EmbeddedPkg/EblExternCmd/EntryPointGlue.c

   1 /** @file
   2   Glue code that contains the EFI entry point and converts it to an EBL
   3   ASCII Argc, Argv sytle entry point
   4
   5
   6   Copyright (c) 2007, Intel Corporation. All rights reserved.<BR>
   7   Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   8
   9   This program and the accompanying materials
  10   are licensed and made available under the terms and conditions of the BSD License
  11   which accompanies this distribution.  The full text of the license may be found at
  12   http://opensource.org/licenses/bsd-license.php
  13
  14   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  15   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  16
  17
  18 **/
  19
  20 #define CMD_SEPARATOR     ';'
  21 #define MAX_ARGS          32
  22
  23 EFI_STATUS
  24 EblMain (
  25   IN UINTN  Argc,
  26   IN CHAR8  **Argv
  27   );
  28
  29
  30 ///
  31 /// EdkExternCmdEntry() & ParseArguments() convert the standard EFI entry point
  32 /// into Argc, Argv form that calls EblMain().
  33 ///
  34
  35
  36 /**
  37   Parse the CmdLine and break it up into Argc (arg count) and Argv (array of
  38   pointers to each argument). The Cmd buffer is altered and separators are
  39   converted to string terminators. This allows Argv to point into CmdLine.
  40   A CmdLine can support multiple commands. The next command in the command line
  41   is returned if it exists.
  42
  43   @param  CmdLine     String to parse for a set of commands
  44   @param  CmdLineSize Size of CmdLine in bytes
  45   @param  Argc        Returns the number of arguments in the CmdLine current command
  46   @param  Argv        Argc pointers to each string in CmdLine
  47
  48   @return Next Command in the command line or NULL if non exists
  49 **/
  50 VOID
  51 ParseArguments (
  52   IN  CHAR8  *CmdLine,
  53   IN  UINTN  CmdLineSize,
  54   OUT UINTN  *Argc,
  55   OUT CHAR8  **Argv
  56   )
  57 {
  58   UINTN   Arg;
  59   CHAR8   *Char;
  60   BOOLEAN LookingForArg;
  61   BOOLEAN InQuote;
  62   UINTN   Index;
  63
  64   *Argc = 0;
  65   if ((CmdLineSize == 0) || (AsciiStrLen (CmdLine) == 0)) {
  66     // basic error checking failed on the arguments
  67     return;
  68   }
  69
  70   // Walk a single command line. A CMD_SEPARATOR allows multiple commands on a single line
  71   InQuote       = FALSE;
  72   LookingForArg = TRUE;
  73   for (Char = CmdLine, Arg = 0, Index = 0; *Char != '\0' && *Char != CMD_SEPARATOR; Char++, Index++) {
  74     // Perform any text conversion here
  75     if (*Char == '\t') {
  76       // TAB to space
  77       *Char = ' ';
  78     }
  79
  80     if (LookingForArg) {
  81       // Look for the beginning of an Argv[] entry
  82       if (*Char == '"') {
  83         Argv[Arg++] = ++Char;
  84         LookingForArg = FALSE;
  85         InQuote = TRUE;
  86       } else if (*Char != ' ') {
  87         Argv[Arg++] = Char;
  88         LookingForArg = FALSE;
  89       }
  90     } else {
  91       // Looking for the terminator of an Argv[] entry
  92       if ((InQuote && (*Char == '"')) || (!InQuote && (*Char == ' '))) {
  93         *Char = '\0';
  94         LookingForArg = TRUE;
  95       }
  96     }
  97
  98     if ((Arg >= MAX_ARGS) || (Index > CmdLineSize)) {
  99       // Error check buffer and exit since it does not look valid
 100       break;
 101     }
 102   }
 103
 104   *Argc = Arg;
 105
 106   if (*Char == CMD_SEPARATOR) {
 107     // Replace the command delimiter with null
 108     *Char = '\0';
 109   }
 110
 111   return;
 112 }
 113
 114
 115
 116
 117 /**
 118   Embedded Boot Loader (EBL) - A simple EFI command line application for embedded
 119   devices. PcdEmbeddedAutomaticBootCommand is a complied in command line that
 120   gets executed automatically. The ; separator allows multiple commands
 121   for each command line.
 122
 123   @param  ImageHandle   EFI ImageHandle for this application.
 124   @param  SystemTable   EFI system table
 125
 126   @return EFI status of the application
 127
 128 **/
 129 EFI_STATUS
 130 EFIAPI
 131 EdkExternCmdEntry (
 132   IN EFI_HANDLE                            ImageHandle,
 133   IN EFI_SYSTEM_TABLE                      *SystemTable
 134   )
 135 {
 136   EFI_STATUS                  Status;
 137   EFI_LOADED_IMAGE_PROTOCOL   *ImageInfo;
 138   UINTN                       Argc;
 139   CHAR8                       *Argv[MAX_ARGS];
 140
 141   Status = gBS->HandleProtocol (ImageHandle, &gEfiLoadedImageProtocolGuid, (VOID **)&ImageInfo);
 142   if (EFI_ERROR (Status)) {
 143     Argc = 0;
 144   } else {
 145     // Looks like valid commands were passed in.
 146     ParseArguments (ImageInfo->LoadOptions, ImageInfo->LoadOptionsSize, &Argc, Argv);
 147   }
 148
 149   return EblMain (Argc, Argv);
 150 }
 151
 152