use more string_view in INetURLObject

Change-Id: I4462f7cf4740fa4d1b129d76a0775f4250f41bbd
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/133555
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

3 files changed, 76 insertions, 74 deletions

diff --git a/tools/qa/cppunit/test_urlobj.cxx b/tools/qa/cppunit/test_urlobj.cxx
index abcd2fe1417b..8402fae5ed55 100644
--- a/tools/qa/cppunit/test_urlobj.cxx
+++ b/tools/qa/cppunit/test_urlobj.cxx
@@ -48,7 +48,7 @@ namespace tools_urlobj
         // this is only demonstration code
         void urlobjTest_001(  )
         {
-            INetURLObject aUrl( OUString( "file://10.10.1.1/sampledir/sample.file" ) );
+            INetURLObject aUrl( u"file://10.10.1.1/sampledir/sample.file" );
             CPPUNIT_ASSERT_EQUAL(INetProtocol::File, aUrl.GetProtocol());
             CPPUNIT_ASSERT_EQUAL(OUString("10.10.1.1"),
                                  aUrl.GetHost(INetURLObject::DecodeMechanism::NONE));
@@ -62,7 +62,7 @@ namespace tools_urlobj
 
         void urlobjTest_004(  )
         {
-            INetURLObject aUrl( OUString( "smb://10.10.1.1/sampledir/sample.file" ) );
+            INetURLObject aUrl( u"smb://10.10.1.1/sampledir/sample.file" );
             CPPUNIT_ASSERT_EQUAL( INetProtocol::Smb, aUrl.GetProtocol(  ) );
             CPPUNIT_ASSERT_EQUAL(OUString("10.10.1.1"),
                                  aUrl.GetHost(INetURLObject::DecodeMechanism::NONE));
@@ -77,7 +77,7 @@ namespace tools_urlobj
         {
             // Test with a username part
             {
-                INetURLObject aUrl( OUString( "vnd.libreoffice.cmis://username@http:%2F%2Ffoo.bar.com:8080%2Fmy%2Fcmis%2Fatom%23repo-id-encoded/path/to/content" ) );
+                INetURLObject aUrl( u"vnd.libreoffice.cmis://username@http:%2F%2Ffoo.bar.com:8080%2Fmy%2Fcmis%2Fatom%23repo-id-encoded/path/to/content" );
                 CPPUNIT_ASSERT_EQUAL( std::string( "http://foo.bar.com:8080/my/cmis/atom#repo-id-encoded" ),
                         OUSTR_TO_STDSTR( aUrl.GetHost( INetURLObject::DecodeMechanism::WithCharset ) ) );
                 CPPUNIT_ASSERT_EQUAL( std::string( "username" ), OUSTR_TO_STDSTR( aUrl.GetUser( ) ) );
@@ -88,8 +88,8 @@ namespace tools_urlobj
 
             // Test without a username part
             {
-                INetURLObject aUrl( OUString(
-                                "vnd.libreoffice.cmis://http:%2F%2Ffoo.bar.com:8080%2Fmy%2Fcmis%2Fatom%23repo-id-encoded/path/to/content" ) );
+                INetURLObject aUrl(
+                                u"vnd.libreoffice.cmis://http:%2F%2Ffoo.bar.com:8080%2Fmy%2Fcmis%2Fatom%23repo-id-encoded/path/to/content" );
                 CPPUNIT_ASSERT_EQUAL( std::string( "http://foo.bar.com:8080/my/cmis/atom#repo-id-encoded" ),
                         OUSTR_TO_STDSTR( aUrl.GetHost( INetURLObject::DecodeMechanism::WithCharset ) ) );
                 CPPUNIT_ASSERT( !aUrl.HasUserData() );
@@ -101,18 +101,18 @@ namespace tools_urlobj
 
