Only need an OStringBuffer in number2PolyPolygon

...so that later passing the OStringBuffer's aNum[i] to
createSevenSegmentPolyPolygon (taking a first parameter of type char) doesn't
need to implicitly convert from sal_Unicode to char.

Requires addition of some missing OStringBuffer-related function variants in
rtl/math.hxx and rtl/strbuf.hxx.

Change-Id: I79e6b2a791abc62b6556a6668e4411cced490c11

3 files changed, 64 insertions, 3 deletions

diff --git a/basegfx/source/tools/numbertools.cxx b/basegfx/source/tools/numbertools.cxx
index d30a8371ab2b..86b926ab55d2 100644
--- a/basegfx/source/tools/numbertools.cxx
+++ b/basegfx/source/tools/numbertools.cxx
@@ -12,7 +12,7 @@
 #include <basegfx/polygon/b2dpolypolygon.hxx>
 #include <basegfx/polygon/b2dpolypolygontools.hxx>
 
-#include <rtl/ustrbuf.hxx>
+#include <rtl/strbuf.hxx>
 #include <rtl/math.hxx>
 
 #include <utility>
@@ -27,8 +27,8 @@ namespace basegfx { namespace tools
         // }
         // config here
 
-        rtl::OUStringBuffer aNum;
-        rtl::math::doubleToUStringBuffer(aNum,
+        rtl::OStringBuffer aNum;
+        rtl::math::doubleToStringBuffer(aNum,
                                          fValue,
                                          rtl_math_StringFormat_F,
                                          nDecPlaces, '.',
diff --git a/include/rtl/math.hxx b/include/rtl/math.hxx
index fed674fdd210..7572c972a91f 100644
--- a/include/rtl/math.hxx
+++ b/include/rtl/math.hxx
@@ -21,6 +21,7 @@
 #define INCLUDED_RTL_MATH_HXX
 
 #include <rtl/math.h>
+#include <rtl/strbuf.hxx>
 #include <rtl/string.hxx>
 #include <rtl/ustring.hxx>
 #include <rtl/ustrbuf.hxx>
@@ -63,6 +64,42 @@ inline rtl::OString doubleToString(double fValue, rtl_math_StringFormat eFormat,
     return aResult;
 }
 
+/** A wrapper around rtl_math_doubleToString that appends to an
+    rtl::OStringBuffer.
+
+    @since LibreOffice 5.4
+*/
+inline void doubleToStringBuffer(
+    rtl::OStringBuffer& rBuffer, double fValue, rtl_math_StringFormat eFormat,
+    sal_Int32 nDecPlaces, sal_Char cDecSeparator, sal_Int32 const * pGroups,
+    sal_Char cGroupSeparator, bool bEraseTrailingDecZeros = false)
+{
+    rtl_String ** pData;
+    sal_Int32 * pCapacity;
+    rBuffer.accessInternals(&pData, &pCapacity);
+    rtl_math_doubleToString(
+        pData, pCapacity, rBuffer.getLength(), fValue, eFormat, nDecPlaces,
+        cDecSeparator, pGroups, cGroupSeparator, bEraseTrailingDecZeros);
+}
+
+/** A wrapper around rtl_math_doubleToString that appends to an
+    rtl::OStringBuffer, with no grouping.
+
+    @since LibreOffice 5.4
+*/
+inline void doubleToStringBuffer(
+    rtl::OStringBuffer& rBuffer, double fValue, rtl_math_StringFormat eFormat,
+    sal_Int32 nDecPlaces, sal_Char cDecSeparator,
+    bool bEraseTrailingDecZeros = false)
+{
+    rtl_String ** pData;
+    sal_Int32 * pCapacity;
+    rBuffer.accessInternals(&pData, &pCapacity);
+    rtl_math_doubleToString(
+        pData, pCapacity, rBuffer.getLength(), fValue, eFormat, nDecPlaces,
+        cDecSeparator, NULL, 0, bEraseTrailingDecZeros);
+}
+
 /** A wrapper around rtl_math_doubleToUString.
  */
 inline rtl::OUString doubleToUString(double fValue,
diff --git a/include/rtl/strbuf.hxx b/include/rtl/strbuf.hxx
index 7cf4123d0ae8..791eb142f9dc 100644
--- a/include/rtl/strbuf.hxx
+++ b/include/rtl/strbuf.hxx
@@ -988,6 +988,30 @@ public:
         return *this;
     }
 
+    /** Allows access to the internal data of this OStringBuffer, for effective
+        manipulation.
+
+        This function should be used with care.  After you have called this
+        function, you may use the returned pInternalData and pInternalCapacity
+        only as long as you make no other calls on this OUStringBuffer.
+
+        @param pInternalData
+        This output parameter receives a pointer to the internal data
+        (rtl_String pointer).  pInternalData itself must not be null.
+
+        @param pInternalCapacity
+        This output parameter receives a pointer to the internal capacity.
+        pInternalCapacity itself must not be null.
+
+        @since LibreOffice 5.4
+    */
+    void accessInternals(
+        rtl_String *** pInternalData, sal_Int32 ** pInternalCapacity)
+    {
+        *pInternalData = &pData;
+        *pInternalCapacity = &nCapacity;
+    }
+
 private:
     /**
         A pointer to the data structure which contains the data.