Introduce dedicated SwXMLTableContext::MAX_WIDTH, replacing USHRT_MAX

For one, this should make it more obvious what the magic constant USHRT_MAX
meant in the context of SwXMLTableContext::m_nWidth (and shows that it should
arguably have value SAL_MAX_UINT16, not USHRT_MAX).

For another, at least some Android builds are stuck with a broken C library that
defines USHRT_MAX to be of type unsigned int instead of signed int, which caused
various -Wsign-compare that are removed as a side effect.

Change-Id: If2676954f4e7159b0c0d3656b8bc0186f0771e10
Reviewed-on: https://gerrit.libreoffice.org/48661Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Stahl <mstahl@redhat.com>

sw/source/filter/xml/xmltbli.cxx

@@ -1228,6 +1228,10 @@ public:
     }
 };
 
+#if __cplusplus <= 201402
+constexpr sal_Int32 SwXMLTableContext::MAX_WIDTH;
+#endif
+
 const SwXMLTableCell_Impl *SwXMLTableContext::GetCell( sal_uInt32 nRow,
                                                  sal_uInt32 nCol ) const
 {
@@ -1479,8 +1483,8 @@ void SwXMLTableContext::InsertColumn( sal_Int32 nWidth2, bool bRelWidth2,
 
     if( nWidth2 < MINLAY )
         nWidth2 = MINLAY;
-    else if( nWidth2 > USHRT_MAX )
-        nWidth2 = USHRT_MAX;
+    else if( nWidth2 > MAX_WIDTH )
+        nWidth2 = MAX_WIDTH;
     m_aColumnWidths.emplace_back(nWidth2, bRelWidth2 );
     if( (pDfltCellStyleName && !pDfltCellStyleName->isEmpty()) ||
         m_pColumnDefaultCellStyleNames )
@@ -2425,7 +2429,7 @@ void SwXMLTableContext::MakeTable_( SwTableBox *pBox )
             // In this case, the columns get the correct width even if
             // the sum of the relative widths is smaller than the available
             // width in TWIP. Therefore, we can use the relative width.
-            m_nWidth = std::min<sal_Int32>(nRelWidth, USHRT_MAX);
+            m_nWidth = std::min(nRelWidth, MAX_WIDTH);
         }
         if( nRelWidth != m_nWidth && nRelWidth && nCols )
         {
@@ -2679,9 +2683,9 @@ void SwXMLTableContext::MakeTable()
             // of the relative column widths as reference width.
             // Unfortunately this works only if this sum interpreted as
             // twip value is larger than the space that is available.
-            // We don't know that space, so we have to use USHRT_MAX, too.
+            // We don't know that space, so we have to use MAX_WIDTH, too.
             // Even if a size is specified, it will be ignored!
-            m_nWidth = USHRT_MAX;
+            m_nWidth = MAX_WIDTH;
             break;
         default:
             if( pSize )
@@ -2695,14 +2699,14 @@ void SwXMLTableContext::MakeTable()
                 {
                     m_nWidth = pSize->GetWidth();
                     sal_Int32 const min = static_cast<sal_Int32>(
-                        std::min<sal_uInt32>(GetColumnCount() * MINLAY, USHRT_MAX));
+                        std::min<sal_uInt32>(GetColumnCount() * MINLAY, MAX_WIDTH));
                     if( m_nWidth < min )
                     {
                         m_nWidth = min;
                     }
-                    else if( m_nWidth > USHRT_MAX )
+                    else if( m_nWidth > MAX_WIDTH )
                     {
-                        m_nWidth = USHRT_MAX;
+                        m_nWidth = MAX_WIDTH;
                     }
                     m_bRelWidth = false;
                 }
@@ -2712,7 +2716,7 @@ void SwXMLTableContext::MakeTable()
                 eHoriOrient = text::HoriOrientation::LEFT_AND_WIDTH == eHoriOrient
                                     ? text::HoriOrientation::NONE : text::HoriOrientation::FULL;
                 bSetHoriOrient = true;
-                m_nWidth = USHRT_MAX;
+                m_nWidth = MAX_WIDTH;
             }
             break;
         }
@@ -2722,7 +2726,7 @@ void SwXMLTableContext::MakeTable()
     else
     {
         bSetHoriOrient = true;
-        m_nWidth = USHRT_MAX;
+        m_nWidth = MAX_WIDTH;
     }
 
     SwTableLine *pLine1 = m_pTableNode->GetTable().GetTabLines()[0U];

sw/source/filter/xml/xmltbli.hxx

@@ -91,6 +91,11 @@ class SwXMLTableContext : public XMLTextTableContext
     sal_uInt32          m_nCurCol;
     sal_Int32           m_nWidth;
 
+    // The maxiumum table width (i.e., maximum value for m_nWidth); musts be >= MINLAY and must also
+    // fit into ColumnWidthInfo::width (of type sal_uInt16), see e.g. the emplacement of
+    // MINLAY<=nWidht2<=MAX_WIDTH into m_aColumnWidths in SwXMLTableContext::InsertColumn:
+    static constexpr sal_Int32 MAX_WIDTH = SAL_MAX_UINT16;
+
     SwTableBox *NewTableBox( const SwStartNode *pStNd,
                              SwTableLine *pUpper );
     SwTableBox *MakeTableBox( SwTableLine *pUpper,