The smudge/clean filter API expect an external process is spawned
to filter the contents for each path that has a filter defined. A
new type of "process" filter API has been added to allow the first
request to run the filter for a path to spawn a single process, and
all filtering need is served by this single process for multiple
paths, reducing the process creation overhead.
* ls/filter-process:
contrib/long-running-filter: add long running filter example
convert: add filter.<driver>.process option
convert: prepare filter.<driver>.process option
convert: make apply_filter() adhere to standard Git error handling
pkt-line: add functions to read/write flush terminated packet streams
pkt-line: add packet_write_gently()
pkt-line: add packet_flush_gently()
pkt-line: add packet_write_fmt_gently()
pkt-line: extract set_packet_header()
pkt-line: rename packet_write() to packet_write_fmt()
run-command: add clean_on_exit_handler
run-command: move check_pipe() from write_or_die to run_command
convert: modernize tests
convert: quote filter names in error messages
Mark error messages about CRLF for translation.
Update test to reflect changes.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git's clean/smudge mechanism invokes an external filter process for
every single blob that is affected by a filter. If Git filters a lot of
blobs then the startup time of the external filter processes can become
a significant part of the overall Git execution time.
In a preliminary performance test this developer used a clean/smudge
filter written in golang to filter 12,000 files. This process took 364s
with the existing filter mechanism and 5s with the new mechanism. See
details here: https://github.com/github/git-lfs/pull/1382
This patch adds the `filter.<driver>.process` string option which, if
used, keeps the external filter process running and processes all blobs
with the packet format (pkt-line) based protocol over standard input and
standard output. The full protocol is explained in detail in
`Documentation/gitattributes.txt`.
A few key decisions:
* The long running filter process is referred to as filter protocol
version 2 because the existing single shot filter invocation is
considered version 1.
* Git sends a welcome message and expects a response right after the
external filter process has started. This ensures that Git will not
hang if a version 1 filter is incorrectly used with the
filter.<driver>.process option for version 2 filters. In addition,
Git can detect this kind of error and warn the user.
* The status of a filter operation (e.g. "success" or "error) is set
before the actual response and (if necessary!) re-set after the
response. The advantage of this two step status response is that if
the filter detects an error early, then the filter can communicate
this and Git does not even need to create structures to read the
response.
* All status responses are pkt-line lists terminated with a flush
packet. This allows us to send other status fields with the same
protocol in the future.
Helped-by: Martin-Louis Bright <mlbright@gmail.com>
Reviewed-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor the existing 'single shot filter mechanism' and prepare the
new 'long running filter mechanism'.
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply_filter() returns a boolean that tells the caller if it
"did convert or did not convert". The variable `ret` was used throughout
the function to track errors whereas `1` denoted success and `0`
failure. This is unusual for the Git source where `0` denotes success.
Rename the variable and flip its value to make the function easier
readable for Git developers.
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git filter driver commands with spaces (e.g. `filter.sh foo`) are hard
to read in error messages. Quote them to improve the readability.
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a non-reversible CRLF conversion is done in "git add",
a warning is printed on stderr (or Git dies, depending on checksafe)
The function commit_chk_wrnNNO() in t0027 was written to test this,
but did the wrong thing: Instead of looking at the warning
from "git add", it looked at the warning from "git commit".
This is racy because "git commit" may not have to do CRLF conversion
at all if it can use the sha1 value from the index (which depends on
whether "add" and "commit" run in a single second).
Correct t0027 and replace the commit for each and every file with a commit
of all files in one go.
The function commit_chk_wrnNNO() should be renamed in a separate commit.
Now that t0027 does the right thing, it detects a bug in covert.c:
This sequence should generate the warning `LF will be replaced by CRLF`,
but does not:
$ git init
$ git config core.autocrlf false
$ printf "Line\r\n" >file
$ git add file
$ git commit -m "commit with CRLF"
$ git config core.autocrlf true
$ printf "Line\n" >file
$ git add file
"git add" calls crlf_to_git() in convert.c, which calls check_safe_crlf().
When has_cr_in_index(path) is true, crlf_to_git() returns too early and
check_safe_crlf() is not called at all.
Factor out the code which determines if "git checkout" converts LF->CRLF
into will_convert_lf_to_crlf().
Update the logic around check_safe_crlf() and "simulate" the possible
LF->CRLF conversion at "git checkout" with help of will_convert_lf_to_crlf().
Thanks to Jeff King <peff@peff.net> for analyzing t0027.
Reported-By: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before this change,
$ echo "* text=auto" >.gitattributes
$ echo "* eol=crlf" >>.gitattributes
would have the same effect as
$ echo "* text" >.gitattributes
$ git config core.eol crlf
Since the 'eol' attribute had higher priority than 'text=auto', this may
corrupt binary files and is not what most users expect to happen.
Make the 'eol' attribute to obey 'text=auto' and now
$ echo "* text=auto" >.gitattributes
$ echo "* eol=crlf" >>.gitattributes
behaves the same as
$ echo "* text=auto" >.gitattributes
$ git config core.eol crlf
In other words,
$ echo "* text=auto eol=crlf" >.gitattributes
has the same effect as
$ git config core.autocrlf true
and
$ echo "* text=auto eol=lf" >.gitattributes
has the same effect as
$ git config core.autocrlf input
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the ident attributes is set, get_stream_filter() did not obey
core.autocrlf=true, and the file was checked out with LF.
