/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/* 
 *
 *   Copyright (C) 1997 University of Chicago. 
 *   See COPYRIGHT notice in top-level directory.
 */

#include "ad_nfs.h"

void ADIOI_NFS_Open(ADIO_File fd, int *error_code)
{
    int perm, amode;
    mode_t old_mask;
    static char myname[] = "ADIOI_NFS_OPEN";

    if (fd->perm == ADIO_PERM_NULL) {
	old_mask = umask(022);
	umask(old_mask);
	perm = old_mask ^ 0666;
    }
    else perm = fd->perm;
    
    amode = 0;
    if (fd->access_mode & ADIO_CREATE)
	amode = amode | O_CREAT;
    if (fd->access_mode & ADIO_RDONLY)
	amode = amode | O_RDONLY;
    if (fd->access_mode & ADIO_WRONLY)
	amode = amode | O_WRONLY;
    if (fd->access_mode & ADIO_RDWR)
	amode = amode | O_RDWR;
    if (fd->access_mode & ADIO_EXCL)
	amode = amode | O_EXCL;

#ifdef ADIOI_MPE_LOGGING
    MPE_Log_event( ADIOI_MPE_open_a, 0, NULL );
#endif
    fd->fd_sys = open(fd->filename, amode, perm);
#ifdef ADIOI_MPE_LOGGING
    MPE_Log_event( ADIOI_MPE_open_b, 0, NULL );
#endif
    fd->fd_direct = -1;

    if ((fd->fd_sys != -1) && (fd->access_mode & ADIO_APPEND)) {
#ifdef ADIOI_MPE_LOGGING
        MPE_Log_event( ADIOI_MPE_lseek_a, 0, NULL );
#endif
        fd->fp_ind = fd->fp_sys_posn = lseek(fd->fd_sys, 0, SEEK_END);
#ifdef ADIOI_MPE_LOGGING
        MPE_Log_event( ADIOI_MPE_lseek_b, 0, NULL );
#endif
    }

    if (fd->fd_sys == -1) {
	/* Check for special error codes for those MPI error 
	   classes that relate to particular problems */
	if (errno == ENAMETOOLONG)
	    *error_code = MPIO_Err_create_code(MPI_SUCCESS,
					       MPIR_ERR_RECOVERABLE, myname,
					       __LINE__, MPI_ERR_BAD_FILE,
					       "**filenamelong",
					       "**filenamelong %s %d",
					       fd->filename,
					       strlen(fd->filename));
	else if (errno == ENOENT)
	    *error_code = MPIO_Err_create_code(MPI_SUCCESS,
					       MPIR_ERR_RECOVERABLE, myname,
					       __LINE__, MPI_ERR_NO_SUCH_FILE,
					       "**filenoexist",
					       "**filenoexist %s",
					       fd->filename);
	else if (errno == ENOTDIR || errno == ELOOP)
	    *error_code = MPIO_Err_create_code(MPI_SUCCESS,
					       MPIR_ERR_RECOVERABLE, myname,
					       __LINE__, MPI_ERR_BAD_FILE,
					       "**filenamedir",
					       "**filenamedir %s",
					       fd->filename);
	else if (errno == EACCES) {
	    *error_code = MPIO_Err_create_code(MPI_SUCCESS,
					       MPIR_ERR_RECOVERABLE, myname,
					       __LINE__, MPI_ERR_ACCESS,
					       "**fileaccess",
					       "**fileaccess %s", 
					       fd->filename);
	}
	else if (errno == EROFS) {
	    /* Read only file or file system and write access requested */
	    *error_code = MPIO_Err_create_code(MPI_SUCCESS,
					       MPIR_ERR_RECOVERABLE, myname,
					       __LINE__, MPI_ERR_READ_ONLY,
					       "**ioneedrd", 0);
	}
    else if(errno == EISDIR) {
        *error_code = MPIO_Err_create_code(MPI_SUCCESS,
                           MPIR_ERR_RECOVERABLE, myname,
                           __LINE__, MPI_ERR_BAD_FILE,
                           "**filename", 0);
    }
    else if(errno == EEXIST) {
        *error_code = MPIO_Err_create_code(MPI_SUCCESS,
                           MPIR_ERR_RECOVERABLE, myname,
                           __LINE__, MPI_ERR_FILE_EXISTS,
                           "**fileexist", 0);

    }
	else {
	    *error_code = MPIO_Err_create_code(MPI_SUCCESS,
					       MPIR_ERR_RECOVERABLE, myname,
					       __LINE__, MPI_ERR_IO, "**io",
					       "**io %s", strerror(errno));
	}
    }
    else *error_code = MPI_SUCCESS;
}
