StdLib: Fix IIO_Write() to return the number of bytes consumed, not characters output.

[mirror_edk2.git] / StdLib / LibC / Uefi / SysCalls.c

/** @file\r
  EFI versions of NetBSD system calls.\r
\r
  Copyright (c) 2016, Daryl McDaniel. All rights reserved.<BR>\r
  Copyright (c) 2010 - 2012, Intel Corporation. All rights reserved.<BR>\r
  This program and the accompanying materials are licensed and made available under\r
  the terms and conditions of the BSD License that accompanies this distribution.\r
  The full text of the license may be found at\r
  http://opensource.org/licenses/bsd-license.\r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
#include  <Uefi.h>\r
#include  <Library/UefiLib.h>\r
#include  <Library/UefiBootServicesTableLib.h>\r
#include  <Library/BaseLib.h>\r
#include  <Library/MemoryAllocationLib.h>\r
#include  <Library/ShellLib.h>\r
\r
#include  <LibConfig.h>\r
#include  <sys/EfiCdefs.h>\r
\r
#include  <sys/ansi.h>\r
#include  <errno.h>\r
#include  <stdarg.h>\r
#include  <stdlib.h>\r
#include  <string.h>\r
#include  <wchar.h>\r
#include  <sys/poll.h>\r
#include  <sys/fcntl.h>\r
#include  <sys/stat.h>\r
#include  <sys/syslimits.h>\r
#include  <sys/filio.h>\r
#include  <Efi/SysEfi.h>\r
#include  <unistd.h>\r
#include  <kfile.h>\r
#include  <Device/Device.h>\r
#include  <Device/IIO.h>\r
#include  <MainData.h>\r
#include  <extern.h>\r
\r
/* EFI versions of BSD system calls used in stdio */\r
\r
/*  Validate that fd refers to a valid file descriptor.\r
    IsOpen is interpreted as follows:\r
      - Positive  fd must be OPEN\r
      - Zero      fd must be CLOSED\r
      - Negative  fd may be OPEN or CLOSED\r
\r
    @retval TRUE  fd is VALID\r
    @retval FALSE fd is INVALID\r
*/\r
BOOLEAN\r
ValidateFD( int fd, int IsOpen)\r
{\r
  struct __filedes    *filp;\r
  BOOLEAN   retval = FALSE;\r
\r
  if((fd >= 0) && (fd < OPEN_MAX)) {\r
    filp = &gMD->fdarray[fd];\r
    retval = TRUE;\r
    if(IsOpen >= 0) {\r
      retval = (BOOLEAN)((filp->f_iflags != 0)  &&    // TRUE if OPEN\r
                         FILE_IS_USABLE(filp));         // and Usable (not Larval or Closing)\r
      if(IsOpen == VALID_CLOSED) {\r
        retval = (BOOLEAN)!retval;                      // We want TRUE if CLOSED\r
      }\r
    }\r
  }\r
  return retval;\r
}\r
\r
/* Find and reserve a free File Descriptor.\r
\r
  Returns the first free File Descriptor greater than or equal to the,\r
  already validated, fd specified by Minfd.\r
\r
  @return   Returns -1 if there are no free FDs.  Otherwise returns the\r
            found fd.\r
*/\r
int\r
FindFreeFD( int MinFd )\r
{\r
  struct __filedes    *Mfd;\r
  int i;\r
  int fd = -1;\r
\r
  Mfd = gMD->fdarray;\r
\r
  // Get an available fd\r
  for(i=MinFd; i < OPEN_MAX; ++i) {\r
    if(Mfd[i].f_iflags == 0) {\r
      Mfd[i].f_iflags = FIF_LARVAL; // Temporarily mark this fd as reserved\r
      fd = i;\r
      break;\r
    }\r
  }\r
  return fd;\r
}\r
\r
/* Mark that an open file is to be deleted when closed. */\r
int\r
DeleteOnClose(int fd)\r
{\r
  int   retval = 0;\r
\r
  if(ValidateFD( fd, VALID_OPEN)) {\r
    gMD->fdarray[fd].f_iflags |= FIF_DELCLOSE;\r
  }\r
  else {\r
    errno = EBADF;\r
    retval = -1;\r
  }\r
  return retval;\r
}\r
\r
/** The isatty() function tests whether fd, an open file descriptor,\r
    is associated with a terminal device.\r
\r
    @param[in]  fd  File Descriptor for the file to be examined.\r
\r
    @retval   1   fd is associated with a terminal.\r
    @retval   0   fd is not associated with a terminal.  errno is set to\r
                  EBADF if fd is not a valid open FD.\r
**/\r
int\r
isatty  (int fd)\r
{\r
  int   retval = 0;\r
  struct __filedes *Fp;\r
\r
  if(ValidateFD( fd, VALID_OPEN)) {\r
    Fp = &gMD->fdarray[fd];\r
    retval =  (Fp->f_iflags & _S_ITTY) ? 1 : 0;\r
  }\r
  else {\r
    errno = EBADF;\r
  }\r
  return retval;\r
}\r
\r
/** Determine if file descriptor fd is a duplicate of some other fd.\r
\r
    @param[in]    fd    The file descriptor to check.\r
\r
    @retval   TRUE    fd is a duplicate of another fd.\r
    @retval   FALSE   fd is unique.\r
**/\r
static BOOLEAN\r
IsDupFd( int fd)\r
{\r
  void * DevData;\r
  const struct fileops   *FileOps;\r
  int                   i;\r
  BOOLEAN               Ret = FALSE;\r
\r
  if(ValidateFD( fd, VALID_OPEN )) {\r
    FileOps = gMD->fdarray[fd].f_ops;\r
    DevData = gMD->fdarray[fd].devdata;\r
    for(i=0; i < OPEN_MAX; ++i) {\r
      if(i == fd)   continue;\r
      if(ValidateFD( i, VALID_OPEN )) {   // TRUE if fd is valid and OPEN\r
        if((gMD->fdarray[i].f_ops == FileOps)\r
          &&(gMD->fdarray[i].devdata == DevData )) {\r
          Ret = TRUE;\r
          break;\r
        }\r
      }\r
    }\r
  }\r
  return Ret;\r
}\r
\r
/** Worker function to Close a file and set its fd to the specified state.\r
\r
    @param[in]    fd          The file descriptor to close.\r
    @param[in]    NewState    State to set the fd to after the file is closed.\r
\r
    @retval    0    The operation completed successfully.\r
    @retval   -1    The operation failed.  Further information is in errno.\r
                      * EBADF   fd is not a valid or open file descriptor.\r
**/\r
static int\r
_closeX  (int fd, int NewState)\r
{\r
  struct __filedes     *Fp;\r
  int                   retval = 0;\r
\r
  // Verify my pointers and get my FD.\r
  if(ValidateFD( fd, VALID_OPEN )) {\r
    Fp = &gMD->fdarray[fd];\r
    // Check if there are other users of this FileHandle\r
    if(Fp->RefCount == 1) { // There should be no other users\r
      if(! IsDupFd(fd)) {\r
        // Only do the close if no one else is using the FileHandle\r
        if(Fp->f_iflags & FIF_DELCLOSE) {\r
          /* Handle files marked "Delete on Close". */\r
          if(Fp->f_ops->fo_delete != NULL) {\r
            retval = Fp->f_ops->fo_delete(Fp);\r
          }\r
        }\r
        else {\r
          retval = Fp->f_ops->fo_close( Fp);\r
        }\r
      }\r
      Fp->f_iflags = NewState;    // Close this FD or reserve it\r
      Fp->RefCount = 0;           // No one using this FD\r
    }\r
    else {\r
      --Fp->RefCount;   /* One less user of this FD */\r
    }\r
  }\r
  else {\r
    // Bad FD\r
    retval = -1;\r
    errno = EBADF;\r
  }\r
  return retval;\r
}\r
\r
/** The close() function deallocates the file descriptor indicated by fd.\r
