| 1 | EDK II Standard Libraries
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| 2 | ReadMe
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| 3 | Beta Release
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| 4 | 4:03 PM 8/2/2011
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| 5 |
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| 6 |
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| 7 | OVERVIEW
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| 8 | ========
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| 9 | This document describes the EDK II specific aspects of installing, building, and
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| 10 | using the Standard C Library component of the EDK II Application Development
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| 11 | Kit, EADK.
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| 12 |
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| 13 | The EADK is comprised of three packages: AppPkg, StdLib, and StdLibPrivateInternalFiles.
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| 14 |
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| 15 | AppPkg This package contains applications which demonstrate use of the
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| 16 | Standard C Library.
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| 17 | These applications reside in AppPkg/Applications.
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| 18 |
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| 19 | Enquire This is a program that determines many properties of the
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| 20 | C compiler and the target machine that Enquire is run on. The
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| 21 | only changes required to port this 1990s era Unix program to
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| 22 | EDK II were the addition of eight pragmas to enquire.c in
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| 23 | order to disable some Microsoft VC++ specific warnings.
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| 24 |
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| 25 | Hello This is a very simple EDK II native application that doesn't use
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| 26 | any features of the Standard C Library.
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| 27 |
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| 28 | Main This application is functionally identical to Hello, except that
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| 29 | it uses the Standard C Library to provide a main() entry point.
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| 30 |
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| 31 | Python A port of the Python-2.7.1 interpreter for UEFI. This
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| 32 | application is disabled by default. Un-comment the line for
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| 33 | PythonCore.inf in the [Components] section of AppPkg.dsc to
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| 34 | enable building Python.
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| 35 |
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| 36 | Sockets A collection of applications demonstrating use of the
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| 37 | EDK II Socket Libraries. These applications include:
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| 38 |
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| 39 | * DataSink
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| 40 | * DataSource
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| 41 | * GetHostByAddr
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| 42 | * GetHostByDns
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| 43 | * GetHostByName
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| 44 | * GetNetByAddr
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| 45 | * GetNetByName
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| 46 | * GetServByName
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| 47 | * GetServByPort
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| 48 | * RecvDgram
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| 49 | * SetHostName
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| 50 | * SetSockOpt
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| 51 | * TftpServer
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| 52 | * WebServer
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| 53 |
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| 54 | StdLib The StdLib package contains the standard header files as well as
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| 55 | implementations of the standard libraries.
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| 56 |
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| 57 | StdLibPrivateInternalFiles The contents of this package are for the
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| 58 | exclusive use of the library implementations in StdLib. Please do
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| 59 | not use anything from this package in your application or else
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| 60 | unexpected behavior may occur.
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| 61 | This package may be removed in a future release.
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| 62 |
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| 63 |
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| 64 | RELEASE NOTES
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| 65 | =============
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| 66 | This release of the EADK has some restrictions, as described below.
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| 67 |
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| 68 | 1. Only the Microsoft VS2005 and VS2008, Intel C Compiler 10.1 (or later),
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| 69 | GCC 4.3 (mingw32), GCC 4.4, and GCC 4.5 C compilers are supported for
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| 70 | Ia32 or X64 CPU architectures.
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| 71 |
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| 72 | 2. The target machine must be running firmware which provides the
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| 73 | UEFI 2.3 HII protocol.
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| 74 |
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| 75 | 3. The EADK has not been through Intel's Quality Assurance process. This
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| 76 | means that specified standards compliance has not been validated, nor
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| 77 | has it undergone formal functionality testing.
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| 78 |
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| 79 | 4. Applications must be launched from within the EFI Shell.
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| 80 |
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| 81 | 5. All file paths must use the forward slash, '/', as the separator
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| 82 | character.
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| 83 |
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| 84 | 6. Absolute file paths may optionally be prefixed by a volume specifier
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| 85 | such as "FS0:". The volume specifier is separated from the remainder
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| 86 | of the path by a single colon ':'. The volume specifier must be one of
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| 87 | the Shell's mapped volume names as shown by the "map" command.
