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openbts/GSM/GSMConfig.cpp

675 lines
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C++

/*
* Copyright 2008, 2009, 2010, 2014 Free Software Foundation, Inc.
* Copyright 2014 Range Networks, Inc.
*
* This software is distributed under multiple licenses; see the COPYING file in the main directory for licensing information for this specific distribution.
*
* This use of this software may be subject to additional restrictions.
* See the LEGAL file in the main directory for details.
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.
*/
#define LOG_GROUP LogGroup::GSM // Can set Log.Level.GSM for debugging
#include "GSMConfig.h"
#include "GSMTransfer.h"
#include "GSMLogicalChannel.h"
#include "GSMCCCH.h"
#include "GPRSExport.h"
#include <ControlCommon.h>
#include <Logger.h>
#include <NeighborTable.h>
#include <Reporting.h>
#include <Globals.h>
using namespace std;
using namespace GSM;
using Control::L3LogicalChannel;
extern void PagerStart();
int GSM::gNumC7s, GSM::gNumC1s; // Number of C7 and C1 timelots created.
static bool testStart = false; // Set this to try testing without the channels started.
bool GSM::isCBSEnabled() {
return gConfig.getStr("Control.SMSCB.Table").length() != 0;
}
GSMConfig::GSMConfig()
:mCBCH(NULL),
mSI5Frame(SAPI0Sacch,L3_UNIT_DATA),mSI6Frame(SAPI0Sacch,L3_UNIT_DATA),
mSI1(NULL),mSI2(NULL),mSI3(NULL),mSI4(NULL),
mSI5(NULL),mSI6(NULL), mSI13(NULL),
mStartTime(::time(NULL)),
mChangemark(0)
{
}
void GSMConfig::gsmInit()
{
// (pat 3-2014) Because the changemark was always inited to 0, if you kill OpenBTS, change something that affects the beacon,
// and restart, the handsets do not know the beacon has changed. We need the changemark to be persistent across restarts.
// As a sneaky dirty way to do this, I am putting it in the config database.
const char *GsmChangeMark = "GSM.ChangeMark";
if (gConfig.defines(GsmChangeMark)) {
mChangemark = gConfig.getNum(GsmChangeMark) % 8;
}
long changed = 0;
long band = gConfig.getNum("GSM.Radio.Band");
long c0 = gConfig.getNum("GSM.Radio.C0");
// We do not init this statically because it must be done after config options are inited.
gControlChannelDescription = new L3ControlChannelDescription();
gControlChannelDescription->validate();
// adjust to an appropriate band if C0 is bogus
if (c0 >= 128 && c0 <= 251 && band != 850) {
changed = band;
band = 850;
} else if (c0 <= 124 && band != 900) {
changed = band;
band = 900;
} else if (c0 >= 975 && c0 <= 1023 && band != 900) {
changed = band;
band = 900;
} else if (c0 >= 512 && c0 <= 810 && band != 1800 && band != 1900) {
changed = band;
band = 1800;
} else if (c0 >= 811 && c0 <= 885 && band != 1800) {
changed = band;
band = 1800;
}
if (changed) {
if (gConfig.set("GSM.Radio.Band", band)) {
LOG(NOTICE) << "crisis averted: automatically adjusted GSM.Radio.Band from " << changed << " to " << band << " so GSM.Radio.C0 is in range";
} else {
LOG(ERR) << "unable to automatically adjust GSM.Radio.Band, config write error";
}
}
mBand = (GSMBand)gConfig.getNum("GSM.Radio.Band");
regenerateBeacon();
}
void GSMConfig::gsmStart()
{
// If requested, start gprs to allocate channels at startup.
// Otherwise, channels are allocated on demand, if possible.
if (GPRS::GPRSConfig::IsEnabled()) {
// Start gprs.
GPRS::gprsStart();
}
gPowerManager.pmStart();
// Do not call this until the paging channels are installed.
PagerStart();
Control::l3start(); // (pat) For the L3 rewrite: start the L3 state machine dispatcher.
}
void GSMConfig::regenerateBeacon()
{
// (pat) regenerateBeacon is called whenever there is a change to the config database.
// When we call gConfig.set() it would cause infinite recursion; this prevents that, albeit goofily.
