Refactor some code in CPDF_TextPage::ProcessTextObject().

Fix a memory leak while we are at it.

R=bo_xu@foxitsoftware.com

Review URL: https://codereview.chromium.org/813153002

2 files changed, 70 insertions, 55 deletions

diff --git a/core/src/fpdftext/fpdf_text_int.cpp b/core/src/fpdftext/fpdf_text_int.cpp
index 4650272e4c..c9cfbdda2d 100644
--- a/core/src/fpdftext/fpdf_text_int.cpp
+++ b/core/src/fpdftext/fpdf_text_int.cpp
@@ -1690,49 +1690,9 @@ void CPDF_TextPage::ProcessTextObject(PDFTEXT_Obj Obj)
     int nItems = pTextObj->CountItems();
     FX_FLOAT baseSpace = _CalculateBaseSpace(pTextObj, matrix);
 
-    FX_BOOL bIsBidiAndMirrosInverse = FALSE;
-    IFX_BidiChar* BidiChar = IFX_BidiChar::Create();
-    FX_INT32 nR2L = 0;
-    FX_INT32 nL2R = 0;
-    FX_INT32 start = 0, count = 0;
-    CPDF_TextObjectItem item;
-    for (FX_INT32 i = 0; i < nItems; i++) {
-        pTextObj->GetItemInfo(i, &item);
-        if (item.m_CharCode == (FX_DWORD)-1) {
-            continue;
-        }
-        CFX_WideString wstrItem = pFont->UnicodeFromCharCode(item.m_CharCode);
-        FX_WCHAR wChar = wstrItem.GetAt(0);
-        if ((wstrItem.IsEmpty() || wChar == 0) && item.m_CharCode) {
-            wChar = (FX_WCHAR)item.m_CharCode;
-        }
-        if (!wChar) {
-            continue;
-        }
-        if (BidiChar && BidiChar->AppendChar(wChar)) {
-            FX_INT32 ret = BidiChar->GetBidiInfo(start, count);
-            if (ret == 2) {
-                nR2L++;
-            }
-            else if (ret == 1) {
-                nL2R++;
-            }
-        }
-    }
-    if (BidiChar && BidiChar->EndChar()) {
-        FX_INT32 ret = BidiChar->GetBidiInfo(start, count);
-        if (ret == 2) {
-            nR2L++;
-        }
-        else if (ret == 1) {
-            nL2R++;
-        }
-    }
-    FX_BOOL bR2L = FALSE;
-    if (nR2L > 0 && nR2L >= nL2R) {
-        bR2L = TRUE;
-    }
-    bIsBidiAndMirrosInverse = bR2L && (matrix.a * matrix.d - matrix.b * matrix.c) < 0;
+    const FX_BOOL bR2L = IsRightToLeft(pTextObj, pFont, nItems);
+    const FX_BOOL bIsBidiAndMirrorInverse =
+        bR2L && (matrix.a * matrix.d - matrix.b * matrix.c) < 0;
     FX_INT32 iBufStartAppend = m_TempTextBuf.GetLength();
     FX_INT32 iCharListStartAppend = m_TempCharList.GetSize();
 
