Source code of Windows XP (NT5)
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/*
Copyright (c) 1997-1999 Microsoft Corporation
Module Name:
sdp.cpp
Abstract:
Author:
*/
#include "sdppch.h"
#include <strstrea.h>
#include "sdp.h"
#include "sdpstran.h"
// state transitions for each of the states
const STATE_TRANSITION g_StateStartTransitions[] = {
{CHAR_VERSION, STATE_VERSION}
};
const STATE_TRANSITION g_StateVersionTransitions[] = {
{CHAR_ORIGIN, STATE_ORIGIN}
};
const STATE_TRANSITION g_StateOriginTransitions[] = {
{CHAR_SESSION_NAME, STATE_SESSION_NAME}
};
const STATE_TRANSITION g_StateSessionNameTransitions[] = {
{CHAR_TITLE, STATE_TITLE},
{CHAR_URI, STATE_URI},
{CHAR_EMAIL, STATE_EMAIL},
{CHAR_PHONE, STATE_PHONE},
{CHAR_CONNECTION, STATE_CONNECTION}
};
const STATE_TRANSITION g_StateTitleTransitions[] = {
{CHAR_URI, STATE_URI},
{CHAR_EMAIL, STATE_EMAIL},
{CHAR_PHONE, STATE_PHONE},
{CHAR_CONNECTION, STATE_CONNECTION}
};
const STATE_TRANSITION g_StateUriTransitions[] = {
{CHAR_EMAIL, STATE_EMAIL},
{CHAR_PHONE, STATE_PHONE},
{CHAR_CONNECTION, STATE_CONNECTION}
};
const STATE_TRANSITION g_StateEmailTransitions[] = {
{CHAR_EMAIL, STATE_EMAIL},
{CHAR_PHONE, STATE_PHONE},
{CHAR_CONNECTION, STATE_CONNECTION}
};
const STATE_TRANSITION g_StatePhoneTransitions[] = {
{CHAR_PHONE, STATE_PHONE},
{CHAR_CONNECTION, STATE_CONNECTION}
};
const STATE_TRANSITION g_StateConnectionTransitions[] = {
{CHAR_BANDWIDTH, STATE_BANDWIDTH},
{CHAR_TIME, STATE_TIME},
{CHAR_KEY, STATE_KEY},
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateBandwidthTransitions[] = {
{CHAR_TIME, STATE_TIME},
{CHAR_KEY, STATE_KEY},
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateTimeTransitions[] = {
{CHAR_TIME, STATE_TIME},
{CHAR_REPEAT, STATE_REPEAT},
{CHAR_ADJUSTMENT, STATE_ADJUSTMENT},
{CHAR_KEY, STATE_KEY},
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateRepeatTransitions[] = {
{CHAR_TIME, STATE_TIME},
{CHAR_REPEAT, STATE_REPEAT},
{CHAR_ADJUSTMENT, STATE_ADJUSTMENT},
{CHAR_KEY, STATE_KEY},
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateAdjustmentTransitions[] = {
{CHAR_KEY, STATE_KEY},
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateKeyTransitions[] = {
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateAttributeTransitions[] = {
{CHAR_ATTRIBUTE, STATE_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
const STATE_TRANSITION g_StateMediaTransitions[] = {
{CHAR_MEDIA, STATE_MEDIA},
{CHAR_MEDIA_TITLE, STATE_MEDIA_TITLE},
{CHAR_MEDIA_CONNECTION, STATE_MEDIA_CONNECTION},
{CHAR_MEDIA_BANDWIDTH, STATE_MEDIA_BANDWIDTH},
{CHAR_MEDIA_KEY, STATE_MEDIA_KEY},
{CHAR_MEDIA_ATTRIBUTE, STATE_MEDIA_ATTRIBUTE}
};
const STATE_TRANSITION g_StateMediaTitleTransitions[] = {
