[PHP] 通用网关接口CGI 的运行原理详解编程语言

#include <stdio.h> 
#include <stdlib.h> 
#include <signal.h> 
#include <unistd.h> 
#include <sys/types.h> 
#include <sys/socket.h> 
#include <arpa/inet.h> 
#include <netinet/in.h> 
#include <string.h> 
#define SERV_PORT 9003 
char *str_join(char *str1, char *str2); 
char *html_response(char *res, char *buf); 
int main(void) { 
int lfd, cfd; 
struct sockaddr_in serv_addr, clin_addr; 
socklen_t clin_len; 
char buf[1024], web_result[1024]; 
int len; 
FILE *cin; 
if ((lfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { 
perror("create socket failed"); 
exit(1); 
} 
memset(&serv_addr, 0, sizeof(serv_addr)); 
serv_addr.sin_family = AF_INET; 
serv_addr.sin_addr.s_addr = htonl(INADDR_ANY); 
serv_addr.sin_port = htons(SERV_PORT); 
if (bind(lfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) == -1) { 
perror("bind error"); 
exit(1); 
} 
if (listen(lfd, 128) == -1) { 
perror("listen error"); 
exit(1); 
} 
signal(SIGCLD, SIG_IGN); 
while (1) { 
clin_len = sizeof(clin_addr); 
if ((cfd = accept(lfd, (struct sockaddr *) &clin_addr, &clin_len)) == -1) { 
perror("接收错误/n"); 
continue; 
} 
cin = fdopen(cfd, "r"); 
setbuf(cin, (char *) 0); 
fgets(buf, 1024, cin); //读取第一行 
printf("/n%s", buf); 
//============================ cgi 环境变量设置演示 ============================ 
// 例如 "GET /cgi-bin/user?id=1 HTTP/1.1"; 
char *delim = " "; 
char *p; 
char *method, *filename, *query_string; 
char *query_string_pre = "QUERY_STRING="; 
method = strtok(buf, delim);         // GET 
p = strtok(NULL, delim);             // /user?id=1  
filename = strtok(p, "?");           // /user 
if (strcmp(filename, "/favicon.ico") == 0) { 
continue; 
} 
query_string = strtok(NULL, "?");    // id=1 
        putenv(str_join(query_string_pre, query_string)); 
//============================ cgi 环境变量设置演示 ============================ 
int pid = fork(); 
if (pid > 0) { 
close(cfd); 
} 
else if (pid == 0) { 
close(lfd); 
FILE *stream = popen(str_join(".", filename), "r"); 
fread(buf, sizeof(char), sizeof(buf), stream); 
html_response(web_result, buf); 
write(cfd, web_result, sizeof(web_result)); 
pclose(stream); 
close(cfd); 
exit(0); 
} 
else { 
perror("fork error"); 
exit(1); 
} 
} 
close(lfd); 
return 0; 
} 
char *str_join(char *str1, char *str2) { 
char *result = malloc(strlen(str1) + strlen(str2) + 1); 
if (result == NULL) exit(1); 
strcpy(result, str1); 
strcat(result, str2); 
return result; 
} 
char *html_response(char *res, char *buf) { 
char *html_response_template = "HTTP/1.1 200 OK/r/nContent-Type:text/html/r/nContent-Length: %d/r/nServer: mengkang/r/n/r/n%s"; 
sprintf(res, html_response_template, strlen(buf), buf); 
return res; 
}

#include <stdio.h> 
#include <stdlib.h> 
// 通过获取的 id 查询用户的信息 
int main(void) { 
//============================ 模拟数据库 ============================ 
typedef struct { 
int id; 
char *username; 
int age; 
} user; 
user users[] = { 
{}, 
{ 
1, 
"taoshihan", 
10 
} 
}; 
//============================ 模拟数据库 ============================ 
char *query_string; 
int id; 
query_string = getenv("QUERY_STRING"); 
if (query_string == NULL) { 
printf("没有输入数据"); 
} else if (sscanf(query_string, "id=%d", &id) != 1) { 
printf("没有输入id"); 
} else { 
printf("用户信息查询<br>学号: %d<br>姓名: %s<br>年龄: %d", id, users[id].username, users[id].age); 
} 
return 0; 
}