scuffed-code/icu4c/source/i18n/cpdtrans.cpp

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/*
**********************************************************************
* Copyright (C) 1999, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
* Date Name Description
* 11/17/99 aliu Creation.
**********************************************************************
*/
/* These APIs are becoming private */
#define ICU_COMPOUNDTRANSLITERATOR_USE_DEPRECATES 1
#include "unicode/cpdtrans.h"
#include "unicode/unifilt.h"
#include "unicode/unifltlg.h"
#include "unicode/uniset.h"
#include "uvector.h"
#include "tridpars.h"
#include "cmemory.h"
// keep in sync with Transliterator
static const UChar ID_SEP = 0x002D; /*-*/
static const UChar ID_DELIM = 0x003B; /*;*/
static const UChar NEWLINE = 10;
// Empty string
static const UChar EMPTY[] = {0}; //""
U_NAMESPACE_BEGIN
const char CompoundTransliterator::fgClassID=0;
/**
* Constructs a new compound transliterator given an array of
* transliterators. The array of transliterators may be of any
* length, including zero or one, however, useful compound
* transliterators have at least two components.
* @param transliterators array of <code>Transliterator</code>
* objects
* @param transliteratorCount The number of
* <code>Transliterator</code> objects in transliterators.
* @param filter the filter. Any character for which
* <tt>filter.contains()</tt> returns <tt>false</tt> will not be
* altered by this transliterator. If <tt>filter</tt> is
* <tt>null</tt> then no filtering is applied.
*/
CompoundTransliterator::CompoundTransliterator(
Transliterator* const transliterators[],
int32_t transliteratorCount,
UnicodeFilter* adoptedFilter) :
Transliterator(joinIDs(transliterators, transliteratorCount), adoptedFilter),
trans(0), count(0), compoundRBTIndex(-1) {
setTransliterators(transliterators, transliteratorCount);
}
/**
* Splits an ID of the form "ID;ID;..." into a compound using each
* of the IDs.
* @param id of above form
* @param forward if false, does the list in reverse order, and
* takes the inverse of each ID.
*/
CompoundTransliterator::CompoundTransliterator(const UnicodeString& id,
UTransDirection direction,
UnicodeFilter* adoptedFilter,
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UParseError& /*parseError*/,
UErrorCode& status) :
Transliterator(id, adoptedFilter),
trans(0), compoundRBTIndex(-1) {
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// TODO add code for parseError...currently unused, but
// later may be used by parsing code...
init(id, direction, -1, 0, TRUE, status);
}
CompoundTransliterator::CompoundTransliterator(const UnicodeString& id,
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UParseError& /*parseError*/,
UErrorCode& status) :
Transliterator(id, 0), // set filter to 0 here!
trans(0), compoundRBTIndex(-1) {
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// TODO add code for parseError...currently unused, but
// later may be used by parsing code...
init(id, UTRANS_FORWARD, -1, 0, TRUE, status);
}
/**
* Private constructor for Transliterator from a vector of
* transliterators. The caller is responsible for fixing up the
* ID.
*/
CompoundTransliterator::CompoundTransliterator(UVector& list,
UParseError& /*parseError*/,
UErrorCode& status) :
Transliterator(EMPTY, NULL),
trans(0), compoundRBTIndex(-1)
{
// TODO add code for parseError...currently unused, but
// later may be used by parsing code...
init(list, UTRANS_FORWARD, FALSE, status);
// assume caller will fixup ID
}
/**
* Private constructor for compound RBTs. Construct a compound
* transliterator using the given idBlock, with the adoptedTrans
* inserted at the idSplitPoint.
*/
CompoundTransliterator::CompoundTransliterator(const UnicodeString& newID,
const UnicodeString& idBlock,
int32_t idSplitPoint,
Transliterator *adoptedTrans,
UErrorCode& status) :
Transliterator(newID, 0),
trans(0), compoundRBTIndex(-1)
{
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init(idBlock, UTRANS_FORWARD, idSplitPoint, adoptedTrans, FALSE, status);
}
/**
* Finish constructing a transliterator: only to be called by
* constructors. Before calling init(), set trans and filter to NULL.
* @param id the id containing ';'-separated entries
* @param direction either FORWARD or REVERSE
* @param idSplitPoint the index into id at which the
* adoptedSplitTransliterator should be inserted, if there is one, or
* -1 if there is none.