{CHAR_MEDIA, STATE_MEDIA},
{CHAR_MEDIA_CONNECTION, STATE_MEDIA_CONNECTION},
{CHAR_MEDIA_BANDWIDTH, STATE_MEDIA_BANDWIDTH},
{CHAR_MEDIA_KEY, STATE_MEDIA_KEY},
{CHAR_MEDIA_ATTRIBUTE, STATE_MEDIA_ATTRIBUTE}
};
const STATE_TRANSITION g_StateMediaConnectionTransitions[]= {
{CHAR_MEDIA, STATE_MEDIA},
{CHAR_MEDIA_BANDWIDTH, STATE_MEDIA_BANDWIDTH},
{CHAR_MEDIA_KEY, STATE_MEDIA_KEY},
{CHAR_MEDIA_ATTRIBUTE, STATE_MEDIA_ATTRIBUTE}
};
const STATE_TRANSITION g_StateMediaBandwidthTransitions[]= {
{CHAR_MEDIA, STATE_MEDIA},
{CHAR_MEDIA_KEY, STATE_MEDIA_KEY},
{CHAR_MEDIA_ATTRIBUTE, STATE_MEDIA_ATTRIBUTE}
};
const STATE_TRANSITION g_StateMediaKeyTransitions[] = {
{CHAR_MEDIA, STATE_MEDIA},
{CHAR_MEDIA_ATTRIBUTE, STATE_MEDIA_ATTRIBUTE}
};
const STATE_TRANSITION g_StateMediaAttributeTransitions[]={
{CHAR_MEDIA, STATE_MEDIA},
{CHAR_MEDIA_ATTRIBUTE, STATE_MEDIA_ATTRIBUTE},
{CHAR_MEDIA, STATE_MEDIA}
};
// const state transition table definition
const TRANSITION_INFO g_TransitionTable[STATE_NUM_STATES] = {
STATE_TRANSITION_ENTRY(STATE_START, g_StateStartTransitions),
STATE_TRANSITION_ENTRY(STATE_VERSION, g_StateVersionTransitions),
STATE_TRANSITION_ENTRY(STATE_ORIGIN, g_StateOriginTransitions),
STATE_TRANSITION_ENTRY(STATE_SESSION_NAME, g_StateSessionNameTransitions),
STATE_TRANSITION_ENTRY(STATE_TITLE, g_StateTitleTransitions),
STATE_TRANSITION_ENTRY(STATE_URI, g_StateUriTransitions),
STATE_TRANSITION_ENTRY(STATE_EMAIL, g_StateEmailTransitions),
STATE_TRANSITION_ENTRY(STATE_PHONE, g_StatePhoneTransitions),
STATE_TRANSITION_ENTRY(STATE_CONNECTION, g_StateConnectionTransitions),
STATE_TRANSITION_ENTRY(STATE_BANDWIDTH, g_StateBandwidthTransitions),
STATE_TRANSITION_ENTRY(STATE_TIME, g_StateTimeTransitions),
STATE_TRANSITION_ENTRY(STATE_REPEAT, g_StateRepeatTransitions),
STATE_TRANSITION_ENTRY(STATE_ADJUSTMENT, g_StateAdjustmentTransitions),
STATE_TRANSITION_ENTRY(STATE_KEY, g_StateKeyTransitions),
STATE_TRANSITION_ENTRY(STATE_ATTRIBUTE, g_StateAttributeTransitions),
STATE_TRANSITION_ENTRY(STATE_MEDIA, g_StateMediaTransitions),
STATE_TRANSITION_ENTRY(STATE_MEDIA_TITLE, g_StateMediaTitleTransitions),
STATE_TRANSITION_ENTRY(STATE_MEDIA_CONNECTION, g_StateMediaConnectionTransitions),
STATE_TRANSITION_ENTRY(STATE_MEDIA_BANDWIDTH, g_StateMediaBandwidthTransitions),
STATE_TRANSITION_ENTRY(STATE_MEDIA_KEY, g_StateMediaKeyTransitions),
STATE_TRANSITION_ENTRY(STATE_MEDIA_ATTRIBUTE, g_StateMediaAttributeTransitions)
};
BOOL
SDP::Init(
)
{
// check if already initialized
if ( NULL != m_MediaList )
{
SetLastError(ERROR_ALREADY_INITIALIZED);
return FALSE;
}
// create media and time lists
// set flags to destroy them when the sdp instance destructs
try
{
m_MediaList = new SDP_MEDIA_LIST;
}
catch(...)