         void urlobjTest_emptyPath() {
             {
-                INetURLObject url(OUString("http://example.com"));
+                INetURLObject url(u"http://example.com");
                 CPPUNIT_ASSERT_EQUAL(INetProtocol::Http, url.GetProtocol());
                 CPPUNIT_ASSERT_EQUAL(OUString("example.com"), url.GetHost());
                 CPPUNIT_ASSERT_EQUAL(OUString("/"), url.GetURLPath());
             }
             {
                 // This is an invalid http URL per RFC 2616:
-                INetURLObject url(OUString("http://example.com?query"));
+                INetURLObject url(u"http://example.com?query");
                 CPPUNIT_ASSERT(url.HasError());
             }
             {
-                INetURLObject url(OUString("http://example.com#fragment"));
+                INetURLObject url(u"http://example.com#fragment");
                 CPPUNIT_ASSERT_EQUAL(INetProtocol::Http, url.GetProtocol());
                 CPPUNIT_ASSERT_EQUAL(OUString("example.com"), url.GetHost());
                 CPPUNIT_ASSERT_EQUAL(OUString("/"), url.GetURLPath());
@@ -125,19 +125,19 @@ namespace tools_urlobj
             std::unique_ptr<SvMemoryStream> strm;
             unsigned char const * buf;
 
-            url = INetURLObject("data:");
+            url = INetURLObject(u"data:");
             //TODO: CPPUNIT_ASSERT(url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(!strm);
 
-            url = INetURLObject("data:,");
+            url = INetURLObject(u"data:,");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(strm != nullptr);
             CPPUNIT_ASSERT_EQUAL(sal_uInt64(0), strm->GetSize());
             strm.reset();
 
-            url = INetURLObject("data:,,%C3%A4%90");
+            url = INetURLObject(u"data:,,%C3%A4%90");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(strm != nullptr);
@@ -149,26 +149,26 @@ namespace tools_urlobj
             CPPUNIT_ASSERT_EQUAL(0x90, int(buf[3]));
             strm.reset();
 
-            url = INetURLObject("data:base64,");
+            url = INetURLObject(u"data:base64,");
             //TODO: CPPUNIT_ASSERT(url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(!strm);
 
-            url = INetURLObject("data:;base64,");
+            url = INetURLObject(u"data:;base64,");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(strm != nullptr);
             CPPUNIT_ASSERT_EQUAL(sal_uInt64(0), strm->GetSize());
             strm.reset();
 
-            url = INetURLObject("data:;bAsE64,");
+            url = INetURLObject(u"data:;bAsE64,");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(strm != nullptr);
             CPPUNIT_ASSERT_EQUAL(sal_uInt64(0), strm->GetSize());
             strm.reset();
 
-            url = INetURLObject("data:;base64,YWJjCg==");
+            url = INetURLObject(u"data:;base64,YWJjCg==");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(strm != nullptr);
@@ -180,17 +180,17 @@ namespace tools_urlobj
             CPPUNIT_ASSERT_EQUAL(0x0A, int(buf[3]));
             strm.reset();
 
-            url = INetURLObject("data:;base64,YWJjCg=");
+            url = INetURLObject(u"data:;base64,YWJjCg=");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(!strm);
 
-            url = INetURLObject("data:;base64,YWJ$Cg==");
+            url = INetURLObject(u"data:;base64,YWJ$Cg==");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(!strm);
 
-            url = INetURLObject("data:text/plain;param=%22;base64,%22,YQ==");
+            url = INetURLObject(u"data:text/plain;param=%22;base64,%22,YQ==");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(strm != nullptr);
@@ -202,7 +202,7 @@ namespace tools_urlobj
             CPPUNIT_ASSERT_EQUAL(0x3D, int(buf[3]));
             strm.reset();
 
