1 | EADK
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2 | EDK II Standard Libraries and Applications
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3 | ReadMe
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4 | Version 1.02
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5 | 21 Dec. 2012
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6 |
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7 |
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8 | OVERVIEW
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9 | ========
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10 | The EADK (uEfi Application Development Kit) provides a set of standards-based
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11 | libraries, along with utility and demonstration applications, intended to
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12 | ease development of UEFI applications based upon the EDK II Open-Source
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13 | distribution.
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14 |
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15 | At this time, applications developed with the EADK are intended to reside
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16 | on, and be loaded from, storage separate from the core firmware. This is
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17 | primarily due to size and environmental requirements.
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18 |
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19 | This release of the EADK should only be used to produce UEFI Applications. Due to the execution
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20 | environment built by the StdLib component, execution as a UEFI driver can cause system stability
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21 | issues.
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22 |
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23 | This document describes the EDK II specific aspects of installing, building,
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24 | and using the Standard C Library component of the EDK II Application
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25 | Development Kit, EADK.
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26 |
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27 | The EADK is comprised of three packages:
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28 | AppPkg, StdLib, and StdLibPrivateInternalFiles.
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29 |
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30 | AppPkg This package contains applications which demonstrate use of the
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31 | Standard C and Sockets Libraries.
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32 | These applications reside in AppPkg/Applications.
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33 |
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34 | Enquire This is a program that determines many properties of the
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35 | C compiler and the target machine that Enquire is run on. The
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36 | only changes required to port this 1990s era Unix program to
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37 | EDK II were the addition of eight pragmas to enquire.c in
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38 | order to disable some Microsoft VC++ specific warnings.
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39 |
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40 | Hello This is a very simple EDK II native application that doesn't use
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41 | any features of the Standard C Library.
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42 |
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43 | Main This application is functionally identical to Hello, except that
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44 | it uses the Standard C Library to provide a main() entry point.
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45 |
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46 | Python A port of the Python-2.7.2 interpreter for UEFI. Building this
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47 | application is disabled by default.
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48 | See the PythonReadMe.txt file, in the Python directory,
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49 | for information on configuring and building Python.
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50 |
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51 | Sockets A collection of applications demonstrating use of the
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52 | EDK II Socket Libraries. These applications include:
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53 |
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54 | * DataSink * DataSource
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55 | * GetAddrInfo * GetHostByAddr
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56 | * GetHostByDns * GetHostByName
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57 | * GetNetByAddr * GetNetByName
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58 | * GetServByName * GetServByPort
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59 | * OobRx * OobTx
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60 | * RawIp4Rx * RawIp4Tx
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61 | * RecvDgram * SetHostName
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62 | * SetSockOpt * TftpServer
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63 | * WebServer
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64 |
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65 | StdLib The StdLib package contains the standard header files as well as
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66 | implementations of other standards-based libraries.
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67 |
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68 | * BsdSocketLib
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69 | Support routines above the sockets layer and C interface for
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70 | the UEFI socket library.
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71 | * Efi
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72 | Template contents for the target system's
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73 | \Efi\StdLib\etc directory.
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74 | * EfiSocketLib
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75 | UEFI socket implementation, may be linked into an
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76 | application or run as a driver.
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77 | * Include
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78 | Standard include files.
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79 | * LibC
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80 | C Standard Library implementation as per
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81 | ISO/IEC 9899:199409 (C95).
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82 | * PosixLib
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83 | Selected functions from the "Single Unix v4" specification.
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84 | * SocketDxe
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85 | UEFI sockets driver, includes EfiSocketLib.
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86 | * UseSocketDxe
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87 | Alternate linkage for applications that get built into the
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88 | firmware. Cause application to use a common instance of the
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89 | sockets driver instead of including all of sockets into the
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90 | application.
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91 |
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92 | StdLibPrivateInternalFiles The contents of this package are for the
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93 | exclusive use of the library implementations in StdLib. Please do
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94 | not use anything from this package in your application or else
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95 | unexpected behavior may occur.
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96 | This package may be removed in a future release.
