scuffed-code/icu4c/source/common/ustrcase.c
2002-02-21 17:58:51 +00:00

448 lines
13 KiB
C

/*
*******************************************************************************
*
* Copyright (C) 2001, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: ustrcase.c
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2002feb20
* created by: Markus W. Scherer
*
* Implementation file for string casing C API functions.
* Uses functions from uchar.c for basic functionality that requires access
* to the Unicode Character Database (uprops.dat).
*/
#include "unicode/utypes.h"
#include "unicode/ustring.h"
#include "unicode/ubrk.h"
#include "cmemory.h"
#include "ustr_imp.h"
/* string casing ------------------------------------------------------------ */
/*
* Internal titlecasing function,
* using u_internalStrToLower() and u_internalToTitle().
*
* Must get titleIter!=NULL.
*/
U_CFUNC int32_t
u_internalStrToTitle(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
UBreakIterator *titleIter,
const char *locale,
UErrorCode *pErrorCode) {
UCharIterator iter;
UChar32 c;
int32_t prev, index, destIndex, length;
UBool isFirstIndex;
/* set up local variables */
uiter_setString(&iter, src, srcLength);
destIndex=0;
prev=0;
isFirstIndex=TRUE;
/* titlecasing loop */
while(prev<srcLength) {
/* find next index where to titlecase */
if(isFirstIndex) {
isFirstIndex=FALSE;
index=ubrk_first(titleIter);
} else {
index=ubrk_next(titleIter);
}
if(index==UBRK_DONE || index>srcLength) {
index=srcLength;
}
/* lowercase [prev..index[ */
if(prev<index) {
if(destIndex<destCapacity) {
length=u_internalStrToLower(dest+destIndex, destCapacity-destIndex,
src, srcLength,
prev, index,
locale,
pErrorCode);
} else {
length=u_internalStrToLower(NULL, 0,
src, srcLength,
prev, index,
locale,
pErrorCode);
}
destIndex+=length;
}
if(index>=srcLength) {
break;
}
/* titlecase the character at the found index */
UTF_NEXT_CHAR(src, index, srcLength, c);
iter.move(&iter, index, UITER_START);
if(destIndex<destCapacity) {
length=u_internalToTitle(c, &iter,
dest+destIndex, destCapacity-destIndex,
locale);
} else {
length=u_internalToTitle(c, &iter, NULL, 0, locale);
}
if(length<0) {
length=-length;
}
destIndex+=length;
prev=index;
}
return destIndex;
}
/*
* Implement argument checking and buffer handling
* for string case mapping as a common function.
*/
enum {
TO_LOWER,
TO_UPPER,
TO_TITLE,
FOLD_CASE
};
static int32_t
u_strCaseMap(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
UBreakIterator *titleIter,
const char *locale,
uint32_t options,
int32_t toWhichCase,
UErrorCode *pErrorCode) {
UChar buffer[300];
UChar *temp;
int32_t destLength;
UBool ownTitleIter;
/* check argument values */
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
return 0;
}
if( destCapacity<0 ||
(dest==NULL && destCapacity>0) ||
src==NULL ||
srcLength<-1
) {
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
/* get the string length */
if(srcLength==-1) {
srcLength=u_strlen(src);
}
/* check for overlapping source and destination */
if( dest!=NULL &&
((src>=dest && src<(dest+destCapacity)) ||
(dest>=src && dest<(src+srcLength)))
) {
/* overlap: provide a temporary destination buffer and later copy the result */
if(destCapacity<=(sizeof(buffer)/U_SIZEOF_UCHAR)) {
/* the stack buffer is large enough */
temp=buffer;
} else {
/* allocate a buffer */
temp=(UChar *)uprv_malloc(destCapacity*U_SIZEOF_UCHAR);
if(temp==NULL) {
*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
return 0;
}
}
} else {
temp=dest;
}
ownTitleIter=FALSE;
if(toWhichCase==TO_LOWER) {
destLength=u_internalStrToLower(temp, destCapacity,
src, srcLength,
0, srcLength,
locale, pErrorCode);
} else if(toWhichCase==TO_UPPER) {
destLength=u_internalStrToUpper(temp, destCapacity, src, srcLength,
locale, pErrorCode);
} else if(toWhichCase==TO_TITLE) {
if(titleIter==NULL) {
/* ### TODO UBRK_TITLECASE */
titleIter=ubrk_open(UBRK_WORD, locale,
src, srcLength,
pErrorCode);
ownTitleIter=(UBool)U_SUCCESS(*pErrorCode);
}
if(U_SUCCESS(*pErrorCode)) {
destLength=u_internalStrToTitle(temp, destCapacity, src, srcLength,
titleIter, locale, pErrorCode);
}
} else {
destLength=u_internalStrFoldCase(temp, destCapacity, src, srcLength,
options, pErrorCode);
}
if(temp!=dest) {
/* copy the result string to the destination buffer */
if(destLength>0) {
uprv_memmove(dest, temp, destLength*U_SIZEOF_UCHAR);
}
if(temp!=buffer) {
uprv_free(temp);
}
}
if(ownTitleIter) {
ubrk_close(titleIter);
}
return u_terminateUChars(dest, destCapacity, destLength, pErrorCode);
}
U_CAPI int32_t U_EXPORT2
