Merge GetBits32() impls into one. Put it in fxcrt.

Review-Url: https://codereview.chromium.org/1990153003

7 files changed, 46 insertions, 59 deletions

diff --git a/BUILD.gn b/BUILD.gn
index dbd827a7af..1dbfea9997 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1622,6 +1622,7 @@ test("pdfium_unittests") {
     "core/fxcrt/fx_basic_bstring_unittest.cpp",
     "core/fxcrt/fx_basic_gcc_unittest.cpp",
     "core/fxcrt/fx_basic_memmgr_unittest.cpp",
+    "core/fxcrt/fx_basic_util_unittest.cpp",
     "core/fxcrt/fx_basic_wstring_unittest.cpp",
     "core/fxcrt/fx_bidi_unittest.cpp",
     "core/fxcrt/fx_extension_unittest.cpp",
diff --git a/core/fpdfapi/fpdf_page/fpdf_page_func.cpp b/core/fpdfapi/fpdf_page/fpdf_page_func.cpp
index c9b0ea236e..bb1d631576 100644
--- a/core/fpdfapi/fpdf_page/fpdf_page_func.cpp
+++ b/core/fpdfapi/fpdf_page/fpdf_page_func.cpp
@@ -8,6 +8,7 @@
 
 #include <limits.h>
 
+#include <algorithm>
 #include <memory>
 #include <utility>
 #include <vector>
@@ -504,15 +505,6 @@ FX_FLOAT PDF_Interpolate(FX_FLOAT x,
   return ymin + (divisor ? (x - xmin) * (ymax - ymin) / divisor : 0);
 }
 
-uint32_t GetBits32(const uint8_t* pData, int bitpos, int nbits) {
-  int result = 0;
-  for (int i = 0; i < nbits; i++) {
-    if (pData[(bitpos + i) / 8] & (1 << (7 - (bitpos + i) % 8)))
-      result |= 1 << (nbits - i - 1);
-  }
-  return result;
-}
-
 class CPDF_PSFunc : public CPDF_Function {
  public:
   CPDF_PSFunc() : CPDF_Function(Type::kType4PostScript) {}
diff --git a/core/fxcrt/fx_basic_util.cpp b/core/fxcrt/fx_basic_util.cpp
index aa36d56f38..2d3483e9b3 100644
--- a/core/fxcrt/fx_basic_util.cpp
+++ b/core/fxcrt/fx_basic_util.cpp
@@ -7,8 +7,6 @@
 #include "core/fxcrt/include/fx_basic.h"
 #include "core/fxcrt/include/fx_ext.h"
 
-#include <cctype>
-
 #if _FXM_PLATFORM_ != _FXM_PLATFORM_WINDOWS_
 #include <dirent.h>
 #include <sys/types.h>
@@ -16,6 +14,9 @@
 #include <direct.h>
 #endif
 
+#include <algorithm>
+#include <cctype>
+
 CFX_PrivateData::CFX_PrivateData() {}
 
 CFX_PrivateData::~CFX_PrivateData() {
@@ -364,3 +365,33 @@ CFX_Vector_3by1 CFX_Matrix_3by3::TransformVector(const CFX_Vector_3by1& v) {
                          d * v.a + e * v.b + f * v.c,
                          g * v.a + h * v.b + i * v.c);
 }
+
+uint32_t GetBits32(const uint8_t* pData, int bitpos, int nbits) {
+  ASSERT(0 < nbits && nbits <= 32);
+  const uint8_t* dataPtr = &pData[bitpos / 8];
+  int bitShift;
+  int bitMask;
+  int dstShift;
+  int bitCount = bitpos & 0x07;
+  if (nbits < 8 && nbits + bitCount <= 8) {
+    bitShift = 8 - nbits - bitCount;
+    bitMask = (1 << nbits) - 1;
+    dstShift = 0;
+  } else {
+    bitShift = 0;
+    int bitOffset = 8 - bitCount;
+    bitMask = (1 << std::min(bitOffset, nbits)) - 1;
+    dstShift = nbits - bitOffset;
+  }
+  uint32_t result = (uint32_t)(*dataPtr++ >> bitShift & bitMask) << dstShift;
+  while (dstShift >= 8) {
+    dstShift -= 8;
+    result |= *dataPtr++ << dstShift;
+  }
+  if (dstShift > 0) {
+    bitShift = 8 - dstShift;
+    bitMask = (1 << dstShift) - 1;
+    result |= *dataPtr++ >> bitShift & bitMask;
+  }
+  return result;
+}
diff --git a/core/fxge/skia/fx_skia_device_unittest.cpp b/core/fxcrt/fx_basic_util_unittest.cpp
index 57a4ec140b..3272eab70c 100644
--- a/core/fxge/skia/fx_skia_device_unittest.cpp
+++ b/core/fxcrt/fx_basic_util_unittest.cpp
@@ -2,18 +2,18 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "core/fxge/skia/fx_skia_device.cpp"
+#include "core/fxcrt/include/fx_basic.h"
 #include "testing/fx_string_testhelpers.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
-uint32_t _GetBits32(const uint8_t* pData, int bitpos, int nbits) {
+uint32_t ReferenceGetBits32(const uint8_t* pData, int bitpos, int nbits) {
   int result = 0;
-  for (int i = 0; i < nbits; i++)
-    if (pData[(bitpos + i) / 8] & (1 << (7 - (bitpos + i) % 8))) {
+  for (int i = 0; i < nbits; i++) {
+    if (pData[(bitpos + i) / 8] & (1 << (7 - (bitpos + i) % 8)))
       result |= 1 << (nbits - i - 1);
-    }
+  }
   return result;
 }
 
