Modernize raw_fd_ostream's constructor a bit.

Take a StringRef instead of a "const char *".
Take a "std::error_code &" instead of a "std::string &" for error.

A create static method would be even better, but this patch is already a bit too
big.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216393 91177308-0d34-0410-b5e6-96231b3b80d8

examples/BrainF/BrainFDriver.cpp

@@ -107,9 +107,8 @@ int main(int argc, char **argv) {
       OutputFilename = base+".bc";
     }
     if (OutputFilename != "-") {
-      std::string ErrInfo;
-      out = new raw_fd_ostream(OutputFilename.c_str(), ErrInfo,
-                               sys::fs::F_None);
+      std::error_code EC;
+      out = new raw_fd_ostream(OutputFilename, EC, sys::fs::F_None);
     }
   }
 

include/llvm/Analysis/DOTGraphTraitsPass.h

@@ -66,15 +66,15 @@ class DOTGraphTraitsPrinter : public FunctionPass {
   bool runOnFunction(Function &F) override {
     GraphT Graph = AnalysisGraphTraitsT::getGraph(&getAnalysis<AnalysisT>());
     std::string Filename = Name + "." + F.getName().str() + ".dot";
-    std::string ErrorInfo;
+    std::error_code EC;
 
     errs() << "Writing '" << Filename << "'...";
 
-    raw_fd_ostream File(Filename.c_str(), ErrorInfo, sys::fs::F_Text);
+    raw_fd_ostream File(Filename, EC, sys::fs::F_Text);
     std::string GraphName = DOTGraphTraits<GraphT>::getGraphName(Graph);
     std::string Title = GraphName + " for '" + F.getName().str() + "' function";
 
-    if (ErrorInfo.empty())
+    if (!EC)
       WriteGraph(File, Graph, IsSimple, Title);
     else
       errs() << "  error opening file for writing!";
@@ -129,14 +129,14 @@ class DOTGraphTraitsModulePrinter : public ModulePass {
   bool runOnModule(Module &M) override {
     GraphT Graph = AnalysisGraphTraitsT::getGraph(&getAnalysis<AnalysisT>());
     std::string Filename = Name + ".dot";
-    std::string ErrorInfo;
+    std::error_code EC;
 
     errs() << "Writing '" << Filename << "'...";
 
-    raw_fd_ostream File(Filename.c_str(), ErrorInfo, sys::fs::F_Text);
+    raw_fd_ostream File(Filename, EC, sys::fs::F_Text);
     std::string Title = DOTGraphTraits<GraphT>::getGraphName(Graph);
 
-    if (ErrorInfo.empty())
+    if (!EC)
       WriteGraph(File, Graph, IsSimple, Title);
     else
       errs() << "  error opening file for writing!";

include/llvm/Support/ToolOutputFile.h

@@ -29,13 +29,13 @@ class tool_output_file {
   /// destructed after the raw_fd_ostream is destructed. It installs
   /// cleanups in its constructor and uninstalls them in its destructor.
   class CleanupInstaller {
-    /// Filename - The name of the file.
+    /// The name of the file.
     std::string Filename;
   public:
-    /// Keep - The flag which indicates whether we should not delete the file.
+    /// The flag which indicates whether we should not delete the file.
     bool Keep;
 
-    explicit CleanupInstaller(const char *filename);
+    explicit CleanupInstaller(StringRef ilename);
     ~CleanupInstaller();
   } Installer;
 
@@ -44,12 +44,12 @@ class tool_output_file {
   raw_fd_ostream OS;
 
 public:
-  /// tool_output_file - This constructor's arguments are passed to
-  /// to raw_fd_ostream's constructor.
-  tool_output_file(const char *filename, std::string &ErrorInfo,
+  /// This constructor's arguments are passed to to raw_fd_ostream's
+  /// constructor.
+  tool_output_file(StringRef Filename, std::error_code &EC,
                    sys::fs::OpenFlags Flags);
 
-  tool_output_file(const char *Filename, int FD);
+  tool_output_file(StringRef Filename, int FD);
 
