1 //===-- Status.cpp -----------------------------------------------*- C++ 2 //-*-===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "lldb/Utility/Status.h" 11 12 #include "lldb/Utility/VASPrintf.h" 13 #include "lldb/lldb-defines.h" 14 #include "lldb/lldb-enumerations.h" 15 #include "llvm/ADT/SmallString.h" 16 #include "llvm/ADT/StringRef.h" 17 #include "llvm/Support/Errno.h" 18 #include "llvm/Support/FormatProviders.h" 19 20 #include <cerrno> 21 #include <cstdarg> 22 #include <string> 23 #include <system_error> 24 25 #ifdef __APPLE__ 26 #include <mach/mach.h> 27 #endif 28 29 #ifdef _WIN32 30 #include <windows.h> 31 #endif 32 #include <stdint.h> 33 34 namespace llvm { 35 class raw_ostream; 36 } 37 38 using namespace lldb; 39 using namespace lldb_private; 40 41 Status::Status() : m_code(0), m_type(eErrorTypeInvalid), m_string() {} 42 43 Status::Status(ValueType err, ErrorType type) 44 : m_code(err), m_type(type), m_string() {} 45 46 Status::Status(std::error_code EC) 47 : m_code(EC.value()), m_type(ErrorType::eErrorTypeGeneric), 48 m_string(EC.message()) {} 49 50 Status::Status(const char *format, ...) 51 : m_code(0), m_type(eErrorTypeInvalid), m_string() { 52 va_list args; 53 va_start(args, format); 54 SetErrorToGenericError(); 55 SetErrorStringWithVarArg(format, args); 56 va_end(args); 57 } 58 59 const Status &Status::operator=(llvm::Error error) { 60 if (!error) { 61 Clear(); 62 return *this; 63 } 64 65 // if the error happens to be a errno error, preserve the error code 66 error = llvm::handleErrors( 67 std::move(error), [&](std::unique_ptr<llvm::ECError> e) -> llvm::Error { 68 std::error_code ec = e->convertToErrorCode(); 69 if (ec.category() == std::generic_category()) { 70 m_code = ec.value(); 71 m_type = ErrorType::eErrorTypePOSIX; 72 return llvm::Error::success(); 73 } 74 return llvm::Error(std::move(e)); 75 }); 76 77 // Otherwise, just preserve the message 78 if (error) { 79 SetErrorToGenericError(); 80 SetErrorString(llvm::toString(std::move(error))); 81 } 82 83 return *this; 84 } 85 86 llvm::Error Status::ToError() const { 87 if (Success()) 88 return llvm::Error::success(); 89 if (m_type == ErrorType::eErrorTypePOSIX) 90 return llvm::errorCodeToError( 91 std::error_code(m_code, std::generic_category())); 92 return llvm::make_error<llvm::StringError>(AsCString(), 93 llvm::inconvertibleErrorCode()); 94 } 95 96 Status::~Status() = default; 97 98 #ifdef _WIN32 99 static std::string RetrieveWin32ErrorString(uint32_t error_code) { 100 char *buffer = nullptr; 101 std::string message; 102 // Retrieve win32 system error. 103 // First, attempt to load a en-US message 104 if (::FormatMessageA( 105 FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | 106 FORMAT_MESSAGE_MAX_WIDTH_MASK, 107 NULL, error_code, MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US), 108 (LPSTR)&buffer, 0, NULL)) { 109 message.assign(buffer); 110 ::LocalFree(buffer); 111 } 112 // If the previous didn't work, use the default OS language 113 else if (::FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | 114 FORMAT_MESSAGE_FROM_SYSTEM | 115 FORMAT_MESSAGE_MAX_WIDTH_MASK, 116 NULL, error_code, 0, (LPSTR)&buffer, 0, NULL)) { 117 message.assign(buffer); 118 ::LocalFree(buffer); 119 } 120 return message; 121 } 122 #endif 123 124 // Get the error value as a NULL C string. The error string will be fetched and 125 // cached on demand. The cached error string value will remain until the error 126 // value is changed or cleared. 127 const char *Status::AsCString(const char *default_error_str) const { 128 if (Success()) 129 return nullptr; 130 131 if (m_string.empty()) { 132 switch (m_type) { 133 case eErrorTypeMachKernel: 134 #if defined(__APPLE__) 135 if (const char *s = ::mach_error_string(m_code)) 136 m_string.assign(s); 137 #endif 138 break; 139 140 case eErrorTypePOSIX: 141 m_string = llvm::sys::StrError(m_code); 142 break; 143 144 case eErrorTypeWin32: 145 #if defined(_WIN32) 146 m_string = RetrieveWin32ErrorString(m_code); 147 #endif 148 break; 149 150 default: 151 break; 152 } 153 } 154 if (m_string.empty()) { 155 if (default_error_str) 156 m_string.assign(default_error_str); 157 else 158 return nullptr; // User wanted a nullptr string back... 159 } 160 return m_string.c_str(); 161 } 162 163 // Clear the error and any cached error string that it might contain. 