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97 |
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98 |
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99 | RELEASE NOTES
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100 | =============
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101 | Fixes and Additions
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102 | -------------------
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103 | Beginning with release 1.01, applications built with the StdLib package
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104 | no longer have a dependency on the TimerLib.
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105 |
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106 | Known Issues
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107 | -----------------
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108 | This release of the EADK has some restrictions, as described below.
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109 |
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110 | 1. The target machine must be running firmware which provides the
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111 | UEFI 2.3 HII protocol.
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112 |
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113 | 2. Applications must be launched from within the EFI Shell.
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114 |
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115 | 3. Absolute file paths may optionally be prefixed by a volume specifier
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116 | such as "FS0:". The volume specifier is separated from the remainder
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117 | of the path by a single colon ':'. The volume specifier must be one of
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118 | the Shell's mapped volume names as shown by the "map" command.
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119 |
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120 | 4. Absolute file paths that don't begin with a volume specifier;
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121 | e.g. paths that begin with "/", are relative to the currently selected
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122 | volume. When the EFI Shell first starts, there is NO selected volume.
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123 |
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124 | 5. The tmpfile(), and related, functions require that the current volume
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125 | have a temporary directory as specified in <paths.h>. This directory
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126 | is specified by macro _PATH_TMP as /Efi/StdLib/tmp.
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127 |
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128 | The Standard C Library provided by this package is a "hosted" implementation
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129 | conforming to the ISO/IEC 9899-1990 C Language Standard with Addendum 1. This
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130 | is commonly referred to as the "C 95" specification or ISO/IEC 9899:199409.
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131 | The following instructions assume that you have an existing EDK II or UDK 2010
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132 | source tree that has been configured to build with your tool chain. For
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133 | convenience, it is assumed that your EDK II source tree is located at
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134 | C:\Source\Edk2.
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135 |
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136 |
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137 | EADK INSTALLATION
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138 | =================
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139 | The EADK is integrated within the EDK II source tree and is included with
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140 | current EDK II check-outs. If they are missing from your tree, they may be
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141 | installed by extracting, downloading or copying them to the root of your EDK II
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142 | source tree. The three package directories should be peers to the Conf,
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143 | MdePkg, Nt32Pkg, etc. directories.
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144 |
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145 | There are some boiler-plate declarations and definitions that need to be
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146 | included in your application's INF and DSC build files. These are described
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147 | in the CONFIGURATION section, below.
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148 |
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149 | A subset of the Python 2.7.2 distribution is included as part of AppPkg. If desired,
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150 | the full Python 2.7.2 distribution may be downloaded from python.org and used instead.
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151 | Delete or rename the existing Python-2.7.2 directory then extract the downloaded
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152 | Python-2.7.2.tgz file into the AppPkg\Applications\Python directory. This will produce a
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153 | Python-2.7.2 directory containing the full Python distribution. Python files that had to be
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154 | modified for EDK II are in the AppPkg\Applications\Python\PyMod-2.7.2 directory. These
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155 | files need to be copied into the corresponding directories within the extracted Python-2.7.2
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156 | directory before Python can be built.
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157 |
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158 |
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159 | BUILDING
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160 | ========
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161 | It is not necessary to build the libraries separately from the target
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162 | application(s). If the application references the libraries, as described in
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163 | USAGE, below; the required libraries will be built as needed.
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164 | To build the applications included in AppPkg, one would execute the following
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165 | commands within the "Visual Studio Command Prompt" window:
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166 |
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167 | > cd C:\Source\Edk2
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168 | > .\edksetup.bat
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169 | > build -a X64 -p AppPkg\AppPkg.dsc
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170 |
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171 | This will produce the application executables: Enquire.efi, Hello.efi, and
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172 | Main.efi in the C:\Source\Edk2\Build\AppPkg\DEBUG_VS2008\X64 directory; with
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173 | the DEBUG_VS2008 component being replaced with the actual tool chain and build
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174 | type you have selected in Conf\Tools_def.txt. These executables can now be
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175 | loaded onto the target platform and executed.
