lib/cmdline.c

   1 #include "lib.h"
   2
   3 #include "efiprot.h"
   4 #include "efishellintf.h"
   5 #include "efishellparm.h"
   6
   7 #ifndef MAX_ARGV_CONTENTS_SIZE
   8 # define MAX_CMDLINE_SIZE 1024
   9 #endif
  10 #ifndef MAX_ARGC
  11 # define MAX_CMDLINE_ARGC 32
  12 #endif
  13
  14 /*
  15   Parse LoadedImage options area, called only in case the regular
  16   shell protos are not available.
  17
  18   Format of LoadedImage->LoadOptions appears to be a
  19   single-space-separated list of args (looks like the shell already
  20   pre-parses the input, it apparently folds several consecutive spaces
  21   into one):
  22     argv[0] space argv[1] (etc.) argv[N] space \0 cwd \0 other data
  23   For safety, we support the trailing \0 without a space before, as
  24   well as several consecutive spaces (-> several args).
  25 */
  26 static
  27 INTN
  28 GetShellArgcArgvFromLoadedImage(
  29     EFI_HANDLE ImageHandle,
  30     CHAR16 **ResultArgv[]
  31     )
  32 {
  33   EFI_STATUS Status;
  34   void *LoadedImage = NULL;
  35   static CHAR16 ArgvContents[MAX_CMDLINE_SIZE];
  36   static CHAR16 *Argv[MAX_CMDLINE_ARGC], *ArgStart, *c;
  37   UINTN Argc = 0, BufLen;
  38
  39   Status = uefi_call_wrapper(BS->OpenProtocol, 6,
  40                              ImageHandle,
  41                              &LoadedImageProtocol,
  42                              &LoadedImage,
  43                              ImageHandle,
  44                              NULL,
  45                              EFI_OPEN_PROTOCOL_GET_PROTOCOL
  46                              );
  47   if (EFI_ERROR(Status))
  48     return -1;
  49
  50   BufLen = ((EFI_LOADED_IMAGE *)LoadedImage)->LoadOptionsSize;
  51   if (BufLen < 2)  /* We are expecting at least a \0 */
  52     return -1;
  53   else if (BufLen > sizeof(ArgvContents))
  54     BufLen = sizeof(ArgvContents);
  55
  56   CopyMem(ArgvContents, ((EFI_LOADED_IMAGE *)LoadedImage)->LoadOptions, BufLen);
  57   ArgvContents[MAX_CMDLINE_SIZE - 1] = L'\0';
  58
  59   for (c = ArgStart = ArgvContents ; *c != L'\0' ; ++c) {
  60     if (*c == L' ') {
  61       *c = L'\0';
  62       if (Argc < MAX_CMDLINE_ARGC) Argv[Argc++] = ArgStart;
  63       ArgStart = c + 1;
  64     }
  65   }
  66
  67   if ((*ArgStart != L'\0') && (Argc < MAX_CMDLINE_ARGC))
  68     Argv[Argc++] = ArgStart;
  69
  70   // Print(L"Got argc/argv from loaded image proto\n");
  71   *ResultArgv = Argv;
  72   return Argc;
  73 }
  74
  75 INTN GetShellArgcArgv(EFI_HANDLE ImageHandle, CHAR16 **Argv[])
  76 {
  77   // Code inspired from EDK2's
  78   // ShellPkg/Library/UefiShellCEntryLib/UefiShellCEntryLib.c (BSD)
  79   EFI_STATUS Status;
  80   static const EFI_GUID EfiShellParametersProtocolGuid
  81       = EFI_SHELL_PARAMETERS_PROTOCOL_GUID;
  82   static const EFI_GUID ShellInterfaceProtocolGuid
  83       = SHELL_INTERFACE_PROTOCOL_GUID;
  84   EFI_SHELL_PARAMETERS_PROTOCOL *EfiShellParametersProtocol = NULL;
  85   EFI_SHELL_INTERFACE *EfiShellInterfaceProtocol = NULL;
  86
  87   Status = uefi_call_wrapper(BS->OpenProtocol, 6,
  88                              ImageHandle,
  89                              (EFI_GUID*)&EfiShellParametersProtocolGuid,
  90                              (VOID **)&EfiShellParametersProtocol,
  91                              ImageHandle,
  92                              NULL,
  93                              EFI_OPEN_PROTOCOL_GET_PROTOCOL
  94                              );
  95   if (!EFI_ERROR(Status))
  96   {
  97     // use shell 2.0 interface
  98     // Print(L"Got argc/argv from shell intf proto\n");
  99     *Argv = EfiShellParametersProtocol->Argv;
 100     return EfiShellParametersProtocol->Argc;
 101   }
 102
 103   // try to get shell 1.0 interface instead.
 104   Status = uefi_call_wrapper(BS->OpenProtocol, 6,
 105                              ImageHandle,
 106                              (EFI_GUID*)&ShellInterfaceProtocolGuid,
 107                              (VOID **)&EfiShellInterfaceProtocol,
 108                              ImageHandle,
 109                              NULL,
 110                              EFI_OPEN_PROTOCOL_GET_PROTOCOL
 111                              );
 112   if (!EFI_ERROR(Status))
 113   {
 114     // Print(L"Got argc/argv from shell params proto\n");
 115     *Argv = EfiShellInterfaceProtocol->Argv;
 116     return EfiShellInterfaceProtocol->Argc;
 117   }
 118
 119   // shell 1.0 and 2.0 interfaces failed
 120   return GetShellArgcArgvFromLoadedImage(ImageHandle, Argv);
 121 }