1 // ***************************************************************************
2 // BamReader_p.cpp (c) 2009 Derek Barnett
3 // Marth Lab, Department of Biology, Boston College
4 // ---------------------------------------------------------------------------
5 // Last modified: 7 October 2011 (DB)
6 // ---------------------------------------------------------------------------
7 // Provides the basic functionality for reading BAM files
8 // ***************************************************************************
10 #include <api/BamConstants.h>
11 #include <api/BamReader.h>
12 #include <api/internal/BamException_p.h>
13 #include <api/internal/BamHeader_p.h>
14 #include <api/internal/BamRandomAccessController_p.h>
15 #include <api/internal/BamReader_p.h>
16 #include <api/internal/BamStandardIndex_p.h>
17 #include <api/internal/BamToolsIndex_p.h>
18 #include <api/internal/BgzfStream_p.h>
19 using namespace BamTools;
20 using namespace BamTools::Internal;
30 BamReaderPrivate::BamReaderPrivate(BamReader* parent)
31 : m_alignmentsBeginOffset(0)
34 m_isBigEndian = BamTools::SystemIsBigEndian();
38 BamReaderPrivate::~BamReaderPrivate(void) {
42 // closes the BAM file
43 bool BamReaderPrivate::Close(void) {
52 // close random access controller
53 m_randomAccessController.Close();
55 // if stream is open, attempt close
59 } catch ( BamException& e ) {
60 const string streamError = e.what();
61 const string message = string("encountered error closing BAM file: \n\t") + streamError;
62 SetErrorString("BamReader::Close", message);
71 // creates an index file of requested type on current BAM file
72 bool BamReaderPrivate::CreateIndex(const BamIndex::IndexType& type) {
74 // skip if BAM file not open
76 SetErrorString("BamReader::CreateIndex", "cannot create index on unopened BAM file");
80 // attempt to create index
81 if ( m_randomAccessController.CreateIndex(this, type) )
84 const string bracError = m_randomAccessController.GetErrorString();
85 const string message = string("could not create index: \n\t") + bracError;
86 SetErrorString("BamReader::CreateIndex", message);
91 // return path & filename of current BAM file
92 const string BamReaderPrivate::Filename(void) const {
96 string BamReaderPrivate::GetErrorString(void) const {
100 // return header data as std::string
101 string BamReaderPrivate::GetHeaderText(void) const {
102 return m_header.ToString();
105 // return header data as SamHeader object
106 SamHeader BamReaderPrivate::GetSamHeader(void) const {
107 return m_header.ToSamHeader();
110 // get next alignment (with character data fully parsed)
111 bool BamReaderPrivate::GetNextAlignment(BamAlignment& alignment) {
113 // if valid alignment found
114 if ( GetNextAlignmentCore(alignment) ) {
116 // store alignment's "source" filename
117 alignment.Filename = m_filename;
119 // return success/failure of parsing char data
120 if ( alignment.BuildCharData() )
123 const string alError = alignment.GetErrorString();
124 const string message = string("could not populate alignment data: \n\t") + alError;
125 SetErrorString("BamReader::GetNextAlignment", message);
130 // no valid alignment found
134 // retrieves next available alignment core data (returns success/fail)
135 // ** DOES NOT populate any character data fields (read name, bases, qualities, tag data, filename)
136 // these can be accessed, if necessary, from the supportData
137 // useful for operations requiring ONLY positional or other alignment-related information
138 bool BamReaderPrivate::GetNextAlignmentCore(BamAlignment& alignment) {
142 // skip if region is set but has no alignments
143 if ( m_randomAccessController.HasRegion() &&
144 !m_randomAccessController.RegionHasAlignments() )
149 // if can't read next alignment
150 if ( !LoadNextAlignment(alignment) )
153 // check alignment's region-overlap state
154 BamRandomAccessController::RegionState state = m_randomAccessController.AlignmentState(alignment);
156 // if alignment starts after region, no need to keep reading
157 if ( state == BamRandomAccessController::AfterRegion )
160 // read until overlap is found
161 while ( state != BamRandomAccessController::OverlapsRegion ) {
163 // if can't read next alignment
164 if ( !LoadNextAlignment(alignment) )
167 // check alignment's region-overlap state
168 state = m_randomAccessController.AlignmentState(alignment);
170 // if alignment starts after region, no need to keep reading