// This is not safe in case someone later installs throws that jump over this.
static int noRecursionPlease = 0;
if (noRecursionPlease) return;
noRecursionPlease++;
gReports.incr("OpenBTS.GSM.RR.BeaconRegenerated");
mChangemark++;
gConfig.set("GSM.ChangeMark",mChangemark);
// Update everything from the configuration.
LOG(NOTICE) << "regenerating system information messages, changemark " << mChangemark;
// BSIC components
mNCC = gConfig.getNum("GSM.Identity.BSIC.NCC");
LOG_ASSERT(mNCC<8);
mBCC = gConfig.getNum("GSM.Identity.BSIC.BCC");
LOG_ASSERT(mBCC<8);
// MCC/MNC/LAC
mLAI = L3LocationAreaIdentity();
std::vector<unsigned> neighbors = gNeighborTable.ARFCNList();
// if the neighbor list is emtpy, put ourselves on it
if (neighbors.size()==0) neighbors.push_back(gConfig.getNum("GSM.Radio.C0"));
// Now regenerate all of the system information messages.
// SI1
L3SystemInformationType1 *SI1 = new L3SystemInformationType1;
if (mSI1) delete mSI1;
mSI1 = SI1;
LOG(INFO) << *SI1;
L3Frame SI1L3(L3_UNIT_DATA,0);
SI1->write(SI1L3);
L2Header SI1Header(L2Length(SI1L3.L2Length()));
mSI1Frame = L2Frame(SI1Header,SI1L3);
LOG(DEBUG) << "mSI1Frame " << mSI1Frame;
// SI2
L3SystemInformationType2 *SI2 = new L3SystemInformationType2(neighbors);
if (mSI2) delete mSI2;
mSI2 = SI2;
LOG(INFO) << *SI2;
L3Frame SI2L3(L3_UNIT_DATA,0);
SI2->write(SI2L3);
L2Header SI2Header(L2Length(SI2L3.L2Length()));
mSI2Frame = L2Frame(SI2Header,SI2L3);
LOG(DEBUG) << "mSI2Frame " << mSI2Frame;
// SI3
L3SystemInformationType3 *SI3 = new L3SystemInformationType3;
if (mSI3) delete mSI3;
mSI3 = SI3;
LOG(INFO) << *SI3;
L3Frame SI3L3(L3_UNIT_DATA,0);
SI3->write(SI3L3);
L2Header SI3Header(L2Length(SI3L3.L2Length()));
mSI3Frame = L2Frame(SI3Header,SI3L3,true);
LOG(DEBUG) << "mSI3Frame " << mSI3Frame;
// SI4
L3SystemInformationType4 *SI4 = new L3SystemInformationType4;
if (mSI4) delete mSI4;
mSI4 = SI4;
LOG(INFO) << *SI4;
LOG(INFO) << SI4;
L3Frame SI4L3(L3_UNIT_DATA,0);
SI4->write(SI4L3);
//printf("SI4 bodylength=%d l2len=%d\n",SI4.l2BodyLength(),SI4L3.L2Length());
//printf("SI4L3.size=%d\n",SI4L3.size());
L2Header SI4Header(L2Length(SI4L3.L2Length()));
mSI4Frame = L2Frame(SI4Header,SI4L3,true);
LOG(DEBUG) << "mSI4Frame " << mSI4Frame;
#if GPRS_PAT | GPRS_TEST
// SI13. pat added 8-2011 to advertise GPRS support.
