From 381c12df20f0113c141c3590e21fdae405f57853 Mon Sep 17 00:00:00 2001 From: Keisuke Kuroyanagi Date: Fri, 16 Aug 2013 16:42:17 +0900 Subject: [PATCH] Move methods in BinaryFormat to PatriciaTriePolicy. Bug: 6669677 Change-Id: Ic9bc03a9d8ec789281d83d4b9e58042a083c3ba1 --- .../policyimpl/dictionary/binary_format.h | 470 ------------------ .../dictionary/patricia_trie_policy.cpp | 265 +++++++++- 2 files changed, 260 insertions(+), 475 deletions(-) delete mode 100644 native/jni/src/suggest/policyimpl/dictionary/binary_format.h diff --git a/native/jni/src/suggest/policyimpl/dictionary/binary_format.h b/native/jni/src/suggest/policyimpl/dictionary/binary_format.h deleted file mode 100644 index 23f4c7fec..000000000 --- a/native/jni/src/suggest/policyimpl/dictionary/binary_format.h +++ /dev/null @@ -1,470 +0,0 @@ -/* - * Copyright (C) 2011 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#ifndef LATINIME_BINARY_FORMAT_H -#define LATINIME_BINARY_FORMAT_H - -#include - -#include "suggest/core/dictionary/probability_utils.h" -#include "utils/char_utils.h" - -namespace latinime { - -class BinaryFormat { - public: - // Mask and flags for children address type selection. - static const int MASK_GROUP_ADDRESS_TYPE = 0xC0; - - // Flag for single/multiple char group - static const int FLAG_HAS_MULTIPLE_CHARS = 0x20; - - // Flag for terminal groups - static const int FLAG_IS_TERMINAL = 0x10; - - // Flag for shortcut targets presence - static const int FLAG_HAS_SHORTCUT_TARGETS = 0x08; - // Flag for bigram presence - static const int FLAG_HAS_BIGRAMS = 0x04; - // Flag for non-words (typically, shortcut only entries) - static const int FLAG_IS_NOT_A_WORD = 0x02; - // Flag for blacklist - static const int FLAG_IS_BLACKLISTED = 0x01; - - // Attribute (bigram/shortcut) related flags: - // Flag for presence of more attributes - static const int FLAG_ATTRIBUTE_HAS_NEXT = 0x80; - // Flag for sign of offset. If this flag is set, the offset value must be negated. - static const int FLAG_ATTRIBUTE_OFFSET_NEGATIVE = 0x40; - - // Mask for attribute probability, stored on 4 bits inside the flags byte. - static const int MASK_ATTRIBUTE_PROBABILITY = 0x0F; - - // Mask and flags for attribute address type selection. - static const int MASK_ATTRIBUTE_ADDRESS_TYPE = 0x30; - - static int getGroupCountAndForwardPointer(const uint8_t *const dict, int *pos); - static uint8_t getFlagsAndForwardPointer(const uint8_t *const dict, int *pos); - static int getCodePointAndForwardPointer(const uint8_t *const dict, int *pos); - static int readProbabilityWithoutMovingPointer(const uint8_t *const dict, const int pos); - static int skipOtherCharacters(const uint8_t *const dict, const int pos); - static int skipChildrenPosition(const uint8_t flags, const int pos); - static int skipProbability(const uint8_t flags, const int pos); - static int skipShortcuts(const uint8_t *const dict, const uint8_t flags, const int pos); - static int skipChildrenPosAndAttributes(const uint8_t *const dict, const uint8_t flags, - const int pos); - static int readChildrenPosition(const uint8_t *const dict, const uint8_t flags, const int pos); - static bool hasChildrenInFlags(const uint8_t flags); - static int getTerminalPosition(const uint8_t *const root, const int *const inWord, - const int length, const bool forceLowerCaseSearch); - static int getCodePointsAndProbabilityAndReturnCodePointCount( - const uint8_t *const root, const int nodePos, const int maxCodePointCount, - int *const outCodePoints, int *const outUnigramProbability); - - private: - DISALLOW_IMPLICIT_CONSTRUCTORS(BinaryFormat); - - static const int FLAG_GROUP_ADDRESS_TYPE_NOADDRESS = 0x00; - static const int FLAG_GROUP_ADDRESS_TYPE_ONEBYTE = 0x40; - static const int FLAG_GROUP_ADDRESS_TYPE_TWOBYTES = 0x80; - static const int FLAG_GROUP_ADDRESS_TYPE_THREEBYTES = 0xC0; - static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE = 0x10; - static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES = 0x20; - static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES = 0x30; - - static const int CHARACTER_ARRAY_TERMINATOR_SIZE = 1; - static const int MINIMAL_ONE_BYTE_CHARACTER_VALUE = 0x20; - static const int CHARACTER_ARRAY_TERMINATOR = 0x1F; - static const int