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C语言编写一个HTTP

发布时间:2010-05-08 12:54:44来源:红联作者:静静飞舞
服务器源代码如下:#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include



#define DEFAULTIP "127.0.0.1"

#define DEFAULTPORT "80"

#define DEFAULTBACK "10"

#define DEFAULTDIR "/home"

#define DEFAULTLOG "/tmp/das-server.log"



void prterrmsg(char *msg);

#define prterrmsg(msg) { perror(msg); abort(); }

void wrterrmsg(char *msg);

#define wrterrmsg(msg) { fputs(msg, logfp); fputs(strerror(errno), logfp);fflush(logfp); abort(); }



void prtinfomsg(char *msg);

#define prtinfomsg(msg) { fputs(msg, stdout); }

void wrtinfomsg(char *msg);

#define wrtinfomsg(msg) { fputs(msg, logfp); fflush(logfp);}



#define MAXBUF 1024



char buffer[MAXBUF + 1];

char *host = 0;

char *port = 0;

char *back = 0;

char *dirroot = 0;

char *logdir = 0;

unsigned char daemon_y_n = 0;

FILE *logfp;



#define MAXPATH 150



/*----------------------------------------

*--- dir_up - 查找dirpath所指目录的上一级目录

*----------------------------------------

*/

char *dir_up(char *dirpath)

{

static char Path[MAXPATH];

int len;



strcpy(Path, dirpath);

len = strlen(Path);

if (len > 1 && Path[len - 1] == '/')

len--;

while (Path[len - 1] != '/' && len > 1)

len--;

Path[len] = 0;

return Path;

}



/*------------------------------------------------------

*--- AllocateMemory - 分配空间并把d所指的内容复制

*------------------------------------------------------

*/

void AllocateMemory(char **s, int l, char *d)

{

*s = malloc(l + 1);

bzero(*s, l + 1);

memcpy(*s, d, l);

}

/************关于本文档********************************************

*filename: das-server.c

*purpose: 这是在Linux下用C语言写的目录访问服务器,支持目录浏览和文件下载

*wrote by: zhoulifa(zhoulifa@163.com) 周立发(http://zhoulifa.bokee.com)

Linux爱好者 Linux知识传播者 SOHO族 开发者 最擅长C语言

*date time:2007-01-26 19:32

*Note: 任何人可以任意复制代码并运用这些文档,当然包括你的商业用途

* 但请遵循GPL

*Thanks to: Google.com

*Hope:希望越来越多的人贡献自己的力量,为科学技术发展出力

* 科技站在巨人的肩膀上进步更快!感谢有开源前辈的贡献!

*********************************************************************/

/*------------------------------------------------------

*--- GiveResponse - 把Path所指的内容发送到client_sock去

*-------------------如果Path是一个目录,则列出目录内容

*-------------------如果Path是一个文件,则下载文件

*------------------------------------------------------

*/

void GiveResponse(FILE * client_sock, char *Path)

{

struct dirent *dirent;

struct stat info;

char Filename[MAXPATH];

DIR *dir;

int fd, len, ret;

char *p, *realPath, *realFilename, *nport;



/* 获得实际工作目录或文件 */

len = strlen(dirroot) + strlen(Path) + 1;

realPath = malloc(len + 1);

bzero(realPath, len + 1);

sprintf(realPath, "%s/%s", dirroot, Path);



/* 获得实际工作端口 */

len = strlen(port) + 1;

nport = malloc(len + 1);

bzero(nport, len + 1);

sprintf(nport, ":%s", port);



/* 获得实际工作目录或文件的信息以判断是文件还是目录 */

if (stat(realPath, &info)) {

fprintf(client_sock,

"HTTP/1.1 200 OK\r\nServer: DAS by ZhouLifa\r\nConnection: close\r\n\r\n%d - %s"

"Linux 下目录访问服务器


"

"", errno,

strerror(errno));

fprintf(client_sock,

"
请向管理员咨询为何出现如下错误提示:\n%s %s",

Path, strerror(errno));

goto out;

}

/* 处理浏览文件请求,即下载文件 */

if (S_ISREG(info.st_mode)) {

fd = open(realPath, O_RDONLY);

len = lseek(fd, 0, SEEK_END);

p = (char *) malloc(len + 1);

bzero(p, len + 1);

lseek(fd, 0, SEEK_SET);

ret = read(fd, p, len);

close(fd);

fprintf(client_sock,

"HTTP/1.1 200 OK\r\nServer: DAS by ZhouLifa\r\nConnection: keep-alive\r\nContent-type: application/*\r\nContent-Length:%d\r\n\r\n",

len);

fwrite(p, len, 1, client_sock);

free(p);