u_strToLower(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
const char *locale,
UErrorCode *pErrorCode) {
return u_strCaseMap(dest, destCapacity,
src, srcLength,
NULL, locale, 0,
TO_LOWER, pErrorCode);
}
U_CAPI int32_t U_EXPORT2
u_strToUpper(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
const char *locale,
UErrorCode *pErrorCode) {
return u_strCaseMap(dest, destCapacity,
src, srcLength,
NULL, locale, 0,
TO_UPPER, pErrorCode);
}
U_CAPI int32_t U_EXPORT2
u_strToTitle(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
UBreakIterator *titleIter,
const char *locale,
UErrorCode *pErrorCode) {
return u_strCaseMap(dest, destCapacity,
src, srcLength,
titleIter, locale, 0,
TO_TITLE, pErrorCode);
}
U_CAPI int32_t U_EXPORT2
u_strFoldCase(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
uint32_t options,
UErrorCode *pErrorCode) {
return u_strCaseMap(dest, destCapacity,
src, srcLength,
NULL, NULL, options,
FOLD_CASE, pErrorCode);
}
/* case-insensitive string comparisons */
U_CAPI int32_t U_EXPORT2
u_strcasecmp(const UChar *s1, const UChar *s2, uint32_t options) {
UChar t1[32], t2[32]; /* temporary buffers holding case-folded parts of s1 and s2 */
UChar32 c;
UChar uc;
int32_t pos1, pos2, len1, len2, result;
if(!uprv_haveProperties()) {
/* hardcode ASCII strcasecmp() */
UChar c1, c2;
for(;;) {
c1=*s1++;
if((uint16_t)(c1-0x41)<26) {
c1+=0x20;
}
c2=*s2++;
if((uint16_t)(c2-0x41)<26) {
c2+=0x20;
}
result=(int32_t)c1-(int32_t)c2;
if(result!=0 || c1==0) {
return result;
}
}
}
pos1=pos2=len1=len2=0;
for(;;) {
/* make sure that the temporary buffers are not empty */
if(pos1>=len1) {
c=*s1++;
if(c!=0) {
if(UTF_IS_FIRST_SURROGATE(c) && UTF_IS_SECOND_SURROGATE(uc=*s1)) {
c=UTF16_GET_PAIR_VALUE(c, uc);
++s1;
}
len1=u_internalFoldCase(c, t1, 32, options);
if(len1<0) {
len1=-len1;
}
pos1=0;
} else if(pos2>=len2 && *s2==0) {
return 0;
} else {
return -1;
}
}
if(pos2>=len2) {
c=*s2++;
if(c!=0) {
if(UTF_IS_FIRST_SURROGATE(c) && UTF_IS_SECOND_SURROGATE(uc=*s2)) {
c=UTF16_GET_PAIR_VALUE(c, uc);
++s2;
}
len2=u_internalFoldCase(c, t2, 32, options);
if(len2<0) {
len2=-len2;
}
pos2=0;
} else {
return 1;
}
}
/* compare the head code units from both folded strings */
result=(int32_t)t1[pos1++]-(int32_t)t2[pos2++];
if(result!=0) {
return result;
}
}
}
U_CFUNC int32_t
u_internalStrcasecmp(const UChar *s1, int32_t length1,
const UChar *s2, int32_t length2,
uint32_t options) {
UChar t1[32], t2[32]; /* temporary buffers holding case-folded parts of s1 and s2 */
UChar32 c;
UChar uc;
int32_t pos1, pos2, len1, len2, result;
if(!uprv_haveProperties()) {
/* hardcode ASCII strcasecmp() */
UChar c1, c2;
for(;;) {
if(length1<=0) {
if(length2<=0) {
return 0;
} else {
return -1;
}
} else if(length2<=0) {
return 1;
}
c1=*s1++;
if((uint16_t)(c1-0x41)<26) {
c1+=0x20;
}
c2=*s2++;
if((uint16_t)(c2-0x41)<26) {
c2+=0x20;
}
result=(int32_t)c1-(int32_t)c2;
if(result!=0) {
return result;
}
--length1;
--length2;
}
}
pos1=pos2=len1=len2=0;
for(;;) {
/* make sure that the temporary buffers are not empty */
if(pos1>=len1) {
if(length1>0) {
c=*s1++;
if(UTF_IS_FIRST_SURROGATE(c) && length1>1 && UTF_IS_SECOND_SURROGATE(uc=*s1)) {
c=UTF16_GET_PAIR_VALUE(c, uc);
++s1;
length1-=2;
} else {
--length1;
}
len1=u_internalFoldCase(c, t1, 32, options);
if(len1<0) {
len1=-len1;
}
pos1=0;
} else if(pos2>=len2 && length2<=0) {
return 0;
} else {
return -1;
}
}
if(pos2>=len2) {
if(length2>0) {
c=*s2++;
if(UTF_IS_FIRST_SURROGATE(c) && length2>1 && UTF_IS_SECOND_SURROGATE(uc=*s2)) {
c=UTF16_GET_PAIR_VALUE(c, uc);
++s2;
length2-=2;
} else {
--length2;
}
len2=u_internalFoldCase(c, t2, 32, options);
if(len2<0) {
len2=-len2;
}
pos2=0;
} else {
return 1;
}
}
/* compare the head code units from both folded strings */
result=(int32_t)t1[pos1++]-(int32_t)t2[pos2++];
if(result!=0) {
return result;
}
}
}
U_CAPI int32_t U_EXPORT2
u_memcasecmp(const UChar *s1, const UChar *s2, int32_t length, uint32_t options) {
return u_internalStrcasecmp(s1, length, s2, length, options);
}
U_CAPI int32_t U_EXPORT2
u_strncasecmp(const UChar *s1, const UChar *s2, int32_t n, uint32_t options) {
/*
* This is a simple, sub-optimal implementation:
* Determine the actual lengths of the strings and call u_internalStrcasecmp().
* This saves us from having an additional variant of the above strcasecmp().
*/
const UChar *s;
int32_t length1, length2;
for(s=s1, length1=0; length1<n && *s!=0; ++s, ++length1) {}
for(s=s2, length2=0; length2<n && *s!=0; ++s, ++length2) {}
return u_internalStrcasecmp(s1, length1, s2, length2, options);
}