Change the forced clear order of CPDF_DocPageData::Clear, and remove m_pDocument in CPDF_Color

If not forced clear, the counter of CPDF_Pattern will take care the count of referenced instance.
When forced clear, clear color first to make sure pattern still exists when referencing it.

BUG=411154
R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/554913003

3 files changed, 21 insertions, 20 deletions

diff --git a/core/include/fpdfapi/fpdf_resource.h b/core/include/fpdfapi/fpdf_resource.h
index 4ce4ddc8bb..25256fa86a 100644
--- a/core/include/fpdfapi/fpdf_resource.h
+++ b/core/include/fpdfapi/fpdf_resource.h
@@ -680,10 +680,8 @@ class CPDF_Color : public CFX_Object
 {
 public:
 
-    CPDF_Color()
+    CPDF_Color() :m_pCS(NULL), m_pBuffer(NULL)
     {
-        m_pBuffer = NULL;
-        m_pCS = NULL;
     }
 
     CPDF_Color(int family);
@@ -720,10 +718,10 @@ public:
 
     CPDF_ColorSpace*		m_pCS;
 
-    FX_FLOAT*			m_pBuffer;
 protected:
     void	ReleaseBuffer();
     void	ReleaseColorSpace();
+    FX_FLOAT*			    m_pBuffer;
 };
 #define PATTERN_TILING		1
 #define PATTERN_SHADING		2
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
index cf6dec51df..4f619da961 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_colors.cpp
@@ -1289,8 +1289,10 @@ void CPDF_Color::ReleaseBuffer()
         PatternValue* pvalue = (PatternValue*)m_pBuffer;
         CPDF_Pattern* pPattern = pvalue->m_pPattern;
         if (pPattern && pPattern->m_pDocument) {
-            pPattern->SaveColor(NULL);
-            pPattern->m_pDocument->GetPageData()->ReleasePattern(pPattern->m_pPatternObj);
+            CPDF_DocPageData *pPageData = pPattern->m_pDocument->GetPageData();
+            if (pPageData && !pPageData->IsForceClear()) {
+                pPageData->ReleasePattern(pPattern->m_pPatternObj);
+            }
         }
     }
     FX_Free(m_pBuffer);
@@ -1345,9 +1347,10 @@ void CPDF_Color::SetValue(CPDF_Pattern* pPattern, FX_FLOAT* comps, int ncomps)
     CPDF_DocPageData* pDocPageData = NULL;
     PatternValue* pvalue = (PatternValue*)m_pBuffer;
     if (pvalue->m_pPattern && pvalue->m_pPattern->m_pDocument) {
-        pDocPageData = pvalue->m_pPattern->m_pDocument->GetPageData();
-        pvalue->m_pPattern->SaveColor(NULL);
-        pDocPageData->ReleasePattern(pvalue->m_pPattern->m_pPatternObj);
+        CPDF_DocPageData *pDocPageData = pvalue->m_pPattern->m_pDocument->GetPageData();
+        if (pDocPageData && !pDocPageData->IsForceClear()) {
+            pDocPageData->ReleasePattern(pvalue->m_pPattern->m_pPatternObj);
+        }
     }
     pvalue->m_nComps = ncomps;
     pvalue->m_pPattern = pPattern;
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp
index 16f0a9cfad..131edbe9b5 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_doc.cpp
@@ -154,17 +154,6 @@ void CPDF_DocPageData::Clear(FX_BOOL bForceRelease)
     FX_DWORD	nCount;
 
     m_bForceClear = bForceRelease;
-    pos = m_PatternMap.GetStartPosition();
-    while (pos) {
-        CPDF_Object* ptObj;
-        CPDF_CountedObject<CPDF_Pattern*>* ptData;
-        m_PatternMap.GetNextAssoc(pos, ptObj, ptData);
-        nCount = ptData->m_nCount;
-        if (bForceRelease || nCount < 2) {
-            delete ptData->m_Obj;
-            ptData->m_Obj = NULL;
-        }
-    }
     pos = m_FontMap.GetStartPosition();
     while (pos) {
         CPDF_Dictionary* fontDict;
@@ -233,6 +222,17 @@ void CPDF_DocPageData::Clear(FX_BOOL bForceRelease)
             m_FontFileMap.RemoveKey(ftKey);
         }
     }
+    pos = m_PatternMap.GetStartPosition();
+    while (pos) {
+        CPDF_Object* ptObj;
+        CPDF_CountedObject<CPDF_Pattern*>* ptData;
+        m_PatternMap.GetNextAssoc(pos, ptObj, ptData);
+        nCount = ptData->m_nCount;
+        if (bForceRelease || nCount < 2) {
+            delete ptData->m_Obj;
+            ptData->m_Obj = NULL;
+        }
+    }
 }
 CPDF_Font* CPDF_DocPageData::GetFont(CPDF_Dictionary* pFontDict, FX_BOOL findOnly)
 {