llvm-project/lldb/source/Utility/Status.cpp

295 lines
8.1 KiB
C++

//===-- Status.cpp --------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "lldb/Utility/Status.h"
#include "lldb/Utility/VASPrintf.h"
#include "lldb/lldb-defines.h"
#include "lldb/lldb-enumerations.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Errno.h"
#include "llvm/Support/FormatProviders.h"
#include <cerrno>
#include <cstdarg>
#include <string>
#include <system_error>
#ifdef __APPLE__
#include <mach/mach.h>
#endif
#ifdef _WIN32
#include <windows.h>
#endif
#include <stdint.h>
namespace llvm {
class raw_ostream;
}
using namespace lldb;
using namespace lldb_private;
Status::Status() : m_code(0), m_type(eErrorTypeInvalid), m_string() {}
Status::Status(ValueType err, ErrorType type)
: m_code(err), m_type(type), m_string() {}
Status::Status(std::error_code EC)
: m_code(EC.value()), m_type(ErrorType::eErrorTypeGeneric),
m_string(EC.message()) {}
Status::Status(const char *format, ...)
: m_code(0), m_type(eErrorTypeInvalid), m_string() {
va_list args;
va_start(args, format);
SetErrorToGenericError();
SetErrorStringWithVarArg(format, args);
va_end(args);
}
const Status &Status::operator=(llvm::Error error) {
if (!error) {
Clear();
return *this;
}
// if the error happens to be a errno error, preserve the error code
error = llvm::handleErrors(
std::move(error), [&](std::unique_ptr<llvm::ECError> e) -> llvm::Error {
std::error_code ec = e->convertToErrorCode();
if (ec.category() == std::generic_category()) {
m_code = ec.value();
m_type = ErrorType::eErrorTypePOSIX;
return llvm::Error::success();
}
return llvm::Error(std::move(e));
});
// Otherwise, just preserve the message
if (error) {
SetErrorToGenericError();
SetErrorString(llvm::toString(std::move(error)));
}
return *this;
}
llvm::Error Status::ToError() const {
if (Success())
return llvm::Error::success();
if (m_type == ErrorType::eErrorTypePOSIX)
return llvm::errorCodeToError(
std::error_code(m_code, std::generic_category()));
return llvm::make_error<llvm::StringError>(AsCString(),
llvm::inconvertibleErrorCode());
}
Status::~Status() = default;
#ifdef _WIN32
static std::string RetrieveWin32ErrorString(uint32_t error_code) {
char *buffer = nullptr;
std::string message;
// Retrieve win32 system error.
// First, attempt to load a en-US message
if (::FormatMessageA(
FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_MAX_WIDTH_MASK,
NULL, error_code, MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US),
(LPSTR)&buffer, 0, NULL)) {
message.assign(buffer);
::LocalFree(buffer);
}
// If the previous didn't work, use the default OS language
else if (::FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_MAX_WIDTH_MASK,
NULL, error_code, 0, (LPSTR)&buffer, 0, NULL)) {
message.assign(buffer);
::LocalFree(buffer);
}
return message;
}
#endif
// Get the error value as a NULL C string. The error string will be fetched and
// cached on demand. The cached error string value will remain until the error
// value is changed or cleared.
const char *Status::AsCString(const char *default_error_str) const {
if (Success())
return nullptr;
if (m_string.empty()) {
switch (m_type) {
case eErrorTypeMachKernel:
#if defined(__APPLE__)
if (const char *s = ::mach_error_string(m_code))
m_string.assign(s);
#endif
break;
case eErrorTypePOSIX:
m_string = llvm::sys::StrError(m_code);
break;
case eErrorTypeWin32:
#if defined(_WIN32)
m_string = RetrieveWin32ErrorString(m_code);
#endif
break;
default:
break;
}
}
if (m_string.empty()) {
if (default_error_str)
m_string.assign(default_error_str);
else
return nullptr; // User wanted a nullptr string back...
}
return m_string.c_str();
}
// Clear the error and any cached error string that it might contain.
void Status::Clear() {
m_code = 0;
m_type = eErrorTypeInvalid;
m_string.clear();
}
// Access the error value.
Status::ValueType Status::GetError() const { return m_code; }
// Access the error type.
ErrorType Status::GetType() const { return m_type; }
// Returns true if this object contains a value that describes an error or
// otherwise non-success result.
bool Status::Fail() const { return m_code != 0; }
// Set accessor for the error value to "err" and the type to
// "eErrorTypeMachKernel"
void Status::SetMachError(uint32_t err) {
m_code = err;
m_type = eErrorTypeMachKernel;
m_string.clear();
}
void Status::SetExpressionError(lldb::ExpressionResults result,
const char *mssg) {
m_code = result;
m_type = eErrorTypeExpression;
m_string = mssg;
}
int Status::SetExpressionErrorWithFormat(lldb::ExpressionResults result,
const char *format, ...) {
int length = 0;
if (format != nullptr && format[0]) {
va_list args;
va_start(args, format);
length = SetErrorStringWithVarArg(format, args);
va_end(args);
} else {
m_string.clear();
}
m_code = result;
m_type = eErrorTypeExpression;
return length;
}
// Set accessor for the error value and type.
void Status::SetError(ValueType err, ErrorType type) {
m_code = err;
m_type = type;
m_string.clear();
}
// Update the error value to be "errno" and update the type to be "POSIX".
void Status::SetErrorToErrno() {
m_code = errno;
m_type = eErrorTypePOSIX;
m_string.clear();
}
// Update the error value to be LLDB_GENERIC_ERROR and update the type to be
// "Generic".
void Status::SetErrorToGenericError() {
m_code = LLDB_GENERIC_ERROR;
m_type = eErrorTypeGeneric;
m_string.clear();
}
// Set accessor for the error string value for a specific error. This allows
// any string to be supplied as an error explanation. The error string value
// will remain until the error value is cleared or a new error value/type is
// assigned.
void Status::SetErrorString(llvm::StringRef err_str) {
if (!err_str.empty()) {
// If we have an error string, we should always at least have an error set
// to a generic value.
if (Success())
SetErrorToGenericError();
}
m_string = std::string(err_str);
}
/// Set the current error string to a formatted error string.
///
/// \param format
/// A printf style format string
int Status::SetErrorStringWithFormat(const char *format, ...) {
if (format != nullptr && format[0]) {
va_list args;
va_start(args, format);
int length = SetErrorStringWithVarArg(format, args);
va_end(args);
return length;
} else {
m_string.clear();
}
return 0;
}
int Status::SetErrorStringWithVarArg(const char *format, va_list args) {
if (format != nullptr && format[0]) {
// If we have an error string, we should always at least have an error set
// to a generic value.
if (Success())
SetErrorToGenericError();
llvm::SmallString<1024> buf;
VASprintf(buf, format, args);
m_string = std::string(buf.str());
return buf.size();
} else {
m_string.clear();
}
return 0;
}
// Returns true if the error code in this object is considered a successful
// return value.
bool Status::Success() const { return m_code == 0; }
bool Status::WasInterrupted() const {
return (m_type == eErrorTypePOSIX && m_code == EINTR);
}
void llvm::format_provider<lldb_private::Status>::format(
const lldb_private::Status &error, llvm::raw_ostream &OS,
llvm::StringRef Options) {
llvm::format_provider<llvm::StringRef>::format(error.AsCString(), OS,
Options);
}