cool#16122 export to pdf produces bad PANTONE element

The name element in a PDF file needs escaping if it contains spaces, like the PANTONE element does.

Re-use the escaping logic in COSWriter, and while we are here, convert
the COSWriter function from 'const char*' to std::string_view.

Change-Id: I4f6fdb049e746688c393371e2fea30bbaf6da314
Signed-off-by: Noel Grandin <noel.grandin@collabora.co.uk>
Reviewed-on: https://gerrit.collaboraoffice.com/c/online/+/10095
Tested-by: Jenkins CPCI <releng@collaboraoffice.com>
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>
(cherry picked from commit 765ae13aa2e7a954a1629314726207f551d83ff8)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/210955
Tested-by: Jenkins
Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>

include/vcl/filter/pdfdocument.hxx

@@ -223,12 +223,7 @@ public:
     const OString& GetValue() const;
     SAL_DLLPRIVATE sal_uInt64 GetLocation() const;
     sal_uInt64 GetLength() const { return m_aValue.getLength(); }
-
-    void writeString(OStringBuffer& rBuffer) override
-    {
-        rBuffer.append("/");
-        rBuffer.append(m_aValue);
-    }
+    void writeString(OStringBuffer& rBuffer) override;
 };
 
 /// Dictionary object: a set of key-value pairs.

vcl/inc/pdf/COSWriter.hxx

@@ -167,7 +167,7 @@ public:
 
     static void appendUnicodeTextString(const OUString& rString, OStringBuffer& rBuffer);
     static void appendName(std::u16string_view rString, OStringBuffer& rBuffer);
-    static void appendName(const char* pString, OStringBuffer& rBuffer);
+    static void appendName(std::string_view aString, OStringBuffer& rBuffer);
 };
 }
 

vcl/qa/cppunit/pdfexport/pdfexport2.cxx

@@ -7156,6 +7156,31 @@ CPPUNIT_TEST_FIXTURE(PdfExportTest2, testDropCapPaint)
     CPPUNIT_ASSERT_DOUBLES_EQUAL(114.53, aRect.at(4).getMinX(), /*delta*/ 2.0);
 }
 
+CPPUNIT_TEST_FIXTURE(PdfExportTest2, cool16122BadPantoneElement)
+{
+    vcl::filter::PDFDocument aDocument;
+    loadFromFile(u"cool16122.odt");
+    save(TestFilter::PDF_WRITER);
+
+    // Parse the export result.
+    SvFileStream aStream(maTempFile.GetURL(), StreamMode::READ);
+    // Previously this would have failed here with "PDFDocument::Tokenize: unexpected 'C' keyword at byte position 280"
+    CPPUNIT_ASSERT(aDocument.Read(aStream));
+
+    // But just to be sure, check that the PANTONE element round-trips properly
+    bool bFound = false;
+    for (const auto& rDocElement : aDocument.GetElements())
+    {
+        if (auto pObject = dynamic_cast<vcl::filter::PDFNameElement*>(rDocElement.get()))
+            if (pObject->GetValue() == "PANTONE 293 C")
+            {
+                bFound = true;
+                break;
+            }
+    }
+    CPPUNIT_ASSERT(bFound);
+}
+
 } // end anonymous namespace
 
 CPPUNIT_PLUGIN_IMPLEMENT();

vcl/source/filter/ipdf/pdfdocument.cxx

@@ -2918,6 +2918,12 @@ bool PDFNameElement::Read(SvStream& rStream)
     return false;
 }
 
+void PDFNameElement::writeString(OStringBuffer& rBuffer)
+{
+    rBuffer.append("/");
+    pdf::COSWriter::appendName(m_aValue, rBuffer); // this does the necessary escaping
+}
+
 const OString& PDFNameElement::GetValue() const { return m_aValue; }
 
 sal_uInt64 PDFNameElement::GetLocation() const { return m_nLocation; }

vcl/source/pdf/COSWriter.cxx

@@ -170,22 +170,21 @@ void COSWriter::appendName(std::u16string_view rStr, OStringBuffer& rBuffer)
     }
 }
 
-void COSWriter::appendName(const char* pStr, OStringBuffer& rBuffer)
+void COSWriter::appendName(std::string_view aStr, OStringBuffer& rBuffer)
 {
     // FIXME i59651 see above
-    while (pStr && *pStr)
+    for (const auto ch : aStr)
     {
-        if ((*pStr >= 'A' && *pStr <= 'Z') || (*pStr >= 'a' && *pStr <= 'z')
-            || (*pStr >= '0' && *pStr <= '9') || *pStr == '-')
+        if ((ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z') || (ch >= '0' && ch <= '9')
+            || ch == '-')
         {
-            rBuffer.append(*pStr);
+            rBuffer.append(ch);
         }
         else
         {
             rBuffer.append('#');
-            appendHex(static_cast<sal_Int8>(*pStr), rBuffer);
+            appendHex(static_cast<sal_Int8>(ch), rBuffer);
         }
-        pStr++;
     }
 }