if (mSI13) { delete mSI13; mSI13 = NULL; }
if (GPRS::GPRSConfig::IsEnabled()) {
mSI13 = new L3SystemInformationType13;
LOG(INFO) << *mSI13;
L3Frame SI13L3(L3_UNIT_DATA,0);
//printf("start=%d\n",SI13L3.size());
mSI13->write(SI13L3);
//printf("end=%d\n",SI13L3.size());
//printf("SI13 bodylength=%d l2len=%d\n",SI13.l2BodyLength(),SI13L3.L2Length());
//printf("SI13L3.size=%d\n",SI13L3.size());
L2Header SI13Header(L2Length(SI13L3.L2Length()));
mSI13Frame = L2Frame(SI13Header,SI13L3,true);
LOG(DEBUG) << "mSI13Frame " << mSI13Frame;
}
#endif
// SI5
regenerateSI5();
// SI6
L3SystemInformationType6 *SI6 = new L3SystemInformationType6;
if (mSI6) delete mSI6;
mSI6 = SI6;
LOG(INFO) << *SI6;
SI6->write(mSI6Frame);
LOG(DEBUG) "mSI6Frame " << mSI6Frame;
noRecursionPlease--;
}
void GSMConfig::regenerateSI5()
{
std::vector<unsigned> neighbors = gNeighborTable.ARFCNList();
// if the neighbor list is emtpy, put ourselves on it
if (neighbors.size()==0) neighbors.push_back(gConfig.getNum("GSM.Radio.C0"));
L3SystemInformationType5 *SI5 = new L3SystemInformationType5(neighbors);
if (mSI5) delete mSI5;
mSI5 = SI5;
LOG(INFO) << *SI5;
SI5->write(mSI5Frame);
LOG(DEBUG) << "mSI5Frame " << mSI5Frame;
}
size_t GSMConfig::AGCHLoad() { return getAGCHLoad(); }
size_t GSMConfig::PCHLoad() { return getPCHLoad(); }
template <class ChanType> ChanType* getChan(vector<ChanType*>& chanList, bool forGprs)
{
const unsigned sz = chanList.size();
LOG(DEBUG) << "sz=" << sz;
if (sz==0) return NULL;
// (pat) Dont randomize for GPRS! GPRS requires that channels are returned
// in order for the initial channels allocated on C0.
// We shouldnt randomize at all because we want RR TCH to come from the
// front of the list and GPRS from the back.
unsigned pos = 0;
const char *configRandomize = "GSM.Channels.Randomize";
if (gConfig.defines(configRandomize)) {
if (forGprs) {
// If the parameter is 'required', the gConfig.remove fails, but dont print a zillion messages.
static bool once = true;
if (once) {
LOG(ALERT) << "Config parameter '" << configRandomize << "' is incompatible with GPRS, removed";
once = false;
}
gConfig.remove(configRandomize);
} else {
pos = random() % sz;
}
}
for (unsigned i=0; i<sz; i++, pos = (pos+1)%sz) {
LOG(DEBUG) << "pos=" << pos << " " << i << "/" << sz;
ChanType *chan = chanList[pos];
if (! chan->inUseByGPRS() && chan->recyclable()) return chan;
}
return NULL;
}
// Are the two channels adjacent?
template <class ChanType>
bool testAdjacent(ChanType *ch1, ChanType *ch2)
{
return (ch1->CN() == ch2->CN() && ch1->TN() == ch2->TN()-1);
}
// (pat) Return the goodness of this possible match of gprs channels.
// Higher numbers are gooder.
template <class ChanType>
int testGoodness(vector<ChanType*>& chanList, int lo, int hi)
{
int goodness = 0;
if (lo > 0) {
ChanType *ch1 = chanList[lo-1]; // ch1 is below to ch lo.
if (testAdjacent(ch1,chanList[lo])) {
// The best match is adjacent to other gprs channels.
if (ch1->inUseByGPRS()) { goodness += 2; }
// The next best is an empty adjacent channel.
else if (ch1->recyclable()) { goodness += 1; }
}
}
if (hi < (int)chanList.size()-1) {
ChanType *ch2 = chanList[hi+1]; // ch2 is above ch hi
if (testAdjacent(ch2,chanList[hi])) {
if (ch2->inUseByGPRS()) { goodness += 2; }
else if (ch2->recyclable()) { goodness += 1; }
}
}
return goodness;
}
// (pat) 6-20-2012: To increase the likelihood that GPRS channels will be adjacent,
// GSM RR channels will be allocated from the front of the channel list
// and GPRS from the end.
// This function allocates a group of channels for gprs.
// Look for the largest group of adjacent channels <= groupSize.
// Give preference to channels that are adjacent to channels already
// allocated for gprs, or to empty channels.
// Give second preference to groups near the end of the channel list.
// Return the allocated channels in the array pointed to by results and
// return number of channels found.
template <class ChanType>
static unsigned getChanGroup(vector<ChanType*>& chanList, ChanType **results)
{
const unsigned sz = chanList.size();
if (sz==0) return 0;
const bool backwards = true; // Currently we always search backwards.
