Commit Graph

74 Commits

Author SHA1 Message Date
brian m. carlson
76c1d9a096 Convert object iteration callbacks to struct object_id
Convert each_loose_object_fn and each_packed_object_fn to take a pointer
to struct object_id.  Update the various callbacks.  Convert several
40-based constants to use GIT_SHA1_HEXSZ.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-22 10:12:15 -08:00
brian m. carlson
9461d27240 refs: convert each_reflog_ent_fn to struct object_id
Make each_reflog_ent_fn take two struct object_id pointers instead of
two pointers to unsigned char.  Convert the various callbacks to use
struct object_id as well.  Also, rename fsck_handle_reflog_sha1 to
fsck_handle_reflog_oid.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-22 10:12:15 -08:00
Junio C Hamano
4ba6197887 Merge branch 'jk/fsck-connectivity-check-fix'
"git fsck --connectivity-check" was not working at all.

* jk/fsck-connectivity-check-fix:
  fsck: lazily load types under --connectivity-only
  fsck: move typename() printing to its own function
  t1450: use "mv -f" within loose object directory
  fsck: check HAS_OBJ more consistently
  fsck: do not fallback "git fsck <bogus>" to "git fsck"
  fsck: tighten error-checks of "git fsck <head>"
  fsck: prepare dummy objects for --connectivity-check
  fsck: report trees as dangling
  t1450: clean up sub-objects in duplicate-entry test
2017-01-31 13:15:01 -08:00
Jeff King
a2b22854bd fsck: lazily load types under --connectivity-only
The recent fixes to "fsck --connectivity-only" load all of
the objects with their correct types. This keeps the
connectivity-only code path close to the regular one, but it
also introduces some unnecessary inefficiency. While getting
the type of an object is cheap compared to actually opening
and parsing the object (as the non-connectivity-only case
would do), it's still not free.

For reachable non-blob objects, we end up having to parse
them later anyway (to see what they point to), making our
type lookup here redundant.

For unreachable objects, we might never hit them at all in
the reachability traversal, making the lookup completely
wasted. And in some cases, we might have quite a few
unreachable objects (e.g., when alternates are used for
shared object storage between repositories, it's normal for
there to be objects reachable from other repositories but
not the one running fsck).

The comment in mark_object_for_connectivity() claims two
benefits to getting the type up front:

  1. We need to know the types during fsck_walk(). (And not
     explicitly mentioned, but we also need them when
     printing the types of broken or dangling commits).

     We can address this by lazy-loading the types as
     necessary. Most objects never need this lazy-load at
     all, because they fall into one of these categories:

       a. Reachable from our tips, and are coerced into the
	  correct type as we traverse (e.g., a parent link
	  will call lookup_commit(), which converts OBJ_NONE
	  to OBJ_COMMIT).

       b. Unreachable, but not at the tip of a chunk of
          unreachable history. We only mention the tips as
	  "dangling", so an unreachable commit which links
	  to hundreds of other objects needs only report the
	  type of the tip commit.

  2. It serves as a cross-check that the coercion in (1a) is
     correct (i.e., we'll complain about a parent link that
     points to a blob). But we get most of this for free
     already, because right after coercing, we'll parse any
     non-blob objects. So we'd notice then if we expected a
     commit and got a blob.

     The one exception is when we expect a blob, in which
     case we never actually read the object contents.

     So this is a slight weakening, but given that the whole
     point of --connectivity-only is to sacrifice some data
     integrity checks for speed, this seems like an
     acceptable tradeoff.

Here are before and after timings for an extreme case with
~5M reachable objects and another ~12M unreachable (it's the
torvalds/linux repository on GitHub, connected to shared
storage for all of the other kernel forks):

  [before]
  $ time git fsck --no-dangling --connectivity-only
  real	3m4.323s
  user	1m25.121s
  sys	1m38.710s

  [after]
  $ time git fsck --no-dangling --connectivity-only
  real	0m51.497s
  user	0m49.575s
  sys	0m1.776s

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-26 10:51:09 -08:00
Jeff King
97ca7ca8ba fsck: move typename() printing to its own function
When an object has a problem, we mention its type. But we do
so by feeding the result of typename() directly to
fprintf(). This is potentially dangerous because typename()
can return NULL for some type values (like OBJ_NONE).

