scuffed-code/icu4c/source/common/uiter.cpp
Steven R. Loomis 8185a8ce05 ICU-1686 UCharIterator: use -1 for error code
X-SVN-Rev: 8346
2002-04-02 23:35:24 +00:00

430 lines
11 KiB
C++

/*
*******************************************************************************
*
* Copyright (C) 2002, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: uiter.cpp
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2002jan18
* created by: Markus W. Scherer
*/
#include "unicode/utypes.h"
#include "unicode/ustring.h"
#include "unicode/chariter.h"
#include "unicode/rep.h"
#include "unicode/uiter.h"
U_CDECL_BEGIN
/* No-Op UCharIterator implementation for illegal input --------------------- */
static int32_t U_CALLCONV
noopGetIndex(UCharIterator * /*iter*/, UCharIteratorOrigin /*origin*/) {
return 0;
}
static int32_t U_CALLCONV
noopMove(UCharIterator * /*iter*/, int32_t /*delta*/, UCharIteratorOrigin /*origin*/) {
return 0;
}
static UBool U_CALLCONV
noopHasNext(UCharIterator * /*iter*/) {
return FALSE;
}
static int32_t U_CALLCONV
noopCurrent(UCharIterator * /*iter*/) {
return -1;
}
static const UCharIterator noopIterator={
0, 0, 0, 0, 0, 0,
noopGetIndex,
noopMove,
noopHasNext,
noopHasNext,
noopCurrent,
noopCurrent,
noopCurrent,
0
};
/* UCharIterator implementation for simple strings -------------------------- */
/*
* This is an implementation of a code unit (UChar) iterator
* for UChar * strings.
*
* The UCharIterator.context field holds a pointer to the string.
*/
static int32_t U_CALLCONV
stringIteratorGetIndex(UCharIterator *iter, UCharIteratorOrigin origin) {
switch(origin) {
case UITER_ZERO:
return 0;
case UITER_START:
return iter->start;
case UITER_CURRENT:
return iter->index;
case UITER_LIMIT:
return iter->limit;
case UITER_LENGTH:
return iter->length;
default:
/* not a valid origin */
/* Should never get here! */
return -1;
}
}
static int32_t U_CALLCONV
stringIteratorMove(UCharIterator *iter, int32_t delta, UCharIteratorOrigin origin) {
int32_t pos;
switch(origin) {
case UITER_ZERO:
pos=delta;
break;
case UITER_START:
pos=iter->start+delta;
break;
case UITER_CURRENT:
pos=iter->index+delta;
break;
case UITER_LIMIT:
pos=iter->limit+delta;
break;
case UITER_LENGTH:
pos=iter->length+delta;
break;
default:
return -1; /* Error */
}
if(pos<iter->start) {
pos=iter->start;
} else if(pos>iter->limit) {
pos=iter->limit;
}
return iter->index=pos;
}
static UBool U_CALLCONV
stringIteratorHasNext(UCharIterator *iter) {
return iter->index<iter->limit;
}
static UBool U_CALLCONV
stringIteratorHasPrevious(UCharIterator *iter) {
return iter->index>iter->start;
}
static int32_t U_CALLCONV
stringIteratorCurrent(UCharIterator *iter) {
if(iter->index<iter->limit) {
return ((const UChar *)(iter->context))[iter->index];
} else {
return -1;
}
}
static int32_t U_CALLCONV
stringIteratorNext(UCharIterator *iter) {
if(iter->index<iter->limit) {
return ((const UChar *)(iter->context))[iter->index++];
} else {
return -1;
}
}
static int32_t U_CALLCONV
stringIteratorPrevious(UCharIterator *iter) {
if(iter->index>iter->start) {
return ((const UChar *)(iter->context))[--iter->index];
} else {
return -1;
}
}
static const UCharIterator stringIterator={
0, 0, 0, 0, 0, 0,
stringIteratorGetIndex,
stringIteratorMove,
stringIteratorHasNext,
stringIteratorHasPrevious,
stringIteratorCurrent,
stringIteratorNext,
stringIteratorPrevious,
0
};
U_CAPI void U_EXPORT2
uiter_setString(UCharIterator *iter, const UChar *s, int32_t length) {
if(iter!=0) {
if(s!=0 && length>=-1) {
*iter=stringIterator;
iter->context=s;
if(length>=0) {
iter->length=length;
} else {
iter->length=u_strlen(s);
}
iter->limit=iter->length;
} else {
*iter=noopIterator;
}
}
}
/* UCharIterator wrapper around CharacterIterator --------------------------- */
/*
* This is wrapper code around a C++ CharacterIterator to
* look like a C UCharIterator.