MULTIPLE_BYTE_CHARACTER_ADDITIONAL_SIZE = 2; - static const int NO_FLAGS = 0; - static int skipAllAttributes(const uint8_t *const dict, const uint8_t flags, const int pos); - static int skipBigrams(const uint8_t *const dict, const uint8_t flags, const int pos); -}; - -AK_FORCE_INLINE int BinaryFormat::getGroupCountAndForwardPointer(const uint8_t *const dict, - int *pos) { - const int msb = dict[(*pos)++]; - if (msb < 0x80) return msb; - return ((msb & 0x7F) << 8) | dict[(*pos)++]; -} - -inline uint8_t BinaryFormat::getFlagsAndForwardPointer(const uint8_t *const dict, int *pos) { - return dict[(*pos)++]; -} - -AK_FORCE_INLINE int BinaryFormat::getCodePointAndForwardPointer(const uint8_t *const dict, - int *pos) { - const int origin = *pos; - const int codePoint = dict[origin]; - if (codePoint < MINIMAL_ONE_BYTE_CHARACTER_VALUE) { - if (codePoint == CHARACTER_ARRAY_TERMINATOR) { - *pos = origin + 1; - return NOT_A_CODE_POINT; - } else { - *pos = origin + 3; - const int char_1 = codePoint << 16; - const int char_2 = char_1 + (dict[origin + 1] << 8); - return char_2 + dict[origin + 2]; - } - } else { - *pos = origin + 1; - return codePoint; - } -} - -inline int BinaryFormat::readProbabilityWithoutMovingPointer(const uint8_t *const dict, - const int pos) { - return dict[pos]; -} - -AK_FORCE_INLINE int BinaryFormat::skipOtherCharacters(const uint8_t *const dict, const int pos) { - int currentPos = pos; - int character = dict[currentPos++]; - while (CHARACTER_ARRAY_TERMINATOR != character) { - if (character < MINIMAL_ONE_BYTE_CHARACTER_VALUE) { - currentPos += MULTIPLE_BYTE_CHARACTER_ADDITIONAL_SIZE; - } - character = dict[currentPos++]; - } - return currentPos; -} - -static inline int attributeAddressSize(const uint8_t flags) { - static const int ATTRIBUTE_ADDRESS_SHIFT = 4; - return (flags & BinaryFormat::MASK_ATTRIBUTE_ADDRESS_TYPE) >> ATTRIBUTE_ADDRESS_SHIFT; - /* Note: this is a value-dependant optimization of what may probably be - more readably written this way: - switch (flags * BinaryFormat::MASK_ATTRIBUTE_ADDRESS_TYPE) { - case FLAG_ATTRIBUTE_ADDRESS_TYPE_ONEBYTE: return 1; - case FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES: return 2; - case FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTE: return 3; - default: return 0; - } - */ -} - -static AK_FORCE_INLINE int skipExistingBigrams(const uint8_t *const dict, const int pos) { - int currentPos = pos; - uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(dict, ¤tPos); - while (flags & BinaryFormat::FLAG_ATTRIBUTE_HAS_NEXT) { - currentPos += attributeAddressSize(flags); - flags = BinaryFormat::getFlagsAndForwardPointer(dict, ¤tPos); - } - currentPos += attributeAddressSize(flags); - return currentPos; -} - -static inline int childrenAddressSize(const uint8_t flags) { - static const int CHILDREN_ADDRESS_SHIFT = 6; - return (BinaryFormat::MASK_GROUP_ADDRESS_TYPE & flags) >> CHILDREN_ADDRESS_SHIFT; - /* See the note in attributeAddressSize. The same applies here */ -} - -static AK_FORCE_INLINE int shortcutByteSize(const uint8_t *const dict, const int pos) { - return (static_cast(dict[pos] << 8)) + (dict[pos + 1]); -} - -inline int BinaryFormat::skipChildrenPosition(const uint8_t flags, const int pos) { - return pos + childrenAddressSize(flags); -} - -inline int BinaryFormat::skipProbability(const uint8_t flags, const int pos) { - return FLAG_IS_TERMINAL & flags ? pos + 1 : pos; -} - -AK_FORCE_INLINE int BinaryFormat::skipShortcuts(const uint8_t *const dict, const uint8_t flags, - const int pos) { - if (FLAG_HAS_SHORTCUT_TARGETS & flags) { - return pos + shortcutByteSize(dict, pos); - } else { - return pos; - } -} - -AK_FORCE_INLINE int BinaryFormat::skipBigrams(const uint8_t *const dict, const uint8_t flags, - const int pos) { - if (FLAG_HAS_BIGRAMS & flags) { - return skipExistingBigrams(dict, pos); - } else { - return pos; - } -} - -AK_FORCE_INLINE int BinaryFormat::skipAllAttributes(const uint8_t *const dict, const uint8_t flags, - const int pos) { - // This function skips all attributes: shortcuts and bigrams. - int newPos = pos; - newPos = skipShortcuts(dict, flags, newPos); - newPos = skipBigrams(dict, flags, newPos); - return newPos; -} - -AK_FORCE_INLINE int BinaryFormat::skipChildrenPosAndAttributes(const