From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
Introduce the ability to have missing objects in a repo. This
functionality is guarded by new repository extension options:
`extensions.partialcloneremote` and
`extensions.partialclonefilter`.
See the update to Documentation/technical/repository-version.txt
in this patch for more information.
Signed-off-by: Jonathan Tan <jonathantanmy@xxxxxxxxxx>
Signed-off-by: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
---
Documentation/technical/repository-version.txt | 22 ++++++++
Makefile | 1 +
cache.h | 4 ++
config.h | 3 +
environment.c | 2 +
partial-clone-utils.c | 78 ++++++++++++++++++++++++++
partial-clone-utils.h | 34 +++++++++++
setup.c | 15 +++++
8 files changed, 159 insertions(+)
create mode 100644 partial-clone-utils.c
create mode 100644 partial-clone-utils.h
diff --git a/Documentation/technical/repository-version.txt b/Documentation/technical/repository-version.txt
index 00ad379..9d488db 100644
--- a/Documentation/technical/repository-version.txt
+++ b/Documentation/technical/repository-version.txt
@@ -86,3 +86,25 @@ for testing format-1 compatibility.
When the config key `extensions.preciousObjects` is set to `true`,
objects in the repository MUST NOT be deleted (e.g., by `git-prune` or
`git repack -d`).
+
+`partialcloneremote`
+~~~~~~~~~~~~~~~~~~~~
+
+When the config key `extensions.partialcloneremote` is set, it indicates
+that the repo was created with a partial clone (or later performed
+a partial fetch) and that the remote may have omitted sending
+certain unwanted objects. Such a remote is called a "promisor remote"
+and it promises that all such omitted objects can be fetched from it
+in the future.
+
+The value of this key is the name of the promisor remote.
+
+`partialclonefilter`
+~~~~~~~~~~~~~~~~~~~~
+
+When the config key `extensions.partialclonefilter` is set, it gives
+the initial filter expression used to create the partial clone.
+This value becomed the default filter expression for subsequent
+fetches (called "partial fetches") from the promisor remote. This
+value may also be set by the first explicit partial fetch following a
+normal clone.
diff --git a/Makefile b/Makefile
index ca378a4..12d141a 100644
--- a/Makefile
+++ b/Makefile
@@ -838,6 +838,7 @@ LIB_OBJS += pack-write.o
LIB_OBJS += pager.o
LIB_OBJS += parse-options.o
LIB_OBJS += parse-options-cb.o
+LIB_OBJS += partial-clone-utils.o
LIB_OBJS += patch-delta.o
LIB_OBJS += patch-ids.o
LIB_OBJS += path.o
diff --git a/cache.h b/cache.h
index 6440e2b..4b785c0 100644
--- a/cache.h
+++ b/cache.h
@@ -860,12 +860,16 @@ extern int grafts_replace_parents;
#define GIT_REPO_VERSION 0
#define GIT_REPO_VERSION_READ 1
extern int repository_format_precious_objects;
+extern char *repository_format_partial_clone_remote;
+extern char *repository_format_partial_clone_filter;
struct repository_format {
int version;
int precious_objects;
int is_bare;
char *work_tree;
+ char *partial_clone_remote; /* value of extensions.partialcloneremote */
+ char *partial_clone_filter; /* value of extensions.partialclonefilter */
struct string_list unknown_extensions;
};
diff --git a/config.h b/config.h
index a49d264..90544ef 100644
--- a/config.h
+++ b/config.h
@@ -34,6 +34,9 @@ struct config_options {
const char *git_dir;
};
+#define KEY_PARTIALCLONEREMOTE "partialcloneremote"
+#define KEY_PARTIALCLONEFILTER "partialclonefilter"
+
typedef int (*config_fn_t)(const char *, const char *, void *);
extern int git_default_config(const char *, const char *, void *);
extern int git_config_from_file(config_fn_t fn, const char *, void *);
diff --git a/environment.c b/environment.c
index 8289c25..2fcf9bb 100644
--- a/environment.c
+++ b/environment.c
@@ -27,6 +27,8 @@ int warn_ambiguous_refs = 1;
int warn_on_object_refname_ambiguity = 1;
int ref_paranoia = -1;
int repository_format_precious_objects;
+char *repository_format_partial_clone_remote;
+char *repository_format_partial_clone_filter;
const char *git_commit_encoding;
const char *git_log_output_encoding;
const char *apply_default_whitespace;
diff --git a/partial-clone-utils.c b/partial-clone-utils.c
new file mode 100644
index 0000000..32cc20d
--- /dev/null
+++ b/partial-clone-utils.c
@@ -0,0 +1,78 @@
+#include "cache.h"
+#include "config.h"
+#include "partial-clone-utils.h"
+
+int is_partial_clone_registered(void)
+{
+ if (repository_format_partial_clone_remote ||
+ repository_format_partial_clone_filter)
+ return 1;
+
+ return 0;
+}
+
+void partial_clone_utils_register(
+ const struct list_objects_filter_options *filter_options,
+ const char *remote,
+ const char *cmd_name)
+{
+ if (is_partial_clone_registered()) {
+ /*
+ * The original partial-clone or a previous partial-fetch
+ * already registered the partial-clone settings.