Change the rule when a streaming filter can be used:
- if an external filter is specified, don't use a stream filter.
- if the worktree eol is CRLF and "auto" is active, don't use a stream filter.
- Otherwise the stream filter can be used.
Add test cases in t0027.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
df747b81 (convert.c: refactor crlf_action, 2016-02-10) introduced a
bug to "git ls-files --eol".
The "text" attribute was shown as "text eol=lf" or "text eol=crlf",
depending on core.autocrlf or core.eol.
Correct this and add test cases in t0027.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Simplify the statistics:
lonecr counts the CR which is not followed by a LF,
lonelf counts the LF which is not preceded by a CR,
crlf counts CRLF combinations.
This simplifies the evaluation of the statistics.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor the determination and usage of crlf_action.
Today, when no "crlf" attribute are set on a file, crlf_action is set to
CRLF_GUESS. Use CRLF_UNDEFINED instead, and search for "text" or "eol" as
before.
After searching for line ending attributes, save the value in
struct conv_attrs.crlf_action attr_action,
so that get_convert_attr_ascii() is able report the attributes.
Replace the old CRLF_GUESS usage:
CRLF_GUESS && core.autocrlf=true -> CRLF_AUTO_CRLF
CRLF_GUESS && core.autocrlf=false -> CRLF_BINARY
CRLF_GUESS && core.autocrlf=input -> CRLF_AUTO_INPUT
Save the action in conv_attrs.crlf_action (as before) and change
all callers.
Make more clear, what is what, by defining:
- CRLF_UNDEFINED : No attributes set. Temparally used, until core.autocrlf
and core.eol is evaluated and one of CRLF_BINARY,
CRLF_AUTO_INPUT or CRLF_AUTO_CRLF is selected
- CRLF_BINARY : No processing of line endings.
- CRLF_TEXT : attribute "text" is set, line endings are processed.
- CRLF_TEXT_INPUT: attribute "input" or "eol=lf" is set. This implies text.
- CRLF_TEXT_CRLF : attribute "eol=crlf" is set. This implies text.
- CRLF_AUTO : attribute "auto" is set.
- CRLF_AUTO_INPUT: core.autocrlf=input (no attributes)
- CRLF_AUTO_CRLF : core.autocrlf=true (no attributes)
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clean/smudge filters defined in a configuration file of lower
precedence can now be overridden to be a pass-through no-op by
setting the variable to an empty string.
* ls/clean-smudge-override-in-config:
convert: treat an empty string for clean/smudge filters as "cat"
Add a helper function to find out, which line endings text files
should get at checkout, depending on core.autocrlf and core.eol
configuration variables.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Integrate the code of input_crlf_action() into convert_attrs(),
so that ca.crlf_action is always valid after calling convert_attrs().
Keep a copy of crlf_action in attr_action, this is needed for
get_convert_attr_ascii().
Remove eol_attr from struct conv_attrs, as it is now used temporally.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some functions get a parameter path, but don't use it.
Remove the unused parameter.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Once a lower-priority configuration file defines a clean or smudge
filter, there is no convenient way to override it to produce as-is
output. Even though the configuration mechanism implements "the
last one wins" semantics, you cannot set them to an empty string and
expect them to work, as apply_filter() would try to run the empty
string as an external command and fail. The conversion is not done,
but the function would still report a failure to convert.
Even though resetting the variable to "cat" (i.e. pass the data back
as-is and report success) is an obvious and a viable way to solve
this, it is wasteful to spawn an external process just as a
workaround.
Instead, teach apply_filter() to treat an empty string as a no-op
filter that always returns successfully its input as-is without
conversion.
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When working in a cross-platform environment, a user may want to
check if text files are stored normalized in the repository and
if .gitattributes are set appropriately.
Make it possible to let Git show the line endings in the index and
in the working tree and the effective text/eol attributes.
The end of line ("eolinfo") are shown like this:
"-text" binary (or with bare CR) file
"none" text file without any EOL
"lf" text file with LF
"crlf" text file with CRLF
"mixed" text file with mixed line endings.
The effective text/eol attribute is one of these:
"", "-text", "text", "text=auto", "text eol=lf", "text eol=crlf"
git ls-files --eol gives an output like this:
i/none w/none attr/text=auto t/t5100/empty
i/-text w/-text attr/-text t/test-binary-2.png
i/lf w/lf attr/text eol=lf t/t5100/rfc2047-info-0007
i/lf w/crlf attr/text eol=crlf doit.bat
i/mixed w/mixed attr/ locale/XX.po
to show what eol convention is used in the data in the index ('i'),
and in the working tree ('w'), and what attribute is in effect,
for each path that is shown.
Add test cases in t0027.
Helped-By: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We sometimes sprintf into fixed-size buffers when we know
that the buffer is large enough to fit the input (either
because it's a constant, or because it's numeric input that
is bounded in size). Likewise with strcpy of constant
strings.
However, these sites make it hard to audit sprintf and
strcpy calls for buffer overflows, as a reader has to
cross-reference the size of the array with the input. Let's
use xsnprintf instead, which communicates to a reader that
we don't expect this to overflow (and catches the mistake in
case we do).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We are explicitly ignoring SIGPIPE, as we fully expect that the
filter program may not read our output fully. Ignore EPIPE that
may come from writing to it as well.