{
m_MediaList = NULL;
}
if ( NULL == m_MediaList )
{
SetLastError(ERROR_NOT_ENOUGH_MEMORY);
return FALSE;
}
m_DestroyMediaList = TRUE;
try
{
m_TimeList = new SDP_TIME_LIST;
}
catch(...)
{
m_TimeList = NULL;
}
if ( NULL == m_TimeList )
{
SetLastError(ERROR_NOT_ENOUGH_MEMORY);
return FALSE;
}
m_DestroyTimeList = TRUE;
return TRUE;
}
// determine the character set implicit from the packet
BOOL
SDP::DetermineCharacterSet(
IN CHAR *SdpPacket,
OUT SDP_CHARACTER_SET &CharacterSet
)
{
ASSERT(NULL != SdpPacket);
// search for charset string (attribute "\na=charset:")
CHAR *AttributeString = strstr(SdpPacket, SDP_CHARACTER_SET_STRING);
// check if the character set is supplied
if ( NULL == AttributeString )
{
// ASCII is the default character set
CharacterSet = CS_ASCII;
return TRUE;
}
else
{
// the character set attribute string must be present before the first media field
CHAR *FirstMediaField = strstr(SdpPacket, MEDIA_SEARCH_STRING);
// there is a media field and it doesn't occur after the character set string, signal error
if ( (NULL != FirstMediaField) &&
(FirstMediaField <= AttributeString) )
{
SetLastError(SDP_INVALID_CHARACTER_SET_FORMAT);
return FALSE;
}
// advance attribute string beyond the attribute specification
AttributeString += SDP_CHARACTER_SET_STRLEN;
// compare the character set string with each of the well known
// character set strings
for ( UINT i=0; i < NUM_SDP_CHARACTER_SET_ENTRIES; i++ )
{
// NOTE: no need to null terminate the character string as
// strncmp will return on finding the first character that
// doesn't match
if ( !strncmp(
AttributeString,
SDP_CHARACTER_SET_TABLE[i].m_CharSetString,
SDP_CHARACTER_SET_TABLE[i].m_Length
) )
{
CharacterSet = SDP_CHARACTER_SET_TABLE[i].m_CharSetCode;
return TRUE;
}
}
// unrecognized character set
SetLastError(SDP_INVALID_CHARACTER_SET);
return FALSE;
}
// the code should not reach here
ASSERT(FALSE);
}
/*
Assumption: We are at the start of a new line. There may or may not be a
new line character before current
*/
BOOL
SDP::GetType(
OUT CHAR &Type,
OUT BOOL &EndOfPacket
)
{
// ensure that we don't peek beyond the end of the string
if ( EOS == m_Current[0] )
{
EndOfPacket = TRUE;
return TRUE;
}
// check if the second char is EQUAL_CHAR
if ( CHAR_EQUAL != m_Current[1] )
{
SetLastError(SDP_INVALID_FORMAT);
return FALSE;
}
EndOfPacket = FALSE;
Type = m_Current[0];
return TRUE;
}
BOOL
SDP::CheckTransition(
IN CHAR Type,
IN PARSE_STATE CurrentParseState,
OUT PARSE_STATE &NewParseState
)
{
// validate the current state
ASSERT(STATE_NUM_STATES > CurrentParseState);
// validate transition table entry
ASSERT(g_TransitionTable[CurrentParseState].m_ParseState == CurrentParseState);
// see if such a trigger exists for the current state
for( UINT i=0; i < g_TransitionTable[CurrentParseState].m_NumTransitions; i++ )
{
// check if trigger has been found
if ( Type == g_TransitionTable[CurrentParseState].m_Transitions[i].m_Type )
{
NewParseState = g_TransitionTable[CurrentParseState].m_Transitions[i].m_NewParseState;
break;
}
}
// check if a trigger was found
if ( g_TransitionTable[CurrentParseState].m_NumTransitions <= i )
{
SetLastError(SDP_INVALID_FORMAT);
return FALSE;
}
return TRUE;
}
BOOL
SDP::GetValue(
IN CHAR Type
)
{
PARSE_STATE NewParseState;
// check if such a transition (current parse state --Type--> new parse state) exists
if ( !CheckTransition(Type, m_ParseState, NewParseState) )
{
return FALSE;
}
BOOL LineParseResult = FALSE;