It's doubtful that this can be triggered in practice with
the current code, so this is probably not fixing a bug. But
it future-proofs us against modifications that make things
like OBJ_NONE more likely (and gives future patches a
central point to handle them).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-26 10:47:20 -08:00
Jeff King
c2d17b3b6e fsck: check HAS_OBJ more consistently
There are two spots that call lookup_object() and assume
that a non-NULL result means we have the object:

  1. When we're checking the objects given to us by the user
     on the command line.

  2. When we're checking if a reflog entry is valid.

This generally follows fsck's mental model that we will have
looked at and loaded a "struct object" for each object in
the repository. But it misses one case: if another object
_mentioned_ an object, but we didn't actually parse it or
verify that it exists, it will still have a struct.

It's not clear if this is a triggerable bug or not.
Certainly the later parts of the reachability check need to
be careful of this, and do so by checking the HAS_OBJ flag.
But both of these steps happen before we start traversing,
so probably we won't have followed any links yet. Still,
it's easy enough to be defensive here.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-17 14:24:33 -08:00
Jeff King
c3271a0e47 fsck: do not fallback "git fsck <bogus>" to "git fsck"
Since fsck tries to continue as much as it can after seeing
an error, we still do the reachability check even if some
heads we were given on the command-line are bogus. But if
_none_ of the heads is is valid, we fallback to checking all
refs and the index, which is not what the user asked for at
all.

Instead of checking "heads", the number of successful heads
we got, check "argc" (which we know only has non-options in
it, because parse_options removed the others).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-17 14:24:33 -08:00
Jeff King
c6c7b16d23 fsck: tighten error-checks of "git fsck <head>"
Instead of checking reachability from the refs, you can ask
fsck to check from a particular set of heads. However, the
error checking here is quite lax. In particular:

  1. It claims lookup_object() will report an error, which
     is not true. It only does a hash lookup, and the user
     has no clue that their argument was skipped.

  2. When either the name or sha1 cannot be resolved, we
     continue to exit with a successful error code, even
     though we didn't check what the user asked us to.

This patch fixes both of these cases.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-17 14:24:33 -08:00
Jeff King
3e3f8bd608 fsck: prepare dummy objects for --connectivity-check
Normally fsck makes a pass over all objects to check their
integrity, and then follows up with a reachability check to
make sure we have all of the referenced objects (and to know
which ones are dangling). The latter checks for the HAS_OBJ
flag in obj->flags to see if we found the object in the
first pass.

Commit 02976bf85 (fsck: introduce `git fsck --connectivity-only`,
2015-06-22) taught fsck to skip the initial pass, and to
fallback to has_sha1_file() instead of the HAS_OBJ check.

However, it converted only one HAS_OBJ check to use
has_sha1_file(). But there are many other places in
builtin/fsck.c that assume that the flag is set (or that
lookup_object() will return an object at all). This leads to
several bugs with --connectivity-only:

  1. mark_object() will not queue objects for examination,
     so recursively following links from commits to trees,
     etc, did nothing. I.e., we were checking the
     reachability of hardly anything at all.

  2. When a set of heads is given on the command-line, we
     use lookup_object() to see if they exist. But without
     the initial pass, we assume nothing exists.

  3. When loading reflog entries, we do a similar
     lookup_object() check, and complain that the reflog is
     broken if the object doesn't exist in our hash.

So in short, --connectivity-only is broken pretty badly, and
will claim that your repository is fine when it's not.
Presumably nobody noticed for a few reasons.

One is that the embedded test does not actually test the
recursive nature of the reachability check. All of the
missing objects are still in the index, and we directly
check items from the index. This patch modifies the test to
delete the index, which shows off breakage (1).