-            url = INetURLObject("http://example.com");
+            url = INetURLObject(u"http://example.com");
             CPPUNIT_ASSERT(!url.HasError());
             strm = url.getData();
             CPPUNIT_ASSERT(!strm);
@@ -212,62 +212,62 @@ namespace tools_urlobj
             CPPUNIT_ASSERT(INetURLObject().isSchemeEqualTo(INetProtocol::NotValid));
             CPPUNIT_ASSERT(!INetURLObject().isSchemeEqualTo(u""));
             CPPUNIT_ASSERT(
-                INetURLObject("http://example.org").isSchemeEqualTo(
+                INetURLObject(u"http://example.org").isSchemeEqualTo(
                     INetProtocol::Http));
             CPPUNIT_ASSERT(
-                !INetURLObject("http://example.org").isSchemeEqualTo(
+                !INetURLObject(u"http://example.org").isSchemeEqualTo(
                     INetProtocol::Https));
             CPPUNIT_ASSERT(
-                INetURLObject("http://example.org").isSchemeEqualTo(u"Http"));
+                INetURLObject(u"http://example.org").isSchemeEqualTo(u"Http"));
             CPPUNIT_ASSERT(
-                !INetURLObject("http://example.org").isSchemeEqualTo(u"dav"));
+                !INetURLObject(u"http://example.org").isSchemeEqualTo(u"dav"));
             CPPUNIT_ASSERT(
-                INetURLObject("dav://example.org").isSchemeEqualTo(u"dav"));
+                INetURLObject(u"dav://example.org").isSchemeEqualTo(u"dav"));
         }
 
         void urlobjTest_isAnyKnownWebDAVScheme() {
             CPPUNIT_ASSERT(
-                INetURLObject("http://example.org").isAnyKnownWebDAVScheme());
+                INetURLObject(u"http://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                INetURLObject("https://example.org").isAnyKnownWebDAVScheme());
+                INetURLObject(u"https://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                INetURLObject("vnd.sun.star.webdav://example.org").isAnyKnownWebDAVScheme());
+                INetURLObject(u"vnd.sun.star.webdav://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                INetURLObject("vnd.sun.star.webdavs://example.org").isAnyKnownWebDAVScheme());
+                INetURLObject(u"vnd.sun.star.webdavs://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                !INetURLObject("ftp://example.org").isAnyKnownWebDAVScheme());
+                !INetURLObject(u"ftp://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                !INetURLObject("file://example.org").isAnyKnownWebDAVScheme());
+                !INetURLObject(u"file://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                !INetURLObject("dav://example.org").isAnyKnownWebDAVScheme());
+                !INetURLObject(u"dav://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                !INetURLObject("davs://example.org").isAnyKnownWebDAVScheme());
+                !INetURLObject(u"davs://example.org").isAnyKnownWebDAVScheme());
             CPPUNIT_ASSERT(
-                !INetURLObject("vnd.sun.star.pkg://example.org").isAnyKnownWebDAVScheme());
+                !INetURLObject(u"vnd.sun.star.pkg://example.org").isAnyKnownWebDAVScheme());
         }
 
         void testSetName() {
             {
-                INetURLObject obj("file:///");
+                INetURLObject obj(u"file:///");
                 bool ok = obj.setName(u"foo");
                 CPPUNIT_ASSERT(!ok);
             }
             {
-                INetURLObject obj("file:///foo");
+                INetURLObject obj(u"file:///foo");
                 bool ok = obj.setName(u"bar");
                 CPPUNIT_ASSERT(ok);
                 CPPUNIT_ASSERT_EQUAL(
                     OUString("file:///bar"), obj.GetMainURL(INetURLObject::DecodeMechanism::NONE));
             }
             {
-                INetURLObject obj("file:///foo/");
+                INetURLObject obj(u"file:///foo/");
                 bool ok = obj.setName(u"bar");
                 CPPUNIT_ASSERT(ok);
                 CPPUNIT_ASSERT_EQUAL(
                     OUString("file:///bar/"), obj.GetMainURL(INetURLObject::DecodeMechanism::NONE));
             }
             {
-                INetURLObject obj("file:///foo/bar");
+                INetURLObject obj(u"file:///foo/bar");
                 bool ok = obj.setName(u"baz");
                 CPPUNIT_ASSERT(ok);
                 CPPUNIT_ASSERT_EQUAL(
@@ -275,7 +275,7 @@ namespace tools_urlobj
                     obj.GetMainURL(INetURLObject::DecodeMechanism::NONE));
             }
             {
-                INetURLObject obj("file:///foo/bar/");
+                INetURLObject obj(u"file:///foo/bar/");
                 bool ok = obj.setName(u"baz");
                 CPPUNIT_ASSERT(ok);
                 CPPUNIT_ASSERT_EQUAL(
@@ -285,7 +285,7 @@ namespace tools_urlobj
         }
 
