/* *	This file is sdp parse source file, used to parse the packet of *	network and abstract the multimedia data * *	copyright (c) reserved 2008.09.09 */#include	"sdp.h"#include	<ctype.h>#include	<string.h>#include	<stdio.h>#include	<iostream>#include	<string>using	namespace	std;static	unsigned int basevalue(unsigned char base){	int		base64 = base;	if(islower(base64))	{		return base64 - 71;	}		if(isupper(base64))	{		return	base64 - 65;	}	if(isdigit(base64))	{		return	base64 + 4;	}	if(base64 == '+')	{		return	base64 + 19;	}	if(base64 == '/')	{		return	base64 + 16;	}		if(base64 =='=')	{		return	0;	}}int	base64decoder(char *result, char *src){	unsigned int	ch0 = 0, ch1;	char				buf[160], ch2; 	int				length, point = -1, pointer = 0;	length = strlen(src);	while(length > ++ point)	{		if(src[point] != '=')		{			ch0 = basevalue(src[point]); 			ch0 = ch0 << 18;		}		else		{			cout << "error!" << endl;			return	0;		}		if(src[++ point] != '=')		{			ch1 = basevalue(src[point]);			ch1 = ch1 << 12;			ch0 = ch0 | ch1;		}		else		{			cout << "error!" << endl;			return	0;		}		if(src[++ point] != '=')		{			ch1 = basevalue(src[point]);			ch1 = ch1 << 6;			ch0 = ch0 | ch1;		}		else		{			ch2 = (char)(ch0 >> 16);			result[pointer ++] = ch2;			break;		}		if(src[++ point] != '=')		{			ch1 = basevalue(src[point]);			ch0 = ch1 | ch0;		}		else		{			ch2 = (char)(ch0 >> 16);			result[pointer ++] = ch2;			ch2 = (char)(ch0 >> 8);			result[pointer ++] = ch2;			break;		}				ch2 = (char)(ch0 >> 16);		result[pointer ++] = ch2;		ch2 = (char)(ch0 >> 8);		result[pointer ++] = ch2;		ch2 = (char)ch0;		result[pointer ++] = ch2;	}	result[pointer] = '\0';	return	pointer;}static	int	filter(const char *in, const char *filter, char *out){	int		flen	= strlen(filter);	int		slen	= strlen(in);	if(!strncmp(in, filter, flen))	{		if(in[flen] == '"')			flen ++;		if(in[slen - 2] == '"')			slen -= 2;		memcpy(out, in + flen, slen - flen);		out[slen - flen] = '\0';		out[slen - flen] = '\0';		return	slen - flen;	}	return	0;}char	*strdup(char *buf){	if(buf != NULL)	{		int		len = strlen(buf);		char *data = new char[len + 1];		memcpy(data, buf, len);		data[len] = 0;		return	data;	}	return	NULL;}static	sdp_stream_t	*sdp_parse_m_symbol(char *data){	sdp_stream_t	*desc = new	sdp_stream_t;	char	buf[1024];	if(filter(data, "m=", buf))	{		desc -> id = strdup(buf);	}	else	{		cout << "sdp: no m= found." << endl;		delete	desc;		return	NULL;	}		return	desc;}static	int	sdp_parse_stream(sdp_stream_t *desc, FILE *rfile, char *buffer){	char	buf[1024], data[1024], *pdata;	char	decode[1024];	int		handled;	if(rfile != NULL && desc != NULL)	{		pdata = fgets(data, 1024, rfile);	}	else	{		cout << "parameters error." << endl;		return	-1;	}	while(pdata != NULL && data[0] != 'm')	{		handled = 0;		if(filter(pdata, "a=control:streamid=", buf))		{			desc -> stream_id = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=MaxBitRate:integer;", buf))		{			desc -> max_bit_rate = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=AvgBitRate:integer;", buf))		{			desc -> avg_bit_rate = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=MaxPacketSize:integer;", buf))		{			desc -> max_packet_size = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=AvgPacketSize:integer;", buf))		{			desc -> avg_packet_size = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=StartTime:integer;", buf)) 		{			desc -> start_time = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=Preroll:integer;", buf))		{			desc -> preroll = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=length:npt=", buf))		{			desc -> duration = (unsigned int)(atof(buf) * 1000);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=StreamName:string;", buf))		{			desc -> stream_name = strdup(buf);			desc -> stream_name_size = strlen(desc -> stream_name);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=mimetype:string;", buf))		{			desc -> mime_type = strdup(buf);			desc -> mime_type_size = strlen(desc -> mime_type);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=OpaqueData:buffer;", buf)) 		{			desc -> opaque_data_size = base64decoder(decode, buf);			desc -> opaque_data = new char[desc -> opaque_data_size];			memcpy(desc -> opaque_data, decode, desc -> opaque_data_size);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=ASMRuleBook:string;", buf))		{			desc -> asm_rule_book = strdup(buf);			desc -> asm_rule_book_length = strlen(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}				if(pdata[0] != 'm')		{			printf("sdp stream parse: not handled: %s", data);			pdata = fgets(data, 1024, rfile);			continue;		}		else		{			memcpy(buffer, data, strlen(data));			return	1;		}	}	if(data[0] == 'm')	{		return	1;	}	return	0;}sdp_t	*sdp_parse(FILE *rfile){	sdp_t	*desc = new sdp_t;	sdp_stream_t	*stream;	char	buf[1024], data[1024], *pdata;	char	decode[1024];	int		handled = 0;	int		len;	if(rfile == NULL)	{		return	NULL;	}	if((pdata = fgets(data, 1024, rfile)) == NULL)	{		return	NULL;	}	while(pdata != NULL)	{		handled = 0;		if(filter(pdata, "a=Title:buffer;", buf))		{			base64decoder(decode, buf);			desc -> title = strdup(decode);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=Author:buffer;", buf))		{			base64decoder(decode, buf);			desc -> author = strdup(decode);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=Copyright:buffer;", buf))		{			base64decoder(decode, buf);			desc -> copyright = strdup(decode);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=Abstract:buffer;", buf))		{			base64decoder(decode, buf);			desc -> abstract = strdup(decode);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=StreamCount:integer;", buf))		{			desc -> stream_count = atoi(buf);			desc -> stream  = new sdp_pstream_t[desc -> stream_count];			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(filter(pdata, "a=Flags:integer;", buf))		{			desc -> flags = atoi(buf);			handled = 1;			pdata = fgets(data, 1024, rfile);			continue;		}		if(!handled)		{			if(pdata[0] == 'm')			{				goto header;			}			printf("sdp: not found: %s", data);			pdata = fgets(data, 1024, rfile);			continue;		}	}	delete	desc;	return	NULL;header:	do	{		stream = sdp_parse_m_symbol(data);		if(stream != NULL)		{			len = sdp_parse_stream(stream, rfile, data);			desc -> stream[stream -> stream_id] = stream;		}		else		{			delete	desc;			return	NULL;		}	}while(len == 1);	return	desc;}//	need to definatively delete all the dynamic memoryvoid sdp_free(sdp_t *desc) {	if(desc == NULL)	{		return	;	}		if(desc -> owner)		delete	desc -> owner;	if(desc -> session_name)		delete	desc -> session_name;	if(desc -> uri)		delete	desc -> uri;	if(desc -> email)		delete	desc -> email;	if(desc -> phone)		delete 	desc -> phone;	if(desc -> connection)		delete	desc -> connection;	if(desc -> bandwidth)		delete	desc -> bandwidth;	if(desc -> title)		delete	desc -> title;	if(desc -> author)		delete	desc -> author;	if(desc -> copyright)		delete	desc -> copyright;	if(desc -> keywords)		delete	desc -> keywords;	if(desc -> asm_rule_book)		delete	desc -> asm_rule_book;	if(desc -> abstract)		delete	desc -> abstract;	if(desc -> stream)	{		int	i = 0;		while(desc -> stream[i])		{			if(desc -> stream[i] -> id)				delete	desc -> stream[i] -> id;			if(desc -> stream[i] -> bandwidth)				delete	desc -> stream[i] -> bandwidth;			if(desc -> stream[i] -> range)				delete	desc -> stream[i] -> range;			if(desc -> stream[i] -> length)				delete	desc -> stream[i] -> length;			if(desc -> stream[i] -> rtpmap)				delete	desc -> stream[i] -> rtpmap;			if(desc -> stream[i] -> mimetype)				delete	desc -> stream[i] -> mimetype;			if(desc -> stream[i] -> stream_name)				delete	desc -> stream[i] -> stream_name;			if(desc -> stream[i] -> mime_type)				delete	desc -> stream[i] -> mime_type;			if(desc -> stream[i] -> opaque_data)				delete	desc -> stream[i] -> opaque_data;			if(desc -> stream[i] -> rmff_flags)				delete	desc -> stream[i] -> rmff_flags;						delete	desc -> stream[i];			++ i;		}		delete	desc -> stream;	}  	delete	desc;}