Slic open before flush

RELEASE-NOTES.md

@@ -20,6 +20,9 @@ The Axom project release numbers follow [Semantic Versioning](http://semver.org/
 ## [Unreleased] - Release date yyyy-mm-dd
 
 ### Added
+- SLIC constructors added to streams that take in a `std::string`. If string is
+  interpreted as a file name, the file is not opened until SLIC flushes and the
+  stream has at least one message logged.
 - Primal: Adds a `clip()` operator overload for clipping a 2D polygon against
   another 2D polygon.
 - Primal: Adds `Polygon::reverseOrientation()` to reverse orientation of

src/axom/slic/streams/GenericOutputStream.cpp

@@ -12,29 +12,46 @@ namespace axom
 {
 namespace slic
 {
-GenericOutputStream::GenericOutputStream(std::ostream* os) : m_stream(os) { }
+GenericOutputStream::GenericOutputStream(std::ostream* os)
+  : m_stream(os)
+  , m_file_name()
+  , m_opened(true)
+  , m_isOstreamOwnedBySLIC(false)
+{ }
 
 //------------------------------------------------------------------------------
 GenericOutputStream::GenericOutputStream(const std::string& stream)
 {
   if(stream == "cout")
   {
     m_stream = &std::cout;
+    m_file_name = std::string();
+    m_opened = true;
+    m_isOstreamOwnedBySLIC = false;
   }
   else if(stream == "cerr")
   {
     m_stream = &std::cerr;
+    m_file_name = std::string();
+    m_opened = true;
+    m_isOstreamOwnedBySLIC = false;
   }
   else
   {
-    m_stream = new std::ofstream(stream);
+    m_stream = new std::ostringstream();
+    m_file_name = stream;
+    m_opened = false;
+    m_isOstreamOwnedBySLIC = true;
   }
 }
 
 //------------------------------------------------------------------------------
 GenericOutputStream::GenericOutputStream(std::ostream* os,
                                          const std::string& format)
   : m_stream(os)
+  , m_file_name()
+  , m_opened(true)
+  , m_isOstreamOwnedBySLIC(false)
 {
   this->setFormatString(format);
 }
@@ -53,7 +70,14 @@ GenericOutputStream::GenericOutputStream(const std::string& stream,
 }
 
 //------------------------------------------------------------------------------
-GenericOutputStream::~GenericOutputStream() { }
+GenericOutputStream::~GenericOutputStream()
+{
+  if(m_isOstreamOwnedBySLIC)
+  {
+    delete m_stream;
+    m_stream = static_cast<std::ostream*>(nullptr);
+  }
+}
 
 //------------------------------------------------------------------------------
 void GenericOutputStream::append(message::Level msgLevel,
@@ -80,10 +104,40 @@ void GenericOutputStream::append(message::Level msgLevel,
 }
 
 //------------------------------------------------------------------------------
-void GenericOutputStream::outputLocal() { m_stream->flush(); }
+void GenericOutputStream::openBeforeFlush()
+{
+  if(m_isOstreamOwnedBySLIC && !m_opened)
+  {
+    std::ostringstream* oss = dynamic_cast<std::ostringstream*>(m_stream);
+    if(oss != nullptr)
+    {
+      // Converting stream from ostringstream to ofstream and
+      // writing ostringstream's string buffer to ofstream
+      std::string buffer = oss->str();
+      if(!buffer.empty())
+      {
+        delete m_stream;
+        m_stream = new std::ofstream(m_file_name);
+        (*m_stream) << buffer;
+        m_opened = true;
+      }
+    }
+  }
+}
 
 //------------------------------------------------------------------------------
-void GenericOutputStream::flush() { m_stream->flush(); }
+void GenericOutputStream::outputLocal()
+{
+  openBeforeFlush();
+  m_stream->flush();
+}
+
+//------------------------------------------------------------------------------
+void GenericOutputStream::flush()
+{
+  openBeforeFlush();
+  m_stream->flush();
+}
 
