Pushing from a shallow clone using today's send-pack and receive-pack
may work, if the transferred pack does not end up at any graft
points. If it does, recent receive-pack that does connectivity check
will reject the push. If receive-pack is old and does not have the
connectivity check, the upstream repo becomes corrupt.
The pack protocol is updated and send-pack now sends all shallow
grafts before it sends the commands, if the repo is shallow. This
protocol extension will break current receive-pack, which is intended,
mostly to stop corrupting the upstream repo.
Changes on the receiver are similar to what has been done in
fetch-pack, i.e. filter out refs that require new shallow roots then
go along as usual.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx>
---
Documentation/technical/pack-protocol.txt | 4 +-
builtin/receive-pack.c | 68 +++++++++++++++++++++++++++++-
builtin/send-pack.c | 2 +-
send-pack.c | 3 ++
t/t5537-push-shallow.sh (new +x) | 70 +++++++++++++++++++++++++++++++
5 files changed, 143 insertions(+), 4 deletions(-)
create mode 100755 t/t5537-push-shallow.sh
diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index eb8edd1..c73b62f 100644
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -464,7 +464,9 @@ contain all the objects that the server will need to complete the new
references.
----
- update-request = command-list [pack-file]
+ update-request = *shallow command-list [pack-file]
+
+ shallow = PKT-LINE("shallow" SP obj-id)
command-list = PKT-LINE(command NUL capability-list LF)
*PKT-LINE(command LF)
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 22e162d..254feff 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -43,6 +43,9 @@ static int fix_thin = 1;
static const char *head_name;
static void *head_name_to_free;
static int sent_capabilities;
+static int shallow_push;
+static const char* alternate_shallow_file;
+static struct extra_have_objects shallow;
static enum deny_action parse_deny_action(const char *var, const char *value)
{
@@ -189,6 +192,7 @@ struct command {
const char *error_string;
unsigned int skip_update:1,
did_not_exist:1;
+ int index;
unsigned char old_sha1[20];
unsigned char new_sha1[20];
char ref_name[FLEX_ARRAY]; /* more */
@@ -687,7 +691,7 @@ static int iterate_receive_command_list(void *cb_data, unsigned char sha1[20])
struct command *cmd = *cmd_list;
while (cmd) {
- if (!is_null_sha1(cmd->new_sha1)) {
+ if (!is_null_sha1(cmd->new_sha1) && !cmd->skip_update) {
hashcpy(sha1, cmd->new_sha1);
*cmd_list = cmd->next;
return 0;
@@ -712,8 +716,25 @@ static void reject_updates_to_hidden(struct command *commands)
}
}
+static void filter_shallow_refs(struct command *commands,
+ const int *ref_status, int nr_ref)
+{
+ struct command *cmd;
+ for (cmd = commands; cmd; cmd = cmd->next)
+ if (!is_null_sha1(cmd->new_sha1) && ref_status[cmd->index]) {
+ cmd->error_string = "shallow update not allowed";
+ cmd->skip_update = 1;
+ }
+ if (*alternate_shallow_file) {
+ unlink(alternate_shallow_file);
+ alternate_shallow_file = NULL;
+ }
+}
+
static void execute_commands(struct command *commands, const char *unpacker_error)
{
+ int *ref_status = NULL;
+ struct extra_have_objects ref;
struct command *cmd;
unsigned char sha1[20];
@@ -723,6 +744,20 @@ static void execute_commands(struct command *commands, const char *unpacker_erro
return;
}
+ memset(&ref, 0, sizeof(ref));
+ if (shallow_push) {
+ int i;
+ for (i = 0, cmd = commands; cmd; i++, cmd = cmd->next)
+ if (!is_null_sha1(cmd->new_sha1)) {
+ add_extra_have(&ref, cmd->new_sha1);
+ cmd->index = i;
+ }
+
+ ref_status = xmalloc(sizeof(*ref_status) * ref.nr);
+ if (mark_new_shallow_refs(&ref, ref_status, NULL, &shallow))
+ filter_shallow_refs(commands, ref_status, ref.nr);
+ }
+
cmd = commands;
if (check_everything_connected(iterate_receive_command_list,
0, &cmd))