A new test was stolen from Jeff's suggestion.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When running a required clean filter, we do not have to mmap the
original before feeding the filter. Instead, stream the file
contents directly to the filter and process its output.
* sp/stream-clean-filter:
sha1_file: don't convert off_t to size_t too early to avoid potential die()
convert: stream from fd to required clean filter to reduce used address space
copy_fd(): do not close the input file descriptor
mmap_limit: introduce GIT_MMAP_LIMIT to allow testing expected mmap size
memory_limit: use git_env_ulong() to parse GIT_ALLOC_LIMIT
config.c: add git_env_ulong() to parse environment variable
convert: drop arguments other than 'path' from would_convert_to_git()
The data is streamed to the filter process anyway. Better avoid mapping
the file if possible. This is especially useful if a clean filter
reduces the size, for example if it computes a sha1 for binary data,
like git media. The file size that the previous implementation could
handle was limited by the available address space; large files for
example could not be handled with (32-bit) msysgit. The new
implementation can filter files of any size as long as the filter output
is small enough.
The new code path is only taken if the filter is required. The filter
consumes data directly from the fd. If it fails, the original data is
not immediately available. The condition can easily be handled as
a fatal error, which is expected for a required filter anyway.
If the filter was not required, the condition would need to be handled
in a different way, like seeking to 0 and reading the data. But this
would require more restructuring of the code and is probably not worth
it. The obvious approach of falling back to reading all data would not
help achieving the main purpose of this patch, which is to handle large
files with limited address space. If reading all data is an option, we
can simply take the old code path right away and mmap the entire file.
The environment variable GIT_MMAP_LIMIT, which has been introduced in
a previous commit is used to test that the expected code path is taken.
A related test that exercises required filters is modified to verify
that the data actually has been modified on its way from the file system
to the object store.
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Most struct child_process variables are cleared using memset first after
declaration. Provide a macro, CHILD_PROCESS_INIT, that can be used to
initialize them statically instead. That's shorter, doesn't require a
function call and is slightly more readable (especially given that we
already have STRBUF_INIT, ARGV_ARRAY_INIT etc.).
Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's a common idiom to match a prefix and then skip past it
with a magic number, like:
if (starts_with(foo, "bar"))
foo += 3;
This is easy to get wrong, since you have to count the
prefix string yourself, and there's no compiler check if the
string changes. We can use skip_prefix to avoid the magic
numbers here.
Note that some of these conversions could be much shorter.
For example:
if (starts_with(arg, "--foo=")) {
bar = arg + 6;
continue;
}
could become:
if (skip_prefix(arg, "--foo=", &bar))
continue;
However, I have left it as:
if (skip_prefix(arg, "--foo=", &v)) {
bar = v;
continue;
}
to visually match nearby cases which need to actually
process the string. Like:
if (skip_prefix(arg, "--foo=", &v)) {
bar = atoi(v);
continue;
}
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.
The change can be recreated by mechanically applying this:
$ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
grep -v strbuf\\.c |
xargs perl -pi -e '
s|!prefixcmp\(|starts_with\(|g;
s|prefixcmp\(|!starts_with\(|g;
s|!suffixcmp\(|ends_with\(|g;
s|suffixcmp\(|!ends_with\(|g;
'
on the result of preparatory changes in this series.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reduce duplicated code between convert.c and attr.c.
* lf/read-blob-data-from-index:
convert.c: remove duplicate code
read_blob_data_from_index(): optionally return the size of blob data
attr.c: extract read_index_data() as read_blob_data_from_index()
The has_cr_in_index() function is an almost 1:1 copy of
read_blob_data_from_index() with some additions. Use the
latter instead of using copy-pasted code.
Signed-off-by: Lukas Fleischer <git@cryptocrack.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These callers can drop some inline pointer arithmetic and
magic offset constants, making them more readable and less
error-prone (those constants had to match the lengths of
strings, but there is no automatic verification of that
fact).
The "ep" pointer (presumably for "end pointer"), which
points to the final key segment of the config variable, is
given the more standard name "key" to describe its function
rather than its derivation.
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jk/maint-avoid-streaming-filtered-contents:
do not stream large files to pack when filters are in use
teach dry-run convert_to_git not to require a src buffer
teach convert_to_git a "dry run" mode
When we call convert_to_git in dry-run mode, it may still
want to look at the source buffer, because some CRLF
conversion modes depend on analyzing the source to determine
whether it is in fact convertible CRLF text.
However, the main motivation for convert_to_git's dry-run
mode is that we would decide which method to use to acquire
the blob's data (streaming versus in-core). Requiring this
source analysis creates a chicken-and-egg problem. We are
better off simply guessing that anything we can't analyze
will end up needing conversion.
This patch lets a caller specify a NULL src buffer when
using dry-run mode (and only dry-run mode). A non-zero
return value goes from "we would convert" to "we might
convert"; a zero return value remains "we would definitely
not convert".
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some callers may want to know whether convert_to_git will
actually do anything before performing the conversion
itself (e.g., to decide whether to stream or handle blobs
in-core). This patch lets callers specify the dry run mode
by passing a NULL destination buffer. The return value,
instead of indicating whether conversion happened, will
indicate whether conversion would occur.