uint8_t *const dict, - const uint8_t flags, const int pos) { - int currentPos = pos; - currentPos = skipChildrenPosition(flags, currentPos); - currentPos = skipAllAttributes(dict, flags, currentPos); - return currentPos; -} - -AK_FORCE_INLINE int BinaryFormat::readChildrenPosition(const uint8_t *const dict, - const uint8_t flags, const int pos) { - int offset = 0; - switch (MASK_GROUP_ADDRESS_TYPE & flags) { - case FLAG_GROUP_ADDRESS_TYPE_ONEBYTE: - offset = dict[pos]; - break; - case FLAG_GROUP_ADDRESS_TYPE_TWOBYTES: - offset = dict[pos] << 8; - offset += dict[pos + 1]; - break; - case FLAG_GROUP_ADDRESS_TYPE_THREEBYTES: - offset = dict[pos] << 16; - offset += dict[pos + 1] << 8; - offset += dict[pos + 2]; - break; - default: - // If we come here, it means we asked for the children of a word with - // no children. - return -1; - } - return pos + offset; -} - -inline bool BinaryFormat::hasChildrenInFlags(const uint8_t flags) { - return (FLAG_GROUP_ADDRESS_TYPE_NOADDRESS != (MASK_GROUP_ADDRESS_TYPE & flags)); -} - -// This function gets the byte position of the last chargroup of the exact matching word in the -// dictionary. If no match is found, it returns NOT_A_VALID_WORD_POS. -AK_FORCE_INLINE int BinaryFormat::getTerminalPosition(const uint8_t *const root, - const int *const inWord, const int length, const bool forceLowerCaseSearch) { - int pos = 0; - int wordPos = 0; - - while (true) { - // If we already traversed the tree further than the word is long, there means - // there was no match (or we would have found it). - if (wordPos >= length) return NOT_A_VALID_WORD_POS; - int charGroupCount = BinaryFormat::getGroupCountAndForwardPointer(root, &pos); - const int wChar = forceLowerCaseSearch - ? CharUtils::toLowerCase(inWord[wordPos]) : inWord[wordPos]; - while (true) { - // If there are no more character groups in this node, it means we could not - // find a matching character for this depth, therefore there is no match. - if (0 >= charGroupCount) return NOT_A_VALID_WORD_POS; - const int charGroupPos = pos; - const uint8_t flags = BinaryFormat::getFlagsAndForwardPointer(root, &pos); - int character = BinaryFormat::getCodePointAndForwardPointer(root, &pos); - if (character == wChar) { - // This is the correct node. Only one character group may start with the same - // char within a node, so either we found our match in this node, or there is - // no match and we can return NOT_A_VALID_WORD_POS. So we will check all the - // characters in this character group indeed does match. - if (FLAG_HAS_MULTIPLE_CHARS & flags) { - character = BinaryFormat::getCodePointAndForwardPointer(root, &pos); - while (NOT_A_CODE_POINT != character) { - ++wordPos; - // If we shoot the length of the word we search for, or if we find a single - // character that does not match, as explained above, it means the word is - // not in the dictionary (by virtue of this chargroup being the only one to - // match the word on the first character, but not matching the whole word). - if (wordPos >= length) return NOT_A_VALID_WORD_POS; - if (inWord[wordPos] != character) return NOT_A_VALID_WORD_POS; - character = BinaryFormat::getCodePointAndForwardPointer(root, &pos); - } - } - // If we come here we know that so far, we do match. Either we are on a terminal - // and we match the length, in which case we found it, or we traverse children. - // If we don't match the length AND don't have children, then a word in the - // dictionary fully matches a prefix of the searched word but not the full word. - ++wordPos; - if (FLAG_IS_TERMINAL & flags) { - if (wordPos == length) { - return charGroupPos; - } - pos = BinaryFormat::skipProbability(FLAG_IS_TERMINAL, pos); - } - if (FLAG_GROUP_ADDRESS_TYPE_NOADDRESS == (MASK_GROUP_ADDRESS_TYPE & flags)) { - return NOT_A_VALID_WORD_POS; - } - // We have children and we are still shorter than the word we are searching for, so - // we need to traverse children. Put the pointer on the children position, and - // break - pos = BinaryFormat::readChildrenPosition(root, flags, pos); - break; - } else { - // This chargroup does not match, so skip the remaining part and go to the next. - if (FLAG_HAS_MULTIPLE_CHARS & flags) { - pos = BinaryFormat::skipOtherCharacters(root, pos); - } - pos = BinaryFormat::skipProbability(flags, pos); - pos = BinaryFormat::skipChildrenPosAndAttributes(root, flags, pos); - } - --charGroupCount; - } - } -} - -// This function searches for a terminal in the dictionary by its address. -// Due to the fact that words are ordered in the dictionary in a strict breadth-first order, -// it is possible to check for this with advantageous complexity. For each node, we search -// for groups with children and compare the children address with the address we look for. -// When we shoot the address we look for, it means the word we look for is in the children -// of the previous group. The only tricky part is the fact that if we arrive at the end of a -// node with the last group's children address still less than what we are searching for, we -// must descend the last group's children (for example, if the word we are searching for starts -// with a z, it's the last group of the root node, so all children addresses will be smaller -// than the address we look for, and we have to descend the z node). -/* Parameters : - * root: the dictionary buffer - * address: the byte position of the last chargroup of the word we are searching for (this is - * what is stored as the "bigram address" in each bigram) - * outword: an array to write the found word, with MAX_WORD_LENGTH size. - * outUnigramProbability: a pointer to an int to write the probability into. - * Return value : the length of the word, of 0 if the word was not found. - */ -AK_FORCE_INLINE int BinaryFormat::getCodePointsAndProbabilityAndReturnCodePointCount( - const uint8_t *const root, const int nodePos, const int maxCodePointCount, - int *const outCodePoints, int *const outUnigramProbability) { - int pos = 0; - int wordPos = 0; - - // One iteration of the outer loop iterates through nodes. As stated above, we will only - // traverse nodes that are actually a part of the terminal we are searching, so each time - // we enter this loop we are one depth level further than last time. - // The only reason we count nodes is because we want to reduce the probability of infinite - // looping in case there is a bug. Since we know there is an upper bound to the depth we are - // supposed to traverse, it does not hurt to count iterations. - for (int loopCount = maxCodePointCount; loopCount > 0; --loopCount) { - int lastCandidateGroupPos = 0; - // Let's loop through char groups in this node searching for either the terminal - // or one of its ascendants. - for (int charGroupCount = getGroupCountAndForwardPointer(root, &pos); charGroupCount > 0; - --charGroupCount) { - const int startPos = pos; - const uint8_t flags = getFlagsAndForwardPointer(root, &pos); - const int character = getCodePointAndForwardPointer(root, &pos); - if (nodePos == startPos) { - // We found the address. Copy the rest of the word in the buffer and return - // the length. - outCodePoints[wordPos] = character; - if (FLAG_HAS_MULTIPLE_CHARS & flags) { - int nextChar = getCodePointAndForwardPointer(root, &pos); - // We count chars in order to avoid infinite loops if the file is broken or - // if there is some other bug - int charCount = maxCodePointCount; - while (NOT_A_CODE_POINT != nextChar && --charCount > 0) { - outCodePoints[++wordPos] = nextChar; - nextChar = getCodePointAndForwardPointer(root, &pos); - } - } - *outUnigramProbability = readProbabilityWithoutMovingPointer(root, pos); - return ++wordPos; - } - // We need to skip past this char group, so skip any remaining chars after the - // first and possibly the probability. - if (FLAG_HAS_MULTIPLE_CHARS & flags) { - pos = skipOtherCharacters(root, pos); - } - pos = skipProbability(flags, pos); - - // The fact that this group has children is very important. Since we already know - // that this group does not match, if it has no children we know it is irrelevant - // to what we are searching for. - const bool hasChildren = (FLAG_GROUP_ADDRESS_TYPE_NOADDRESS != - (MASK_GROUP_ADDRESS_TYPE & flags)); - // We will write in `found' whether we have passed the children address we are - // searching for. For example if we search for "beer", the children of b are less - // than the address we are searching for and the children of c are greater. When we - // come here for