scuffed-code/icu4c/source/common/unorm_it.c
Markus Scherer e3bb8d9a00 ICU-2397 avoid memset for faster setup
X-SVN-Rev: 11814
2003-05-06 18:52:28 +00:00

647 lines
19 KiB
C

/*
*******************************************************************************
*
* Copyright (C) 2003, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: unorm_it.c
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2003jan21
* created by: Markus W. Scherer
*/
#include "unicode/utypes.h"
#if !UCONFIG_NO_COLLATION && !UCONFIG_NO_NORMALIZATION
#include "unicode/uiter.h"
#include "unicode/unorm.h"
#include "unorm_it.h"
#include "cmemory.h"
/* UNormIterator ------------------------------------------------------------ */
enum {
INITIAL_CAPACITY=100
};
struct UNormIterator {
UCharIterator api;
UCharIterator *iter;
/*
* chars and states either use the static buffers
* or are allocated in the same memory block
*
* They are parallel arrays with states[] holding the getState() values
* from normalization boundaries, and UITER_NO_STATE in between.
*/
UChar *chars;
uint32_t *states;
/*
* api.start: first valid character & state in the arrays
* api.index: current position
* api.limit: one past the last valid character in chars[], but states[limit] is valid
* capacity: length of allocated arrays
*/
int32_t capacity;
/* the current iter->getState(), saved to avoid unnecessary setState() calls; may not correspond to api->index! */
uint32_t state;
/* there are UChars available before start or after limit? */
UBool hasPrevious, hasNext, isStackAllocated;
UNormalizationMode mode;
UChar charsBuffer[INITIAL_CAPACITY];
uint32_t statesBuffer[INITIAL_CAPACITY+1]; /* one more than charsBuffer[]! */
};
static void
initIndexes(UNormIterator *uni, UCharIterator *iter) {
/* do not pass api so that the compiler knows it's an alias pointer to uni itself */
UCharIterator *api=&uni->api;
if(!iter->hasPrevious(iter)) {
/* set indexes to the beginning of the arrays */
api->start=api->index=api->limit=0;
uni->hasPrevious=FALSE;
uni->hasNext=iter->hasNext(iter);
} else if(!iter->hasNext(iter)) {
/* set indexes to the end of the arrays */
api->start=api->index=api->limit=uni->capacity;
uni->hasNext=FALSE;
uni->hasPrevious=iter->hasPrevious(iter);
} else {
/* set indexes into the middle of the arrays */
api->start=api->index=api->limit=uni->capacity/2;
uni->hasPrevious=uni->hasNext=TRUE;
}
}
static UBool
reallocArrays(UNormIterator *uni, int32_t capacity, UBool addAtStart) {
/* do not pass api so that the compiler knows it's an alias pointer to uni itself */
UCharIterator *api=&uni->api;
uint32_t *states;
UChar *chars;
int32_t start, limit;
states=(uint32_t *)uprv_malloc((capacity+1)*4+capacity*2);
if(states==NULL) {
return FALSE;
}
chars=(UChar *)(states+(capacity+1));
uni->capacity=capacity;
start=api->start;
limit=api->limit;
if(addAtStart) {
/* copy old contents to the end of the new arrays */
int32_t delta;
delta=capacity-uni->capacity;
uprv_memcpy(states+delta+start, uni->states+start, (limit-start+1)*4);
uprv_memcpy(chars+delta+start, uni->chars+start, (limit-start)*4);
api->start=start+delta;
api->index+=delta;
api->limit=limit+delta;
} else {
/* copy old contents to the beginning of the new arrays */
uprv_memcpy(states+start, uni->states+start, (limit-start+1)*4);
uprv_memcpy(chars+start, uni->chars+start, (limit-start)*4);
}
uni->chars=chars;
uni->states=states;
return TRUE;
}
static void
moveContentsTowardStart(UCharIterator *api, UChar chars[], uint32_t states[], int32_t delta) {
/* move array contents up to make room */
int32_t srcIndex, destIndex, limit;
limit=api->limit;
srcIndex=delta;
if(srcIndex>api->start) {
/* look for a position in the arrays with a known state */
while(srcIndex<limit && chars[srcIndex]==UITER_NO_STATE) {
++srcIndex;
}
}
/* now actually move the array contents */
api->start=destIndex=0;
while(srcIndex<limit) {
chars[destIndex]=chars[srcIndex];
states[destIndex++]=states[srcIndex++];
}
/* copy states[limit] as well! */
states[destIndex]=states[srcIndex];
api->limit=destIndex;
}
static void
moveContentsTowardEnd(UCharIterator *api, UChar chars[], uint32_t states[], int32_t delta) {
/* move array contents up to make room */
int32_t srcIndex, destIndex, start;
start=api->start;
destIndex=((UNormIterator *)api)->capacity;
srcIndex=destIndex-delta;
if(srcIndex<api->limit) {
