DRTVWR-476: Partially revert 978e09882565: undo using LLTempRedirect.

But leave LLTempRedirect available in the code base.

indra/llcommon/llerror.cpp

@@ -39,6 +39,8 @@
 #if !LL_WINDOWS
 # include <syslog.h>
 # include <unistd.h>
+#else
+# include <io.h>
 #endif // !LL_WINDOWS
 #include <vector>
 #include "string.h"
@@ -52,7 +54,20 @@
 #include "llsingleton.h"
 #include "llstl.h"
 #include "lltimer.h"
-#include "lltempredirect.h"
+
+#if LL_WINDOWS
+#define fhclose  _close
+#define fhdup    _dup
+#define fhdup2   _dup2
+#define fhfdopen _fdopen
+#define fhfileno _fileno
+#else
+#define fhclose  ::close
+#define fhdup    ::dup
+#define fhdup2   ::dup2
+#define fhfdopen ::fdopen
+#define fhfileno ::fileno
+#endif
 
 namespace LLError
 {
@@ -65,6 +80,7 @@ namespace LLError
 		LLSINGLETON(Settings);
 	public:
 		SettingsConfigPtr getSettingsConfig();
+		~Settings();
 
 		void reset();
 		SettingsStoragePtr saveAndReset();
@@ -74,7 +90,7 @@ namespace LLError
 
 	private:
 		SettingsConfigPtr mSettingsConfig;
-		LLTempRedirect mRedirect;
+		int mDupStderr;
 	};
 
 } // namespace LLError
@@ -146,7 +162,8 @@ namespace {
 	public:
 		RecordToFile(const std::string& filename):
 			mName(filename),
-			mFile(LLFile::fopen(filename, "a"))
+			mFile(LLFile::fopen(filename, "a")),
+			mSavedStderr(LLError::Settings::instance().getDupStderr())
 		{
 			if (!mFile)
 			{
@@ -157,13 +174,16 @@ namespace {
 				// We use a number of classic-C libraries, some of which write
 				// log output to stderr. The trouble with that is that unless
 				// you launch the viewer from a console, stderr output is
-				// lost. Redirect stderr to write into this log file.
-				mRedirect = LLTempRedirect(mFile, stderr);
+				// lost. Redirect STDERR_FILENO to write into this log file.
+				fhdup2(fhfileno(mFile), fhfileno(stderr));
 			}
 		}
 
 		~RecordToFile()
 		{
+			// restore stderr to its original fileno so any subsequent output
+			// to stderr goes to original stream
+			fhdup2(mSavedStderr, fhfileno(stderr));
 			mFile.close();
 		}
 
@@ -194,7 +214,7 @@ namespace {
 	private:
 		const std::string mName;
 		LLUniqueFile mFile;
-		LLTempRedirect mRedirect;
+		int mSavedStderr;
 	};
 
 
@@ -205,7 +225,7 @@ namespace {
 			mUseANSI(checkANSI()),
 			// use duplicate stderr file handle so THIS output isn't affected
 			// by our internal redirection of all (other) stderr output
-			mStderr(llfd::open(LLError::Settings::instance().getDupStderr(), "a"))
+			mStderr(fhfdopen(LLError::Settings::instance().getDupStderr(), "a"))
 		{
 			this->showMultiline(true);
 		}
@@ -256,7 +276,7 @@ namespace {
 			// Check whether it's okay to use ANSI; if stderr is
 			// a tty then we assume yes.  Can be turned off with
 			// the LL_NO_ANSI_COLOR env var.
-			return (0 != isatty(fileno(stderr))) &&
+			return (0 != isatty(fhfileno(stderr))) &&
 				(NULL == getenv("LL_NO_ANSI_COLOR"));
 #endif // LL_LINUX
 			return false;
@@ -552,10 +572,18 @@ namespace LLError
 	Settings::Settings():
 		mSettingsConfig(new SettingsConfig()),
 		// duplicate stderr file handle right away
-		mRedirect(NULL, stderr)
+		mDupStderr(fhdup(fhfileno(stderr)))
 	{
 	}
 
+	Settings::~Settings()
+	{
+		// restore original stderr
+		fhdup2(mDupStderr, fhfileno(stderr));
+		// and close the duplicate
+		fhclose(mDupStderr);
+	}
+
 	SettingsConfigPtr Settings::getSettingsConfig()
 	{
 		return mSettingsConfig;
@@ -583,7 +611,7 @@ namespace LLError
 
 	int Settings::getDupStderr() const
 	{
-		return mRedirect.getOriginalTarget();
+		return mDupStderr;
 	}
 
 	bool is_available()