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| 88 |
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| 89 | 7. Absolute file paths that don't begin with a volume specifier;
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| 90 | e.g. paths that begin with "/", are relative to the currently selected
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| 91 | volume. When the EFI Shell starts, there is NO selected volume.
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| 92 |
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| 93 | 8. The tmpfile(), and related, functions require that the current volume
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| 94 | have a temporary directory as specified in <paths.h>. This directory
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| 95 | is specified by macro _PATH_TMP.
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| 96 |
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| 97 | The Standard C Library provided by this package is a "hosted" implementation
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| 98 | conforming to the ISO/IEC 9899-1990 C Language Standard with Addendum 1. This
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| 99 | is commonly referred to as the "C 95" specification or ISO/IEC 9899:199409.
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| 100 | The following instructions assume that you have an existing EDK II or UDK 2010
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| 101 | source tree that has been configured to build with your tool chain. For
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| 102 | convenience, it is assumed that your EDK II source tree is located at
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| 103 | C:\Source\Edk2.
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| 104 |
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| 105 |
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| 106 | INSTALLATION
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| 107 | ============
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| 108 | The EADK is integrated within the EDK II source tree and is included with
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| 109 | current EDK II check-outs. If they are missing from your tree, they may be
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| 110 | installed by extracting, downloading or copying them to the root of your EDK II
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| 111 | source tree. The three package directories should be peers to the Conf,
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| 112 | MdePkg, Nt32Pkg, etc. directories.
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| 113 |
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| 114 | The Python 2.7.1 distribution must be downloaded from python.org before the
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| 115 | Python application can be built. Extracting Python-2.7.1.tgz into the
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| 116 | AppPkg\Applications\Python directory will produce a Python-2.7.1 directory
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| 117 | containing the Python distribution. Python files that had to be modified for
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| 118 | EDK II are in the AppPkg\Applications\Python\PyMod-2.7.1 directory. These
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| 119 | files need to be copied into the corresponding directories within Python-2.7.1.
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| 120 |
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| 121 | There are some boiler-plate declarations and definitions that need to be
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| 122 | included in your application's INF and DSC build files. These are described
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| 123 | in the CONFIGURATION section, below.
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| 124 |
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| 125 |
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| 126 | BUILDING
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| 127 | ========
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| 128 | It is not necessary to build the libraries separately from the target
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| 129 | application(s). If the application references the libraries, as described in
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| 130 | USAGE, below; the required libraries will be built as needed.
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| 131 | To build the applications included in AppPkg, one would execute the following
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| 132 | commands within the "Visual Studio Command Prompt" window:
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| 133 |
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| 134 | > cd C:\Source\Edk2
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| 135 | > .\edksetup.bat
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| 136 | > build ?a X64 ?p AppPkg\AppPkg.dsc
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| 137 |
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| 138 | This will produce the application executables: Enquire.efi, Hello.efi, and
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| 139 | Main.efi in the C:\Source\Edk2\Build\AppPkg\DEBUG_VS2008\X64 directory; with
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| 140 | the DEBUG_VS2008 component being replaced with the actual tool chain and build
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| 141 | type you have selected in Conf\Tools_def.txt. These executables can now be
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| 142 | loaded onto the target platform and executed.
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| 143 |
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| 144 | If you examine the AppPkg.dsc file, you will notice that the StdLib package is
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| 145 | referenced in order to resolve the library classes comprising the Standard
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| 146 | C Library. This, plus referencing the StdLib package in your application's
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| 147 | .inf file is all that is needed to link your application to the standard
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| 148 | libraries.
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| 149 |
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| 150 |
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| 151 | USAGE
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| 152 | =====
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| 153 | This implementation of the Standard C Library is comprised of 16 separate
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| 154 | libraries in addition to the standard header files. Nine of the libraries are
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| 155 | associated with use of one of the standard headers; thus, if the header is used
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| 156 | in an application, it must be linked with the associated library. Three
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| 157 | libraries are used to provide the Console and File-system device abstractions.