* @param adoptedSplitTransliterator a transliterator to be inserted
* before the entry at offset idSplitPoint in the id string. May be
* NULL to insert no entry.
* @param fixReverseID if TRUE, then reconstruct the ID of reverse
* entries by calling getID() of component entries. Some constructors
* do not require this because they apply a facade ID anyway.
* @param status the error code indicating success or failure
*/
void CompoundTransliterator::init(const UnicodeString& id,
UTransDirection direction,
int32_t idSplitPoint,
Transliterator *adoptedSplitTrans,
UBool fixReverseID,
UErrorCode& status) {
// assert(trans == 0);
if (U_FAILURE(status)) {
delete adoptedSplitTrans;
return;
}
UVector list(status);
UnicodeSet* compoundFilter = NULL;
UnicodeString regenID;
if (!TransliteratorIDParser::parseCompoundID(id, direction,
regenID, list, compoundFilter)) {
status = U_INVALID_ID;
delete adoptedSplitTrans;
delete compoundFilter;
return;
}
compoundRBTIndex = TransliteratorIDParser::instantiateList(list, adoptedSplitTrans, idSplitPoint, status);
init(list, direction, fixReverseID, status);
if (compoundFilter != NULL) {
adoptFilter(compoundFilter);
}
}
/**
* Finish constructing a transliterator: only to be called by
* constructors. Before calling init(), set trans and filter to NULL.
* @param list a vector of transliterator objects to be adopted. It
* should NOT be empty. The list should be in declared order. That
* is, it should be in the FORWARD order; if direction is REVERSE then
* the list order will be reversed.
* @param direction either FORWARD or REVERSE
* @param fixReverseID if TRUE, then reconstruct the ID of reverse
* entries by calling getID() of component entries. Some constructors
* do not require this because they apply a facade ID anyway.
* @param status the error code indicating success or failure
*/
void CompoundTransliterator::init(UVector& list,
UTransDirection direction,
UBool fixReverseID,
UErrorCode& status) {
// assert(trans == 0);
// Allocate array
if (U_SUCCESS(status)) {
count = list.size();
trans = (Transliterator **)uprv_malloc(count * sizeof(Transliterator *));
/* test for NULL */
if (trans == 0) {
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
}
if (U_FAILURE(status) || trans == 0) {
// assert(trans == 0);
return;
}
// Move the transliterators from the vector into an array.
// Reverse the order if necessary.
int32_t i;
for (i=0; i<count; ++i) {
int32_t j = (direction == UTRANS_FORWARD) ? i : count - 1 - i;
trans[i] = (Transliterator*) list.elementAt(j);
}
// Fix compoundRBTIndex for REVERSE transliterators
if (compoundRBTIndex >= 0 && direction == UTRANS_REVERSE) {
compoundRBTIndex = count - 1 - compoundRBTIndex;
}
// If the direction is UTRANS_REVERSE then we may need to fix the
// ID.
if (direction == UTRANS_REVERSE && fixReverseID) {
UnicodeString newID;
for (i=0; i<count; ++i) {
if (i > 0) {
newID.append(ID_DELIM);
}
newID.append(trans[i]->getID());
}
setID(newID);
}
computeMaximumContextLength();
}
/**
* Return the IDs of the given list of transliterators, concatenated
* with ID_DELIM delimiting them. Equivalent to the perlish expression
* join(ID_DELIM, map($_.getID(), transliterators).
*/
UnicodeString CompoundTransliterator::joinIDs(Transliterator* const transliterators[],
int32_t transCount) {
UnicodeString id;
for (int32_t i=0; i<transCount; ++i) {
if (i > 0) {
id.append(ID_DELIM);
}
id.append(transliterators[i]->getID());
}
return id; // Return temporary
}
/**
* Copy constructor.
*/
CompoundTransliterator::CompoundTransliterator(const CompoundTransliterator& t) :
Transliterator(t), trans(0), count(0), compoundRBTIndex(-1) {
*this = t;
}
/**
* Destructor
*/
CompoundTransliterator::~CompoundTransliterator() {
freeTransliterators();
}
void CompoundTransliterator::freeTransliterators(void) {
if (trans != 0) {
for (int32_t i=0; i<count; ++i) {
delete trans[i];
}
uprv_free(trans);
}
trans = 0;
count = 0;
}
/**
* Assignment operator.