For readability, we also include a wrapper function which
makes it more obvious we are not actually performing the
conversion.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a filter is not defined or if it fails, git should behave as if the
filter is a no-op passthru.
However, if the filter exits before reading all the content, depending on
the timing, git could be killed with SIGPIPE when it tries to write to the
pipe connected to the filter.
Ignore SIGPIPE while processing the filter to give us a chance to check
the return value from a failed write, in order to detect and act on this
mode of failure in a more controlled way.
Signed-off-by: Jehan Bing <jehan@orb.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By default, a missing filter driver or a failure from the filter driver is
not an error, but merely makes the filter operation a no-op pass through.
This is useful to massage the content into a shape that is more convenient
for the platform, filesystem, and the user to use, and the content filter
mechanism is not used to turn something unusable into usable.
However, we could also use of the content filtering mechanism and store
the content that cannot be directly used in the repository (e.g. a UUID
that refers to the true content stored outside git, or an encrypted
content) and turn it into a usable form upon checkout (e.g. download the
external content, or decrypt the encrypted content). For such a use case,
the content cannot be used when filter driver fails, and we need a way to
tell Git to abort the whole operation for such a failing or missing filter
driver.
Add a new "filter.<driver>.required" configuration variable to mark the
second use case. When it is set, git will abort the operation when the
filter driver does not exist or exits with a non-zero status code.
Signed-off-by: Jehan Bing <jehan@orb.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The non-streaming version of the filter counts CRLF and LF in the whole
buffer, and returns without doing anything when they match (i.e. what is
recorded in the object store already uses CRLF). This was done to help
people who added files from the DOS world before realizing they want to go
cross platform and adding .gitattributes to tell Git that they only want
CRLF in their working tree.
The streaming version of the filter does not want to read the whole thing
before starting to work, as that defeats the whole point of streaming. So
we instead check what byte follows CR whenever we see one, and add CR
before LF only when the LF does not immediately follow CR already to keep
CRLF as is.
Reported-and-tested-by: Ralf Thielow
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This can only happen when the input size is multiple of the
buffer size of the cascade filter (16k) and ends with an LF,
but in such a case, the code forgot to tell the caller that
it added the "\n" it could not add during the last round.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There may not be enough space to store CRLF in the output. If we don't
fill the buffer, then the filter will keep getting called with the same
short buffer and will loop forever.
Instead, always store the CR and record whether there's a missing LF
if so we store it in the output buffer the next time the function gets
called.
Reported-by: Henrik Grubbström <grubba@roxen.com>
Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git_path_check_eol() function converts a string value to the
corresponding 'enum eol' value. However, the function is currently
declared to return an 'enum crlf_action', which causes sparse to
complain thus:
SP convert.c
convert.c:736:50: warning: mixing different enum types
convert.c:736:50: int enum crlf_action versus
convert.c:736:50: int enum eol
In order to suppress the warning, we simply correct the return type
in the function declaration.
Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
convert_to_git sets src=dst->buf if any of the preceding conversions
actually did any work. Thus in ident_to_git we have to use memmove
instead of memcpy as far as src->dst copying is concerned.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Suggested by: Junio Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add support for "ident" filter on the output codepath. This does not work
with lf-to-crlf filter together (yet).
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some filters may need to buffer the input and look-ahead inside it
to decide what to output, and they may consume more than zero bytes
of input and still not produce any output. After feeding all the
input, pass NULL as input as keep calling stream_filter() to let
such filters know there is no more input coming, and it is time for
them to produce the remaining output based on the buffered input.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This introduces an API to plug custom filters to an input stream.
The caller gets get_stream_filter("path") to obtain an appropriate
filter for the path, and then uses it when opening an input stream
via open_istream(). After that, the caller can read from the stream
with read_istream(), and close it with close_istream(), just like an
unfiltered stream.
This only adds a "null" filter that is a pass-thru filter, but later
changes can add LF-to-CRLF and other filters, and the callers of the
streaming API do not have to change.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the output to a path does not have to be converted, we can read from
the object database from the streaming API and write to the file in the
working tree, without having to hold everything in the memory.
The ident, auto- and safe- crlf conversions inherently require you to read
the whole thing before deciding what to do, so while it is technically
possible to support them by using a buffer of an unbound size or rewinding
and reading the stream twice, it is less practical than the traditional
"read the whole thing in core and convert" approach.
Adding streaming filters for the other conversions on top of this should
be doable by tweaking the can_bypass_conversion() function (it should be
renamed to can_filter_stream() when it happens). Then the streaming API
can be extended to wrap the git_istream streaming_write_entry() opens on
the underlying object in another git_istream that reads from it, filters
what is read, and let the streaming_write_entry() read the filtered
result. But that is outside the scope of this series.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The current internal API requires the callers of setup_convert_check() to
supply the git_attr_check structures (hence they need to know how many to
allocate), but they grab the same set of attributes for given path.
Define a new convert_attrs() API that fills a higher level information that
the callers (convert_to_git and convert_to_working_tree) really want, and
move the common code to interact with the attributes system to it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The places that need to pass an array of "struct git_attr_check" needed to
be careful to pass a large enough array and know what index each element
lied. Make it safer and easier to code these.