+ * If we get here, we are in a subsequent partial-* command
+ * (with explicit filter args on the command line).
+ *
+ * For now, we restrict subsequent commands to one
+ * consistent with the original request. We may relax
+ * this later after we get more experience with the
+ * partial-clone feature.
+ *
+ * [] Restrict to same remote because our dynamic
+ * object loading only knows how to fetch objects
+ * from 1 remote.
+ */
+ assert(filter_options && filter_options->choice);
+ assert(remote && *remote);
+
+ if (strcmp(remote, repository_format_partial_clone_remote))
+ die("%s --%s currently limited to remote '%s'",
+ cmd_name, CL_ARG__FILTER,
+ repository_format_partial_clone_remote);
+
+ /*
+ * Treat the (possibly new) filter-spec as transient;
+ * use it for the current command, but do not overwrite
+ * the default.
+ */
+ return;
+ }
+
+ repository_format_partial_clone_remote = xstrdup(remote);
+ repository_format_partial_clone_filter = xstrdup(filter_options->raw_value);
+
+ /*
+ * Force repo version > 0 to enable extensions namespace.
+ *
+ * TODO if already set > 0, we should not overwrite it.
+ */
+ git_config_set("core.repositoryformatversion", "1");
+
+ /*
+ * Use the "extensions" namespace in the config to record
+ * the name of the remote used in the partial clone.
+ * This will help us return to that server when we need
+ * to backfill missing objects.
+ *
+ * It is also used to indicate that there *MAY* be
+ * missing objects so that subsequent commands don't
+ * immediately die if they hit one.
+ *
+ * Also remember the initial filter settings used by
+ * clone as a default for future fetches.
+ */
+ git_config_set("extensions." KEY_PARTIALCLONEREMOTE,
+ repository_format_partial_clone_remote);
+ git_config_set("extensions." KEY_PARTIALCLONEFILTER,
+ repository_format_partial_clone_filter);
+}
diff --git a/partial-clone-utils.h b/partial-clone-utils.h
new file mode 100644
index 0000000..b527570
--- /dev/null
+++ b/partial-clone-utils.h
@@ -0,0 +1,34 @@
+#ifndef PARTIAL_CLONE_UTILS_H
+#define PARTIAL_CLONE_UTILS_H
+
+#include "list-objects-filter-options.h"
+
+/*
+ * Register that partial-clone was used to create the repo and
+ * update the config on disk.
+ *
+ * If nothing else, this indicates that the ODB may have missing
+ * objects and that various commands should handle that gracefully.
+ *
+ * Record the remote used for the clone so that we know where
+ * to get missing objects in the future.
+ *
+ * Also record the filter expression so that we know something
+ * about the missing objects (e.g., size-limit vs sparse).
+ *
+ * May also be used by a partial-fetch following a normal clone
+ * to turn on the above tracking.
+ */
+extern void partial_clone_utils_register(
+ const struct list_objects_filter_options *filter_options,
+ const char *remote,
+ const char *cmd_name);
+
+/*
+ * Return 1 if partial-clone was used to create the repo
+ * or a subsequent partial-fetch was used. This is an
+ * indicator that there may be missing objects.
+ */
+extern int is_partial_clone_registered(void);
+
+#endif /* PARTIAL_CLONE_UTILS_H */
diff --git a/setup.c b/setup.c
index 03f51e0..bc4133d 100644
--- a/setup.c
+++ b/setup.c
@@ -420,6 +420,19 @@ static int check_repo_format(const char *var, const char *value, void *vdata)
;
else if (!strcmp(ext, "preciousobjects"))
data->precious_objects = git_config_bool(var, value);
+
+ else if (!strcmp(ext, KEY_PARTIALCLONEREMOTE))
+ if (!value)
+ return config_error_nonbool(var);
+ else
+ data->partial_clone_remote = xstrdup(value);
+
+ else if (!strcmp(ext, KEY_PARTIALCLONEFILTER))
+ if (!value)
+ return config_error_nonbool(var);
+ else
+ data->partial_clone_filter = xstrdup(value);
+
else
string_list_append(&data->unknown_extensions, ext);
} else if (strcmp(var, "core.bare") == 0) {
@@ -463,6 +476,8 @@ static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
}
repository_format_precious_objects = candidate.precious_objects;
+ repository_format_partial_clone_remote = candidate.partial_clone_remote;
+ repository_format_partial_clone_filter = candidate.partial_clone_filter;
string_list_clear(&candidate.unknown_extensions, 0);
if (!has_common) {
if (candidate.is_bare != -1) {
--
2.9.3
