llvm-6502/lib/Support/ConvertUTFWrapper.cpp
Reid Kleckner 06c847e83e [Support] Add a Unicode conversion wrapper from UTF16 to UTF8
This is to support parsing UTF16 response files in LLVM/lib/Option for
lld and clang.

Reviewers: hans

Differential Revision: http://llvm-reviews.chandlerc.com/D1138

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186426 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-16 17:14:33 +00:00

132 lines
4.4 KiB
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//===-- ConvertUTFWrapper.cpp - Wrap ConvertUTF.h with clang data types -----===
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/ConvertUTF.h"
#include "llvm/Support/SwapByteOrder.h"
#include <string>
#include <vector>
namespace llvm {
bool ConvertUTF8toWide(unsigned WideCharWidth, llvm::StringRef Source,
char *&ResultPtr, const UTF8 *&ErrorPtr) {
assert(WideCharWidth == 1 || WideCharWidth == 2 || WideCharWidth == 4);
ConversionResult result = conversionOK;
// Copy the character span over.
if (WideCharWidth == 1) {
const UTF8 *Pos = reinterpret_cast<const UTF8*>(Source.begin());
if (!isLegalUTF8String(&Pos, reinterpret_cast<const UTF8*>(Source.end()))) {
result = sourceIllegal;
ErrorPtr = Pos;
} else {
memcpy(ResultPtr, Source.data(), Source.size());
ResultPtr += Source.size();
}
} else if (WideCharWidth == 2) {
const UTF8 *sourceStart = (const UTF8*)Source.data();
// FIXME: Make the type of the result buffer correct instead of
// using reinterpret_cast.
UTF16 *targetStart = reinterpret_cast<UTF16*>(ResultPtr);
ConversionFlags flags = strictConversion;
result = ConvertUTF8toUTF16(
&sourceStart, sourceStart + Source.size(),
&targetStart, targetStart + 2*Source.size(), flags);
if (result == conversionOK)
ResultPtr = reinterpret_cast<char*>(targetStart);
else
ErrorPtr = sourceStart;
} else if (WideCharWidth == 4) {
const UTF8 *sourceStart = (const UTF8*)Source.data();
// FIXME: Make the type of the result buffer correct instead of
// using reinterpret_cast.
UTF32 *targetStart = reinterpret_cast<UTF32*>(ResultPtr);
ConversionFlags flags = strictConversion;
result = ConvertUTF8toUTF32(
&sourceStart, sourceStart + Source.size(),
&targetStart, targetStart + 4*Source.size(), flags);
if (result == conversionOK)
ResultPtr = reinterpret_cast<char*>(targetStart);
else
ErrorPtr = sourceStart;
}
assert((result != targetExhausted)
&& "ConvertUTF8toUTFXX exhausted target buffer");
return result == conversionOK;
}
bool ConvertCodePointToUTF8(unsigned Source, char *&ResultPtr) {
const UTF32 *SourceStart = &Source;
const UTF32 *SourceEnd = SourceStart + 1;
UTF8 *TargetStart = reinterpret_cast<UTF8 *>(ResultPtr);
UTF8 *TargetEnd = TargetStart + 4;
ConversionResult CR = ConvertUTF32toUTF8(&SourceStart, SourceEnd,
&TargetStart, TargetEnd,
strictConversion);
if (CR != conversionOK)
return false;
ResultPtr = reinterpret_cast<char*>(TargetStart);
return true;
}
bool hasUTF16ByteOrderMark(ArrayRef<char> S) {
return (S.size() >= 2 &&
((S[0] == '\xff' && S[1] == '\xfe') ||
(S[0] == '\xfe' && S[1] == '\xff')));
}
bool convertUTF16ToUTF8String(ArrayRef<char> SrcBytes, std::string &Out) {
assert(Out.empty());
// Error out on an uneven byte count.
if (SrcBytes.size() % 2)
return false;
// Avoid OOB by returning early on empty input.
if (SrcBytes.empty())
return true;
const UTF16 *Src = reinterpret_cast<const UTF16 *>(SrcBytes.begin());
const UTF16 *SrcEnd = reinterpret_cast<const UTF16 *>(SrcBytes.end());
// Byteswap if necessary.
std::vector<UTF16> ByteSwapped;
if (Src[0] == UNI_UTF16_BYTE_ORDER_MARK_SWAPPED) {
ByteSwapped.insert(ByteSwapped.end(), Src, SrcEnd);
for (unsigned I = 0, E = ByteSwapped.size(); I != E; ++I)
ByteSwapped[I] = llvm::sys::SwapByteOrder_16(ByteSwapped[I]);
Src = &ByteSwapped[0];
SrcEnd = &ByteSwapped[ByteSwapped.size() - 1] + 1;
}
// Skip the BOM for conversion.
if (Src[0] == UNI_UTF16_BYTE_ORDER_MARK_NATIVE)
Src++;
// Just allocate enough space up front. We'll shrink it later.
Out.resize(SrcBytes.size() * UNI_MAX_UTF8_BYTES_PER_CODE_POINT);
UTF8 *Dst = reinterpret_cast<UTF8 *>(&Out[0]);
UTF8 *DstEnd = Dst + Out.size();
ConversionResult CR =
ConvertUTF16toUTF8(&Src, SrcEnd, &Dst, DstEnd, strictConversion);
assert(CR != targetExhausted);
if (CR != conversionOK) {
Out.clear();
return false;
}
Out.resize(reinterpret_cast<char *>(Dst) - &Out[0]);
return true;
}
} // end namespace llvm