171 if ( state == BamRandomAccessController::AfterRegion )
175 // if we get here, we found the next 'valid' alignment
176 // (e.g. overlaps current region if one was set, simply the next alignment if not)
177 alignment.SupportData.HasCoreOnly = true;
180 } catch ( BamException& e ) {
181 const string streamError = e.what();
182 const string message = string("encountered error reading BAM alignment: \n\t") + streamError;
183 SetErrorString("BamReader::GetNextAlignmentCore", message);
188 int BamReaderPrivate::GetReferenceCount(void) const {
189 return m_references.size();
192 const RefVector& BamReaderPrivate::GetReferenceData(void) const {
196 // returns RefID for given RefName (returns References.size() if not found)
197 int BamReaderPrivate::GetReferenceID(const string& refName) const {
199 // retrieve names from reference data
200 vector<string> refNames;
201 RefVector::const_iterator refIter = m_references.begin();
202 RefVector::const_iterator refEnd = m_references.end();
203 for ( ; refIter != refEnd; ++refIter)
204 refNames.push_back( (*refIter).RefName );
206 // return 'index-of' refName (or -1 if not found)
207 int index = distance(refNames.begin(), find(refNames.begin(), refNames.end(), refName));
208 if ( index == (int)m_references.size() ) return -1;
212 bool BamReaderPrivate::HasIndex(void) const {
213 return m_randomAccessController.HasIndex();
216 bool BamReaderPrivate::IsOpen(void) const {
217 return m_stream.IsOpen;
220 // load BAM header data
221 void BamReaderPrivate::LoadHeaderData(void) {
222 m_header.Load(&m_stream);
225 // populates BamAlignment with alignment data under file pointer, returns success/fail
226 bool BamReaderPrivate::LoadNextAlignment(BamAlignment& alignment) {
228 // read in the 'block length' value, make sure it's not zero
229 char buffer[sizeof(uint32_t)];
230 m_stream.Read(buffer, sizeof(uint32_t));
231 alignment.SupportData.BlockLength = BamTools::UnpackUnsignedInt(buffer);
232 if ( m_isBigEndian ) BamTools::SwapEndian_32(alignment.SupportData.BlockLength);
233 if ( alignment.SupportData.BlockLength == 0 )
236 // read in core alignment data, make sure the right size of data was read
237 char x[Constants::BAM_CORE_SIZE];
238 if ( m_stream.Read(x, Constants::BAM_CORE_SIZE) != Constants::BAM_CORE_SIZE )
241 // swap core endian-ness if necessary
242 if ( m_isBigEndian ) {
243 for ( int i = 0; i < Constants::BAM_CORE_SIZE; i+=sizeof(uint32_t) )
244 BamTools::SwapEndian_32p(&x[i]);
247 // set BamAlignment 'core' and 'support' data
248 alignment.RefID = BamTools::UnpackSignedInt(&x[0]);
249 alignment.Position = BamTools::UnpackSignedInt(&x[4]);
251 unsigned int tempValue = BamTools::UnpackUnsignedInt(&x[8]);
252 alignment.Bin = tempValue >> 16;
253 alignment.MapQuality = tempValue >> 8 & 0xff;
254 alignment.SupportData.QueryNameLength = tempValue & 0xff;
256 tempValue = BamTools::UnpackUnsignedInt(&x[12]);
257 alignment.AlignmentFlag = tempValue >> 16;
258 alignment.SupportData.NumCigarOperations = tempValue & 0xffff;
260 alignment.SupportData.QuerySequenceLength = BamTools::UnpackUnsignedInt(&x[16]);
261 alignment.MateRefID = BamTools::UnpackSignedInt(&x[20]);
262 alignment.MatePosition = BamTools::UnpackSignedInt(&x[24]);
263 alignment.InsertSize = BamTools::UnpackSignedInt(&x[28]);
265 // set BamAlignment length
266 alignment.Length = alignment.SupportData.QuerySequenceLength;
268 // read in character data - make sure proper data size was read
269 bool readCharDataOK = false;
270 const unsigned int dataLength = alignment.SupportData.BlockLength - Constants::BAM_CORE_SIZE;
271 RaiiBuffer allCharData(dataLength);
273 if ( m_stream.Read(allCharData.Buffer, dataLength) == dataLength ) {
275 // store 'allCharData' in supportData structure
276 alignment.SupportData.AllCharData.assign((const char*)allCharData.Buffer, dataLength);
279 readCharDataOK = true;
282 // need to calculate this here so that BamAlignment::GetEndPosition() performs correctly,
283 // even when GetNextAlignmentCore() is called
284 const unsigned int cigarDataOffset = alignment.SupportData.QueryNameLength;
285 uint32_t* cigarData = (uint32_t*)(allCharData.Buffer + cigarDataOffset);
287 alignment.CigarData.clear();
288 alignment.CigarData.reserve(alignment.SupportData.NumCigarOperations);
289 for ( unsigned int i = 0; i < alignment.SupportData.NumCigarOperations; ++i ) {
291 // swap endian-ness if necessary
292 if ( m_isBigEndian ) BamTools::SwapEndian_32(cigarData[i]);
294 // build CigarOp structure
