Golang C.DECREF类(方法)实例源码

// This will need to be a bit more generic,
// but for testing this will work fine.
func (search *Search) GetSearcher() IndexReader {
	idxLocation := cb_newf(search.Location)
	search.lucySearcher = C.LucyIxSearcherNew(idxLocation)
	C.DECREF(idxLocation)
	return func(q string, field string, offset, limit uint) (uint, []string) {
		query := cb_new_from_utf8(q)
		getField := cb_newf(field)
		hits := C.LucyIxSearcherHits(search.lucySearcher, query, C.uint32_t(offset), C.uint32_t(limit), nil)
		totalNumHits := uint(C.LucyHitsTotal(hits))
		requestedNumHits := minUInt(limit, totalNumHits)
		results := make([]string, requestedNumHits)
		var hit *C.LucyHitDoc
		for i := uint(0); i < requestedNumHits; i++ {
			hit = C.LucyHitsNext(hits)
			if hit == nil {
				break
			}
			value_cb := C.LucyHitDocExtract(hit, getField, nil) // do i need to free this
			value := cb_ptr2char(value_cb)                      // do i need to free this
			results[i] = C.GoString(value)
			C.DECREF(hit)
		}
		C.DECREF(query)
		C.DECREF(getField)
		C.DECREF(hits)
		return totalNumHits, results
	}
}

func NewAnalyzer(language string, stemTerms bool) *Analyzer {
	lang := cb_newf(language)
	defer C.DECREF((*C.cfish_Obj)(lang))

	// non-stemming analyzer still does case-folding (normalizing) and tokenizing
	var analyzer *Analyzer
	if stemTerms {
		// see https://lucy.apache.org/docs/test/Lucy/Docs/Tutorial/Analysis.html
		analyzer = &Analyzer{Language: language, lucyAnalyzer: (*C.lucy_Analyzer)(C.LucyEasyAnalyzerNew(lang))}
	} else {
		tokenizer := C.LucyStandardTokenizerNew()
		normalizer := C.LucyNormalizerNew(nil, (C.bool)(true), (C.bool)(false))
		analyzers := C.CFishVArrayNew((C.uint32_t)(2))

		//defer C.DECREF(tokenizer) get a segfault if i do this..
		//defer C.DECREF(normalizer) get a segfault if i do this..
		defer C.DECREF((*C.cfish_Obj)(analyzers)) // this works, however

		// have to push the tokenizer before the normalizer - otherwise
		// bad bad bad bad bad bad things will happen.
		C.CFishVArrayPush(analyzers, (*C.cfish_Obj)(tokenizer))
		C.CFishVArrayPush(analyzers, (*C.cfish_Obj)(normalizer))
		analyzer = &Analyzer{Language: language, lucyAnalyzer: (*C.lucy_Analyzer)(C.LucyPolyAnalyzerNew(lang, analyzers))}
	}
	runtime.SetFinalizer(analyzer, freeAnalyzer)
	return analyzer
}

func (schema *Schema) createLucySchema() {
	lucySchema := C.LucySchemaNew()
	for _, item := range schema.PlanItems {
		var specType *C.CFishObj
		if item.Type == FullTextType {
			var language *C.CFishCharBuf
			if item.Options != nil && item.Options.Language != "" {
				language = cb_newf(item.Options.Language)
			} else {
				language = cb_newf("en")
			}
			analyzer := C.LucyEasyAnalyzerNew(language)
			specType = C.LucyFullTextTypeNew(analyzer)
			// TODO: come up with a better way to handle options.
			// This isn't very friendly.
			if item.Options != nil {
				specType = C.LucyFullTextTypeInitOptions(specType, analyzer,
					(C.float)(item.Options.Boost),
					(C.bool)(item.Options.Indexed),
					(C.bool)(item.Options.Stored),
					(C.bool)(item.Options.Sortable),
					(C.bool)(item.Options.Highlightable),
				)
			}
			C.DECREF(language)
			C.DECREF(analyzer)
		} else if item.Type == StringType {
			specType = C.LucyStringTypeNew()
			if item.Options != nil {
				specType = C.LucyStringTypeInitOptions(specType,
					(C.float)(item.Options.Boost),
					(C.bool)(item.Options.Indexed),
					(C.bool)(item.Options.Stored),
					(C.bool)(item.Options.Sortable),
				)
			}
		} else if item.Type == BlobType {
			isStored := (C.bool)(false)
			if item.Options != nil && item.Options.Stored {
				isStored = (C.bool)(true)
			}
			specType = C.LucyBlobTypeNew(isStored)
			// need to send []cfish_byte castable value
			panic("BlobType not supported yet")
		} else {
			panic("Type not supported yet")
		}
		fieldName := cb_newf(item.Field)
		C.LucySchemaSpecField(lucySchema, fieldName, specType)
		C.DECREF(fieldName)
		C.DECREF(specType)
	}
	schema.lucySchema = lucySchema
}