 } /* namespace slic */
 

src/axom/slic/streams/GenericOutputStream.hpp

@@ -49,6 +49,9 @@ class GenericOutputStream : public LogStream
    *   - "cerr" makes std::cerr the output stream
    *   - Any other input will construct a std::ofstream associated with input
    * \param [in] stream the string to control type of stream created
+   *
+   * \note This constructor avoids creating an empty file if this
+   *       GenericOutputStream never flushes a message.
    */
   GenericOutputStream(const std::string& stream);
 
@@ -57,20 +60,24 @@ class GenericOutputStream : public LogStream
    *  message formatting.
    * \param [in] os pointer to a user-supplied ostream instance.
    * \param [in] format the format string.
+   * \pre os != NULL
    * \see LogStream::setFormatString for the format string.
    */
   GenericOutputStream(std::ostream* os, const std::string& format);
 
   /*!
    * \brief Constructs a GenericOutputStream instance specified by the given
-   *  string  and message formatting.
+   *  string and message formatting.
    *  The string input determines the stream as follows:
    *   - "cout" makes std::cout the output stream
    *   - "cerr" makes std::cerr the output stream
    *   - Any other input will construct a std::ofstream associated with input
    * \param [in] stream the string to control type of stream created
    * \param [in] format the format string.
    * \see LogStream::setFormatString for the format string.
+   *
+   * \note This constructor avoids creating an empty file if this
+   *       GenericOutputStream never flushes a message.
    */
   GenericOutputStream(const std::string& stream, const std::string& format);
 
@@ -100,12 +107,25 @@ class GenericOutputStream : public LogStream
 
 private:
   std::ostream* m_stream;
+  std::string m_file_name;
+  bool m_opened;
+  bool m_isOstreamOwnedBySLIC;
 
   /*!
    * \brief Default constructor.
    * \note Made private to prevent applications from using it.
    */
-  GenericOutputStream() : m_stream(static_cast<std::ostream*>(nullptr)) {};
+  GenericOutputStream()
+    : m_stream(static_cast<std::ostream*>(nullptr))
+    , m_file_name()
+    , m_opened(false)
+    , m_isOstreamOwnedBySLIC(false) {};
+
+  /*!
+   * \brief Opens a file before flushing stream when GenericOutputStream
+   *        has ownership of ostream to a file (std::string constructor)
+   */
+  void openBeforeFlush();
 
   DISABLE_COPY_AND_ASSIGNMENT(GenericOutputStream);
   DISABLE_MOVE_AND_ASSIGNMENT(GenericOutputStream);

src/axom/slic/streams/LumberjackStream.cpp

@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "axom/core/Macros.hpp"
+#include "axom/core/utilities/StringUtilities.hpp"
 
 #include "axom/lumberjack/BinaryTreeCommunicator.hpp"
 #include "axom/lumberjack/Lumberjack.hpp"
@@ -22,7 +23,10 @@ LumberjackStream::LumberjackStream(std::ostream* stream,
                                    MPI_Comm comm,
                                    int ranksLimit)
   : m_isLJOwnedBySLIC(false)
+  , m_isOstreamOwnedBySLIC(false)
   , m_stream(stream)
+  , m_file_name()
+  , m_opened(true)
 {
   this->initializeLumberjack(comm, ranksLimit);
 }
@@ -33,7 +37,10 @@ LumberjackStream::LumberjackStream(std::ostream* stream,
                                    int ranksLimit,
                                    const std::string& format)
   : m_isLJOwnedBySLIC(false)
+  , m_isOstreamOwnedBySLIC(false)
   , m_stream(stream)
+  , m_file_name()
+  , m_opened(true)
 {
   this->initializeLumberjack(comm, ranksLimit);
   this->setFormatString(format);
@@ -44,7 +51,10 @@ LumberjackStream::LumberjackStream(std::ostream* stream,
                                    axom::lumberjack::Lumberjack* lj)
   : m_lj(lj)
   , m_isLJOwnedBySLIC(false)
+  , m_isOstreamOwnedBySLIC(false)
   , m_stream(stream)
+  , m_file_name()
+  , m_opened(true)
 { }
 