@@ -23,9 +23,8 @@ TEST(fxge, GetBits32) {
   unsigned char data[] = {0xDE, 0x3F, 0xB1, 0x7C, 0x12, 0x9A, 0x04, 0x56};
   for (int nbits = 1; nbits <= 32; ++nbits) {
     for (int bitpos = 0; bitpos < (int)sizeof(data) * 8 - nbits; ++bitpos) {
-      uint32_t ref = _GetBits32(data, bitpos, nbits);
-      uint32_t test = GetBits32(data, bitpos, nbits);
-      EXPECT_TRUE(ref == test);
+      EXPECT_EQ(ReferenceGetBits32(data, bitpos, nbits),
+                GetBits32(data, bitpos, nbits));
     }
   }
 }
diff --git a/core/fxcrt/include/fx_basic.h b/core/fxcrt/include/fx_basic.h
index 7fdfbf699d..d3dce8c749 100644
--- a/core/fxcrt/include/fx_basic.h
+++ b/core/fxcrt/include/fx_basic.h
@@ -178,7 +178,7 @@ class CFX_UTF8Encoder {
 
 class CFX_BasicArray {
  protected:
-  CFX_BasicArray(int unit_size);
+  explicit CFX_BasicArray(int unit_size);
   CFX_BasicArray(const CFX_BasicArray&) = delete;
   ~CFX_BasicArray();
 
@@ -972,4 +972,6 @@ class CFX_Matrix_3by3 {
   FX_FLOAT i;
 };
 
+uint32_t GetBits32(const uint8_t* pData, int bitpos, int nbits);
+
 #endif  // CORE_FXCRT_INCLUDE_FX_BASIC_H_
diff --git a/core/fxge/skia/fx_skia_device.cpp b/core/fxge/skia/fx_skia_device.cpp
index 3168e2251b..177f10c5b9 100644
--- a/core/fxge/skia/fx_skia_device.cpp
+++ b/core/fxge/skia/fx_skia_device.cpp
@@ -174,36 +174,6 @@ bool AddColors(const CPDF_ExpIntFunc* pFunc, SkTDArray<SkColor>* skColors) {
   return true;
 }
 
-uint32_t GetBits32(const uint8_t* pData, int bitpos, int nbits) {
-  ASSERT(0 < nbits && nbits <= 32);
-  const uint8_t* dataPtr = &pData[bitpos / 8];
-  int bitShift;
-  int bitMask;
-  int dstShift;
-  int bitCount = bitpos & 0x07;
-  if (nbits < 8 && nbits + bitCount <= 8) {
-    bitShift = 8 - nbits - bitCount;
-    bitMask = (1 << nbits) - 1;
-    dstShift = 0;
-  } else {
-    bitShift = 0;
-    int bitOffset = 8 - bitCount;
-    bitMask = (1 << SkTMin(bitOffset, nbits)) - 1;
-    dstShift = nbits - bitOffset;
-  }
-  uint32_t result = (uint32_t)(*dataPtr++ >> bitShift & bitMask) << dstShift;
-  while (dstShift >= 8) {
-    dstShift -= 8;
-    result |= *dataPtr++ << dstShift;
-  }
-  if (dstShift > 0) {
-    bitShift = 8 - dstShift;
-    bitMask = (1 << dstShift) - 1;
-    result |= *dataPtr++ >> bitShift & bitMask;
-  }
-  return result;
-}
-
 uint8_t FloatToByte(FX_FLOAT f) {
   ASSERT(0 <= f && f <= 1);
   return (uint8_t)(f * 255.99f);
diff --git a/pdfium.gyp b/pdfium.gyp
index 2f0392adc9..69f6908ccf 100644
--- a/pdfium.gyp
+++ b/pdfium.gyp
@@ -932,6 +932,7 @@
         'core/fxcrt/fx_basic_bstring_unittest.cpp',
         'core/fxcrt/fx_basic_gcc_unittest.cpp',
         'core/fxcrt/fx_basic_memmgr_unittest.cpp',
+        'core/fxcrt/fx_basic_util_unittest.cpp',
         'core/fxcrt/fx_basic_wstring_unittest.cpp',
         'core/fxcrt/fx_bidi_unittest.cpp',
         'core/fxcrt/fx_extension_unittest.cpp',
@@ -959,15 +960,6 @@
             'fpdfsdk/javascript/public_methods_unittest.cpp',
           ],
         }],
-        ['pdf_use_skia==1', {
-          'defines': ['PDF_ENABLE_SKIA'],
-          'dependencies': [
-            '<(DEPTH)/skia/skia.gyp:skia',
-          ],
-          'sources': [
-            'core/fxge/skia/fx_skia_device_unittest.cpp',
-          ],
-        }],
       ],
     },
     {