/* look for a position in the arrays with a known state */
while(srcIndex>start && chars[srcIndex]==UITER_NO_STATE) {
--srcIndex;
}
}
/* now actually move the array contents */
api->limit=destIndex;
/* copy states[limit] as well! */
states[destIndex]=states[srcIndex];
while(srcIndex>start) {
chars[--destIndex]=chars[--srcIndex];
states[destIndex]=states[srcIndex];
}
api->start=destIndex;
}
/* normalize forward from the limit, assume hasNext is true */
static UBool
readNext(UNormIterator *uni, UCharIterator *iter) {
/* do not pass api so that the compiler knows it's an alias pointer to uni itself */
UCharIterator *api=&uni->api;
/* make capacity/4 room at the end of the arrays */
int32_t limit, capacity, room, delta;
UErrorCode errorCode;
limit=api->limit;
capacity=uni->capacity;
room=capacity/4;
delta=room-(capacity-limit);
if(delta>0) {
/* move array contents to make room */
moveContentsTowardStart(api, uni->chars, uni->states, delta);
api->index=limit=api->limit;
uni->hasPrevious=TRUE;
}
/* normalize starting from the limit position */
errorCode=U_ZERO_ERROR;
if(uni->state!=uni->states[limit]) {
uiter_setState(iter, uni->states[limit], &errorCode);
if(U_FAILURE(errorCode)) {
uni->state=UITER_NO_STATE;
uni->hasNext=FALSE;
return FALSE;
}
}
room=unorm_next(iter, uni->chars+limit, capacity-limit, uni->mode, 0, TRUE, NULL, &errorCode);
if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
if(room<=capacity) {
/* empty and re-use the arrays */
uni->states[0]=uni->states[limit];
api->start=api->index=api->limit=limit=0;
uni->hasPrevious=TRUE;
} else {
capacity+=room+100;
if(!reallocArrays(uni, capacity, FALSE)) {
uni->state=UITER_NO_STATE;
uni->hasNext=FALSE;
return FALSE;
}
limit=api->limit;
}
errorCode=U_ZERO_ERROR;
uiter_setState(iter, uni->states[limit], &errorCode);
room=unorm_next(iter, uni->chars+limit, capacity-limit, uni->mode, 0, TRUE, NULL, &errorCode);
}
if(U_FAILURE(errorCode) || room==0) {
uni->state=UITER_NO_STATE;
uni->hasNext=FALSE;
return FALSE;
}
/* room>0 */
++limit; /* leave the known states[limit] alone */
for(--room; room>0; --room) {
/* set unknown states for all but the normalization boundaries */
uni->states[limit++]=UITER_NO_STATE;
}
uni->states[limit]=uni->state=uiter_getState(iter);
uni->hasNext=iter->hasNext(iter);
api->limit=limit;
return TRUE;
}
/* normalize backward from the start, assume hasPrevious is true */
static UBool
readPrevious(UNormIterator *uni, UCharIterator *iter) {
/* do not pass api so that the compiler knows it's an alias pointer to uni itself */
UCharIterator *api=&uni->api;
/* make capacity/4 room at the start of the arrays */
int32_t start, capacity, room, delta;
UErrorCode errorCode;
start=api->start;
capacity=uni->capacity;
room=capacity/4;
delta=room-start;
if(delta>0) {
/* move array contents to make room */
moveContentsTowardEnd(api, uni->chars, uni->states, delta);
api->index=start=api->start;
uni->hasNext=TRUE;
}
/* normalize ending at the start position */
errorCode=U_ZERO_ERROR;
if(uni->state!=uni->states[start]) {
uiter_setState(iter, uni->states[start], &errorCode);
if(U_FAILURE(errorCode)) {
uni->state=UITER_NO_STATE;
uni->hasPrevious=FALSE;
return FALSE;
}
}
room=unorm_previous(iter, uni->chars, start, uni->mode, 0, TRUE, NULL, &errorCode);
if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
if(room<=capacity) {
/* empty and re-use the arrays */
uni->states[capacity]=uni->states[start];
api->start=api->index=api->limit=start=capacity;
uni->hasNext=TRUE;
} else {
capacity+=room+100;
if(!reallocArrays(uni, capacity, TRUE)) {
uni->state=UITER_NO_STATE;
uni->hasPrevious=FALSE;
return FALSE;
}
start=api->start;
}
errorCode=U_ZERO_ERROR;
uiter_setState(iter, uni->states[start], &errorCode);
room=unorm_previous(iter, uni->chars, start, uni->mode, 0, TRUE, NULL, &errorCode);
}
if(U_FAILURE(errorCode) || room==0) {
uni->state=UITER_NO_STATE;
uni->hasPrevious=FALSE;
return FALSE;
}
/* room>0 */
do {
/* copy the UChars from chars[0..room[ to chars[(start-room)..start[ */
uni->chars[--start]=uni->chars[--room];
/* set unknown states for all but the normalization boundaries */
uni->states[start]=UITER_NO_STATE;
} while(room>0);
uni->states[start]=uni->state=uiter_getState(iter);
uni->hasPrevious=iter->hasPrevious(iter);
api->start=start;
return TRUE;
}
