如何使用 Whirlpools 和 Bash 算法重命名带有散列的文件

给定一个目录，我想遍历该目录及其非隐藏子目录，并将一个 whirlpool 散列添加到非隐藏文件的名称中。 如果脚本再次运行，它将用新的散列替换旧的散列。

.   ==>  .. ..   ==>  ..

解决方案

1. Bash 算法

#!/bin/bash
if (($# != 1)) || ! [[ -d "$1" ]]; then
    echo "Usage: $0 /path/to/directory"
    exit 1
fi

is_hash() {
 md5=${1##*.} # strip prefix
 [[ "$md5" == *[^[:xdigit:]]* || ${#md5} -lt 32 ]] && echo "$1" || echo "${1%.*}"
}

while IFS= read -r -d $'\0' file; do
    read hash junk < <(md5sum "$file")
    basename="${file##*/}"
    dirname="${file%/*}"
    pre_ext="${basename%.*}"
    ext="${basename:${#pre_ext}}"

    # File already hashed?
    pre_ext=$(is_hash "$pre_ext")
    ext=$(is_hash "$ext")

    mv "$file" "${dirname}/${pre_ext}.${hash}${ext}" 2> /dev/null

done < <(find "$1" -path "*/.*" -prune -o ( -type f -print0 ))

2. Python 算法

#!/usr/bin/env python
import hashlib, os

def ishash(h, size):
    """Whether `h` looks like hash's hex digest."""
    if len(h) == size: 
        try:
            int(h, 16) # whether h is a hex number
            return True
        except ValueError:
            return False

for root, dirs, files in os.walk("."):
    dirs[:] = [d for d in dirs if not d.startswith(".")] # skip hidden dirs
    for path in (os.path.join(root, f) for f in files if not f.startswith(".")):
        suffix = hash_ = "." + hashlib.md5(open(path).read()).hexdigest()
        hashsize = len(hash_) - 1
        # extract old hash from the name; add/replace the hash if needed
        barepath, ext = os.path.splitext(path) # ext may be empty
        if not ishash(ext[1:], hashsize):
            suffix += ext # add original extension
            barepath, oldhash = os.path.splitext(barepath) 
            if not ishash(oldhash[1:], hashsize):
               suffix = oldhash + suffix # preserve 2nd (not a hash) extension
        else: # ext looks like a hash
            oldhash = ext
        if hash_ != oldhash: # replace old hash by new one
           os.rename(path, barepath+suffix)

3. Perl 算法

#!/usr/bin/perl -w
# whirlpool-rename.pl
# 2009 Peter Cordes <peter@cordes.ca>.  Share and Enjoy!

use Fcntl;      # for O_BINARY
use File::Find;
use Digest::Whirlpool;

# find callback, called once per directory entry
# $_ is the base name of the file, and we are chdired to that directory.
sub whirlpool_rename {
    print "find: $_\n";
    my @components = split /.(?!.|$)/, $_, -1; # -1 to not leave out trailing dots

    if (!$components[0] && $_ ne ".") { # hidden file/directory
        $File::Find::prune = 1;
        return;
    }

    # don't follow symlinks or process non-regular-files
    return if (-l $_ || ! -f _);

    my $digest;
    eval {
        sysopen(my $fh, $_, O_RDONLY | O_BINARY) or die "$!";
        $digest = Digest->new( 'Whirlpool' )->addfile($fh);
    };
    if ($@) {  # exception-catching structure from whirlpoolsum, distributed with Digest::Whirlpool.
        warn "whirlpool: couldn't hash $_: $!\n";
        return;
    }

    # strip old hashes from the name.  not done during split only in the interests of readability
    @components = grep { !/^[[:xdigit:]]{128}$/ }  @components;
    if ($#components == 0) {
        push @components, $digest->hexdigest;
    } else {
        my $ext = pop @components;
        push @components, $digest->hexdigest, $ext;
    }

    my $newname = join('.', @components);
    return if $_ eq $newname;
    print "rename  $_ ->  $newname\n";
    if (-e $newname) {
        warn "whirlpool: clobbering $newname\n";
        # maybe unlink $_ and return if $_ is older than $newname?
        # But you'd better check that $newname has the right contents then...
    }
    # This could be link instead of rename, but then you'd have to handle directories, and you can't make hardlinks across filesystems
    rename $_, $newname or warn "whirlpool: couldn't rename $_ -> $newname:  $!\n";
}


#main
$ARGV[0] = "." if !@ARGV;  # default to current directory
find({wanted => &whirlpool_rename, no_chdir => 0}, @ARGV );

4. Bash 算法（避免遍历隐藏文件）

find -x . -type f -print0 | while IFS="" read -r -d $'\000' file; do
    hash="$(whirlpool "$file")" # replace with your favorite hash function
    [[ "$file" == *."$hash" ]] && continue # skip files that already end in their hash
    dirname="$(dirname "$file")"
    basename="$(basename "$file")"
    base="${basename%.*}"
    [[ "$base" == *."$hash" ]] && continue # skip files that already end in hash + extension
    if [[ "$basename" == "$base" ]]; then
            extension=""
    else
            extension=".${basename##*.}"
    fi
    mv "$file" "$dirname/$base.$hash$extension"
done