Another is that --connectivity-only just skips the initial
pass for loose objects. So on a real repository, the packed
objects were still checked correctly. But on the flipside,
it means that "git fsck --connectivity-only" still checks
the sha1 of all of the packed objects, nullifying its
original purpose of being a faster git-fsck.

And of course the final problem is that the bug only shows
up when there _is_ corruption, which is rare. So anybody
running "git fsck --connectivity-only" proactively would
assume it was being thorough, when it was not.

One possibility for fixing this is to find all of the spots
that rely on HAS_OBJ and tweak them for the connectivity-only
case. But besides the risk that we might miss a spot (and I
found three already, corresponding to the three bugs above),
there are other parts of fsck that _can't_ work without a
full list of objects. E.g., the list of dangling objects.

Instead, let's make the connectivity-only case look more
like the normal case. Rather than skip the initial pass
completely, we'll do an abbreviated one that sets up the
HAS_OBJ flag for each object, without actually loading the
object data.

That's simple and fast, and we don't have to care about the
connectivity_only flag in the rest of the code at all.
While we're at it, let's make sure we treat loose and packed
objects the same (i.e., setting up dummy objects for both
and skipping the actual sha1 check). That makes the
connectivity-only check actually fast on a real repo (40
seconds versus 180 seconds on my copy of linux.git).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-17 14:23:20 -08:00
Jeff King
b4584e4f66 fsck: report trees as dangling
After checking connectivity, fsck looks through the list of
any objects we've seen mentioned, and reports unreachable
and un-"used" ones as dangling. However, it skips any object
which is not marked as "parsed", as that is an object that
we _don't_ have (but that somebody mentioned).

Since 6e454b9a3 (clear parsed flag when we free tree
buffers, 2013-06-05), that flag can't be relied on, and the
correct method is to check the HAS_OBJ flag. The cleanup in
that commit missed this callsite, though. As a result, we
would generally fail to report dangling trees.

We never noticed because there were no tests in this area
(for trees or otherwise). Let's add some.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-17 12:49:41 -08:00
Jeff King
c68b489e56 fsck: parse loose object paths directly
When we iterate over the list of loose objects to check, we
get the actual path of each object. But we then throw it
away and pass just the sha1 to fsck_sha1(), which will do a
fresh lookup. Usually it would find the same object, but it
may not if an object exists both as a loose and a packed
object. We may end up checking the packed object twice, and
never look at the loose one.

In practice this isn't too terrible, because if fsck doesn't
complain, it means you have at least one good copy. But
since the point of fsck is to look for corruption, we should
be thorough.

The new read_loose_object() interface can help us get the
data from disk, and then we replace parse_object() with
parse_object_buffer(). As a bonus, our error messages now
mention the path to a corrupted object, which should make it
easier to track down errors when they do happen.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-15 15:59:03 -08:00
Jeff King
597f9134de alternates: use a separate scratch space
The alternate_object_database struct uses a single buffer
both for storing the path to the alternate, and as a scratch
buffer for forming object names. This is efficient (since
otherwise we'd end up storing the path twice), but it makes
life hard for callers who just want to know the path to the
alternate. They have to remember to stop reading after
"alt->name - alt->base" bytes, and to subtract one for the
trailing '/'.

It would be much simpler if they could simply access a
NUL-terminated path string. We could encapsulate this in a
function which puts a NUL in the scratch buffer and returns
the string, but that opens up questions about the lifetime
of the result. The first time another caller uses the
alternate, the scratch buffer may get other data tacked onto
it.

