zfec: rearrange files

[tahoe-lafs/zfec.git] / zfec / cmdline_zfec.py

diff --git a/zfec/cmdline_zfec.py b/zfec/cmdline_zfec.py
new file mode 100755 (executable)
index 0000000..2eee2b0
--- /dev/null
+++ b/zfec/cmdline_zfec.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python
+
+# zfec -- a fast C implementation of Reed-Solomon erasure coding with
+# command-line, C, and Python interfaces
+
+import sys
+
+import argparse
+import filefec
+
+from zfec import __version__ as libversion
+__version__ = libversion
+
+DEFAULT_K=3
+DEFAULT_M=8
+
+def main():
+
+    if '-V' in sys.argv or '--version' in sys.argv:
+        print "zfec library version: ", libversion
+        print "zfec command-line tool version: ", __version__
+        sys.exit(0)
+
+    parser = argparse.ArgumentParser(description="Encode a file into a set of share files, a subset of which can later be used to recover the original file.")
+
+    parser.add_argument('inputfile', help='file to encode or "-" for stdin', type=argparse.FileType('rb'), metavar='INF')
+    parser.add_argument('-d', '--output-dir', help='directory in which share file names will be created (default ".")', default='.', metavar='D')
+    parser.add_argument('-p', '--prefix', help='prefix for share file names; If omitted, the name of the input file will be used.', metavar='P')
+    parser.add_argument('-s', '--suffix', help='suffix for share file names (default ".fec")', default='.fec', metavar='S')
+    parser.add_argument('-m', '--totalshares', help='the total number of share files created (default %d)' % DEFAULT_M, default=DEFAULT_M, type=int, metavar='M')
+    parser.add_argument('-k', '--requiredshares', help='the number of share files required to reconstruct (default %d)' % DEFAULT_K, default=DEFAULT_K, type=int, metavar='K')
+    parser.add_argument('-f', '--force', help='overwrite any file which already in place an output file (share file)', action='store_true')
+    parser.add_argument('-v', '--verbose', help='print out messages about progress', action='store_true')
+    parser.add_argument('-q', '--quiet', help='quiet progress indications and warnings about silly choices of K and M', action='store_true')
+    parser.add_argument('-V', '--version', help='print out version number and exit', action='store_true')
+    args = parser.parse_args()
+
+    if args.prefix is None:
+        args.prefix = args.inputfile.name
+        if args.prefix == "<stdin>":
+            args.prefix = ""
+
+    if args.verbose and args.quiet:
+        print "Please choose only one of --verbose and --quiet."
+        sys.exit(1)
+
+    if args.totalshares > 256 or args.totalshares < 1:
+        print "Invalid parameters, totalshares is required to be <= 256 and >= 1\nPlease see the accompanying documentation."
+        sys.exit(1)
+    if args.requiredshares > args.totalshares or args.requiredshares < 1:
+        print "Invalid parameters, requiredshares is required to be <= totalshares and >= 1\nPlease see the accompanying documentation."
+        sys.exit(1)
+
+    if not args.quiet:
+        if args.requiredshares == 1:
+            print "warning: silly parameters: requiredshares == 1, which means that every share will be a complete copy of the file.  You could use \"cp\" for the same effect.  But proceeding to do it anyway..."
+        if args.requiredshares == args.totalshares:
+            print "warning: silly parameters: requiredshares == totalshares, which means that all shares will be required in order to reconstruct the file.  You could use \"split\" for the same effect.  But proceeding to do it anyway..."
+
+    args.inputfile.seek(0, 2)
+    fsize = args.inputfile.tell()
+    args.inputfile.seek(0, 0)
+    return filefec.encode_to_files(args.inputfile, fsize, args.output_dir, args.prefix, args.requiredshares, args.totalshares, args.suffix, args.force, args.verbose)
+
+# zfec -- fast forward error correction library with Python interface
+#
+# Copyright (C) 2007 Allmydata, Inc.
+# Author: Zooko Wilcox-O'Hearn
+#
+# This file is part of zfec.
+#
+# See README.rst for licensing information.