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/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/modules/rtp_rtcp/source/ssrc_database.h"
#include <assert.h>
#include <stdlib.h>
#include "webrtc/system_wrappers/interface/critical_section_wrapper.h"
#ifdef _WIN32
#include <windows.h>
#include <MMSystem.h> //timeGetTime
// TODO(hellner): investigate if it is necessary to disable these warnings.
#pragma warning(disable:4311)
#pragma warning(disable:4312)
#else
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <sys/time.h>
#endif
namespace webrtc {
SSRCDatabase*
SSRCDatabase::StaticInstance(CountOperation count_operation)
{
SSRCDatabase* impl =
GetStaticInstance<SSRCDatabase>(count_operation);
return impl;
}
SSRCDatabase*
SSRCDatabase::GetSSRCDatabase()
{
return StaticInstance(kAddRef);
}
void
SSRCDatabase::ReturnSSRCDatabase()
{
StaticInstance(kRelease);
}
uint32_t
SSRCDatabase::CreateSSRC()
{
CriticalSectionScoped lock(_critSect);
uint32_t ssrc = GenerateRandom();
while(_ssrcMap.find(ssrc) != _ssrcMap.end())
{
ssrc = GenerateRandom();
}
_ssrcMap[ssrc] = 0;
return ssrc;
}
int32_t
SSRCDatabase::RegisterSSRC(const uint32_t ssrc)
{
CriticalSectionScoped lock(_critSect);
_ssrcMap[ssrc] = 0;
return 0;
}
int32_t
SSRCDatabase::ReturnSSRC(const uint32_t ssrc)
{
CriticalSectionScoped lock(_critSect);
_ssrcMap.erase(ssrc);
return 0;
}
SSRCDatabase::SSRCDatabase()
{
// we need to seed the random generator, otherwise we get 26500 each time, hardly a random value :)
#ifdef _WIN32
srand(timeGetTime());
#else
struct timeval tv;
struct timezone tz;
gettimeofday(&tv, &tz);
srand(tv.tv_usec);
#endif
_critSect = CriticalSectionWrapper::CreateCriticalSection();
}
SSRCDatabase::~SSRCDatabase()
{
_ssrcMap.clear();
delete _critSect;
}
uint32_t SSRCDatabase::GenerateRandom()
{
uint32_t ssrc = 0;
do
{
ssrc = rand();
ssrc = ssrc <<16;
ssrc += rand();
} while (ssrc == 0 || ssrc == 0xffffffff);
return ssrc;
}
} // namespace webrtc
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