Let's instead just store the root path separately from the
scratch buffer. There aren't enough alternates being stored
for the duplicated data to matter for performance, and this
keeps things simple and safe for the callers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-10 13:52:36 -07:00
brian m. carlson
7eda0e4fbb streaming: make stream_blob_to_fd take struct object_id
Since all of its callers have been updated, modify stream_blob_to_fd to
take a struct object_id.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-07 12:59:42 -07:00
brian m. carlson
99d1a9861a cache: convert struct cache_entry to use struct object_id
Convert struct cache_entry to use struct object_id by applying the
following semantic patch and the object_id transforms from contrib, plus
the actual change to the struct:

@@
struct cache_entry E1;
@@
- E1.sha1
+ E1.oid.hash

@@
struct cache_entry *E1;
@@
- E1->sha1
+ E1->oid.hash

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-07 12:59:42 -07:00
Junio C Hamano
ad2d777604 Merge branch 'nd/pack-ofs-4gb-limit'
"git pack-objects" and "git index-pack" mostly operate with off_t
when talking about the offset of objects in a packfile, but there
were a handful of places that used "unsigned long" to hold that
value, leading to an unintended truncation.

* nd/pack-ofs-4gb-limit:
  fsck: use streaming interface for large blobs in pack
  pack-objects: do not truncate result in-pack object size on 32-bit systems
  index-pack: correct "offset" type in unpack_entry_data()
  index-pack: report correct bad object offsets even if they are large
  index-pack: correct "len" type in unpack_data()
  sha1_file.c: use type off_t* for object_info->disk_sizep
  pack-objects: pass length to check_pack_crc() without truncation
2016-07-28 10:34:42 -07:00
Johannes Schindelin
90cf590f53 fsck: optionally show more helpful info for broken links
When reporting broken links between commits/trees/blobs, it would be
quite helpful at times if the user would be told how the object is
supposed to be reachable.

With the new --name-objects option, git-fsck will try to do exactly
that: name the objects in a way that shows how they are reachable.

For example, when some reflog got corrupted and a blob is missing that
should not be, the user might want to remove the corresponding reflog
entry. This option helps them find that entry: `git fsck` will now
report something like this:

	broken link from    tree b5eb6ff...  (refs/stash@{<date>}~37:)
	              to    blob ec5cf80...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-18 15:15:59 -07:00
Johannes Schindelin
1cd772cc41 fsck: give the error function a chance to see the fsck_options
We will need this in the next commit, where fsck will be taught to
optionally name the objects when reporting issues about them.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-18 11:35:00 -07:00
Johannes Schindelin
993a21b0a0 fsck: refactor how to describe objects
In many places, we refer to objects via their SHA-1s. Let's abstract
that into a function.

For the moment, it does nothing else than what we did previously: print
out the 40-digit hex string. But that will change over the course of the
next patches.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-18 11:35:00 -07:00
Nguyễn Thái Ngọc Duy
ec9d224903 fsck: use streaming interface for large blobs in pack
For blobs, we want to make sure the on-disk data is not corrupted
(i.e. can be inflated and produce the expected SHA-1). Blob content is
opaque, there's nothing else inside to check for.

For really large blobs, we may want to avoid unpacking the entire blob
in memory, just to check whether it produces the same SHA-1. On 32-bit
systems, we may not have enough virtual address space for such memory
allocation. And even on 64-bit where it's not a problem, allocating a
lot more memory could result in kicking other parts of systems to swap
file, generating lots of I/O and slowing everything down.

For this particular operation, not unpacking the blob and letting
check_sha1_signature, which supports streaming interface, do the job
is sufficient. check_sha1_signature() is not shown in the diff,
unfortunately. But if will be called when "data_valid && !data" is
false.

We will call the callback function "fn" with NULL as "data". The only
callback of this function is fsck_obj_buffer(), which does not touch
"data" at all if it's a blob.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-13 09:15:29 -07:00
Michael Haggerty
95ae2c7490 fsck_head_link(): remove unneeded flag variable
It is never read, so we can pass NULL to resolve_ref_unsafe().

