EADK | |
EDK II Standard Libraries and Applications | |
ReadMe | |
Beta-1 Release | |
27 Jan. 2012 | |
DRAFT | |
OVERVIEW | |
======== | |
The EADK (uEfi Application Development Kit) provides a set of standards-based | |
libraries, along with utility and demonstration applications, intended to | |
ease development of UEFI applications based upon the EDK II Open-Source | |
distribution. | |
At this time, applications developed with the EADK are intended to reside | |
on, and be loaded from, storage separate from the core firmware. This is | |
primarily due to size and environmental requirements. | |
Some components of the EADK can be built as drivers. These will be identified | |
explicitly in their documentation. | |
This document describes the EDK II specific aspects of installing, building, | |
and using the Standard C Library component of the EDK II Application | |
Development Kit, EADK. | |
The EADK is comprised of three packages: | |
AppPkg, StdLib, and StdLibPrivateInternalFiles. | |
AppPkg This package contains applications which demonstrate use of the | |
Standard C Library. | |
These applications reside in AppPkg/Applications. | |
Enquire This is a program that determines many properties of the | |
C compiler and the target machine that Enquire is run on. The | |
only changes required to port this 1990s era Unix program to | |
EDK II were the addition of eight pragmas to enquire.c in | |
order to disable some Microsoft VC++ specific warnings. | |
Hello This is a very simple EDK II native application that doesn't use | |
any features of the Standard C Library. | |
Main This application is functionally identical to Hello, except that | |
it uses the Standard C Library to provide a main() entry point. | |
Python A port of the Python-2.7.2 interpreter for UEFI. This | |
application is disabled by default. | |
See the PythonReadMe.txt file, in the Python directory, | |
for information on configuring and building Python. | |
Sockets A collection of applications demonstrating use of the | |
EDK II Socket Libraries. These applications include: | |
* DataSink | |
* DataSource | |
* GetAddrInfo | |
* GetHostByAddr | |
* GetHostByDns | |
* GetHostByName | |
* GetNetByAddr | |
* GetNetByName | |
* GetServByName | |
* GetServByPort | |
* OobRx | |
* OobTx | |
* RawIp4Rx | |
* RawIp4Tx | |
* RecvDgram | |
* SetHostName | |
* SetSockOpt | |
* TftpServer | |
* WebServer | |
StdLib The StdLib package contains the standard header files as well as | |
implementations of standards based libraries. | |
* BsdSocketLib | |
Support routines above the sockets layer and C interface for | |
the UEFI socket library. | |
* Efi | |
Template contents for the target system's | |
\Efi\StdLib\etc directory. | |
* EfiSocketLib | |
UEFI socket implementation, may be linked into an | |
application or run as a driver. | |
* Include | |
Standard include files. | |
* LibC | |
C Standard Library implementation as per | |
ISO/IEC 9899:199409 (C95). | |
* PosixLib | |
Selected functions from the "Single Unix v4" specification. | |
* SocketDxe | |
UEFI sockets driver, includes EfiSocketLib. | |
* UseSocketDxe | |
Alternate linkage for applications that get built into the | |
firmware. Cause application to use a common instance of the | |
sockets driver instead of including all of sockets into the | |
application. | |
StdLibPrivateInternalFiles The contents of this package are for the | |
exclusive use of the library implementations in StdLib. Please do | |
not use anything from this package in your application or else | |
unexpected behavior may occur. | |
This package may be removed in a future release. | |
RELEASE NOTES | |
============= | |
Fixes and Additions | |
------------------- | |
Beginning with this release, applications built with the StdLib package | |
no longer have a dependency on the TimerLib. | |
Known Issues | |
----------------- | |
This release of the EADK has some restrictions, as described below. | |
1. Only the Microsoft VS2005 and VS2008, Intel C Compiler 10.1 (or later), | |
GCC 4.3 (mingw32), GCC 4.4, and GCC 4.5 C compilers are supported for | |
