Re: [PATCH v2 07/12] bundle: safely handle --objects option
From: Ævar Arnfjörð Bjarmason <hidden>
Date: 2022-03-08 09:53:27
On Mon, Mar 07 2022, Derrick Stolee via GitGitGadget wrote:
quoted hunk ↗ jump to hunk
From: Derrick Stolee <redacted> Since 'git bundle' uses setup_revisions() to specify the object walk, some options do not make sense to include during the pack-objects child process. Further, these options are used for a call to traverse_commit_list() which would then require a callback which is currently NULL. By populating the callback we prevent a segfault in the case of adding the --objects flag. This is really a redundant statement because the command is constructing a pack-file containing all objects in the discovered commit range. Adding --objects to a 'git bundle' command might cause a slower command, but at least it will not have a hard failure when the user supplies this option. We can also disable walking trees and blobs in advance of this walk. Signed-off-by: Derrick Stolee <redacted> --- bundle.c | 10 +++++++++- t/t6020-bundle-misc.sh | 12 ++++++++++++ 2 files changed, 21 insertions(+), 1 deletion(-)diff --git a/bundle.c b/bundle.c index a0bb687b0f4..dc56db9a50a 100644 --- a/bundle.c +++ b/bundle.c@@ -451,6 +451,12 @@ struct bundle_prerequisites_info { int fd; }; + +static void ignore_object(struct object *obj, const char *v, void *data) +{ + /* Do nothing. */ +} + static void write_bundle_prerequisites(struct commit *commit, void *data) { struct bundle_prerequisites_info *bpi = data;@@ -544,7 +550,9 @@ int create_bundle(struct repository *r, const char *path, die("revision walk setup failed"); bpi.fd = bundle_fd; bpi.pending = &revs_copy.pending; - traverse_commit_list(&revs, write_bundle_prerequisites, NULL, &bpi); + + revs.blob_objects = revs.tree_objects = 0; + traverse_commit_list(&revs, write_bundle_prerequisites, ignore_object, &bpi); object_array_remove_duplicates(&revs_copy.pending); /* write bundle refs */diff --git a/t/t6020-bundle-misc.sh b/t/t6020-bundle-misc.sh index b13e8a52a93..6522401617d 100755 --- a/t/t6020-bundle-misc.sh +++ b/t/t6020-bundle-misc.sh@@ -475,4 +475,16 @@ test_expect_success 'clone from bundle' ' test_cmp expect actual ' +test_expect_success 'unfiltered bundle with --objects' ' + git bundle create all-objects.bdl \ + --all --objects && + git bundle create all.bdl \ + --all && + + # Compare the headers of these files. + head -11 all.bdl >expect && + head -11 all-objects.bdl >actual && + test_cmp expect actual +' + test_done
Re this comment on v1: https://lore.kernel.org/git/220307.86fsntzsda.gmgdl@evledraar.gmail.com/ (local) This series also passes your tests with this on top: diff --git a/bundle.c b/bundle.c index 3846108f7a6..1f022f53336 100644 --- a/bundle.c +++ b/bundle.c @@ -468,11 +468,6 @@ struct bundle_prerequisites_info { }; -static void ignore_object(struct object *obj, const char *v, void *data) -{ - /* Do nothing. */ -} - static void write_bundle_prerequisites(struct commit *commit, void *data) { struct bundle_prerequisites_info *bpi = data; @@ -598,7 +593,7 @@ int create_bundle(struct repository *r, const char *path, */ revs.filter = NULL; revs.blob_objects = revs.tree_objects = 0; - traverse_commit_list(&revs, write_bundle_prerequisites, ignore_object, &bpi); + traverse_commit_list(&revs, write_bundle_prerequisites, NULL, &bpi); object_array_remove_duplicates(&revs_copy.pending); /* write bundle refs */ diff --git a/list-objects.c b/list-objects.c index 9422625b39e..d44a1db2262 100644 --- a/list-objects.c +++ b/list-objects.c @@ -227,7 +227,7 @@ static void