RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-27 07:37:46 +00:00
Code Issues Activity Actions

LibGfx: Use count_leading_zeroes to calculate nearest power of 2

Browse source 
This removes the possibility of an infinite loop.
This commit is contained in:
Tim Ledbetter 2023-10-25 21:52:26 +01:00 • committed by Andreas Kling
parent 6e4c97a328
commit 7096ea82f9
2 changed files with 6 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

7
Userland/Libraries/LibGfx/Font/WOFF/Font.cpp
View file

@ -63,10 +63,9 @@ static constexpr u32 WOFF_SIGNATURE = 0x774F4646;
static u16 pow_2_less_than_or_equal(u16 x) static u16 pow_2_less_than_or_equal(u16 x)
{ {
u16 result = 1; VERIFY(x > 0);
while (result < x) VERIFY(x < 32769);
result <<= 1; return 1 << (sizeof(u16) * 8 - count_leading_zeroes<u16>(x - 1));
return result;
} }
ErrorOr<NonnullRefPtr<Font>> Font::try_load_from_file(DeprecatedString path, unsigned int index) ErrorOr<NonnullRefPtr<Font>> Font::try_load_from_file(DeprecatedString path, unsigned int index)

7
Userland/Libraries/LibGfx/Font/WOFF2/Font.cpp
View file

@ -111,10 +111,9 @@ static i16 be_i16(u8 const* ptr)
static u16 pow_2_less_than_or_equal(u16 x) static u16 pow_2_less_than_or_equal(u16 x)
{ {
u16 result = 1; VERIFY(x > 0);
while (result < x) VERIFY(x < 32769);
result <<= 1; return 1 << (sizeof(u16) * 8 - count_leading_zeroes<u16>(x - 1));
return result;
} }
enum class TransformationVersion { enum class TransformationVersion {