network.c

linux下流媒体下载程序代码

/***********************************************************************
 *    network.c: network related utility functions
 ***********************************************************************
 * Copyright (C) 2007 metro <[e-mail]>
 *
 * This file is part of msdl, media stream downloader
 *
 * network-unrelated functions goes to msdllib.c
 *
 * struct stream_t is a stream describer, and 
 * stream_ctrl is stream controller, actually works as a
 * network buffer and wrapper for all supported protocols.
 * 
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *
 ***********************************************************************/ 



#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <errno.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/select.h>

#include <netdb.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>

#include "msdl.h"
#include "msdllib.h"
#include "display.h"
#include "network.h"


/*
 * setup stream_t
 */
struct stream_t *new_stream_t(void)
{
    struct stream_t *st = (struct stream_t *)xmalloc(sizeof(struct stream_t));
    return st;
}



/*
 * free stream_t
 */
void free_stream_t(struct stream_t *st)
{
    if(!st) return;
    
    free(st);
}


struct stream_t *streaming_init_common()
{
    struct stream_t *stream = new_stream_t();
    
    stream->serverinfo = new_serverinfo_t();
    stream->netsock = new_netsock_t();
    stream->stream_ctrl = new_stream_ctrl_t();
    stream->resumeinfo = new_resumeinfo_t();

    return stream;
}


void streaming_close_common(struct stream_t *stream)
{
    free(stream->localfile);
    free_resumeinfo_t(stream->resumeinfo);
    free_stream_ctrl_t(stream->stream_ctrl);
    free_netsock_t(stream->netsock);
    free_serverinfo_t(stream->serverinfo);
    free_stream_t(stream);
}


/*
 * setup buffer, setup URL.
 */
struct stream_ctrl_t *new_stream_ctrl_t(void)
{
  
    struct stream_ctrl_t *sc =
	(struct stream_ctrl_t *)xmalloc(sizeof(struct stream_ctrl_t));

    sc->write_buffer = xmalloc(BUF_SIZE);
    sc->write_buffer_size = BUF_SIZE;
    
    return sc;
}



struct serverinfo_t *new_serverinfo_t(void)
{
    struct serverinfo_t *si = 
	(struct serverinfo_t *)xmalloc(sizeof(struct serverinfo_t));

    return si;
}


void free_serverinfo_t(struct serverinfo_t *si)
{
    if(!si) return;

    si->connect_host = NULL;
    if(si->host)       free(si->host);
    if(si->proxy_host) free(si->proxy_host);
    free(si);
}



struct netsock_t *new_netsock_t(void)
{
    struct netsock_t *ns = 
	(struct netsock_t *)xmalloc(sizeof(struct netsock_t));
    ns->buffer = xmalloc(BUF_SIZE);
    ns->buffer_size = BUF_SIZE;
    
    return ns;
}


void free_netsock_t(struct netsock_t *ns)
{
    if(!ns) return;

    if(ns->buffer) free(ns->buffer);
    free(ns);
}


struct resumeinfo_t *new_resumeinfo_t(void)
{
    struct resumeinfo_t *ri =
	(struct resumeinfo_t *)xmalloc(sizeof(struct resumeinfo_t));
    ri->resume_req_success  = 0;
    ri->resume_start_offset = 0;

    return ri;
}


void free_resumeinfo_t(struct resumeinfo_t *ri)
{
    free(ri);
}



/*
 * free stream_ctrl;
 */
void free_stream_ctrl_t(struct stream_ctrl_t *sc)
{
    if(!sc) return;
    
    /* if(sc->url) free_url_t(sc->url); not malloc()ed in new_stream_ctrl_t,
       thus, free this outside free_stream_ctrl_t().*/
    if(sc->write_buffer) free(sc->write_buffer);
    if(sc->retry_urlstr)   free(sc->retry_urlstr);

    free(sc);
}



/*
 * set server information
 */
void set_serverinfo(struct serverinfo_t *serverinfo,
		    char *target_host,int target_port,
		    char *proxy_host,int proxy_port,int protocol_default_port)
{
    if(!serverinfo) {
	display(MSDL_ERR,"set_serverinfo: argument NULL\n");
	return;
    }
    
    serverinfo->host = strdup(target_host);
    serverinfo->port = (target_port) ? target_port : protocol_default_port;
    
    serverinfo->connect_host = serverinfo->host;
    serverinfo->connect_port = serverinfo->port;

    if(proxy_host) {
	serverinfo->proxy_host = strdup(proxy_host);
	serverinfo->proxy_port = proxy_port;

	serverinfo->connect_host = serverinfo->proxy_host; /* reset host to connect() */
	serverinfo->connect_port = serverinfo->proxy_port; /* reset port to connect() */
    }
    else {
	serverinfo->proxy_host = NULL;
	serverinfo->proxy_port = 0;
    }
}