Besides, the hard-coded sequence of initializing various attributes was
too ugly after we gained more than a few attributes.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Back when the conversion was only about the end-of-line convention, it
might have made sense to call what we do upon seeing CR/LF simply an
"action", but these days the conversion routines do a lot more than just
tweaking the line ending. Raname "action" to "crlf_action".
The function that decides what end of line conversion to use on the output
codepath was called "determine_output_conversion", as if there is no other
kind of output conversion. Rename it to "output_eol"; it is a function
that returns what EOL convention is to be used.
A function that decides what "crlf_action" needs to be used on the input
codepath, given what conversion attribute is set to the path and global
end-of-line convention, was called "determine_action". Rename it to
"input_crlf_action".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Yes, it is clear that "eol" wants to mean some sort of end-of-line thing,
but as the name of a global variable, it is way too short to describe what
kind of end-of-line thing it wants to represent. Besides, there are many
codepaths that want to use their own local "char *eol" variable to point
at the end of the current line they are processing.
This global variable holds what we read from core.eol configuration
variable. Name it as such.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since v1.7.2-rc0~23^2~2 (Add per-repository eol normalization,
2010-05-19), building with gcc -std=gnu89 -pedantic produces warnings
like the following:
convert.c:21:11: warning: comma at end of enumerator list [-pedantic]
gcc is right to complain --- these commas are not permitted in C89.
In the spirit of v1.7.2-rc0~32^2~16 (2010-05-14), remove them.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Filtering to support keyword expansion may need the name of
the file being filtered. In particular, to support p4 keywords
like
$File: //depot/product/dir/script.sh $
the smudge filter needs to know the name of the file it is
smudging.
Allow "%f" in the custom filter command line specified in the
configuration. This will be substituted by the filename
inside a single-quote pair to be passed to the shell.
Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Disable CRLF expansion when convert_to_working_tree() is called from
normalize_buffer(). This improves performance when merging branches
with conflicting line endings when core.eol=crlf or core.autocrlf=true
by making the normalization act as if core.eol=lf.
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, merging across changes in line ending normalization is
painful since files containing CRLF will conflict with normalized files,
even if the only difference between the two versions is the line
endings. Additionally, any "real" merge conflicts that exist are
obscured because every line in the file has a conflict.
Assume you start out with a repo that has a lot of text files with CRLF
checked in (A):
o---C
/ \
A---B---D
B: Add "* text=auto" to .gitattributes and normalize all files to
LF-only
C: Modify some of the text files
D: Try to merge C
You will get a ridiculous number of LF/CRLF conflicts when trying to
merge C into D, since the repository contents for C are "wrong" wrt the
new .gitattributes file.
Fix ll-merge so that the "base", "theirs" and "ours" stages are passed
through convert_to_worktree() and convert_to_git() before a three-way
merge. This ensures that all three stages are normalized in the same
way, removing from consideration differences that are only due to
normalization.
This feature is optional for now since it changes a low-level mechanism
and is not necessary for the majority of users. The "merge.renormalize"
config variable enables it.
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* gv/portable:
test-lib: use DIFF definition from GIT-BUILD-OPTIONS
build: propagate $DIFF to scripts
Makefile: Tru64 portability fix
Makefile: HP-UX 10.20 portability fixes
Makefile: HPUX11 portability fixes
Makefile: SunOS 5.6 portability fix
inline declaration does not work on AIX
Allow disabling "inline"
Some platforms lack socklen_t type
Make NO_{INET_NTOP,INET_PTON} configured independently
Makefile: some platforms do not have hstrerror anywhere
git-compat-util.h: some platforms with mmap() lack MAP_FAILED definition
test_cmp: do not use "diff -u" on platforms that lack one
fixup: do not unconditionally disable "diff -u"
tests: use "test_cmp", not "diff", when verifying the result
Do not use "diff" found on PATH while building and installing
enums: omit trailing comma for portability
Makefile: -lpthread may still be necessary when libc has only pthread stubs
Rewrite dynamic structure initializations to runtime assignment
Makefile: pass CPPFLAGS through to fllow customization
Conflicts:
Makefile
wt-status.h
Introduce a new configuration variable, "core.eol", that allows the user
to set which line endings to use for end-of-line-normalized files in the
working directory. It defaults to "native", which means CRLF on Windows
and LF everywhere else.
Note that "core.autocrlf" overrides core.eol. This means that
[core]
autocrlf = true
puts CRLFs in the working directory even if core.eol is set to "lf".
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unfortunately, there are still plenty of production systems with
vendor compilers that choke unless all compound declarations can be
determined statically at compile time, for example hpux10.20 (I can
provide a comprehensive list of our supported platforms that exhibit
this problem if necessary).
This patch simply breaks apart any compound declarations with dynamic
initialisation expressions, and moves the initialisation until after
the last declaration in the same block, in all the places necessary to
have the offending compilers accept the code.
Signed-off-by: Gary V. Vaughan <gary@thewrittenword.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As discussed on the list, "crlf" is not an optimal name. Linus
suggested "text", which is much better.
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the semantics of the "crlf" attribute so that it enables
end-of-line normalization when it is set, regardless of "core.autocrlf".