c, we realize this is too big, and that we should descend b. - bool found; - if (hasChildren) { - // Here comes the tricky part. First, read the children position. - const int childrenPos = readChildrenPosition(root, flags, pos); - if (childrenPos > nodePos) { - // If the children pos is greater than address, it means the previous chargroup, - // which address is stored in lastCandidateGroupPos, was the right one. - found = true; - } else if (1 >= charGroupCount) { - // However if we are on the LAST group of this node, and we have NOT shot the - // address we should descend THIS node. So we trick the lastCandidateGroupPos - // so that we will descend this node, not the previous one. - lastCandidateGroupPos = startPos; - found = true; - } else { - // Else, we should continue looking. - found = false; - } - } else { - // Even if we don't have children here, we could still be on the last group of this - // node. If this is the case, we should descend the last group that had children, - // and their address is already in lastCandidateGroup. - found = (1 >= charGroupCount); - } - - if (found) { - // Okay, we found the group we should descend. Its address is in - // the lastCandidateGroupPos variable, so we just re-read it. - if (0 != lastCandidateGroupPos) { - const uint8_t lastFlags = - getFlagsAndForwardPointer(root, &lastCandidateGroupPos); - const int lastChar = - getCodePointAndForwardPointer(root, &lastCandidateGroupPos); - // We copy all the characters in this group to the buffer - outCodePoints[wordPos] = lastChar; - if (FLAG_HAS_MULTIPLE_CHARS & lastFlags) { - int nextChar = getCodePointAndForwardPointer(root, &lastCandidateGroupPos); - int charCount = maxCodePointCount; - while (-1 != nextChar && --charCount > 0) { - outCodePoints[++wordPos] = nextChar; - nextChar = getCodePointAndForwardPointer(root, &lastCandidateGroupPos); - } - } - ++wordPos; - // Now we only need to branch to the children address. Skip the probability if - // it's there, read pos, and break to resume the search at pos. - lastCandidateGroupPos = skipProbability(lastFlags, lastCandidateGroupPos); - pos = readChildrenPosition(root, lastFlags, lastCandidateGroupPos); - break; - } else { - // Here is a little tricky part: we come here if we found out that all children - // addresses in this group are bigger than the address we are searching for. - // Should we conclude the word is not in the dictionary? No! It could still be - // one of the remaining chargroups in this node, so we have to keep looking in - // this node until we find it (or we realize it's not there either, in which - // case it's actually not in the dictionary). Pass the end of this group, ready - // to start the next one. - pos = skipChildrenPosAndAttributes(root, flags, pos); - } - } else { - // If we did not find it, we should record the last children address for the next - // iteration. - if (hasChildren) lastCandidateGroupPos = startPos; - // Now skip the end of this group (children pos and the attributes if any) so that - // our pos is after the end of this char group, at the start of the next one. - pos = skipChildrenPosAndAttributes(root, flags, pos); - } - - } - } - // If we have looked through all the chargroups and found no match, the address is - // not the address of a terminal in this dictionary. - return 0; -} - -} // namespace latinime -#endif // LATINIME_BINARY_FORMAT_H diff --git a/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.cpp index 3e664a29b..15eb0674d 100644 --- a/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.cpp +++ b/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.cpp @@ -20,7 +20,6 @@ #include "defines.h" #include "suggest/core/dicnode/dic_node.h" #include "suggest/core/dicnode/dic_node_vector.h" -#include "suggest/policyimpl/dictionary/binary_format.h" #include "suggest/policyimpl/dictionary/patricia_trie_reading_utils.h" namespace latinime { @@ -38,17 +37,273 @@ void PatriciaTriePolicy::createAndGetAllChildNodes(const DicNode *const dicNode, } } +// This retrieves code points and the probability of the word by its terminal position. +// Due to the fact that words are ordered in the dictionary in a strict breadth-first order, +// it is possible to check for this with advantageous