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-10 11:35:33 -07:00
brian m. carlson
ed1c9977cb Remove get_object_hash.
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 <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 08:02:05 -05:00
brian m. carlson
f2fd0760f6 Convert struct object to object_id
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 <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 08:02:05 -05:00
brian m. carlson
7999b2cf77 Add several uses of get_object_hash.
Convert most instances where the sha1 member of struct object is
dereferenced to use get_object_hash.  Most instances that are passed to
functions that have versions taking struct object_id, such as
get_sha1_hex/get_oid_hex, or instances that can be trivially converted
to use struct object_id instead, are not converted.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 08:02:05 -05:00
Junio C Hamano
78891795df Merge branch 'jk/war-on-sprintf'
Many allocations that is manually counted (correctly) that are
followed by strcpy/sprintf have been replaced with a less error
prone constructs such as xstrfmt.

Macintosh-specific breakage was noticed and corrected in this
reroll.

* jk/war-on-sprintf: (70 commits)
  name-rev: use strip_suffix to avoid magic numbers
  use strbuf_complete to conditionally append slash
  fsck: use for_each_loose_file_in_objdir
  Makefile: drop D_INO_IN_DIRENT build knob
  fsck: drop inode-sorting code
  convert strncpy to memcpy
  notes: document length of fanout path with a constant
  color: add color_set helper for copying raw colors
  prefer memcpy to strcpy
  help: clean up kfmclient munging
  receive-pack: simplify keep_arg computation
  avoid sprintf and strcpy with flex arrays
  use alloc_ref rather than hand-allocating "struct ref"
  color: add overflow checks for parsing colors
  drop strcpy in favor of raw sha1_to_hex
  use sha1_to_hex_r() instead of strcpy
  daemon: use cld->env_array when re-spawning
  stat_tracking_info: convert to argv_array
  http-push: use an argv_array for setup_revisions
  fetch-pack: use argv_array for index-pack / unpack-objects
  ...
2015-10-20 15:24:01 -07:00
Junio C Hamano
30ce3b3bbc Merge branch 'jc/fsck-dropped-errors'
There were some classes of errors that "git fsck" diagnosed to its
standard error that did not cause it to exit with non-zero status.

* jc/fsck-dropped-errors:
  fsck: exit with non-zero when problems are found
2015-10-15 15:43:35 -07:00
Jeff King
f0766bf94e fsck: use for_each_loose_file_in_objdir
Since 27e1e22 (prune: factor out loose-object directory
traversal, 2014-10-15), we now have a generic callback
system for iterating over the loose object directories. This
is used by prune, count-objects, etc.

We did not convert git-fsck at the time because it
implemented an inode-sorting scheme that was not part of the
generic code. Now that the inode-sorting code is gone, we
can reuse the generic code.  The result is shorter,
hopefully more readable, and drops some unchecked sprintf
calls.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:08:06 -07:00
Jeff King
144e4cf709 fsck: drop inode-sorting code
Fsck tries to access loose objects in order of inode number,
with the hope that this would make cold cache access faster
on a spinning disk. This dates back to 7e8c174 (fsck-cache:
sort entries by inode number, 2005-05-02), which predates
the invention of packfiles.

These days, there's not much point in trying to optimize
cold cache for a large number of loose objects. You are much
better off to simply pack the objects, which will reduce the
disk footprint _and_ provide better locality of data access.

So while you can certainly construct pathological cases
where this code might help, it is not worth the trouble
anymore.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:08:06 -07:00
Jeff King
c1fd080917 fsck: use strbuf to generate alternate directories
When fsck-ing alternates, we make a copy of the alternate
directory in a fixed PATH_MAX buffer. We memcpy directly,
without any check whether we are overflowing the buffer.
This is OK if PATH_MAX is a true representation of the
maximum path on the system, because any path here will have
already been vetted by the alternates subsystem. But that is
not true on every system, so we should be more careful.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Jeff King
fbe85e73ce fsck: don't fsck alternates for connectivity-only check
Commit 02976bf (fsck: introduce `git fsck --connectivity-only`,
2015-06-22) recently gave fsck an option to perform only a
subset of the checks, by skipping the fsck_object_dir()
call. However, it does so only for the local object
directory, and we still do expensive checks on any alternate
repos. We should skip them in this case, too.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Junio C Hamano
122f76f574 fsck: exit with non-zero when problems are found
After finding some problems (e.g. a ref refs/heads/X points at an
object that is not a commit) and issuing an error message, the
program failed to signal the fact that it found an error by a
non-zero exit status.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-23 14:29:28 -07:00
Jeff King
fcd12db6af prefer git_pathdup to git_path in some possibly-dangerous cases
Because git_path uses a static buffer that is shared with
calls to git_path, mkpath, etc, it can be dangerous to
assign the result to a variable or pass it to a non-trivial
function. The value may change unexpectedly due to other
calls.