Ia32 or X64 CPU architectures. Others may work but have not been tested. | |
2. The target machine must be running firmware which provides the | |
UEFI 2.3 HII protocol. | |
3. The EADK has not been through Intel's Quality Assurance process. This | |
means that specified standards compliance has not been validated, nor | |
has it undergone formal functionality testing. | |
4. Applications must be launched from within the EFI Shell. | |
6. Absolute file paths may optionally be prefixed by a volume specifier | |
such as "FS0:". The volume specifier is separated from the remainder | |
of the path by a single colon ':'. The volume specifier must be one of | |
the Shell's mapped volume names as shown by the "map" command. | |
7. Absolute file paths that don't begin with a volume specifier; | |
e.g. paths that begin with "/", are relative to the currently selected | |
volume. When the EFI Shell first starts, there is NO selected volume. | |
8. The tmpfile(), and related, functions require that the current volume | |
have a temporary directory as specified in <paths.h>. This directory | |
is specified by macro _PATH_TMP as /Efi/StdLib/tmp. | |
9. Input line editing is not supported. Backspacing, deleting, or | |
otherwise attempting to modify interactive input will result in a | |
syntax error since the editing characters are interpreted the | |
same as any other character. | |
The Standard C Library provided by this package is a "hosted" implementation | |
conforming to the ISO/IEC 9899-1990 C Language Standard with Addendum 1. This | |
is commonly referred to as the "C 95" specification or ISO/IEC 9899:199409. | |
The following instructions assume that you have an existing EDK II or UDK 2010 | |
source tree that has been configured to build with your tool chain. For | |
convenience, it is assumed that your EDK II source tree is located at | |
C:\Source\Edk2. | |
EADK INSTALLATION | |
================= | |
The EADK is integrated within the EDK II source tree and is included with | |
current EDK II check-outs. If they are missing from your tree, they may be | |
installed by extracting, downloading or copying them to the root of your EDK II | |
source tree. The three package directories should be peers to the Conf, | |
MdePkg, Nt32Pkg, etc. directories. | |
The Python 2.7.2 distribution must be downloaded from python.org before the | |
Python application can be built. Extracting Python-2.7.2.tgz into the | |
AppPkg\Applications\Python directory will produce a Python-2.7.2 directory | |
containing the Python distribution. Python files that had to be modified for | |
EDK II are in the AppPkg\Applications\Python\PyMod-2.7.2 directory. These | |
files need to be copied into the corresponding directories within Python-2.7.2. | |
The Python 2.7.1 port was superseded before it was completed. The PyMod-2.7.1 | |
directory tree will be deleted in the near future. Use the Python 2.7.2 port, | |
as described above. | |
There are some boiler-plate declarations and definitions that need to be | |
included in your application's INF and DSC build files. These are described | |
in the CONFIGURATION section, below. | |
BUILDING | |
======== | |
It is not necessary to build the libraries separately from the target | |
application(s). If the application references the libraries, as described in | |
USAGE, below; the required libraries will be built as needed. | |
To build the applications included in AppPkg, one would execute the following | |
commands within the "Visual Studio Command Prompt" window: | |
> cd C:\Source\Edk2 | |
> .\edksetup.bat | |
> build -a X64 -p AppPkg\AppPkg.dsc | |
This will produce the application executables: Enquire.efi, Hello.efi, and | |
Main.efi in the C:\Source\Edk2\Build\AppPkg\DEBUG_VS2008\X64 directory; with | |
the DEBUG_VS2008 component being replaced with the actual tool chain and build | |
type you have selected in Conf\Tools_def.txt. These executables can now be | |
loaded onto the target platform and executed. | |