// fire corresponding action
switch(NewParseState)
{
case STATE_VERSION:
{
LineParseResult = m_ProtocolVersion.ParseLine(m_Current);
}
break;
case STATE_ORIGIN:
{
LineParseResult = m_Origin.ParseLine(m_Current);
}
break;
case STATE_SESSION_NAME:
{
LineParseResult = m_SessionName.ParseLine(m_Current);
}
break;
case STATE_TITLE:
{
LineParseResult = m_SessionTitle.ParseLine(m_Current);
}
break;
case STATE_URI:
{
LineParseResult = m_Uri.ParseLine(m_Current);
}
break;
case STATE_EMAIL:
{
LineParseResult = m_EmailList.ParseLine(m_Current);
}
break;
case STATE_PHONE:
{
LineParseResult = m_PhoneList.ParseLine(m_Current);
}
break;
case STATE_CONNECTION:
{
LineParseResult = m_Connection.ParseLine(m_Current);
}
break;
case STATE_BANDWIDTH:
{
LineParseResult = m_Bandwidth.ParseLine(m_Current);
}
break;
case STATE_TIME:
{
LineParseResult = GetTimeList().ParseLine(m_Current);
}
break;
case STATE_REPEAT:
{
ParseMember(SDP_TIME, GetTimeList(), SDP_REPEAT_LIST, GetRepeatList, m_Current, LineParseResult);
}
break;
case STATE_ADJUSTMENT:
{
LineParseResult = GetTimeList().GetAdjustment().ParseLine(m_Current);
}
break;
case STATE_KEY:
{
LineParseResult = m_EncryptionKey.ParseLine(m_Current);
}
break;
case STATE_ATTRIBUTE:
{
LineParseResult = m_AttributeList.ParseLine(m_Current);
}
break;
case STATE_MEDIA:
{
LineParseResult = GetMediaList().ParseLine(m_Current);
}
break;
case STATE_MEDIA_TITLE:
{
ParseMember(SDP_MEDIA, GetMediaList(), SDP_REQD_BSTRING_LINE, GetTitle, m_Current, LineParseResult);
}
break;
case STATE_MEDIA_CONNECTION:
{
ParseMember(SDP_MEDIA, GetMediaList(), SDP_CONNECTION, GetConnection, m_Current, LineParseResult);
}
break;
case STATE_MEDIA_BANDWIDTH:
{
ParseMember(SDP_MEDIA, GetMediaList(), SDP_BANDWIDTH, GetBandwidth, m_Current, LineParseResult);
}
break;
case STATE_MEDIA_KEY:
{
ParseMember(SDP_MEDIA, GetMediaList(), SDP_ENCRYPTION_KEY, GetEncryptionKey, m_Current, LineParseResult);
}
break;
case STATE_MEDIA_ATTRIBUTE:
{
ParseMember(SDP_MEDIA, GetMediaList(), SDP_ATTRIBUTE_LIST, GetAttributeList, m_Current, LineParseResult);
}
break;
default:
{
// should never reach here
ASSERT(FALSE);
SetLastError(SDP_INVALID_FORMAT);
return FALSE;
}
break;
};
// check if parsing the line succeeded
if ( !LineParseResult )
{
return FALSE;
}
// change to the new state
m_ParseState = NewParseState;
return TRUE;
}
BOOL
SDP::IsValidEndState(
) const
{
if ( (STATE_CONNECTION <= m_ParseState) &&
(STATE_NUM_STATES > m_ParseState) )
{
return TRUE;
}
SetLastError(SDP_INVALID_FORMAT);
return FALSE;
}
void
SDP::Reset(
)
{
// perform the destructor actions (release any allocated resources)
// free the sdp packet if one was created
if ( NULL != m_SdpPacket )
{
delete m_SdpPacket;
m_SdpPacket = NULL;
}
// perform the constructor actions (initialize variables, resources)
// initialize the parse state
m_ParseState = STATE_START;
m_LastGenFailed = FALSE;
m_BytesAllocated = 0;
m_SdpPacketLength = 0;
m_Current = NULL;
m_ParseState = STATE_START;
// m_CharacterSet - nothing needs to be set
m_CharacterSet = CS_UTF8;
// reset the member instances
m_ProtocolVersion.Reset();
m_Origin.Reset();
m_SessionName.Reset();
m_SessionTitle.Reset();
m_Uri.Reset();
m_EmailList.Reset();
m_PhoneList.Reset();
m_Connection.Reset();
m_Bandwidth.Reset();
GetTimeList().Reset();
m_EncryptionKey.Reset();
m_AttributeList.Reset();
GetMediaList().Reset();
}
BOOL
SDP::ParseSdpPacket(
IN CHAR *SdpPacket,