Add a new setting for "crlf": "auto", which enables end-of-line
conversion but does not override the automatic text file detection.
Add a new attribute "eol" with possible values "crlf" and "lf". When
set, this attribute enables normalization and forces git to use CRLF or
LF line endings in the working directory, respectively.
The line ending style to be used for normalized text files in the
working directory is set using "core.autocrlf". When it is set to
"true", CRLFs are used in the working directory; when set to "input" or
"false", LFs are used.
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, autocrlf would only work well for normalized
repositories. Any text files that contained CRLF in the repository
would cause problems, and would be modified when handled with
core.autocrlf set.
Change autocrlf to not do any conversions to files that in the
repository already contain a CR. git with autocrlf set will never
create such a file, or change a LF only file to contain CRs, so the
(new) assumption is that if a file contains a CR, it is intentional,
and autocrlf should not change that.
The following sequence should now always be a NOP even with autocrlf
set (assuming a clean working directory):
git checkout <something>
touch *
git add -A . (will add nothing)
git commit (nothing to commit)
Previously this would break for any text file containing a CR.
Some of you may have been folowing Eyvind's excellent thread about
trying to make end-of-line translation in git a bit smoother.
I decided to attack the problem from a different angle: Is it possible
to make autocrlf behave non-destructively for all the previous problem cases?
Stealing the problem from Eyvind's initial mail (paraphrased and
summarized a bit):
1. Setting autocrlf globally is a pain since autocrlf does not work well
with CRLF in the repo
2. Setting it in individual repos is hard since you do it "too late"
(the clone will get it wrong)
3. If someone checks in a file with CRLF later, you get into problems again
4. If a repository once has contained CRLF, you can't tell autocrlf
at which commit everything is sane again
5. autocrlf does needless work if you know that all your users want
the same EOL style.
I belive that this patch makes autocrlf a safe (and good) default
setting for Windows, and this solves problems 1-4 (it solves 2 by being
set by default, which is early enough for clone).
I implemented it by looking for CR charactes in the index, and
aborting any conversion attempt if this is found.
Signed-off-by: Finn Arne Gangstad <finag@pvv.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If there are foreign $Id$ keywords in the repository, they are most
likely there for a reason. Let's keep them on checkout (which is also
what the documentation indicates). Foreign $Id$ keywords are now
recognized by there being multiple space separated fields in $Id:xxxxx$.
Signed-off-by: Henrik Grubbström <grubba@grubba.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to contract $Id:xxxxx$ strings could eat an arbitrary amount
of source text if the terminating $ was lost. It now refuses to
contract $Id:xxxxx$ strings spanning multiple lines.
Signed-off-by: Henrik Grubbström <grubba@grubba.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* sp/maint-push-sideband:
receive-pack: Send hook output over side band #2
receive-pack: Wrap status reports inside side-band-64k
receive-pack: Refactor how capabilities are shown to the client
send-pack: demultiplex a sideband stream with status data
run-command: support custom fd-set in async
run-command: Allow stderr to be a caller supplied pipe
Update git fsck --full short description to mention packs
Conflicts:
run-command.c
This patch adds the possibility to supply a set of non-0 file
descriptors for async process communication instead of the
default-created pipe.
Additionally, we now support bi-directional communiction with the
async procedure, by giving the async function both read and write
file descriptors.
To retain compatiblity and similar "API feel" with start_command,
we require start_async callers to set .out = -1 to get a readable
file descriptor. If either of .in or .out is 0, we supply no file
descriptor to the async process.
[sp: Note: Erik started this patch, and a huge bulk of it is
his work. All bugs were introduced later by Shawn.]
Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/conflict-marker-size:
rerere: honor conflict-marker-size attribute
rerere: prepare for customizable conflict marker length
conflict-marker-size: new attribute
rerere: use ll_merge() instead of using xdl_merge()
merge-tree: use ll_merge() not xdl_merge()
xdl_merge(): allow passing down marker_size in xmparam_t
xdl_merge(): introduce xmparam_t for merge specific parameters
git_attr(): fix function signature
Conflicts:
builtin-merge-file.c
ll-merge.c
xdiff/xdiff.h
xdiff/xmerge.c
The function took (name, namelen) as its arguments, but all the public
callers wanted to pass a full string.
Demote the counted-string interface to an internal API status, and allow
public callers to just pass the string to the function.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that we have the use_shell feature, these callsites can
all be converted with small changes.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As a general guideline, functions in git's code return zero to indicate
success and negative values to indicate failure. The run_command family of
functions followed this guideline. But there are actually two different
kinds of failure:
- failures of system calls;
- non-zero exit code of the program that was run.
Usually, a non-zero exit code of the program is a failure and means a
failure to the caller. Except that sometimes it does not. For example, the
exit code of merge programs (e.g. external merge drivers) conveys
information about how the merge failed, and not all exit calls are
actually failures.
Furthermore, the return value of run_command is sometimes used as exit
code by the caller.
This change arranges that the exit code of the program is returned as a
positive value, which can now be regarded as the "result" of the function.
System call failures continue to be reported as negative values.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many call sites use strbuf_init(&foo, 0) to initialize local
strbuf variable "foo" which has not been accessed since its
declaration. These can be replaced with a static initialization
using the STRBUF_INIT macro which is just as readable, saves a
function call, and takes up fewer lines.
