简单http_server的C语言实现

主要实现以下几点：

1.静态文件访问，包括jpg、html、css等

2.文件不存在404

3.目录列表

4.501 Not Implemented

=============================================================================

启动脚本

#!/bin/sh

ps -ef | grep fasthttp | grep -v grep | awk '{print $2}' | xargs -t -i kill -9 {} >/dev/null
gcc   fasthttp.c -o fasthttp
$(pwd)/fasthttp

以下是源码

=====================================================================================

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <error.h>
#include <errno.h>

#include <sys/types.h>
#include <dirent.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>

// 建立socket 开始侦听 接收连接 接收客户端数据 解析http协议 发送文件数据给客户端

#define HTTP_PORT "2010"
#define MAX_CONNECTION 10
#define DOCUMENT_ROOT "www"
#define LOG_PATH "log/access.log"

void parser(char *s,char res[][255],char host[][255]);
static char *strtoupper( char *s );
static long filesize(const char *filename);
static int file_exists(const char *filename);
static void mime_content_type( const char *name, char *ret );
static int WriteLog( const char *message );
static int is_dir(const char *filename);

static unsigned short g_is_log        = 1;
static int g_log_fd                    = 0;

int main(void)
{
    int server_sock;
    int client_sock;
    struct sockaddr_in server_addr;
    struct sockaddr_in client_addr;
    struct sockaddr_in sin;
    struct stat file_stat;
    pid_t pid;
    char client_ip[100];
    char buf[20000];
    char buf_all[2000];
    char buf1[2000];
    char p[3][255];
    char h[3][255];
    char tmp[2000];
    char cwd[1024];
    char filename[2000];
    char filepath[2000];
    int fd,size;
    int currentConn = 0;
    
    DIR * dir;
    struct dirent * ptr;
    


    chdir("../");
    
    if ( (pid = fork()) < 0 )
    {
        perror("fork");
        exit(1);
    }
    else if ( pid != 0)
    {
        exit(1);
    }
    
    if((server_sock = socket(AF_INET,SOCK_STREAM,0)) < 0)
    {
        perror("socket");
        exit(1);
    }
    
    memset(&server_addr,0,sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(atoi(HTTP_PORT));
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    
    if(bind(server_sock,(struct sockaddr*)&server_addr,sizeof(server_addr)) < 0)
    {
        perror("bind");
        exit(1);
    }
    
    if(listen(server_sock,MAX_CONNECTION) < 0)
    {
        perror("listen");
        exit(1);
    }
    
    printf("fasthttp successful created ...\n");
    
    while(1)
    {
        unsigned int clientlen = sizeof(client_addr);
        if((client_sock = accept(server_sock,(struct sockaddr*)&client_addr,&clientlen)) < 0)
        {
            perror("accept");
            exit(1);
        }
        
        if((pid = fork()) == 0)
        {

            if(read(client_sock,buf,20000) < 0)
            {
                perror("read data from client");
                exit(1);
            }
            
            parser(buf,p,h);
            
            if(strcmp(strtoupper(p[0]),"GET") != 0
                && strcmp(strtoupper(p[0]),"POST") != 0
                && strcmp(strtoupper(p[0]),"HEAD") != 0)
            {
                memset(&buf,0,sizeof(buf));
                
                sprintf(buf, "HTTP/1.1 501 Not Implemented\r\nServer: %s\r\nContent-Type: text/html\r\nContent-Length:    1489\r\nAccept-Ranges: bytes\r\nConnection: close\r\n\r\n", "Apache");
                write(client_sock,buf,strlen(buf));
                
                memset(&buf,0,sizeof(buf));
                sprintf(buf,"<h2>%s Method Not Implemented</h2>","501");
                write(client_sock,buf,strlen(buf));
                close(client_sock);
                exit(0);
            }
             
            if(strcmp(p[1],"/") == 0)
            {
                memset(&tmp,0,sizeof(tmp));
                sprintf(tmp,"%s","index.html");
                strcat(p[1],tmp);
            }
            