         void testSetExtension() {
-            INetURLObject obj("file:///foo/bar.baz/");
+            INetURLObject obj(u"file:///foo/bar.baz/");
             bool ok = obj.setExtension(
                 u"other", INetURLObject::LAST_SEGMENT, false);
             CPPUNIT_ASSERT(ok);
@@ -295,7 +295,7 @@ namespace tools_urlobj
         }
 
         void testChangeScheme() {
-            INetURLObject obj("unknown://example.com/foo/bar");
+            INetURLObject obj(u"unknown://example.com/foo/bar");
             CPPUNIT_ASSERT(!obj.HasError());
             obj.changeScheme(INetProtocol::Http);
             CPPUNIT_ASSERT_EQUAL(
@@ -312,7 +312,7 @@ namespace tools_urlobj
         }
 
         void testTd146382() {
-            INetURLObject obj("file://share.allotropia.de@SSL/DavWWWRoot/remote.php");
+            INetURLObject obj(u"file://share.allotropia.de@SSL/DavWWWRoot/remote.php");
             CPPUNIT_ASSERT(!obj.HasError());
             CPPUNIT_ASSERT_EQUAL(
                 OUString("file://share.allotropia.de@SSL/DavWWWRoot/remote.php"),
@@ -323,7 +323,7 @@ namespace tools_urlobj
         {
             {
                 // host:port must not be misinterpreted as scheme:path
-                INetURLObject obj("example.com:8080/foo", INetProtocol::Http);
+                INetURLObject obj(u"example.com:8080/foo", INetProtocol::Http);
                 CPPUNIT_ASSERT(!obj.HasError());
                 CPPUNIT_ASSERT_EQUAL(OUString("http://example.com:8080/foo"),
                     obj.GetMainURL(INetURLObject::DecodeMechanism::NONE));
@@ -334,7 +334,7 @@ namespace tools_urlobj
             }
             {
                 // port may only contain decimal digits, so this must be treated as unknown scheme
-                INetURLObject obj("example.com:80a0/foo", INetProtocol::Http);
+                INetURLObject obj(u"example.com:80a0/foo", INetProtocol::Http);
                 CPPUNIT_ASSERT(!obj.HasError());
                 CPPUNIT_ASSERT_EQUAL(OUString("example.com:80a0/foo"),
                     obj.GetMainURL(INetURLObject::DecodeMechanism::NONE));
diff --git a/tools/source/fsys/urlobj.cxx b/tools/source/fsys/urlobj.cxx
index a4bc5ab0922d..4d7a73999e7f 100644
--- a/tools/source/fsys/urlobj.cxx
+++ b/tools/source/fsys/urlobj.cxx
@@ -719,14 +719,14 @@ OUString parseScheme(
 
 }
 
-bool INetURLObject::setAbsURIRef(OUString const & rTheAbsURIRef,
+bool INetURLObject::setAbsURIRef(std::u16string_view rTheAbsURIRef,
                                  EncodeMechanism eMechanism,
                                  rtl_TextEncoding eCharset,
                                  bool bSmart,
                                  FSysStyle eStyle)
 {
-    sal_Unicode const * pPos = rTheAbsURIRef.getStr();
-    sal_Unicode const * pEnd = pPos + rTheAbsURIRef.getLength();
+    sal_Unicode const * pPos = rTheAbsURIRef.data();
+    sal_Unicode const * pEnd = pPos + rTheAbsURIRef.size();
 
     setInvalid();
 
