Revert 261972 "Revert 261817 "cc: Remove all usage of GetArea() ..."

r261817 falsely accused! Reverting the revert, sorry for the noise.

> Revert 261817 "cc: Remove all usage of GetArea() from production..."
> 
> Suspected of causing failures on Linux CrOS ASan LSan:
> 
> http://build.chromium.org/p/chromium.memory/builders/Linux%20Chromium%20OS%20ASan%2BLSan%20Tests%20%283%29/builds/702
> 
> http://build.chromium.org/p/chromium.memory/builders/Linux%20Chromium%20OS%20ASan%2BLSan%20Tests%20%282%29/builds/664
> 
> http://build.chromium.org/p/chromium.memory/builders/Linux%20Chromium%20OS%20ASan%2BLSan%20Tests%20%281%29/builds/702
> 
> 
> > cc: Remove all usage of GetArea() from production code in cc
> > 
> > Consolidate the calls to turn gfx::Size into a number of bytes onto
> > the cc::SharedBitmap class. The class offers the following methods:
> > 1. Get a size_t bytes and bool saying if you overflowed or not.
> > 2. Get a size_t bytes and crash if you overflow.
> > 3. Get a size_t bytes and don't check for overflow.
> > 4. Tell me if the gfx::Size would overflow to create the size_t bytes.
> > 
> > These were the use cases I found in the existing code, plus the
> > addition of case 2. A few places that were finding the size_t bytes
> > without looking for overflow (case 3), from a previously-unchecked
> > gfx::Size, were changed to crash on overflow instead (case 2).
> > 
> > R=jbauman@chromium.org, piman@chromium.org
> > BUG=348332
> > 
> > Review URL: https://codereview.chromium.org/221523003
> 
> TBR=danakj@chromium.org
> 
> Review URL: https://codereview.chromium.org/226693005

TBR=scottmg@chromium.org, danakj@chromium.org

Review URL: https://codereview.chromium.org/226693007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262022 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 34 insertions, 6 deletions

diff --git a/cc/resources/shared_bitmap.cc b/cc/resources/shared_bitmap.cc
index 3b94d45..6d2ff0a 100644
--- a/cc/resources/shared_bitmap.cc
+++ b/cc/resources/shared_bitmap.cc
@@ -4,6 +4,7 @@
 
 #include "cc/resources/shared_bitmap.h"
 
+#include "base/logging.h"
 #include "base/numerics/safe_math.h"
 #include "base/rand_util.h"
 
@@ -12,19 +13,18 @@ namespace cc {
 SharedBitmap::SharedBitmap(
     base::SharedMemory* memory,
     const SharedBitmapId& id,
-    const base::Callback<void(SharedBitmap*)>& free_callback)
+    const base::Callback<void(SharedBitmap* bitmap)>& free_callback)
     : memory_(memory), id_(id), free_callback_(free_callback) {}
 
 SharedBitmap::~SharedBitmap() { free_callback_.Run(this); }
 
 // static
-bool SharedBitmap::GetSizeInBytes(const gfx::Size& size,
-                                  size_t* size_in_bytes) {
-  if (size.width() <= 0 || size.height() <= 0)
+bool SharedBitmap::SizeInBytes(const gfx::Size& size, size_t* size_in_bytes) {
+  if (size.IsEmpty())
     return false;
-  base::CheckedNumeric<int> s = size.width();
+  base::CheckedNumeric<size_t> s = 4;
+  s *= size.width();
   s *= size.height();
-  s *= 4;
   if (!s.IsValid())
     return false;
   *size_in_bytes = s.ValueOrDie();
@@ -32,6 +32,34 @@ bool SharedBitmap::GetSizeInBytes(const gfx::Size& size,
 }
 
 // static
+size_t SharedBitmap::CheckedSizeInBytes(const gfx::Size& size) {
+  CHECK(!size.IsEmpty());
+  base::CheckedNumeric<size_t> s = 4;
+  s *= size.width();
+  s *= size.height();
+  return s.ValueOrDie();
+}
+
+// static
+size_t SharedBitmap::UncheckedSizeInBytes(const gfx::Size& size) {
+  DCHECK(VerifySizeInBytes(size));
+  size_t s = 4;
+  s *= size.width();
+  s *= size.height();
+  return s;
+}
+
+// static
+bool SharedBitmap::VerifySizeInBytes(const gfx::Size& size) {
+  if (size.IsEmpty())
+    return false;
+  base::CheckedNumeric<size_t> s = 4;
+  s *= size.width();
+  s *= size.height();
+  return s.IsValid();
+}
+
+// static
 SharedBitmapId SharedBitmap::GenerateId() {
   SharedBitmapId id;
   // Needs cryptographically-secure random numbers.