func (ixWriter *IndexWriter) AddDoc(doc Document) {
	lDoc := C.LucyDocNew(nil, 0) // Are these sane defaults?
	for k, v := range doc {
		name := cb_newf(k)
		value := cb_new_from_utf8(v)
		C.LucyDocStore(lDoc, name, value)
		C.DECREF(name)
		C.DECREF(value)
	}
	C.LucyIndexerAddDoc(ixWriter.lucyIndexer, lDoc, 1.0) // Is 1.0 a sane default?
	C.DECREF(lDoc)
}

// encodeTuple translates a Go array to a Python object.
func encodeTuple(array []interface{}) (pyTuple *C.PyObject, err error) {
	if len(array) == 0 {
		pyTuple = pyEmptyTuple
		C.INCREF(pyTuple)
	} else {
		pyTuple = C.PyTuple_New(C.Py_ssize_t(len(array)))

		var ok bool

		defer func() {
			if !ok {
				C.DECREF(pyTuple)
				pyTuple = nil
			}
		}()

		for i, item := range array {
			var pyItem *C.PyObject

			if pyItem, err = encode(item); err != nil {
				return
			}

			C.Tuple_SET_ITEM(pyTuple, C.Py_ssize_t(i), pyItem)
		}

		ok = true
	}

	return
}

func (ixWriter *IndexWriter) Close() {
	// Should this be here or in Commit?
	if ixWriter.lucyIndexer != nil {
		C.DECREF(ixWriter.lucyIndexer)
		ixWriter.lucyIndexer = nil
	}
}

// getError translates the current Python exception to a Go error, and clears
// the Python exception state.
func getError() error {
	var (
		pyType  *C.PyObject
		pyValue *C.PyObject
		pyTrace *C.PyObject
	)

	C.PyErr_Fetch(&pyType, &pyValue, &pyTrace)

	defer C.DECREF(pyType)
	defer C.DECREF(pyValue)
	defer xDECREF(pyTrace)

	C.PyErr_Clear()

	return fmt.Errorf("Python: %s", stringify(pyValue))
}

func (schema *Schema) AddField(field *Field) {
	schema.Fields = append(schema.Fields, field)
	var specType *C.lucy_FieldType
	defer C.DECREF((*C.cfish_Obj)(specType))
	name := cb_newf(field.Name)
	defer C.DECREF((*C.cfish_Obj)(name))

	switch field.IndexType {
	case FullTextType:
		specType = fullTextSpecType(field)
	case StringType:
		specType = stringSpecType(field)
	default:
		panic("Specified IndexType not supported yet")
	}
	C.LucySchemaSpecField(schema.lucySchema, name, specType)
}

func (index *Index) GetIndexWriter(flags IndexOpenFlags) IndexWriter {
	idxLocation := cb_newf(index.Location)
	index.lucyIndexer = C.LucyIndexerNew(index.Schema.lucySchema, idxLocation, nil, C.int32_t(flags))
	C.DECREF(idxLocation)
	return func(ixValueColumns ...*IndexValueColumn) {
		doc := C.LucyDocNew(nil, 0)
		for _, ixColumn := range ixValueColumns {
			fieldName := cb_newf(ixColumn.Field)
			fieldValue := cb_new_from_utf8(ixColumn.Value)
			C.LucyDocStore(doc, fieldName, fieldValue)
			C.DECREF(fieldName)
			C.DECREF(fieldValue)
		}
		C.LucyIndexerAddDoc(index.lucyIndexer, doc, 1.0)
		C.DECREF(doc)
	}
}