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| 158 | The libraries and associated header files are described in the following table.
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| 159 |
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| 160 | Library
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| 161 | Class Header File(s) Notes
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| 162 | ---------- ---------------- -------------------------------------------------
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| 163 | LibC -- Use Always -- This library is always required.
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| 164 | LibCtype ctype.h, wctype.h Character classification and mapping
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| 165 | LibLocale locale.h Localization types, macros, and functions
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| 166 | LibMath math.h Mathematical functions, types, and macros
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| 167 | LibStdio stdio.h Standard Input and Output functions, types, and
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| 168 | macros
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| 169 | LibStdLib stdlib.h General Utilities for numeric conversion, random
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| 170 | num., etc.
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| 171 | LibString string.h String copying, concatenation, comparison,
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| 172 | & search
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| 173 | LibSignal signal.h Functions and types for handling run-time
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| 174 | conditions
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| 175 | LibTime time.h Time and Date types, macros, and functions
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| 176 | LibUefi sys/EfiSysCall.h Provides the UEFI system interface and
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| 177 | "System Calls"
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| 178 | LibWchar wchar.h Extended multibyte and wide character utilities
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| 179 | LibNetUtil Network address and number manipulation utilities
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| 180 | DevConsole Automatically provided File I/O abstractions for
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| 181 | the UEFI Console device. No need to list this
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| 182 | library class in your INF file(s).
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| 183 | DevShell Add if desired File I/O abstractions using UEFI shell
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| 184 | facilities. Add this to the application's main
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| 185 | INF file if file-system access needed.
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| 186 | DevUtility -- Do Not Use -- Utility functions used by the Device abstractions
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| 187 | LibGdtoa -- Do Not Use -- This library is used internally and should not
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| 188 | need to be explicitly specified by an
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| 189 | application. It must be defined as one of the
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| 190 | available library classes in the application's
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| 191 | DSC file.
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| 192 |
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| 193 | Table 1: Standard Libraries
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| 194 | ============================
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| 195 |
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| 196 |
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| 197 | These libraries must be fully described in the [LibraryClasses] section of the
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| 198 | application package's DSC file. Then, each individual application needs to
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| 199 | specify which libraries to link to by specifying the Library Class, from the
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| 200 | above table, in the [LibraryClasses] section of the application's INF file. The
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| 201 | AppPkg.dsc, StdLib.dsc, and Enquire.inf files provide good examples of this.
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| 202 | More details are in the CONFIGURATION section, below.
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| 203 |
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| 204 | Within the source files of the application, use of the Standard headers and
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| 205 | library functions follow standard C programming practices as formalized by
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| 206 | ISO/IEC 9899:1990, with Addendum 1, (C 95) C language specification.
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| 207 |
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| 208 |
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| 209 | CONFIGURATION
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| 210 | =============
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| 211 | DSC Files
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| 212 | ---------
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| 213 |
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| 214 | All EDK II packages which build applications that use the standard libraries
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| 215 | must include some "boilerplate" text in the package's .dsc file. To make it
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| 216 | easier, and to reduce cut-and-paste errors, the "boilerplate" text has been
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| 217 | consolidated into a single file, StdLib/StdLib.inc, which can be included in
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| 218 | your .dsc file using the !include directive. The provided AppPkg.dsc and
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| 219 | StdLib.dsc files do this on their last line.
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| 220 |
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| 221 | Each affected section of the DSC file is described below.
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| 222 |
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| 223 | [LibraryClasses]
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| 224 | #
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| 225 | # Common Libraries
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| 226 | #
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| 227 | BaseLib|MdePkg/Library/BaseLib/BaseLib.inf
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| 228 | BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
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| 229 |
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| 230 | TimerLib|PerformancePkg/Library/DxeTscTimerLib/DxeTscTimerLib.inf
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| 231 | # To run in an emulation environment, such as NT32, comment out
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| 232 | # the TimerLib description above and un-comment the line below.
