hexviewer.py

hexviewer.py

# !/usr/bin/python
"""
Hex Viewer
Licensed under MIT
Copyright (c) 2011 Isaac Muse <[email protected]>
"""
import struct
from os.path import getsize, abspath, normpath
from glob import glob
import sys
import traceback
from time import time

PY3 = sys.version_info >= (3, 0)

DEFAULT_BIT_GROUP = 16
DEFAULT_BYTES_WIDE = 24
VALID_BITS = [8, 16, 32, 64, 128]
VALID_BYTES = [8, 10, 16, 24, 32, 48, 64, 128, 256, 512]
BITS_PER_BYTE = 8

__app__ = "hexviewer"
__version__ = "1.0.1"


class HexViewer(object):
    thread = None

    def __init__(self, silent=False):
        """
        Setup
        """
        self.silent = silent

    def file_init(self, file_name, bit_group, bytes_width):
        """
        Initialize file info and desired formatting of data.
        """

        # File info
        self.file_name = file_name
        self.file_size = getsize(file_name)
        self.read_count = 0

        # Set hex format
        self.set_format(bit_group, bytes_width)

        # Prepare translation tables
        if PY3:
            self.translate_table = str.maketrans("".join([chr(c) for c in range(0, 256)]), "".join(["."] * 32 + [chr(c) for c in range(32, 127)] + ["."] * 129))
        else:
            self.translate_table = ("." * 32) + "".join(chr(c) for c in range(32, 127)) + ("." * 129)
        self.def_struct = struct.Struct("=" + ("B" * self.bytes_wide))
        self.def_template = (("%02x" * self.group_size) + " ") * int(self.bytes_wide / self.group_size)

    def set_format(self, bit_group, byte_width):
        """
        Setup the hex output format.
        """

        self.bits = bit_group if bit_group in VALID_BITS else DEFAULT_BIT_GROUP
        self.bytes = byte_width if byte_width in VALID_BYTES else DEFAULT_BYTES_WIDE

        # Set grouping
        self.group_size = int(self.bits / BITS_PER_BYTE)

        # Set bytes per line
        self.bytes_wide = self.bytes

        # Check if grouping and bytes per line do not align
        # Round to nearest bytes
        offset = self.bytes_wide % self.group_size
        if offset == self.bytes_wide:
            self.bytes_wide = int(self.bits / BITS_PER_BYTE)
        elif offset != 0:
            self.bytes_wide -= offset

    def iterfile(self, maxblocksize=4096):
        """
        Chunk file
        """

        with open(self.file_name, "rb") as f:
            # Ensure read block is a multiple of groupsize
            bytes_wide = self.bytes_wide
            blocksize = maxblocksize - (maxblocksize % bytes_wide)

            start = 0
            byte_array = f.read(blocksize)
            while byte_array:
                outbytes = byte_array[start:start + bytes_wide]
                while outbytes:
                    yield outbytes
                    start += bytes_wide
                    outbytes = byte_array[start:start + bytes_wide]
                start = 0
                byte_array = f.read(blocksize)

    def to_hex(self):
        """
        Parse file and convert to hex.
        """

        self.abort = False
        with open(self.file_name + ".hex", "w") as f:
            line = 0
            read_count = 0

            if not self.silent:
                last_time = time()

            for byte_array in self.iterfile():
                l_buffer = []

                read_count += self.bytes_wide
                self.read_count = read_count if read_count < self.file_size else self.file_size

                # Add line number
                l_buffer.append("%08x:  " % (line * self.bytes_wide))

                if len(byte_array) == self.bytes_wide:
                    # Complete line
                    # Convert to decimal value
                    values = self.def_struct.unpack(byte_array)

                    # Add hex value
                    l_buffer.append(self.def_template % values)
                else:
                    # Incomplete line
                    # Convert to decimal value
                    values = struct.unpack("=" + ("B" * len(byte_array)), byte_array)

                    # Add hex value
                    remain_group = int(len(byte_array) / self.group_size)
                    remain_extra = len(byte_array) % self.group_size
                    l_buffer.append(((("%02x" * self.group_size) + " ") * (remain_group) + ("%02x" * remain_extra)) % values)

                    # Calculate extra space
                    delta = self.bytes_wide - len(byte_array)
                    group_space = int(delta / self.group_size)
                    extra_space = (1 if delta % self.group_size else 0)

                    l_buffer.append(" " * (group_space + extra_space + delta * 2))

                # Append printable chars
                if PY3:
                    l_buffer.append(" :" + "".join([chr(self.translate_table[b]) for b in byte_array]))
                else:
                    l_buffer.append(" :" + byte_array.translate(self.translate_table))

                # Write to file
                f.write("".join(l_buffer) + '\n')

                line += 1

                # Log status
                if not self.silent:
                    if time() - last_time > 0.5:
                        self.status()
                        last_time = time()

            # Update status for final time
            if not self.silent:
                self.status()

    def status(self):
        """
        Display conversion status.
        """

        ratio = float(self.read_count) / float(self.file_size)
        percent = int(ratio * 10)
        leftover = 10 - percent
        message = "    [" + "-" * percent + ">" + "-" * leftover + ("] %3d%%" % int(ratio * 100)) + " converted to hex\r"
        sys.stdout.write(message)
        sys.stdout.flush()

    def convert(self, file_name, bit_group=DEFAULT_BIT_GROUP, bytes_width=DEFAULT_BYTES_WIDE):
        """
        Convert file to hex with the specified format.
        """

        self.file_init(file_name, bit_group, bytes_width)

        if not self.silent:
            print("Converting %s..." % self.file_name)

        # Read bin
        self.to_hex()

        if not self.silent:
            print('\n')


def get_files(file_patterns):
    """
    Find and return files matching the given patterns.
    """

    files = []
    all_files = []
    if len(file_patterns):
        for pattern in file_patterns:
            files += glob(pattern)
    for f in files:
        all_files.append(abspath(normpath(f)))
    return all_files


def main():
    """
    Main
    """
    import argparse

    status = 0

    # Parse arguments
    parser = argparse.ArgumentParser(prog=__app__, description='Convert file to hex.')
    parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
    parser.add_argument('--debug', '-d', action='store_true', default=False, help=argparse.SUPPRESS)
    parser.add_argument('--bits', '-b', nargs=1, default=False, help="Bits per group")
    parser.add_argument('--bytes', '-B', nargs=1, default=False, help="Bytes per line")
    parser.add_argument('--silent', '-s', action='store_true', default=False, help="No output.")
    parser.add_argument('files', nargs='+', default=[], help='file(s) or file pattern(s) to convert')
    args = parser.parse_args()

    hexviewer = HexViewer(silent=args.silent)
    files = get_files(args.files)
    total = len(files)
    converted = 0
    for f in files:
        try:
            hexviewer.convert(f, int(args.bits), int(args.bytes))
            converted += 1
        except:
            print(traceback.format_exc())
            status = 1
            if not args.silent:
                print("ERROR: Could not convert %s!\n" % f)
    if not args.silent:
        print("%d/%d files converted!" % (converted, total))

    return status


if __name__ == "__main__":
    sys.exit(main())