} else if (S_ISDIR(info.st_mode)) {

/* 处理浏览目录请求 */

dir = opendir(realPath);

fprintf(client_sock,

"HTTP/1.1 200 OK\r\nServer: DAS by ZhouLifa\r\nConnection: close\r\n\r\n%s"

"Linux 下目录访问服务器


"

"", Path);

fprintf(client_sock,

"\n",

Path);

fprintf(client_sock,

"\n");

if (dir == 0) {

fprintf(client_sock,

"
目录 %s
名称大小修改时间
%s",

strerror(errno));

return;

}

/* 读取目录里的所有内容 */

while ((dirent = readdir(dir)) != 0) {

if (strcmp(Path, "/") == 0)

sprintf(Filename, "/%s", dirent->d_name);

else

sprintf(Filename, "%s/%s", Path, dirent->d_name);

fprintf(client_sock, "");

len = strlen(dirroot) + strlen(Filename) + 1;

realFilename = malloc(len + 1);

bzero(realFilename, len + 1);

sprintf(realFilename, "%s/%s", dirroot, Filename);

if (stat(realFilename, &info) == 0) {

if (strcmp(dirent->d_name, "..") == 0)

fprintf(client_sock,

"(parent)",

host, atoi(port) == 80 ? "" : nport,

dir_up(Path));

else

fprintf(client_sock,

"%s",

host, atoi(port) == 80 ? "" : nport, Filename,

dirent->d_name);

if (S_ISDIR(info.st_mode))

fprintf(client_sock, "目录");

else if (S_ISREG(info.st_mode))

fprintf(client_sock, "%d", info.st_size);

else if (S_ISLNK(info.st_mode))

fprintf(client_sock, "链接");

else if (S_ISCHR(info.st_mode))

fprintf(client_sock, "字符设备");

else if (S_ISBLK(info.st_mode))

fprintf(client_sock, "块设备");

else if (S_ISFIFO(info.st_mode))

fprintf(client_sock, "FIFO");

else if (S_ISSOCK(info.st_mode))

fprintf(client_sock, "Socket");

else

fprintf(client_sock, "(未知)");

fprintf(client_sock, "%s", ctime(&info.st_ctime));

}

fprintf(client_sock, "\n");

free(realFilename);

}

fprintf(client_sock, "
");

} else {

/* 既非常规文件又非目录,禁止访问 */

fprintf(client_sock,

"HTTP/1.1 200 OK\r\nServer: DAS by ZhouLifa\r\nConnection: close\r\n\r\npermission denied"

"Linux 下目录访问服务器


"

"");

fprintf(client_sock,

"
你访问的资源'%s'被禁止访问,请联系管理员解决!",

Path);

}

out:

free(realPath);

free(nport);

}



/*------------------------------------------------------

*--- getoption - 分析取出程序的参数

*------------------------------------------------------

*/

void getoption(int argc, char **argv)

{

int c, len;

char *p = 0;



opterr = 0;

while (1) {

int option_index = 0;

static struct option long_options[] = {

{"host", 1, 0, 0},

{"port", 1, 0, 0},

{"back", 1, 0, 0},

{"dir", 1, 0, 0},

{"log", 1, 0, 0},

{"daemon", 0, 0, 0},

{0, 0, 0, 0}

};

/* 本程序支持如一些参数:

* --host IP地址 或者 -H IP地址

* --port 端口 或者 -P 端口

* --back 监听数量 或者 -B 监听数量

* --dir 网站根目录 或者 -D 网站根目录

* --log 日志存放路径 或者 -L 日志存放路径

* --daemon 使程序进入后台运行模式

*/

c = getopt_long(argc, argv, "H:P:B:D:L",

long_options, &option_index);

if (c == -1 || c == '?')

break;



if(optarg) len = strlen(optarg);

else len = 0;



if ((!c && !(strcasecmp(long_options[option_index].name, "host")))

|| c == 'H')

p = host = malloc(len + 1);

else if ((!c

&&

!(strcasecmp(long_options[option_index].name, "port")))

|| c == 'P')

p = port = malloc(len + 1);

else if ((!c

&&

!(strcasecmp(long_options[option_index].name, "back")))

|| c == 'B')

p = back = malloc(len + 1);

else if ((!c

&& !(strcasecmp(long_options[option_index].name, "dir")))

|| c == 'D')

p = dirroot = malloc(len + 1);

else if ((!c

&& !(strcasecmp(long_options[option_index].name, "log")))

|| c == 'L')

p = logdir = malloc(len + 1);

else if ((!c

&&

!(strcasecmp

(long_options[option_index].name, "daemon")))) {

daemon_y_n = 1;

continue;

}

else

break;

bzero(p, len + 1);

memcpy(p, optarg, len);

}

}



int main(int argc, char **argv)

{

struct sockaddr_in addr;

int sock_fd, addrlen;