   /// os - Return the contained raw_fd_ostream.
   raw_fd_ostream &os() { return OS; }

include/llvm/Support/raw_ostream.h

@@ -17,6 +17,7 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/DataTypes.h"
+#include <system_error>
 
 namespace llvm {
   class format_object_base;
@@ -341,17 +342,17 @@ class raw_fd_ostream : public raw_ostream {
   void error_detected() { Error = true; }
 
 public:
-  /// raw_fd_ostream - Open the specified file for writing. If an error occurs,
-  /// information about the error is put into ErrorInfo, and the stream should
-  /// be immediately destroyed; the string will be empty if no error occurred.
-  /// This allows optional flags to control how the file will be opened.
+  /// Open the specified file for writing. If an error occurs, information
+  /// about the error is put into EC, and the stream should be immediately
+  /// destroyed;
+  /// \p Flags allows optional flags to control how the file will be opened.
   ///
   /// As a special case, if Filename is "-", then the stream will use
   /// STDOUT_FILENO instead of opening a file. Note that it will still consider
   /// itself to own the file descriptor. In particular, it will close the
   /// file descriptor when it is done (this is necessary to detect
   /// output errors).
-  raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
+  raw_fd_ostream(StringRef Filename, std::error_code &EC,
                  sys::fs::OpenFlags Flags);
 
   /// raw_fd_ostream ctor - FD is the file descriptor that this writes to.  If

lib/Analysis/CFGPrinter.cpp

@@ -79,11 +79,11 @@ namespace {
     bool runOnFunction(Function &F) override {
       std::string Filename = "cfg." + F.getName().str() + ".dot";
       errs() << "Writing '" << Filename << "'...";
-
-      std::string ErrorInfo;
-      raw_fd_ostream File(Filename.c_str(), ErrorInfo, sys::fs::F_Text);
 
-      if (ErrorInfo.empty())
+      std::error_code EC;
+      raw_fd_ostream File(Filename, EC, sys::fs::F_Text);
+
+      if (!EC)
         WriteGraph(File, (const Function*)&F);
       else
         errs() << "  error opening file for writing!";
@@ -114,10 +114,10 @@ namespace {
       std::string Filename = "cfg." + F.getName().str() + ".dot";
       errs() << "Writing '" << Filename << "'...";
 
-      std::string ErrorInfo;
-      raw_fd_ostream File(Filename.c_str(), ErrorInfo, sys::fs::F_Text);
-      
-      if (ErrorInfo.empty())
+      std::error_code EC;
+      raw_fd_ostream File(Filename, EC, sys::fs::F_Text);
+
+      if (!EC)
         WriteGraph(File, (const Function*)&F, true);
       else
         errs() << "  error opening file for writing!";

lib/Bitcode/Writer/BitWriter.cpp

@@ -18,10 +18,10 @@ using namespace llvm;
 /*===-- Operations on modules ---------------------------------------------===*/
 
 int LLVMWriteBitcodeToFile(LLVMModuleRef M, const char *Path) {
-  std::string ErrorInfo;
-  raw_fd_ostream OS(Path, ErrorInfo, sys::fs::F_None);
+  std::error_code EC;
+  raw_fd_ostream OS(Path, EC, sys::fs::F_None);
 
-  if (!ErrorInfo.empty())
+  if (EC)
     return -1;
 
   WriteBitcodeToFile(unwrap(M), OS);

lib/CodeGen/MachineVerifier.cpp

@@ -276,11 +276,12 @@ void MachineFunction::verify(Pass *p, const char *Banner) const {
 bool MachineVerifier::runOnMachineFunction(MachineFunction &MF) {
   raw_ostream *OutFile = nullptr;
   if (OutFileName) {
-    std::string ErrorInfo;
-    OutFile = new raw_fd_ostream(OutFileName, ErrorInfo,
+    std::error_code EC;
+    OutFile = new raw_fd_ostream(OutFileName, EC,
                                  sys::fs::F_Append | sys::fs::F_Text);
-    if (!ErrorInfo.empty()) {
-      errs() << "Error opening '" << OutFileName << "': " << ErrorInfo << '\n';
+    if (EC) {
+      errs() << "Error opening '" << OutFileName << "': " << EC.message()
+             << '\n';
       exit(1);
     }
 

lib/CodeGen/RegAllocPBQP.cpp

@@ -587,8 +587,8 @@ bool RegAllocPBQP::runOnMachineFunction(MachineFunction &MF) {
         std::ostringstream rs;
         rs << round;
         std::string graphFileName(fqn + "." + rs.str() + ".pbqpgraph");
-        std::string tmp;
-        raw_fd_ostream os(graphFileName.c_str(), tmp, sys::fs::F_Text);
+        std::error_code EC;
+        raw_fd_ostream os(graphFileName, EC, sys::fs::F_Text);
         DEBUG(dbgs() << "Dumping graph for round " << round << " to \""
               << graphFileName << "\"\n");
         problem->getGraph().dump(os);

lib/IR/Core.cpp

@@ -183,20 +183,22 @@ void LLVMDumpModule(LLVMModuleRef M) {
 
 LLVMBool LLVMPrintModuleToFile(LLVMModuleRef M, const char *Filename,
                                char **ErrorMessage) {
-  std::string error;
-  raw_fd_ostream dest(Filename, error, sys::fs::F_Text);
-  if (!error.empty()) {
-    *ErrorMessage = strdup(error.c_str());
+  std::error_code EC;
+  raw_fd_ostream dest(Filename, EC, sys::fs::F_Text);
+  if (EC) {
+    *ErrorMessage = strdup(EC.message().c_str());
     return true;
   }
 
   unwrap(M)->print(dest, nullptr);
 
