Hi UEFI community,

I’d like to introduce the CdePkg to edk2-staging.

Some time ago I decided to write my own ANSI C Library for UEFI Shell and POST.

The UEFI Shell library (“Torito C Library”) has been production-ready for more than one year.

The POST version of the library (“CdeLib”) is not yet fully tested.

I will be demonstrating my verification procedure in the upcoming weeks on EDK2 STAGING  https://github.com/tianocore/edk2-staging/tree/CdePkg

Currently there are 3 examples implemented:

1. argvc: https://github.com/tianocore/edk2-staging/blob/CdePkg/CdeValidationPkg/HOSTED_ENV/argcv/main.c#L57

argc/argv handling according to https://msdn.microsoft.com/en-us/library/a1y7w461.aspx

2. systeminterfacePEI: https://github.com/tianocore/edk2-staging/blob/CdePkg/CdeValidationPkg/SYSTEM_IF/systeminterfacePEI/main.c#L57

demonstration, how PeiServices and FileHandle are passed into main()

3. systeminterfaceDXE: https://github.com/tianocore/edk2-staging/blob/CdePkg/CdeValidationPkg/SYSTEM_IF/systeminterfaceDXE/main.c#L57

demonstration, how SystemTable and ImageHandle are passed into main()

Upcoming next demonstration will be the clock() function end of this week

The idea is to bring the ANSI C Library interface into POST drivers.

This will:

1. ease porting tasks
2. allow cross development
3. allow developers to focus on their aims, because they aren’t forced to keep in mind a lot of additional info (e.g. RShiftU64)
4. provide all intrisics to allow the compiler to be a “C compiler”

(e.g. char buffer[256] = { 1 };)

What is CdePkg and Torito C Library?

• CdePkg and Torito C Library are a one man show / after work party, that is owned and written solely by myself
• CdePkg is a reference implementation only for Microsoft C compiler
• CdePkg is a feasibility study
• CdePkg is the successor of Torito C, based on the same source code
• CdePkg C Development Environment is similar to  MdePkg Module Development Environment

but guarantees  that the C compiler is always fully usable (all intrinsics available) and the C90/C95 standard library is always available

What are the design goals?

• to rewrite the whole thing from scratch, without using any public source code from GNU, BSD, Watcom
• completeness: full blown C90 + C95 support, as lowest common denominator
• tailored for UEFI: small code size, for UEFI-POST-driver uses a C-Library-Driver, that contains core/worker functions for realloc() ==  malloc() and free(),

entire printf()-family, entire scanf()-family.

UEFI-POST-driver just uses small wrapper functions to run the C-Library-Driver code.

• stable, exact, chipset independent TSC based clock() with CLOCKS_PER_SEC == 1000
• complete set of the Microsoft C-compiler intrinsic functions
• ROM-able! Runs with stack but w/o any static storage duration in .data segment, e.g. for rand(), strtok(), tmpfile()

This is required for early PEI before memory sizing, when PEI-images run directly out of flash

• Microsoft (bug) compatible (as far as possible)

1. use original Microsoft header files for UEFI Shell Apps created in VS2019
2. allow expensive debugging tasks of ANSI C .EFI applications in Visual Studio in its Windows NT counter part
3. to save my lifetime writing a documentation https://github.com/tianocore/edk2-staging/tree/CdePkg/implemented.md#validation-status

• all the above in one single C-Library CdeLib.lib

CdePkg shall be adjusted to other compilers/tool chains too, once it is feature-complete and accepted by the UEFI community.

As long as it is for Microsoft VS2019 only.

CdePkg README.md is here: https://github.com/tianocore/edk2-staging/tree/CdePkg#cdepkg

CdePkg HOWTO is here: https://github.com/tianocore/edk2-staging/blob/CdePkg/README.md#howto

CdeValidationPkg README.md is here: https://github.com/tianocore/edk2-staging/blob/CdePkg/CdeValidationPkg/README.md

CdeValidationPkg HOWTO is here: https://github.com/tianocore/edk2-staging/blob/CdePkg/CdeValidationPkg/README.md

HOWTO:

1. clone the edk2-staging repository
2. checkout CdePkg
3. run LAUNCH.BAT
4. run build -p EmulatorPkg\EmulatorPkg.dsc -t VS2015x86 -a IA32
5. run DBGEMU.BAT to start emulation (EmulatorPkg)
6. run build -a IA32 -a X64 -n 5 -t VS2015x86 -b DEBUG -p Vlv2TbltDevicePkg\PlatformPkgX64.dsc
7. update MinnowBoard with Build/Vlv2TbltDevicePkgX64\DEBUG_VS2015x86\FV\VLV.fd

Best regards,

Kilian Kegel