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| 233 | # TimerLib| MdePkg/Library/BaseTimerLibNullTemplate/BaseTimerLibNullTemplate.inf
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| 234 |
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| 235 | #
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| 236 | # C Standard Libraries
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| 237 | #
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| 238 | LibC|StdLib/LibC/LibC.inf
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| 239 | LibStdLib|StdLib/LibC/StdLib/StdLib.inf
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| 240 | LibString|StdLib/LibC/String/String.inf
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| 241 | LibWchar|StdLib/LibC/Wchar/Wchar.inf
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| 242 | LibCType|StdLib/LibC/Ctype/Ctype.inf
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| 243 | LibTime|StdLib/LibC/Time/Time.inf
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| 244 | LibStdio|StdLib/LibC/Stdio/Stdio.inf
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| 245 | LibGdtoa|StdLib/LibC/gdtoa/gdtoa.inf
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| 246 | LibLocale|StdLib/LibC/Locale/Locale.inf
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| 247 | LibUefi|StdLib/LibC/Uefi/Uefi.inf
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| 248 | LibMath|StdLib/LibC/Math/Math.inf
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| 249 | LibSignal|StdLib/LibC/Signal/Signal.inf
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| 250 | LibNetUtil|StdLib/LibC/LibGcc/LibGcc.inf
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| 251 |
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| 252 | # Libraries for device abstractions within the Standard C Library.
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| 253 | # Applications should not directly access any functions defined
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| 254 | # in these libraries.
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| 255 | DevUtility|StdLib/LibC/Uefi/Devices/daUtility.inf
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| 256 | DevConsole|StdLib/LibC/Uefi/Devices/daConsole.inf
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| 257 | DevShell|StdLib/LibC/Uefi/Devices/daShell.inf
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| 258 |
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| 259 | Figure 1: Library Class Descriptions
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| 260 | ====================================
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| 261 |
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| 262 |
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| 263 | Descriptions of the Library Classes comprising the Standard Libraries must be
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| 264 | included in your application package's DSC file, as shown in Figure 1: Library
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| 265 | Class Descriptions, above.
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| 266 |
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| 267 | The directives in Figure 2: Package Component Descriptions will create
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| 268 | instances of the BaseLib and BaseMemoryLib library classes that are built
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| 269 | with Link-time-Code-Generation disabled. This is necessary when using the
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| 270 | Microsoft tool chains in order to allow the library's functions to be
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| 271 | resolved during the second pass of the linker during Link-Time-Code-Generation
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| 272 | of the application.
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| 273 |
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| 274 | [Components]
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| 275 | # BaseLib and BaseMemoryLib need to be built with the /GL- switch
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| 276 | # when using the Microsoft tool chains. This is required so that
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| 277 | # the library functions can be resolved during the second pass of
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| 278 | # the linker during link-time-code-generation.
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| 279 | #
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| 280 | MdePkg/Library/BaseLib/BaseLib.inf {
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| 281 | <BuildOptions>
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| 282 | MSFT:*_*_*_CC_FLAGS = /X /Zc:wchar_t /GL-
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| 283 | }
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| 284 | MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf {
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| 285 | <BuildOptions>
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| 286 | MSFT:*_*_*_CC_FLAGS = /X /Zc:wchar_t /GL-
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| 287 | }
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| 288 |
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| 289 | Figure 2: Package Component Descriptions
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| 290 | ========================================
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| 291 |
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| 292 |
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| 293 | The NULL TimerLib instance must be selected if you desire to run your
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| 294 | application under an emulation environment -- unless there is a supported
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| 295 | TimerLib for that environment. For example, the InOsEmuPkg provides a
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| 296 | DxeTimerLib which can be used for the TimerLib instance.
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| 297 |
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| 298 | The "boilerplate" text in StdLib.inc will automatically adjust which Timer
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| 299 | Library is instantiated based upon whether the $(EMULATE) macro has been
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| 300 | defined, or not.
