godot/thirdparty/icu4c/common/bytesinkutil.h

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

157 lines
5.7 KiB
C++
Raw Normal View History

// © 2017 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
// bytesinkutil.h
// created: 2017sep14 Markus W. Scherer
2022-10-28 06:11:55 +00:00
#ifndef BYTESINKUTIL_H
#define BYTESINKUTIL_H
2024-05-14 08:41:19 +00:00
#include <type_traits>
#include "unicode/utypes.h"
#include "unicode/bytestream.h"
#include "unicode/edits.h"
2024-05-14 08:41:19 +00:00
#include "charstr.h"
#include "cmemory.h"
#include "uassert.h"
2024-05-14 08:41:19 +00:00
#include "ustr_imp.h"
U_NAMESPACE_BEGIN
class ByteSink;
class Edits;
2024-05-14 08:41:19 +00:00
class U_COMMON_API CharStringByteSink : public ByteSink {
public:
CharStringByteSink(CharString* dest);
~CharStringByteSink() override;
CharStringByteSink() = delete;
CharStringByteSink(const CharStringByteSink&) = delete;
CharStringByteSink& operator=(const CharStringByteSink&) = delete;
void Append(const char* bytes, int32_t n) override;
char* GetAppendBuffer(int32_t min_capacity,
int32_t desired_capacity_hint,
char* scratch,
int32_t scratch_capacity,
int32_t* result_capacity) override;
private:
CharString& dest_;
};
// CharString doesn't provide the public API that StringByteSink requires a
// string class to have so this template specialization replaces the default
// implementation of StringByteSink<CharString> with CharStringByteSink.
template<>
class StringByteSink<CharString> : public CharStringByteSink {
public:
StringByteSink(CharString* dest) : CharStringByteSink(dest) { }
StringByteSink(CharString* dest, int32_t /*initialAppendCapacity*/) : CharStringByteSink(dest) { }
};
class U_COMMON_API ByteSinkUtil {
public:
ByteSinkUtil() = delete; // all static
/** (length) bytes were mapped to valid (s16, s16Length). */
static UBool appendChange(int32_t length,
const char16_t *s16, int32_t s16Length,
ByteSink &sink, Edits *edits, UErrorCode &errorCode);
/** The bytes at [s, limit[ were mapped to valid (s16, s16Length). */
static UBool appendChange(const uint8_t *s, const uint8_t *limit,
const char16_t *s16, int32_t s16Length,
ByteSink &sink, Edits *edits, UErrorCode &errorCode);
/** (length) bytes were mapped/changed to valid code point c. */
static void appendCodePoint(int32_t length, UChar32 c, ByteSink &sink, Edits *edits = nullptr);
/** The few bytes at [src, nextSrc[ were mapped/changed to valid code point c. */
static inline void appendCodePoint(const uint8_t *src, const uint8_t *nextSrc, UChar32 c,
ByteSink &sink, Edits *edits = nullptr) {
appendCodePoint((int32_t)(nextSrc - src), c, sink, edits);
}
/** Append the two-byte character (U+0080..U+07FF). */
static void appendTwoBytes(UChar32 c, ByteSink &sink);
static UBool appendUnchanged(const uint8_t *s, int32_t length,
ByteSink &sink, uint32_t options, Edits *edits,
UErrorCode &errorCode) {
if (U_FAILURE(errorCode)) { return false; }
if (length > 0) { appendNonEmptyUnchanged(s, length, sink, options, edits); }
return true;
}
static UBool appendUnchanged(const uint8_t *s, const uint8_t *limit,
ByteSink &sink, uint32_t options, Edits *edits,
UErrorCode &errorCode);
2024-05-14 08:41:19 +00:00
/**
* Calls a lambda that writes to a ByteSink with a CheckedArrayByteSink
* and then returns through u_terminateChars(), in order to implement
* the classic ICU4C C API writing to a fix sized buffer on top of a
* contemporary C++ API.
*
* @param buffer receiving buffer
* @param capacity capacity of receiving buffer
* @param lambda that gets called with the sink as an argument
* @param status set to U_BUFFER_OVERFLOW_ERROR on overflow
* @return number of bytes written, or needed (in case of overflow)
* @internal
*/
template <typename F,
typename = std::enable_if_t<
std::is_invocable_r_v<void, F, ByteSink&, UErrorCode&>>>
static int32_t viaByteSinkToTerminatedChars(char* buffer, int32_t capacity,
F&& lambda,
UErrorCode& status) {
if (U_FAILURE(status)) { return 0; }
CheckedArrayByteSink sink(buffer, capacity);
lambda(sink, status);
if (U_FAILURE(status)) { return 0; }
int32_t reslen = sink.NumberOfBytesAppended();
if (sink.Overflowed()) {
status = U_BUFFER_OVERFLOW_ERROR;
return reslen;
}
return u_terminateChars(buffer, capacity, reslen, &status);
}
2024-05-14 08:41:19 +00:00
/**
* Calls a lambda that writes to a ByteSink with a CharStringByteSink and
* then returns a CharString, in order to implement a contemporary C++ API
* on top of a C/C++ compatibility ByteSink API.
*
* @param lambda that gets called with the sink as an argument
* @param status to check and report
* @return the resulting string, or an empty string (in case of error)
* @internal
*/
template <typename F,
typename = std::enable_if_t<
std::is_invocable_r_v<void, F, ByteSink&, UErrorCode&>>>
static CharString viaByteSinkToCharString(F&& lambda, UErrorCode& status) {
if (U_FAILURE(status)) { return {}; }
CharString result;
CharStringByteSink sink(&result);
lambda(sink, status);
return result;
}
private:
2024-05-14 08:41:19 +00:00
static void appendNonEmptyUnchanged(const uint8_t *s, int32_t length,
ByteSink &sink, uint32_t options, Edits *edits);
};
U_NAMESPACE_END
2022-10-28 06:11:55 +00:00
#endif //BYTESINKUTIL_H