164 void Status::Clear() { 165 m_code = 0; 166 m_type = eErrorTypeInvalid; 167 m_string.clear(); 168 } 169 170 // Access the error value. 171 Status::ValueType Status::GetError() const { return m_code; } 172 173 // Access the error type. 174 ErrorType Status::GetType() const { return m_type; } 175 176 // Returns true if this object contains a value that describes an error or 177 // otherwise non-success result. 178 bool Status::Fail() const { return m_code != 0; } 179 180 // Set accessor for the error value to "err" and the type to 181 // "eErrorTypeMachKernel" 182 void Status::SetMachError(uint32_t err) { 183 m_code = err; 184 m_type = eErrorTypeMachKernel; 185 m_string.clear(); 186 } 187 188 void Status::SetExpressionError(lldb::ExpressionResults result, 189 const char *mssg) { 190 m_code = result; 191 m_type = eErrorTypeExpression; 192 m_string = mssg; 193 } 194 195 int Status::SetExpressionErrorWithFormat(lldb::ExpressionResults result, 196 const char *format, ...) { 197 int length = 0; 198 199 if (format != nullptr && format[0]) { 200 va_list args; 201 va_start(args, format); 202 length = SetErrorStringWithVarArg(format, args); 203 va_end(args); 204 } else { 205 m_string.clear(); 206 } 207 m_code = result; 208 m_type = eErrorTypeExpression; 209 return length; 210 } 211 212 // Set accessor for the error value and type. 213 void Status::SetError(ValueType err, ErrorType type) { 214 m_code = err; 215 m_type = type; 216 m_string.clear(); 217 } 218 219 // Update the error value to be "errno" and update the type to be "POSIX". 220 void Status::SetErrorToErrno() { 221 m_code = errno; 222 m_type = eErrorTypePOSIX; 223 m_string.clear(); 224 } 225 226 // Update the error value to be LLDB_GENERIC_ERROR and update the type to be 227 // "Generic". 228 void Status::SetErrorToGenericError() { 229 m_code = LLDB_GENERIC_ERROR; 230 m_type = eErrorTypeGeneric; 231 m_string.clear(); 232 } 233 234 // Set accessor for the error string value for a specific error. This allows 235 // any string to be supplied as an error explanation. The error string value 236 // will remain until the error value is cleared or a new error value/type is 237 // assigned. 238 void Status::SetErrorString(llvm::StringRef err_str) { 239 if (!err_str.empty()) { 240 // If we have an error string, we should always at least have an error set 241 // to a generic value. 242 if (Success()) 243 SetErrorToGenericError(); 244 } 245 m_string = err_str; 246 } 247 248 /// Set the current error string to a formatted error string. 249 /// 250 /// \param format 251 /// A printf style format string 252 int Status::SetErrorStringWithFormat(const char *format, ...) { 253 if (format != nullptr && format[0]) { 254 va_list args; 255 va_start(args, format); 256 int length = SetErrorStringWithVarArg(format, args); 257 va_end(args); 258 return length; 259 } else { 260 m_string.clear(); 261 } 262 return 0; 263 } 264 265 int Status::SetErrorStringWithVarArg(const char *format, va_list args) { 266 if (format != nullptr && format[0]) { 267 // If we have an error string, we should always at least have an error set 268 // to a generic value. 269 if (Success()) 270 SetErrorToGenericError(); 271 272 llvm::SmallString<1024> buf; 273 VASprintf(buf, format, args); 274 m_string = buf.str(); 275 return buf.size(); 276 } else { 277 m_string.clear(); 278 } 279 return 0; 280 } 281 282 // Returns true if the error code in this object is considered a successful 283 // return value. 284 bool Status::Success() const { return m_code == 0; } 285 286 bool Status::WasInterrupted() const { 287 return (m_type == eErrorTypePOSIX && m_code == EINTR); 288 } 289 290 void llvm::format_provider<lldb_private::Status>::format( 291 const lldb_private::Status &error, llvm::raw_ostream &OS, 292 llvm::StringRef Options) { 293 llvm::format_provider<llvm::StringRef>::format(error.AsCString(), OS, 294 Options); 295 } 296