tdf#67538 XTypeDetection::queryTypeByDescriptor poor performance, part1

Skip creating an intermediary buffer in XStream_impl::readBytes, and
just read directly into the destination.

This is specifically fixing the performance of queryTypeByDescriptor
when called from a basic macro on a local test file.

This takes my test macro from 17.1s to 16.1s.

Change-Id: Iaa7d38c6a90a3b3f01a4b748c4512dd8fda690c7
Reviewed-on: https://gerrit.libreoffice.org/73374
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 4 insertions, 4 deletions

diff --git a/ucb/source/ucp/file/filstr.cxx b/ucb/source/ucp/file/filstr.cxx
index a2419042de45..8b23813abdc4 100644
--- a/ucb/source/ucp/file/filstr.cxx
+++ b/ucb/source/ucp/file/filstr.cxx
@@ -130,10 +130,9 @@ XStream_impl::readBytes(
     if( ! m_nIsOpen )
         throw io::IOException( THROW_WHERE );
 
-    std::unique_ptr<sal_Int8[]> buffer;
     try
     {
-        buffer.reset(new sal_Int8[nBytesToRead]);
+        aData.realloc(nBytesToRead);
     }
     catch (const std::bad_alloc&)
     {
@@ -142,12 +141,13 @@ XStream_impl::readBytes(
     }
 
     sal_uInt64 nrc(0);
-    if(m_aFile.read( buffer.get(),sal_uInt64(nBytesToRead),nrc )
+    if(m_aFile.read( aData.getArray(), sal_uInt64(nBytesToRead), nrc )
        != osl::FileBase::E_None)
     {
         throw io::IOException( THROW_WHERE );
     }
-    aData = uno::Sequence< sal_Int8 > ( buffer.get(), static_cast<sal_uInt32>(nrc) );
+    if (nrc != static_cast<sal_uInt64>(nBytesToRead))
+        aData.realloc(nrc);
     return static_cast<sal_Int32>(nrc);
 }