            WriteLog(p[1]);
            getcwd(filepath, sizeof(filepath));
            strcat(filepath,"/");
            strcat(filepath,DOCUMENT_ROOT);
             strcat(filepath,p[1]);

            if(!file_exists(filepath))
            {
                memset(&buf,0,sizeof(buf));
                sprintf(buf, "HTTP/1.1 404 Not Found\r\nServer: %s\r\nContent-Type: text/html\r\nContent-Length:    257271\r\nConnection: close\r\n\r\n", "Apache");
                write(client_sock,buf,strlen(buf));
                
                memset(&buf,0,sizeof(buf));
                sprintf(buf,"<html><head><title>404 Not Found</title></head><body bgcolor=\"white\"><center><h1>404 Not Found</h1></center><hr><center>Powered by %s</center></body></html>","fasthttp");
                write(client_sock,buf,strlen(buf));
                close(client_sock);
                
                memset(&buf,0,sizeof(buf));
                sprintf(buf,"404 Not Found\t%s\n",filepath);
                WriteLog(buf);
                
                exit(0);
            }
            
            if(access(filepath,R_OK) < 0)
            {
                memset(&buf,0,sizeof(buf));
                sprintf(buf, "HTTP/1.1 403 Forbidden\r\nServer: %s\r\nContent-Type: text/html\r\nContent-Length:    25727\r\nConnection: close\r\n\r\n", "Apache");
                write(client_sock,buf,strlen(buf));
                close(client_sock);
                exit(0);
            }
            
             /** 目录列表 **/
             if(is_dir(filepath))
             {
                memset(&tmp,0,sizeof(tmp));
                sprintf(tmp,"<html><head><title>Index of %s</title></head><body><h1>Index of %s</h1><ul><li><a href=\"/\"> Parent Directory</a></li>",filepath,filepath);
                strcat(buf,tmp);

                 if((dir = opendir(filepath)) != NULL)
                 {
                     while((ptr = readdir(dir)) != NULL)
                     {
                         
                         if(strcmp(ptr->d_name,".") == 0 || strcmp(ptr->d_name,"..") == 0)
                         {
                             continue;    
                         }
                         
                         memset(&buf,0,sizeof(buf));
                         sprintf(buf,"%s/%s",filepath,ptr->d_name);
                        
                        if(is_dir(buf))
                        {
                            memset(&buf,0,sizeof(buf));
                            sprintf(buf,"<li><a href=\"%s/\"> %s/</a></li>",ptr->d_name,ptr->d_name);
                        }
                        else
                        {
                            memset(&buf,0,sizeof(buf));
                            sprintf(buf,"<li><a href=\"%s\"> %s</a></li>",ptr->d_name,ptr->d_name);    
                        }
                        strcat(tmp,buf);
                     }
                 }
                 closedir(dir);

                 memset(&buf,0,sizeof(buf));
                sprintf(buf,"%s","</ul>");
                strcat(tmp,buf);
                
                memset(&buf,0,sizeof(buf));
                sprintf(buf, "HTTP/1.1 200 OK\r\nServer: fasthttp\r\nContent-Type: text/html;charset=utf-8\r\nContent-Length:    %d\r\nConnection: close\r\n\r\n", strlen(tmp));
                write(client_sock,buf,strlen(buf));
            
                write(client_sock,tmp,strlen(tmp));
                close(client_sock);
             }
             
            memset(&tmp,0,sizeof(tmp));
            mime_content_type(filepath,tmp);
            
            memset(&buf,0,sizeof(buf));
            sprintf(buf, "HTTP/1.1 200 OK\r\nServer: %s\r\nContent-Type: %s\r\nContent-Length:    25727\r\nConnection: close\r\n\r\n", "Apache",tmp);
            write(client_sock,buf,strlen(buf));
            