If you examine the AppPkg.dsc file, you will notice that the StdLib package is | |
referenced in order to resolve the library classes comprising the Standard | |
C Library. This, plus referencing the StdLib package in your application's | |
.inf file is all that is needed to link your application to the standard | |
libraries. | |
Unless explicitly stated as allowed, EADK components should not be added as | |
components of a DSC file which builds a platform's core firmware. There are | |
incompatibilities in build flags and requirements that will conflict with the | |
requirements of the core firmware. EADK components should be built using a | |
separate DSC file then, if absolutely necessary, included as binary components | |
of other DSC files. | |
USAGE | |
===== | |
This implementation of the Standard C Library is comprised of 16 separate | |
libraries in addition to the standard header files. Nine of the libraries are | |
associated with use of one of the standard headers; thus, if the header is used | |
in an application, it must be linked with the associated library. Three | |
libraries are used to provide the Console and File-system device abstractions. | |
The libraries and associated header files are described in the following table. | |
Library | |
Class Header File(s) Notes | |
---------- ---------------- ------------------------------------------------- | |
LibC -- Use Always -- This library is always required. | |
LibCtype ctype.h, wctype.h Character classification and mapping | |
LibLocale locale.h Localization types, macros, and functions | |
LibMath math.h Mathematical functions, types, and macros | |
LibStdio stdio.h Standard Input and Output functions, types, and | |
macros | |
LibStdLib stdlib.h General Utilities for numeric conversion, random | |
num., etc. | |
LibString string.h String copying, concatenation, comparison, | |
& search | |
LibSignal signal.h Functions and types for handling run-time | |
conditions | |
LibTime time.h Time and Date types, macros, and functions | |
LibUefi sys/EfiSysCall.h Provides the UEFI system interface and | |
"System Calls" | |
LibWchar wchar.h Extended multibyte and wide character utilities | |
LibNetUtil Network address and number manipulation utilities | |
DevConsole Automatically provided File I/O abstractions for | |
the UEFI Console device. No need to list this | |
library class in your INF file(s). | |
DevShell Add if desired File I/O abstractions using UEFI shell | |
facilities. Add this to the application's main | |
INF file if file-system access needed. | |
DevUtility -- Do Not Use -- Utility functions used by the Device abstractions | |
LibGdtoa -- Do Not Use -- This library is used internally and should not | |
need to be explicitly specified by an | |
application. It must be defined as one of the | |
available library classes in the application's | |
DSC file. | |
Table 1: Standard Libraries | |
============================ | |
These libraries must be fully described in the [LibraryClasses] section of the | |
application package's DSC file. Then, each individual application needs to | |
specify which libraries to link to by specifying the Library Class, from the | |
above table, in the [LibraryClasses] section of the application's INF file. The | |
AppPkg.dsc, StdLib.dsc, and Enquire.inf files provide good examples of this. | |
More details are in the CONFIGURATION section, below. | |
Within the source files of the application, use of the Standard headers and | |
library functions follow standard C programming practices as formalized by | |
ISO/IEC 9899:1990, with Addendum 1, (C 95) C language specification. | |
BUILD CONFIGURATION | |
=================== | |
DSC Files | |
--------- | |
All EDK II packages which build applications that use the standard libraries | |
must include some "boilerplate" text in the package's .dsc file. To make it | |
easier, and to reduce cut-and-paste errors, the "boilerplate" text has been | |
consolidated into a single file, StdLib/StdLib.inc, which can be included in | |
your .dsc file using the !include directive. The provided AppPkg.dsc and | |