@@ -752,6 +787,8 @@ static void execute_commands(struct command *commands, const char *unpacker_erro
cmd->error_string = update(cmd);
}
+ free(ref.array);
+ free(ref_status);
}
static struct command *read_head_info(void)
@@ -768,6 +805,15 @@ static struct command *read_head_info(void)
line = packet_read_line(0, &len);
if (!line)
break;
+
+ if (len == 48 && !prefixcmp(line, "shallow ")) {
+ if (get_sha1_hex(line + 8, old_sha1))
+ die("protocol error: expected shallow sha, got '%s'", line + 8);
+ add_extra_have(&shallow, old_sha1);
+ shallow_push = 1;
+ continue;
+ }
+
if (len < 83 ||
line[40] != ' ' ||
line[81] != ' ' ||
@@ -822,7 +868,7 @@ static const char *pack_lockfile;
static const char *unpack(int err_fd)
{
struct pack_header hdr;
- const char *argv[7];
+ const char *argv[9];
const char *hdr_err;
int status, ac = 0;
char hdr_arg[38];
@@ -843,6 +889,24 @@ static const char *unpack(int err_fd)
"--pack_header=%"PRIu32",%"PRIu32,
ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
+ if (shallow_push) {
+ struct extra_have_objects extra;
+ memset(&extra, 0, sizeof(extra));
+ remove_reachable_shallow_points(&extra, &shallow);
+ if (extra.nr) {
+ alternate_shallow_file = setup_temporary_shallow(&extra);
+ free(shallow.array);
+ shallow = extra;
+ } else {
+ alternate_shallow_file = NULL;
+ shallow_push = 0;
+ }
+ if (alternate_shallow_file && *alternate_shallow_file) {
+ argv[ac++] = "--shallow-file";
+ argv[ac++] = alternate_shallow_file;
+ }
+ }
+
memset(&child, 0, sizeof(child));
if (ntohl(hdr.hdr_entries) < unpack_limit) {
argv[ac++] = "unpack-objects";
diff --git a/builtin/send-pack.c b/builtin/send-pack.c
index bfa9253..5db1311 100644
--- a/builtin/send-pack.c
+++ b/builtin/send-pack.c
@@ -207,7 +207,7 @@ int cmd_send_pack(int argc, const char **argv, const char *prefix)
(send_all && args.send_mirror))
usage(send_pack_usage);
- if (is_repository_shallow())
+ if (is_repository_shallow() && args.stateless_rpc)
die("attempt to push from a shallow repository");
if (remote_name) {
diff --git a/send-pack.c b/send-pack.c
index fab62e3..8b5571c 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -213,6 +213,9 @@ int send_pack(struct send_pack_args *args,
return 0;
}
+ if (!args->dry_run)
+ advertise_shallow_grafts(out);
+
/*
* Finally, tell the other end!
*/
diff --git a/t/t5537-push-shallow.sh b/t/t5537-push-shallow.sh
new file mode 100755
index 0000000..650c31a
--- /dev/null
+++ b/t/t5537-push-shallow.sh
@@ -0,0 +1,70 @@
+#!/bin/sh
+
+test_description='push from/to a shallow clone'
+
+. ./test-lib.sh
+
+commit() {
+ echo "$1" >tracked &&
+ git add tracked &&
+ git commit -m "$1"
+}
+
+test_expect_success 'setup' '
+ git config --global transfer.fsckObjects true &&
+ commit 1 &&
+ commit 2 &&
+ commit 3 &&
+ commit 4 &&
+ (
+ git init full-abc &&
+ cd full-abc &&
+ commit a &&
+ commit b &&
+ commit c
+ ) &&
+ git clone --no-local --depth=2 .git shallow &&
+ git --git-dir=shallow/.git log --format=%s >actual &&
+ cat <<EOF >expect &&
+4
+3
+EOF
+ test_cmp expect actual &&
+ git clone --no-local --depth=2 full-abc/.git shallow2 &&
+ git --git-dir=shallow2/.git log --format=%s >actual &&
+ cat <<EOF >expect &&
+c
+b
+EOF
+ test_cmp expect actual
+'
+
+test_expect_success 'push from shallow clone' '
+ (
+ cd shallow &&
+ commit 5 &&
+ git push ../.git +master:refs/remotes/shallow/master
+ ) &&
+ git log --format=%s shallow/master >actual &&
+ git fsck &&
+ cat <<EOF >expect &&
+5
+4
+3
+2
+1
+EOF
+ test_cmp expect actual
+'
+
+test_expect_success 'push from shallow clone, with grafted roots' '
+ (
+ cd shallow2 &&
+ test_must_fail git push ../.git +master:refs/remotes/shallow2/master 2>err &&
+ grep "shallow2/master.*shallow update not allowed" err
+ ) &&
+ test_must_fail git rev-parse shallow2/master &&
+ git fsck
+'
+
+test_done
--
1.8.2.83.gc99314b
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html