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176 |
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177 | If you examine the AppPkg.dsc file, you will notice that the StdLib package is
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178 | referenced in order to resolve the library classes comprising the Standard
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179 | C Library. This, plus referencing the StdLib package in your application's
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180 | .inf file is all that is needed to link your application to the standard
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181 | libraries.
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182 |
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183 | Unless explicitly stated as allowed, EADK components should not be added as
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184 | components of a DSC file which builds a platform's core firmware. There are
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185 | incompatibilities in build flags and requirements that will conflict with the
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186 | requirements of the core firmware. EADK components should be built using a
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187 | separate DSC file then, if absolutely necessary, included as binary components
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188 | of other DSC files.
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189 |
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190 | USAGE
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191 | =====
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192 | This implementation of the Standard C Library is comprised of 16 separate
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193 | libraries in addition to the standard header files. Nine of the libraries are
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194 | associated with use of one of the standard headers; thus, if the header is used
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195 | in an application, it must be linked with the associated library. Three
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196 | libraries are used to provide the Console and File-system device abstractions.
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197 | The libraries and associated header files are described in the following table.
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198 |
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199 | Library
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200 | Class Header File(s) Notes
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201 | ---------- ---------------- -------------------------------------------------
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202 | LibC -- Use Always -- This library is always required.
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203 | LibCtype ctype.h, wctype.h Character classification and mapping
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204 | LibLocale locale.h Localization types, macros, and functions
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205 | LibMath math.h Mathematical functions, types, and macros
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206 | LibStdio stdio.h Standard Input and Output functions, types, and
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207 | macros
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208 | LibStdLib stdlib.h General Utilities for numeric conversion, random
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209 | num., etc.
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210 | LibString string.h String copying, concatenation, comparison,
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211 | & search
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212 | LibSignal signal.h Functions and types for handling run-time
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213 | conditions
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214 | LibTime time.h Time and Date types, macros, and functions
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215 | LibUefi sys/EfiSysCall.h Provides the UEFI system interface and
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216 | "System Calls"
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217 | LibWchar wchar.h Extended multibyte and wide character utilities
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218 | LibNetUtil Network address and number manipulation utilities
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219 | DevConsole Automatically provided File I/O abstractions for
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220 | the UEFI Console device. No need to list this
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221 | library class in your INF file(s).
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222 | DevShell Add if desired File I/O abstractions using UEFI shell
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223 | facilities. Add this to the application's main
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224 | INF file if file-system access needed.
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225 | DevUtility -- Do Not Use -- Utility functions used internally by the Device abstractions
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226 | LibGdtoa -- Do Not Use -- This library is used internally and should not
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227 | need to be explicitly specified by an
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228 | application. It must be defined as one of the
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229 | available library classes in the application's
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230 | DSC file.
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231 |
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232 | Table 1: Standard Libraries
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233 | ============================
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234 |
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235 | The DevConsole and DevShell libraries provide device I/O functionality and are treated
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236 | specially. DevConsole is automatically included so there is no need to reference it in your
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237 | application's DSC or INF files. DevShell must be listed, in your application's INF file in the
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238 | [LibraryClasses] section, if your application does file I/O.
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239 |
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240 | These libraries must be fully described in the [LibraryClasses] section of the
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241 | application package's DSC file. Then, each individual application needs to
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242 | specify which libraries to link to by specifying the Library Class, from the
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243 | above table, in the [LibraryClasses] section of the application's INF file. The
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244 | AppPkg.dsc, StdLib.dsc, and Enquire.inf files provide good examples of this.
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245 | More details are in the CONFIGURATION section, below.
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246 |
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247 | In order to simplify this process, the [LibraryClasses] definitions, and others, are
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248 | specified in the StdLib.inc file. If this file is included in the DSC file, usually at the
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249 | end, then other DSC file changes or additions are unnecessary. This is further described in
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250 | the CONFIGURATION section, below.
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251 |
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252 | Within the source files of the application, use of the Standard headers and
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253 | library functions follow standard C programming practices as formalized by
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254 | ISO/IEC 9899:1990, with Addendum 1, (C 95) C language specification.
