[PATCH] submodule: truncate the oid when fetchig commits
- From
Michael Schroeder <mls@suse.de>
- Date
- Aug 14, 2025, 15:06 UTC
- Message-ID
- <aJ37eHEGMw6RgmZC@suse.de>
If a submodule uses a different hash algorithm than used in the main repository, the recorded submodule commit is padded with zeros. This is usually not a problem as the default is to do submodule clones non-shallow and the commit can be found in the local objects.
But this is not true if the --shallow-submodules clone option is used (or the --depth option in the submodule update call). In this case, the commit is often not reachable and a fetch of the specific commit is done. But the fetch cannot deal with the zero padding and interprets the commit as a name. Because of this, the checkout will fail.
Implement truncation of the recorded commit to the correct size corresponding to the hash algorithm used in the submodule.
Signed-off-by: Michael Schroeder <mls@suse.de> --- builtin/submodule--helper.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c index 07a1935cbe..ef21eb42b8 100644 --- a/builtin/submodule--helper.c +++ b/builtin/submodule--helper.c @@ -72,7 +72,7 @@ static char *resolve_relative_url(const char *rel_url, const char *up_path, int return resolved_url; } -static int get_default_remote_submodule(const char *module_path, char **default_remote) +static int get_default_remote_submodule(const char *module_path, char **default_remote, const struct git_hash_algo **hash_algo) { const struct submodule *sub; struct repository subrepo; @@ -106,6 +106,9 @@ static int get_default_remote_submodule(const char *module_path, char **default_ *default_remote = xstrdup(remote_name); + if (hash_algo) + *hash_algo = subrepo.hash_algo; + repo_clear(&subrepo); free(url); @@ -1272,7 +1275,7 @@ static void sync_submodule(const char *path, const char *prefix, goto cleanup; strbuf_reset(&sb); - code = get_default_remote_submodule(path, &default_remote); + code = get_default_remote_submodule(path, &default_remote, NULL); if (code) exit(code); @@ -2319,16 +2322,19 @@ static int fetch_in_submodule(const char *module_path, int depth, int quiet, if (depth) strvec_pushf(&cp.args, "--depth=%d", depth); if (oid) { - char *hex = oid_to_hex(oid); + char hexbuffer[GIT_MAX_HEXSZ + 1]; + char *hex = oid_to_hex_r(hexbuffer, oid); char *remote; + const struct git_hash_algo *hash_algo = NULL; int code; - code = get_default_remote_submodule(module_path, &remote); + code = get_default_remote_submodule(module_path, &remote, &hash_algo); if (code) { child_process_clear(&cp); return code; } - + if (hash_algo) + hex[hash_algo->hexsz] = 0; /* truncate to correct size */ strvec_pushl(&cp.args, remote, hex, NULL); free(remote); } @@ -2635,7 +2641,7 @@ static int update_submodule(struct update_data *update_data) char *remote_ref; int code; - code = get_default_remote_submodule(update_data->sm_path, &remote_name); + code = get_default_remote_submodule(update_data->sm_path, &remote_name, NULL); if (code) return code; code = remote_submodule_branch(update_data->sm_path, &branch);
-- 2.50.0