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
git_config() only had a function parameter, but no callback data
parameter. This assumes that all callback functions only modify
global variables.
With this patch, every callback gets a void * parameter, and it is hoped
that this will help the libification effort.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
CRLF conversion bears a slight chance of corrupting data.
autocrlf=true will convert CRLF to LF during commit and LF to
CRLF during checkout. A file that contains a mixture of LF and
CRLF before the commit cannot be recreated by git. For text
files this is the right thing to do: it corrects line endings
such that we have only LF line endings in the repository.
But for binary files that are accidentally classified as text the
conversion can corrupt data.
If you recognize such corruption early you can easily fix it by
setting the conversion type explicitly in .gitattributes. Right
after committing you still have the original file in your work
tree and this file is not yet corrupted. You can explicitly tell
git that this file is binary and git will handle the file
appropriately.
Unfortunately, the desired effect of cleaning up text files with
mixed line endings and the undesired effect of corrupting binary
files cannot be distinguished. In both cases CRLFs are removed
in an irreversible way. For text files this is the right thing
to do because CRLFs are line endings, while for binary files
converting CRLFs corrupts data.
This patch adds a mechanism that can either warn the user about
an irreversible conversion or can even refuse to convert. The
mechanism is controlled by the variable core.safecrlf, with the
following values:
- false: disable safecrlf mechanism
- warn: warn about irreversible conversions
- true: refuse irreversible conversions
The default is to warn. Users are only affected by this default
if core.autocrlf is set. But the current default of git is to
leave core.autocrlf unset, so users will not see warnings unless
they deliberately chose to activate the autocrlf mechanism.
The safecrlf mechanism's details depend on the git command. The
general principles when safecrlf is active (not false) are:
- we warn/error out if files in the work tree can modified in an
irreversible way without giving the user a chance to backup the
original file.
- for read-only operations that do not modify files in the work tree
we do not not print annoying warnings.
There are exceptions. Even though...
- "git add" itself does not touch the files in the work tree, the
next checkout would, so the safety triggers;
- "git apply" to update a text file with a patch does touch the files
in the work tree, but the operation is about text files and CRLF
conversion is about fixing the line ending inconsistencies, so the
safety does not trigger;
- "git diff" itself does not touch the files in the work tree, it is
often run to inspect the changes you intend to next "git add". To
catch potential problems early, safety triggers.
The concept of a safety check was originally proposed in a similar
way by Linus Torvalds. Thanks to Dimitry Potapov for insisting
on getting the naked LF/autocrlf=true case right.
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
There are two heuristics in Git to detect whether a file is binary
or text. One in xdiff-interface.c (which is taken from GNU diff)
relies on existence of the NUL byte at the beginning. However,
convert.c used a different heuristic, which relied on the percent
of non-printable symbols (less than 1% for text files).
Due to differences in detection whether a file is binary or not,
it was possible that a file that diff treats as binary could be
treated as text by CRLF conversion. This is very confusing for a
user who sees that 'git diff' shows the file as binary expects it
to be added as binary.
This patch makes is_binary to consider any file that contains at
least one NUL character as binary, to ensure that the heuristics
used for CRLF conversion is tighter than what is used by diff.
Signed-off-by: Dmitry Potapov <dpotapov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When apply_filter() runs the external (clean or smudge) filter program, it
needs to pass the writable end of a pipe as its stdout. For this purpose,
it used to dup2(2) the file descriptor explicitly to stdout. Now we use
the facilities of start_command() to do it for us.
Furthermore, the path argument of a subordinate function, filter_buffer(),
was not used, so here we replace it to pass the fd instead.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The previous code already used finish_command() to wait for the process
to terminate, but did not use start_command() to run it.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* crlf_to_git and ident_to_git:
Don't grow the buffer if there is enough space in the first place.
As a side effect, when the editing is done "in place", we don't grow, so
the buffer pointer doesn't changes, and `src' isn't invalidated anymore.
Thanks to Bernt Hansen for the bug report.
* apply_filter:
Fix memory leak due to fake in-place editing that didn't collected the
old buffer when the filter succeeds. Also a cosmetic fix.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
For that purpose, the ->buf is always initialized with a char * buf living
in the strbuf module. It is made a char * so that we can sloppily accept
things that perform: sb->buf[0] = '\0', and because you can't pass "" as an
initializer for ->buf without making gcc unhappy for very good reasons.
strbuf_init/_detach/_grow have been fixed to trust ->alloc and not ->buf
anymore.
as a consequence strbuf_detach is _mandatory_ to detach a buffer, copying
->buf isn't an option anymore, if ->buf is going to escape from the scope,
and eventually be free'd.
API changes:
* strbuf_setlen now always works, so just make strbuf_reset a convenience
macro.
* strbuf_detatch takes a size_t* optional argument (meaning it can be
NULL) to copy the buffer's len, as it was needed for this refactor to
make the code more readable, and working like the callers.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Now, those functions take an "out" strbuf argument, where they store their
result if any. In that case, it also returns 1, else it returns 0.
* those functions support "in place" editing, in the sense that it's OK to
call them this way:
convert_to_git(path, sb->buf, sb->len, sb);
When doable, conversions are done in place for real, else the strbuf
content is just replaced with the new one, transparentely for the caller.
