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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Remove all remaining print statements Convert most prints to ui.warn or ui.write Pass a write function into transactions manifest hash: d1b0af7a344fc087a5acfe3ae87b782c20d043e0 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (GNU/Linux) iD8DBQFCx1Q3ywK+sNU5EO8RAqSTAJwM5t/m+JOlf2ZXOjuItCSdFiubcwCdFm3G HoicikSYpTgfCj2pIRfyLjo= =Loqo -----END PGP SIGNATURE-----
79 lines
2.2 KiB
Python
79 lines
2.2 KiB
Python
# transaction.py - simple journalling scheme for mercurial
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#
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# This transaction scheme is intended to gracefully handle program
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# errors and interruptions. More serious failures like system crashes
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# can be recovered with an fsck-like tool. As the whole repository is
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# effectively log-structured, this should amount to simply truncating
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# anything that isn't referenced in the changelog.
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#
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# Copyright 2005 Matt Mackall <mpm@selenic.com>
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#
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# This software may be used and distributed according to the terms
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# of the GNU General Public License, incorporated herein by reference.
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import os
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import util
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class transaction:
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def __init__(self, report, opener, journal, after = None):
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self.journal = None
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# abort here if the journal already exists
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if os.path.exists(journal):
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raise "journal already exists - run hg recover"
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self.report = report
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self.opener = opener
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self.after = after
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self.entries = []
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self.map = {}
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self.journal = journal
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self.file = open(self.journal, "w")
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def __del__(self):
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if self.journal:
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if self.entries: self.abort()
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self.file.close()
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try: os.unlink(self.journal)
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except: pass
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def add(self, file, offset):
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if file in self.map: return
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self.entries.append((file, offset))
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self.map[file] = 1
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# add enough data to the journal to do the truncate
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self.file.write("%s\0%d\n" % (file, offset))
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self.file.flush()
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def close(self):
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self.file.close()
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self.entries = []
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if self.after:
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util.rename(self.journal, self.after)
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else:
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os.unlink(self.journal)
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self.journal = None
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def abort(self):
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if not self.entries: return
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self.report("transaction abort!\n")
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for f, o in self.entries:
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try:
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self.opener(f, "a").truncate(o)
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except:
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self.report("failed to truncate %s\n" % f)
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self.entries = []
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self.report("rollback completed\n")
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def rollback(opener, file):
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for l in open(file).readlines():
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f, o = l.split('\0')
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opener(f, "a").truncate(int(o))
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os.unlink(file)
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