1//===-- ConvertUTFWrapper.cpp - Wrap ConvertUTF.h with clang data types -----===
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "llvm/Support/ConvertUTF.h"
11#include "llvm/Support/SwapByteOrder.h"
12#include <string>
13#include <vector>
14
15namespace llvm {
16
17bool ConvertUTF8toWide(unsigned WideCharWidth, llvm::StringRef Source,
18                       char *&ResultPtr, const UTF8 *&ErrorPtr) {
19  assert(WideCharWidth == 1 || WideCharWidth == 2 || WideCharWidth == 4);
20  ConversionResult result = conversionOK;
21  // Copy the character span over.
22  if (WideCharWidth == 1) {
23    const UTF8 *Pos = reinterpret_cast<const UTF8*>(Source.begin());
24    if (!isLegalUTF8String(&Pos, reinterpret_cast<const UTF8*>(Source.end()))) {
25      result = sourceIllegal;
26      ErrorPtr = Pos;
27    } else {
28      memcpy(ResultPtr, Source.data(), Source.size());
29      ResultPtr += Source.size();
30    }
31  } else if (WideCharWidth == 2) {
32    const UTF8 *sourceStart = (const UTF8*)Source.data();
33    // FIXME: Make the type of the result buffer correct instead of
34    // using reinterpret_cast.
35    UTF16 *targetStart = reinterpret_cast<UTF16*>(ResultPtr);
36    ConversionFlags flags = strictConversion;
37    result = ConvertUTF8toUTF16(
38        &sourceStart, sourceStart + Source.size(),
39        &targetStart, targetStart + 2*Source.size(), flags);
40    if (result == conversionOK)
41      ResultPtr = reinterpret_cast<char*>(targetStart);
42    else
43      ErrorPtr = sourceStart;
44  } else if (WideCharWidth == 4) {
45    const UTF8 *sourceStart = (const UTF8*)Source.data();
46    // FIXME: Make the type of the result buffer correct instead of
47    // using reinterpret_cast.
48    UTF32 *targetStart = reinterpret_cast<UTF32*>(ResultPtr);
49    ConversionFlags flags = strictConversion;
50    result = ConvertUTF8toUTF32(
51        &sourceStart, sourceStart + Source.size(),
52        &targetStart, targetStart + 4*Source.size(), flags);
53    if (result == conversionOK)
54      ResultPtr = reinterpret_cast<char*>(targetStart);
55    else
56      ErrorPtr = sourceStart;
57  }
58  assert((result != targetExhausted)
59         && "ConvertUTF8toUTFXX exhausted target buffer");
60  return result == conversionOK;
61}
62
63bool ConvertCodePointToUTF8(unsigned Source, char *&ResultPtr) {
64  const UTF32 *SourceStart = &Source;
65  const UTF32 *SourceEnd = SourceStart + 1;
66  UTF8 *TargetStart = reinterpret_cast<UTF8 *>(ResultPtr);
67  UTF8 *TargetEnd = TargetStart + 4;
68  ConversionResult CR = ConvertUTF32toUTF8(&SourceStart, SourceEnd,
69                                           &TargetStart, TargetEnd,
70                                           strictConversion);
71  if (CR != conversionOK)
72    return false;
73
74  ResultPtr = reinterpret_cast<char*>(TargetStart);
75  return true;
76}
77
78bool hasUTF16ByteOrderMark(ArrayRef<char> S) {
79  return (S.size() >= 2 &&
80          ((S[0] == '\xff' && S[1] == '\xfe') ||
81           (S[0] == '\xfe' && S[1] == '\xff')));
82}
83
84bool convertUTF16ToUTF8String(ArrayRef<char> SrcBytes, std::string &Out) {
85  assert(Out.empty());
86
87  // Error out on an uneven byte count.
88  if (SrcBytes.size() % 2)
89    return false;
90
91  // Avoid OOB by returning early on empty input.
92  if (SrcBytes.empty())
93    return true;
94
95  const UTF16 *Src = reinterpret_cast<const UTF16 *>(SrcBytes.begin());
96  const UTF16 *SrcEnd = reinterpret_cast<const UTF16 *>(SrcBytes.end());
97
98  // Byteswap if necessary.
99  std::vector<UTF16> ByteSwapped;
100  if (Src[0] == UNI_UTF16_BYTE_ORDER_MARK_SWAPPED) {
101    ByteSwapped.insert(ByteSwapped.end(), Src, SrcEnd);
102    for (unsigned I = 0, E = ByteSwapped.size(); I != E; ++I)
103      ByteSwapped[I] = llvm::sys::SwapByteOrder_16(ByteSwapped[I]);
104    Src = &ByteSwapped[0];
105    SrcEnd = &ByteSwapped[ByteSwapped.size() - 1] + 1;
106  }
107
108  // Skip the BOM for conversion.
109  if (Src[0] == UNI_UTF16_BYTE_ORDER_MARK_NATIVE)
110    Src++;
111
112  // Just allocate enough space up front.  We'll shrink it later.  Allocate
113  // enough that we can fit a null terminator without reallocating.
114  Out.resize(SrcBytes.size() * UNI_MAX_UTF8_BYTES_PER_CODE_POINT + 1);
115  UTF8 *Dst = reinterpret_cast<UTF8 *>(&Out[0]);
116  UTF8 *DstEnd = Dst + Out.size();
117
118  ConversionResult CR =
119      ConvertUTF16toUTF8(&Src, SrcEnd, &Dst, DstEnd, strictConversion);
120  assert(CR != targetExhausted);
121
122  if (CR != conversionOK) {
123    Out.clear();
124    return false;
125  }
126
127  Out.resize(reinterpret_cast<char *>(Dst) - &Out[0]);
128  Out.push_back(0);
129  Out.pop_back();
130  return true;
131}
132
133bool convertUTF8ToUTF16String(StringRef SrcUTF8,
134                              SmallVectorImpl<UTF16> &DstUTF16) {
135  assert(DstUTF16.empty());
136
137  // Avoid OOB by returning early on empty input.
138  if (SrcUTF8.empty()) {
139    DstUTF16.push_back(0);
140    DstUTF16.pop_back();
141    return true;
142  }
143
144  const UTF8 *Src = reinterpret_cast<const UTF8 *>(SrcUTF8.begin());
145  const UTF8 *SrcEnd = reinterpret_cast<const UTF8 *>(SrcUTF8.end());
146
147  // Allocate the same number of UTF-16 code units as UTF-8 code units. Encoding
148  // as UTF-16 should always require the same amount or less code units than the
149  // UTF-8 encoding.  Allocate one extra byte for the null terminator though,
150  // so that someone calling DstUTF16.data() gets a null terminated string.
151  // We resize down later so we don't have to worry that this over allocates.
152  DstUTF16.resize(SrcUTF8.size()+1);
153  UTF16 *Dst = &DstUTF16[0];
154  UTF16 *DstEnd = Dst + DstUTF16.size();
155
156  ConversionResult CR =
157      ConvertUTF8toUTF16(&Src, SrcEnd, &Dst, DstEnd, strictConversion);
158  assert(CR != targetExhausted);
159
160  if (CR != conversionOK) {
161    DstUTF16.clear();
162    return false;
163  }
164
165  DstUTF16.resize(Dst - &DstUTF16[0]);
166  DstUTF16.push_back(0);
167  DstUTF16.pop_back();
168  return true;
169}
170
171} // end namespace llvm
172
173