@@ -3200,13 +3200,13 @@ failed:
     return false;
 }
 
-bool INetURLObject::setPath(OUString const & rThePath,
+bool INetURLObject::setPath(std::u16string_view rThePath,
                             EncodeMechanism eMechanism,
                             rtl_TextEncoding eCharset)
 {
     OUStringBuffer aSynPath(256);
-    sal_Unicode const * p = rThePath.getStr();
-    sal_Unicode const * pEnd = p + rThePath.getLength();
+    sal_Unicode const * p = rThePath.data();
+    sal_Unicode const * pEnd = p + rThePath.size();
     if (!parsePath(m_eScheme, &p, pEnd, eMechanism, eCharset, false,
                    '/', 0x80000000, 0x80000000, 0x80000000, aSynPath)
         || p != pEnd)
@@ -3773,7 +3773,7 @@ bool INetURLObject::ConcatData(INetProtocol eTheScheme,
                                std::u16string_view rThePassword,
                                std::u16string_view rTheHost,
                                sal_uInt32 nThePort,
-                               OUString const & rThePath)
+                               std::u16string_view rThePath)
 {
     setInvalid();
     m_eScheme = eTheScheme;
@@ -3885,8 +3885,8 @@ bool INetURLObject::ConcatData(INetProtocol eTheScheme,
         }
     }
     OUStringBuffer aSynPath(256);
-    sal_Unicode const * p = rThePath.getStr();
-    sal_Unicode const * pEnd = p + rThePath.getLength();
+    sal_Unicode const * p = rThePath.data();
+    sal_Unicode const * pEnd = p + rThePath.size();
     if (!parsePath(m_eScheme, &p, pEnd, EncodeMechanism::WasEncoded, RTL_TEXTENCODING_UTF8, false, '/',
                    0x80000000, 0x80000000, 0x80000000, aSynPath)
         || p != pEnd)
@@ -3900,7 +3900,7 @@ bool INetURLObject::ConcatData(INetProtocol eTheScheme,
 }
 
 // static
-OUString INetURLObject::GetAbsURL(OUString const & rTheBaseURIRef,
+OUString INetURLObject::GetAbsURL(std::u16string_view rTheBaseURIRef,
                                        OUString const & rTheRelURIRef,
                                        EncodeMechanism eEncodeMechanism,
                                        DecodeMechanism eDecodeMechanism,
@@ -4102,9 +4102,9 @@ bool INetURLObject::setName(std::u16string_view rTheName, EncodeMechanism eMecha
         ++p;
 
     return setPath(
-        std::u16string_view(pPathBegin, pSegBegin - pPathBegin)
+        rtl::OUStringConcatenation(std::u16string_view(pPathBegin, pSegBegin - pPathBegin)
             + encodeText(rTheName, PART_PCHAR, eMechanism, eCharset, true)
-            + std::u16string_view(p, pPathEnd - p),
+            + std::u16string_view(p, pPathEnd - p)),
         EncodeMechanism::NotCanonical,
         RTL_TEXTENCODING_UTF8);
 }
@@ -4179,9 +4179,9 @@ bool INetURLObject::setBase(std::u16string_view rTheBase, sal_Int32 nIndex,
         pExtension = p;
 
     return setPath(
-        std::u16string_view(pPathBegin, pSegBegin - pPathBegin)
+        rtl::OUStringConcatenation(std::u16string_view(pPathBegin, pSegBegin - pPathBegin)
             + encodeText(rTheBase, PART_PCHAR, eMechanism, eCharset, true)
-            + std::u16string_view(pExtension, pPathEnd - pExtension),
+            + std::u16string_view(pExtension, pPathEnd - pExtension)),
         EncodeMechanism::NotCanonical,
         RTL_TEXTENCODING_UTF8);
 }
@@ -4239,9 +4239,9 @@ bool INetURLObject::setExtension(std::u16string_view rTheExtension,
         pExtension = p;
 
     return setPath(
-        OUString::Concat(std::u16string_view(pPathBegin, pExtension - pPathBegin)) + "."
+        rtl::OUStringConcatenation(OUString::Concat(std::u16string_view(pPathBegin, pExtension - pPathBegin)) + "."
             + encodeText(rTheExtension, PART_PCHAR, EncodeMechanism::WasEncoded, eCharset, true)
-            + std::u16string_view(p, pPathEnd - p),
+            + std::u16string_view(p, pPathEnd - p)),
         EncodeMechanism::NotCanonical,
         RTL_TEXTENCODING_UTF8);
 }
diff --git a/tools/source/inet/inetmsg.cxx b/tools/source/inet/inetmsg.cxx
index bb8a700d16f1..d58581e74200 100644
--- a/tools/source/inet/inetmsg.cxx
+++ b/tools/source/inet/inetmsg.cxx
@@ -22,6 +22,8 @@
 #include <tools/inetmsg.hxx>
 #include <comphelper/string.hxx>
 #include <rtl/character.hxx>
+#include <o3tl/safeint.hxx>
+#include <o3tl/string_view.hxx>
 
