Fix length field in dictionary on create stream

The CPDF_stream constructors were not setting the "Length" into the stream dictionary. 
The "Length" was being set by the SetData methods.
This CL fixes the constructor to properly set the "Length" field.

Change-Id: Iee1bd7f7a096d415ab01ee3d2f3416e19e87ece9
Reviewed-on: https://pdfium-review.googlesource.com/13010
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Art Snake <art-snake@yandex-team.ru>

4 files changed, 48 insertions, 16 deletions

diff --git a/core/fpdfapi/parser/cpdf_object_unittest.cpp b/core/fpdfapi/parser/cpdf_object_unittest.cpp
index dd170ba90e..169e0f1e56 100644
--- a/core/fpdfapi/parser/cpdf_object_unittest.cpp
+++ b/core/fpdfapi/parser/cpdf_object_unittest.cpp
@@ -828,6 +828,30 @@ TEST(PDFStreamTest, SetDataAndRemoveFilter) {
   EXPECT_FALSE(stream->GetDict()->KeyExist("DecodeParms"));
 }
 
+TEST(PDFStreamTest, LengthInDictionaryOnCreate) {
+  static constexpr uint32_t kBufSize = 100;
+  // The length field should be created on stream create.
+  {
+    std::unique_ptr<uint8_t, FxFreeDeleter> data;
+    data.reset(FX_Alloc(uint8_t, kBufSize));
+    auto stream = pdfium::MakeUnique<CPDF_Stream>(
+        std::move(data), kBufSize, pdfium::MakeUnique<CPDF_Dictionary>());
+    EXPECT_EQ(static_cast<int>(kBufSize),
+              stream->GetDict()->GetIntegerFor("Length"));
+  }
+  // The length field should be corrected on stream create.
+  {
+    std::unique_ptr<uint8_t, FxFreeDeleter> data;
+    data.reset(FX_Alloc(uint8_t, kBufSize));
+    auto dict = pdfium::MakeUnique<CPDF_Dictionary>();
+    dict->SetNewFor<CPDF_Number>("Length", 30000);
+    auto stream = pdfium::MakeUnique<CPDF_Stream>(std::move(data), kBufSize,
+                                                  std::move(dict));
+    EXPECT_EQ(static_cast<int>(kBufSize),
+              stream->GetDict()->GetIntegerFor("Length"));
+  }
+}
+
 TEST(PDFDictionaryTest, CloneDirectObject) {
   CPDF_IndirectObjectHolder objects_holder;
   auto dict = pdfium::MakeUnique<CPDF_Dictionary>();
diff --git a/core/fpdfapi/parser/cpdf_object_walker_unittest.cpp b/core/fpdfapi/parser/cpdf_object_walker_unittest.cpp
index 66c559d3ca..c5ffe844ad 100644
--- a/core/fpdfapi/parser/cpdf_object_walker_unittest.cpp
+++ b/core/fpdfapi/parser/cpdf_object_walker_unittest.cpp
@@ -38,6 +38,8 @@ std::string Walk(CPDF_Object* object) {
       result << " Stream";
     else if (obj->IsReference())
       result << " Ref";
+    else if (obj->IsNumber())
+      result << " Num";
     else if (obj->IsNull())
       result << " Null";
     else
@@ -72,13 +74,14 @@ TEST(CPDF_ObjectWalkerTest, CombinedObject) {
   array->Add(pdfium::MakeUnique<CPDF_Stream>(
       nullptr, 0, pdfium::MakeUnique<CPDF_Dictionary>()));
   dict->SetFor("3", std::move(array));
-  EXPECT_EQ(Walk(dict.get()), "Dict Str Bool Arr Ref Null Stream Dict");
+  // The last number for stream length.
+  EXPECT_EQ(Walk(dict.get()), "Dict Str Bool Arr Ref Null Stream Dict Num");
 }
 
 TEST(CPDF_ObjectWalkerTest, GetParent) {
-  auto level_4 = pdfium::MakeUnique<CPDF_Null>();
+  auto level_4 = pdfium::MakeUnique<CPDF_Number>(0);
   auto level_3 = pdfium::MakeUnique<CPDF_Dictionary>();
-  level_3->SetFor("AnyObj", std::move(level_4));
+  level_3->SetFor("Length", std::move(level_4));
   auto level_2 =
       pdfium::MakeUnique<CPDF_Stream>(nullptr, 0, std::move(level_3));
   auto level_1 = pdfium::MakeUnique<CPDF_Array>();
@@ -86,7 +89,7 @@ TEST(CPDF_ObjectWalkerTest, GetParent) {
   auto level_0 = pdfium::MakeUnique<CPDF_Dictionary>();
   level_0->SetFor("Array", std::move(level_1));
 
