From 5d3cd09a80819009636ae85c5171d9a4057eb372 Mon Sep 17 00:00:00 2001 From: Taylor Blau Date: Tue, 31 Aug 2021 16:52:02 -0400 Subject: midx: reject empty `--preferred-pack`'s The soon-to-be-implemented multi-pack bitmap treats object in the first bit position specially by assuming that all objects in the pack it was selected from are also represented from that pack in the MIDX. In other words, the pack from which the first object was selected must also have all of its other objects selected from that same pack in the MIDX in case of any duplicates. But this assumption relies on the fact that there is at least one object in that pack to begin with; otherwise the object in the first bit position isn't from a preferred pack, in which case we can no longer assume that all objects in that pack were also selected from the same pack. Guard this assumption by checking the number of objects in the given preferred pack, and failing if the given pack is empty. To make sure we can safely perform this check, open any packs which are contained in an existing MIDX via prepare_midx_pack(). The same is done for new packs via the add_pack_to_midx() callback, but packs picked up from a previous MIDX will not yet have these opened. Signed-off-by: Taylor Blau Signed-off-by: Junio C Hamano --- midx.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'midx.c') diff --git a/midx.c b/midx.c index 0bcb403bae..26089ec9c7 100644 --- a/midx.c +++ b/midx.c @@ -934,6 +934,25 @@ static int write_midx_internal(const char *object_dir, struct multi_pack_index * ctx.info[ctx.nr].pack_name = xstrdup(ctx.m->pack_names[i]); ctx.info[ctx.nr].p = NULL; ctx.info[ctx.nr].expired = 0; + + if (flags & MIDX_WRITE_REV_INDEX) { + /* + * If generating a reverse index, need to have + * packed_git's loaded to compare their + * mtimes and object count. + */ + if (prepare_midx_pack(the_repository, ctx.m, i)) { + error(_("could not load pack")); + result = 1; + goto cleanup; + } + + if (open_pack_index(ctx.m->packs[i])) + die(_("could not open index for %s"), + ctx.m->packs[i]->pack_name); + ctx.info[ctx.nr].p = ctx.m->packs[i]; + } + ctx.nr++; } } @@ -961,6 +980,16 @@ static int write_midx_internal(const char *object_dir, struct multi_pack_index * } } + if (ctx.preferred_pack_idx > -1) { + struct packed_git *preferred = ctx.info[ctx.preferred_pack_idx].p; + if (!preferred->num_objects) { + error(_("cannot select preferred pack %s with no objects"), + preferred->pack_name); + result = 1; + goto cleanup; + } + } + ctx.entries = get_sorted_entries(ctx.m, ctx.info, ctx.nr, &ctx.entries_nr, ctx.preferred_pack_idx); -- cgit v1.2.3