bundle: parse filter capability

The v3 bundle format has capabilities, allowing newer versions of Git to
create bundles with newer features. Older versions that do not
understand these new capabilities will fail with a helpful warning.

Create a new capability allowing Git to understand that the contained
pack-file is filtered according to some object filter. Typically, this
filter will be "blob:none" for a blobless partial clone.

This change teaches Git to parse this capability, place its value in the
bundle header, and demonstrate this understanding by adding a message to
'git bundle verify'.

Since we will use gently_parse_list_objects_filter() outside of
list-objects-filter-options.c, make it an external method and move its
API documentation to before its declaration.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-bundle.txt b/Documentation/git-bundle.txt
index 72ab81390525cd23aa8b63a43d0070986620db17..ac4c4352aae8ae12bdaf9f10413eb6ac12a7eb6d 100644 (file)
--- a/Documentation/git-bundle.txt
+++ b/Documentation/git-bundle.txt
@@ -75,8 +75,11 @@ verify <file>::
        cleanly to the current repository.  This includes checks on the
        bundle format itself as well as checking that the prerequisite
        commits exist and are fully linked in the current repository.
-       'git bundle' prints a list of missing commits, if any, and exits
-       with a non-zero status.
+       Information about additional capabilities, such as "object filter",
+       is printed. See "Capabilities" in link:technical/bundle-format.html
+       for more information. Finally, 'git bundle' prints a list of
+       missing commits, if any. The exit code is zero for success, but
+       will be nonzero if the bundle file is invalid.
 
 list-heads <file>::
        Lists the references defined in the bundle.  If followed by a

diff --git a/Documentation/technical/bundle-format.txt b/Documentation/technical/bundle-format.txt
index bac558d049a36f4b4fbb132c7aa1dd5af4770102..b9be8644cf5d53161b7190f580be935b28d402a3 100644 (file)
--- a/Documentation/technical/bundle-format.txt
+++ b/Documentation/technical/bundle-format.txt
@@ -71,6 +71,11 @@ and the Git bundle v2 format cannot represent a shallow clone repository.
 == Capabilities
 
 Because there is no opportunity for negotiation, unknown capabilities cause 'git
-bundle' to abort.  The only known capability is `object-format`, which specifies
-the hash algorithm in use, and can take the same values as the
-`extensions.objectFormat` configuration value.
+bundle' to abort.
+
+* `object-format` specifies the hash algorithm in use, and can take the same
+  values as the `extensions.objectFormat` configuration value.
+
+* `filter` specifies an object filter as in the `--filter` option in
+  linkgit:git-rev-list[1]. The resulting pack-file must be marked as a
+  `.promisor` pack-file after it is unbundled.

diff --git a/bundle.c b/bundle.c
index 7ba60a573d73c92a02ab609bc67203d6032b6658..41e75efab9a293ad21745d0b567ba2bc12905b62 100644 (file)
--- a/bundle.c
+++ b/bundle.c
@@ -11,7 +11,7 @@
 #include "run-command.h"
 #include "refs.h"
 #include "strvec.h"
-
+#include "list-objects-filter-options.h"
 
 static const char v2_bundle_signature[] = "# v2 git bundle\n";
 static const char v3_bundle_signature[] = "# v3 git bundle\n";
@@ -33,6 +33,7 @@ void bundle_header_release(struct bundle_header *header)
 {
        string_list_clear(&header->prerequisites, 1);
        string_list_clear(&header->references, 1);
+       list_objects_filter_release(&header->filter);
 }
 
 static int parse_capability(struct bundle_header *header, const char *capability)
@@ -45,6 +46,10 @@ static int parse_capability(struct bundle_header *header, const char *capability
                header->hash_algo = &hash_algos[algo];
                return 0;
        }
+       if (skip_prefix(capability, "filter=", &arg)) {
+               parse_list_objects_filter(&header->filter, arg);
+               return 0;
+       }
        return error(_("unknown capability '%s'"), capability);
 }
 
