Add test for CPDF_SyntaxParser::ReadHexString.

This CL adds tests for the ReadHexString method of the syntax parser.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1433503002 .

4 files changed, 176 insertions, 2 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 511065d3cd..53d234a94d 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -718,6 +718,7 @@ test("pdfium_unittests") {
     "core/src/fpdfapi/fpdf_font/fpdf_font_unittest.cpp",
     "core/src/fpdfapi/fpdf_page/fpdf_page_parser_old_unittest.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_decode_unittest.cpp",
+    "core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp",
     "core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp",
     "core/src/fxcrt/fx_basic_bstring_unittest.cpp",
     "core/src/fxcrt/fx_basic_memmgr_unittest.cpp",
diff --git a/core/include/fpdfapi/fpdf_parser.h b/core/include/fpdfapi/fpdf_parser.h
index 6fec26d687..b7684e530a 100644
--- a/core/include/fpdfapi/fpdf_parser.h
+++ b/core/include/fpdfapi/fpdf_parser.h
@@ -299,6 +299,10 @@ class CPDF_SyntaxParser {
   CFX_ByteString GetNextWord(FX_BOOL& bIsNumber);
 
  protected:
+  friend class CPDF_Parser;
+  friend class CPDF_DataAvail;
+  friend class fpdf_parser_parser_ReadHexString_Test;
+
   static const int kParserMaxRecursionDepth = 64;
   static int s_CurrentRecursionDepth;
 
@@ -352,8 +356,6 @@ class CPDF_SyntaxParser {
   FX_BOOL m_bIsNumber;
 
   FX_FILESIZE m_dwWordPos;
-  friend class CPDF_Parser;
-  friend class CPDF_DataAvail;
 };
 
 #define PDFPARSE_TYPEONLY 1
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp
new file mode 100644
index 0000000000..8063d6fd9c
--- /dev/null
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp
@@ -0,0 +1,170 @@
+// Copyright 2015 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+#include "../../../include/fpdfapi/fpdf_parser.h"
+
+// TODO(thestig) Using unique_ptr with ReleaseDeleter is still not ideal.
+// Come up or wait for something better.
+using ScopedFileStream =
+    nonstd::unique_ptr<IFX_FileStream, ReleaseDeleter<IFX_FileStream>>;
+
+TEST(fpdf_parser_parser, ReadHexString) {
+  {
+    // Empty string.
+    uint8_t data[] = "";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 0, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("", parser.ReadHexString());
+    EXPECT_EQ(0, parser.SavePos());
+  }
+
+  {
+    // Blank string.
+    uint8_t data[] = "  ";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 2, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("", parser.ReadHexString());
+    EXPECT_EQ(2, parser.SavePos());
+  }
+
+  {
+    // Skips unknown characters.
+    uint8_t data[] = "z12b";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 4, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x12\xb0", parser.ReadHexString());
+    EXPECT_EQ(4, parser.SavePos());
+  }
+
+  {
+    // Skips unknown characters.
+    uint8_t data[] = "*<&*#$^&@1";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 10, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x10", parser.ReadHexString());
+    EXPECT_EQ(10, parser.SavePos());
+  }
+
+  {
+    // Skips unknown characters.
+    uint8_t data[] = "\x80zab";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 4, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\xab", parser.ReadHexString());
+    EXPECT_EQ(4, parser.SavePos());
+  }
+
+  {
+    // Skips unknown characters.
+    uint8_t data[] = "\xffzab";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 4, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\xab", parser.ReadHexString());
+    EXPECT_EQ(4, parser.SavePos());
+  }
+
+  {
+    // Regular conversion.
+    uint8_t data[] = "1A2b>abcd";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 9, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x1a\x2b", parser.ReadHexString());
+    EXPECT_EQ(5, parser.SavePos());
+  }
+
+  {
+    // Position out of bounds.
+    uint8_t data[] = "12ab>";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 5, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    parser.RestorePos(5);
+    EXPECT_EQ("", parser.ReadHexString());
+
+    parser.RestorePos(6);
+    EXPECT_EQ("", parser.ReadHexString());
+
+    parser.RestorePos(-1);
+    EXPECT_EQ("", parser.ReadHexString());
+
+    parser.RestorePos(0xfffffffffff);
+    EXPECT_EQ("", parser.ReadHexString());
+
+    // Check string still parses when set to 0.
+    parser.RestorePos(0);
+    EXPECT_EQ("\x12\xab", parser.ReadHexString());
+  }
+
+  {
+    // Missing ending >.
+    uint8_t data[] = "1A2b";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 4, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x1a\x2b", parser.ReadHexString());
+    EXPECT_EQ(4, parser.SavePos());
+  }
+
+  {
+    // Missing ending >.
+    uint8_t data[] = "12abz";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 5, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x12\xab", parser.ReadHexString());
+    EXPECT_EQ(5, parser.SavePos());
+  }
+
+  {
+    // Uneven number of bytes.
+    uint8_t data[] = "1A2>asdf";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 8, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x1a\x20", parser.ReadHexString());
+    EXPECT_EQ(4, parser.SavePos());
+  }
+
+  {
+    // Uneven number of bytes.
+    uint8_t data[] = "1A2zasdf";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 8, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("\x1a\x2a\xdf", parser.ReadHexString());
+    EXPECT_EQ(8, parser.SavePos());
+  }
+
+  {
+    // Just ending character.
+    uint8_t data[] = ">";
+    ScopedFileStream stream(FX_CreateMemoryStream(data, 1, FALSE));
+
+    CPDF_SyntaxParser parser;
+    parser.InitParser(stream.get(), 0);
+    EXPECT_EQ("", parser.ReadHexString());
+    EXPECT_EQ(1, parser.SavePos());
+  }
+}
diff --git a/pdfium.gyp b/pdfium.gyp
index 8687e76cac..1afadaa672 100644
--- a/pdfium.gyp
+++ b/pdfium.gyp
@@ -718,6 +718,7 @@
         'core/src/fpdfapi/fpdf_font/fpdf_font_unittest.cpp',
         'core/src/fpdfapi/fpdf_page/fpdf_page_parser_old_unittest.cpp',
         'core/src/fpdfapi/fpdf_parser/fpdf_parser_decode_unittest.cpp',
+        'core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_unittest.cpp',
         'core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp',
         'core/src/fxcrt/fx_basic_bstring_unittest.cpp',
         'core/src/fxcrt/fx_basic_memmgr_unittest.cpp',