[Boost-commit] svn:boost r42379 - branches/iostreams_dev/libs/iostreams/test

From: technews_at_[hidden]
Date: 2007-12-30 15:24:23

Author: turkanis
Date: 2007-12-30 15:24:23 EST (Sun, 30 Dec 2007)
New Revision: 42379
URL: http://svn.boost.org/trac/boost/changeset/42379

Log:
reimplemented create_large_file() on windows: replaced the painfully slow alternation of writing a char with WriteFile and seeking 1 GB with SetFilePointerEx with an implementation using mapped files that is lightning fast on my development machine. I hate to create a dependence between the file_descriptor tests and the mapped_file tests, but previous implementation sometimes took several minutes to initialize the large file at 9 character offsets
Text files modified: 
   branches/iostreams_dev/libs/iostreams/test/large_file_test.cpp |    43 ++++++++++++++------------------------- 
   1 files changed, 16 insertions(+), 27 deletions(-)

Modified: branches/iostreams_dev/libs/iostreams/test/large_file_test.cpp
==============================================================================
--- branches/iostreams_dev/libs/iostreams/test/large_file_test.cpp	(original)
+++ branches/iostreams_dev/libs/iostreams/test/large_file_test.cpp	2007-12-30 15:24:23 EST (Sun, 30 Dec 2007)
@@ -21,6 +21,7 @@
 #include <boost/iostreams/detail/execute.hpp>
 #include <boost/iostreams/detail/ios.hpp>
 #include <boost/iostreams/device/file_descriptor.hpp>
+#include <boost/iostreams/device/mapped_file.hpp>
 #include <boost/iostreams/positioning.hpp>
 #include <boost/lexical_cast.hpp>
 #include <boost/test/test_tools.hpp>
@@ -150,7 +151,7 @@
     // Fetch last mod date of this file
     string timestamp = 
         "$Date$";
-    if (timestamp.size() != 53) { // Length of SVN auto-generated SVN timestamp
+    if (timestamp.size() != 53) { // Length of auto-generated SVN timestamp
         remove_large_file();
         return false;
     }
@@ -190,10 +191,8 @@
             GENERIC_WRITE,
             0,
             NULL,
-            OPEN_ALWAYS,
-            FILE_ATTRIBUTE_NORMAL | 
-                FILE_FLAG_RANDOM_ACCESS |
-                FILE_FLAG_WRITE_THROUGH,
+            CREATE_ALWAYS,
+            FILE_ATTRIBUTE_NORMAL,
             NULL
         );
     if (!hnd)
@@ -217,35 +216,25 @@
         return false;
     }
 
+    // Close handle; all further access is via mapped_file
+    CloseHandle(hnd);
+
     // Initialize file data
     for (int z = 0; z <= 8; ++z) {
-
-        // Seek
-        length.HighPart = 0;
-        length.LowPart = 0;
-        length.QuadPart = z * gigabyte;
-        LARGE_INTEGER ptr;
-        if ( !SetFilePointerEx(hnd, length, &ptr, FILE_BEGIN) ||
-             ptr.QuadPart != z * gigabyte )
-        {
-            CloseHandle(hnd);
-            remove_large_file();
-            return false;
-        }
-
-        // Write a character
-        char buf[1] = { z + 1 };
-        DWORD result;
-        BOOL success = WriteFile(hnd, buf, 1, &result, NULL);
-        if (!success || result != 1) {
-            CloseHandle(hnd);
-            remove_large_file();
+        try {
+            mapped_file_params params;
+            params.path = file_name;
+            params.offset = z * gigabyte;
+            params.length = 1;
+            params.mode = BOOST_IOS::out;
+            mapped_file file(params);
+            file.begin()[0] = z + 1;
+        } catch (...) {
             return false;
         }
     }
 
     // Close file
-    CloseHandle(hnd);
         return true;
 
 #else // #ifdef BOOST_IOSTREAMS_WINDOWS