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| 301 |
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| 302 | ###
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| 303 | # Select the correct TimerLib instance depending upon whether running under
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| 304 | # an emulation environment, or not.
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| 305 | !ifndef $(EMULATE)
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| 306 | # Not running in an Emulation Environment
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| 307 | [LibraryClasses.IA32.UEFI_APPLICATION]
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| 308 | TimerLib|PerformancePkg/Library/DxeTscTimerLib/DxeTscTimerLib.inf
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| 309 |
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| 310 | [LibraryClasses.X64.UEFI_APPLICATION]
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| 311 | TimerLib|PerformancePkg/Library/DxeTscTimerLib/DxeTscTimerLib.inf
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| 312 |
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| 313 | [LibraryClasses.IPF.UEFI_APPLICATION]
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| 314 | PalLib|MdePkg/Library/UefiPalLib/UefiPalLib.inf
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| 315 | TimerLib|MdePkg/Library/SecPeiDxeTimerLibCpu/SecPeiDxeTimerLibCpu.inf
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| 316 |
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| 317 | !else
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| 318 | # Use this instance if Running in an Emulation Environment.
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| 319 | [LibraryClasses.Common.UEFI_APPLICATION]
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| 320 | TimerLib|MdePkg/Library/BaseTimerLibNullTemplate/BaseTimerLibNullTemplate.inf
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| 321 | !endif
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| 322 |
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| 323 | Figure 3: Timer Library Selection
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| 324 | =================================
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| 325 |
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| 326 |
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| 327 | Each compiler assumes, by default, that it will be used with standard libraries
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| 328 | and headers provided by the compiler vendor. Many of these assumptions are
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| 329 | incorrect for the UEFI environment. By including a BuildOptions section, as
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| 330 | shown in Figure 3: Package Build Options, these assumptions can be
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| 331 | tailored for compatibility with UEFI and the EDK II Standard Libraries.
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| 332 |
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| 333 | [BuildOptions]
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| 334 | INTEL:*_*_IA32_CC_FLAGS = /Qfreestanding
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| 335 | MSFT:*_*_IA32_CC_FLAGS = /X /Zc:wchar_t
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| 336 | GCC:*_*_IA32_CC_FLAGS = /ffreestanding ?nostdinc ?nostdlib
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| 337 |
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| 338 | # The Build Options, below, are only used when building the C library
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| 339 | # to be run under an emulation environment. The clock() system call
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| 340 | # is modified to return -1 indicating that it is unsupported.
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| 341 | # Just un-comment the lines below and select the correct
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| 342 | # TimerLib instance, above.
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| 343 |
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| 344 | # INTEL:*_*_IA32_CC_FLAGS = /D NT32dvm
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| 345 | # MSFT:*_*_IA32_CC_FLAGS = /D NT32dvm
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| 346 | # GCC:*_*_IA32_CC_FLAGS = -DNT32dvm
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| 347 |
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| 348 | Figure 4: Package Build Options
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| 349 | ===============================
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| 350 |
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| 351 | The "boilerplate" text can be included using a !include directive in the
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| 352 | package's .dsc file. The provided AppPkg.dsc and StdLib.dsc files include
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| 353 | the "boilerplate" text as follows:
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| 354 |
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| 355 | # Include Boilerplate text required for building with the Standard Libraries.
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| 356 | #
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| 357 | #############################################################################
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| 358 | !include StdLib/StdLib.inc
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| 359 |
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| 360 | Figure 5: "Boilerplate" Inclusion
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| 361 | =================================
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| 362 |
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| 363 |
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| 364 | INF Files
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| 365 | =========
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| 366 | The INF files for most modules will not require special directives in order to
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| 367 | support the Standard Libraries. The two cases which could occur are described
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| 368 | below.