 #include <map>
 
@@ -52,32 +54,32 @@ static const char *months[12] =
     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 };
 
-static sal_uInt16 ParseNumber(const OString& rStr, sal_Int32& nIndex)
+static sal_uInt16 ParseNumber(std::string_view rStr, size_t& nIndex)
 {
-    sal_Int32 n = nIndex;
-    while ((n < rStr.getLength())
+    size_t n = nIndex;
+    while ((n < rStr.size())
            && rtl::isAsciiDigit(static_cast<unsigned char>(rStr[n])))
         n++;
 
-    OString aNum(rStr.copy(nIndex, (n - nIndex)));
+    std::string_view aNum(rStr.substr(nIndex, (n - nIndex)));
     nIndex = n;
 
-    return static_cast<sal_uInt16>(aNum.toInt32());
+    return static_cast<sal_uInt16>(o3tl::toInt32(aNum));
 }
 
-static sal_uInt16 ParseMonth(const OString& rStr, sal_Int32& nIndex)
+static sal_uInt16 ParseMonth(std::string_view rStr, size_t& nIndex)
 {
-    sal_Int32 n = nIndex;
-    while ((n < rStr.getLength())
+    size_t n = nIndex;
+    while ((n < rStr.size())
            && rtl::isAsciiAlpha(static_cast<unsigned char>(rStr[n])))
         n++;
 
-    OString aMonth(rStr.copy(nIndex, 3));
+    std::string_view aMonth(rStr.substr(nIndex, 3));
     nIndex = n;
 
     sal_uInt16 i;
     for (i = 0; i < 12; i++)
-        if (aMonth.equalsIgnoreAsciiCase(months[i])) break;
+        if (o3tl::equalsIgnoreAsciiCase(aMonth, months[i])) break;
     return (i + 1);
 }
 
@@ -92,20 +94,20 @@ bool INetMIMEMessage::ParseDateField (
     if (aDateField.indexOf(':') != -1)
     {
         // Some DateTime format.
-        sal_Int32 nIndex = 0;
+        size_t nIndex = 0;
 
         // Skip over <Wkd> or <Weekday>, leading and trailing space.
-        while ((nIndex < aDateField.getLength()) &&
+        while ((nIndex < o3tl::make_unsigned(aDateField.getLength())) &&
                (aDateField[nIndex] == ' '))
             nIndex++;
 
         while (
-            (nIndex < aDateField.getLength()) &&
+            (nIndex < o3tl::make_unsigned(aDateField.getLength())) &&
             (rtl::isAsciiAlpha (static_cast<unsigned char>(aDateField[nIndex])) ||
              (aDateField[nIndex] == ',')     ))
             nIndex++;
 
-        while ((nIndex < aDateField.getLength()) &&
+        while ((nIndex < o3tl::make_unsigned(aDateField.getLength())) &&
                (aDateField[nIndex] == ' '))
             nIndex++;
 
@@ -143,7 +145,7 @@ bool INetMIMEMessage::ParseDateField (
             rDateTime.SetSec    (ParseNumber (aDateField, nIndex)); nIndex++;
             rDateTime.SetNanoSec (0);
 
-            const char cPossiblePlusMinus = nIndex < aDateField.getLength() ? aDateField[nIndex] : 0;
+            const char cPossiblePlusMinus = nIndex < o3tl::make_unsigned(aDateField.getLength()) ? aDateField[nIndex] : 0;
             if (cPossiblePlusMinus == '+' || cPossiblePlusMinus == '-')
             {
                 // Offset from GMT: "(+|-)HHMM".