*
* The UCharIterator.context field holds a pointer to the CharacterIterator.
*/
static int32_t U_CALLCONV
characterIteratorGetIndex(UCharIterator *iter, UCharIteratorOrigin origin) {
switch(origin) {
case UITER_ZERO:
return 0;
case UITER_START:
return ((CharacterIterator *)(iter->context))->startIndex();
case UITER_CURRENT:
return ((CharacterIterator *)(iter->context))->getIndex();
case UITER_LIMIT:
return ((CharacterIterator *)(iter->context))->endIndex();
case UITER_LENGTH:
return ((CharacterIterator *)(iter->context))->getLength();
default:
/* not a valid origin */
/* Should never get here! */
return -1;
}
}
static int32_t U_CALLCONV
characterIteratorMove(UCharIterator *iter, int32_t delta, UCharIteratorOrigin origin) {
switch(origin) {
case UITER_ZERO:
((CharacterIterator *)(iter->context))->setIndex(delta);
return ((CharacterIterator *)(iter->context))->getIndex();
case UITER_START:
case UITER_CURRENT:
case UITER_LIMIT:
return ((CharacterIterator *)(iter->context))->move(delta, (CharacterIterator::EOrigin)origin);
case UITER_LENGTH:
((CharacterIterator *)(iter->context))->setIndex(((CharacterIterator *)(iter->context))->getLength()+delta);
return ((CharacterIterator *)(iter->context))->getIndex();
default:
/* not a valid origin */
/* Should never get here! */
return -1;
}
}
static UBool U_CALLCONV
characterIteratorHasNext(UCharIterator *iter) {
return ((CharacterIterator *)(iter->context))->hasNext();
}
static UBool U_CALLCONV
characterIteratorHasPrevious(UCharIterator *iter) {
return ((CharacterIterator *)(iter->context))->hasPrevious();
}
static int32_t U_CALLCONV
characterIteratorCurrent(UCharIterator *iter) {
int32_t c;
c=((CharacterIterator *)(iter->context))->current();
if(c!=0xffff || ((CharacterIterator *)(iter->context))->hasNext()) {
return c;
} else {
return -1;
}
}
static int32_t U_CALLCONV
characterIteratorNext(UCharIterator *iter) {
if(((CharacterIterator *)(iter->context))->hasNext()) {
return ((CharacterIterator *)(iter->context))->nextPostInc();
} else {
return -1;
}
}
static int32_t U_CALLCONV
characterIteratorPrevious(UCharIterator *iter) {
if(((CharacterIterator *)(iter->context))->hasPrevious()) {
return ((CharacterIterator *)(iter->context))->previous();
} else {
return -1;
}
}
static const UCharIterator characterIteratorWrapper={
0, 0, 0, 0, 0, 0,
characterIteratorGetIndex,
characterIteratorMove,
characterIteratorHasNext,
characterIteratorHasPrevious,
characterIteratorCurrent,
characterIteratorNext,
characterIteratorPrevious,
0
};
U_CAPI void U_EXPORT2
uiter_setCharacterIterator(UCharIterator *iter, CharacterIterator *charIter) {
if(iter!=0) {
if(charIter!=0) {
*iter=characterIteratorWrapper;
iter->context=charIter;
} else {
*iter=noopIterator;
}
}
}
/* UCharIterator wrapper around Replaceable --------------------------------- */
/*
* This is an implementation of a code unit (UChar) iterator
* based on a Replaceable object.
