From 3ae5fa0768f7f9781b40b1d40cb2f9f4c753bad4 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Thu, 7 Jun 2018 12:04:13 -0700 Subject: pack-bitmap: remove bitmap_git global variable Remove the bitmap_git global variable. Instead, generate on demand an instance of struct bitmap_index for code that needs to access it. This allows us significant control over the lifetime of instances of struct bitmap_index. In particular, packs can now be closed without worrying if an unnecessarily long-lived "pack" field in struct bitmap_index still points to it. The bitmap API is also clearer in that we need to first obtain a struct bitmap_index, then we use it. This patch raises two potential issues: (1) memory for the struct bitmap_index is allocated without being freed, and (2) prepare_bitmap_git() and prepare_bitmap_walk() can reuse a previously loaded bitmap. For (1), this will be dealt with in a subsequent patch in this patch set that also deals with freeing the contents of the struct bitmap_index (which were not freed previously, because they have global scope). For (2), current bitmap users only load the bitmap once at most (note that pack-objects can use bitmaps or write bitmaps, but not both at the same time), so support for reuse has no effect - and future users can pass around the struct bitmap_index * obtained if they need to do 2 or more things with the same bitmap. Helped-by: Stefan Beller Signed-off-by: Jonathan Tan Helped-by: Jeff King Signed-off-by: Junio C Hamano --- pack-bitmap-write.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'pack-bitmap-write.c') diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c index 7b2dc3e7dc..03e122563d 100644 --- a/pack-bitmap-write.c +++ b/pack-bitmap-write.c @@ -360,11 +360,13 @@ static int date_compare(const void *_a, const void *_b) void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack) { - if (prepare_bitmap_git() < 0) + struct bitmap_index *bitmap_git; + if (!(bitmap_git = prepare_bitmap_git())) return; writer.reused = kh_init_sha1(); - rebuild_existing_bitmaps(to_pack, writer.reused, writer.show_progress); + rebuild_existing_bitmaps(bitmap_git, to_pack, writer.reused, + writer.show_progress); } static struct ewah_bitmap *find_reused_bitmap(const unsigned char *sha1) -- cgit v1.2.3 From f3c23db2d7e764b247f7d76a8d0ba180811e9525 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Thu, 7 Jun 2018 12:04:14 -0700 Subject: pack-bitmap: add free function Add a function to free struct bitmap_index instances, and use it where needed (except when rebuild_existing_bitmaps() is used, since it creates references to the bitmaps within the struct bitmap_index passed to it). Note that the hashes field in struct bitmap_index is not freed because it points to another field within the same struct. The documentation for that field has been updated to clarify that. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano --- pack-bitmap-write.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'pack-bitmap-write.c') diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c index 03e122563d..7896fedd36 100644 --- a/pack-bitmap-write.c +++ b/pack-bitmap-write.c @@ -367,6 +367,10 @@ void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack) writer.reused = kh_init_sha1(); rebuild_existing_bitmaps(bitmap_git, to_pack, writer.reused, writer.show_progress); + /* + * NEEDSWORK: rebuild_existing_bitmaps() makes writer.reused reference + * some bitmaps in bitmap_git, so we can't free the latter. + */ } static struct ewah_bitmap *find_reused_bitmap(const unsigned char *sha1) -- cgit v1.2.3