/*
      Code for manipulating files.
*/
#include <petscsys.h>
#if defined(PETSC_HAVE_PWD_H)
#include <pwd.h>
#endif
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#if defined(PETSC_HAVE_UNISTD_H)
#include <unistd.h>
#endif
#if defined(PETSC_HAVE_STDLIB_H)
#include <stdlib.h>
#endif
#if defined(PETSC_HAVE_SYS_UTSNAME_H)
#include <sys/utsname.h>
#endif
#if defined(PETSC_HAVE_SYS_SYSTEMINFO_H)
#include <sys/systeminfo.h>
#endif

#undef __FUNCT__
#define __FUNCT__ "PetscGetHomeDirectory"
/*@C
   PetscGetHomeDirectory - Returns home directory name.

   Not Collective

   Input Parameter:
.  maxlen - maximum lengh allowed

   Output Parameter:
.  dir - contains the home directory. Must be long enough to hold the name.

   Level: developer

   Note:
   If PETSc cannot determine the home directory it makes dir a null string

   On Windows machines the enviornmental variable HOME specifies the home directory.

   Concepts: home directory
@*/
PetscErrorCode  PetscGetHomeDirectory(char dir[],size_t maxlen)
{
  PetscErrorCode ierr;
  char           *d1 = 0;
#if defined(PETSC_HAVE_GETPWUID)
  struct passwd *pw = 0;
#endif

  PetscFunctionBegin;
#if defined(PETSC_HAVE_GETPWUID)
  pw = getpwuid(getuid());
  if (pw) d1 = pw->pw_dir;
#else
  d1 = getenv("HOME");
#endif
  if (d1) {
    ierr = PetscStrncpy(dir,d1,maxlen);CHKERRQ(ierr);
  } else if (maxlen > 0) dir[0] = 0;
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "PetscFixFilename"
/*@C
    PetscFixFilename - Fixes a file name so that it is correct for both Unix and
    Windows by using the correct / or \ to separate directories.

   Not Collective

   Input Parameter:
.  filein - name of file to be fixed

   Output Parameter:
.  fileout - the fixed name. Should long enough to hold the filename.

   Level: advanced

   Notes:
   Call PetscFixFilename() just before calling fopen().
@*/
PetscErrorCode  PetscFixFilename(const char filein[],char fileout[])
{
  PetscErrorCode ierr;
  size_t         i,n;

  PetscFunctionBegin;
  if (!filein || !fileout) PetscFunctionReturn(0);

  ierr = PetscStrlen(filein,&n);CHKERRQ(ierr);
  for (i=0; i<n; i++) {
    if (filein[i] == PETSC_REPLACE_DIR_SEPARATOR) fileout[i] = PETSC_DIR_SEPARATOR;
    else fileout[i] = filein[i];
  }
  fileout[n] = 0;
  PetscFunctionReturn(0);
}