complexity. For each node, we search +// for groups with children and compare the children position with the position we look for. +// When we shoot the position we look for, it means the word we look for is in the children +// of the previous group. The only tricky part is the fact that if we arrive at the end of a +// node with the last group's children position still less than what we are searching for, we +// must descend the last group's children (for example, if the word we are searching for starts +// with a z, it's the last group of the root node, so all children addresses will be smaller +// than the position we look for, and we have to descend the z node). +/* Parameters : + * nodePos: the byte position of the terminal chargroup of the word we are searching for (this is + * what is stored as the "bigram position" in each bigram) + * outCodePoints: an array to write the found word, with MAX_WORD_LENGTH size. + * outUnigramProbability: a pointer to an int to write the probability into. + * Return value : the code point count, of 0 if the word was not found. + */ +// TODO: Split this function to be more readable int PatriciaTriePolicy::getCodePointsAndProbabilityAndReturnCodePointCount( const int nodePos, const int maxCodePointCount, int *const outCodePoints, int *const outUnigramProbability) const { - return BinaryFormat::getCodePointsAndProbabilityAndReturnCodePointCount(mDictRoot, nodePos, - maxCodePointCount, outCodePoints, outUnigramProbability); + int pos = getRootPosition(); + int wordPos = 0; + // One iteration of the outer loop iterates through nodes. As stated above, we will only + // traverse nodes that are actually a part of the terminal we are searching, so each time + // we enter this loop we are one depth level further than last time. + // The only reason we count nodes is because we want to reduce the probability of infinite + // looping in case there is a bug. Since we know there is an upper bound to the depth we are + // supposed to traverse, it does not hurt to count iterations. + for (int loopCount = maxCodePointCount; loopCount > 0; --loopCount) { + int lastCandidateGroupPos = 0; + // Let's loop through char groups in this node searching for either the terminal + // or one of its ascendants. + for (int charGroupCount = PatriciaTrieReadingUtils::getGroupCountAndAdvancePosition( + mDictRoot, &pos); charGroupCount > 0; --charGroupCount) { + const int startPos = pos; + const PatriciaTrieReadingUtils::NodeFlags flags = + PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(mDictRoot, &pos); + const int character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &pos); + if (nodePos == startPos) { + // We found the position. Copy the rest of the code points in the buffer and return + // the length. + outCodePoints[wordPos] = character; + if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) { + int nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &pos); + // We count code points in order to avoid infinite loops if the file is broken + // or if there is some other bug + int charCount = maxCodePointCount; + while (NOT_A_CODE_POINT != nextChar && --charCount > 0) { + outCodePoints[++wordPos] = nextChar; + nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &pos); + } + } + *outUnigramProbability = + PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, + &pos); + return ++wordPos; + } + // We need to skip past this char group, so skip any remaining code points after the + // first and possibly the probability. + if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) { + PatriciaTrieReadingUtils::skipCharacters(mDictRoot, flags, MAX_WORD_LENGTH, &pos); + } + if (PatriciaTrieReadingUtils::isTerminal(flags)) { + PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, &pos); + } + // The fact that this group has children is very important. Since we already know + // that this group does not match, if it has no children we know it is irrelevant + // to what we are searching for. + const bool hasChildren = PatriciaTrieReadingUtils::hasChildrenInFlags(flags); + // We will write in `found' whether we have passed the children position we are + // searching for. For example if we search for "beer", the children of b are less + // than the address