// To search forwards, dont forget to invert besti,bestn below
ChanType *prevFreeCh = NULL; // unneeded initialization
int curN = 0; // current number of adjacent free channels.
int bestI=0, bestN=0; // best match
int bestGoodness = 0; // goodness of best match
for (unsigned i=0; i<sz; i++) {
ChanType *chan = chanList[backwards ? sz-i-1 : i];
if (chan->inUseByGPRS()) { continue; }
if (! chan->recyclable()) { continue; }
if (bestN == 0) {
bestI = i;
curN = bestN = 1;
bestGoodness = testGoodness(chanList,bestI,bestN);
} else {
if (testAdjacent<ChanType>(chan,prevFreeCh)) {
curN++; // chan is adjacent to prevCh.
int curGoodness = testGoodness(chanList,i,curN);
if (curN > bestN || (curN == bestN && curGoodness > bestGoodness)) {
// Best so far, so remember it.
bestN = curN;
bestI = i;
bestGoodness = curGoodness;
// optional early termination test
//if (bestN >= groupSize && bestIsAdjacent) { goto finished; }
}
} else {
curN = 0;
}
}
prevFreeCh = chan;
}
int firstIx = sz-bestI-1; // only works if backwards==true
for (int j = 0; j < bestN; j++) {
results[j] = chanList[firstIx+j];
}
return bestN;
}
// Allocate a group of channels for gprs.
// See comments at getChanGroup.
int GSMConfig::getTCHGroup(int groupSize,TCHFACCHLogicalChannel **results)
{
ScopedLock lock(mLock);
int nfound = getChanGroup<TCHFACCHLogicalChannel>(mTCHPool,results);
// limit to channels actually requested
if (groupSize < nfound) {
nfound = groupSize;
}
for (int i = 0; i < nfound; i++) {
results[i]->lcGetL1()->setGPRS(true,NULL);
}
return nfound;
}
SDCCHLogicalChannel *GSMConfig::getSDCCH()
{
ScopedLock lock(mLock);
SDCCHLogicalChannel *chan = getChan<SDCCHLogicalChannel>(mSDCCHPool,0);
if (chan) chan->lcinit();
LOG(DEBUG) <<chan;
return chan;
}
// 6-2014 pat: The channel is now returned with T3101 running but un-started, which means it is not yet transmitting.
// The caller is responsible for setting the Timing Advance and then starting it.
TCHFACCHLogicalChannel *GSMConfig::getTCH(
bool forGPRS, // If true, allocate the channel to gprs, else to RR use.
bool onlyCN0) // If true, allocate only channels on the lowest ARFCN.
{
LOG(DEBUG);
ScopedLock lock(mLock);
//if (GPRS::GPRSDebug) {
// const unsigned sz = mTCHPool.size();
// char buf[300]; int n = 0;
// for (unsigned i=0; i<sz; i++) {
// TCHFACCHLogicalChannel *chan = mTCHPool[i];
// n += sprintf(&buf[n],"ch=%d:%d,g=%d,r=%d ",chan->CN(),chan->TN(),
// chan->inUseByGPRS(),chan->recyclable());
// }
// LOG(WARNING)<<"getTCH list:"<<buf;
//}
TCHFACCHLogicalChannel *chan = getChan<TCHFACCHLogicalChannel>(mTCHPool,forGPRS);
// (pat) We have to open it or set gprs mode before returning to avoid a race.
if (chan) {
// The channels are searched in order from low to high, so if the first channel
// found is not on CN0, we have failed.
//LOG(DEBUG)<<"getTCH returns"<<LOGVAR2("chan->CN",chan->CN());
if (onlyCN0 && chan->CN()) { return NULL; }
if (forGPRS) {
// (pat) Reserves channel for GPRS, but does not start delivering bursts yet.