            
            
            memset(&buf,0,sizeof(buf));
            fd = open(filepath,O_RDONLY);
            read(fd,buf,filesize(filepath));
            close(fd);
            
            write(client_sock,buf,filesize(filepath));
            close(client_sock);
            
            memset(&buf,0,sizeof(buf));
            sprintf(buf,"200 OK\t%s\t%d\n",filepath,filesize(filepath));
            WriteLog(buf);
            
            exit(0);
        }
        else
        {
            wait(NULL);
        }
        
        close(client_sock);
    }
    
    
}

void parser(char *s,char res[][255],char host[][255])
{
    int i,j = 0;
    int n;
    char hosts[255];

    for (i = 0;s[i] != '\r';i++)        /* obtain the first line in http protocol head */
        ;
    s[i] = '\0';
    n=i++;
    
    for (i = 0,j = 0;i < 3;i++,j++)        /* divide the protocol head in blank */
    {
        strcpy(res[j],strsep(&s," "));
    }
    
    for(i=n;s[i] != '\r';i++)
    {
        strcat(hosts,s[i]);
    }
    
    for (i = 0,j = 0;i < 3;i++,j++)        /* divide the protocol head in blank */
    {
        strcpy(host[j],strsep(&hosts,":"));
    }
    
}

/**
 * strtoupper - string to upper
 *
 */
static char *strtoupper( char *s )
{
    int i, len = sizeof(s);
    for( i = 0; i < len; i++ )
    {
        s[i] = ( s[i] >= 'a' && s[i] <= 'z' ? s[i] + 'A' - 'a' : s[i] );
    }
    
    return(s);
}

/**
 *  filesize - get file size
 */
static long filesize(const char *filename)
{
    struct stat buf;
    if (!stat(filename, &buf))
    {
        return buf.st_size;
    }
    return 0;
}

/**
 * file_exists - check file is exist
 */
static int file_exists(const char *filename)
{
    struct stat buf;
    
    if (stat(filename, &buf) < 0)
    {
        if (errno == ENOENT)
        {
            return 0;
        }
    }
    return 1;
}

/**
 * Get MIME type header
 *
 */
static void mime_content_type( const char *name, char *ret ){
    char *dot, *buf;

    dot = strrchr(name, '.');

    /* Text */
    if ( strcmp(dot, ".txt") == 0 ){
        buf = "text/plain";
    } else if ( strcmp( dot, ".css" ) == 0 ){
        buf = "text/css";
    } else if ( strcmp( dot, ".js" ) == 0 ){
        buf = "text/javascript";
    } else if ( strcmp(dot, ".xml") == 0 || strcmp(dot, ".xsl") == 0 ){
        buf = "text/xml";
    } else if ( strcmp(dot, ".xhtm") == 0 || strcmp(dot, ".xhtml") == 0 || strcmp(dot, ".xht") == 0 ){
        buf = "application/xhtml+xml";
    } else if ( strcmp(dot, ".html") == 0 || strcmp(dot, ".htm") == 0 || strcmp(dot, ".shtml") == 0 || strcmp(dot, ".hts") == 0 ){
        buf = "text/html";

    /* Images */
    } else if ( strcmp( dot, ".gif" ) == 0 ){
        buf = "image/gif";
    } else if ( strcmp( dot, ".png" ) == 0 ){
        buf = "image/png";
    } else if ( strcmp( dot, ".bmp" ) == 0 ){
        buf = "application/x-MS-bmp";
    } else if ( strcmp( dot, ".jpg" ) == 0 || strcmp( dot, ".jpeg" ) == 0 || strcmp( dot, ".jpe" ) == 0 || strcmp( dot, ".jpz" ) == 0 ){
        buf = "image/jpeg";