*
* The UCharIterator.context field holds a pointer to the Replaceable.
* UCharIterator.length and UCharIterator.index hold Replaceable.length()
* and the iteration index.
*/
static int32_t U_CALLCONV
replaceableIteratorCurrent(UCharIterator *iter) {
if(iter->index<iter->limit) {
return ((Replaceable *)(iter->context))->charAt(iter->index);
} else {
return -1;
}
}
static int32_t U_CALLCONV
replaceableIteratorNext(UCharIterator *iter) {
if(iter->index<iter->limit) {
return ((Replaceable *)(iter->context))->charAt(iter->index++);
} else {
return -1;
}
}
static int32_t U_CALLCONV
replaceableIteratorPrevious(UCharIterator *iter) {
if(iter->index>iter->start) {
return ((Replaceable *)(iter->context))->charAt(--iter->index);
} else {
return -1;
}
}
static const UCharIterator replaceableIterator={
0, 0, 0, 0, 0, 0,
stringIteratorGetIndex,
stringIteratorMove,
stringIteratorHasNext,
stringIteratorHasPrevious,
replaceableIteratorCurrent,
replaceableIteratorNext,
replaceableIteratorPrevious,
0
};
U_CAPI void U_EXPORT2
uiter_setReplaceable(UCharIterator *iter, const Replaceable *rep) {
if(iter!=0) {
if(rep!=0) {
*iter=replaceableIterator;
iter->context=rep;
iter->limit=iter->length=rep->length();
} else {
*iter=noopIterator;
}
}
}
/* Helper functions --------------------------------------------------------- */
U_CAPI int32_t U_EXPORT2
uiter_current32(UCharIterator *iter) {
int32_t c, c2;
c=iter->current(iter);
if(UTF_IS_SURROGATE(c)) {
if(UTF_IS_SURROGATE_FIRST(c)) {
/*
* go to the next code unit
* we know that we are not at the limit because c!=-1
*/
iter->move(iter, 1, UITER_CURRENT);
if(UTF_IS_SECOND_SURROGATE(c2=iter->current(iter))) {
c=UTF16_GET_PAIR_VALUE(c, c2);
}
/* undo index movement */
iter->move(iter, -1, UITER_CURRENT);
} else {
if(UTF_IS_FIRST_SURROGATE(c2=iter->previous(iter))) {
c=UTF16_GET_PAIR_VALUE(c2, c);
}
if(c2>=0) {
/* undo index movement */
iter->move(iter, 1, UITER_CURRENT);
}
}
}
return c;
}
U_CAPI int32_t U_EXPORT2
uiter_next32(UCharIterator *iter) {
int32_t c, c2;
c=iter->next(iter);
if(UTF_IS_FIRST_SURROGATE(c)) {
if(UTF_IS_SECOND_SURROGATE(c2=iter->next(iter))) {
c=UTF16_GET_PAIR_VALUE(c, c2);
} else if(c2>=0) {
/* unmatched first surrogate, undo index movement */
iter->move(iter, -1, UITER_CURRENT);
}
}
return c;
}
U_CAPI int32_t U_EXPORT2
uiter_previous32(UCharIterator *iter) {
int32_t c, c2;
c=iter->previous(iter);
if(UTF_IS_SECOND_SURROGATE(c)) {
if(UTF_IS_FIRST_SURROGATE(c2=iter->previous(iter))) {
c=UTF16_GET_PAIR_VALUE(c2, c);
} else if(c2>=0) {
/* unmatched second surrogate, undo index movement */
iter->move(iter, 1, UITER_CURRENT);
}
}
return c;
}
U_CDECL_END