StdLib.dsc files do this on their last line. | |
Each section of StdLib/StdLib.inc is described below. | |
[LibraryClasses] | |
# | |
# C Standard Libraries | |
# | |
LibC|StdLib/LibC/LibC.inf | |
LibCType|StdLib/LibC/Ctype/Ctype.inf | |
LibLocale|StdLib/LibC/Locale/Locale.inf | |
LibMath|StdLib/LibC/Math/Math.inf | |
LibSignal|StdLib/LibC/Signal/Signal.inf | |
LibStdio|StdLib/LibC/Stdio/Stdio.inf | |
LibStdLib|StdLib/LibC/StdLib/StdLib.inf | |
LibString|StdLib/LibC/String/String.inf | |
LibTime|StdLib/LibC/Time/Time.inf | |
LibUefi|StdLib/LibC/Uefi/Uefi.inf | |
LibWchar|StdLib/LibC/Wchar/Wchar.inf | |
# Common Utilities for Networking Libraries | |
LibNetUtil|StdLib/LibC/NetUtil/NetUtil.inf | |
# Additional libraries for POSIX functionality. | |
LibErr|StdLib/PosixLib/Err/LibErr.inf | |
LibGen|StdLib/PosixLib/Gen/LibGen.inf | |
LibGlob|StdLib/PosixLib/Glob/LibGlob.inf | |
LibStringlist|StdLib/PosixLib/Stringlist/LibStringlist.inf | |
# Libraries for device abstractions within the Standard C Library | |
# Applications should not directly access any functions defined in these libraries. | |
LibGdtoa|StdLib/LibC/gdtoa/gdtoa.inf | |
DevConsole|StdLib/LibC/Uefi/Devices/daConsole.inf | |
DevShell|StdLib/LibC/Uefi/Devices/daShell.inf | |
DevUtility|StdLib/LibC/Uefi/Devices/daUtility.inf | |
[LibraryClasses.ARM.UEFI_APPLICATION] | |
NULL|ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf | |
Figure 1: Library Class Descriptions | |
==================================== | |
Descriptions of the Library Classes comprising the Standard Libraries, | |
as shown above in Figure 1: Library Class Descriptions, are provided. | |
The directives in Figure 2: Package Component Descriptions will create | |
instances of the BaseLib and BaseMemoryLib library classes that are built | |
with Link-time-Code-Generation disabled. This is necessary when using the | |
Microsoft tool chains in order to allow the library's functions to be | |
resolved during the second pass of the linker during Link-Time-Code-Generation | |
of the application. | |
A DXE driver version of the Socket library is also built. | |
[Components] | |
# BaseLib and BaseMemoryLib need to be built with the /GL- switch | |
# when using the Microsoft tool chains. This is required so that | |
# the library functions can be resolved during the second pass of | |
# the linker during link-time-code-generation. | |
# | |
MdePkg/Library/BaseLib/BaseLib.inf { | |
<BuildOptions> | |
MSFT:*_*_*_CC_FLAGS = /X /Zc:wchar_t /GL- | |
} | |
MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf { | |
<BuildOptions> | |
MSFT:*_*_*_CC_FLAGS = /X /Zc:wchar_t /GL- | |
} | |
########## | |
# Socket Layer | |
########## | |
StdLib/SocketDxe/SocketDxe.inf | |
Figure 2: Package Component Descriptions | |
======================================== | |
Each compiler assumes, by default, that it will be used with standard libraries | |
and headers provided by the compiler vendor. Many of these assumptions are | |
incorrect for the UEFI environment. By including a BuildOptions section, as | |
shown in Figure 3: Package Build Options, these assumptions can be | |
tailored for compatibility with UEFI and the EDK II Standard Libraries. | |
[BuildOptions] | |
INTEL:*_*_IA32_CC_FLAGS = /Qfreestanding | |
MSFT:*_*_IA32_CC_FLAGS = /X /Zc:wchar_t | |
GCC:*_*_IA32_CC_FLAGS = -nostdinc -nostdlib | |
# The Build Options, below, are only used when building the C library | |
# to be run under an emulation environment. They disable optimization | |
# which facillitates debugging under the Emulation environment. | |
# INTEL:*_*_IA32_CC_FLAGS = /Od | |
# MSFT:*_*_IA32_CC_FLAGS = /Od | |
# GCC:*_*_IA32_CC_FLAGS = -O0 | |
Figure 4: Package Build Options | |
=============================== | |
The "boilerplate" text can be included using a !include directive in the | |
package's .dsc file. The provided AppPkg.dsc and StdLib.dsc files include | |
the "boilerplate" text as follows: | |
# Include Boilerplate text required for building with the Standard Libraries. | |
# | |
############################################################################# | |