/* 获得程序工作的参数,如 IP 、端口、监听数、网页根目录、目录存放位置等 */

getoption(argc, argv);



if (!host) {

addrlen = strlen(DEFAULTIP);

AllocateMemory(&host, addrlen, DEFAULTIP);

}

if (!port) {

addrlen = strlen(DEFAULTPORT);

AllocateMemory(&port, addrlen, DEFAULTPORT);

}

if (!back) {

addrlen = strlen(DEFAULTBACK);

AllocateMemory(&back, addrlen, DEFAULTBACK);

}

if (!dirroot) {

addrlen = strlen(DEFAULTDIR);

AllocateMemory(&dirroot, addrlen, DEFAULTDIR);

}

if (!logdir) {

addrlen = strlen(DEFAULTLOG);

AllocateMemory(&logdir, addrlen, DEFAULTLOG);

}



printf

("host=%s port=%s back=%s dirroot=%s logdir=%s %s是后台工作模式(进程ID:%d)\n",

host, port, back, dirroot, logdir, daemon_y_n?"":"不", getpid());



/* fork() 两次处于后台工作模式下 */

if (daemon_y_n) {

if (fork())

exit(0);

if (fork())

exit(0);

close(0), close(1), close(2);

logfp = fopen(logdir, "a+");

if (!logfp)

exit(0);

}



/* 处理子进程退出以免产生僵尸进程 */

signal(SIGCHLD, SIG_IGN);



/* 创建 socket */

if ((sock_fd = socket(PF_INET, SOCK_STREAM, 0)) < 0) {

if (!daemon_y_n) {

prterrmsg("socket()");

} else {

wrterrmsg("socket()");

}

}



/* 设置端口快速重用 */

addrlen = 1;

setsockopt(sock_fd, SOL_SOCKET, SO_REUSEADDR, &addrlen,

sizeof(addrlen));



addr.sin_family = AF_INET;

addr.sin_port = htons(atoi(port));

addr.sin_addr.s_addr = inet_addr(host);

addrlen = sizeof(struct sockaddr_in);

/* 绑定地址、端口等信息 */

if (bind(sock_fd, (struct sockaddr *) &addr, addrlen) < 0) {

if (!daemon_y_n) {

prterrmsg("bind()");

} else {

wrterrmsg("bind()");

}

}



/* 开启临听 */

if (listen(sock_fd, atoi(back)) < 0) {

if (!daemon_y_n) {

prterrmsg("listen()");

} else {

wrterrmsg("listen()");

}

}

while (1) {

int len;

int new_fd;

addrlen = sizeof(struct sockaddr_in);

/* 接受新连接请求 */

new_fd = accept(sock_fd, (struct sockaddr *) &addr, &addrlen);

if (new_fd < 0) {

if (!daemon_y_n) {

prterrmsg("accept()");

} else {

wrterrmsg("accept()");

}

break;

}

bzero(buffer, MAXBUF + 1);

sprintf(buffer, "连接来自于: %s:%d\n",

inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));

if (!daemon_y_n) {

prtinfomsg(buffer);

} else {

wrtinfomsg(buffer);

}

/* 产生一个子进程去处理请求,当前进程继续等待新的连接到来 */

if (!fork()) {

bzero(buffer, MAXBUF + 1);

if ((len = recv(new_fd, buffer, MAXBUF, 0)) > 0) {

FILE *ClientFP = fdopen(new_fd, "w");

if (ClientFP == NULL) {

if (!daemon_y_n) {

prterrmsg("fdopen()");

} else {

prterrmsg("fdopen()");

}

} else {

char Req[MAXPATH + 1] = "";

sscanf(buffer, "GET %s HTTP", Req);

bzero(buffer, MAXBUF + 1);

sprintf(buffer, "请求取文件: \"%s\"\n", Req);

if (!daemon_y_n) {

prtinfomsg(buffer);

} else {

wrtinfomsg(buffer);

}

/* 处理用户请求 */

GiveResponse(ClientFP, Req);

fclose(ClientFP);

}

}

exit(0);

}

close(new_fd);

}

close(sock_fd);

return 0;

}
复制代码编译程序用下列命令:
gcc -Wall das-server.c -o das-server
注:das即 Dictory Access Server

以root用户启动服务程序用下列命令:
./das-server
或以普通用户启动服务程序用下列命令:
./das-server --port 7838

./das-server -P 7838

注:只有root用户才有权限启动1024以下的端口,所以如果想用默认的80端口就得用root来运行。


转载于http://www.linuxdiyf.com/bbs/thread-34995-1-1.html
文章评论

共有 2 条评论

  1. 依尔杉思 于 2010-05-13 02:53:17发表:

    介么好滴话题,顶上去

  2. wei554807385 于 2010-05-08 14:49:58发表:

    能用么?
    :0wioe(1