author | Pulkit Goyal <7895pulkit@gmail.com> |
Fri, 05 May 2017 01:41:54 +0530 | |
changeset 32155 | 055cca8e167b |
parent 31280 | 1b699a208cee |
permissions | -rw-r--r-- |
31280
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parents:
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The censor system allows retroactively removing content from |
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parents:
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files. Actually censoring a node requires using the censor extension, |
1b699a208cee
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parents:
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but the functionality for handling censored nodes is partially in core. |
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Censored nodes in a filelog have the flag ``REVIDX_ISCENSORED`` set, |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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and the contents of the censored node are replaced with a censor |
1b699a208cee
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parents:
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tombstone. For historical reasons, the tombstone is packed in the |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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filelog metadata field ``censored``. This allows censored nodes to be |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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(mostly) safely transmitted through old formats like changegroup |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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versions 1 and 2. When using changegroup formats older than 3, the |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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receiver is required to re-add the ``REVIDX_ISCENSORED`` flag when |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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storing the revision. This depends on the ``censored`` metadata key |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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never being used for anything other than censoring revisions, which is |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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true as of January 2017. Note that the revlog flag is the |
1b699a208cee
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parents:
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authoritative marker of a censored node: the tombstone should only be |
1b699a208cee
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parents:
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consulted when looking for a reason a node was censored or when revlog |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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flags are unavailable as mentioned above. |
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The tombstone data is a free-form string. It's expected that users of |
1b699a208cee
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parents:
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censor will want to record the reason for censoring a node in the |
1b699a208cee
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parents:
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tombstone. Censored nodes must be able to fit in the size of the |
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content being censored. |