/* Iterator runtime API functions ------------------------------------------- */
static int32_t U_CALLCONV
unormIteratorGetIndex(UCharIterator *api, UCharIteratorOrigin origin) {
switch(origin) {
case UITER_ZERO:
case UITER_START:
return 0;
case UITER_CURRENT:
case UITER_LIMIT:
case UITER_LENGTH:
return UITER_UNKNOWN_INDEX;
default:
/* not a valid origin */
/* Should never get here! */
return -1;
}
}
static int32_t U_CALLCONV
unormIteratorMove(UCharIterator *api, int32_t delta, UCharIteratorOrigin origin) {
UNormIterator *uni=(UNormIterator *)api;
UCharIterator *iter=uni->iter;
int32_t pos;
switch(origin) {
case UITER_ZERO:
case UITER_START:
/* restart from the beginning */
if(uni->hasPrevious) {
iter->move(iter, 0, UITER_START);
api->start=api->index=api->limit=0;
uni->states[api->limit]=uni->state=uiter_getState(iter);
uni->hasPrevious=FALSE;
uni->hasNext=iter->hasNext(iter);
} else {
/* we already have the beginning of the normalized text */
api->index=api->start;
}
break;
case UITER_CURRENT:
break;
case UITER_LIMIT:
case UITER_LENGTH:
/* restart from the end */
if(uni->hasNext) {
iter->move(iter, 0, UITER_LIMIT);
api->start=api->index=api->limit=uni->capacity;
uni->states[api->limit]=uni->state=uiter_getState(iter);
uni->hasPrevious=iter->hasPrevious(iter);
uni->hasNext=FALSE;
} else {
/* we already have the end of the normalized text */
api->index=api->limit;
}
break;
default:
return -1; /* Error */
}
/* move relative to the current position by delta normalized UChars */
if(delta==0) {
/* nothing to do */
} else if(delta>0) {
/* go forward until the requested position is in the buffer */
for(;;) {
pos=api->index+delta; /* requested position */
delta=pos-api->limit; /* remainder beyond buffered text */
if(delta<=0) {
api->index=pos; /* position reached */
break;
}
/* go to end of buffer and normalize further */
api->index=api->limit;
if(!uni->hasNext || !readNext(uni, iter)) {
break; /* reached end of text */
}
}
} else /* delta<0 */ {
/* go backward until the requested position is in the buffer */
for(;;) {
pos=api->index+delta; /* requested position */
delta=pos-api->start; /* remainder beyond buffered text */
if(delta>=0) {
api->index=pos; /* position reached */
break;
}
/* go to start of buffer and normalize further */
api->index=api->start;
if(!uni->hasPrevious || !readPrevious(uni, iter)) {
break; /* reached start of text */
}
}
}
if(api->index==api->start && !uni->hasPrevious) {
return 0;
} else {
return UITER_UNKNOWN_INDEX;
}
}
static UBool U_CALLCONV
unormIteratorHasNext(UCharIterator *api) {
return api->index<api->limit || ((UNormIterator *)api)->hasNext;
}
static UBool U_CALLCONV
unormIteratorHasPrevious(UCharIterator *api) {
return api->index>api->start || ((UNormIterator *)api)->hasPrevious;
}
static UChar32 U_CALLCONV
unormIteratorCurrent(UCharIterator *api) {
UNormIterator *uni=(UNormIterator *)api;
if( api->index<api->limit ||
(uni->hasNext && readNext(uni, uni->iter))
) {
return uni->chars[api->index];
} else {
return U_SENTINEL;
}
}
static UChar32 U_CALLCONV
unormIteratorNext(UCharIterator *api) {
UNormIterator *uni=(UNormIterator *)api;
if( api->index<api->limit ||
(uni->hasNext && readNext(uni, uni->iter))
) {
return uni->chars[api->index++];
} else {
return U_SENTINEL;
}
}
static UChar32 U_CALLCONV
unormIteratorPrevious(UCharIterator *api) {
UNormIterator *uni=(UNormIterator *)api;
if( api->index>api->start ||
(uni->hasPrevious && readPrevious(uni, uni->iter))
) {
return uni->chars[--api->index];
} else {
return U_SENTINEL;
}
}
static uint32_t U_CALLCONV
unormIteratorGetState(const UCharIterator *api) {
/* not uni->state because that may not be at api->index */
return ((UNormIterator *)api)->states[api->index];
}
static void U_CALLCONV
unormIteratorSetState(UCharIterator *api, uint32_t state, UErrorCode *pErrorCode) {
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
/* do nothing */
} else if(api==NULL) {
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
} else if(state==UITER_NO_STATE) {
*pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
} else {
UNormIterator *uni=(UNormIterator *)api;
UCharIterator *iter=((UNormIterator *)api)->iter;
if(state!=uni->state) {
uni->state=state;
uiter_setState(iter, state, pErrorCode);
}
/*
* Try shortcuts: If the requested state is in the array contents
* then just set the index there.