@@ -220,6 +225,8 @@ int verify_bundle(struct repository *r,
        req_nr = revs.pending.nr;
        setup_revisions(2, argv, &revs, NULL);
 
+       list_objects_filter_copy(&revs.filter, &header->filter);
+
        if (prepare_revision_walk(&revs))
                die(_("revision walk setup failed"));
 
@@ -259,6 +266,12 @@ int verify_bundle(struct repository *r,
                             r->nr),
                          r->nr);
                list_refs(r, 0, NULL);
+
+               if (header->filter.choice) {
+                       printf_ln("The bundle uses this filter: %s",
+                                 list_objects_filter_spec(&header->filter));
+               }
+
                r = &header->prerequisites;
                if (!r->nr) {
                        printf_ln(_("The bundle records a complete history."));

diff --git a/bundle.h b/bundle.h
index 06009fe6b1f00b939350ba88ba7bf8f72565de4c..7fef2108f436861726ca4efb6937f9d434e61d7e 100644 (file)
--- a/bundle.h
+++ b/bundle.h
@@ -4,12 +4,14 @@
 #include "strvec.h"
 #include "cache.h"
 #include "string-list.h"
+#include "list-objects-filter-options.h"
 
 struct bundle_header {
        unsigned version;
        struct string_list prerequisites;
        struct string_list references;
        const struct git_hash_algo *hash_algo;
+       struct list_objects_filter_options filter;
 };
 
 #define BUNDLE_HEADER_INIT \

diff --git a/list-objects-filter-options.c b/list-objects-filter-options.c
index 449d53af69f466d73aa8fd8cfd2c7e1f2743dcf7..f02d8df1422f61077dc9e032befe68e755e88c56 100644 (file)
--- a/list-objects-filter-options.c
+++ b/list-objects-filter-options.c
@@ -40,22 +40,7 @@ const char *list_object_filter_config_name(enum list_objects_filter_choice c)
        BUG("list_object_filter_config_name: invalid argument '%d'", c);
 }
 
-/*
- * Parse value of the argument to the "filter" keyword.
- * On the command line this looks like:
- *       --filter=<arg>
- * and in the pack protocol as:
- *       "filter" SP <arg>
- *
- * The filter keyword will be used by many commands.
- * See Documentation/rev-list-options.txt for allowed values for <arg>.
- *
- * Capture the given arg as the "filter_spec".  This can be forwarded to
- * subordinate commands when necessary (although it's better to pass it through
- * expand_list_objects_filter_spec() first).  We also "intern" the arg for the
- * convenience of the current command.
- */
-static int gently_parse_list_objects_filter(
+int gently_parse_list_objects_filter(
        struct list_objects_filter_options *filter_options,
        const char *arg,
        struct strbuf *errbuf)

diff --git a/list-objects-filter-options.h b/list-objects-filter-options.h
index 425c38cae9da43830e92965c1b3904c4f52b94ae..2eb6c983949db0354b0041f10c36e24dc2885116 100644 (file)
--- a/list-objects-filter-options.h
+++ b/list-objects-filter-options.h
@@ -72,6 +72,26 @@ struct list_objects_filter_options {
 /* Normalized command line arguments */
 #define CL_ARG__FILTER "filter"
 
+/*
+ * Parse value of the argument to the "filter" keyword.
+ * On the command line this looks like:
+ *       --filter=<arg>
+ * and in the pack protocol as:
+ *       "filter" SP <arg>
+ *
+ * The filter keyword will be used by many commands.
+ * See Documentation/rev-list-options.txt for allowed values for <arg>.
+ *
+ * Capture the given arg as the "filter_spec".  This can be forwarded to
+ * subordinate commands when necessary (although it's better to pass it through
+ * expand_list_objects_filter_spec() first).  We also "intern" the arg for the
+ * convenience of the current command.
+ */
+int gently_parse_list_objects_filter(
+       struct list_objects_filter_options *filter_options,
+       const char *arg,
+       struct strbuf *errbuf);
+
 void list_objects_filter_die_if_populated(
        struct list_objects_filter_options *filter_options);