elide some string copies

Change-Id: I3e0d9f7e5a446689e007b9d01fb1c6bf9bc068e9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/136880
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

avmedia/source/framework/mediaitem.cxx

@@ -406,13 +406,13 @@ CreateStream(uno::Reference<embed::XStorage> const& xStorage,
 
     if (xStorage->hasByName(filename))
     {
-        OUString basename;
-        OUString suffix;
+        std::u16string_view basename;
+        std::u16string_view suffix;
         sal_Int32 const nIndex(rFilename.lastIndexOf('.'));
         if (0 < nIndex)
         {
-            basename = rFilename.copy(0, nIndex);
-            suffix = rFilename.copy(nIndex);
+            basename = rFilename.subView(0, nIndex);
+            suffix = rFilename.subView(nIndex);
         }
         sal_Int32 count(0); // sigh... try to generate non-existent name
         do

basctl/source/basicide/baside2b.cxx

@@ -719,9 +719,9 @@ TextSelection EditorWindow::GetLastHighlightPortionTextSelection() const
     if( aPortions.empty() )
         return TextSelection();
 
-    OUString sStr = aLine.copy( r.nBegin, r.nEnd - r.nBegin );
+    std::u16string_view sStr = aLine.subView( r.nBegin, r.nEnd - r.nBegin );
     TextPaM aStart( nLine, r.nBegin );
-    TextPaM aEnd( nLine, r.nBegin + sStr.getLength() );
+    TextPaM aEnd( nLine, r.nBegin + sStr.size() );
     return TextSelection( aStart, aEnd );
 }
 

basctl/source/basicide/basobj3.cxx

@@ -105,9 +105,7 @@ SbMethod* CreateMacro( SbModule* pModule, const OUString& rMacroName )
             aOUSource = aOUSource.copy( 0, nSourceLen-1 );
     }
 
-    OUString aSubStr = "Sub " + aMacroName + "\n\nEnd Sub";
-
-    aOUSource += aSubStr;
+    aOUSource += "Sub " + aMacroName + "\n\nEnd Sub";
 
     // update module in library
     StarBASIC* pBasic = dynamic_cast<StarBASIC*>(pModule->GetParent());

basctl/source/basicide/bastypes.cxx

@@ -584,9 +584,7 @@ void CutLines( OUString& rStr, sal_Int32 nStartLine, sal_Int32 nLines )
     else
         nEndPos++;
 
-    OUString aEndStr = rStr.copy( nEndPos );
-    rStr = rStr.copy( 0, nStartPos );
-    rStr += aEndStr;
+    rStr = OUString::Concat(rStr.subView( 0, nStartPos )) + rStr.subView( nEndPos );
 
     // erase trailing empty lines
     {
@@ -600,9 +598,7 @@ void CutLines( OUString& rStr, sal_Int32 nStartLine, sal_Int32 nLines )
 
         if ( n > nStartPos )
         {
-            aEndStr = rStr.copy( n );
-            rStr = rStr.copy( 0, nStartPos );
-            rStr += aEndStr;
+            rStr = OUString::Concat(rStr.subView( 0, nStartPos )) + rStr.subView( n );
         }
     }
 }

xmloff/source/style/fonthdl.cxx

@@ -160,7 +160,7 @@ bool XMLFontFamilyNamePropHdl::exportXML( OUString& rStrExpValue, const uno::Any
                     sValue.append( ' ' );
                 }
                 sal_Int32 nLen = nLast-nFirst+1;
-                OUString sFamily( aStrFamilyName.copy( nFirst, nLen ) );
+                std::u16string_view sFamily( aStrFamilyName.subView( nFirst, nLen ) );
                 bool bQuote = false;
                 for( sal_Int32 i=0; i < nLen; i++ )
                 {

xmloff/source/text/txtfldi.cxx

@@ -3323,13 +3323,12 @@ void XMLAnnotationImportContext::PrepareField(
     }
     aDateBuffer.setLength(0);
 
