godot/thirdparty/icu4c/common/ustr_imp.h

156 lines
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C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
**********************************************************************
* Copyright (C) 1999-2015, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
* file name: ustr_imp.h
* encoding: UTF-8
* tab size: 8 (not used)
* indentation:4
*
* created on: 2001jan30
* created by: Markus W. Scherer
*/
#ifndef __USTR_IMP_H__
#define __USTR_IMP_H__
#include "unicode/utypes.h"
#include "unicode/utf8.h"
/**
* Internal option for unorm_cmpEquivFold() for strncmp style.
* If set, checks for both string length and terminating NUL.
*/
#define _STRNCMP_STYLE 0x1000
/**
* Compare two strings in code point order or code unit order.
* Works in strcmp style (both lengths -1),
* strncmp style (lengths equal and >=0, flag true),
* and memcmp/UnicodeString style (at least one length >=0).
*/
U_CFUNC int32_t U_EXPORT2
uprv_strCompare(const UChar *s1, int32_t length1,
const UChar *s2, int32_t length2,
UBool strncmpStyle, UBool codePointOrder);
U_CAPI int32_t U_EXPORT2
ustr_hashUCharsN(const UChar *str, int32_t length);
U_CAPI int32_t U_EXPORT2
ustr_hashCharsN(const char *str, int32_t length);
U_CAPI int32_t U_EXPORT2
ustr_hashICharsN(const char *str, int32_t length);
/**
* Convert an ASCII-range lowercase character to uppercase.
*
* @param c A UChar.
* @return If UChar is a lowercase ASCII character, returns the uppercase version.
* Otherwise, returns the input character.
*/
U_CAPI UChar U_EXPORT2
u_asciiToUpper(UChar c);
// TODO: Add u_asciiToLower if/when there is a need for it.
/**
* NUL-terminate a UChar * string if possible.
* If length < destCapacity then NUL-terminate.
* If length == destCapacity then do not terminate but set U_STRING_NOT_TERMINATED_WARNING.
* If length > destCapacity then do not terminate but set U_BUFFER_OVERFLOW_ERROR.
*
* @param dest Destination buffer, can be NULL if destCapacity==0.
* @param destCapacity Number of UChars available at dest.
* @param length Number of UChars that were (to be) written to dest.
* @param pErrorCode ICU error code.
* @return length
*/
U_CAPI int32_t U_EXPORT2
u_terminateUChars(UChar *dest, int32_t destCapacity, int32_t length, UErrorCode *pErrorCode);
/**
* NUL-terminate a char * string if possible.
* Same as u_terminateUChars() but for a different string type.
*/
U_CAPI int32_t U_EXPORT2
u_terminateChars(char *dest, int32_t destCapacity, int32_t length, UErrorCode *pErrorCode);
/**
* NUL-terminate a UChar32 * string if possible.
* Same as u_terminateUChars() but for a different string type.
*/
U_CAPI int32_t U_EXPORT2
u_terminateUChar32s(UChar32 *dest, int32_t destCapacity, int32_t length, UErrorCode *pErrorCode);
/**
* NUL-terminate a wchar_t * string if possible.
* Same as u_terminateUChars() but for a different string type.
*/
U_CAPI int32_t U_EXPORT2
u_terminateWChars(wchar_t *dest, int32_t destCapacity, int32_t length, UErrorCode *pErrorCode);
/**
* Counts the bytes of any whole valid sequence for a UTF-8 lead byte.
* Returns 1 for ASCII 0..0x7f.
* Returns 0 for 0x80..0xc1 as well as for 0xf5..0xff.
* leadByte might be evaluated multiple times.
*
* @param leadByte The first byte of a UTF-8 sequence. Must be 0..0xff.
* @return 0..4
*/
#define U8_COUNT_BYTES(leadByte) \
(U8_IS_SINGLE(leadByte) ? 1 : U8_COUNT_BYTES_NON_ASCII(leadByte))
/**
* Counts the bytes of any whole valid sequence for a UTF-8 lead byte.
* Returns 0 for 0x00..0xc1 as well as for 0xf5..0xff.
* leadByte might be evaluated multiple times.
*
* @param leadByte The first byte of a UTF-8 sequence. Must be 0..0xff.
* @return 0 or 2..4
*/
#define U8_COUNT_BYTES_NON_ASCII(leadByte) \
(U8_IS_LEAD(leadByte) ? ((uint8_t)(leadByte)>=0xe0)+((uint8_t)(leadByte)>=0xf0)+2 : 0)
#ifdef __cplusplus
U_NAMESPACE_BEGIN
class UTF8 {
public:
UTF8() = delete; // all static
/**
* Is t a valid UTF-8 trail byte?
*
* @param prev Must be the preceding lead byte if i==1 and length>=3;
* otherwise ignored.
* @param t The i-th byte following the lead byte.
* @param i The index (1..3) of byte t in the byte sequence. 0<i<length
* @param length The length (2..4) of the byte sequence according to the lead byte.
* @return true if t is a valid trail byte in this context.
*/
static inline UBool isValidTrail(int32_t prev, uint8_t t, int32_t i, int32_t length) {
// The first trail byte after a 3- or 4-byte lead byte
// needs to be validated together with its lead byte.
if (length <= 2 || i > 1) {
return U8_IS_TRAIL(t);
} else if (length == 3) {
return U8_IS_VALID_LEAD3_AND_T1(prev, t);
} else { // length == 4
return U8_IS_VALID_LEAD4_AND_T1(prev, t);
}
}
};
U_NAMESPACE_END
#endif // __cplusplus
#endif