    To deallocate means to make the file descriptor available for return by\r
    subsequent calls to open() or other functions that allocate file\r
    descriptors. All outstanding record locks owned by the process on the file\r
    associated with the file descriptor are removed (that is, unlocked).\r
\r
    @param[in]    fd          Descriptor for the File to close.\r
\r
    @retval   0     Successful completion.\r
    @retval   -1    An error occurred and errno is set to identify the error.\r
**/\r
int\r
close  (int fd)\r
{\r
  return _closeX(fd, 0);\r
}\r
\r
/** Delete the file specified by path.\r
\r
    @param[in]    path  The MBCS path of the file to delete.\r
\r
    @retval   -1  Unable to open the file specified by path.\r
    @retval   -1  If (errno == EPERM), unlink is not permited for this file.\r
    @retval   -1  Low-level delete filed.  Reason is in errno.\r
    @retval   0   The file was successfully deleted.\r
**/\r
int\r
unlink (const char *path)\r
{\r
  struct __filedes     *Fp;\r
  int                   fd;\r
  int                   retval = -1;\r
\r
  EFIerrno = RETURN_SUCCESS;\r
\r
  fd = open(path, O_WRONLY, 0);\r
  if(fd >= 0) {\r
    Fp = &gMD->fdarray[fd];\r
\r
    if(Fp->f_ops->fo_delete != NULL) {\r
      retval = Fp->f_ops->fo_delete(Fp);\r
  }\r
    Fp->f_iflags = 0;    // Close this FD\r
    Fp->RefCount = 0;    // No one using this FD\r
  }\r
  return retval;\r
}\r
\r
/** The fcntl() function shall perform the operations described below on open\r
    files. The fildes argument is a file descriptor.\r
\r
    The available values for cmd are defined in <fcntl.h> and are as follows:\r
      - F_DUPFD - Return a new file descriptor which shall be the lowest\r
                  numbered available (that is, not already open) file\r
                  descriptor greater than or equal to the third argument, arg,\r
                  taken as an integer of type int. The new file descriptor\r
                  shall refer to the same open file description as the original\r
                  file descriptor, and shall share any locks. The FD_CLOEXEC\r
                  flag associated with the new file descriptor shall be cleared\r
                  to keep the file open across calls to one of the exec functions.\r
      - F_GETFD - Get the file descriptor flags defined in <fcntl.h> that are\r
                  associated with the file descriptor fildes. File descriptor\r
                  flags are associated with a single file descriptor and do not\r
                  affect other file descriptors that refer to the same file.\r
      - F_SETFD - Set the file descriptor flags defined in <fcntl.h>, that are\r
                  associated with fildes, to the third argument, arg, taken\r
                  as type int. If the FD_CLOEXEC flag in the third argument\r
                  is 0, the file shall remain open across the exec\r
                  functions; otherwise, the file shall be closed upon\r
                  successful execution of one of the exec functions.\r
      - F_GETFL - Get the file status flags and file access modes, defined in\r
                  <fcntl.h>, for the file description associated with fildes.\r
                  The file access modes can be extracted from the return\r
                  value using the mask O_ACCMODE, which is defined in\r
                  <fcntl.h>. File status flags and file access modes are\r
                  associated with the file description and do not affect\r
                  other file descriptors that refer to the same file with\r
                  different open file descriptions.\r
      - F_SETFL - Set the file status flags, defined in <fcntl.h>, for the file\r
                  description associated with fildes from the corresponding\r
                  bits in the third argument, arg, taken as type int. Bits\r
                  corresponding to the file access mode and the file creation\r
                  flags, as defined in <fcntl.h>, that are set in arg shall\r
                  be ignored. If any bits in arg other than those mentioned\r
                  here are changed by the application, the result is unspecified.\r
      - F_GETOWN -  If fildes refers to a socket, get the process or process group\r
                  ID specified to receive SIGURG signals when out-of-band\r
                  data is available. Positive values indicate a process ID;\r
                  negative values, other than -1, indicate a process group\r
                  ID. If fildes does not refer to a socket, the results are\r
                  unspecified.\r
      - F_SETOWN -  If fildes refers to a socket, set the process or process\r
                  group ID specified to receive SIGURG signals when\r
                  out-of-band data is available, using the value of the third\r
                  argument, arg, taken as type int. Positive values indicate\r
                  a process ID; negative values, other than -1, indicate a\r
                  process group ID. If fildes does not refer to a socket, the\r
                  results are unspecified.\r
\r
    The fcntl() function shall fail if:\r
\r
    [EBADF]       The fildes argument is not a valid open file descriptor.\r
    [EINVAL]      The cmd argument is invalid, or the cmd argument is F_DUPFD\r
                  and arg is negative or greater than or equal to {OPEN_MAX}.\r
    [EMFILE]      The argument cmd is F_DUPFD and {OPEN_MAX} file descriptors\r
                  are currently open in the calling process, or no file\r
                  descriptors greater than or equal to arg are available.\r
    [EOVERFLOW]   One of the values to be returned cannot be represented correctly.\r
\r
    @param[in]      fildes    Descriptor for the file to be controlled.\r
    @param[in]      cmd       Command to be acted upon.\r
    @param[in,out]  ...       Optional additional parameters as required by cmd.\r
\r
    @return   Upon successful completion, the value returned shall depend on\r
              cmd as follows:\r
                - F_DUPFD - A new file descriptor.\r
                - F_GETFD - Value of flags defined in <fcntl.h>. The return value\r
                            shall not be negative.\r
                - F_SETFD - Value other than -1.\r