process_tag(struct traversal_context *ctx, ctx->filter); if (r & LOFR_MARK_SEEN) tag->object.flags |= SEEN; - if (r & LOFR_DO_SHOW) + if (r & LOFR_DO_SHOW && ctx->show_object) ctx->show_object(&tag->object, name, ctx->show_data); } Aside from whether that's a good idea, doesn't that at least point to missing test coverage here, see traverse_non_commits() and other paths in list-objects.c that'll call ctx->show_object(). I think an actually sensible patch for this is the below, i.e. the API is conflating "do show" with "should we show AND we have a callback?": diff --git a/bundle.c b/bundle.c index 3846108f7a6..1f022f53336 100644 --- a/bundle.c +++ b/bundle.c @@ -468,11 +468,6 @@ struct bundle_prerequisites_info { }; -static void ignore_object(struct object *obj, const char *v, void *data) -{ - /* Do nothing. */ -} - static void write_bundle_prerequisites(struct commit *commit, void *data) { struct bundle_prerequisites_info *bpi = data; @@ -598,7 +593,7 @@ int create_bundle(struct repository *r, const char *path, */ revs.filter = NULL; revs.blob_objects = revs.tree_objects = 0; - traverse_commit_list(&revs, write_bundle_prerequisites, ignore_object, &bpi); + traverse_commit_list(&revs, write_bundle_prerequisites, NULL, &bpi); object_array_remove_duplicates(&revs_copy.pending); /* write bundle refs */ diff --git a/list-objects.c b/list-objects.c index 9422625b39e..1725cb252a9 100644 --- a/list-objects.c +++ b/list-objects.c @@ -21,6 +21,22 @@ struct traversal_context { struct filter *filter; }; +static void show_commit(struct traversal_context *ctx, struct commit *commit, + void *data) +{ + if (!ctx->show_commit) + return; + ctx->show_commit(commit, data); +} + +static void show_object(struct traversal_context *ctx, struct object *object, + const char *path, void *data) +{ + if (!ctx->show_object) + return; + ctx->show_object(object, path, data); +} + static void process_blob(struct traversal_context *ctx, struct blob *blob, struct strbuf *path, @@ -60,7 +76,7 @@ static void process_blob(struct traversal_context *ctx, if (r & LOFR_MARK_SEEN) obj->flags |= SEEN; if (r & LOFR_DO_SHOW) - ctx->show_object(obj, path->buf, ctx->show_data); + show_object(ctx, obj, path->buf, ctx->show_data); strbuf_setlen(path, pathlen); } @@ -194,7 +210,7 @@ static void process_tree(struct traversal_context *ctx, if (r & LOFR_MARK_SEEN) obj->flags |= SEEN; if (r & LOFR_DO_SHOW) - ctx->show_object(obj, base->buf, ctx->show_data); + show_object(ctx, obj, base->buf, ctx->show_data); if (base->len) strbuf_addch(base, '/'); @@ -210,7 +226,7 @@ static void process_tree(struct traversal_context *ctx, if (r & LOFR_MARK_SEEN) obj->flags |= SEEN; if (r & LOFR_DO_SHOW) - ctx->show_object(obj, base->buf, ctx->show_data); + show_object(ctx, obj, base->buf, ctx->show_data); strbuf_setlen(base, baselen); free_tree_buffer(tree); @@ -228,7 +244,7 @@ static void process_tag(struct traversal_context *ctx, if (r & LOFR_MARK_SEEN) tag->object.flags |= SEEN; if (r & LOFR_DO_SHOW) - ctx->show_object(&tag->object, name, ctx->show_data); + show_object(ctx, &tag->object, name, ctx->show_data); } static void mark_edge_parents_uninteresting(struct commit *commit, @@ -402,7 +418,7 @@ static void do_traverse(struct traversal_context *ctx) if (r & LOFR_MARK_SEEN) commit->object.flags |= SEEN; if (r & LOFR_DO_SHOW) - ctx->show_commit(commit, ctx->show_data); + show_commit(ctx, commit, ctx->show_data); if (ctx->revs->tree_blobs_in_commit_order) /* I think that'll do what you want, and also seems to set us up for safer API use going forward, i.e. we have a couple of NULL-passing callers already.