The Tor Browser / file comparison
comparison: build/checksums.py
build/checksums.py
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
equal
deleted
inserted
replaced
| -1:000000000000 | 0:203249bacaf9 |
|---|---|
| 1 #!/usr/bin/python | |
| 2 # This Source Code Form is subject to the terms of the Mozilla Public | |
| 3 # License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 4 # file, You can obtain one at http://mozilla.org/MPL/2.0/. | |
| 5 | |
| 6 from __future__ import with_statement | |
| 7 | |
| 8 from optparse import OptionParser | |
| 9 import logging | |
| 10 import os | |
| 11 try: | |
| 12 import hashlib | |
| 13 except: | |
| 14 hashlib = None | |
| 15 | |
| 16 def digest_file(filename, digest, chunk_size=1024): | |
| 17 '''Produce a checksum for the file specified by 'filename'. 'filename' | |
| 18 is a string path to a file that is opened and read in this function. The | |
| 19 checksum algorithm is specified by 'digest' and is a valid OpenSSL | |
| 20 algorithm. If the digest used is not valid or Python's hashlib doesn't | |
| 21 work, the None object will be returned instead. The size of blocks | |
| 22 that this function will read from the file object it opens based on | |
| 23 'filename' can be specified by 'chunk_size', which defaults to 1K''' | |
| 24 assert not os.path.isdir(filename), 'this function only works with files' | |
| 25 logger = logging.getLogger('checksums.py') | |
| 26 if hashlib is not None: | |
| 27 logger.debug('Creating new %s object' % digest) | |
| 28 h = hashlib.new(digest) | |
| 29 with open(filename, 'rb') as f: | |
| 30 while True: | |
| 31 data = f.read(chunk_size) | |
| 32 if not data: | |
| 33 logger.debug('Finished reading in file') | |
| 34 break | |
| 35 h.update(data) | |
| 36 hash = h.hexdigest() | |
| 37 logger.debug('Hash for %s is %s' % (filename, hash)) | |
| 38 return hash | |
| 39 else: | |
| 40 # In this case we could subprocess.Popen and .communicate with | |
| 41 # sha1sum or md5sum | |
| 42 logger.warn('The python module for hashlib is missing!') | |
| 43 return None | |
| 44 | |
| 45 | |
| 46 def process_files(files, output_filename, digests, strip): | |
| 47 '''This function takes a list of file names, 'files'. It will then | |
| 48 compute the checksum for each of the files by opening the files. | |
| 49 Once each file is read and its checksum is computed, this function | |
| 50 will write the information to the file specified by 'output_filename'. | |
| 51 The path written in the output file will have anything specified by 'strip' | |
| 52 removed from the path. The output file is closed before returning nothing | |
| 53 The algorithm to compute checksums with can be specified by 'digests' | |
| 54 and needs to be a list of valid OpenSSL algorithms. | |
| 55 | |
| 56 The output file is written in the format: | |
| 57 <hash> <algorithm> <filesize> <filepath> | |
| 58 Example: | |
| 59 d1fa09a<snip>e4220 sha1 14250744 firefox-4.0b6pre.en-US.mac64.dmg | |
| 60 ''' | |
| 61 | |
| 62 logger = logging.getLogger('checksums.py') | |
| 63 if os.path.exists(output_filename): | |
| 64 logger.debug('Overwriting existing checksums file "%s"' % | |
| 65 output_filename) | |
| 66 else: | |
| 67 logger.debug('Creating a new checksums file "%s"' % output_filename) | |
| 68 with open(output_filename, 'w+') as output: | |
| 69 for file in files: | |
| 70 if os.path.isdir(file): | |
| 71 logger.warn('%s is a directory, skipping' % file) | |
| 72 else: | |
| 73 for digest in digests: | |
| 74 hash = digest_file(file, digest) | |
| 75 if hash is None: | |
| 76 logger.warn('Unable to generate a hash for %s. ' + | |
| 77 'Skipping.' % file) | |
| 78 continue | |
| 79 if file.startswith(strip): | |
| 80 short_file = file[len(strip):] | |
| 81 short_file = short_file.lstrip('/') | |
| 82 else: | |
| 83 short_file = file | |
| 84 print >>output, '%s %s %s %s' % (hash, digest, | |
| 85 os.path.getsize(file), | |
| 86 short_file) | |
| 87 | |
| 88 def setup_logging(level=logging.DEBUG): | |
| 89 '''This function sets up the logging module using a speficiable logging | |
| 90 module logging level. The default log level is DEBUG. | |
| 91 | |
| 92 The output is in the format: | |
| 93 <level> - <message> | |
| 94 Example: | |
| 95 DEBUG - Finished reading in file | |
| 96 ''' | |
| 97 | |
| 98 logger = logging.getLogger('checksums.py') | |
| 99 logger.setLevel(logging.DEBUG) | |
| 100 handler = logging.StreamHandler() | |
| 101 handler.setLevel(level) | |
| 102 formatter = logging.Formatter("%(levelname)s - %(message)s") | |
| 103 handler.setFormatter(formatter) | |
| 104 logger.addHandler(handler) | |
| 105 | |
| 106 def main(): | |
| 107 '''This is a main function that parses arguments, sets up logging | |
| 108 and generates a checksum file''' | |
| 109 # Parse command line arguments | |
| 110 parser = OptionParser() | |
| 111 parser.add_option('-d', '--digest', help='checksum algorithm to use', | |
| 112 action='append', dest='digests') | |
| 113 parser.add_option('-o', '--output', help='output file to use', | |
| 114 action='store', dest='outfile', default='checksums') | |
| 115 parser.add_option('-v', '--verbose', | |
| 116 help='Be noisy (takes precedence over quiet)', | |
| 117 action='store_true', dest='verbose', default=False) | |
| 118 parser.add_option('-q', '--quiet', help='Be quiet', action='store_true', | |
| 119 dest='quiet', default=False) | |
| 120 parser.add_option('-s', '--strip', | |
| 121 help='strip this path from the filenames', | |
| 122 dest='strip', default=os.getcwd()) | |
| 123 options, args = parser.parse_args() | |
| 124 | |
| 125 #Figure out which logging level to use | |
| 126 if options.verbose: | |
| 127 loglevel = logging.DEBUG | |
| 128 elif options.quiet: | |
| 129 loglevel = logging.ERROR | |
| 130 else: | |
| 131 loglevel = logging.INFO | |
| 132 | |
| 133 #Set up logging | |
| 134 setup_logging(loglevel) | |
| 135 logger = logging.getLogger('checksums.py') | |
| 136 | |
| 137 # Validate the digest type to use | |
| 138 if not options.digests: | |
| 139 options.digests = ['sha1'] | |
| 140 try: | |
| 141 for digest in options.digests: | |
| 142 hashlib.new(digest) | |
| 143 except ValueError, ve: | |
| 144 logger.error('Could not create a "%s" hash object (%s)' % | |
| 145 (digest, ve.args[0])) | |
| 146 exit(1) | |
| 147 | |
| 148 # Validate the files to checksum | |
| 149 files = [] | |
| 150 for i in args: | |
| 151 if os.path.exists(i): | |
| 152 files.append(i) | |
| 153 else: | |
| 154 logger.info('File "%s" was not found on the filesystem' % i) | |
| 155 process_files(files, options.outfile, options.digests, options.strip) | |
| 156 | |
| 157 if __name__ == '__main__': | |
| 158 main() |
