[PATCH v2 3/4] bundle: keep a copy of bundle file name in the in-core bundle header

[Junio C Hamano <gitster@pobox.com>]

This will be necessary when we start reading from a split bundle
where the header and the thin-pack data live in different files.

The in-core bundle header will read from a file that has the header,
and will record the path to that file.  We would find the name of
the file that hosts the thin-pack data from the header, and we would
take that name as relative to the file we read the header from.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/bundle.c |  6 +++---
 bundle.c         | 27 +++++++++++++++++----------
 bundle.h         |  4 +++-
 transport.c      |  3 ++-
 4 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/builtin/bundle.c b/builtin/bundle.c
index 4883a43..c9ede65 100644
--- a/builtin/bundle.c
+++ b/builtin/bundle.c
@@ -35,9 +35,9 @@ int cmd_bundle(int argc, const char **argv, const char *prefix)
 		bundle_file = buffer;
 	}
 
-	memset(&header, 0, sizeof(header));
-	if (strcmp(cmd, "create") && (bundle_fd =
-				read_bundle_header(bundle_file, &header)) < 0)
+	init_bundle_header(&header, bundle_file);
+	if (strcmp(cmd, "create") &&
+	    (bundle_fd = read_bundle_header(&header)) < 0)
 		return 1;
 
 	if (!strcmp(cmd, "verify")) {
diff --git a/bundle.c b/bundle.c
index 9c5a6f0..32bdb01 100644
--- a/bundle.c
+++ b/bundle.c
@@ -21,8 +21,13 @@ static void add_to_ref_list(const unsigned char *sha1, const char *name,
 	list->nr++;
 }
 
-static int parse_bundle_header(int fd, struct bundle_header *header,
-			       const char *report_path)
+void init_bundle_header(struct bundle_header *header, const char *name)
+{
+	memset(header, '\0', sizeof(*header));
+	header->filename = xstrdup(name);
+}
+
+static int parse_bundle_header(int fd, struct bundle_header *header, int quiet)
 {
 	struct strbuf buf = STRBUF_INIT;
 	int status = 0;
@@ -30,9 +35,9 @@ static int parse_bundle_header(int fd, struct bundle_header *header,
 	/* The bundle header begins with the signature */
 	if (strbuf_getwholeline_fd(&buf, fd, '\n') ||
 	    strcmp(buf.buf, bundle_signature)) {
-		if (report_path)
+		if (!quiet)
 			error(_("'%s' does not look like a v2 bundle file"),
-			      report_path);
+			      header->filename);
 		status = -1;
 		goto abort;
 	}
@@ -57,7 +62,7 @@ static int parse_bundle_header(int fd, struct bundle_header *header,
 		if (get_sha1_hex(buf.buf, sha1) ||
 		    (buf.len > 40 && !isspace(buf.buf[40])) ||
 		    (!is_prereq && buf.len <= 40)) {
-			if (report_path)
+			if (!quiet)
 				error(_("unrecognized header: %s%s (%d)"),
 				      (is_prereq ? "-" : ""), buf.buf, (int)buf.len);
 			status = -1;
@@ -79,13 +84,13 @@ static int parse_bundle_header(int fd, struct bundle_header *header,
 	return fd;
 }
 
-int read_bundle_header(const char *path, struct bundle_header *header)
+int read_bundle_header(struct bundle_header *header)
 {
-	int fd = open(path, O_RDONLY);
+	int fd = open(header->filename, O_RDONLY);
 
 	if (fd < 0)
-		return error(_("could not open '%s'"), path);
-	return parse_bundle_header(fd, header, path);
+		return error(_("could not open '%s'"), header->filename);
+	return parse_bundle_header(fd, header, 0);
 }
 
 int is_bundle(const char *path, int quiet)
@@ -96,7 +101,7 @@ int is_bundle(const char *path, int quiet)
 	if (fd < 0)
 		return 0;
 	memset(&header, 0, sizeof(header));
-	fd = parse_bundle_header(fd, &header, quiet ? NULL : path);
+	fd = parse_bundle_header(fd, &header, quiet);
 	if (fd >= 0)
 		close(fd);
 	return (fd >= 0);
@@ -112,6 +117,8 @@ void release_bundle_header(struct bundle_header *header)
 	for (i = 0; i < header->references.nr; i++)
 		free(header->references.list[i].name);
 	free(header->references.list);
+
+	free((void *)header->filename);
 }
 
 static int list_refs(struct ref_list *r, int argc, const char **argv)
diff --git a/bundle.h b/bundle.h
index f7ce23b..e059ccf 100644
--- a/bundle.h
+++ b/bundle.h
@@ -10,12 +10,14 @@ struct ref_list {
 };
 
 struct bundle_header {
+	const char *filename;
 	struct ref_list prerequisites;
 	struct ref_list references;
 };
 
 int is_bundle(const char *path, int quiet);
-int read_bundle_header(const char *path, struct bundle_header *header);
+void init_bundle_header(struct bundle_header *, const char *filename);
+int read_bundle_header(struct bundle_header *header);
 int create_bundle(struct bundle_header *header, const char *path,
 		int argc, const char **argv);
 int verify_bundle(struct bundle_header *header, int verbose);
diff --git a/transport.c b/transport.c
index 08e15c5..7bd3206 100644
--- a/transport.c
+++ b/transport.c
@@ -81,7 +81,8 @@ static struct ref *get_refs_from_bundle(struct transport *transport, int for_pus
 
 	if (data->fd > 0)
 		close(data->fd);
-	data->fd = read_bundle_header(transport->url, &data->header);
+	init_bundle_header(&data->header, transport->url);
+	data->fd = read_bundle_header(&data->header);
 	if (data->fd < 0)
 		die ("Could not read bundle '%s'.", transport->url);
 	for (i = 0; i < data->header.references.nr; i++) {
-- 
2.8.0-rc0-114-g0b3e5e5