[svn-r26667] Purpose: Fixed HDFFV-8766

Description:
    Per user Jason Newton request, the following constructor is added:
        H5File(hid_t existing_id);
    Also, fixed H5File::openFile to close current file first before re-using
    the object.
Platforms tested:
    Linux/64 (platypus)
    Linux/32 2.6 (jam gnu and Intel 15.0)
    SunOS 5.11 (emu)

3 files changed, 56 insertions, 0 deletions

diff --git a/c++/src/H5File.cpp b/c++/src/H5File.cpp
index e0a0da5..7ca126f 100644
--- a/c++/src/H5File.cpp
+++ b/c++/src/H5File.cpp
@@ -158,6 +158,25 @@ void H5File::p_get_file(const char* name, unsigned int flags, const FileCreatPro
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 //--------------------------------------------------------------------------
+// Function:	H5File overloaded constructor
+///\brief	Creates an H5File object using an existing file id.
+///\param	existing_id - IN: Id of an existing file
+// Programmer	Binh-Minh Ribler - 2015
+// Description
+//	Mar 29, 2015
+//		Added in responding to a request from user Jason Newton.
+//		However, it is not recommended to use the private member "id"
+//		in applications.  Unlike other situations, where similar
+//		constructor is needed by the library in order to return
+//		an object, H5File doesn't need it. -BMR (HDFFV-8766 partially)
+//--------------------------------------------------------------------------
+H5File::H5File(hid_t existing_id) : H5Location(), CommonFG()
+{
+    id = existing_id;
+    incRefCount(); // increment number of references to this id
+}
+
+//--------------------------------------------------------------------------
 // Function:	H5File copy constructor
 ///\brief	Copy constructor: makes a copy of the original
 ///		H5File object.
@@ -225,6 +244,13 @@ bool H5File::isHdf5(const H5std_string& name )
 //--------------------------------------------------------------------------
 void H5File::openFile(const char* name, unsigned int flags, const FileAccPropList& access_plist)
 {
+    try {
+        close();
+    }
+    catch (Exception close_error) {
+        throw FileIException("H5File::openFile", close_error.getDetailMsg());
+    }
+
     hid_t access_plist_id = access_plist.getId();
     id = H5Fopen (name, flags, access_plist_id);
     if (id < 0)  // throw an exception when open fails
diff --git a/c++/src/H5File.h b/c++/src/H5File.h
index 0ef85b5..29621aa 100644
--- a/c++/src/H5File.h
+++ b/c++/src/H5File.h
@@ -84,6 +84,10 @@ class H5_DLLCPP H5File : public H5Location, public CommonFG {
 	// Gets the file id
 	virtual hid_t getLocId() const;
 
+	// Creates an H5File using an existing file id.  Not recommended
+	// in applications.
+	H5File(hid_t existing_id);
+
 #endif // DOXYGEN_SHOULD_SKIP_THIS
 
 	///\brief Returns this class name.
diff --git a/c++/test/tfile.cpp b/c++/test/tfile.cpp
index 6d5dc23..f3bbb16 100644
--- a/c++/test/tfile.cpp
+++ b/c++/test/tfile.cpp
@@ -330,6 +330,32 @@ static void test_file_open()
         verify_val(iparm1, F2_SYM_INTERN_K, "FileCreatPropList::getSymk", __LINE__, __FILE__);
         verify_val(iparm2, F2_SYM_LEAF_K, "FileCreatPropList::getSymk", __LINE__, __FILE__);
 
+	// Test H5File constructor with existing file id
+	H5File file2(file1.getId());
+	file1.close();
+
+	// Try truncating the file, and it should fail because the file is
+	// still opened with file2.
+    	try {
+	    H5File file3 (FILE2, H5F_ACC_TRUNC);  // should throw E
+
+	    // Should FAIL but didn't, so throw an invalid action exception
+	    throw InvalidActionException("H5File constructor", "Attempt truncating an opened file.");
+    	}
+	catch( FileIException E ) // catching H5F_ACC_TRUNC on opened file
+	{} // do nothing, FAIL expected
+
+	// Now, really close the file.
+	file2.close();
+
+	// Truncating should succeed now.
+	H5File file3(FILE2, H5F_ACC_TRUNC);
+
+	// Opening another file to file3 object, FILE2 should be closed, so
+	// the next attempt to truncate FILE2 should succeed.
+	file3.openFile(FILE1, H5F_ACC_RDONLY);
+	H5File file4(FILE2, H5F_ACC_TRUNC);
+
 	PASSED();
     }   // end of try block