IN SDP_CHARACTER_SET CharacterSet
)
{
ASSERT(NULL != m_MediaList);
ASSERT(NULL != m_TimeList);
// check if the instance has already parsed an sdp packet
if ( NULL != m_Current )
{
// reset the instance and try to parse the sdp packet
Reset();
}
// check if the passed in parameters are valid
if ( (NULL == SdpPacket) || (CS_INVALID == CharacterSet) )
{
SetLastError(SDP_INVALID_PARAMETER);
return FALSE;
}
// point the current pointer to the start of sdp packet
m_Current = SdpPacket;
// if the character set has not yet been determined
if ( CS_IMPLICIT == CharacterSet )
{
// determine the character set
if ( !DetermineCharacterSet(SdpPacket, m_CharacterSet) )
{
return FALSE;
}
}
else // it cannot be CS_UNRECOGNIZED (checked on entry)
{
ASSERT(CS_INVALID != CharacterSet);
m_CharacterSet = CharacterSet;
}
// set the character sets for all the SDP_BSTRING instances that make up the SDP description
m_Origin.GetUserName().SetCharacterSet(m_CharacterSet);
m_SessionName.GetBstring().SetCharacterSet(m_CharacterSet);
m_SessionTitle.GetBstring().SetCharacterSet(m_CharacterSet);
m_EmailList.SetCharacterSet(m_CharacterSet);
m_PhoneList.SetCharacterSet(m_CharacterSet);
// set the character set for the SDP_MEDIA_LIST instance
GetMediaList().SetCharacterSet(m_CharacterSet);
// parse the type and its value for each line in the sdp packet
do
{
BOOL EndOfPacket;
CHAR Type;
// get the next type
if ( !GetType(Type, EndOfPacket) )
{
return FALSE;
}
if ( EndOfPacket )
{
break;
}
// advance the current pointer to beyond the Type= fields
m_Current+=2;
// get the value for the specified type
if ( !GetValue(Type) )
{
return FALSE;
}
}
while ( 1 );
// validate if the parsing state is a valid end state
if ( !IsValidEndState() )
{
return FALSE;
}
return TRUE;
}
// clears the modified state for each member field/value
// this is used in sdpblb.dll to clear the modified state (when an sdp
// is parsed in, the state of all parsed in fields/values is modified) and
// the m_WasModified dirty flag
void
SDP::ClearModifiedState(
)
{
m_ProtocolVersion.GetCharacterStringSize();
m_Origin.GetCharacterStringSize();
m_SessionName.GetCharacterStringSize();
m_SessionTitle.GetCharacterStringSize();
m_Uri.GetCharacterStringSize();
m_EmailList.GetCharacterStringSize();
m_PhoneList.GetCharacterStringSize();
m_Connection.GetCharacterStringSize();
m_Bandwidth.GetCharacterStringSize();
GetTimeList().GetCharacterStringSize();
m_EncryptionKey.GetCharacterStringSize();
m_AttributeList.GetCharacterStringSize();
GetMediaList().GetCharacterStringSize();
}
BOOL
SDP::IsValid(
)
{
// query only the mandatory values
return
m_ProtocolVersion.IsValid() &&
m_Origin.IsValid() &&
m_SessionName.IsValid() &&
m_Connection.IsValid();
}
BOOL
SDP::IsModified(
)
{
ASSERT(IsValid());
return
m_ProtocolVersion.IsModified() ||
m_Origin.IsModified() ||
m_SessionName.IsModified() ||
m_SessionTitle.IsModified() ||
m_Uri.IsModified() ||
m_EmailList.IsModified() ||
m_PhoneList.IsModified() ||
m_Connection.IsModified() ||
m_Bandwidth.IsModified() ||
GetTimeList().IsModified() ||
m_EncryptionKey.IsModified() ||
m_AttributeList.IsModified() ||
GetMediaList().IsModified();
}
// an sdp packet is not generated the way a line is generated (using a SeparatorChar and
// an sdp field carray). this is mainly because these carrays will have to be modified on
// insertion of email and phone lists, media fields and attribute lists or specification of
// other optional sdp properties.