func call(pyObject *C.PyObject, name string, args []interface{}) (pyType C.int, pyResult *C.PyObject, err error) {
	pyMember, err := getAttr(pyObject, name)
	if err != nil {
		return
	}
	defer C.DECREF(pyMember)

	return invoke(pyMember, args)
}

func encodeDictItem(pyDict *C.PyObject, key, value interface{}) (err error) {
	pyKey, err := encode(key)
	if err != nil {
		return
	}
	defer C.DECREF(pyKey)

	pyValue, err := encode(value)
	if err != nil {
		return
	}
	defer C.DECREF(pyValue)

	if C.PyDict_SetItem(pyDict, pyKey, pyValue) < 0 {
		err = getError()
	}
	return
}

func (ixReader *IndexReader) Search(query *Query, offset, limit uint, idField string, contentField string, includeMatchedTerms bool) (uint, []*SearchResult) {
	// Should probably have some sort
	// of `Results` object/iterator so that we don't have to specify
	// offset/limit and where I can attach matched terms to the result.
	lIdField, lContentField := cb_newf(idField), cb_newf(contentField) // total hack, need to return more than one field
	defer C.DECREF(lIdField)
	defer C.DECREF(lContentField)
	hits := C.LucyIxSearcherHits(ixReader.lucySearcher, query.lucyQuery, C.uint32_t(offset), C.uint32_t(limit), nil)
	defer C.DECREF(hits)
	totalNumHits := uint(C.LucyHitsTotal(hits))
	num2Return := minUInt(limit, totalNumHits)
	results := make([]*SearchResult, num2Return)
	var hit *C.LucyHitDoc
	compiler := C.LucyQueryMakeCompiler(query.lucyQuery, ixReader.lucySearcher, 1.0, false)
	defer C.DECREF(compiler)

	matchedTerms := func(docId C.int32_t, result *SearchResult) {
		docVec := C.LucyIxSearchFetchDocVec(ixReader.lucySearcher, docId)
		defer C.DECREF(docVec)
		spans := C.LucyCompilerHighlightSpans(compiler, ixReader.lucySearcher, docVec, lContentField)
		defer C.DECREF(spans)
		spanCnt := C.VaGetSize(spans)
		if spanCnt == 0 {
			// should never get here, but just in case...
			return
		}
		result.MatchedTerms = make([]string, spanCnt)
		var i C.uint32_t
		for i = 0; i < spanCnt; i++ {
			span := C.VaFetch(spans, i)
			offset := C.LucySpanGetOffset(span)
			length := C.LucySpanGetLength(span)
			result.MatchedTerms[i] = string([]rune(result.Text)[offset : offset+length])
		}
		// make terms unique?
		result.MatchedTerms = set(result.MatchedTerms)
	}
	var i uint
	for i = 0; i < num2Return; i++ {
		hit = C.LucyHitsNext(hits)
		if hit == nil {
			break
		}
		docId := C.LucyHitDocGetDocId(hit)
		contentValue := cb_ptr2char(C.LucyHitDocExtract(hit, lContentField, nil)) // do i need to free this
		idValue := cb_ptr2char(C.LucyHitDocExtract(hit, lIdField, nil))           // do i need to free this
		results[i] = &SearchResult{
			Id:    C.GoString(idValue),
			Text:  C.GoString(contentValue),
			Score: float32(C.LucyHitDocGetScore(hit)),
		}
		if includeMatchedTerms {
			matchedTerms(docId, results[i])
		}
		C.DECREF(hit)
	}
	return totalNumHits, results
}

func (index *Index) NewIndexReader() *IndexReader {
	ixLocation := cb_newf(index.Path)
	defer C.DECREF(ixLocation)
	ixReader := &IndexReader{
		Index:        index,
		lucySearcher: C.LucyIxSearcherNew(ixLocation),
	}
	runtime.SetFinalizer(ixReader, freeIndexReader)
	return ixReader
}

func stringify(pyObject *C.PyObject) (s string) {
	if pyResult := C.PyObject_Str(pyObject); pyResult != nil {
		defer C.DECREF(pyResult)

		if cString := C.PyString_AsString(pyResult); cString != nil {
			s = C.GoString(cString)
		}
	}

