cat-file: support --textconv/--filters in batch mode

With this patch, --batch can be combined with --textconv or --filters.
For this to work, the input needs to have the form

	<object name><single white space><path>

so that the filters can be chosen appropriately.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 44 insertions, 5 deletions

diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 51f4c54..59dea48 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -17,6 +17,7 @@ struct batch_options {
 	int print_contents;
 	int buffer_output;
 	int all_objects;
+	int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
 	const char *format;
 };
 
@@ -280,7 +281,32 @@ static void print_object_or_die(struct batch_options *opt, struct expand_data *d
 	if (data->type == OBJ_BLOB) {
 		if (opt->buffer_output)
 			fflush(stdout);
-		if (stream_blob_to_fd(1, sha1, NULL, 0) < 0)
+		if (opt->cmdmode) {
+			char *contents;
+			unsigned long size;
+
+			if (!data->rest)
+				die("missing path for '%s'", sha1_to_hex(sha1));
+
+			if (opt->cmdmode == 'w') {
+				if (filter_object(data->rest, 0100644, sha1,
+						  &contents, &size))
+					die("could not convert '%s' %s",
+					    sha1_to_hex(sha1), data->rest);
+			} else if (opt->cmdmode == 'c') {
+				enum object_type type;
+				if (!textconv_object(data->rest, 0100644, sha1,
+						     1, &contents, &size))
+					contents = read_sha1_file(sha1, &type,
+								  &size);
+				if (!contents)
+					die("could not convert '%s' %s",
+					    sha1_to_hex(sha1), data->rest);
+			} else
+				die("BUG: invalid cmdmode: %c", opt->cmdmode);
+			batch_write(opt, contents, size);
+			free(contents);
+		} else if (stream_blob_to_fd(1, sha1, NULL, 0) < 0)
 			die("unable to stream %s to stdout", sha1_to_hex(sha1));
 	}
 	else {
@@ -417,6 +443,8 @@ static int batch_objects(struct batch_options *opt)
 	data.mark_query = 1;
 	strbuf_expand(&buf, opt->format, expand_format, &data);
 	data.mark_query = 0;
+	if (opt->cmdmode)
+		data.split_on_whitespace = 1;
 
 	if (opt->all_objects) {
 		struct object_info empty;
@@ -482,7 +510,7 @@ static int batch_objects(struct batch_options *opt)
 
 static const char * const cat_file_usage[] = {
 	N_("git cat-file (-t [--allow-unknown-type]|-s [--allow-unknown-type]|-e|-p|<type>|--textconv|--filters) [--path=<path>] <object>"),
-	N_("git cat-file (--batch | --batch-check) [--follow-symlinks]"),
+	N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv|--filters]"),
 	NULL
 };
 
@@ -553,7 +581,9 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 	argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 
 	if (opt) {
-		if (argc == 1)
+		if (batch.enabled && (opt == 'c' || opt == 'w'))
+			batch.cmdmode = opt;
+		else if (argc == 1)
 			obj_name = argv[0];
 		else
 			usage_with_options(cat_file_usage, options);
@@ -565,8 +595,12 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 		} else
 			usage_with_options(cat_file_usage, options);
 	}
-	if (batch.enabled && (opt || argc)) {
-		usage_with_options(cat_file_usage, options);
+	if (batch.enabled) {
+		if (batch.cmdmode != opt || argc)
+			usage_with_options(cat_file_usage, options);
+		if (batch.cmdmode && batch.all_objects)
+			die("--batch-all-objects cannot be combined with "
+			    "--textconv nor with --filters");
 	}
 
 	if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
@@ -578,6 +612,11 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 		usage_with_options(cat_file_usage, options);
 	}
 
+	if (force_path && batch.enabled) {
+		error("--path=<path> incompatible with --batch");
+		usage_with_options(cat_file_usage, options);
+	}
+
 	if (batch.buffer_output < 0)
 		batch.buffer_output = batch.all_objects;