None of the cases changed here has a known bug, but they're
worth converting away from git_path because:

  1. It's easy to use git_pathdup in these cases.

  2. They use constructs (like assignment) that make it
     hard to tell whether they're safe or not.

The extra malloc overhead should be trivial, as an
allocation should be an order of magnitude cheaper than a
system call (which we are clearly about to make, since we
are constructing a filename). The real cost is that we must
remember to free the result.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:37:12 -07:00
Junio C Hamano
b2f44feba5 Merge branch 'js/fsck-opt'
Allow ignoring fsck errors on specific set of known-to-be-bad
objects, and also tweaking warning level of various kinds of non
critical breakages reported.

* js/fsck-opt:
  fsck: support ignoring objects in `git fsck` via fsck.skiplist
  fsck: git receive-pack: support excluding objects from fsck'ing
  fsck: introduce `git fsck --connectivity-only`
  fsck: support demoting errors to warnings
  fsck: document the new receive.fsck.<msg-id> options
  fsck: allow upgrading fsck warnings to errors
  fsck: optionally ignore specific fsck issues completely
  fsck: disallow demoting grave fsck errors to warnings
  fsck: add a simple test for receive.fsck.<msg-id>
  fsck: make fsck_tag() warn-friendly
  fsck: handle multiple authors in commits specially
  fsck: make fsck_commit() warn-friendly
  fsck: make fsck_ident() warn-friendly
  fsck: report the ID of the error/warning
  fsck (receive-pack): allow demoting errors to warnings
  fsck: offer a function to demote fsck errors to warnings
  fsck: provide a function to parse fsck message IDs
  fsck: introduce identifiers for fsck messages
  fsck: introduce fsck options
2015-08-03 11:01:18 -07:00
Junio C Hamano
8f61ccf15d Merge branch 'mh/fsck-reflog-entries'
"git fsck" used to ignore missing or invalid objects recorded in reflog.

* mh/fsck-reflog-entries:
  fsck: report errors if reflog entries point at invalid objects
  fsck_handle_reflog_sha1(): new function
2015-06-24 12:21:48 -07:00
Johannes Schindelin
1335f73289 fsck: support ignoring objects in git fsck via fsck.skiplist
Identical to support in `git receive-pack for the config option
`receive.fsck.skiplist`, we now support ignoring given objects in
`git fsck` via `fsck.skiplist` altogether.

This is extremely handy in case of legacy repositories where it would
cause more pain to change incorrect objects than to live with them
(e.g. a duplicate 'author' line in an early commit object).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:37 -07:00
Johannes Schindelin
02976bf856 fsck: introduce git fsck --connectivity-only
This option avoids unpacking each and all blob objects, and just
verifies the connectivity. In particular with large repositories, this
speeds up the operation, at the expense of missing corrupt blobs,
ignoring unreachable objects and other fsck issues, if any.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:37 -07:00
Johannes Schindelin
2becf00ff7 fsck: support demoting errors to warnings
We already have support in `git receive-pack` to deal with some legacy
repositories which have non-fatal issues.

Let's make `git fsck` itself useful with such repositories, too, by
allowing users to ignore known issues, or at least demote those issues
to mere warnings.

Example: `git -c fsck.missingEmail=ignore fsck` would hide
problems with missing emails in author, committer and tagger lines.

