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 #include "Ebl.h"
  21
  22 #define CMD_SEPARATOR     ';'
  23 #define MAX_ARGS          32
  24
  25 EFI_STATUS
  26 EblMain (
  27   IN UINTN  Argc,
  28   IN CHAR8  **Argv
  29   );
  30
  31
  32 ///
  33 /// EdkExternCmdEntry() & ParseArguments() convert the standard EFI entry point
  34 /// into Argc, Argv form that calls EblMain().
  35 ///
  36
  37
  38 /**
  39   Parse the CmdLine and break it up into Argc (arg count) and Argv (array of
  40   pointers to each argument). The Cmd buffer is altered and separators are
  41   converted to string terminators. This allows Argv to point into CmdLine.
  42   A CmdLine can support multiple commands. The next command in the command line
  43   is returned if it exists.
  44
  45   @param  CmdLine     String to parse for a set of commands
  46   @param  CmdLineSize Size of CmdLine in bytes
  47   @param  Argc        Returns the number of arguments in the CmdLine current command
  48   @param  Argv        Argc pointers to each string in CmdLine
  49
  50   @return Next Command in the command line or NULL if non exists
  51 **/
  52 VOID
  53 ParseArguments (
  54   IN  CHAR8  *CmdLine,
  55   IN  UINTN  CmdLineSize,
  56   OUT UINTN  *Argc,
  57   OUT CHAR8  **Argv
  58   )
  59 {
  60   UINTN   Arg;
  61   CHAR8   *Char;
  62   BOOLEAN LookingForArg;
  63   BOOLEAN InQuote;
  64   UINTN   Index;
  65
  66   *Argc = 0;
  67   if ((CmdLineSize == 0) || (AsciiStrLen (CmdLine) == 0)) {
  68     // basic error checking failed on the arguments
  69     return;
  70   }
  71
  72   // Walk a single command line. A CMD_SEPARATOR allows multiple commands on a single line
  73   InQuote       = FALSE;
  74   LookingForArg = TRUE;
  75   for (Char = CmdLine, Arg = 0, Index = 0; *Char != '\0' && *Char != CMD_SEPARATOR; Char++, Index++) {
  76     // Perform any text conversion here
  77     if (*Char == '\t') {
  78       // TAB to space
  79       *Char = ' ';
  80     }
  81
  82     if (LookingForArg) {
  83       // Look for the beginning of an Argv[] entry
  84       if (*Char == '"') {
  85         Argv[Arg++] = ++Char;
  86         LookingForArg = FALSE;
  87         InQuote = TRUE;
  88       } else if (*Char != ' ') {
  89         Argv[Arg++] = Char;
  90         LookingForArg = FALSE;
  91       }
  92     } else {
  93       // Looking for the terminator of an Argv[] entry
  94       if ((InQuote && (*Char == '"')) || (!InQuote && (*Char == ' '))) {
  95         *Char = '\0';
  96         LookingForArg = TRUE;
  97       }
  98     }
  99
 100     if ((Arg >= MAX_ARGS) || (Index > CmdLineSize)) {
 101       // Error check buffer and exit since it does not look valid
 102       break;
 103     }
 104   }
 105
 106   *Argc = Arg;
 107
 108   if (*Char == CMD_SEPARATOR) {
 109     // Replace the command delimiter with null
 110     *Char = '\0';
 111   }
 112
 113   return;
 114 }
 115
 116
 117
 118
 119 /**
 120   Embedded Boot Loader (EBL) - A simple EFI command line application for embedded
 121   devices. PcdEmbeddedAutomaticBootCommand is a complied in command line that
 122   gets executed automatically. The ; separator allows multiple commands
 123   for each command line.
 124
 125   @param  ImageHandle   EFI ImageHandle for this application.
 126   @param  SystemTable   EFI system table
 127
 128   @return EFI status of the application
 129
 130 **/
 131 EFI_STATUS
 132 EFIAPI
 133 EdkExternCmdEntry (
 134   IN EFI_HANDLE                            ImageHandle,
 135   IN EFI_SYSTEM_TABLE                      *SystemTable
 136   )
 137 {
 138   EFI_STATUS                  Status;
 139   EFI_LOADED_IMAGE_PROTOCOL   *ImageInfo;
 140   UINTN                       Argc;
 141   CHAR8                       *Argv[MAX_ARGS];
 142
 143   Status = gBS->HandleProtocol (ImageHandle, &gEfiLoadedImageProtocolGuid, (VOID **)&ImageInfo);
 144   if (EFI_ERROR (Status)) {
 145     Argc = 0;
 146   } else {
 147     // Looks like valid commands were passed in.
 148     ParseArguments (ImageInfo->LoadOptions, ImageInfo->LoadOptionsSize, &Argc, Argv);
 149   }
 150
 151   return EblMain (Argc, Argv);
 152 }
 153
 154