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| 369 |
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| 370 | [LibraryClasses]
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| 371 | UefiLib
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| 372 | LibC
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| 373 | LibString
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| 374 | LibStdio
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| 375 | DevShell
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| 376 |
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| 377 | Figure 6: Module Library Classes
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| 378 | ================================
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| 379 |
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| 380 |
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| 381 | Modules of type UEFI_APPLICATION that perform file I/O should include library
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| 382 | class DevShell. Including this library class will allow file operations to be
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| 383 | handled by the UEFI Shell. Without this class, only Console I/O is permitted.
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| 384 |
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| 385 | [BuildOptions]
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| 386 | INTEL:*_*_*_CC_FLAGS = /Qdiag-disable:181,186
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| 387 | MSFT:*_*_*_CC_FLAGS = /Oi- /wd4018 /wd4131
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| 388 | GCC:*_*_IPF_SYMRENAME_FLAGS = --redefine-syms=Rename.txt
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| 389 |
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| 390 | Figure 7: Module Build Options
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| 391 | ==============================
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| 392 |
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| 393 |
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| 394 | An application's INF file may need to include a [BuildOptions] section
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| 395 | specifying additional compiler and linker flags necessary to allow the
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| 396 | application to be built. Usually, this section is not needed. When building
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| 397 | code from external sources, though, it may be necessary to disable some
|
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| 398 | warnings or enable/disable some compiler features.
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| 399 |
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| 400 |
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| 401 | IMPLEMENTATION-Specific Features
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| 402 | ================================
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| 403 | It is very strongly recommended that applications not use the long or
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| 404 | unsigned long types. The size of this type varies between compilers and is one
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| 405 | of the less portable aspects of C. Instead, one should use the UEFI defined
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| 406 | types whenever possible. Use of these types, listed below for reference,
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| 407 | ensures that the declared objects have unambiguous, explicitly declared, sizes
|
|---|
| 408 | and characteristics.
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| 409 |
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| 410 | UINT64 INT64 UINT32 INT32 UINT16 CHAR16
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| 411 | INT16 BOOLEAN UINT8 CHAR8 INT8
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| 412 | UINTN INTN PHYSICALADDRESS
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| 413 |
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| 414 | There are similar types declared in sys/types.h and related files.
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| 415 |
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| 416 | The types UINTN and INTN have the native width of the target processor
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| 417 | architecture. Thus, INTN on IA32 has a width of 32 bits while INTN on X64 and
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| 418 | IPF has a width of 64 bits.
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| 419 |
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| 420 | For maximum portability, data objects intended to hold addresses should be
|
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| 421 | declared with type intptr_t or uintptr_t. These types, declared in
|
|---|
| 422 | sys/stdint.h, can be used to create objects capable of holding pointers. Note
|
|---|
| 423 | that these types will generate different sized objects on different processor
|
|---|
| 424 | architectures. If a constant size across all processors and compilers is
|
|---|
| 425 | needed, use type PHYSICAL_ADDRESS.
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|---|
| 426 |
|
|---|
| 427 | Though not specifically required by the ISO/IEC 9899 standard, this
|
|---|
| 428 | implementation of the Standard C Library provides the following system calls
|
|---|
| 429 | which are declared in sys/EfiSysCall.h.
|
|---|
| 430 |
|
|---|
| 431 | close dup dup2 fcntl
|
|---|
| 432 | fstat getcwd ioctl isatty
|
|---|
| 433 | lseek lstat mkdir open
|
|---|
| 434 | poll read rename rmdir
|
|---|
| 435 | stat unlink write
|
|---|
| 436 |
|
|---|
| 437 | The open function will accept file names of "stdin:", "stdout:", and "stderr:"
|
|---|
| 438 | which cause the respective streams specified in the UEFI System Table to be
|
|---|
| 439 | opened. Normally, these are associated with the console device. When the
|
|---|
| 440 | application is first started, these streams are automatically opened on File
|
|---|
| 441 | Descriptors 0, 1, and 2 respectively.
|
|---|
| 442 |
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| 443 |
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