    /* Audio & Video */
    } else if ( strcmp( dot, ".wav" ) == 0 ){
        buf = "audio/wav";
    } else if ( strcmp( dot, ".wma" ) == 0 ){
        buf = "audio/x-ms-wma";
    } else if ( strcmp( dot, ".wmv" ) == 0 ){
        buf = "audio/x-ms-wmv";
    } else if ( strcmp( dot, ".au" ) == 0 || strcmp( dot, ".snd" ) == 0 ){
        buf = "audio/basic";
    } else if ( strcmp( dot, ".midi" ) == 0 || strcmp( dot, ".mid" ) == 0 ){
        buf = "audio/midi";
    } else if ( strcmp( dot, ".mp3" ) == 0 || strcmp( dot, ".mp2" ) == 0 ){
        buf = "audio/x-mpeg";
    } else if ( strcmp( dot, ".rm" ) == 0  || strcmp( dot, ".rmvb" ) == 0 || strcmp( dot, ".rmm" ) == 0 ){
        buf = "audio/x-pn-realaudio";
    } else if ( strcmp( dot, ".avi" ) == 0 ){
        buf = "video/x-msvideo";
    } else if ( strcmp( dot, ".3gp" ) == 0 ){
        buf = "video/3gpp";
    } else if ( strcmp( dot, ".mov" ) == 0 ){
        buf = "video/quicktime";
    } else if ( strcmp( dot, ".wmx" ) == 0 ){
        buf = "video/x-ms-wmx";
    } else if ( strcmp( dot, ".asf" ) == 0  || strcmp( dot, ".asx" ) == 0 ){
        buf = "video/x-ms-asf";
    } else if ( strcmp( dot, ".mp4" ) == 0 || strcmp( dot, ".mpg4" ) == 0 ){
        buf = "video/mp4";
    } else if ( strcmp( dot, ".mpe" ) == 0  || strcmp( dot, ".mpeg" ) == 0 || strcmp( dot, ".mpg" ) == 0 || strcmp( dot, ".mpga" ) == 0 ){
        buf = "video/mpeg";

    /* Documents */
    } else if ( strcmp( dot, ".pdf" ) == 0 ){
        buf = "application/pdf";
    } else if ( strcmp( dot, ".rtf" ) == 0 ){
        buf = "application/rtf";
    } else if ( strcmp( dot, ".doc" ) == 0  || strcmp( dot, ".dot" ) == 0 ){
        buf = "application/msword";
    } else if ( strcmp( dot, ".xls" ) == 0  || strcmp( dot, ".xla" ) == 0 ){
        buf = "application/msexcel";
    } else if ( strcmp( dot, ".hlp" ) == 0  || strcmp( dot, ".chm" ) == 0 ){
        buf = "application/mshelp";
    } else if ( strcmp( dot, ".swf" ) == 0  || strcmp( dot, ".swfl" ) == 0 || strcmp( dot, ".cab" ) == 0 ){
        buf = "application/x-shockwave-flash";
    } else if ( strcmp( dot, ".ppt" ) == 0  || strcmp( dot, ".ppz" ) == 0 || strcmp( dot, ".pps" ) == 0 || strcmp( dot, ".pot" ) == 0 ){
        buf = "application/mspowerpoint";

    /* Binary & Packages */
    } else if ( strcmp( dot, ".zip" ) == 0 ){
        buf = "application/zip";
    } else if ( strcmp( dot, ".rar" ) == 0 ){
        buf = "application/x-rar-compressed";
    } else if ( strcmp( dot, ".gz" ) == 0 ){
        buf = "application/x-gzip";
    } else if ( strcmp( dot, ".jar" ) == 0 ){
        buf = "application/java-archive";
    } else if ( strcmp( dot, ".tgz" ) == 0  || strcmp( dot, ".tar" ) == 0 ){
        buf = "application/x-tar";
    } else {
        buf = "application/octet-stream";
    }
    strcpy(ret, buf);
}

/**
 * Log message
 *
 */
static int WriteLog( const char *message )
{
    if ( !g_is_log )
    {
        fprintf(stderr, "%s", message);
        return 0;
    }
    if ( g_log_fd == 0 )
    {
        char g_log_path[2000];
        getcwd(g_log_path, sizeof(g_log_path));
        strcat(g_log_path,"/");
        strcat(g_log_path,LOG_PATH);
        
        if ( (g_log_fd = open(g_log_path, O_RDWR|O_CREAT|O_APPEND, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)) == -1 )
        {
            perror("open log file error");
            return -1;
        }
    }
    
    if (write(g_log_fd, message, strlen(message)) == -1)
    {
        perror("write log error");
        return -1;
    }

    return 0;
}

/**
 * is_dir - check file is directory
 *
 */
static int is_dir(const char *filename){
    struct stat buf;
    if ( stat(filename, &buf) < 0 ){
        return -1;
    }
    if (S_ISDIR(buf.st_mode)){
        return 1;
    }
    return 0;
}