                - F_GETFL - Value of file status flags and access modes. The return\r
                            value is not negative.\r
                - F_SETFL - Value other than -1.\r
                - F_GETOWN  - Value of the socket owner process or process group;\r
                            this will not be -1.\r
                - F_SETOWN - Value other than -1.\r
              Otherwise, -1 shall be returned and errno set to indicate the error.\r
\r
**/\r
int\r
fcntl     (int fildes, int cmd, ...)\r
{\r
  va_list             p3;\r
  struct __filedes   *MyFd;\r
  int                 retval = -1;\r
  int                 temp;\r
\r
//Print(L"%a( %d, %d, ...)\n", __func__, fildes, cmd);\r
  va_start(p3, cmd);\r
\r
  if(ValidateFD( fildes, VALID_OPEN )) {\r
    MyFd = &gMD->fdarray[fildes];\r
\r
    switch(cmd) {\r
      case F_DUPFD:\r
        temp = va_arg(p3, int);\r
        if(ValidateFD( temp, VALID_DONT_CARE )) {\r
          temp = FindFreeFD( temp );\r
          if(temp < 0) {\r
            errno = EMFILE;\r
            break;\r
          }\r
          /* temp is now a valid fd reserved for further use\r
             so copy fd into temp.\r
          */\r
          (void)memcpy(&gMD->fdarray[temp], MyFd, sizeof(struct __filedes));\r
          retval = temp;\r
        }\r
        else {\r
          errno = EINVAL;\r
        }\r
        break;\r
\r
      case F_SETFL:\r
        retval = MyFd->Oflags;        // Get original value\r
        temp = va_arg(p3, int);\r
        temp &= O_SETMASK;            // Only certain bits can be set\r
        temp |= retval & O_SETMASK;\r
        MyFd->Oflags = temp;          // Set new value\r
        break;\r
\r
      case F_SETFD:\r
        retval = MyFd->f_iflags;\r
        break;\r
      //case F_SETOWN:\r
      //  retval = MyFd->SocProc;\r
      //  MyFd->SocProc = va_arg(p3, int);\r
      //  break;\r
      case F_GETFD:\r
        retval = MyFd->f_iflags;\r
        break;\r
      case F_GETFL:\r
        retval = MyFd->Oflags;\r
        break;\r
      //case F_GETOWN:\r
      //  retval = MyFd->SocProc;\r
      //  break;\r
      default:\r
        errno  = EINVAL;\r
        break;\r
    }\r
  }\r
  else {\r
    // Bad FD\r
    errno = EBADF;\r
  }\r
  va_end(p3);\r
  return retval;;\r
}\r
\r
/** The dup() function provides an alternative interface to the\r
    service provided by fcntl() using the F_DUPFD command. The call:\r
      - fid = dup(fildes);\r
    shall be equivalent to:\r
      - fid = fcntl(fildes, F_DUPFD, 0);\r
\r
    @param[in]    fildes    Descriptor for the file to be examined.\r
\r
    @return   Upon successful completion a non-negative integer, namely the\r
              file descriptor, shall be returned; otherwise, -1 shall be\r
              returned and errno set to indicate the error.\r
**/\r
int\r
dup   (int fildes)\r
{\r
  return fcntl(fildes, F_DUPFD, 0);\r
}\r
\r
/** Make fildes2 refer to a duplicate of fildes.\r
\r
    The dup2() function provides an alternative interface to the\r
    service provided by fcntl() using the F_DUPFD command. The call:\r
      - fid = dup2(fildes, fildes2);\r
    shall be equivalent to:\r
      - close(fildes2);\r
      - fid = fcntl(fildes, F_DUPFD, fildes2);\r
    except for the following:\r
      - If fildes2 is less than 0 or greater than or equal to {OPEN_MAX},\r
        dup2() shall return -1 with errno set to [EBADF].\r
      - If fildes is a valid file descriptor and is equal to fildes2, dup2()\r
        shall return fildes2 without closing it.\r
      - If fildes is not a valid file descriptor, dup2() shall return -1 and\r
        shall not close fildes2.\r
      - The value returned shall be equal to the value of fildes2 upon\r
        successful completion, or -1 upon failure.\r
\r
    @param[in]  fildes    File Descriptor to be duplicated.\r
    @param[in]  fildes2   File Descriptor to be made a duplicate of fildes.\r
\r
    @return   Upon successful completion a non-negative integer, namely\r
              fildes2, shall be returned; otherwise, -1 shall be\r
              returned and errno set to EBADF indicate the error.\r
**/\r
int\r
dup2    (int fildes, int fildes2)\r
{\r
  int retval = -1;\r
\r
  if(ValidateFD( fildes, VALID_OPEN)) {\r
    retval = fildes2;\r
    if( fildes != fildes2) {\r
      if(ValidateFD( fildes2, VALID_DONT_CARE)) {\r
        gMD->fdarray[fildes2].f_iflags = FIF_LARVAL;  // Mark the file closed, but reserved\r
        (void)memcpy(&gMD->fdarray[fildes2],      // Duplicate fildes into fildes2\r
                     &gMD->fdarray[fildes], sizeof(struct __filedes));\r
        gMD->fdarray[fildes2].MyFD = (UINT16)fildes2;\r
      }\r
      else {\r
        errno = EBADF;\r
        retval = -1;\r
      }\r
    }\r
  }\r
  else {\r
    errno = EBADF;\r
  }\r
  return retval;\r
}\r
\r
/** Reposition a file's read/write offset.\r
\r
    The lseek() function repositions the offset of the file descriptor fildes\r
    to the argument offset according to the directive how.  The argument\r
    fildes must be an open file descriptor.  lseek() repositions the file\r
    pointer fildes as follows:\r
\r
      - If how is SEEK_SET, the offset is set to offset bytes.\r
\r
      - If how is SEEK_CUR, the offset is set to its current location\r
        plus offset bytes.\r
\r
      - If how is SEEK_END, the offset is set to the size of the file\r
        plus offset bytes.\r
\r
    The lseek() function allows the file offset to be set beyond the end of\r
    the existing end-of-file of the file.  If data is later written at this\r
    point, subsequent reads of the data in the gap return bytes of zeros\r
    (until data is actually written into the gap).\r
\r
    Some devices are incapable of seeking.  The value of the pointer associ-\r
    ated with such a device is undefined.\r
\r
    @param[in]  fd        Descriptor for the File to be affected.\r
    @param[in]  offset    Value to adjust the file position by.\r
    @param[in]  how       How the file position is to be adjusted.\r
\r
    @return   Upon successful completion, lseek() returns the resulting offset\r
              location as measured in bytes from the beginning of the file.\r
              Otherwise, a value of -1 is returned and errno is set to\r
              indicate the error.\r
**/\r
__off_t\r
lseek (int fd, __off_t offset, int how)\r