@@ -1877,21 +1837,71 @@ void CPDF_TextPage::ProcessTextObject(PDFTEXT_Obj Obj)
             }
         }
     }
-    if (bIsBidiAndMirrosInverse) {
-        FX_INT32 i, j;
-        i = iCharListStartAppend;
-        j = m_TempCharList.GetSize() - 1;
-        for (; i < j; i++, j--) {
-            std::swap(m_TempCharList[i], m_TempCharList[j]);
-            std::swap(m_TempCharList[i].m_Index, m_TempCharList[j].m_Index);
+    if (bIsBidiAndMirrorInverse) {
+        SwapTempTextBuf(iCharListStartAppend, iBufStartAppend);
+    }
+}
+void CPDF_TextPage::SwapTempTextBuf(FX_INT32 iCharListStartAppend,
+                                    FX_INT32 iBufStartAppend)
+{
+    FX_INT32 i, j;
+    i = iCharListStartAppend;
+    j = m_TempCharList.GetSize() - 1;
+    for (; i < j; i++, j--) {
+        std::swap(m_TempCharList[i], m_TempCharList[j]);
+        std::swap(m_TempCharList[i].m_Index, m_TempCharList[j].m_Index);
+    }
+    FX_WCHAR * pTempBuffer = m_TempTextBuf.GetBuffer();
+    i = iBufStartAppend;
+    j = m_TempTextBuf.GetLength() - 1;
+    for (; i < j; i++, j--) {
+        std::swap(pTempBuffer[i], pTempBuffer[j]);
+    }
+}
+FX_BOOL CPDF_TextPage::IsRightToLeft(const CPDF_TextObject* pTextObj,
+                                     const CPDF_Font* pFont,
+                                     int nItems) const
+{
+    IFX_BidiChar* BidiChar = IFX_BidiChar::Create();
+    FX_INT32 nR2L = 0;
+    FX_INT32 nL2R = 0;
+    FX_INT32 start = 0, count = 0;
+    CPDF_TextObjectItem item;
+    for (FX_INT32 i = 0; i < nItems; i++) {
+        pTextObj->GetItemInfo(i, &item);
+        if (item.m_CharCode == (FX_DWORD)-1) {
+            continue;
+        }
+        CFX_WideString wstrItem = pFont->UnicodeFromCharCode(item.m_CharCode);
+        FX_WCHAR wChar = wstrItem.GetAt(0);
+        if ((wstrItem.IsEmpty() || wChar == 0) && item.m_CharCode) {
+            wChar = (FX_WCHAR)item.m_CharCode;
         }
-        FX_WCHAR * pTempBuffer = m_TempTextBuf.GetBuffer();
-        i = iBufStartAppend;
-        j = m_TempTextBuf.GetLength() - 1;
-        for (; i < j; i++, j--) {
-            std::swap(pTempBuffer[i], pTempBuffer[j]);
+        if (!wChar) {
+            continue;
+        }
+        if (BidiChar && BidiChar->AppendChar(wChar)) {
+            FX_INT32 ret = BidiChar->GetBidiInfo(start, count);
+            if (ret == 2) {
+                nR2L++;
+            }
+            else if (ret == 1) {
+                nL2R++;
+            }
+        }
+    }
+    if (BidiChar && BidiChar->EndChar()) {
+        FX_INT32 ret = BidiChar->GetBidiInfo(start, count);
+        if (ret == 2) {
+            nR2L++;
+        }
+        else if (ret == 1) {
+            nL2R++;
         }
     }
+    if (BidiChar)
+      BidiChar->Release();
+    return (nR2L > 0 && nR2L >= nL2R);
 }
 FX_INT32 CPDF_TextPage::GetTextObjectWritingMode(const CPDF_TextObject* pTextObj)
 {
diff --git a/core/src/fpdftext/text_int.h b/core/src/fpdftext/text_int.h
index 65ffddea0a..c3f3b7108e 100644
--- a/core/src/fpdftext/text_int.h
+++ b/core/src/fpdftext/text_int.h
@@ -115,6 +115,11 @@ private:
     void		AddCharInfoByRLDirection(CFX_WideString& str, int i);
     FX_INT32	GetTextObjectWritingMode(const CPDF_TextObject* pTextObj);
     FX_INT32	FindTextlineFlowDirection();
+    void SwapTempTextBuf(FX_INT32 iCharListStartAppend,
+                         FX_INT32 iBufStartAppend);
+    FX_BOOL IsRightToLeft(const CPDF_TextObject* pTextObj,
+                          const CPDF_Font* pFont,
+                          int nItems) const;
 protected:
     CPDFText_ParseOptions			m_ParseOptions;
     CFX_WordArray					m_CharIndex;