给我一份c语言写的socket实现http请求的代码，不使用http库

下面是一个简单的C语言实现HTTP请求的代码，使用了socket库进行网络通信。代码中实现了GET和POST请求，并可以自定义请求头和请求体。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

#define HTTP_PORT 80

// 发送HTTP请求
int send_http_request(char *host, char *path, char *method, char *data, char *headers) {
    int sockfd, portno, n;
    struct sockaddr_in serv_addr;
    struct hostent *server;

    char buffer[1024];
    char request[2048];

    portno = HTTP_PORT;
    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0) {
        perror("ERROR opening socket");
        return -1;
    }

    server = gethostbyname(host);
    if (server == NULL) {
        fprintf(stderr, "ERROR, no such host\n");
        return -1;
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    bcopy((char *)server->h_addr, (char *)&serv_addr.sin_addr.s_addr, server->h_length);
    serv_addr.sin_port = htons(portno);

    if (connect(sockfd,(struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0) {
        perror("ERROR connecting");
        return -1;
    }

    if (strcmp(method, "GET") == 0) {
        sprintf(request, "GET %s HTTP/1.1\r\nHost: %s\r\n%s\r\n\r\n", path, host, headers);
    } else if (strcmp(method, "POST") == 0) {
        sprintf(request, "POST %s HTTP/1.1\r\nHost: %s\r\n%s\r\nContent-Length: %d\r\n\r\n%s", path, host, headers, strlen(data), data);
    } else {
        return -1;
    }

    n = write(sockfd, request, strlen(request));
    if (n < 0) {
        perror("ERROR writing to socket");
        return -1;
    }

    memset(buffer, 0, sizeof(buffer));
    while (read(sockfd, buffer, sizeof(buffer) - 1) > 0) {
        printf("%s", buffer);
        memset(buffer, 0, sizeof(buffer));
    }

    close(sockfd);
    return 0;
}

int main() {
    char *host = "www.example.com";
    char *path = "/";
    char *method = "GET";
    char *data = "";
    char *headers = "";

    send_http_request(host, path, method, data, headers);

    return 0;
}