{\r
  __off_t             CurPos = -1;\r
//  RETURN_STATUS       Status = RETURN_SUCCESS;\r
  struct __filedes   *filp;\r
\r
  EFIerrno = RETURN_SUCCESS;    // In case of error without an EFI call\r
\r
  if( how == SEEK_SET || how == SEEK_CUR  || how == SEEK_END) {\r
    if(ValidateFD( fd, VALID_OPEN)) {\r
      filp = &gMD->fdarray[fd];\r
      // Both of our parameters have been verified as valid\r
      CurPos = filp->f_ops->fo_lseek( filp, offset, how);\r
      if(CurPos >= 0) {\r
        filp->f_offset = CurPos;\r
      }\r
    }\r
    else {\r
      errno = EBADF;  // Bad File Descriptor\r
    }\r
  }\r
  else {\r
    errno = EINVAL;   // Invalid how argument\r
  }\r
  return CurPos;\r
}\r
\r
/** The directory path is created with the access permissions specified by\r
    perms.\r
\r
    The directory is closed after it is created.\r
\r
    @param[in]  path    The path to a directory to create.\r
    @param[in]  perms   Permissions as defined in <sys/stat.h>\r
\r
    @retval   0   The directory was created successfully.\r
    @retval  -1   An error occurred and error codes are stored in errno and EFIerrno.\r
**/\r
int\r
mkdir (const char *path, __mode_t perms)\r
{\r
  wchar_t            *NewPath;\r
  DeviceNode         *Node;\r
  char               *GenI;\r
  RETURN_STATUS       Status;\r
  int                 Instance  = 0;\r
  int                 retval = 0;\r
\r
  Status = ParsePath(path, &NewPath, &Node, &Instance, NULL);\r
  if(Status == RETURN_SUCCESS) {\r
    GenI = Node->InstanceList;\r
    if(GenI == NULL) {\r
      errno   = EPERM;\r
      retval  = -1;\r
      }\r
    else {\r
      //GenI += (Instance * Node->InstanceSize);\r
      retval = ((GenericInstance *)GenI)->Abstraction.fo_mkdir( path, perms);\r
      }\r
    free(NewPath);\r
    }\r
  else {\r
    retval = -1;\r
  }\r
  return retval;\r
}\r
\r
/** Open a file.\r
    The open() function establishes the connection between a file and a file\r
    descriptor.  It creates an open file description that refers to a file\r
    and a file descriptor that refers to that open file description. The file\r
    descriptor is used by other I/O functions to refer to that file.\r
\r
    The open() function returns a file descriptor for the named file that is\r
    the lowest file descriptor not currently open for that process. The open\r
    file description is new, and therefore the file descriptor shall not\r
    share it with any other process in the system.\r
\r
    The file offset used to mark the current position within the file is set\r
    to the beginning of the file.\r
\r
    The EFI ShellOpenFileByName() function is used to perform the low-level\r
    file open operation.  The primary task of open() is to translate from the\r
    flags used in the <stdio.h> environment to those used by the EFI function.\r
\r
    The file status flags and file access modes of the open file description\r
    are set according to the value of oflags.\r
\r
    Values for oflags are constructed by a bitwise-inclusive OR of flags from\r
    the following list, defined in <fcntl.h>. Applications shall specify\r
    exactly one of { O_RDONLY, O_RDWR, O_WRONLY } in the value of oflags.\r
    Any combination of { O_NONBLOCK, O_APPEND, O_CREAT, O_TRUNC, O_EXCL } may\r
    also be specified in oflags.\r
\r
    The only valid flag combinations for ShellOpenFileByName() are:\r
      - Read\r
      - Read/Write\r
      - Create/Read/Write\r
\r
    Values for mode specify the access permissions for newly created files.\r
    The mode value is saved in the FD to indicate permissions for further operations.\r
\r
    O_RDONLY      -- flags = EFI_FILE_MODE_READ -- this is always done\r
    O_WRONLY      -- flags |= EFI_FILE_MODE_WRITE\r
    O_RDWR        -- flags |= EFI_FILE_MODE_WRITE -- READ is already set\r
\r
    O_NONBLOCK    -- ignored\r
    O_APPEND      -- Seek to EOF before every write\r
    O_CREAT       -- flags |= EFI_FILE_MODE_CREATE\r
    O_TRUNC       -- delete first then create new\r
    O_EXCL        -- if O_CREAT is also set, open will fail if the file already exists.\r
\r
    @param[in]    Path      The path argument points to a pathname naming the\r
                            object to be opened.\r
    @param[in]    oflags    File status flags and file access modes of the\r
                            open file description.\r
    @param[in]    mode      File access permission bits as defined in\r
                            <sys/stat.h>.  Only used if a file is created\r
                            as a result of the open.\r
\r
    @return     Upon successful completion, open() opens the file and returns\r
                a non-negative integer representing the lowest numbered\r
                unused file descriptor. Otherwise, open returns -1 and sets\r
                errno to indicate the error. If a negative value is\r
                returned, no files are created or modified.\r
                  - EMFILE - No file descriptors available -- Max number already open.\r
                  - EINVAL - Bad value specified for oflags or mode.\r
                  - ENOMEM - Failure allocating memory for internal buffers.\r
                  - EEXIST - File exists and open attempted with (O_EXCL | O_CREAT) set.\r
                  - EIO - UEFI failure.  Check value in EFIerrno.\r
**/\r
int\r
open(\r
  const char *path,\r
  int oflags,\r
  int mode\r
  )\r
{\r
  wchar_t              *NewPath;\r
  wchar_t              *MPath;\r
  DeviceNode           *Node;\r
  struct __filedes     *filp;\r
  struct termios       *Termio;\r
  int                   Instance  = 0;\r
  RETURN_STATUS         Status;\r
  UINT32                OpenMode;\r
  int                   fd = -1;\r
  int                   doresult;\r
\r
  Status = ParsePath(path, &NewPath, &Node, &Instance, &MPath);\r
  if(Status == RETURN_SUCCESS) {\r
    if ((Node == NULL)               ||\r
        (Node->InstanceList == NULL))\r
    {\r
      errno   = EPERM;\r
    }\r
    else {\r
      // Could add a test to see if the file name begins with a period.\r
      // If it does, then add the HIDDEN flag to Attributes.\r
\r
      // Get an available fd\r
      fd = FindFreeFD( VALID_CLOSED );\r
\r
      if( fd < 0 ) {\r
        // All available FDs are in use\r
        errno = EMFILE;\r