If you want to create a new filter working this way, being the accumulation
of filter1, filter2, ... filtern, then your meta_filter would be:
int meta_filter(..., const char *src, size_t len, struct strbuf *sb)
{
int ret = 0;
ret |= filter1(...., src, len, sb);
if (ret) {
src = sb->buf;
len = sb->len;
}
ret |= filter2(...., src, len, sb);
if (ret) {
src = sb->buf;
len = sb->len;
}
....
return ret | filtern(..., src, len, sb);
}
That's why subfilters the convert_to_* functions called were also rewritten
to work this way.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
convert_sha1_file() became unused by the previous patch -- remove it.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the repository contained an expanded ident keyword (i.e. $Id:XXXX$),
then the wrong bytes were discarded, and the Id keyword was not
expanded. The fault was in convert.c:ident_to_worktree().
Previously, when a "$Id:" was found in the repository version,
ident_to_worktree() would search for the next "$" after this, and
discarded everything it found until then. That was done with the loop:
do {
ch = *cp++;
if (ch == '$')
break;
rem--;
} while (rem);
The above loop left cp pointing one character _after_ the final "$"
(because of ch = *cp++). This was different from the non-expanded case,
were cp is left pointing at the "$", and was different from the comment
which stated "discard up to but not including the closing $". This
patch fixes that by making the loop:
do {
ch = *cp;
if (ch == '$')
break;
cp++;
rem--;
} while (rem);
That is, cp is tested _then_ incremented.
This loop exits if it finds a "$" or if it runs out of bytes in the
source. After this loop, if there was no closing "$" the expansion is
skipped, and the outer loop is allowed to continue leaving this
non-keyword as it was. However, when the "$" is found, size is
corrected, before running the expansion:
size -= (cp - src);
This is wrong; size is going to be corrected anyway after the expansion,
so there is no need to do it here. This patch removes that redundant
correction.
To help find this bug, I heavily commented the routine; those comments
are included here as a bonus.
Signed-off-by: Andy Parkins <andyparkins@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
gitattributes.txt says, of the crlf attribute:
Set::
Setting the `crlf` attribute on a path is meant to mark
the path as a "text" file. 'core.autocrlf' conversion
takes place without guessing the content type by
inspection.
That is to say that the crlf attribute does not force the file to have
CRLF line endings, instead it removes the autocrlf guesswork and forces
the file to be treated as text. Then, whatever line ending is defined
by the autocrlf setting is applied.
However, that is not what convert.c was doing. The conversion to CRLF
was being skipped in crlf_to_worktree() when the following condition was
true:
action == CRLF_GUESS && auto_crlf <= 0
That is to say conversion took place when not in guess mode (crlf attribute
not specified) or core.autocrlf set to true. This was wrong. It meant
that the crlf attribute being on for a given file _forced_ CRLF
conversion, when actually it should force the file to be treated as
text, and converted accordingly. The real test should simply be
auto_crlf <= 0
That is to say, if core.autocrlf is falsei (or input), conversion from
LF to CRLF is never done. When core.autocrlf is true, conversion from
LF to CRLF is done only when in CRLF_GUESS (and the guess is "text"), or
CRLF_TEXT mode.
Similarly for crlf_to_worktree(), if core.autocrlf is false, no conversion
should _ever_ take place. In reality it was only not taking place if
core.autocrlf was false _and_ the crlf attribute was unspecified.
Signed-off-by: Andy Parkins <andyparkins@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
As noted by Johan Herland, git-archive is a kind of checkout and needs
to apply any checkout filters that might be configured.
This patch adds the convenience function convert_sha1_file which returns
a buffer containing the object's contents, after converting, if necessary
(i.e. it's a combination of read_sha1_file and convert_to_working_tree).
Direct calls to read_sha1_file in git-archive are then replaced by calls
to convert_sha1_file.
Since convert_sha1_file expects its path argument to be NUL-terminated --
a convention it inherits from convert_to_working_tree -- the patch also
changes the path handling in archive-tar.c to always NUL-terminate the
string. It used to solely rely on the len field of struct strbuf before.
archive-zip.c already NUL-terminates the path and thus needs no such
change.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <junkio@cox.net>
$Id$ is present already in SVN and CVS; it would mean that people
converting their existing repositories won't have to make any changes to
the source files should they want to make use of the ident attribute.
Given that it's a feature that's meant to calm those very people, it
seems obtuse to make them edit every file just to make use of it.
I think that bzr uses $Id$; Mercurial has examples hooks for $Id$;
monotone has $Id$ on its wishlist. I can't think of a good reason not
to stick with the de-facto standard and call ours $Id$ instead of
$ident$.
Signed-off-by: Andy Parkins <andyparkins@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
The interface is similar to the custom low-level merge drivers.
First you configure your filter driver by defining 'filter.<name>.*'
variables in the configuration.
filter.<name>.clean filter command to run upon checkin
filter.<name>.smudge filter command to run upon checkout
Then you assign filter attribute to each path, whose name
matches the custom filter driver's name.
Example:
(in .gitattributes)
*.c filter=indent
(in config)
[filter "indent"]
clean = indent
smudge = cat
Signed-off-by: Junio C Hamano <junkio@cox.net>