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255 |
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256 |
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257 | BUILD CONFIGURATION
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258 | ===================
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259 | DSC Files
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260 | ---------
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261 |
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262 | All EDK II packages which build applications that use the standard libraries
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263 | must include some "boilerplate" text in the package's .dsc file. To make it
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264 | easier, and to reduce cut-and-paste errors, the "boilerplate" text has been
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265 | consolidated into a single file, StdLib/StdLib.inc, which can be included in
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266 | your .dsc file using the !include directive. The provided AppPkg.dsc and
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267 | StdLib.dsc files do this on their last line.
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268 |
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269 | The "boilerplate" text can be included using a !include directive in the
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270 | package's .dsc file. The provided AppPkg.dsc and StdLib.dsc files include
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271 | the following "boilerplate" text:
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272 |
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273 | ##############################################################################
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274 | #
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275 | # Specify whether we are running in an emulation environment, or not.
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276 | # Define EMULATE if we are, else keep the DEFINE commented out.
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277 | #
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278 | # DEFINE EMULATE = 1
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279 |
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280 | ##############################################################################
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281 | #
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282 | # Include Boilerplate text required for building with the Standard Libraries.
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283 | #
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284 | ##############################################################################
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285 | !include StdLib/StdLib.inc
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286 |
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287 | Figure 1: "Boilerplate" Inclusion
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288 | =================================
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289 |
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290 | The EMULATE macro must be defined if one desires to do source-level debugging within one of
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291 | the emulated environments such as NT32Pkg or UnixPkg.
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292 |
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293 | The final boilerplate line, in Figure 1, includes the StdLib.inc file.
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294 | Each section of StdLib/StdLib.inc is described below.
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295 |
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296 | If desired, all of the Socket applications, in AppPkg, can be built by including Sockets.inc:
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297 |
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298 | !include AppPkg/Applications/Sockets/Sockets.inc
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299 |
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300 | Figure 2: Socket Applications "Boilerplate" Inclusion
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301 | =====================================================
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302 |
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303 |
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304 | Descriptions of the Library Classes comprising the Standard Libraries,
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305 | as shown in Figure 3: Library Class Descriptions, are provided.
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306 |
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307 | [LibraryClasses]
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308 | #
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309 | # C Standard Libraries
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310 | #
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311 | LibC|StdLib/LibC/LibC.inf
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312 | LibCType|StdLib/LibC/Ctype/Ctype.inf
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313 | LibLocale|StdLib/LibC/Locale/Locale.inf
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314 | LibMath|StdLib/LibC/Math/Math.inf
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315 | LibSignal|StdLib/LibC/Signal/Signal.inf
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316 | LibStdio|StdLib/LibC/Stdio/Stdio.inf
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317 | LibStdLib|StdLib/LibC/StdLib/StdLib.inf
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318 | LibString|StdLib/LibC/String/String.inf
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319 | LibTime|StdLib/LibC/Time/Time.inf
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320 | LibUefi|StdLib/LibC/Uefi/Uefi.inf
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321 | LibWchar|StdLib/LibC/Wchar/Wchar.inf
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322 |
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323 | # Common Utilities for Networking Libraries
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324 | LibNetUtil|StdLib/LibC/NetUtil/NetUtil.inf
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325 |
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326 | # Additional libraries for POSIX functionality.
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327 | LibErr|StdLib/PosixLib/Err/LibErr.inf
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328 | LibGen|StdLib/PosixLib/Gen/LibGen.inf
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329 | LibGlob|StdLib/PosixLib/Glob/LibGlob.inf
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330 | LibStringlist|StdLib/PosixLib/Stringlist/LibStringlist.inf
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331 |
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332 | # Libraries for device abstractions within the Standard C Library
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333 | # Applications should not directly access any functions defined in these libraries.