      }\r
      else {\r
        filp = &gMD->fdarray[fd];\r
        // Save the flags and mode in the File Descriptor\r
        filp->Oflags = oflags;\r
        filp->Omode = mode;\r
\r
        doresult = Node->OpenFunc(Node, filp, Instance, NewPath, MPath);\r
        if(doresult < 0) {\r
          filp->f_iflags = 0;   // Release this FD\r
          fd = -1;              // Indicate an error\r
        }\r
        else {\r
          // Build our final f_iflags value\r
          OpenMode  = ( mode & S_ACC_READ )  ? S_ACC_READ : 0;\r
          OpenMode |= ( mode & S_ACC_WRITE ) ? S_ACC_WRITE : 0;\r
\r
          filp->f_iflags |= OpenMode;\r
\r
          if((oflags & O_TTY_INIT) && (filp->f_iflags & _S_ITTY) && (filp->devdata != NULL)) {\r
            // Initialize the device's termios flags to a "sane" value\r
            Termio = &((cIIO *)filp->devdata)->Termio;\r
            Termio->c_iflag = ICRNL | IGNSPEC;\r
            Termio->c_oflag = OPOST | ONLCR | OXTABS | ONOEOT | ONOCR | ONLRET | OCTRL;\r
            Termio->c_lflag = ECHO | ECHOE | ECHONL | ICANON;\r
            Termio->c_cc[VERASE]  = 0x08;   // ^H Backspace\r
            Termio->c_cc[VKILL]   = 0x15;   // ^U\r
            Termio->c_cc[VINTR]   = 0x03;   // ^C Interrupt character\r
          }\r
          ++filp->RefCount;\r
          FILE_SET_MATURE(filp);\r
        }\r
      }\r
    }\r
    free(NewPath);\r
  }\r
  free(MPath);    // We don't need this any more.\r
\r
  // return the fd of our now open file\r
  return fd;\r
}\r
\r
\r
/**\r
  Poll a list of file descriptors.\r
\r
  The ::poll routine waits for up to timeout milliseconds for an event\r
  to occur on one or more of the file descriptors listed.  The event\r
  types of interested are specified for each file descriptor in the events\r
  field.  The actual event detected is returned in the revents field of\r
  the array.  The\r
  <a href="http://pubs.opengroup.org/onlinepubs/9699919799/functions/poll.html">POSIX</a>\r
  documentation is available online.\r
\r
  @param[in]  pfd       Address of an array of pollfd structures.\r
\r
  @param[in]  nfds      Number of elements in the array of pollfd structures.\r
\r
  @param[in]  timeout   Length of time in milliseconds to wait for the event\r
\r
  @return     The number of file descriptors with detected events.  Zero\r
              indicates that the call timed out and -1 indicates an error.\r
\r
 **/\r
int\r
poll (\r
  struct pollfd * pfd,\r
  nfds_t nfds,\r
  int timeout\r
  )\r
{\r
  struct __filedes * pDescriptor;\r
  struct pollfd * pEnd;\r
  struct pollfd * pPollFD;\r
  int SelectedFDs;\r
  EFI_STATUS Status;\r
  EFI_EVENT Timer;\r
  UINT64 TimerTicks;\r
\r
  //\r
  //  Create the timer for the timeout\r
  //\r
  Timer = NULL;\r
  Status = EFI_SUCCESS;\r
  if ( INFTIM != timeout ) {\r
    Status = gBS->CreateEvent ( EVT_TIMER,\r
                                TPL_NOTIFY,\r
                                NULL,\r
                                NULL,\r
                                &Timer );\r
    if ( !EFI_ERROR ( Status )) {\r
      //\r
      //  Start the timeout timer\r
      //\r
      TimerTicks = timeout;\r
      TimerTicks *= 1000 * 10;\r
      Status = gBS->SetTimer ( Timer,\r
                               TimerRelative,\r
                               TimerTicks );\r
    }\r
    else {\r
      SelectedFDs = -1;\r
      errno = ENOMEM;\r
    }\r
  }\r
  if ( !EFI_ERROR ( Status )) {\r
    //\r
    //  Poll until an event is detected or the timer fires\r
    //\r
    SelectedFDs = 0;\r
    errno = 0;\r
    do {\r
      //\r
      //  Poll the list of file descriptors\r
      //\r
      pPollFD = pfd;\r
      pEnd = &pPollFD [ nfds ];\r
      while ( pEnd > pPollFD ) {\r
        //\r
        //  Validate the file descriptor\r
        //\r
        if ( !ValidateFD ( pPollFD->fd, VALID_OPEN )) {\r
          errno = EINVAL;\r
          return -1;\r
        }\r
\r
        //\r
        //  Poll the device or file\r
        //\r
        pDescriptor = &gMD->fdarray [ pPollFD->fd ];\r
        pPollFD->revents = pDescriptor->f_ops->fo_poll ( pDescriptor,\r
                                                         pPollFD->events );\r
\r
        //\r
        //  Determine if this file descriptor detected an event\r
        //\r
        if ( 0 != pPollFD->revents ) {\r
          //\r
          //  Select this descriptor\r
          //\r
          SelectedFDs += 1;\r
        }\r
\r
        //\r
        //  Set the next file descriptor\r
        //\r
        pPollFD += 1;\r
      }\r
\r
      //\r
      //  Check for timeout\r
      //\r
      if ( NULL != Timer ) {\r
        Status = gBS->CheckEvent ( Timer );\r
        if ( EFI_SUCCESS == Status ) {\r
          //\r
          //  Timeout\r
          //\r
          break;\r
        }\r
        else if ( EFI_NOT_READY == Status ) {\r
          Status = EFI_SUCCESS;\r
    }\r
    }\r
    } while (( 0 == SelectedFDs )\r
        && ( EFI_SUCCESS == Status ));\r
\r
    //\r
    //  Stop the timer\r
    //\r
    if ( NULL != Timer ) {\r
      gBS->SetTimer ( Timer,\r
                      TimerCancel,\r
                      0 );\r
  }\r
  }\r
  else {\r
    SelectedFDs = -1;\r
    errno = EAGAIN;\r
  }\r
\r
  //\r
  //  Release the timer\r
  //\r
  if ( NULL != Timer ) {\r
    gBS->CloseEvent ( Timer );\r
  }\r
\r
  //\r
  //  Return the number of selected file system descriptors\r
  //\r
  return SelectedFDs;\r
}\r
\r
\r
/** The rename() function changes the name of a file.\r
    The From argument points to the pathname of the file to be renamed. The To\r
    argument points to the new pathname of the file.\r
\r
    If the From argument points to the pathname of a file that is not a\r
    directory, the To argument shall not point to the pathname of a\r
    directory. If the file named by the To argument exists, it shall be\r
    removed and From renamed to To. Write access permission is required for\r
    both the directory containing old and the directory containing To.\r
\r
    If the From argument points to the pathname of a directory, the To\r
    argument shall not point to the pathname of a file that is not a\r
    directory. If the directory named by the To argument exists, it shall be\r
    removed and From renamed to To.\r
\r
    The To pathname shall not contain a path prefix that names From. Write\r