*
* We assume that the state is unique per position!
*/
if(state==uni->states[api->index]) {
return;
} else if(state==uni->states[api->limit]) {
api->index=api->limit;
return;
} else {
/* search for the index with this state */
int32_t i;
for(i=api->start; i<api->limit; ++i) {
if(state==uni->states[i]) {
api->index=i;
return;
}
}
}
/* there is no array index for this state, reset for fresh contents */
initIndexes((UNormIterator *)api, iter);
uni->states[api->limit]=state;
}
}
static const UCharIterator unormIterator={
NULL, 0, 0, 0, 0, 0,
unormIteratorGetIndex,
unormIteratorMove,
unormIteratorHasNext,
unormIteratorHasPrevious,
unormIteratorCurrent,
unormIteratorNext,
unormIteratorPrevious,
NULL,
unormIteratorGetState,
unormIteratorSetState
};
/* Setup functions ---------------------------------------------------------- */
U_CAPI UNormIterator * U_EXPORT2
unorm_openIter(void *stackMem, int32_t stackMemSize, UErrorCode *pErrorCode) {
UNormIterator *uni;
/* argument checking */
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
return NULL;
}
/* allocate */
uni=NULL;
if(stackMem!=NULL && stackMemSize>=sizeof(UNormIterator)) {
size_t align=U_ALIGNMENT_OFFSET(stackMem);
if(align==0) {
/* already aligned */
uni=(UNormIterator *)stackMem;
} else if((stackMemSize-=align)>=sizeof(UNormIterator)) {
/* needs alignment */
uni=(UNormIterator *)((char *)stackMem+align);
} else {
/* does not fit */
}
}
if(uni!=NULL) {
uni->isStackAllocated=TRUE;
} else {
uni=(UNormIterator *)uprv_malloc(sizeof(UNormIterator));
if(uni==NULL) {
*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
return NULL;
}
uni->isStackAllocated=FALSE;
}
/*
* initialize
* do not memset because that would unnecessarily initialize the arrays
*/
uni->iter=NULL;
uni->chars=uni->charsBuffer;
uni->states=uni->statesBuffer;
uni->capacity=INITIAL_CAPACITY;
uni->state=UITER_NO_STATE;
uni->hasPrevious=uni->hasNext=FALSE;
uni->mode=UNORM_NONE;
/* set a no-op iterator into the api */
uiter_setString(&uni->api, NULL, 0);
return uni;
}
U_CAPI void U_EXPORT2
unorm_closeIter(UNormIterator *uni) {
if(uni!=NULL) {
if(uni->states!=uni->statesBuffer) {
/* chars and states are allocated in the same memory block */
uprv_free(uni->states);
}
if(!uni->isStackAllocated) {
uprv_free(uni);
}
}
}
U_CAPI UCharIterator * U_EXPORT2
unorm_setIter(UNormIterator *uni, UCharIterator *iter, UNormalizationMode mode, UErrorCode *pErrorCode) {
/* argument checking */
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
return NULL;
}
if(uni==NULL) {
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
return NULL;
}
if( iter==NULL || iter->getState==NULL || iter->setState==NULL ||
mode<UNORM_NONE || UNORM_MODE_COUNT<=mode
) {
/* set a no-op iterator into the api */
uiter_setString(&uni->api, NULL, 0);
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
return NULL;
}
/* set the iterator and initialize */
uprv_memcpy(&uni->api, &unormIterator, sizeof(unormIterator));
uni->iter=iter;
uni->mode=mode;
initIndexes(uni, iter);
uni->states[uni->api.limit]=uni->state=uiter_getState(iter);
return &uni->api;
}
#endif /* uconfig.h switches */