chan->lcGetL1()->setGPRS(true,NULL);
return chan;
}
gReports.incr("OpenBTS.GSM.RR.ChannelAssignment");
chan->lcinit();
} else {
//LOG(DEBUG)<<"getTCH returns NULL";
}
LOG(DEBUG);
return chan;
}
template <class ChanType> size_t chanAvailable(const vector<ChanType*>& chanList)
{
size_t count = 0;
for (unsigned i=0; i<chanList.size(); i++) {
if (chanList[i]->inUseByGPRS()) { continue; }
if (chanList[i]->recyclable()) count++;
}
return count;
}
size_t GSMConfig::SDCCHAvailable() const
{
ScopedLock lock(mLock);
return chanAvailable<SDCCHLogicalChannel>(mSDCCHPool);
}
size_t GSMConfig::TCHAvailable() const
{
ScopedLock lock(mLock);
return chanAvailable<TCHFACCHLogicalChannel>(mTCHPool);
}
unsigned countActive(const SDCCHList& chanList)
{
unsigned active = 0;
const unsigned sz = chanList.size();
for (unsigned i=0; i<sz; i++) {
if (!chanList[i]->recyclable()) active++;
}
return active;
}
unsigned countActive(const TCHList& chanList)
{
unsigned active = 0;
const unsigned sz = chanList.size();
// Start the search from a random point in the list.
for (unsigned i=0; i<sz; i++) {
if (chanList[i]->inUseByGPRS()) continue;
if (!chanList[i]->recyclable()) active++;
}
return active;
}
unsigned countAvailable(const TCHList& chanList)
{
unsigned available = 0;
const unsigned sz = chanList.size();
// Start the search from a random point in the list.
for (unsigned i=0; i<sz; i++) {
if (chanList[i]->inUseByGPRS()) continue;
available++;
}
return available;
}
unsigned GSMConfig::SDCCHActive() const
{
return countActive(mSDCCHPool);
}
unsigned GSMConfig::TCHActive() const
{
return countActive(mTCHPool);
}
unsigned GSMConfig::TCHTotal() const
{
return countAvailable(mTCHPool);
}
void GSMConfig::createCombination0(TransceiverManager& TRX, unsigned TN)
{
// This channel is a dummy burst generator.
// This should not be applied to C0T0.
LOG_ASSERT(TN!=0);
LOG(NOTICE) << "Configuring dummy filling on C0T " << TN;
ARFCNManager *radio = TRX.ARFCN(0);
radio->setSlot(TN,0); // (pat) 0 => Transciever.h enum ChannelCombination = FILL
}
void GSMConfig::createCombinationI(TransceiverManager& TRX, unsigned CN, unsigned TN)
{
LOG_ASSERT((CN!=0)||(TN!=0));
LOG(NOTICE) << "Configuring combination I on C" << CN << "T" << TN;
ARFCNManager *radio = TRX.ARFCN(CN);
radio->setSlot(TN,1); // (pat) 1 => Transciever.h enum ChannelCombination = I
TCHFACCHLogicalChannel* chan = new TCHFACCHLogicalChannel(CN,TN,gTCHF_T[TN]);
chan->downstream(radio);
Thread* thread = new Thread;
thread->start((void*(*)(void*))Control::DCCHDispatcher,dynamic_cast<L3LogicalChannel*>(chan));
chan->lcinit();
if (CN == 0 && !testStart) chan->lcstart(); // Everything on C0 must broadcast continually.
gBTS.addTCH(chan);
}
class Beacon {};
static Thread CBCHControlThread;
static bool isCBSRunning = false;
void GSMConfig::createCBCH(ARFCNManager *radio, TypeAndOffset type, int CN, int TN)
{
LOG(INFO) << "creating CBCH for SMSCB";
// CBCH is always SDCCH 2 (third one) but may be on any timeslot, depending on beacon type.
CBCHLogicalChannel *CBCH = new CBCHLogicalChannel(CN,TN,type == SDCCH_4_2 ? gSDCCH4[2] : gSDCCH8[2]);
CBCH->downstream(radio);
CBCH->cbchOpen();
gBTS.addCBCH(CBCH);
if (!isCBSRunning) { // As of 8-2014, this is only called once so this test is irrelevant.
isCBSRunning = true;
CBCHControlThread.start((void*(*)(void*))Control::SMSCBSender,NULL);
}
mCBCHDescription = L3ChannelDescription(type,TN,gConfig.getNum("GSM.Identity.BSIC.BCC"),gConfig.getNum("GSM.Radio.C0")+CN);
regenerateBeacon(); // To update SI4 with the new CBCH timeslot.
}
// Combination-5 beacon has 3 x CCCH + 4 x SDCCH.