    access permission is required for the directory containing From and the\r
    directory containing To. If the From argument points to the pathname of a\r
    directory, write access permission may be required for the directory named\r
    by From, and, if it exists, the directory named by To.\r
\r
    If the rename() function fails for any reason other than [EIO], any file\r
    named by To shall be unaffected.\r
\r
    @param[in]  From    Path to the file to be renamed.\r
    @param[in]  To      The new name of From.\r
\r
    @retval   0     Successful completion.\r
    @retval   -1    An error has occured and errno has been set to further specify the error.\r
                    Neither the file named by From nor the file named by To are\r
                    changed or created.\r
                      - ENXIO: Path specified is not supported by any loaded driver.\r
                      - ENOMEM: Insufficient memory to calloc a MapName buffer.\r
                      - EINVAL: The path parameter is not valid.\r
**/\r
int\r
rename(\r
  const char *From,\r
  const char *To\r
  )\r
{\r
  wchar_t            *FromPath;\r
  DeviceNode         *FromNode;\r
  char               *GenI;\r
  int                 Instance    = 0;\r
  RETURN_STATUS       Status;\r
  int                 retval      = -1;\r
\r
  Status = ParsePath(From, &FromPath, &FromNode, &Instance, NULL);\r
  if(Status == RETURN_SUCCESS) {\r
    GenI = FromNode->InstanceList;\r
    if(GenI == NULL) {\r
      errno   = EPERM;\r
      retval  = -1;\r
      }\r
      else {\r
      //GenI += (Instance * FromNode->InstanceSize);\r
      retval = ((GenericInstance *)GenI)->Abstraction.fo_rename( From, To);\r
              }\r
    free(FromPath);\r
            }\r
  return retval;\r
}\r
\r
/** Delete a specified directory.\r
\r
    @param[in]  path    Path to the directory to delete.\r
\r
    @retval   -1    The directory couldn't be opened (doesn't exist).\r
    @retval   -1    The directory wasn't empty or an IO error occured.\r
**/\r
int\r
rmdir(\r
  const char *path\r
  )\r
{\r
  struct __filedes   *filp;\r
  int                 fd;\r
  int                 retval = -1;\r
\r
  fd = open(path, O_RDWR, 0);\r
  if(fd >= 0) {\r
    filp = &gMD->fdarray[fd];\r
\r
    retval = filp->f_ops->fo_rmdir(filp);\r
    filp->f_iflags = 0;           // Close this FD\r
    filp->RefCount = 0;           // No one using this FD\r
  }\r
  return retval;\r
}\r
\r
/** The fstat() function obtains information about an open file associated\r
    with the file descriptor fd, and writes it to the area pointed to\r
    by statbuf.\r
\r
    The statbuf argument is a pointer to a stat structure, as defined\r
    in <sys/stat.h>, into which information is placed concerning the file.\r
\r
    The structure members st_mode, st_ino, st_dev, st_uid, st_gid, st_atime,\r
    st_ctime, and st_mtime shall have meaningful values. The value of the\r
    member st_nlink shall be set to the number of links to the file.\r
\r
    The fstat() function shall update any time-related fields before writing\r
    into the stat structure.\r
\r
    The fstat() function is implemented using the ShellGetFileInfo()\r
    function.\r
\r
    The stat structure members which don't have direct analogs to EFI file\r
    information are filled in as follows:\r
      - st_mode     Populated with information from fd\r
      - st_ino      Set to zero.  (inode)\r
      - st_dev      Set to zero.\r
      - st_uid      Set to zero.\r
      - st_gid      Set to zero.\r
      - st_nlink    Set to one.\r
\r
    @param[in]    fd        File descriptor as returned from open().\r
    @param[out]   statbuf   Buffer in which the file status is put.\r
\r
    @retval    0  Successful Completion.\r
    @retval   -1  An error has occurred and errno has been set to\r
                  identify the error.\r
**/\r
int\r
fstat (int fd, struct stat *statbuf)\r
{\r
  int                 retval = -1;\r
  struct __filedes   *filp;\r
\r
  if(ValidateFD( fd, VALID_OPEN)) {\r
    filp = &gMD->fdarray[fd];\r
    retval = filp->f_ops->fo_stat(filp, statbuf, NULL);\r
      }\r
      else {\r
    errno   =  EBADF;\r
      }\r
  return retval;\r
}\r
\r
/** Obtains information about the file pointed to by path.\r
\r
    Opens the file pointed to by path, calls _EFI_FileInfo with the file's handle,\r
    then closes the file.\r
\r
    @param[in]    path      Path to the file to obtain information about.\r
    @param[out]   statbuf   Buffer in which the file status is put.\r
\r
    @retval    0  Successful Completion.\r
    @retval   -1  An error has occurred and errno has been set to\r
                  identify the error.\r
**/\r
int\r
stat   (const char *path, struct stat *statbuf)\r
{\r
  int                 fd;\r
  int                 retval  = -1;\r
  struct __filedes   *filp;\r
\r
  fd = open(path, O_RDONLY, 0);\r
  if(fd >= 0) {\r
    filp = &gMD->fdarray[fd];\r
    retval = filp->f_ops->fo_stat( filp, statbuf, NULL);\r
    close(fd);\r
  }\r
  return retval;\r
}\r
\r
/**  Same as stat since EFI doesn't have symbolic links.\r
\r
    @param[in]    path      Path to the file to obtain information about.\r
    @param[out]   statbuf   Buffer in which the file status is put.\r
\r
    @retval    0  Successful Completion.\r
    @retval   -1  An error has occurred and errno has been set to\r
                  identify the error.\r
**/\r
int\r
lstat (const char *path, struct stat *statbuf)\r
{\r
  return stat(path, statbuf);\r
}\r
\r
/** Control a device.\r
\r
    @param[in]        fd        Descriptor for the file to be acted upon.\r
    @param[in]        request   Specifies the operation to perform.\r
    @param[in,out]    ...       Zero or more parameters as required for request.\r
\r
    @retval   >=0   The operation completed successfully.\r
    @retval   -1    An error occured.  More information is in errno.\r
**/\r
int\r
ioctl(\r
  int             fd,\r
  unsigned long   request,\r
  ...\r
  )\r
{\r
  int                 retval = -1;\r
  struct __filedes   *filp;\r
  va_list             argp;\r
\r
  va_start(argp, request);\r
\r
  if(ValidateFD( fd, VALID_OPEN)) {\r
    filp = &gMD->fdarray[fd];\r
\r
    if(request == FIODLEX) {\r
      /* set Delete-on-Close */\r
      filp->f_iflags |= FIF_DELCLOSE;\r
