Files
MIT6.828_OS/lab/lab6.si4project/Backup/httpd(174).c
2019-07-17 16:08:06 +08:00

328 lines
5.7 KiB
C

#include <inc/lib.h>
#include <lwip/sockets.h>
#include <lwip/inet.h>
#define PORT 80
#define VERSION "0.1"
#define HTTP_VERSION "1.0"
#define E_BAD_REQ 1000
#define BUFFSIZE 512
#define MAXPENDING 5 // Max connection requests
struct http_request {
int sock;
char *url;
char *version;
};
struct responce_header {
int code;
char *header;
};
struct responce_header headers[] = {
{ 200, "HTTP/" HTTP_VERSION " 200 OK\r\n"
"Server: jhttpd/" VERSION "\r\n"},
{0, 0},
};
struct error_messages {
int code;
char *msg;
};
struct error_messages errors[] = {
{400, "Bad Request"},
{404, "Not Found"},
};
static void
die(char *m)
{
cprintf("%s\n", m);
exit();
}
static void
req_free(struct http_request *req)
{
free(req->url);
free(req->version);
}
static int
send_header(struct http_request *req, int code)
{
struct responce_header *h = headers;
while (h->code != 0 && h->header!= 0) {
if (h->code == code)
break;
h++;
}
if (h->code == 0)
return -1;
int len = strlen(h->header);
if (write(req->sock, h->header, len) != len) {
die("Failed to send bytes to client");
}
return 0;
}
static int
send_data(struct http_request *req, int fd)
{
// LAB 6: Your code here.
panic("send_data not implemented");
}
static int
send_size(struct http_request *req, off_t size)
{
char buf[64];
int r;
r = snprintf(buf, 64, "Content-Length: %ld\r\n", (long)size);
if (r > 63)
panic("buffer too small!");
if (write(req->sock, buf, r) != r)
return -1;
return 0;
}
static const char*
mime_type(const char *file)
{
//TODO: for now only a single mime type
return "text/html";
}
static int
send_content_type(struct http_request *req)
{
char buf[128];
int r;
const char *type;
type = mime_type(req->url);
if (!type)
return -1;
r = snprintf(buf, 128, "Content-Type: %s\r\n", type);
if (r > 127)
panic("buffer too small!");
if (write(req->sock, buf, r) != r)
return -1;
return 0;
}
static int
send_header_fin(struct http_request *req)
{
const char *fin = "\r\n";
int fin_len = strlen(fin);
if (write(req->sock, fin, fin_len) != fin_len)
return -1;
return 0;
}
// given a request, this function creates a struct http_request
static int
http_request_parse(struct http_request *req, char *request)
{
const char *url;
const char *version;
int url_len, version_len;
if (!req)
return -1;
if (strncmp(request, "GET ", 4) != 0)
return -E_BAD_REQ;
// skip GET
request += 4;
// get the url
url = request;
while (*request && *request != ' ')
request++;
url_len = request - url;
req->url = malloc(url_len + 1);
memmove(req->url, url, url_len);
req->url[url_len] = '\0';
// skip space
request++;
version = request;
while (*request && *request != '\n')
request++;
version_len = request - version;
req->version = malloc(version_len + 1);
memmove(req->version, version, version_len);
req->version[version_len] = '\0';
// no entity parsing
return 0;
}
static int
send_error(struct http_request *req, int code)
{
char buf[512];
int r;
struct error_messages *e = errors;
while (e->code != 0 && e->msg != 0) {
if (e->code == code)
break;
e++;
}
if (e->code == 0)
return -1;
r = snprintf(buf, 512, "HTTP/" HTTP_VERSION" %d %s\r\n"
"Server: jhttpd/" VERSION "\r\n"
"Connection: close"
"Content-type: text/html\r\n"
"\r\n"
"<html><body><p>%d - %s</p></body></html>\r\n",
e->code, e->msg, e->code, e->msg);
if (write(req->sock, buf, r) != r)
return -1;
return 0;
}
static int
send_file(struct http_request *req)
{
int r;
off_t file_size = -1;
int fd;
// open the requested url for reading
// if the file does not exist, send a 404 error using send_error
// if the file is a directory, send a 404 error using send_error
// set file_size to the size of the file
// LAB 6: Your code here.
panic("send_file not implemented");
if ((r = send_header(req, 200)) < 0)
goto end;
if ((r = send_size(req, file_size)) < 0)
goto end;
if ((r = send_content_type(req)) < 0)
goto end;
if ((r = send_header_fin(req)) < 0)
goto end;
r = send_data(req, fd);
end:
close(fd);
return r;
}
static void
handle_client(int sock)
{
struct http_request con_d;
int r;
char buffer[BUFFSIZE];
int received = -1;
struct http_request *req = &con_d;
while (1)
{
// Receive message
if ((received = read(sock, buffer, BUFFSIZE)) < 0)
panic("failed to read");
memset(req, 0, sizeof(*req));
req->sock = sock;
r = http_request_parse(req, buffer);
if (r == -E_BAD_REQ)
send_error(req, 400);
else if (r < 0)
panic("parse failed");
else
send_file(req);
req_free(req);
// no keep alive
break;
}
close(sock);
}
void
umain(int argc, char **argv)
{
int serversock, clientsock;
struct sockaddr_in server, client;
binaryname = "jhttpd";
// Create the TCP socket
if ((serversock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
die("Failed to create socket");
// Construct the server sockaddr_in structure
memset(&server, 0, sizeof(server)); // Clear struct
server.sin_family = AF_INET; // Internet/IP
server.sin_addr.s_addr = htonl(INADDR_ANY); // IP address
server.sin_port = htons(PORT); // server port
// Bind the server socket
if (bind(serversock, (struct sockaddr *) &server,
sizeof(server)) < 0)
{
die("Failed to bind the server socket");
}
// Listen on the server socket
if (listen(serversock, MAXPENDING) < 0)
die("Failed to listen on server socket");
cprintf("Waiting for http connections...\n");
while (1) {
unsigned int clientlen = sizeof(client);
// Wait for client connection
if ((clientsock = accept(serversock,
(struct sockaddr *) &client,
&clientlen)) < 0)
{
die("Failed to accept client connection");
}
handle_client(clientsock);
}
close(serversock);
}