CHAR *
SDP::GenerateSdpPacket(
)
{
// check if valid
if ( !IsValid() )
{
return NULL;
}
// check if the sdp packet needs to be regenerated
// (if the sdp packet exists and no modifications have taken place since
// the last time)
BOOL HasChangedSinceLast = IsModified();
if ( (!m_LastGenFailed) && (NULL != m_SdpPacket) && !HasChangedSinceLast )
{
return m_SdpPacket;
}
// determine the length of character string
m_SdpPacketLength =
m_ProtocolVersion.GetCharacterStringSize() +
m_Origin.GetCharacterStringSize() +
m_SessionName.GetCharacterStringSize() +
m_SessionTitle.GetCharacterStringSize() +
m_Uri.GetCharacterStringSize() +
m_EmailList.GetCharacterStringSize() +
m_PhoneList.GetCharacterStringSize() +
m_Connection.GetCharacterStringSize() +
m_Bandwidth.GetCharacterStringSize() +
GetTimeList().GetCharacterStringSize() +
m_EncryptionKey.GetCharacterStringSize() +
m_AttributeList.GetCharacterStringSize() +
GetMediaList().GetCharacterStringSize();
// check if a buffer needs to be allocated, allocate if required
if ( m_BytesAllocated < (m_SdpPacketLength+1) )
{
CHAR * NewSdpPacket;
try
{
NewSdpPacket = new CHAR[m_SdpPacketLength+1];
}
catch(...)
{
NewSdpPacket = NULL;
}
if (NewSdpPacket == NULL)
{
m_LastGenFailed = TRUE;
return NULL;
}
// if we have an old sdp packet, get rid of it now
if ( NULL != m_SdpPacket )
{
delete m_SdpPacket;
}
m_SdpPacket = NewSdpPacket;
m_BytesAllocated = m_SdpPacketLength+1;
}
// fill in the buffer
ostrstream OutputStream(m_SdpPacket, m_BytesAllocated);
// if this method ever fails here for this instance, further calls to the
// method without modification will return a ptr
if ( !( m_ProtocolVersion.PrintValue(OutputStream) &&
m_Origin.PrintValue(OutputStream) &&
m_SessionName.PrintValue(OutputStream) &&
m_SessionTitle.PrintValue(OutputStream) &&
m_Uri.PrintValue(OutputStream) &&
m_EmailList.PrintValue(OutputStream) &&
m_PhoneList.PrintValue(OutputStream) &&
m_Connection.PrintValue(OutputStream) &&
m_Bandwidth.PrintValue(OutputStream) &&
GetTimeList().PrintValue(OutputStream) &&
m_EncryptionKey.PrintValue(OutputStream) &&
m_AttributeList.PrintValue(OutputStream) &&
GetMediaList().PrintValue(OutputStream) )
)
{
m_LastGenFailed = TRUE;
return NULL;
}
OutputStream << EOS;
m_LastGenFailed = FALSE;
// dirty flag - is initially false and is set to TRUE when an sdp is generated because it had
// been modified since the last time the sdp was generated.
// NOTE: at this point IsModified() is false, so m_WasModified captures the fact that
// the sdp was modified at some point
if ( !m_WasModified && HasChangedSinceLast )
{
m_WasModified = TRUE;
}
return m_SdpPacket;
}
SDP::~SDP(
)
{
if ( NULL != m_SdpPacket )
{
delete m_SdpPacket;
}
if ( m_DestroyMediaList && (NULL != m_MediaList) )
{
delete m_MediaList;
}
if ( m_DestroyTimeList && (NULL != m_TimeList) )
{
delete m_TimeList;
}
}