// There can be only one Combination 5 beacon, always on timeslot 0.
class BeaconC5 : public Beacon {
SCHL1FEC SCH;
FCCHL1FEC FCCH;
BCCHL1FEC BCCH;
RACHL1FEC *RACH;
CCCHLogicalChannel *CCCH;
SDCCHLogicalChannel *C0T0SDCCH[4];
Thread C0T0SDCCHControlThread[4];
public:
BeaconC5(ARFCNManager *radio)
{
LOG(DEBUG);
unsigned TN = 0;
radio->setSlot(TN,5);
SCH.downstream(radio);
SCH.l1open();
FCCH.downstream(radio);
FCCH.l1open();
BCCH.downstream(radio);
BCCH.l1open();
RACH = new RACHL1FEC(gRACHC5Mapping,0);
RACH->downstream(radio);
RACH->l1open();
CCCH = new CCCHLogicalChannel(0, gCCCH_C5Mapping); // Always ccch_grooup == 0
CCCH->downstream(radio);
CCCH->ccchOpen();
// C-V C0T0 SDCCHs
C0T0SDCCH[0] = new SDCCHLogicalChannel(0,0,gSDCCH_4_0);
C0T0SDCCH[1] = new SDCCHLogicalChannel(0,0,gSDCCH_4_1);
C0T0SDCCH[2] = new SDCCHLogicalChannel(0,0,gSDCCH_4_2);
C0T0SDCCH[3] = new SDCCHLogicalChannel(0,0,gSDCCH_4_3);
// GSM 5.02 6.4.1: Subchannel 2 used for CBCH if CBS enabled.
// (pat) CBCH location is advertised in L3SystemInformationType4.
bool SMSCB = isCBSEnabled();
for (int i=0; i<4; i++) {
if (SMSCB && (i==2)) continue;
C0T0SDCCH[i]->downstream(radio);
C0T0SDCCHControlThread[i].start((void*(*)(void*))Control::DCCHDispatcher,dynamic_cast<L3LogicalChannel*>(C0T0SDCCH[i]));
C0T0SDCCH[i]->lcinit();
C0T0SDCCH[i]->lcstart(); // Everything on channel 0 needs to broadcast constantly.
gBTS.addSDCCH(C0T0SDCCH[i]);
}
// Install CBCH if used.
if (SMSCB) {
gBTS.createCBCH(radio,SDCCH_4_2,0,0);
}
}
};
void GSMConfig::createBeacon(ARFCNManager *radio)
{
new BeaconC5(radio);
}
void GSMConfig::createCombinationVII(TransceiverManager& TRX, unsigned CN, unsigned TN)
{
LOG_ASSERT((CN!=0)||(TN!=0));
LOG(NOTICE) << "Configuring combination VII on C" << CN << "T" << TN;
ARFCNManager *radio = TRX.ARFCN(CN);
radio->setSlot(TN,7); // (pat) 7 => Transciever.h enum ChannelCombination = VII
for (int i=0; i<8; i++) {
SDCCHLogicalChannel* chan = new SDCCHLogicalChannel(CN,TN,gSDCCH8[i]);
chan->downstream(radio);
Thread* thread = new Thread;
thread->start((void*(*)(void*))Control::DCCHDispatcher,dynamic_cast<L3LogicalChannel*>(chan));
chan->lcinit();
if (CN == 0 && !testStart) chan->lcstart(); // Everything on C0 must broadcast continually.
gBTS.addSDCCH(chan);
}
}
void GSMConfig::setBtsHold(bool val)
{
ScopedLock lock(mLock);
mHold = val;
}
bool GSMConfig::btsHold() const
{
ScopedLock lock(mLock);
return mHold;
}
// (pat) Return a vector of the available channels.
// Use to avoid publishing these iterators to the universe.
void GSMConfig::getChanVector(L2ChanList &result)
{
result.clear();
result.reserve(64); // Enough for a 2 ARFCN system.
for (GSM::SDCCHList::const_iterator sChanItr = gBTS.SDCCHPool().begin(); sChanItr != gBTS.SDCCHPool().end(); ++sChanItr) {
result.push_back(*sChanItr);
}
// TCHs
for (GSM::TCHList::const_iterator tChanItr = gBTS.TCHPool().begin(); tChanItr != gBTS.TCHPool().end(); ++tChanItr) {
result.push_back(*tChanItr);
}
}
// vim: ts=4 sw=4