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1 files changed, 186 insertions, 0 deletions

diff --git a/Demo/pdist/cvslib.py b/Demo/pdist/cvslib.py
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+"""Utilities to read and write CVS admin files (esp. CVS/Entries)"""
+
+import string
+import os
+import time
+
+
+class Entry:
+
+	"""Class representing one (parsed) line from CVS/Entries"""
+	
+	def __init__(self, line):
+		words = string.splitfields(line, '/')
+		self.file = words[1]
+		self.rev = words[2]
+		dates = words[3] # ctime, mtime
+		if dates[:7] == 'Initial':
+			self.ctime = None
+			self.mtime = None
+			self.new = 1
+		else:
+			self.ctime = unctime(dates[:24])
+			self.mtime = unctime(dates[25:])
+			self.new = 0
+		self.extra = words[4]
+		self.sum = None
+	
+	def unparse(self):
+		if self.new:
+			dates = "Initial %s" % self.file
+		else:
+			dates = gmctime(self.ctime) + ' ' + gmctime(self.mtime)
+		return "/%s/%s/%s/%s/\n" % (
+			self.file,
+			self.rev,
+			dates,
+			self.extra)
+	
+	def setsum(self, sum):
+		self.sum = sum
+	
+	def getsum(self):
+		return self.sum
+	
+	def sethexsum(self, hexsum):
+		self.setsum(unhexify(hexsum))
+	
+	def gethexsum(self):
+		if self.sum:
+			return hexify(self.sum)
+		else:
+			return None
+
+
+class CVS:
+
+	"""Class representing the contents of CVS/Entries (and CVS/Sums)"""
+	
+	def __init__(self):
+		self.readentries()
+	
+	def readentries(self):
+		self.entries = {}
+		f = self.cvsopen("Entries")
+		while 1:
+			line = f.readline()
+			if not line: break
+			e = Entry(line)
+			self.entries[e.file] = e
+		f.close()
+	
+	def readsums(self):
+		try:
+			f = self.cvsopen("Sums")
+		except IOError:
+			return
+		while 1:
+			line = f.readline()
+			if not line: break
+			words = string.split(line)
+			[file, rev, hexsum] = words
+			e = self.entries[file]
+			if e.rev == rev:
+				e.sethexsum(hexsum)
+		f.close()
+	
+	def writeentries(self):
+		f = self.cvsopen("Entries", 'w')
+		for file in self.keys():
+			f.write(self.entries[file].unparse())
+		f.close()
+	
+	def writesums(self):
+		if self.cvsexists("Sums"):
+			f = self.cvsopen("Sums", 'w')
+		else:
+			f = None
+		for file in self.keys():
+			e = self.entries[file]
+			hexsum = e.gethexsum()
+			if hexsum:
+				if not f:
+					f = self.cvsopen("Sums", 'w')
+				f.write("%s %s %s\n" % (file, e.rev, hexsum))
+		if f:
+			f.close()
+	
+	def keys(self):
+		keys = self.entries.keys()
+		keys.sort()
+		return keys
+
+	def cvsexists(self, file):
+		file = os.path.join("CVS", file)
+		return os.path.exists(file)
+	
+	def cvsopen(self, file, mode = 'r'):
+		file = os.path.join("CVS", file)
+		if 'r' not in mode:
+			self.backup(file)
+		return open(file, mode)
+	
+	def backup(self, file):
+		if os.path.isfile(file):
+			bfile = file + '~'
+			os.rename(file, bfile)
+
+
+hexify_format = '%02x' * 16
+def hexify(sum):
+	"Return a hex representation of a 16-byte string (e.g. an MD5 digest)"
+	return hexify_format % tuple(map(ord, sum))
+
+def unhexify(hexsum):
+	"Return the original from a hexified string"
+	sum = ''
+	for i in range(0, len(hexsum), 2):
+		sum = sum + chr(string.atoi(hexsum[i:i+2], 16))
+	return sum
+
+
+unctime_monthmap = {}
+def unctime(date):
+	if not unctime_monthmap:
+		months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
+			  'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
+		i = 0
+		for m in months:
+			i = i+1
+			unctime_monthmap[m] = i
+	words = string.split(date) # Day Mon DD HH:MM:SS YEAR
+	year = string.atoi(words[4])
+	month = unctime_monthmap[words[1]]
+	day = string.atoi(words[2])
+	[hh, mm, ss] = map(string.atoi, string.splitfields(words[3], ':'))
+	ss = ss - time.timezone
+	return time.mktime((year, month, day, hh, mm, ss, 0, 0, 0))
+
+def gmctime(t):
+	return time.asctime(time.gmtime(t))
+
+def test_unctime():
+	now = int(time.time())
+	t = time.gmtime(now)
+	at = time.asctime(t)
+	print 'GMT', now, at
+	print 'timezone', time.timezone
+	print 'local', time.ctime(now)
+	u = unctime(at)
+	print 'unctime()', u
+	gu = time.gmtime(u)
+	print '->', gu
+	print time.asctime(gu)
+
+def test():
+	x = CVS()
+	keys = x.entries.keys()
+	keys.sort()
+	for file in keys:
+		e = x.entries[file]
+		print file, e.rev, gmctime(e.ctime), gmctime(e.mtime), e.extra,
+		print e.gethexsum()
+
+
+if __name__ == "__main__":
+	test()