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334 | LibGdtoa|StdLib/LibC/gdtoa/gdtoa.inf
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335 | DevConsole|StdLib/LibC/Uefi/Devices/daConsole.inf
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336 | DevShell|StdLib/LibC/Uefi/Devices/daShell.inf
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337 | DevUtility|StdLib/LibC/Uefi/Devices/daUtility.inf
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338 |
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339 | [LibraryClasses.ARM.UEFI_APPLICATION]
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340 | NULL|ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf
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341 |
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342 | Figure 3: Library Class Descriptions
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343 | ====================================
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344 |
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345 |
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346 | The directives in Figure 4: Package Component Descriptions will create
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347 | instances of the BaseLib and BaseMemoryLib library classes that are built
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348 | with Link-time-Code-Generation disabled. This is necessary when using the
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349 | Microsoft tool chains in order to allow the library's functions to be
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350 | resolved during the second pass of the linker during Link-Time-Code-Generation
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351 | of the application.
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352 |
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353 | A DXE driver version of the Socket library is also built.
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354 |
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355 | [Components]
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356 | # BaseLib and BaseMemoryLib need to be built with the /GL- switch
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357 | # when using the Microsoft tool chains. This is required so that
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358 | # the library functions can be resolved during the second pass of
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359 | # the linker during link-time-code-generation.
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360 | #
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361 | MdePkg/Library/BaseLib/BaseLib.inf {
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362 | <BuildOptions>
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363 | MSFT:*_*_*_CC_FLAGS = /X /Zc:wchar_t /GL-
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364 | }
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365 | MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf {
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366 | <BuildOptions>
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367 | MSFT:*_*_*_CC_FLAGS = /X /Zc:wchar_t /GL-
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368 | }
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369 |
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370 | ##########
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371 | # Socket Layer
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372 | ##########
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373 | StdLib/SocketDxe/SocketDxe.inf
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374 |
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375 | Figure 4: Package Component Descriptions
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376 | ========================================
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377 |
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378 |
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379 | Each compiler assumes, by default, that it will be used with standard libraries
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380 | and headers provided by the compiler vendor. Many of these assumptions are
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381 | incorrect for the UEFI environment. By including a BuildOptions section, as
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382 | shown in Figure 5: Package Build Options, these assumptions can be
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383 | tailored for compatibility with UEFI and the EDK II Standard Libraries.
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384 |
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385 | Note that the set of BuildOptions used is determined by the state of the EMULATE macro.
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386 |
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387 | [BuildOptions]
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388 | !ifndef $(EMULATE)
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389 | # These Build Options are used when building the Standard Libraries to be run
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390 | # on real hardware.
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391 | INTEL:*_*_IA32_CC_FLAGS = /Qfreestanding
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392 | MSFT:*_*_IA32_CC_FLAGS = /X /Zc:wchar_t
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393 | GCC:*_*_IA32_CC_FLAGS = -nostdinc -nostdlib
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394 |
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395 | !else
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396 | # The Build Options, below, are only used when building the Standard Libraries
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397 | # to be run under an emulation environment.
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398 | # They disable optimization which facillitates debugging under the Emulation environment.
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399 | INTEL:*_*_IA32_CC_FLAGS = /Od
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400 | MSFT:*_*_IA32_CC_FLAGS = /Od
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401 | GCC:*_*_IA32_CC_FLAGS = -O0
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402 |
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403 | Figure 5: Package Build Options
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404 | ===============================
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405 |
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406 |
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407 | INF Files
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408 | =========
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409 | The INF files for most modules will not require special directives in order to
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410 | support the Standard Libraries. The two sections which require attention: LibraryClasses
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411 | and BuildOptions, are described below.
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412 |
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413 | [LibraryClasses]
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414 | UefiLib
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415 | LibC
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416 | LibString
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417 | LibStdio
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418 | DevShell
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419 |
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420 | Figure 6: Module Library Classes
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421 | ================================
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422 |
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423 |
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424 | Modules of type UEFI_APPLICATION that perform file I/O must include library
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425 | class DevShell. Including this library class will allow file operations to be
|
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426 | handled by the UEFI Shell. Without this class, only Console I/O is supported.
|
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427 |
|
---|
428 |
|
---|
429 | An application's INF file might need to include a [BuildOptions] section
|
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430 | specifying additional compiler and linker flags necessary to allow the
|
---|
431 | application to be built. Usually, this section is not needed. When building
|
---|
432 | code from external sources, though, it may be necessary to disable some
|
---|
433 | warnings or enable/disable some compiler features.