*/
CompoundTransliterator& CompoundTransliterator::operator=(
const CompoundTransliterator& t) {
Transliterator::operator=(t);
int32_t i;
for (i=0; i<count; ++i) {
delete trans[i];
trans[i] = 0;
}
if (t.count > count) {
uprv_free(trans);
trans = (Transliterator **)uprv_malloc(t.count * sizeof(Transliterator *));
}
count = t.count;
for (i=0; i<count; ++i) {
trans[i] = t.trans[i]->clone();
}
compoundRBTIndex = t.compoundRBTIndex;
return *this;
}
/**
* Transliterator API.
*/
Transliterator* CompoundTransliterator::clone(void) const {
return new CompoundTransliterator(*this);
}
/**
* Returns the number of transliterators in this chain.
* @return number of transliterators in this chain.
*/
int32_t CompoundTransliterator::getCount(void) const {
return count;
}
/**
* Returns the transliterator at the given index in this chain.
* @param index index into chain, from 0 to <code>getCount() - 1</code>
* @return transliterator at the given index
*/
const Transliterator& CompoundTransliterator::getTransliterator(int32_t index) const {
return *trans[index];
}
void CompoundTransliterator::setTransliterators(Transliterator* const transliterators[],
int32_t transCount) {
Transliterator** a = (Transliterator **)uprv_malloc(transCount * sizeof(Transliterator *));
for (int32_t i=0; i<transCount; ++i) {
a[i] = transliterators[i]->clone();
}
adoptTransliterators(a, transCount);
}
void CompoundTransliterator::adoptTransliterators(Transliterator* adoptedTransliterators[],
int32_t transCount) {
// First free trans[] and set count to zero. Once this is done,
// orphan the filter. Set up the new trans[].
freeTransliterators();
trans = adoptedTransliterators;
count = transCount;
computeMaximumContextLength();
setID(joinIDs(trans, count));
}
/**
* Append c to buf, unless buf is empty or buf already ends in c.
*/
static void _smartAppend(UnicodeString& buf, UChar c) {
if (buf.length() != 0 &&
buf.charAt(buf.length() - 1) != c) {
buf.append(c);
}
}
UnicodeString& CompoundTransliterator::toRules(UnicodeString& rulesSource,
UBool escapeUnprintable) const {
// We do NOT call toRules() on our component transliterators, in
// general. If we have several rule-based transliterators, this
// yields a concatenation of the rules -- not what we want. We do
// handle compound RBT transliterators specially -- those for which
// compoundRBTIndex >= 0. For the transliterator at compoundRBTIndex,
// we do call toRules() recursively.
rulesSource.truncate(0);
if (compoundRBTIndex >= 0 && getFilter() != NULL) {
// If we are a compound RBT and if we have a global
// filter, then emit it at the top.
UnicodeString pat;
rulesSource.append("::").append(getFilter()->toPattern(pat, escapeUnprintable)).append(ID_DELIM);
}
for (int32_t i=0; i<count; ++i) {
UnicodeString rule;
if (i == compoundRBTIndex) {
trans[i]->toRules(rule, escapeUnprintable);
} else {
trans[i]->Transliterator::toRules(rule, escapeUnprintable);
}
_smartAppend(rulesSource, NEWLINE);
rulesSource.append(rule);
_smartAppend(rulesSource, ID_DELIM);
}
return rulesSource;
}
/**
* Implement Transliterator framework
*/
void CompoundTransliterator::handleGetSourceSet(UnicodeSet& result) const {
UnicodeSet set;
result.clear();
for (int32_t i=0; i<count; ++i) {
result.addAll(trans[i]->getSourceSet(set));
// Take the example of Hiragana-Latin. This is really
// Hiragana-Katakana; Katakana-Latin. The source set of
// these two is roughly [:Hiragana:] and [:Katakana:].
// But the source set for the entire transliterator is
// actually [:Hiragana:] ONLY -- that is, the first
// non-empty source set.
// This is a heuristic, and not 100% reliable.
if (!result.isEmpty()) {
break;
}
}
}
/**
* Override Transliterator framework
*/
UnicodeSet& CompoundTransliterator::getTargetSet(UnicodeSet& result) const {
UnicodeSet set;
result.clear();
for (int32_t i=0; i<count; ++i) {
// This is a heuristic, and not 100% reliable.
result.addAll(trans[i]->getTargetSet(set));
}
return result;
}
/**
* Implements {@link Transliterator#handleTransliterate}.
