3 files changed, 36 insertions, 40 deletions

diff --git a/core/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp b/core/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp
index 7c489a35dc..40ba362ad6 100644
--- a/core/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp
+++ b/core/fpdfapi/fpdf_parser/fpdf_parser_decode.cpp
@@ -532,45 +532,40 @@ CFX_ByteString PDF_EncodeString(const CFX_ByteString& src, FX_BOOL bHex) {
   result.AppendChar('(');
   for (int i = 0; i < srclen; i++) {
     uint8_t ch = src[i];
-    if (ch == ')' || ch == '\\' || ch == '(') {
-      result.AppendChar('\\');
-    } else if (ch == 0x0a) {
+    if (ch == 0x0a) {
       result << "\\n";
       continue;
-    } else if (ch == 0x0d) {
+    }
+    if (ch == 0x0d) {
       result << "\\r";
       continue;
     }
+    if (ch == ')' || ch == '\\' || ch == '(')
+      result.AppendChar('\\');
     result.AppendChar(ch);
   }
   result.AppendChar(')');
   return result.MakeString();
 }
 
-void FlateEncode(const uint8_t* src_buf,
+bool FlateEncode(const uint8_t* src_buf,
                  uint32_t src_size,
-                 uint8_t*& dest_buf,
-                 uint32_t& dest_size) {
+                 uint8_t** dest_buf,
+                 uint32_t* dest_size) {
   CCodec_ModuleMgr* pEncoders = CPDF_ModuleMgr::Get()->GetCodecModule();
-  if (pEncoders) {
-    pEncoders->GetFlateModule()->Encode(src_buf, src_size, dest_buf, dest_size);
-  }
+  return pEncoders &&
+         pEncoders->GetFlateModule()->Encode(src_buf, src_size, dest_buf,
+                                             dest_size);
 }
 
-void FlateEncode(const uint8_t* src_buf,
-                 uint32_t src_size,
-                 int predictor,
-                 int Colors,
-                 int BitsPerComponent,
-                 int Columns,
-                 uint8_t*& dest_buf,
-                 uint32_t& dest_size) {
+bool PngEncode(const uint8_t* src_buf,
+               uint32_t src_size,
+               uint8_t** dest_buf,
+               uint32_t* dest_size) {
   CCodec_ModuleMgr* pEncoders = CPDF_ModuleMgr::Get()->GetCodecModule();
-  if (pEncoders) {
-    pEncoders->GetFlateModule()->Encode(src_buf, src_size, predictor, Colors,
-                                        BitsPerComponent, Columns, dest_buf,
-                                        dest_size);
-  }
+  return pEncoders &&
+         pEncoders->GetFlateModule()->PngEncode(src_buf, src_size, dest_buf,
+                                                dest_size);
 }
 
 uint32_t FlateDecode(const uint8_t* src_buf,
diff --git a/core/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp b/core/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp
index 308c9f11c9..e9ca958411 100644
--- a/core/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp
+++ b/core/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp
@@ -38,14 +38,14 @@ TEST_F(FPDFParserDecodeEmbeddertest, FlateEncode) {
 
   for (size_t i = 0; i < FX_ArraySize(flate_encode_cases); ++i) {
     const pdfium::StrFuncTestData& data = flate_encode_cases[i];
-    unsigned char* result;
-    unsigned int result_size;
-    FlateEncode(data.input, data.input_size, result, result_size);
-    ASSERT_TRUE(result);
+    unsigned char* buf = nullptr;
+    unsigned int buf_size;
+    EXPECT_TRUE(FlateEncode(data.input, data.input_size, &buf, &buf_size));
+    ASSERT_TRUE(buf);
     EXPECT_EQ(std::string((const char*)data.expected, data.expected_size),
-              std::string((const char*)result, result_size))
+              std::string((const char*)buf, buf_size))
         << " for case " << i;
-    FX_Free(result);
+    FX_Free(buf);
   }
 }
 
diff --git a/core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h b/core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h
index 1f1095b396..5ae4011c76 100644
--- a/core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h
+++ b/core/fpdfapi/fpdf_parser/include/fpdf_parser_decode.h
@@ -24,18 +24,19 @@ CFX_WideString PDF_DecodeText(const CFX_ByteString& bstr);
 CFX_ByteString PDF_EncodeText(const FX_WCHAR* pString, int len = -1);
 CFX_ByteString PDF_EncodeText(const CFX_WideString& str);
 
-void FlateEncode(const uint8_t* src_buf,
+bool FlateEncode(const uint8_t* src_buf,
                  uint32_t src_size,
-                 uint8_t*& dest_buf,
-                 uint32_t& dest_size);
-void FlateEncode(const uint8_t* src_buf,
-                 uint32_t src_size,
-                 int predictor,
-                 int Colors,
-                 int BitsPerComponent,
-                 int Columns,
-                 uint8_t*& dest_buf,
-                 uint32_t& dest_size);
+                 uint8_t** dest_buf,
+                 uint32_t* dest_size);
+
+// This used to have more parameters like the predictor and bpc, but there was
+// only one caller, so the interface has been simplified, the values are hard
+// coded, and dead code has been removed.
+bool PngEncode(const uint8_t* src_buf,
+               uint32_t src_size,
+               uint8_t** dest_buf,
+               uint32_t* dest_size);
+
 uint32_t FlateDecode(const uint8_t* src_buf,
                      uint32_t src_size,
                      uint8_t*& dest_buf,