体的需求和环境来选择合适的方法。