[llvm-commits] [llvm] r111436 - in /llvm/trunk: include/llvm/Support/raw_ostream.h lib/Support/raw_ostream.cpp

[Dan Gohman]

Author: djg
Date: Wed Aug 18 17:26:19 2010
New Revision: 111436

URL: http://llvm.org/viewvc/llvm-project?rev=111436&view=rev
Log:
Make raw_fd_ostream consider itself the owner of STDOUT_FILENO when
constructed with an output filename of "-". In particular, allow the
file descriptor to be closed, and close the file descriptor in the
destructor if it hasn't been explicitly closed already, to ensure
that any write errors are detected.

Modified:
    llvm/trunk/include/llvm/Support/raw_ostream.h
    llvm/trunk/lib/Support/raw_ostream.cpp

Modified: llvm/trunk/include/llvm/Support/raw_ostream.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/raw_ostream.h?rev=111436&r1=111435&r2=111436&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/raw_ostream.h (original)
+++ llvm/trunk/include/llvm/Support/raw_ostream.h Wed Aug 18 17:26:19 2010
@@ -353,8 +353,11 @@
   /// be immediately destroyed; the string will be empty if no error occurred.
   /// This allows optional flags to control how the file will be opened.
   ///
-  /// \param Filename - The file to open. If this is "-" then the
-  /// stream will use stdout instead.
+  /// 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,
                  unsigned Flags = 0);
 

Modified: llvm/trunk/lib/Support/raw_ostream.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/raw_ostream.cpp?rev=111436&r1=111435&r2=111436&view=diff
==============================================================================
--- llvm/trunk/lib/Support/raw_ostream.cpp (original)
+++ llvm/trunk/lib/Support/raw_ostream.cpp Wed Aug 18 17:26:19 2010
@@ -377,14 +377,17 @@
 
   ErrorInfo.clear();
 
-  // Handle "-" as stdout.
+  // 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) {
     FD = STDOUT_FILENO;
     // If user requested binary then put stdout into binary mode if
     // possible.
     if (Flags & F_Binary)
       sys::Program::ChangeStdoutToBinary();
-    ShouldClose = false;
+    // Close stdout when we're done, to detect any output errors.
+    ShouldClose = true;
     return;
   }