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>
1. Define the transfer protocol revision mechanism. Increase the revision number to 0.2 and inform user to use the latest one when the HOST software is too old.
New HOST software will implement logic to handle all other revision mismatch cases.
2. Define new debug message packet to print the debug agent trace information by debug port channel.
3. Add check sum mechanism in the communication protocol between TARGET/HOST.
4. Introduced one "try" mechanism to avoid Debug Agent crashed by some invalid HOST command.
5. Enable the late-attach feature: Change the break in from "!" to "\xFC". Add a new short symbol "\xFA" for attach and a new debug command for detach.
6. Support Terminal work on debug port by install EFI Serial IO protocol upon Debug Communication Library.
7. Enable CPUID feature.
8. Enable the hardware data breakpoint.
9. add handshake to improve usb debug cable identify stability issue.
10.Refine all the communication protocol packet to improve extensibility and debugging performance.
a. Use 64bit for IO port address.
b. Add additional Width field to READ_MEMORY/WRITE_MEMORY.
c. Add SEARCH_SIGNATURE support to speed the symbol finding for late attach.
d. Remove READ_GROUP register.
e. Add READ_ALL_REGISTERS support (WinDbg always requests to read all registers).
11.Move AcquireDebugPortControl () in advance to fix resource collision on IpiSentByApFlag.
12.Fix IO break point does not work issue in PEI phase.
13.Avoid BSP/APs collision when they met break point at the same time.
14.Solve a bug of calculating debug handle in sec phase.
15.Use mailbox content at Dxe phase but not clear it and reinitialize again.
16.Fix FP/MMX/XMM/IO/MSR access issue in both Gdb and WinDbg.
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Signed-off-by: Feng Tian <feng.tian@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13437 6f19259b-4bc3-4df7-8a09-765794883524
Michael Kubackiandmergify[bot]
Antoine Coeurandmergify[bot]
Michael D Kinney
vanjeff