1 //===- CXString.cpp - Routines for manipulating CXStrings -----------------===// 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 // This file defines routines for manipulating CXStrings. It should be the 11 // only file that has internal knowledge of the encoding of the data in 12 // CXStrings. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "CXString.h" 17 #include "CXTranslationUnit.h" 18 #include "clang-c/Index.h" 19 #include "clang/Frontend/ASTUnit.h" 20 #include "llvm/ADT/SmallString.h" 21 #include "llvm/Support/ErrorHandling.h" 22 23 using namespace clang; 24 25 /// Describes the kind of underlying data in CXString. 26 enum CXStringFlag { 27 /// CXString contains a 'const char *' that it doesn't own. 28 CXS_Unmanaged, 29 30 /// CXString contains a 'const char *' that it allocated with malloc(). 31 CXS_Malloc, 32 33 /// CXString contains a CXStringBuf that needs to be returned to the 34 /// CXStringPool. 35 CXS_StringBuf 36 }; 37 38 namespace clang { 39 namespace cxstring { 40 41 //===----------------------------------------------------------------------===// 42 // Basic generation of CXStrings. 43 //===----------------------------------------------------------------------===// 44 createEmpty()45 CXString createEmpty() { 46 CXString Str; 47 Str.data = ""; 48 Str.private_flags = CXS_Unmanaged; 49 return Str; 50 } 51 createNull()52 CXString createNull() { 53 CXString Str; 54 Str.data = nullptr; 55 Str.private_flags = CXS_Unmanaged; 56 return Str; 57 } 58 createRef(const char * String)59 CXString createRef(const char *String) { 60 if (String && String[0] == '\0') 61 return createEmpty(); 62 63 CXString Str; 64 Str.data = String; 65 Str.private_flags = CXS_Unmanaged; 66 return Str; 67 } 68 createDup(const char * String)69 CXString createDup(const char *String) { 70 if (!String) 71 return createNull(); 72 73 if (String[0] == '\0') 74 return createEmpty(); 75 76 CXString Str; 77 Str.data = strdup(String); 78 Str.private_flags = CXS_Malloc; 79 return Str; 80 } 81 createRef(StringRef String)82 CXString createRef(StringRef String) { 83 // If the string is not nul-terminated, we have to make a copy. 84 85 // FIXME: This is doing a one past end read, and should be removed! For memory 86 // we don't manage, the API string can become unterminated at any time outside 87 // our control. 88 89 if (!String.empty() && String.data()[String.size()] != 0) 90 return createDup(String); 91 92 CXString Result; 93 Result.data = String.data(); 94 Result.private_flags = (unsigned) CXS_Unmanaged; 95 return Result; 96 } 97 createDup(StringRef String)98 CXString createDup(StringRef String) { 99 CXString Result; 100 char *Spelling = static_cast<char *>(malloc(String.size() + 1)); 101 memmove(Spelling, String.data(), String.size()); 102 Spelling[String.size()] = 0; 103 Result.data = Spelling; 104 Result.private_flags = (unsigned) CXS_Malloc; 105 return Result; 106 } 107 createCXString(CXStringBuf * buf)108 CXString createCXString(CXStringBuf *buf) { 109 CXString Str; 110 Str.data = buf; 111 Str.private_flags = (unsigned) CXS_StringBuf; 112 return Str; 113 } 114 115 116 //===----------------------------------------------------------------------===// 117 // String pools. 118 //===----------------------------------------------------------------------===// 119 ~CXStringPool()120 CXStringPool::~CXStringPool() { 121 for (std::vector<CXStringBuf *>::iterator I = Pool.begin(), E = Pool.end(); 122 I != E; ++I) { 123 delete *I; 124 } 125 } 126 getCXStringBuf(CXTranslationUnit TU)127 CXStringBuf *CXStringPool::getCXStringBuf(CXTranslationUnit TU) { 128 if (Pool.empty()) 129 return new CXStringBuf(TU); 130 131 CXStringBuf *Buf = Pool.back(); 132 Buf->Data.clear(); 133 Pool.pop_back(); 134 return Buf; 135 } 136 getCXStringBuf(CXTranslationUnit TU)137 CXStringBuf *getCXStringBuf(CXTranslationUnit TU) { 138 return TU->StringPool->getCXStringBuf(TU); 139 } 140 dispose()141 void CXStringBuf::dispose() { 142 TU->StringPool->Pool.push_back(this); 143 } 144 isManagedByPool(CXString str)145 bool isManagedByPool(CXString str) { 146 return ((CXStringFlag) str.private_flags) == CXS_StringBuf; 147 } 148 149 } // end namespace cxstring 150 } // end namespace clang 151 152 //===----------------------------------------------------------------------===// 153 // libClang public APIs. 154 //===----------------------------------------------------------------------===// 155 156 extern "C" { clang_getCString(CXString string)157 const char *clang_getCString(CXString string) { 158 if (string.private_flags == (unsigned) CXS_StringBuf) { 159 return static_cast<const cxstring::CXStringBuf *>(string.data)->Data.data(); 160 } 161 return static_cast<const char *>(string.data); 162 } 163 clang_disposeString(CXString string)164 void clang_disposeString(CXString string) { 165 switch ((CXStringFlag) string.private_flags) { 166 case CXS_Unmanaged: 167 break; 168 case CXS_Malloc: 169 if (string.data) 170 free(const_cast<void *>(string.data)); 171 break; 172 case CXS_StringBuf: 173 static_cast<cxstring::CXStringBuf *>( 174 const_cast<void *>(string.data))->dispose(); 175 break; 176 } 177 } 178 } // end: extern "C" 179 180