 //------------------------------------------------------------------------------
@@ -53,18 +63,116 @@ LumberjackStream::LumberjackStream(std::ostream* stream,
                                    const std::string& format)
   : m_lj(lj)
   , m_isLJOwnedBySLIC(false)
+  , m_isOstreamOwnedBySLIC(false)
   , m_stream(stream)
+  , m_file_name()
+  , m_opened(true)
 {
   this->setFormatString(format);
 }
 
+//------------------------------------------------------------------------------
+LumberjackStream::LumberjackStream(const std::string stream,
+                                   MPI_Comm comm,
+                                   int ranksLimit)
+{
+  this->initializeLumberjack(comm, ranksLimit);
+
+  if(stream == "cout")
+  {
+    m_isOstreamOwnedBySLIC = false;
+    m_stream = &std::cout;
+    m_file_name = std::string();
+    m_opened = true;
+  }
+  else if(stream == "cerr")
+  {
+    m_isOstreamOwnedBySLIC = false;
+    m_stream = &std::cerr;
+    m_file_name = std::string();
+    m_opened = true;
+  }
+  else
+  {
+    m_isOstreamOwnedBySLIC = true;
+    m_stream = new std::ofstream();
+    m_file_name = stream;
+    m_opened = false;
+  }
+}
+
+//------------------------------------------------------------------------------
+LumberjackStream::LumberjackStream(const std::string stream,
+                                   MPI_Comm comm,
+                                   int ranksLimit,
+                                   const std::string& format)
+  : LumberjackStream::LumberjackStream(stream, comm, ranksLimit)
+{
+  // Fix newline and tab characters if needed
+  std::string format_fixed = axom::utilities::string::replaceAllInstances(
+    axom::utilities::string::replaceAllInstances(format, "\\n", "\n"),
+    "\\t",
+    "\t");
+  this->setFormatString(format_fixed);
+}
+
+//------------------------------------------------------------------------------
+LumberjackStream::LumberjackStream(const std::string stream,
+                                   axom::lumberjack::Lumberjack* lj)
+{
+  m_lj = lj;
+  m_isLJOwnedBySLIC = false;
+
+  if(stream == "cout")
+  {
+    m_isOstreamOwnedBySLIC = false;
+    m_stream = &std::cout;
+    m_file_name = std::string();
+    m_opened = true;
+  }
+  else if(stream == "cerr")
+  {
+    m_isOstreamOwnedBySLIC = false;
+    m_stream = &std::cerr;
+    m_file_name = std::string();
+    m_opened = true;
+  }
+  else
+  {
+    m_isOstreamOwnedBySLIC = true;
+    m_stream = new std::ofstream();
+    m_file_name = stream;
+    m_opened = false;
+  }
+}
+
+//------------------------------------------------------------------------------
+LumberjackStream::LumberjackStream(const std::string stream,
+                                   axom::lumberjack::Lumberjack* lj,
+                                   const std::string& format)
+  : LumberjackStream::LumberjackStream(stream, lj)
+{
+  // Fix newline and tab characters if needed
+  std::string format_fixed = axom::utilities::string::replaceAllInstances(
+    axom::utilities::string::replaceAllInstances(format, "\\n", "\n"),
+    "\\t",
+    "\t");
+  this->setFormatString(format_fixed);
+}
+
 //------------------------------------------------------------------------------
 LumberjackStream::~LumberjackStream()
 {
   if(m_isLJOwnedBySLIC)
   {
     this->finalizeLumberjack();
   }
+
+  if(m_isOstreamOwnedBySLIC)
+  {
+    delete m_stream;
+    m_stream = static_cast<std::ostream*>(nullptr);
+  }
 }
 
 //------------------------------------------------------------------------------
@@ -146,6 +254,16 @@ void LumberjackStream::write(bool local)
         continue;
       }
 
+      if(m_isOstreamOwnedBySLIC && !m_opened)
+      {
+        std::ofstream* ofs = dynamic_cast<std::ofstream*>(m_stream);
+        if(ofs != nullptr)
+        {
+          ofs->open(m_file_name);
+          m_opened = true;
+        }
+      }
+
       (*m_stream) << this->getFormatedMessage(
         message::getLevelAsString(
           static_cast<message::Level>(curr_message->level())),