	C.PyErr_Clear()
	return
}

func (ixReader *IndexReader) ParseQuery(queryStr string, stemTerms bool) *Query {
	lucySchema := C.LucyIxSearcherGetSchema(ixReader.lucySearcher)
	language := cb_newf("en") // should be configurable
	defer C.DECREF(language)

	var analyzer *C.LucyAnalyzer
	if stemTerms {
		analyzer = C.LucyEasyAnalyzerNew(language)
	} else {
		// this seems rather verbose for just creating an analyzer..
		tokenizer := C.LucyStandardTokenizerNew()
		normalizer := C.LucyNormalizerNew(nil, (C.bool)(true), (C.bool)(false))
		analyzers := C.CFishVArrayNew((C.uint32_t)(2))

		//defer C.DECREF(tokenizer) get a segfault if i do this..
		//defer C.DECREF(normalizer) get a segfault if i do this..
		defer C.DECREF(analyzers) // this works, however

		C.CFishVArrayPush(analyzers, tokenizer)
		C.CFishVArrayPush(analyzers, normalizer)
		analyzer = C.LucyPolyAnalyzerNew(language, analyzers)
	}

	defer C.DECREF(analyzer)
	qp := C.LucyQParserNew(
		lucySchema,
		analyzer,                          //should this be configurable?
		cb_newf("AND"),                    // should be configurable
		C.LucySchemaAllFields(lucySchema), // should be configurable
	)
	defer C.DECREF(qp)
	qs := cb_new_from_utf8(queryStr)
	defer C.DECREF(qs)
	query := &Query{
		QueryStr:  queryStr,
		lucyQuery: C.LucyQParserParse(qp, qs),
	}
	runtime.SetFinalizer(query, freeQuery)
	return query
}

func (o *object) Item(t *Thread, i int) (item Object, err error) {
	t.execute(func() {
		pyItem := C.PySequence_GetItem(o.pyObject, C.Py_ssize_t(i))
		if pyItem == nil {
			err = getError()
			return
		}
		defer C.DECREF(pyItem)

		item = newObject(pyItem)
	})
	return
}

func (o *object) ItemValue(t *Thread, i int) (item interface{}, err error) {
	t.execute(func() {
		pyItem := C.PySequence_GetItem(o.pyObject, C.Py_ssize_t(i))
		if pyItem == nil {
			err = getError()
			return
		}
		defer C.DECREF(pyItem)

		item, err = decode(pyItem)
	})
	return
}

func (o *object) AttrValue(t *Thread, name string) (attr interface{}, err error) {
	t.execute(func() {
		var pyAttr *C.PyObject

		pyAttr, err = getAttr(o.pyObject, name)
		if err != nil {
			return
		}
		defer C.DECREF(pyAttr)

		attr, err = decode(pyAttr)
	})
	return
}

func (o *object) Attr(t *Thread, name string) (attr Object, err error) {
	t.execute(func() {
		var pyAttr *C.PyObject

		pyAttr, err = getAttr(o.pyObject, name)
		if err != nil {
			return
		}
		defer C.DECREF(pyAttr)

		attr = newObject(pyAttr)
	})
	return
}

// Import a Python module.
func Import(t *Thread, name string) (module Object, err error) {
	cName := C.CString(name)
	defer C.free(unsafe.Pointer(cName))

	t.execute(func() {
		pyModule := C.PyImport_ImportModule(cName)
		if pyModule == nil {
			err = getError()
			return
		}
		defer C.DECREF(pyModule)

		module = newObject(pyModule)
	})
	return
}