-  if (!error.empty()) {
-    *ErrorMessage = strdup(error.c_str());
+  dest.close();
+
+  if (dest.has_error()) {
+    *ErrorMessage = strdup("Error printing to file");
     return true;
   }
-  dest.flush();
+
   return false;
 }
 

lib/IR/GCOV.cpp

@@ -517,11 +517,11 @@ FileInfo::openCoveragePath(StringRef CoveragePath) {
   if (Options.NoOutput)
     return llvm::make_unique<raw_null_ostream>();
 
-  std::string ErrorInfo;
-  auto OS = llvm::make_unique<raw_fd_ostream>(CoveragePath.str().c_str(),
-                                              ErrorInfo, sys::fs::F_Text);
-  if (!ErrorInfo.empty()) {
-    errs() << ErrorInfo << "\n";
+  std::error_code EC;
+  auto OS = llvm::make_unique<raw_fd_ostream>(CoveragePath.str(), EC,
+                                              sys::fs::F_Text);
+  if (EC) {
+    errs() << EC.message() << "\n";
     return llvm::make_unique<raw_null_ostream>();
   }
   return std::move(OS);

lib/LTO/LTOCodeGenerator.cpp

@@ -163,9 +163,9 @@ bool LTOCodeGenerator::writeMergedModules(const char *path,
   applyScopeRestrictions();
 
   // create output file
-  std::string ErrInfo;
-  tool_output_file Out(path, ErrInfo, sys::fs::F_None);
-  if (!ErrInfo.empty()) {
+  std::error_code EC;
+  tool_output_file Out(path, EC, sys::fs::F_None);
+  if (EC) {
     errMsg = "could not open bitcode file for writing: ";
     errMsg += path;
     return false;

lib/MC/MCParser/DarwinAsmParser.cpp

@@ -638,13 +638,13 @@ bool DarwinAsmParser::parseDirectiveSecureLogUnique(StringRef, SMLoc IDLoc) {
   // Open the secure log file if we haven't already.
   raw_ostream *OS = getContext().getSecureLog();
   if (!OS) {
-    std::string Err;
-    OS = new raw_fd_ostream(SecureLogFile, Err,
+    std::error_code EC;
+    OS = new raw_fd_ostream(SecureLogFile, EC,
                             sys::fs::F_Append | sys::fs::F_Text);
-    if (!Err.empty()) {
+    if (EC) {
        delete OS;
        return Error(IDLoc, Twine("can't open secure log file: ") +
-                    SecureLogFile + " (" + Err + ")");
+                               SecureLogFile + " (" + EC.message() + ")");
     }
     getContext().setSecureLog(OS);
   }

lib/Support/Timer.cpp

@@ -66,10 +66,10 @@ raw_ostream *llvm::CreateInfoOutputFile() {
   // each time -stats or -time-passes wants to print output to it. To
   // compensate for this, the test-suite Makefiles have code to delete the
   // info output file before running commands which write to it.
-  std::string Error;
-  raw_ostream *Result = new raw_fd_ostream(
-      OutputFilename.c_str(), Error, sys::fs::F_Append | sys::fs::F_Text);
-  if (Error.empty())
+  std::error_code EC;
+  raw_ostream *Result = new raw_fd_ostream(OutputFilename, EC,
+                                           sys::fs::F_Append | sys::fs::F_Text);
+  if (!EC)
     return Result;
 
   errs() << "Error opening info-output-file '"

lib/Support/ToolOutputFile.cpp

@@ -16,8 +16,8 @@
 #include "llvm/Support/Signals.h"
 using namespace llvm;
 
-tool_output_file::CleanupInstaller::CleanupInstaller(const char *filename)
-  : Filename(filename), Keep(false) {
+tool_output_file::CleanupInstaller::CleanupInstaller(StringRef Filename)
+    : Filename(Filename), Keep(false) {
   // Arrange for the file to be deleted if the process is killed.
   if (Filename != "-")
     sys::RemoveFileOnSignal(Filename);
@@ -34,14 +34,13 @@ tool_output_file::CleanupInstaller::~CleanupInstaller() {
     sys::DontRemoveFileOnSignal(Filename);
 }
 