      retval = 0;\r
    }\r
    else if(request == FIONDLEX) {\r
      /* clear Delete-on-Close */\r
      filp->f_iflags &= ~FIF_DELCLOSE;\r
      retval = 0;\r
    }\r
    else {\r
      /* All other requests. */\r
      retval = filp->f_ops->fo_ioctl(filp, request, argp);\r
    }\r
  }\r
  else {\r
    errno   =  EBADF;\r
  }\r
  va_end(argp);\r
\r
  return retval;\r
}\r
\r
/** Read from a file.\r
\r
    The read() function shall attempt to read nbyte bytes from the file\r
    associated with the open file descriptor, fildes, into the buffer pointed\r
    to by buf.\r
\r
    Before any action described below is taken, and if nbyte is zero, the\r
    read() function may detect and return errors as described below. In the\r
    absence of errors, or if error detection is not performed, the read()\r
    function shall return zero and have no other results.\r
\r
    On files that support seeking (for example, a regular file), the read()\r
    shall start at a position in the file given by the file offset associated\r
    with fildes. The file offset shall be incremented by the number of bytes\r
    actually read.\r
\r
    Files that do not support seeking - for example, terminals - always read\r
    from the current position. The value of a file offset associated with\r
    such a file is undefined.\r
\r
    No data transfer shall occur past the current end-of-file. If the\r
    starting position is at or after the end-of-file, 0 shall be returned.\r
\r
    The read() function reads data previously written to a file. If any\r
    portion of a regular file prior to the end-of-file has not been written,\r
    read() shall return bytes with value 0. For example, lseek() allows the\r
    file offset to be set beyond the end of existing data in the file. If data\r
    is later written at this point, subsequent reads in the gap between the\r
    previous end of data and the newly written data shall return bytes with\r
    value 0 until data is written into the gap.\r
\r
    Upon successful completion, where nbyte is greater than 0, read() shall\r
    mark for update the st_atime field of the file, and shall return the\r
    number of bytes read. This number shall never be greater than nbyte. The\r
    value returned may be less than nbyte if the number of bytes left in the\r
    file is less than nbyte, if the read() request was interrupted by a\r
    signal, or if the file is a pipe or FIFO or special file and has fewer\r
    than nbyte bytes immediately available for reading. For example, a read()\r
    from a file associated with a terminal may return one typed line of data.\r
\r
    If fildes does not refer to a directory, the function reads the requested\r
    number of bytes from the file at the file's current position and returns\r
    them in buf. If the read goes beyond the end of the file, the read\r
    length is truncated to the end of the file. The file's current position is\r
    increased by the number of bytes returned.\r
\r
    If fildes refers to a directory, the function reads the directory entry at\r
    the file's current position and returns the entry in buf. If buf\r
    is not large enough to hold the current directory entry, then\r
    errno is set to EBUFSIZE, EFIerrno is set to EFI_BUFFER_TOO_SMALL, and the\r
    current file position is not updated. The size of the buffer needed to read\r
    the entry will be returned as a negative number. On success, the current\r
    position is updated to the next directory entry. If there are no more\r
    directory entries, the read returns a zero-length buffer.\r
    EFI_FILE_INFO is the structure returned as the directory entry.\r
\r
    @param[in]    fildes  Descriptor of the file to be read.\r
    @param[out]   buf     Pointer to location in which to store the read data.\r
    @param[in]    nbyte   Maximum number of bytes to be read.\r
\r
    @return   Upon successful completion, read() returns a non-negative integer\r
              indicating the number of bytes actually read. Otherwise, the\r
              functions return a negative value and sets errno to indicate the\r
              error.  If errno is EBUFSIZE, the absolute value of the\r
              return value indicates the size of the buffer needed to read\r
              the directory entry.\r
**/\r
ssize_t\r
read   (int fildes, void *buf, size_t nbyte)\r
{\r
  struct __filedes *filp;\r
  cIIO             *IIO;\r
  ssize_t           BufSize;\r
\r
  BufSize = (ssize_t)nbyte;\r
  if(BufSize > 0) {\r
    if(ValidateFD( fildes, VALID_OPEN)) {\r
      filp = &gMD->fdarray[fildes];\r
\r
      IIO = filp->devdata;\r
      if(isatty(fildes) && (IIO != NULL)) {\r
        BufSize = IIO->Read(filp, nbyte, buf);\r
      }\r
      else {\r
        BufSize = filp->f_ops->fo_read(filp, &filp->f_offset, nbyte, buf);\r
      }\r
    }\r
    else {\r
      errno = EBADF;\r
      BufSize = -1;\r
    }\r
  }\r
  return BufSize;\r
}\r
\r
/** Write data to a file.\r
\r
    This function writes the specified number of bytes to the file at the current\r
    file position. The current file position is advanced the actual number of bytes\r
    written. Partial writes only occur when there has been a data error during\r
    the write attempt (such as "volume space full").  The file is automatically\r
    grown to hold the data if required.\r
\r
    Direct writes to opened directories are not supported.\r
\r
    If fildes refers to a terminal device, isatty() returns TRUE, a partial write\r
    will occur if a NULL or EOF character is encountered before n characters have\r
    been written.  Characters inserted due to line-end translations or TAB\r
    expansion will not be counted.  Unconvertable characters are translated into\r
    the UEFI character BLOCKELEMENT_LIGHT_SHADE.\r
\r
    Since the UEFI console device works on wide characters, the buffer is assumed\r
    to contain a byte-oriented multi-byte character stream which is then\r
    translated to wide characters using the mbtowc() functions.  The resulting\r
    wide character stream is what is actually sent to the UEFI console.\r
\r
    Although both text and binary wide-oriented streams are conceptually\r
    sequences of wide characters, the external file associated with a\r
    wide-oriented stream is a sequence of multibyte characters,\r