void set_serverinfo_by_proxy_string(struct serverinfo_t *serverinfo,
				    char *host,int port,char *proxy_string,
				    int protocol_default_port,int proxy_default_port)
{
    char *proxy_str = NULL;
    int proxy_port = 0;

    if(proxy_string) {
	char *port_str = NULL;
	proxy_str = strdup(proxy_string);
	port_str = strchr(proxy_str,':');
	
	if(!port_str) {
	    display(MSDL_NOR,"proxy port not specified, assuming %d\n",proxy_default_port);
	    proxy_port = proxy_default_port;
	}
	else {
	    *port_str = '\0';/* separate proxy_str*/
	    port_str++;
	    proxy_port = atoi(port_str);
	    if(!proxy_port) {
		proxy_port = proxy_default_port;
	    }
	}
    }
    
    set_serverinfo(serverinfo,host,port,proxy_str,proxy_port,protocol_default_port);
    
    if(proxy_str) free(proxy_str);
}



/*
 * return true if Speed string was valid
 * return value ... 1: valid   0: not valid
 *   reason_ret ... "": no error   some string: error reason
 */
int speed_valid_and_guess(const char *str,int *guessed_speed,char **reason_ret)
{
    /* 1*DIGIT [ "." *DIGIT ] */
    int i = 0;
    int len = strlen(str);
    int speed_valid = 1;
    char *reason = NULL;
    int value = 0;

    value = 0;
    speed_valid = 1;
    for(i = 0 ; i < len ; i++) {
	if('0' <= str[i] && str[i] <= '9') {
	    value *= 10;
	    value += str[i] - '0';
	    continue;
	}
	else if(str[i] == '.') {
	    if(i == 0) {
		reason = "\'.\' at the beginning of speed string";
		speed_valid = 0;
		break;
	    }
	    i++;
	    for(; i < len ; i++) {
		if(('0' <= str[i]) && (str[i] <= '9')) {
		    continue;
		}
		else {
		    reason = "invalid char after \'.\'";
		    speed_valid = 0;
		    break;
		}
	    }
	}
	else {
	    reason = "invalid character";
	    speed_valid = 0;
	    break;
	}
    }
    if(speed_valid) {
	reason = "";
	if(reason_ret) {
	    *reason_ret = reason;
	}
	/* do not care about guessed_speed */
	return speed_valid;
    }

    /* invalid */
    if(guessed_speed) {
	*guessed_speed = value;
    }
    if(reason_ret) {
	*reason_ret = reason;
    }
    return 0;
}



char *make_byterange_from_filesize(uint64_t filesize)
{
    char *rangestr = (char *)xmalloc(256);
    snprintf(rangestr,255,"%llu-",(long long unsigned int)filesize);
    return rangestr;
}



/*
 * (url_t)->protocol_type.
 * sets UNKNONW_PROTOCOL if protocol string not supported.
 */
int protocol_type_from_string(char *protocol)
{
    int protocol_type = UNKNOWN_PROTOCOL;
    
    if(!strcasecmp(protocol,"mms") || 
       !strcasecmp(protocol,"mmst")) {
	protocol_type = MMST;
    }
    else if(!strcasecmp(protocol,"mmsh")) {
	protocol_type = MMSH;
    }
    else if(!strcasecmp(protocol,"http")) {
	protocol_type = HTTP;
    }
    else if(!strcasecmp(protocol,"rtsp")) {
	protocol_type = RTSP;
    }
    else if(!strcasecmp(protocol,"ftp")) {
	protocol_type = FTP;
    }
    else {
	protocol_type = UNKNOWN_PROTOCOL;
    }
  
    return protocol_type;
}



/*
 * connect to 'servername' with 'port'.
 *           return value :    socket number ... success
 *                             -1            ... error
 */
int server_connect(const char *servername,const int port)
{
    
    int sock_server = 0;
    int ret;
    
    char hoststr[INET6_ADDRSTRLEN + 4]; /* IPv4 / IPv6 dual */
    char portstr[8];
    fd_set set;
    struct addrinfo hints,*result = NULL;
    
    struct timeval tv;    
    int try_count = 0;
    

    if(!servername) {
	goto failed;
    }
    
    if(0 <= port && port <= 0xffff) { /* valid params  */
	snprintf(portstr,7,"%d",port);
    }
    else {
	display(MSDL_ERR,"port number %d not valid",port);
	goto failed;
    }
    
    memset(&hints,0,sizeof(struct addrinfo));
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;
    
    ret = getaddrinfo(servername,portstr,&hints,&result);
    if(ret != 0) {
	display(MSDL_ERR,"Host [ %s ] not found. (%s)\n",servername,gai_strerror(ret));
	goto failed;
    }
    

    if(result->ai_family == AF_INET6) {
	inet_ntop(result->ai_family,
		  &((struct sockaddr_in6 *)result->ai_addr)->sin6_addr,
		  hoststr,
		  sizeof(hoststr));