-    OUString sBuffer = aTextBuffer.makeStringAndClear();
-    if ( sBuffer.getLength() )
+    if ( aTextBuffer.getLength() )
     {
         // delete last paragraph mark (if necessary)
-        if (char(0x0a) == sBuffer[sBuffer.getLength()-1])
-            sBuffer = sBuffer.copy(0, sBuffer.getLength()-1);
-        xPropertySet->setPropertyValue(sAPI_content, Any(sBuffer));
+        if (char(0x0a) == aTextBuffer[aTextBuffer.getLength()-1])
+            aTextBuffer.setLength(aTextBuffer.getLength()-1);
+        xPropertySet->setPropertyValue(sAPI_content, Any(aTextBuffer.makeStringAndClear()));
     }
 
     if (!aName.isEmpty())

xmloff/source/transform/DocumentTContext.cxx

@@ -64,20 +64,18 @@ void XMLDocumentTransformerContext::StartElement( const Reference< XAttributeLis
             IsXMLToken( aLocalName, XML_MIMETYPE ) )
         {
             const OUString& rValue = xAttrList->getValueByIndex( i );
-            static const char * aTmp[] =
+            static constexpr std::string_view aTmp[]
             {
                 "application/vnd.oasis.openoffice.",
                 "application/x-vnd.oasis.openoffice.",
                 "application/vnd.oasis.opendocument.",
-                "application/x-vnd.oasis.document.",
-                nullptr
+                "application/x-vnd.oasis.document."
             };
-            for (int k=0; aTmp[k]; k++)
+            for (const auto & rPrefix : aTmp)
             {
-                OUString sTmpString = OUString::createFromAscii(aTmp[k]);
-                if( rValue.matchAsciiL( aTmp[k], sTmpString.getLength() ) )
+                if( rValue.matchAsciiL( rPrefix.data(), rPrefix.size() ) )
                 {
-                    aClass = rValue.copy( sTmpString.getLength() );
+                    aClass = rValue.copy( rPrefix.size() );
                     break;
                 }
             }

xmloff/source/transform/TransformerBase.cxx

@@ -1332,11 +1332,9 @@ bool XMLTransformerBase::ConvertURIToOOo( OUString& rURI,
 
         if( bPackage && bSupportPackage )
         {
-            OUString sTmp( '#' );
             if( rURI.startsWith( "./" ) )
                 rURI = rURI.copy( 2 );
-            sTmp += rURI;
-            rURI = sTmp;
+            rURI = "#" + rURI;
             bRet = true;
         }
     }

xmlsecurity/source/xmlsec/mscrypt/x509certificate_mscryptimpl.cxx

@@ -37,6 +37,7 @@
 #include <osl/nlsupport.h>
 #include <osl/process.h>
 #include <o3tl/char16_t2wchar_t.hxx>
+#include <o3tl/string_view.hxx>
 
 #include <memory>
 #include <string_view>
@@ -77,9 +78,9 @@ findTypeInDN(const OUString& rRawString, std::u16string_view sTypeName)
         {
             if (! bInValue)
             {
-                OUString sType = rRawString.copy(nTypeNameStart, i - nTypeNameStart);
-                sType = sType.trim();
-                if (sType.equalsIgnoreAsciiCase(sTypeName))
+                std::u16string_view sType = rRawString.subView(nTypeNameStart, i - nTypeNameStart);
+                sType = o3tl::trim(sType);
+                if (o3tl::equalsIgnoreAsciiCase(sType, sTypeName))
                 {
                     bFound = true;
                     break;

xmlsecurity/source/xmlsec/nss/sanextension_nssimpl.cxx

@@ -152,9 +152,9 @@ css::uno::Sequence< css::security::CertAltNameEntry > SAL_CALL SanExtensionImpl:
 OString SanExtensionImpl::removeOIDFromString( const OString &oidString)
 {
     OString objID;
-    OString oid("OID.");
+    constexpr std::string_view oid("OID.");
     if (oidString.match(oid))
-        objID = oidString.copy(oid.getLength());
+        objID = oidString.copy(oid.size());
     else
         objID = oidString;
     return objID;

xmlsecurity/source/xmlsec/nss/x509certificate_nssimpl.cxx

@@ -36,6 +36,7 @@
 #include <certificateextension_xmlsecimpl.hxx>
 
 #include "sanextension_nssimpl.hxx"
+#include <o3tl/string_view.hxx>
 #include <tools/time.hxx>
 #include <svl/sigstruct.hxx>
 
@@ -185,9 +186,9 @@ css::uno::Sequence< css::uno::Reference< css::security::XCertificateExtension >
 
             // remove "OID." prefix if existing
             OString objID;
-            OString oid("OID.");
+            constexpr std::string_view oid("OID.");
             if (oidString.match(oid))
-                objID = oidString.copy(oid.getLength());
+                objID = oidString.copy(oid.size());
             else
                 objID = oidString;