we are searching for and the children of c are greater. When we + // come here for c, we realize this is too big, and that we should descend b. + bool found; + if (hasChildren) { + int currentPos = pos; + // Here comes the tricky part. First, read the children position. + const int childrenPos = PatriciaTrieReadingUtils + ::readChildrenPositionAndAdvancePosition(mDictRoot, flags, ¤tPos); + if (childrenPos > nodePos) { + // If the children pos is greater than the position, it means the previous + // chargroup, which position is stored in lastCandidateGroupPos, was the right + // one. + found = true; + } else if (1 >= charGroupCount) { + // However if we are on the LAST group of this node, and we have NOT shot the + // position we should descend THIS node. So we trick the lastCandidateGroupPos + // so that we will descend this node, not the previous one. + lastCandidateGroupPos = startPos; + found = true; + } else { + // Else, we should continue looking. + found = false; + } + } else { + // Even if we don't have children here, we could still be on the last group of this + // node. If this is the case, we should descend the last group that had children, + // and their position is already in lastCandidateGroup. + found = (1 >= charGroupCount); + } + + if (found) { + // Okay, we found the group we should descend. Its position is in + // the lastCandidateGroupPos variable, so we just re-read it. + if (0 != lastCandidateGroupPos) { + const PatriciaTrieReadingUtils::NodeFlags lastFlags = + PatriciaTrieReadingUtils::getFlagsAndAdvancePosition( + mDictRoot, &lastCandidateGroupPos); + const int lastChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &lastCandidateGroupPos); + // We copy all the characters in this group to the buffer + outCodePoints[wordPos] = lastChar; + if (PatriciaTrieReadingUtils::hasMultipleChars(lastFlags)) { + int nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &lastCandidateGroupPos); + int charCount = maxCodePointCount; + while (-1 != nextChar && --charCount > 0) { + outCodePoints[++wordPos] = nextChar; + nextChar = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &lastCandidateGroupPos); + } + } + ++wordPos; + // Now we only need to branch to the children address. Skip the probability if + // it's there, read pos, and break to resume the search at pos. + if (PatriciaTrieReadingUtils::isTerminal(lastFlags)) { + PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, + &lastCandidateGroupPos); + } + pos = PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition( + mDictRoot, lastFlags, &lastCandidateGroupPos); + break; + } else { + // Here is a little tricky part: we come here if we found out that all children + // addresses in this group are bigger than the address we are searching for. + // Should we conclude the word is not in the dictionary? No! It could still be + // one of the remaining chargroups in this node, so we have to keep looking in + // this node until we find it (or we realize it's not there either, in which + // case it's actually not in the dictionary). Pass the end of this group, ready + // to start the next one. + if (PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) { + PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition( + mDictRoot, flags, &pos); + } + if (PatriciaTrieReadingUtils::hasShortcutTargets(flags)) { + mShortcutListPolicy.skipAllShortcuts(&pos); + } + if (PatriciaTrieReadingUtils::hasBigrams(flags)) { + mBigramListPolicy.skipAllBigrams(&pos); + } + } + } else { + // If we did not find it, we should record the last children address for the next + // iteration. + if (hasChildren) lastCandidateGroupPos = startPos; + // Now skip the end of this group (children pos and the attributes if any) so that + // our pos is after the end of this char group, at the start of the next one. + if (PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) { + PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition( + mDictRoot, flags, &pos); + } + if (PatriciaTrieReadingUtils::hasShortcutTargets(flags)) { + mShortcutListPolicy.skipAllShortcuts(&pos); + } + if (PatriciaTrieReadingUtils::hasBigrams(flags)) { + mBigramListPolicy.skipAllBigrams(&pos); + } + } + + } + } + // If we have looked through all the chargroups