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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 1996-2012, International Business Machines Corporation and
* others. All Rights Reserved.
*******************************************************************************
*/
//===============================================================================
//
// File sortkey.cpp
//
//
//
// Created by: Helena Shih
//
// Modification History:
//
// Date Name Description
//
// 6/20/97 helena Java class name change.
// 6/23/97 helena Added comments to make code more readable.
// 6/26/98 erm Canged to use byte arrays instead of UnicodeString
// 7/31/98 erm hashCode: minimum inc should be 2 not 1,
// Cleaned up operator=
// 07/12/99 helena HPUX 11 CC port.
// 03/06/01 synwee Modified compareTo, to handle the result of
// 2 string similar in contents, but one is longer
// than the other
//===============================================================================
#include "unicode/utypes.h"
#if !UCONFIG_NO_COLLATION
#include "unicode/sortkey.h"
#include "cmemory.h"
#include "uelement.h"
#include "ustr_imp.h"
U_NAMESPACE_BEGIN
// A hash code of kInvalidHashCode indicates that the hash code needs
// to be computed. A hash code of kEmptyHashCode is used for empty keys
// and for any key whose computed hash code is kInvalidHashCode.
static const int32_t kInvalidHashCode = 0;
static const int32_t kEmptyHashCode = 1;
// The "bogus hash code" replaces a separate fBogus flag.
static const int32_t kBogusHashCode = 2;
UOBJECT_DEFINE_RTTI_IMPLEMENTATION(CollationKey)
CollationKey::CollationKey()
: UObject(), fFlagAndLength(0),
fHashCode(kEmptyHashCode)
{
}
// Create a collation key from a bit array.
CollationKey::CollationKey(const uint8_t* newValues, int32_t count)
: UObject(), fFlagAndLength(count),
fHashCode(kInvalidHashCode)
{
if (count < 0 || (newValues == NULL && count != 0) ||
(count > getCapacity() && reallocate(count, 0) == NULL)) {
setToBogus();
return;
}
if (count > 0) {
uprv_memcpy(getBytes(), newValues, count);
}
}
CollationKey::CollationKey(const CollationKey& other)
: UObject(other), fFlagAndLength(other.getLength()),
fHashCode(other.fHashCode)
{
if (other.isBogus())
{
setToBogus();
return;
}
int32_t length = fFlagAndLength;
if (length > getCapacity() && reallocate(length, 0) == NULL) {
setToBogus();
return;
}
if (length > 0) {
uprv_memcpy(getBytes(), other.getBytes(), length);
}
}
CollationKey::~CollationKey()
{
if(fFlagAndLength < 0) { uprv_free(fUnion.fFields.fBytes); }
}
uint8_t *CollationKey::reallocate(int32_t newCapacity, int32_t length) {
uint8_t *newBytes = static_cast<uint8_t *>(uprv_malloc(newCapacity));
if(newBytes == NULL) { return NULL; }
if(length > 0) {
uprv_memcpy(newBytes, getBytes(), length);
}
if(fFlagAndLength < 0) { uprv_free(fUnion.fFields.fBytes); }
fUnion.fFields.fBytes = newBytes;
fUnion.fFields.fCapacity = newCapacity;
fFlagAndLength |= 0x80000000;
return newBytes;
}
void CollationKey::setLength(int32_t newLength) {
// U_ASSERT(newLength >= 0 && newLength <= getCapacity());
fFlagAndLength = (fFlagAndLength & 0x80000000) | newLength;
fHashCode = kInvalidHashCode;
}
// set the key to an empty state
CollationKey&
CollationKey::reset()
{
fFlagAndLength &= 0x80000000;
fHashCode = kEmptyHashCode;
return *this;
}
// set the key to a "bogus" or invalid state
CollationKey&
CollationKey::setToBogus()
{
fFlagAndLength &= 0x80000000;
fHashCode = kBogusHashCode;
return *this;
}
UBool
CollationKey::operator==(const CollationKey& source) const
{
return getLength() == source.getLength() &&
(this == &source ||
uprv_memcmp(getBytes(), source.getBytes(), getLength()) == 0);
}
const CollationKey&
CollationKey::operator=(const CollationKey& other)
{
if (this != &other)
{
if (other.isBogus())
{
return setToBogus();
}
int32_t length = other.getLength();
if (length > getCapacity() && reallocate(length, 0) == NULL) {
return setToBogus();
}
if (length > 0) {
uprv_memcpy(getBytes(), other.getBytes(), length);
}
fFlagAndLength = (fFlagAndLength & 0x80000000) | length;
fHashCode = other.fHashCode;
}
return *this;
}
// Bitwise comparison for the collation keys.
Collator::EComparisonResult
CollationKey::compareTo(const CollationKey& target) const
{
UErrorCode errorCode = U_ZERO_ERROR;
return static_cast<Collator::EComparisonResult>(compareTo(target, errorCode));
}
// Bitwise comparison for the collation keys.
UCollationResult
CollationKey::compareTo(const CollationKey& target, UErrorCode &status) const
{
if(U_SUCCESS(status)) {
const uint8_t *src = getBytes();
const uint8_t *tgt = target.getBytes();
// are we comparing the same string
if (src == tgt)
return UCOL_EQUAL;
UCollationResult result;
// are we comparing different lengths?
int32_t minLength = getLength();
int32_t targetLength = target.getLength();
if (minLength < targetLength) {
result = UCOL_LESS;
} else if (minLength == targetLength) {
result = UCOL_EQUAL;
} else {
minLength = targetLength;
result = UCOL_GREATER;
}
if (minLength > 0) {
int diff = uprv_memcmp(src, tgt, minLength);
if (diff > 0) {
return UCOL_GREATER;
}
else
if (diff < 0) {
return UCOL_LESS;
}
}
return result;
} else {
return UCOL_EQUAL;
}
}
#ifdef U_USE_COLLATION_KEY_DEPRECATES
// Create a copy of the byte array.
uint8_t*
CollationKey::toByteArray(int32_t& count) const
{
uint8_t *result = (uint8_t*) uprv_malloc( sizeof(uint8_t) * fCount );
if (result == NULL)
{
count = 0;
}
else
{
count = fCount;
if (count > 0) {
uprv_memcpy(result, fBytes, fCount);
}
}
return result;
}
#endif
static int32_t
computeHashCode(const uint8_t *key, int32_t length) {
const char *s = reinterpret_cast<const char *>(key);
int32_t hash;
if (s == NULL || length == 0) {
hash = kEmptyHashCode;
} else {
hash = ustr_hashCharsN(s, length);
if (hash == kInvalidHashCode || hash == kBogusHashCode) {
hash = kEmptyHashCode;
}
}
return hash;
}
int32_t
CollationKey::hashCode() const
{
// (Cribbed from UnicodeString)
// We cache the hashCode; when it becomes invalid, due to any change to the
// string, we note this by setting it to kInvalidHashCode. [LIU]
// Note: This method is semantically const, but physically non-const.
if (fHashCode == kInvalidHashCode)
{
fHashCode = computeHashCode(getBytes(), getLength());
}
return fHashCode;
}
U_NAMESPACE_END
U_CAPI int32_t U_EXPORT2
ucol_keyHashCode(const uint8_t *key,
int32_t length)
{
return icu::computeHashCode(key, length);
}
#endif /* #if !UCONFIG_NO_COLLATION */