git/pack-objects.c, branch v2.18.2

Merge branch 'js/use-bug-macro'

2018-05-30T05:04:07Z

Developer support update, by using BUG() macro instead of die() to mark codepaths that should not happen more clearly. * js/use-bug-macro: BUG_exit_code: fix sparse "symbol not declared" warning Convert remaining die*(BUG) messages Replace all die("BUG: ...") calls by BUG() ones run-command: use BUG() to report bugs, not die() test-tool: help verifying BUG() code paths

Replace all die("BUG: ...") calls by BUG() ones

2018-05-06T10:06:13Z

In d8193743e08 (usage.c: add BUG() function, 2017-05-12), a new macro was introduced to use for reporting bugs instead of die(). It was then subsequently used to convert one single caller in 588a538ae55 (setup_git_env: convert die("BUG") to BUG(), 2017-05-12). The cover letter of the patch series containing this patch (cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not terribly clear why only one call site was converted, or what the plan is for other, similar calls to die() to report bugs. Let's just convert all remaining ones in one fell swoop. This trick was performed by this invocation: sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c) Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

pack-objects: shrink size field in struct object_entry

2018-04-16T03:38:59Z

It's very very rare that an uncompressed object is larger than 4GB (partly because Git does not handle those large files very well to begin with). Let's optimize it for the common case where object size is smaller than this limit. Shrink size field down to 31 bits and one overflow bit. If the size is too large, we read it back from disk. As noted in the previous patch, we need to return the delta size instead of canonical size when the to-be-reused object entry type is a delta instead of a canonical one. Add two compare helpers that can take advantage of the overflow bit (e.g. if the file is 4GB+, chances are it's already larger than core.bigFileThreshold and there's no point in comparing the actual value). Another note about oe_get_size_slow(). This function MUST be thread safe because SIZE() macro is used inside try_delta() which may run in parallel. Outside parallel code, no-contention locking should be dirt cheap (or insignificant compared to i/o access anyway). To exercise this code, it's best to run the test suite with something like make test GIT_TEST_OE_SIZE=4 which forces this code on all objects larger than 3 bytes. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano

pack-objects: move in_pack out of struct object_entry

2018-04-16T03:38:58Z

Instead of using 8 bytes (on 64 bit arch) to store a pointer to a pack. Use an index instead since the number of packs should be relatively small. This limits the number of packs we can handle to 1k. Since we can't be sure people can never run into the situation where they have more than 1k pack files. Provide a fall back route for it. If we find out they have too many packs, the new in_pack_by_idx[] array (which has at most 1k elements) will not be used. Instead we allocate in_pack[] array that holds nr_objects elements. This is similar to how the optional in_pack_pos field is handled. The new simple test is just to make sure the too-many-packs code path is at least executed. The true test is running make test GIT_TEST_FULL_IN_PACK_ARRAY=1 to take advantage of other special case tests. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano

pack: convert struct pack_idx_entry to struct object_id

2017-05-08T06:12:57Z

Convert struct pack_idx_entry to use struct object_id by changing the definition and applying the following semantic patch, plus the standard object_id transforms: @@ struct pack_idx_entry E1; @@ - E1.sha1 + E1.oid.hash @@ struct pack_idx_entry *E1; @@ - E1->sha1 + E1->oid.hash Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

use REALLOC_ARRAY for changing the allocation size of arrays

2014-09-18T16:13:42Z

Signed-off-by: Rene Scharfe Signed-off-by: Junio C Hamano

hashmap: factor out getting a hash code from a SHA1

2014-07-07T20:56:24Z

Copying the first bytes of a SHA1 is duplicated in six places, however, the implications (the actual value would depend on the endianness of the platform) is documented only once. Add a properly documented API for this. Signed-off-by: Karsten Blees Signed-off-by: Junio C Hamano

pack-objects: use free()+xcalloc() instead of xrealloc()+memset()

2014-06-02T20:51:22Z

Whenever the hash table becomes too small then its size is increased, the original part (and the added space) is zerod out using memset(), and the table is rebuilt from scratch. Simplify this proceess by returning the old memory using free() and allocating the new buffer using xcalloc(), which already clears the buffer for us. That way we avoid copying the old hash table contents needlessly inside xrealloc(). While at it, use the first array member with sizeof instead of a specific type. The old code used uint32_t and int, while index is actually an array of int32_t. Their sizes are the same basically everywhere, so it's not actually a problem, but the new code is cleaner and doesn't have to be touched should the type be changed. Signed-off-by: Rene Scharfe Signed-off-by: Junio C Hamano

pack-objects: refactor the packing list

2013-10-24T22:44:48Z

The hash table that stores the packing list for a given `pack-objects` run was tightly coupled to the pack-objects code. In this commit, we refactor the hash table and the underlying storage array into a `packing_data` struct. The functionality for accessing and adding entries to the packing list is hence accessible from other parts of Git besides the `pack-objects` builtin. This refactoring is a requirement for further patches in this series that will require accessing the commit packing list from outside of `pack-objects`. The hash table implementation has been minimally altered: we now use table sizes which are always a power of two, to ensure a uniform index distribution in the array. Signed-off-by: Vicent Marti Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Make git-pack-objects a builtin

2006-08-04T06:15:11Z

Signed-off-by: Matthias Kestenholz Signed-off-by: Junio C Hamano