    generalized as follows:\r
      - Multibyte encodings within files may contain embedded null bytes\r
        (unlike multibyte encodings valid for use internal to the program).\r
      - A file need not begin nor end in the initial shift state.\r
\r
    @param[in]  fd      Descriptor of file to be written to.\r
    @param[in]  buf     Pointer to data to write to the file.\r
    @param[in]  nbyte   Number of bytes to be written to the file.\r
\r
    @retval   >=0   Number of bytes actually written to the file.\r
    @retval   <0    An error occurred.  More data is provided by errno.\r
**/\r
ssize_t\r
write  (int fd, const void *buf, size_t nbyte)\r
{\r
  struct __filedes *filp;\r
  cIIO             *IIO;\r
  ssize_t           BufSize;\r
\r
  BufSize = (ssize_t)nbyte;\r
\r
  if(ValidateFD( fd, VALID_OPEN)) {\r
    filp = &gMD->fdarray[fd];\r
    if ((filp->Oflags & O_ACCMODE) != 0) {\r
      // File is open for writing\r
      IIO = filp->devdata;\r
      if(isatty(fd) && (IIO != NULL)) {\r
        // Output to an Interactive I/O device\r
        // (Terminal device or the slave side of a pseudo-tty)\r
        BufSize = IIO->Write(filp, buf, nbyte);\r
      }\r
      else {\r
        // Output to a regular file, socket, pipe, etc.\r
        BufSize = filp->f_ops->fo_write(filp, &filp->f_offset, nbyte, buf);\r
      }\r
    }\r
    else {\r
      // File is NOT open for writing\r
      errno = EINVAL;\r
      BufSize = -1;\r
    }\r
  }\r
  else {\r
    // fd is not for a valid open file\r
    errno = EBADF;\r
    BufSize = -1;\r
  }\r
  return BufSize;\r
}\r
\r
/** Gets the current working directory.\r
\r
  The getcwd() function shall place an absolute pathname of the current\r
  working directory in the array pointed to by buf, and return buf.The\r
  size argument is the size in bytes of the character array pointed to\r
  by the buf argument.\r
\r
  @param[in,out] buf    The buffer to fill.\r
  @param[in]     size   The number of bytes in buffer.\r
\r
  @retval NULL          The function failed.  The value in errno provides\r
                        further information about the cause of the failure.\r
                        Values for errno are:\r
                          - EINVAL: buf is NULL or size is zero.\r
                          - ENOENT: directory does not exist.\r
                          - ERANGE: buf size is too small to hold CWD\r
\r
  @retval buf           The function completed successfully.\r
**/\r
char\r
*getcwd (char *buf, size_t size)\r
{\r
  CONST CHAR16 *Cwd;\r
\r
  if (size == 0 || buf == NULL) {\r
    errno = EINVAL;\r
    return NULL;\r
    }\r
\r
  Cwd = ShellGetCurrentDir(NULL);\r
  if (Cwd == NULL) {\r
    errno = ENOENT;\r
    return NULL;\r
  }\r
  if (size < ((StrLen (Cwd) + 1) * sizeof (CHAR8))) {\r
    errno = ERANGE;\r
    return (NULL);\r
  }\r
  return (UnicodeStrToAsciiStr(Cwd, buf));\r
}\r
\r
/** Change the current working directory.\r
\r
  The chdir() function shall cause the directory named by the pathname\r
  pointed to by the path argument to become the current working directory;\r
  that is, the starting point for path searches for pathnames not beginning\r
  with '/'.\r
\r
  @param[in] path   The new path to set.\r
\r
  @retval   0   Operation completed successfully.\r
  @retval  -1   Function failed.  The value in errno provides more\r
                information on the cause of failure:\r
                  - EPERM: Operation not supported with this Shell version.\r
                  - ENOMEM: Unable to allocate memory.\r
                  - ENOENT: Target directory does not exist.\r
\r
  @todo Add non-NEW-shell CWD changing.\r
**/\r
int\r
chdir (const char *path)\r
{\r
  CONST CHAR16 *Cwd;\r
  EFI_STATUS   Status;\r
  CHAR16       *UnicodePath;\r
\r
  /* Old Shell does not support Set Current Dir. */\r
  if(gEfiShellProtocol != NULL) {\r
    Cwd = ShellGetCurrentDir(NULL);\r
    if (Cwd != NULL) {\r
      /* We have shell support */\r
      UnicodePath = AllocatePool(((AsciiStrLen (path) + 1) * sizeof (CHAR16)));\r
      if (UnicodePath == NULL) {\r
        errno = ENOMEM;\r
        return -1;\r
      }\r
      AsciiStrToUnicodeStr(path, UnicodePath);\r
      Status = gEfiShellProtocol->SetCurDir(NULL, UnicodePath);\r
      FreePool(UnicodePath);\r
      if (EFI_ERROR(Status)) {\r
        errno = ENOENT;\r
        return -1;\r
      } else {\r
        return 0;\r
      }\r
    }\r
  }\r
  /* Add here for non-shell */\r
  errno = EPERM;\r
  return -1;\r
}\r
\r
/** Get the foreground process group ID associated with a terminal.\r
\r
    Just returns the Image Handle for the requestor since UEFI does not have\r
    a concept of processes or groups.\r
\r
    @param[in]    x   Ignored.\r
\r
    @return   Returns the Image Handle of the application or driver which\r
              called this function.\r
**/\r
pid_t tcgetpgrp (int x)\r
{\r
  return ((pid_t)(UINTN)(gImageHandle));\r
}\r
\r
/** Get the process group ID of the calling process.\r
\r
    Just returns the Image Handle for the requestor since UEFI does not have\r
    a concept of processes or groups.\r
\r
    @return   Returns the Image Handle of the application or driver which\r
              called this function.\r
**/\r
pid_t getpgrp(void)\r
{\r
  return ((pid_t)(UINTN)(gImageHandle));\r
}\r
\r
/* Internal worker function for utimes.\r
    This works around an error produced by GCC when the va_* macros\r
    are used within a function with a fixed number of arguments.\r
*/\r
static\r
int\r
EFIAPI\r
va_Utimes(\r
  const char   *path,\r
  ...\r
  )\r
{\r
  struct __filedes   *filp;\r
  va_list             ap;\r
  int                 fd;\r
  int                 retval  = -1;\r
\r
  va_start(ap, path);\r
  fd = open(path, O_RDWR, 0);\r
  if(fd >= 0) {\r
    filp = &gMD->fdarray[fd];\r
    retval = filp->f_ops->fo_ioctl( filp, FIOSETIME, ap);\r
    close(fd);\r
  }\r
  va_end(ap);\r
  return retval;\r
}\r
\r
/** Set file access and modification times.\r
\r
    @param[in]  path    Path to the file to be modified.\r
    @param[in]  times   Pointer to an array of two timeval structures\r
\r
    @retval   0     File times successfully set.\r
    @retval   -1    An error occured.  Error type in errno.\r
**/\r
int\r
utimes(\r
  const char *path,\r
  const struct timeval *times\r
  )\r
{\r
  return va_Utimes(path, times);\r
}\r