|
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434 |
|
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435 | [BuildOptions]
|
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436 | INTEL:*_*_*_CC_FLAGS = /Qdiag-disable:181,186
|
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437 | MSFT:*_*_*_CC_FLAGS = /Oi- /wd4018 /wd4131
|
---|
438 | GCC:*_*_IPF_SYMRENAME_FLAGS = --redefine-syms=Rename.txt
|
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439 |
|
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440 | Figure 7: Module Build Options
|
---|
441 | ==============================
|
---|
442 |
|
---|
443 |
|
---|
444 | TARGET-SYSTEM INSTALLATION
|
---|
445 | ==========================
|
---|
446 | Applications that use file system features or the Socket library depend upon
|
---|
447 | the existence of a specific directory tree structure on the same volume that
|
---|
448 | the application was loaded from. This tree structure is described below:
|
---|
449 |
|
---|
450 | /EFI Root of the UEFI system area.
|
---|
451 | |- /Tools Directory containing applications.
|
---|
452 | |- /Boot UEFI specified Boot directory.
|
---|
453 | |- /StdLib Root of the Standard Libraries sub-tree.
|
---|
454 | |- /etc Configuration files used by libraries.
|
---|
455 | |- /tmp Temporary files created by tmpfile(), etc.
|
---|
456 |
|
---|
457 |
|
---|
458 | The /Efi/StdLib/etc directory must be manually populated from the StdLib/Efi/etc source
|
---|
459 | directory.
|
---|
460 |
|
---|
461 | IMPLEMENTATION-Specific Features
|
---|
462 | ================================
|
---|
463 | It is very strongly recommended that applications not use the long or
|
---|
464 | unsigned long types. The size of these types varies between compilers and is one
|
---|
465 | of the less portable aspects of C. Instead, one should use the UEFI defined
|
---|
466 | types whenever possible. Use of these types, listed below for reference,
|
---|
467 | ensures that the declared objects have unambiguous, explicitly declared, sizes
|
---|
468 | and characteristics.
|
---|
469 |
|
---|
470 | UINT64 INT64 UINT32 INT32 UINT16 CHAR16
|
---|
471 | INT16 BOOLEAN UINT8 CHAR8 INT8
|
---|
472 | UINTN INTN PHYSICALADDRESS
|
---|
473 |
|
---|
474 | There are similar types declared in sys/types.h and related files.
|
---|
475 |
|
---|
476 | The types UINTN and INTN have the native width of the target processor
|
---|
477 | architecture. Thus, INTN on IA32 has a width of 32 bits while INTN on X64 and
|
---|
478 | IPF has a width of 64 bits.
|
---|
479 |
|
---|
480 | For maximum portability, data objects intended to hold addresses should be
|
---|
481 | declared with type intptr_t or uintptr_t. These types, declared in
|
---|
482 | sys/stdint.h, can be used to create objects capable of holding pointers. Note
|
---|
483 | that these types will generate different sized objects on different processor
|
---|
484 | architectures. If a constant size across all processors and compilers is
|
---|
485 | needed, use type PHYSICAL_ADDRESS.
|
---|
486 |
|
---|
487 | Though not specifically required by the ISO/IEC 9899 standard, this
|
---|
488 | implementation of the Standard C Library provides the following system calls
|
---|
489 | which are declared in sys/EfiSysCall.h and/or unistd.h.
|
---|
490 |
|
---|
491 | close creat chmod dup dup2
|
---|
492 | fcntl fstat getcwd ioctl isatty
|
---|
493 | lseek lstat mkdir open poll
|
---|
494 | read rename rmdir stat unlink write
|
---|
495 |
|
---|
496 | The open function will accept file names of "stdin:", "stdout:", and "stderr:"
|
---|
497 | which cause the respective streams specified in the UEFI System Table to be
|
---|
498 | opened. Normally, these are associated with the console device. When the
|
---|
499 | application is first started, these streams are automatically opened on File
|
---|
500 | Descriptors 0, 1, and 2 respectively.
|
---|
501 |
|
---|
502 | # # #
|
---|