convert filter: supply path to external driver

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>

diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index 5a7f9364299cb4ed34a7dc35688c9bddcd35ff3d..22b85825abcd48604701b8ceae7fef28e026ddde 100644 (file)
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -335,6 +335,16 @@ input that is already correctly indented.  In this case, the lack of a
 smudge filter means that the clean filter _must_ accept its own output
 without modifying it.
 
+Sequence "%f" on the filter command line is replaced with the name of
+the file the filter is working on.  A filter might use this in keyword
+substitution.  For example:
+
+------------------------
+[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 01de9a84c21b31a0120065a32a386f27321cdf7b..d5aebed48df3387e966a23b6ee460dc2244f728e 100644 (file)
--- a/convert.c
+++ b/convert.c
@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "attr.h"
 #include "run-command.h"
+#include "quote.h"
 
 /*
  * convert.c - convert a file when checking it out and checking it in.
@@ -318,6 +319,7 @@ 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)
@@ -330,7 +332,23 @@ 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;
@@ -350,6 +368,8 @@ 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);
 }
 
@@ -377,6 +397,7 @@ 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 828e35baf72d94908ad1f30dbd2e1aa6f9376e69..aacfd004b1f2908f955dc7d89dd64b9db35ade19 100755 (executable)
--- a/t/t0021-conversion.sh
+++ b/t/t0021-conversion.sh
@@ -93,4 +93,46 @@ test_expect_success expanded_in_repo '
        cmp expanded-keywords expected-output
 '
 
+# 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.
+# First, set up some interesting file names and pet them in
+# .gitattributes.
+test_expect_success 'filter shell-escaped filenames' '
+       cat >argc.sh <<-EOF &&
+       #!$SHELL_PATH
+       echo argc: \$# "\$@"
+       EOF
+       normal=name-no-magic &&
+       special="name  with '\''sq'\'' and \$x" &&
+       echo some test text >"$normal" &&
+       echo some test text >"$special" &&
+       git add "$normal" "$special" &&
+       git commit -q -m "add files" &&
+       echo "name* filter=argc" >.gitattributes &&
+
+       # delete the files and check them out again, using a smudge filter
+       # that will count the args and echo the command-line back to us
+       git config filter.argc.smudge "sh ./argc.sh %f" &&
+       rm "$normal" "$special" &&
+       git checkout -- "$normal" "$special" &&
+
+       # make sure argc.sh counted the right number of args
+       echo "argc: 1 $normal" >expect &&
+       test_cmp expect "$normal" &&
+       echo "argc: 1 $special" >expect &&
+       test_cmp expect "$special" &&
+
+       # do the same thing, but with more args in the filter expression
+       git config filter.argc.smudge "sh ./argc.sh %f --my-extra-arg" &&
+       rm "$normal" "$special" &&
+       git checkout -- "$normal" "$special" &&
+
+       # make sure argc.sh counted the right number of args
+       echo "argc: 2 $normal --my-extra-arg" >expect &&
+       test_cmp expect "$normal" &&
+       echo "argc: 2 $special --my-extra-arg" >expect &&
+       test_cmp expect "$special" &&
+       :
+'
+
 test_done