-  // We have <</Array [ stream( << /AnyObj null >>) ]>>
+  // We have <</Array [ stream( << /Length 0 >>) ]>>
   // In this case each step will increase depth.
   // And on each step the prev object should be parent for current.
   const CPDF_Object* cur_parent = nullptr;
diff --git a/core/fpdfapi/parser/cpdf_stream.cpp b/core/fpdfapi/parser/cpdf_stream.cpp
index 1c8660efb0..fadaec1b7e 100644
--- a/core/fpdfapi/parser/cpdf_stream.cpp
+++ b/core/fpdfapi/parser/cpdf_stream.cpp
@@ -22,7 +22,9 @@ CPDF_Stream::CPDF_Stream() {}
 CPDF_Stream::CPDF_Stream(std::unique_ptr<uint8_t, FxFreeDeleter> pData,
                          uint32_t size,
                          std::unique_ptr<CPDF_Dictionary> pDict)
-    : m_dwSize(size), m_pDict(std::move(pDict)), m_pDataBuf(std::move(pData)) {}
+    : m_pDict(std::move(pDict)) {
+  SetData(std::move(pData), size);
+}
 
 CPDF_Stream::~CPDF_Stream() {
   m_ObjNum = kInvalidObjNum;
@@ -54,14 +56,7 @@ void CPDF_Stream::InitStream(const uint8_t* pData,
                              uint32_t size,
                              std::unique_ptr<CPDF_Dictionary> pDict) {
   m_pDict = std::move(pDict);
-  m_bMemoryBased = true;
-  m_pFile = nullptr;
-  m_pDataBuf.reset(FX_Alloc(uint8_t, size));
-  if (pData)
-    memcpy(m_pDataBuf.get(), pData, size);
-  m_dwSize = size;
-  if (m_pDict)
-    m_pDict->SetNewFor<CPDF_Number>("Length", static_cast<int>(m_dwSize));
+  SetData(pData, size);
 }
 
 void CPDF_Stream::InitStreamFromFile(
@@ -110,10 +105,19 @@ void CPDF_Stream::SetDataAndRemoveFilter(std::ostringstream* stream) {
 }
 
 void CPDF_Stream::SetData(const uint8_t* pData, uint32_t size) {
+  std::unique_ptr<uint8_t, FxFreeDeleter> data_copy;
+  if (pData) {
+    data_copy.reset(FX_Alloc(uint8_t, size));
+    memcpy(data_copy.get(), pData, size);
+  }
+  SetData(std::move(data_copy), size);
+}
+
+void CPDF_Stream::SetData(std::unique_ptr<uint8_t, FxFreeDeleter> pData,
+                          uint32_t size) {
   m_bMemoryBased = true;
-  m_pDataBuf.reset(FX_Alloc(uint8_t, size));
-  if (pData)
-    memcpy(m_pDataBuf.get(), pData, size);
+  m_pFile = nullptr;
+  m_pDataBuf = std::move(pData);
   m_dwSize = size;
   if (!m_pDict)
     m_pDict = pdfium::MakeUnique<CPDF_Dictionary>();
diff --git a/core/fpdfapi/parser/cpdf_stream.h b/core/fpdfapi/parser/cpdf_stream.h
index 1dbbd0343e..3c3b674a48 100644
--- a/core/fpdfapi/parser/cpdf_stream.h
+++ b/core/fpdfapi/parser/cpdf_stream.h
@@ -41,6 +41,7 @@ class CPDF_Stream : public CPDF_Object {
 
   // Does not takes ownership of |pData|, copies into internally-owned buffer.
   void SetData(const uint8_t* pData, uint32_t size);
+  void SetData(std::unique_ptr<uint8_t, FxFreeDeleter> pData, uint32_t size);
   void SetData(std::ostringstream* stream);
   // Set data and remove "Filter" and "DecodeParms" fields from stream
   // dictionary.