and found no match, the nodePos is + // not the position of a terminal in this dictionary. + return 0; } +// This function gets the position of the terminal node of the exact matching word in the +// dictionary. If no match is found, it returns NOT_A_VALID_WORD_POS. int PatriciaTriePolicy::getTerminalNodePositionOfWord(const int *const inWord, const int length, const bool forceLowerCaseSearch) const { - return BinaryFormat::getTerminalPosition(mDictRoot, inWord, - length, forceLowerCaseSearch); + int pos = getRootPosition(); + int wordPos = 0; + + while (true) { + // If we already traversed the tree further than the word is long, there means + // there was no match (or we would have found it). + if (wordPos >= length) return NOT_A_VALID_WORD_POS; + int charGroupCount = PatriciaTrieReadingUtils::getGroupCountAndAdvancePosition(mDictRoot, + &pos); + const int wChar = forceLowerCaseSearch + ? CharUtils::toLowerCase(inWord[wordPos]) : inWord[wordPos]; + while (true) { + // If there are no more character groups in this node, it means we could not + // find a matching character for this depth, therefore there is no match. + if (0 >= charGroupCount) return NOT_A_VALID_WORD_POS; + const int charGroupPos = pos; + const PatriciaTrieReadingUtils::NodeFlags flags = + PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(mDictRoot, &pos); + int character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(mDictRoot, + &pos); + if (character == wChar) { + // This is the correct node. Only one character group may start with the same + // char within a node, so either we found our match in this node, or there is + // no match and we can return NOT_A_VALID_WORD_POS. So we will check all the + // characters in this character group indeed does match. + if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) { + character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition(mDictRoot, + &pos); + while (NOT_A_CODE_POINT != character) { + ++wordPos; + // If we shoot the length of the word we search for, or if we find a single + // character that does not match, as explained above, it means the word is + // not in the dictionary (by virtue of this chargroup being the only one to + // match the word on the first character, but not matching the whole word). + if (wordPos >= length) return NOT_A_VALID_WORD_POS; + if (inWord[wordPos] != character) return NOT_A_VALID_WORD_POS; + character = PatriciaTrieReadingUtils::getCodePointAndAdvancePosition( + mDictRoot, &pos); + } + } + // If we come here we know that so far, we do match. Either we are on a terminal + // and we match the length, in which case we found it, or we traverse children. + // If we don't match the length AND don't have children, then a word in the + // dictionary fully matches a prefix of the searched word but not the full word. + ++wordPos; + if (PatriciaTrieReadingUtils::isTerminal(flags)) { + if (wordPos == length) { + return charGroupPos; + } + PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, &pos); + } + if (!PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) { + return NOT_A_VALID_WORD_POS; + } + // We have children and we are still shorter than the word we are searching for, so + // we need to traverse children. Put the pointer on the children position, and + // break + pos = PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(mDictRoot, + flags, &pos); + break; + } else { + // This chargroup does not match, so skip the remaining part and go to the next. + if (PatriciaTrieReadingUtils::hasMultipleChars(flags)) { + PatriciaTrieReadingUtils::skipCharacters(mDictRoot, flags, MAX_WORD_LENGTH, + &pos); + } + if (PatriciaTrieReadingUtils::isTerminal(flags)) { + PatriciaTrieReadingUtils::readProbabilityAndAdvancePosition(mDictRoot, &pos); + } + if (PatriciaTrieReadingUtils::hasChildrenInFlags(flags)) { + PatriciaTrieReadingUtils::readChildrenPositionAndAdvancePosition(mDictRoot, + flags, &pos); + } + if (PatriciaTrieReadingUtils::hasShortcutTargets(flags)) { + mShortcutListPolicy.skipAllShortcuts(&pos); + } + if (PatriciaTrieReadingUtils::hasBigrams(flags)) { + mBigramListPolicy.skipAllBigrams(&pos); + } + } + --charGroupCount; + } + } } int PatriciaTriePolicy::getUnigramProbability(const int nodePos) const {