!include StdLib/StdLib.inc | |
Figure 5: "Boilerplate" Inclusion | |
================================= | |
INF Files | |
========= | |
The INF files for most modules will not require special directives in order to | |
support the Standard Libraries. The two cases which could occur are described | |
below. | |
[LibraryClasses] | |
UefiLib | |
LibC | |
LibString | |
LibStdio | |
DevShell | |
Figure 6: Module Library Classes | |
================================ | |
Modules of type UEFI_APPLICATION that perform file I/O should include library | |
class DevShell. Including this library class will allow file operations to be | |
handled by the UEFI Shell. Without this class, only Console I/O is permitted. | |
[BuildOptions] | |
INTEL:*_*_*_CC_FLAGS = /Qdiag-disable:181,186 | |
MSFT:*_*_*_CC_FLAGS = /Oi- /wd4018 /wd4131 | |
GCC:*_*_IPF_SYMRENAME_FLAGS = --redefine-syms=Rename.txt | |
Figure 7: Module Build Options | |
============================== | |
An application's INF file may need to include a [BuildOptions] section | |
specifying additional compiler and linker flags necessary to allow the | |
application to be built. Usually, this section is not needed. When building | |
code from external sources, though, it may be necessary to disable some | |
warnings or enable/disable some compiler features. | |
TARGET-SYSTEM INSTALLATION | |
========================== | |
Applications that use file system features or the Socket library depend upon | |
the existence of a specific directory tree structure on the same volume that | |
the application was loaded from. This tree structure is described below: | |
/EFI Root of the UEFI system area. | |
|- /Tools Directory containing applications. | |
|- /Boot UEFI specified Boot directory. | |
|- /StdLib Root of the Standard Libraries sub-tree. | |
|- /etc Configuration files used by libraries. | |
|- /tmp Temporary files created by tmpfile(), etc. | |
The /Efi/StdLib/etc directory is populated from the StdLib/Efi/etc source | |
directory. | |
IMPLEMENTATION-Specific Features | |
================================ | |
It is very strongly recommended that applications not use the long or | |
unsigned long types. The size of this type varies between compilers and is one | |
of the less portable aspects of C. Instead, one should use the UEFI defined | |
types whenever possible. Use of these types, listed below for reference, | |
ensures that the declared objects have unambiguous, explicitly declared, sizes | |
and characteristics. | |
UINT64 INT64 UINT32 INT32 UINT16 CHAR16 | |
INT16 BOOLEAN UINT8 CHAR8 INT8 | |
UINTN INTN PHYSICALADDRESS | |
There are similar types declared in sys/types.h and related files. | |
The types UINTN and INTN have the native width of the target processor | |
architecture. Thus, INTN on IA32 has a width of 32 bits while INTN on X64 and | |
IPF has a width of 64 bits. | |
For maximum portability, data objects intended to hold addresses should be | |
declared with type intptr_t or uintptr_t. These types, declared in | |
sys/stdint.h, can be used to create objects capable of holding pointers. Note | |
that these types will generate different sized objects on different processor | |
architectures. If a constant size across all processors and compilers is | |
needed, use type PHYSICAL_ADDRESS. | |
Though not specifically required by the ISO/IEC 9899 standard, this | |
implementation of the Standard C Library provides the following system calls | |
which are declared in sys/EfiSysCall.h and/or unistd.h. | |
close creat chmod dup dup2 | |
fcntl fstat getcwd ioctl isatty | |
lseek lstat mkdir open poll | |
read rename rmdir stat unlink write | |
The open function will accept file names of "stdin:", "stdout:", and "stderr:" | |
which cause the respective streams specified in the UEFI System Table to be | |
opened. Normally, these are associated with the console device. When the | |
application is first started, these streams are automatically opened on File | |
Descriptors 0, 1, and 2 respectively. | |
# # # |