1 files changed, 136 insertions, 0 deletions
diff --git a/libdimensionxx/cookie-tmpfile.cpp b/libdimensionxx/cookie-tmpfile.cpp
new file mode 100644
index 0000000..ec320d8
--- /dev/null
+++ b/libdimensionxx/cookie-tmpfile.cpp
@@ -0,0 +1,136 @@
+/*************************************************************************
+ * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension Library is distributed in the hope that it will be      *
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty   *
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#include "dimensionxx.hpp"
+#include <stdio.h>
+
+// Use a tmpfile as a buffer for a C++/C I/O interface.
+
+namespace Dimension
+{
+  namespace
+  {
+    void
+    write_cookie(FILE* file, std::istream& istr)
+    {
+      unsigned int count, pos;
+      const unsigned int bs = 8192;
+      char buffer[bs];
+
+      pos = istr.tellg();
+      istr.seekg(0);
+      while (true) {
+        istr.read(buffer, bs);
+        count = istr.gcount();
+
+        if (count != bs) {
+          if (istr.eof()) {
+            fwrite(buffer, 1, count, file);
+            break;
+          } else {
+            throw Dimension_Error("Error reading from input stream.");
+          }
+        }
+
+        fwrite(buffer, 1, bs, file);
+      }
+      fseek(file, pos, SEEK_SET);
+    }
+
+    void
+    read_cookie(std::ostream& ostr, FILE* file)
+    {
+      unsigned int count, pos;
+      const unsigned int bs = 8192;
+      char buffer[bs];
+
+      pos = ftell(file);
+      rewind(file);
+      while (true) {
+        count = fread(buffer, 1, bs, file);
+        if (count != bs) {
+          if (feof(file)) {
+            ostr.write(buffer, count);
+            break;
+          } else {
+            throw Dimension_Error("Error reading from temporary file.");
+          }
+        }
+
+        ostr.write(buffer, bs);
+      }
+      ostr.seekp(pos);
+    }
+  }
+
+  // Make an input FILE_Cookie
+  FILE_Cookie::FILE_Cookie(std::istream& istr)
+    : m_file(tmpfile()), m_istr(&istr), m_ostr(0)
+  {
+    if (!m_file) {
+      throw Dimension_Error("Error opening temporary file for C++/C I/O"
+                            " interface.");
+    }
+
+    write_cookie(m_file, *m_istr);
+  }
+
+  // Make an output FILE_Cookie
+  FILE_Cookie::FILE_Cookie(std::ostream& ostr)
+    : m_file(tmpfile()), m_istr(0), m_ostr(&ostr)
+  {
+    if (!m_file) {
+      throw Dimension_Error("Error opening temporary file for C++/C I/O"
+                            " interface.");
+    }
+  }
+
+  // Make an I/O FILE_Cookie
+  FILE_Cookie::FILE_Cookie(std::iostream& iostr)
+    : m_file(tmpfile()), m_istr(&iostr), m_ostr(&iostr)
+  {
+    if (!m_file) {
+      throw Dimension_Error("Error opening temporary file for C++/C I/O"
+                            " interface.");
+    }
+
+    write_cookie(m_file, *m_istr);
+  }
+
+  // Close the tmpfile, maybe syncing a C++ stream to it first
+  FILE_Cookie::~FILE_Cookie() {
+    if (is_output()) {
+      read_cookie(*m_ostr, m_file);
+    }
+
+    std::fclose(m_file);
+  }
+
+  FILE*       FILE_Cookie::file()       { return m_file; }
+  const FILE* FILE_Cookie::file() const { return m_file; }
+
+  bool FILE_Cookie::is_input()  const { return m_istr; }
+  bool FILE_Cookie::is_output() const { return m_ostr; }
+
+  std::istream&       FILE_Cookie::istr()       { return *m_istr; }
+  const std::istream& FILE_Cookie::istr() const { return *m_istr; }
+  std::ostream&       FILE_Cookie::ostr()       { return *m_ostr; }
+  const std::ostream& FILE_Cookie::ostr() const { return *m_ostr; }
+}