Standard Libraries for EDK II.

[mirror_edk2.git] / StdLib / LibC / StdLib / Environs.c

/** @file\r
  Implementation of the <stdlib.h> functions responsible for communication with\r
  the environment:\r
    - abort(void)\r
    - atexit(void(*handler)(void))\r
    - exit(int status)\r
    - _Exit(int status)\r
\r
  Copyright (c) 2010, 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.php.\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/UefiBootServicesTableLib.h>\r
#include  <Library/BaseLib.h>\r
#include  <Library/MemoryAllocationLib.h>\r
#include  <Library/ShellLib.h>\r
\r
#include  <LibConfig.h>\r
\r
#include  <errno.h>\r
#include  <signal.h>\r
#include  <stdlib.h>\r
#include  <MainData.h>\r
\r
/* #################  Public Functions  ################################### */\r
\r
/** The abort function causes abnormal program termination to occur, unless\r
    the signal SIGABRT is being caught and the signal handler does not return.\r
\r
    Open streams with unwritten buffered data are not flushed, open\r
    streams are not closed, and temporary files are not removed by abort.\r
\r
**/\r
void\r
abort(void)\r
{\r
  if (!gMD->aborting) {\r
    gMD->aborting = TRUE;\r
\r
    if (gMD->cleanup != NULL) {\r
      gMD->cleanup();\r
    }\r
  }\r
  raise(SIGABRT);\r
  _Exit(EXIT_FAILURE);  // In case raise returns.\r
}\r
\r
/** The atexit function registers the function pointed to by func, to be\r
    called without arguments at normal program termination.\r
\r
    The implementation shall support the registration of\r
    at least 32 functions.\r
\r
    @return   The atexit function returns zero if the registration succeeds,\r
              nonzero if it fails.\r
**/\r
int\r
atexit(void (*handler)(void))\r
{\r
  int   retval = 1;\r
\r
  if((handler != NULL) && (gMD->num_atexit < ATEXIT_MAX)) {\r
    gMD->atexit_handler[gMD->num_atexit++] = handler;\r
    retval = 0;\r
  }\r
  return retval;\r
}\r
\r
/** The exit function causes normal program termination to occur. If more than\r
    one call to the exit function is executed by a program,\r
    the behavior is undefined.\r
\r
    First, all functions registered by the atexit function are called, in the\r
    reverse order of their registration. If, during the call to any such function, a\r
    call to the longjmp function is made that would terminate the call to the\r
    registered function, the behavior is undefined.\r
\r
    Next, all open streams with unwritten buffered data are flushed, all open\r
    streams are closed, and all files created by the tmpfile function\r
    are removed.\r
\r
    The status returned to the host environment is determined in the same way\r
    as for the _Exit function.\r
**/\r
void\r
exit(int status)\r
{\r
  int i = gMD->num_atexit;\r
\r
  // Call all registered atexit functions in reverse order\r
  if( i > 0) {\r
    do {\r
      (gMD->atexit_handler[--i])();\r
    } while( i > 0);\r
  }\r
\r
  if (gMD->cleanup != NULL) {\r
    gMD->cleanup();\r
  }\r
  _Exit(status);\r
}\r
\r
typedef\r
EFI_STATUS\r
(EFIAPI *ExitFuncPtr)(\r
  IN  EFI_HANDLE                   ImageHandle,\r
  IN  EFI_STATUS                   ExitStatus,\r
  IN  UINTN                        ExitDataSize,\r
  IN  CHAR16                       *ExitData     OPTIONAL\r
) __noreturn;\r
\r
/** The _Exit function causes normal program termination to occur and control\r
    to be returned to the host environment.\r
\r
    No functions registered by the atexit function or signal handlers\r
    registered by the signal function are called.  Open streams with unwritten\r
    buffered data are not flushed, open streams are not closed, and temporary\r
    files are not removed by abort.\r
\r
    Finally, control is returned to the host environment. If the value of\r
    status is zero, or EXIT_SUCCESS, status is returned unchanged. If the value\r
    of status is EXIT_FAILURE, RETURN_ABORTED is returned.\r
    Otherwise, status is returned unchanged.\r
**/\r
void\r
_Exit(int status)\r
{\r
  RETURN_STATUS ExitVal = (RETURN_STATUS)status;\r
  ExitFuncPtr   ExitFunc;\r
\r
  if( ExitVal == EXIT_FAILURE) {\r
    ExitVal = RETURN_ABORTED;\r
  }\r
\r
  ExitFunc = (ExitFuncPtr)gBS->Exit;\r
\r
  //gBS->Exit(gImageHandle, ExitVal, 0, NULL);   /* abort() */\r
  ExitFunc(gImageHandle, ExitVal, 0, NULL);   /* abort() */\r
}\r
\r
/** If string is a null pointer, the system function determines whether the\r
    host environment has a command processor. If string is not a null pointer,\r
    the system function passes the string pointed to by string to that command\r
    processor to be executed in a manner which the implementation shall\r
    document; this might then cause the program calling system to behave in a\r
    non-conforming manner or to terminate.\r
\r
    @retval   EXIT_FAILURE    EFIerrno will contain the EFI status code\r
                              indicating the cause of failure.\r
\r
    @retval   EXIT_SUCCESS    EFIerrno will contain the EFI status returned\r
                              by the executed command string.\r
    @retval   0               If string is NULL, 0 means a command processor\r
                              is not available.\r
    @retval   1               If string is NULL, 1 means a command processor\r
                              is available.\r
**/\r
int\r
system(const char *string)\r
{\r
  EFI_STATUS  CmdStat;\r
  EFI_STATUS  OpStat;\r
  EFI_HANDLE  MyHandle = gImageHandle;\r
\r
  if( string == NULL) {\r
    return 1;\r
  }\r
  (void)AsciiStrToUnicodeStr( string, gMD->UString);\r
  OpStat = ShellExecute( &MyHandle, gMD->UString, FALSE, NULL, &CmdStat);\r
  if(OpStat == RETURN_SUCCESS) {\r
    EFIerrno = CmdStat;\r
    return EXIT_SUCCESS;\r
  }\r
  EFIerrno = OpStat;\r
  return EXIT_FAILURE;\r
}\r
\r
/** The getenv function searches an environment list, provided by the host\r
    environment, for a string that matches the string pointed to by name.  The\r
    set of environment names and the method for altering the environment list\r
    are determined by the underlying UEFI Shell implementation.\r
\r
    @return   The getenv function returns a pointer to a string associated with\r
              the matched list member.  The string pointed to shall not be\r
              modified by the program, but may be overwritten by a subsequent\r
              call to the getenv function.  If the specified name cannot be\r
              found, a null pointer is returned.\r
**/\r
char   *getenv(const char *name)\r
{\r
  const CHAR16  *EfiEnv;\r
  char          *retval = NULL;\r
\r
  (void)AsciiStrToUnicodeStr( name, gMD->UString);\r
  EfiEnv = ShellGetEnvironmentVariable(gMD->UString);\r
  if(EfiEnv != NULL) {\r
    retval = UnicodeStrToAsciiStr( EfiEnv, gMD->ASgetenv);\r
  }\r
\r
  return retval;\r
}\r