pattern attr1 attr2 ...
That is, a pattern followed by an attributes list,
-separated by whitespaces. When the pattern matches the
-path in question, the attributes listed on the line are given to
-the path.
+separated by whitespaces. Leading and trailing whitespaces are
+ignored. Lines that begin with '#' are ignored. Patterns
+that begin with a double quote are quoted in C style.
+When the pattern matches the path in question, the attributes
+listed on the line are given to the path.
Each attribute can be in one of these states for a given path:
Attributes for all users on a system should be placed in the
`$(prefix)/etc/gitattributes` file.
-Sometimes you would need to override an setting of an attribute
+Sometimes you would need to override a setting of an attribute
for a path to `Unspecified` state. This can be done by listing
the name of the attribute prefixed with an exclamation point `!`.
This attribute sets a specific line-ending style to be used in the
working directory. It enables end-of-line conversion without any
-content checks, effectively setting the `text` attribute.
+content checks, effectively setting the `text` attribute. Note that
+setting this attribute on paths which are in the index with CRLF line
+endings may make the paths to be considered dirty. Adding the path to
+the index again will normalize the line endings in the index.
Set to string value "crlf"::
-------------------------------------------------
$ echo "* text=auto" >.gitattributes
-$ rm .git/index # Remove the index to force Git to
-$ git reset # re-scan the working directory
+$ git add --renormalize .
$ git status # Show files that will be normalized
-$ git add -u
-$ git add .gitattributes
$ git commit -m "Introduce end-of-line normalization"
-------------------------------------------------
into a usable content by setting the filter.<driver>.required configuration
variable to `true`.
+Note: Whenever the clean filter is changed, the repo should be renormalized:
+$ git add --renormalize .
+
For example, in .gitattributes, you would assign the `filter`
attribute for paths.
packet: git< capability=smudge
packet: git< 0000
------------------------
-Supported filter capabilities in version 2 are "clean" and
-"smudge".
+Supported filter capabilities in version 2 are "clean", "smudge",
+and "delay".
Afterwards Git sends a list of "key=value" pairs terminated with
a flush packet. The list will contain at least the filter command
with the next file that needs to be processed. Depending on the
`filter.<driver>.required` flag Git will interpret that as error.
-After the filter has processed a blob it is expected to wait for
-the next "key=value" list containing a command. Git will close
+After the filter has processed a command it is expected to wait for
+a "key=value" list containing the next command. Git will close
the command pipe on exit. The filter is expected to detect EOF
and exit gracefully on its own. Git will wait until the filter
process has stopped.
+Delay
+^^^^^
+
+If the filter supports the "delay" capability, then Git can send the
+flag "can-delay" after the filter command and pathname. This flag
+denotes that the filter can delay filtering the current blob (e.g. to
+compensate network latencies) by responding with no content but with
+the status "delayed" and a flush packet.
+------------------------
+packet: git> command=smudge
+packet: git> pathname=path/testfile.dat
+packet: git> can-delay=1
+packet: git> 0000
+packet: git> CONTENT
+packet: git> 0000
+packet: git< status=delayed
+packet: git< 0000
+------------------------
+
+If the filter supports the "delay" capability then it must support the
+"list_available_blobs" command. If Git sends this command, then the
+filter is expected to return a list of pathnames representing blobs
+that have been delayed earlier and are now available.
+The list must be terminated with a flush packet followed
+by a "success" status that is also terminated with a flush packet. If
+no blobs for the delayed paths are available, yet, then the filter is
+expected to block the response until at least one blob becomes
+available. The filter can tell Git that it has no more delayed blobs
+by sending an empty list. As soon as the filter responds with an empty
+list, Git stops asking. All blobs that Git has not received at this
+point are considered missing and will result in an error.
+
+------------------------
+packet: git> command=list_available_blobs
+packet: git> 0000
+packet: git< pathname=path/testfile.dat
+packet: git< pathname=path/otherfile.dat
+packet: git< 0000
+packet: git< status=success
+packet: git< 0000
+------------------------
+
+After Git received the pathnames, it will request the corresponding
+blobs again. These requests contain a pathname and an empty content
+section. The filter is expected to respond with the smudged content
+in the usual way as explained above.
+------------------------
+packet: git> command=smudge
+packet: git> pathname=path/testfile.dat
+packet: git> 0000
+packet: git> 0000 # empty content!
+packet: git< status=success
+packet: git< 0000
+packet: git< SMUDGED_CONTENT
+packet: git< 0000
+packet: git< 0000 # empty list, keep "status=success" unchanged!
+------------------------
+
+Example
+^^^^^^^
+
A long running filter demo implementation can be found in
`contrib/long-running-filter/example.pl` located in the Git
core repository. If you develop your own long running filter