*/
void CompoundTransliterator::handleTransliterate(Replaceable& text, UTransPosition& index,
UBool incremental) const {
/* Call each transliterator with the same contextStart and
* start, but with the limit as modified
* by preceding transliterators. The start index must be
* reset for each transliterator to give each a chance to
* transliterate the text. The initial contextStart index is known
* to still point to the same place after each transliterator
* is called because each transliterator will not change the
* text between contextStart and the initial start index.
*
* IMPORTANT: After the first transliterator, each subsequent
* transliterator only gets to transliterate text committed by
* preceding transliterators; that is, the start (output
* value) of transliterator i becomes the limit (input value)
* of transliterator i+1. Finally, the overall limit is fixed
* up before we return.
*
* Assumptions we make here:
* (1) contextStart <= start <= limit <= contextLimit <= text.length()
* (2) start <= start' <= limit' ;cursor doesn't move back
* (3) start <= limit' ;text before cursor unchanged
* - start' is the value of start after calling handleKT
* - limit' is the value of limit after calling handleKT
*/
/**
* Example: 3 transliterators. This example illustrates the
* mechanics we need to implement. C, S, and L are the contextStart,
* start, and limit. gl is the globalLimit. contextLimit is
* equal to limit throughout.
*
* 1. h-u, changes hex to Unicode
*
* 4 7 a d 0 4 7 a
* abc/u0061/u => abca/u
* C S L C S L gl=f->a
*
* 2. upup, changes "x" to "XX"
*
* 4 7 a 4 7 a
* abca/u => abcAA/u
* C SL C S
* L gl=a->b
* 3. u-h, changes Unicode to hex
*
* 4 7 a 4 7 a d 0 3
* abcAA/u => abc/u0041/u0041/u
* C S L C S
* L gl=b->15
* 4. return
*
* 4 7 a d 0 3
* abc/u0041/u0041/u
* C S L
*/
if (count < 1) {
index.start = index.limit;
return; // Short circuit for empty compound transliterators
}
// compoundLimit is the limit value for the entire compound
// operation. We overwrite index.limit with the previous
// index.start. After each transliteration, we update
// compoundLimit for insertions or deletions that have happened.
int32_t compoundLimit = index.limit;
// compoundStart is the start for the entire compound
// operation.
int32_t compoundStart = index.start;
int32_t delta = 0; // delta in length
// Give each transliterator a crack at the run of characters.
// See comments at the top of the method for more detail.
for (int32_t i=0; i<count; ++i) {
index.start = compoundStart; // Reset start
int32_t limit = index.limit;
if (index.start == index.limit) {
// Short circuit for empty range
break;
}
trans[i]->filteredTransliterate(text, index, incremental);
// In a properly written transliterator, start == limit after
// handleTransliterate() returns when incremental is false.
// Catch cases where the subclass doesn't do this, and throw
// an exception. (Just pinning start to limit is a bad idea,
// because what's probably happening is that the subclass
// isn't transliterating all the way to the end, and it should
// in non-incremental mode.)
if (!incremental && index.start != index.limit) {
// We can't throw an exception, so just fudge things
index.start = index.limit;
}
// Cumulative delta for insertions/deletions
delta += index.limit - limit;
if (incremental) {
// In the incremental case, only allow subsequent
// transliterators to modify what has already been
// completely processed by prior transliterators. In the
// non-incrmental case, allow each transliterator to
// process the entire text.
index.limit = index.start;
}
}
compoundLimit += delta;
// Start is good where it is -- where the last transliterator left
// it. Limit needs to be put back where it was, modulo
// adjustments for deletions/insertions.
index.limit = compoundLimit;
}
/**
* Sets the length of the longest context required by this transliterator.
* This is <em>preceding</em> context.
*/
void CompoundTransliterator::computeMaximumContextLength(void) {
int32_t max = 0;
for (int32_t i=0; i<count; ++i) {
int32_t len = trans[i]->getMaximumContextLength();
if (len > max) {
max = len;
}
}
setMaximumContextLength(max);
}
U_NAMESPACE_END
/* eof */