[PATCH v3] convert filter: supply path to external driver

From

PWPete Wyckoff <pw@padd.com>

Date

Dec 21, 2010, 13:44 UTC

Message-ID

<20101221134403.GA10401@honk.padd.com>

In-Reply-To

<7v8vzkcol8.fsf@alter.siamese.dyndns.org>

    $File: //depot/product/dir/script.sh $

Signed-off-by: Pete Wyckoff <pw@padd.com>
---
gitster@pobox.com wrote on Mon, 20 Dec 2010 09:59 -0800:

> Another nitpick is if 's' is the right letter to use for the pathname
> information.  I think you took 's' after "string", but if this is to be
> extensible, you should anticipate that later there will be other kinds of
> information you may want to throw at the filters, and expect that some of
> them also will be of type "string", and you will have painted the person
> who wants to add that new information into a tight corner as you already
> took the valuable 's'.
> 
> Which would suggest that you shouldn't be naming the placeholder after the
> type but after what the placeholder means, no?  Perhaps %f (for filename)
> would be a better choice?

		-- Pete

 Documentation/gitattributes.txt |   12 ++++++++++
 convert.c                       |   22 +++++++++++++++++-
 t/t0021-conversion.sh           |   47 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 80 insertions(+), 1 deletions(-)

diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index 564586b..1afcf01 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -317,6 +317,18 @@ command is "cat").
 	smudge = cat
 ------------------------
 
+If your filter needs the path of the file it is working on,
+you can use the "%f" conversion specification.  It will be
+replaced with the relative path to the file.  This is important
+for keyword substitution that depends on the name of the
+file.  Like this:
+
+------------------------
+[filter "p4"]
+	clean = git-p4-filter --clean %f
+	smudge = git-p4-filter --smudge %f
+------------------------
+
 
 Interaction between checkin/checkout attributes
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/convert.c b/convert.c
index e41a31e..8f020bc 100644
--- a/convert.c
+++ b/convert.c
@@ -317,6 +317,7 @@ struct filter_params {
 	const char *src;
 	unsigned long size;
 	const char *cmd;
+	const char *path;
 };
 
 static int filter_buffer(int in, int out, void *data)
@@ -329,7 +330,23 @@ static int filter_buffer(int in, int out, void *data)
 	int write_err, status;
 	const char *argv[] = { NULL, NULL };
 
-	argv[0] = params->cmd;
+	/* apply % substitution to cmd */
+	struct strbuf cmd = STRBUF_INIT;
+	struct strbuf path = STRBUF_INIT;
+	struct strbuf_expand_dict_entry dict[] = {
+	    "f", NULL,
+	    NULL, NULL,
+	};
+
+	/* quote the path to preserve spaces, etc. */
+	sq_quote_buf(&path, params->path);
+	dict[0].value = path.buf;
+
+	/* expand all %f with the quoted path */
+	strbuf_expand(&cmd, params->cmd, strbuf_expand_dict_cb, &dict);
+	strbuf_release(&path);
+
+	argv[0] = cmd.buf;
 
 	memset(&child_process, 0, sizeof(child_process));
 	child_process.argv = argv;
@@ -349,6 +366,8 @@ static int filter_buffer(int in, int out, void *data)
 	status = finish_command(&child_process);
 	if (status)
 		error("external filter %s failed %d", params->cmd, status);
+
+	strbuf_release(&cmd);
 	return (write_err || status);
 }
 
@@ -376,6 +395,7 @@ static int apply_filter(const char *path, const char *src, size_t len,
 	params.src = src;
 	params.size = len;
 	params.cmd = cmd;
+	params.path = path;
 
 	fflush(NULL);
 	if (start_async(&async))
diff --git a/t/t0021-conversion.sh b/t/t0021-conversion.sh
index 828e35b..534a735 100755
--- a/t/t0021-conversion.sh
+++ b/t/t0021-conversion.sh
@@ -93,4 +93,51 @@ test_expect_success expanded_in_repo '
 	cmp expanded-keywords expected-output
 '
 
+cat <<EOF >argc.sh
+#!$SHELL_PATH
+echo argc: \$# "\$@"
+echo argc running >&2
+EOF
+chmod +x argc.sh
+
+#
+# The use of %f in a filter definition is expanded to the path to
+# the filename being smudged or cleaned.  It must be shell escaped.
+#
+test_expect_success 'shell-escaped filenames' '
+    norm=name-no-magic &&
+    spec=$(echo name:sgl\"dbl\ spc!bang | tr : \\047) &&
+    echo some test text > test
+    cat test > $norm &&
+    cat test > "$spec" &&
+    git add $norm &&
+    git add "$spec" &&
+    git commit -m "add files" &&
+
+    echo "name* filter=argc" > .gitattributes &&
+
+    # delete the files and check them out again, using the smudge filter
+    git config filter.argc.smudge "./argc.sh %f" &&
+    rm $norm "$spec" &&
+    git checkout -- $norm "$spec" &&
+
+    # make sure argc.sh counted the right number of args
+    echo "argc: 1 $norm" > res &&
+    cmp res $norm &&
+    echo "argc: 1 $spec" > res &&
+    cmp res "$spec" &&
+
+    # %f with other args
+    git config filter.argc.smudge "./argc.sh %f --myword" &&
+    rm $norm "$spec" &&
+    git checkout -- $norm "$spec" &&
+
+    # make sure argc.sh counted the right number of args
+    echo "argc: 2 $norm --myword" > res &&
+    cmp res $norm &&
+    echo "argc: 2 $spec --myword" > res &&
+    cmp res "$spec" &&
+    :
+'
+
 test_done

-- 
1.7.2.3