295 op.Length = (cigarData[i] >> Constants::BAM_CIGAR_SHIFT);
296 op.Type = Constants::BAM_CIGAR_LOOKUP[ (cigarData[i] & Constants::BAM_CIGAR_MASK) ];
299 alignment.CigarData.push_back(op);
303 // return success/failure
304 return readCharDataOK;
307 // loads reference data from BAM file
308 bool BamReaderPrivate::LoadReferenceData(void) {
310 // get number of reference sequences
311 char buffer[sizeof(uint32_t)];
312 m_stream.Read(buffer, sizeof(uint32_t));
313 uint32_t numberRefSeqs = BamTools::UnpackUnsignedInt(buffer);
314 if ( m_isBigEndian ) BamTools::SwapEndian_32(numberRefSeqs);
315 m_references.reserve((int)numberRefSeqs);
317 // iterate over all references in header
318 for ( unsigned int i = 0; i != numberRefSeqs; ++i ) {
320 // get length of reference name
321 m_stream.Read(buffer, sizeof(uint32_t));
322 uint32_t refNameLength = BamTools::UnpackUnsignedInt(buffer);
323 if ( m_isBigEndian ) BamTools::SwapEndian_32(refNameLength);
324 RaiiBuffer refName(refNameLength);
326 // get reference name and reference sequence length
327 m_stream.Read(refName.Buffer, refNameLength);
328 m_stream.Read(buffer, sizeof(int32_t));
329 int32_t refLength = BamTools::UnpackSignedInt(buffer);
330 if ( m_isBigEndian ) BamTools::SwapEndian_32(refLength);
332 // store data for reference
334 aReference.RefName = (string)((const char*)refName.Buffer);
335 aReference.RefLength = refLength;
336 m_references.push_back(aReference);
343 bool BamReaderPrivate::LocateIndex(const BamIndex::IndexType& preferredType) {
345 if ( m_randomAccessController.LocateIndex(this, preferredType) )
348 const string bracError = m_randomAccessController.GetErrorString();
349 const string message = string("could not locate index: \n\t") + bracError;
350 SetErrorString("BamReader::LocateIndex", message);
355 // opens BAM file (and index)
356 bool BamReaderPrivate::Open(const string& filename) {
362 // make sure we're starting with fresh state
366 m_stream.Open(filename, "rb");
373 // store filename & offset of first alignment
374 m_filename = filename;
375 m_alignmentsBeginOffset = m_stream.Tell();
380 } catch ( BamException& e ) {
381 const string error = e.what();
382 const string message = string("could not open file: ") + filename +
384 SetErrorString("BamReader::Open", message);
388 // return success/failure
392 bool BamReaderPrivate::OpenIndex(const std::string& indexFilename) {
394 if ( m_randomAccessController.OpenIndex(indexFilename, this) )
397 const string bracError = m_randomAccessController.GetErrorString();
398 const string message = string("could not open index: \n\t") + bracError;
399 SetErrorString("BamReader::OpenIndex", message);
404 // returns BAM file pointer to beginning of alignment data
405 bool BamReaderPrivate::Rewind(void) {
408 m_randomAccessController.ClearRegion();
410 // return status of seeking back to first alignment
411 if ( Seek(m_alignmentsBeginOffset) )
414 const string currentError = m_errorString;
415 const string message = string("could not rewind: \n\t") + currentError;
416 SetErrorString("BamReader::Rewind", message);
421 bool BamReaderPrivate::Seek(const int64_t& position) {
423 // skip if BAM file not open
425 SetErrorString("BamReader::Seek", "cannot seek on unopened BAM file");
430 m_stream.Seek(position);
433 catch ( BamException& e ) {
434 const string streamError = e.what();
435 const string message = string("could not seek in BAM file: \n\t") + streamError;
436 SetErrorString("BamReader::Seek", message);
441 void BamReaderPrivate::SetErrorString(const string& where, const string& what) {
442 static const string SEPARATOR = ": ";
443 m_errorString = where + SEPARATOR + what;
446 void BamReaderPrivate::SetIndex(BamIndex* index) {
447 m_randomAccessController.SetIndex(index);
450 // change the index caching behavior
451 void BamReaderPrivate::SetIndexCacheMode(const BamIndex::IndexCacheMode& mode) {
452 m_randomAccessController.SetIndexCacheMode(mode);
455 // sets current region & attempts to jump to it
456 // returns success/failure
457 bool BamReaderPrivate::SetRegion(const BamRegion& region) {
459 if ( m_randomAccessController.SetRegion(region, m_references.size()) )
462 const string bracError = m_randomAccessController.GetErrorString();
463 const string message = string("could not set region: \n\t") + bracError;
464 SetErrorString("BamReader::SetRegion", message);
469 int64_t BamReaderPrivate::Tell(void) const {
470 return m_stream.Tell();