initial commit, 4.5 stable

thirdparty/icu4c/common/unicode/bytestriebuilder.h

@@ -0,0 +1,193 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+*******************************************************************************
+*   Copyright (C) 2010-2016, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*******************************************************************************
+*   file name:  bytestriebuilder.h
+*   encoding:   UTF-8
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2010sep25
+*   created by: Markus W. Scherer
+*/
+
+/**
+ * \file
+ * \brief C++ API: Builder for icu::BytesTrie
+ */
+
+#ifndef __BYTESTRIEBUILDER_H__
+#define __BYTESTRIEBUILDER_H__
+
+#include "unicode/utypes.h"
+
+#if U_SHOW_CPLUSPLUS_API
+
+#include "unicode/bytestrie.h"
+#include "unicode/stringpiece.h"
+#include "unicode/stringtriebuilder.h"
+
+class BytesTrieTest;
+
+U_NAMESPACE_BEGIN
+
+class BytesTrieElement;
+class CharString;
+/**
+ * Builder class for BytesTrie.
+ *
+ * This class is not intended for public subclassing.
+ * @stable ICU 4.8
+ */
+class U_COMMON_API BytesTrieBuilder : public StringTrieBuilder {
+public:
+    /**
+     * Constructs an empty builder.
+     * @param errorCode Standard ICU error code.
+     * @stable ICU 4.8
+     */
+    BytesTrieBuilder(UErrorCode &errorCode);
+
+    /**
+     * Destructor.
+     * @stable ICU 4.8
+     */
+    virtual ~BytesTrieBuilder();
+
+    /**
+     * Adds a (byte sequence, value) pair.
+     * The byte sequence must be unique.
+     * The bytes will be copied; the builder does not keep
+     * a reference to the input StringPiece or its data().
+     * @param s The input byte sequence.
+     * @param value The value associated with this byte sequence.
+     * @param errorCode Standard ICU error code. Its input value must
+     *                  pass the U_SUCCESS() test, or else the function returns
+     *                  immediately. Check for U_FAILURE() on output or use with
+     *                  function chaining. (See User Guide for details.)
+     * @return *this
+     * @stable ICU 4.8
+     */
+    BytesTrieBuilder &add(StringPiece s, int32_t value, UErrorCode &errorCode);
+
+    /**
+     * Builds a BytesTrie for the add()ed data.
+     * Once built, no further data can be add()ed until clear() is called.
+     *
+     * A BytesTrie cannot be empty. At least one (byte sequence, value) pair
+     * must have been add()ed.
+     *
+     * This method passes ownership of the builder's internal result array to the new trie object.
+     * Another call to any build() variant will re-serialize the trie.
+     * After clear() has been called, a new array will be used as well.
+     * @param buildOption Build option, see UStringTrieBuildOption.
+     * @param errorCode Standard ICU error code. Its input value must
+     *                  pass the U_SUCCESS() test, or else the function returns
+     *                  immediately. Check for U_FAILURE() on output or use with
+     *                  function chaining. (See User Guide for details.)
+     * @return A new BytesTrie for the add()ed data.
+     * @stable ICU 4.8
+     */
+    BytesTrie *build(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
+
+    /**
+     * Builds a BytesTrie for the add()ed data and byte-serializes it.
+     * Once built, no further data can be add()ed until clear() is called.
+     *
+     * A BytesTrie cannot be empty. At least one (byte sequence, value) pair
+     * must have been add()ed.
+     *
+     * Multiple calls to buildStringPiece() return StringPieces referring to the
+     * builder's same byte array, without rebuilding.
+     * If buildStringPiece() is called after build(), the trie will be
+     * re-serialized into a new array (because build() passes on ownership).
+     * If build() is called after buildStringPiece(), the trie object returned
+     * by build() will become the owner of the underlying string for the
+     * previously returned StringPiece.
+     * After clear() has been called, a new array will be used as well.
+     * @param buildOption Build option, see UStringTrieBuildOption.
+     * @param errorCode Standard ICU error code. Its input value must
+     *                  pass the U_SUCCESS() test, or else the function returns
+     *                  immediately. Check for U_FAILURE() on output or use with
+     *                  function chaining. (See User Guide for details.)
+     * @return A StringPiece which refers to the byte-serialized BytesTrie for the add()ed data.
+     * @stable ICU 4.8
+     */
+    StringPiece buildStringPiece(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
+
+    /**
+     * Removes all (byte sequence, value) pairs.
+     * New data can then be add()ed and a new trie can be built.
+     * @return *this
+     * @stable ICU 4.8
+     */
+    BytesTrieBuilder &clear();
+
+private:
+    friend class ::BytesTrieTest;
+
+    BytesTrieBuilder(const BytesTrieBuilder &other) = delete;  // no copy constructor
+    BytesTrieBuilder &operator=(const BytesTrieBuilder &other) = delete;  // no assignment operator
+
+    void buildBytes(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
+
+    virtual int32_t getElementStringLength(int32_t i) const override;
+    virtual char16_t getElementUnit(int32_t i, int32_t byteIndex) const override;
+    virtual int32_t getElementValue(int32_t i) const override;
+
+    virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t byteIndex) const override;
+
+    virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t byteIndex) const override;
+    virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t byteIndex, int32_t count) const override;
+    virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t byteIndex, char16_t byte) const override;
+
+    virtual UBool matchNodesCanHaveValues() const override { return false; }
+
+    virtual int32_t getMaxBranchLinearSubNodeLength() const override { return BytesTrie::kMaxBranchLinearSubNodeLength; }
+    virtual int32_t getMinLinearMatch() const override { return BytesTrie::kMinLinearMatch; }
+    virtual int32_t getMaxLinearMatchLength() const override { return BytesTrie::kMaxLinearMatchLength; }
+
+    /**
+     * @internal (private)
+     */
+    class BTLinearMatchNode : public LinearMatchNode {
+    public:
+        BTLinearMatchNode(const char *units, int32_t len, Node *nextNode);
+        virtual bool operator==(const Node &other) const override;
+        virtual void write(StringTrieBuilder &builder) override;
+    private:
+        const char *s;
+    };
+    
+    virtual Node *createLinearMatchNode(int32_t i, int32_t byteIndex, int32_t length,
+                                        Node *nextNode) const override;
+
+    UBool ensureCapacity(int32_t length);
+    virtual int32_t write(int32_t byte) override;
+    int32_t write(const char *b, int32_t length);
+    virtual int32_t writeElementUnits(int32_t i, int32_t byteIndex, int32_t length) override;
+    virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal) override;
+    virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node) override;
+    virtual int32_t writeDeltaTo(int32_t jumpTarget) override;
+    static int32_t internalEncodeDelta(int32_t i, char intBytes[]);
+
+    CharString *strings;  // Pointer not object so we need not #include internal charstr.h.
+    BytesTrieElement *elements;
+    int32_t elementsCapacity;
+    int32_t elementsLength;
+
+    // Byte serialization of the trie.
+    // Grows from the back: bytesLength measures from the end of the buffer!
+    char *bytes;
+    int32_t bytesCapacity;
+    int32_t bytesLength;
+};
+
+U_NAMESPACE_END
+
+#endif /* U_SHOW_CPLUSPLUS_API */
+
+#endif  // __BYTESTRIEBUILDER_H__