Replace traditional `#ifndef`/`#define`/`#endif` include guards with
`#pragma` once.
`#pragma once` is a widely supported preprocessor directive that
prevents header files from being included multiple times. It is
supported by all toolchains used to build edk2: GCC, Clang/LLVM, and
MSVC.
Compared to macro-based include guards, `#pragma once`:
- Eliminates the risk of macro name collisions or copy/paste errors
where two headers inadvertently use the same guard macro.
- Eliminate inconsistency in the way include guard macros are named
(e.g., some files use `__FILE_H__`, others use `FILE_H_`, etc.).
- Reduces boilerplate (three lines replaced by one).
- Avoids polluting the macro namespace with guard symbols.
- Can improve build times as the preprocessor can skip re-opening the
file entirely, rather than re-reading it to find the matching
`#endif` ("multiple-include optimization").
- Note that some compilers may already optimize traditional include
guards, by recognzining the idiomatic pattern.
This change is made acknowledging that overall portability of the
code will technically be reduced, as `#pragma once` is not part of the
C/C++ standards.
However, this is considered acceptable given:
1. edk2 already defines a subset of supported compilers in
BaseTools/Conf/tools_def.template, all of which have supported
`#pragma once` for over two decades.
2. There have been concerns raised to the project about inconsistent
include guard naming and potential macro collisions.
Approximate compiler support dates:
- MSVC: Supported since Visual C++ 4.2 (1996)
- GCC: Supported since 3.4 (2004)
(http://gnu.ist.utl.pt/software/gcc/gcc-3.4/changes.html)
- Clang (LLVM based): Since initial release in 2007
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
This reverts commit 58766a4729.
In edk2 commit 58766a4, validation of the two reserved FAT entries
was added.
However, it also checked the return of FatGetFatEntry to MAX_UINT32,
which is what FatGetFatEntry returns when it encounters an error,
e.g. not being able to read the disk. However, MAX_UINT32 is also a
valid value for the reserved FAT entries and under some conditions
these will be returned in the success case.
A FAT volume formatted with these valid values of the reserved FAT
entries will fail to boot an OS because the opening of the volume
will fail.
However, the reason FatGetFatEntry returns MAX_UINT32 is that most
other uses of the function are comparing it against the END_OF_CHAIN
mark, which MAX_UINT32 will trip and those functions will fail out.
Because this is a critical bug that can prevent OS booting and the
bug the original commit was solving was accounting for a bad FAT
filesystem formatting tool, this commit is reverted for now.
Future work will clean up FatGetFatEntry so that it returns an
EFI_STATUS, but that involves more work and this bug needs to be
resolved in the meantime.
Signed-off-by: Oliver Smith-Denny <osde@microsoft.com>
There are two reserved FAT entries in the FAT filesystem that
are expected to have valid contents in them. Today the FAT drivers
do not validate these entries when reading from a device for the
first time. This can cause infinite loops in the FAT driver when
trying to read corrupted disks as reported in
https://github.com/tianocore/edk2/issues/9679.
This PR follows the recommended update requested in that bug to
check the two reserved FAT entries and validate their contents
against the spec defined values in both FatPei and EnhancedFatDxe
when opening a device for the first time.
Signed-off-by: Oliver Smith-Denny <osde@microsoft.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3737
Apply uncrustify changes to .c/.h files in the FatPkg package
Cc: Andrew Fish <afish@apple.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
In FatPkg, cluster-related varibles are declared as unsigned type (e.g.
UINT32/UINTN). To keep the comparisions involving those variables
type-matched, declare the definition FAT_CLUSTER_SPECIAL as unsigned type
explicitly.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
(based on FatPkg commit 171c4de5919a4638db8f6f472b365ffbbac6070b)
[jordan.l.justen@intel.com: Use script to relicense to 2-clause BSD]
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Acked-by: Mark Doran <mark.doran@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
(based on FatPkg commit e51cd032db84a6fb1f44a0605f80d96f5fdf4bc6)
[jordan.l.justen@intel.com: Use script to relicense to 2-clause BSD]
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Acked-by: Mark Doran <mark.doran@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