-tool_output_file::tool_output_file(const char *filename, std::string &ErrorInfo,
+tool_output_file::tool_output_file(StringRef Filename, std::error_code &EC,
                                    sys::fs::OpenFlags Flags)
-    : Installer(filename), OS(filename, ErrorInfo, Flags) {
+    : Installer(Filename), OS(Filename, EC, Flags) {
   // If open fails, no cleanup is needed.
-  if (!ErrorInfo.empty())
+  if (EC)
     Installer.Keep = true;
 }
 
-tool_output_file::tool_output_file(const char *Filename, int FD)
-    : Installer(Filename), OS(FD, true) {
-}
+tool_output_file::tool_output_file(StringRef Filename, int FD)
+    : Installer(Filename), OS(FD, true) {}

lib/Support/raw_ostream.cpp

@@ -426,20 +426,14 @@ void format_object_base::home() {
 //  raw_fd_ostream
 //===----------------------------------------------------------------------===//
 
-/// raw_fd_ostream - Open the specified file for writing. If an error
-/// occurs, information about the error is put into ErrorInfo, and the
-/// stream should be immediately destroyed; the string will be empty
-/// if no error occurred.
-raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
+raw_fd_ostream::raw_fd_ostream(StringRef Filename, std::error_code &EC,
                                sys::fs::OpenFlags Flags)
     : Error(false), UseAtomicWrites(false), pos(0) {
-  assert(Filename && "Filename is null");
-  ErrorInfo.clear();
-
+  EC = std::error_code();
   // Handle "-" as stdout. Note that when we do this, we consider ourself
   // the owner of stdout. This means that we can do things like close the
   // file descriptor when we're done and set the "binary" flag globally.
-  if (Filename[0] == '-' && Filename[1] == 0) {
+  if (Filename == "-") {
     FD = STDOUT_FILENO;
     // If user requested binary then put stdout into binary mode if
     // possible.
@@ -450,11 +444,9 @@ raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
     return;
   }
 
-  std::error_code EC = sys::fs::openFileForWrite(Filename, FD, Flags);
+  EC = sys::fs::openFileForWrite(Filename, FD, Flags);
 
   if (EC) {
-    ErrorInfo = "Error opening output file '" + std::string(Filename) + "': " +
-                EC.message();
     ShouldClose = false;
     return;
   }

lib/TableGen/Main.cpp

@@ -56,11 +56,11 @@ static int createDependencyFile(const TGParser &Parser, const char *argv0) {
     errs() << argv0 << ": the option -d must be used together with -o\n";
     return 1;
   }
-  std::string Error;
-  tool_output_file DepOut(DependFilename.c_str(), Error, sys::fs::F_Text);
-  if (!Error.empty()) {
-    errs() << argv0 << ": error opening " << DependFilename
-      << ":" << Error << "\n";
+  std::error_code EC;
+  tool_output_file DepOut(DependFilename, EC, sys::fs::F_Text);
+  if (EC) {
+    errs() << argv0 << ": error opening " << DependFilename << ":"
+           << EC.message() << "\n";
     return 1;
   }
   DepOut.os() << OutputFilename << ":";
@@ -101,11 +101,11 @@ int TableGenMain(char *argv0, TableGenMainFn *MainFn) {
   if (Parser.ParseFile())
     return 1;
 
-  std::string Error;
-  tool_output_file Out(OutputFilename.c_str(), Error, sys::fs::F_Text);
-  if (!Error.empty()) {
-    errs() << argv0 << ": error opening " << OutputFilename
-      << ":" << Error << "\n";
+  std::error_code EC;
+  tool_output_file Out(OutputFilename, EC, sys::fs::F_Text);
+  if (EC) {
+    errs() << argv0 << ": error opening " << OutputFilename << ":"
+           << EC.message() << "\n";
     return 1;
   }
   if (!DependFilename.empty()) {

lib/Target/TargetMachineC.cpp

@@ -223,10 +223,10 @@ static LLVMBool LLVMTargetMachineEmit(LLVMTargetMachineRef T, LLVMModuleRef M,
 
 LLVMBool LLVMTargetMachineEmitToFile(LLVMTargetMachineRef T, LLVMModuleRef M,
   char* Filename, LLVMCodeGenFileType codegen, char** ErrorMessage) {
-  std::string error;
-  raw_fd_ostream dest(Filename, error, sys::fs::F_None);
-  if (!error.empty()) {
-    *ErrorMessage = strdup(error.c_str());
+  std::error_code EC;
+  raw_fd_ostream dest(Filename, EC, sys::fs::F_None);
+  if (EC) {
+    *ErrorMessage = strdup(EC.message().c_str());
     return true;
   }
   formatted_raw_ostream destf(dest);