#!/bin/sh

# Copyright (c) 1994 - 2010, Lawrence Livermore National Security, LLC.
# LLNL-CODE-425250.
# All rights reserved.
# 
# This file is part of Silo. For details, see silo.llnl.gov.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 
#    * Redistributions of source code must retain the above copyright
#      notice, this list of conditions and the disclaimer below.
#    * Redistributions in binary form must reproduce the above copyright
#      notice, this list of conditions and the disclaimer (as noted
#      below) in the documentation and/or other materials provided with
#      the distribution.
#    * Neither the name of the LLNS/LLNL nor the names of its
#      contributors may be used to endorse or promote products derived
#      from this software without specific prior written permission.
# 
# THIS SOFTWARE  IS PROVIDED BY  THE COPYRIGHT HOLDERS  AND CONTRIBUTORS
# "AS  IS" AND  ANY EXPRESS  OR IMPLIED  WARRANTIES, INCLUDING,  BUT NOT
# LIMITED TO, THE IMPLIED  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A  PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN  NO  EVENT SHALL  LAWRENCE
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# CONTRIBUTORS BE LIABLE FOR  ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
# EXEMPLARY, OR  CONSEQUENTIAL DAMAGES  (INCLUDING, BUT NOT  LIMITED TO,
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# LIABILITY, WHETHER  IN CONTRACT, STRICT LIABILITY,  OR TORT (INCLUDING
# NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT  OF THE USE  OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# 
# This work was produced at Lawrence Livermore National Laboratory under
# Contract  No.   DE-AC52-07NA27344 with  the  DOE.  Neither the  United
# States Government  nor Lawrence  Livermore National Security,  LLC nor
# any of  their employees,  makes any warranty,  express or  implied, or
# assumes   any   liability   or   responsibility  for   the   accuracy,
# completeness, or usefulness of any information, apparatus, product, or
# process  disclosed, or  represents  that its  use  would not  infringe
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# manufacturer or otherwise does not necessarily constitute or imply its
# endorsement,  recommendation,   or  favoring  by   the  United  States
# Government or Lawrence Livermore National Security, LLC. The views and
# opinions  of authors  expressed  herein do  not  necessarily state  or
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# National  Security, LLC,  and shall  not  be used  for advertising  or
# product endorsement purposes.

#
# Modifications:
#   
#   Mark C. Miller, Wed Jul 14 21:04:10 PDT 2010
#   Completely re-wrote to use od instead of file command as that
#   has proven more reliable.
#

#
# Use octal dump (od) command to examine first few bytes of file.
# If do not find expected bytes of any of the formats we'd like
# to identify here, fall back to using the good ole' file command.
#
unknownFiles=
for f in $*; do
    if test -f $f; then
        headerBytes=$(od -a -N 10 $f)
        if test -n "$(echo $headerBytes | tr -d ' ' | grep '<<PDB:')"; then
            echo "$f: Portable Database (PDB) data"
        elif test -n "$(echo $headerBytes | tr -d ' \\' | grep 'HDFcrnl')"; then
            echo "$f: Hierarchical Data Format version 5 (HDF5) data"
        else
            headerBytes=$(od -t x1 -N 4 $f)
            if test -n "$(echo $headerBytes | grep '0000000 0e 03 13 01')"; then
                echo "$f: Hierarchical Data Format version 4 (HDF4) data"
            else
                file $f
            fi
        fi
    else # not a regular file
        file $f
    fi
done
