git/object.h, branch v2.14.2

object: remove "used" field from struct object

2017-07-20T21:54:08Z

The "used" field in struct object is only used by builtin/fsck. Remove that field and modify builtin/fsck to use a flag instead. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

object: convert parse_object* to take struct object_id

2017-05-08T06:12:58Z

Make parse_object, parse_object_or_die, and parse_object_buffer take a pointer to struct object_id. Remove the temporary variables inserted earlier, since they are no longer necessary. Transform all of the callers using the following semantic patch: @@ expression E1; @@ - parse_object(E1.hash) + parse_object(&E1) @@ expression E1; @@ - parse_object(E1->hash) + parse_object(E1) @@ expression E1, E2; @@ - parse_object_or_die(E1.hash, E2) + parse_object_or_die(&E1, E2) @@ expression E1, E2; @@ - parse_object_or_die(E1->hash, E2) + parse_object_or_die(E1, E2) @@ expression E1, E2, E3, E4, E5; @@ - parse_object_buffer(E1.hash, E2, E3, E4, E5) + parse_object_buffer(&E1, E2, E3, E4, E5) @@ expression E1, E2, E3, E4, E5; @@ - parse_object_buffer(E1->hash, E2, E3, E4, E5) + parse_object_buffer(E1, E2, E3, E4, E5) Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

fetch-pack: cache results of for_each_alternate_ref

2017-02-08T23:39:55Z

We may run for_each_alternate_ref() twice, once in find_common() and once in everything_local(). This operation can be expensive, because it involves running a sub-process which must freshly load all of the alternate's refs from disk. Let's cache and reuse the results between the two calls. We can make some optimizations based on the particular use pattern in fetch-pack to keep our memory usage down. The first is that we only care about the sha1s, not the refs themselves. So it's OK to store only the sha1s, and to suppress duplicates. The natural fit would therefore be a sha1_array. However, sha1_array's de-duplication happens only after it has read and sorted all entries. It still stores each duplicate. For an alternate with a large number of refs pointing to the same commits, this is a needless expense. Instead, we'd prefer to eliminate duplicates before putting them in the cache, which implies using a hash. We can further note that fetch-pack will call parse_object() on each alternate sha1. We can therefore keep our cache as a set of pointers to "struct object". That gives us a place to put our "already seen" bit with an optimized hash lookup. And as a bonus, the object stores the sha1 for us, so pointer-to-object is all we need. There are two extra optimizations I didn't do here: - we actually store an array of pointer-to-object. Technically we could just walk the obj_hash table looking for entries with the ALTERNATE flag set (because our use case doesn't care about the order here). But that hash table may be mostly composed of non-ALTERNATE entries, so we'd waste time walking over them. So it would be a slight win in memory use, but a loss in CPU. - the items we pull out of the cache are actual "struct object"s, but then we feed "obj->sha1" to our sub-functions, which promptly call parse_object(). This second parse is cheap, because it starts with lookup_object() and will bail immediately when it sees we've already parsed the object. We could save the extra hash lookup, but it would involve refactoring the functions we call. It may or may not be worth the trouble. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

upload-pack: add get_reachable_list()

2016-06-13T21:38:16Z

Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano

Remove get_object_hash.

2015-11-20T13:02:05Z

Convert all instances of get_object_hash to use an appropriate reference to the hash member of the oid member of struct object. This provides no functional change, as it is essentially a macro substitution. Signed-off-by: brian m. carlson Signed-off-by: Jeff King

Convert struct object to object_id

2015-11-20T13:02:05Z

struct object is one of the major data structures dealing with object IDs. Convert it to use struct object_id instead of an unsigned char array. Convert get_object_hash to refer to the new member as well. Signed-off-by: brian m. carlson Signed-off-by: Jeff King

object: introduce get_object_hash macro.

2015-11-20T13:02:05Z

This macro is a temporary change to ease the transition of struct object to use struct object_id. It takes an argument of struct object and returns the object's hash. Provide this hash next to struct object for easier conversion. Signed-off-by: brian m. carlson Signed-off-by: Jeff King

drop add_object_array_with_mode

2014-10-19T22:28:30Z

This is a thin compatibility wrapper around add_pending_object_with_path. But the only caller is add_object_array, which is itself just a thin compatibility wrapper. There are no external callers, so we can just remove this middle wrapper. Noticed-by: Ramsay Jones Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

make add_object_array_with_context interface more sane

2014-10-16T17:10:44Z

When you resolve a sha1, you can optionally keep any context found during the resolution, including the path and mode of a tree entry (e.g., when looking up "HEAD:subdir/file.c"). The add_object_array_with_context function lets you then attach that context to an entry in a list. Unfortunately, the interface for doing so is horrible. The object_context structure is large and most object_array users do not use it. Therefore we keep a pointer to the structure to avoid burdening other users too much. But that means when we do use it that we must allocate the struct ourselves. And the struct contains a fixed PATH_MAX-sized buffer, which makes this wholly unsuitable for any large arrays. We can observe that there is only a single user of the "with_context" variant: builtin/grep.c. And in that use case, the only element we care about is the path. We can therefore store only the path as a pointer (the context's mode field was redundant with the object_array_entry itself, and nobody actually cared about the surrounding tree). This still requires a strdup of the pathname, but at least we are only consuming the minimum amount of memory for each string. We can also handle the copying ourselves in add_object_array_*, and free it as appropriate in object_array_release_entry. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

object_array: add a "clear" function

2014-10-16T17:10:37Z

There's currently no easy way to free the memory associated with an object_array (and in most cases, we simply leak the memory in a rev_info's pending array). Let's provide a helper to make this easier to handle. We can make use of it in list-objects.c, which does the same thing by hand (but fails to free the "name" field of each entry, potentially leaking memory). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano