我正在尝试创建一个 C 服务器，它将接受输入并能够通过 html 格式将它们返回给用户，其中服务器充当用户界面。我当前的问题似乎无法弄清楚为什么 C 服务器在 localhost:3838 处将 HTML 代码以文本形式吐出，而不是将其显示为正确的网页。
我该如何解决这个问题并让它能够将用户命令发送回服务器并发出正确的响应？我是否使用以下方法来做到这一点recieve然后将消息放入缓冲区，解析该消息，然后将该响应放入缓冲区以使用send?
CSERVER.c
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>
#define PORT "3838" //port being connected to
#define MAXLEN 800
#define BACKLOG 10 //number of pending connections to be held in queue
//format of html page
char header []=
"<!DOCTYPE html>\n"
"<html>\n"
"<head>\n"
"<title>Web-Based Remote Command Server</title>\n"
"</head>\n"
"<body>\n\n";
char input []=
"<form action= \"/run\" method= \"get\"> \n"
"Command: <input type=\"text\" size=\"100\" name=\"command\">\n"
"<input type=\"submit\" value=\"Run\">\n"
"</form>";
char output []= "<p>Command that was run:</p>\n"
"<pre>Your server will include the command that was just run here.</pre>\n\n"
"<p>Standard Output:</p>\n""<pre>Your server will include the stdout results here.</pre>\n\n"
"<p>Standard Error:</p>\n"
"<pre>Your server will include the stderr results here.</pre>\n\n"
"</body>\n""</html>";
char *buff = header;
void sigchld_handler(int s)
{
(void)s; // quiet unused variable warning
// waitpid() might overwrite errno, so we save and restore it:
int saved_errno = errno;
while(waitpid(-1, NULL, WNOHANG) > 0);
errno = saved_errno;
}
void *get_in_addr(struct sockaddr *sa)
{
if (sa->sa_family == AF_INET) {
return &(((struct sockaddr_in*)sa)->sin_addr);
}
return &(((struct sockaddr_in6*)sa)->sin6_addr);
}
int main (void){
int sockfd;
int new_fd;
struct addrinfo hints;
struct addrinfo *serverinfo;
struct addrinfo *p;
struct sockaddr_storage client_addr;
socklen_t addrsize;
struct sigaction sa;
int yes = 1;
char s[INET6_ADDRSTRLEN];
int status;
memset(&hints, 0, sizeof hints); //makes struct empty
hints.ai_family = AF_UNSPEC; //IPv4 or v6
hints.ai_socktype = SOCK_STREAM; //TCP type need
hints.ai_flags = AI_PASSIVE; //Fill in IP for us
//if can't get address info print error
if((status = getaddrinfo(NULL, PORT, &hints, &serverinfo)) != 0){
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(status));
return 1;
}
for(p = serverinfo; p != NULL; p = p->ai_next){
if((sockfd = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1){
perror("server: socket");
continue;
}
if(setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1){
perror("setsockopt");
exit(1);
}
if(bind(sockfd, p->ai_addr, p->ai_addrlen) == -1){
close(sockfd);
perror("server: bind");
continue;
}
break;
}
freeaddrinfo(serverinfo);
if(p == NULL){
fprintf(stderr, "server: failed to bind\n");
exit(1);
}
if(listen(sockfd, BACKLOG) == -1){
perror("listen");
exit(1);
}
sa.sa_handler = sigchld_handler; // reap all dead processes
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
if (sigaction(SIGCHLD, &sa, NULL) == -1) {
perror("sigaction");
exit(1);
}
printf("server: waiting for connections....\n");
while(1){
addrsize = sizeof client_addr;
new_fd = accept(sockfd, (struct sockaddr *)&client_addr, &addrsize);
if(new_fd == -1){
perror("Did not accept");
continue;
}
inet_ntop(client_addr.ss_family, get_in_addr((struct sockaddr *)&client_addr), s, sizeof s);
printf("server: got connection from %s\n", s);
if(!fork()){
close(sockfd);
int bufsize = 1024;
char *buffer = malloc(bufsize);
recv(new_fd, buffer, bufsize, 0);
write(new_fd, "HTTP/1.1 200 OK\n", 16);
write(new_fd, "Content-length: 46\n", 19);
write(new_fd, "Content-type: text/html\n\n", 25);
write(new_fd, "<html><head>\n<title>The Web Page</title>\n</head>\n</html>", 46);
if(send(new_fd, header, MAXLEN, 0) == -1)
perror("send");
close(new_fd);
exit(0);
}
close(new_fd);
}
return 0;
}