In the same spirit that `git receive-pack`'s usage of the fsck machinery
differs from `git fsck`'s – some of the non-fatal warnings in `git fsck`
are fatal with `git receive-pack` when receive.fsckObjects = true, for
example – we strictly separate the fsck.<msg-id> from the
receive.fsck.<msg-id> settings.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:36 -07:00
Johannes Schindelin
c99ba492f1 fsck: introduce identifiers for fsck messages
Instead of specifying whether a message by the fsck machinery constitutes
an error or a warning, let's specify an identifier relating to the
concrete problem that was encountered. This is necessary for upcoming
support to be able to demote certain errors to warnings.

In the process, simplify the requirements on the calling code: instead of
having to handle full-blown varargs in every callback, we now send a
string buffer ready to be used by the callback.

We could use a simple enum for the message IDs here, but we want to
guarantee that the enum values are associated with the appropriate
message types (i.e. error or warning?). Besides, we want to introduce a
parser in the next commit that maps the string representation to the
enum value, hence we use the slightly ugly preprocessor construct that
is extensible for use with said parser.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 10:24:27 -07:00
Johannes Schindelin
22410549fc fsck: introduce fsck options
Just like the diff machinery, we are about to introduce more settings,
therefore it makes sense to carry them around as a (pointer to a) struct
containing all of them.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 10:23:32 -07:00
Michael Haggerty
19bf6c9b34 fsck: report errors if reflog entries point at invalid objects
Previously, if a reflog entry's old or new SHA-1 was not resolvable to
an object, that SHA-1 was silently ignored. Instead, report such cases
as errors.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-08 12:40:36 -07:00
Michael Haggerty
d66ae59b8a fsck_handle_reflog_sha1(): new function
New function, extracted from fsck_handle_reflog_ent(). The extra
is_null_sha1() test for the new reference is currently unnecessary, as
reflogs are deleted when the reference itself is deleted. But it
doesn't hurt, either.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-08 12:37:32 -07:00
Michael Haggerty
635b99a0c7 fsck: change functions to use object_id
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-25 12:19:32 -07:00
Michael Haggerty
2b2a5be394 each_ref_fn: change to take an object_id parameter
Change typedef each_ref_fn to take a "const struct object_id *oid"
parameter instead of "const unsigned char *sha1".

To aid this transition, implement an adapter that can be used to wrap
old-style functions matching the old typedef, which is now called
"each_ref_sha1_fn"), and make such functions callable via the new
interface. This requires the old function and its cb_data to be
wrapped in a "struct each_ref_fn_sha1_adapter", and that object to be
used as the cb_data for an adapter function, each_ref_fn_adapter().

This is an enormous diff, but most of it consists of simple,
mechanical changes to the sites that call any of the "for_each_ref"
family of functions. Subsequent to this change, the call sites can be
rewritten one by one to use the new interface.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-25 12:19:27 -07:00
Junio C Hamano
68a2e6a2c8 Merge branch 'nd/multiple-work-trees'
A replacement for contrib/workdir/git-new-workdir that does not
rely on symbolic links and make sharing of objects and refs safer
by making the borrowee and borrowers aware of each other.

* nd/multiple-work-trees: (41 commits)
  prune --worktrees: fix expire vs worktree existence condition
  t1501: fix test with split index
  t2026: fix broken &&-chain
  t2026 needs procondition SANITY
  git-checkout.txt: a note about multiple checkout support for submodules
  checkout: add --ignore-other-wortrees
  checkout: pass whole struct to parse_branchname_arg instead of individual flags
  git-common-dir: make "modules/" per-working-directory directory
  checkout: do not fail if target is an empty directory
  t2025: add a test to make sure grafts is working from a linked checkout
  checkout: don't require a work tree when checking out into a new one
  git_path(): keep "info/sparse-checkout" per work-tree
  count-objects: report unused files in $GIT_DIR/worktrees/...
  gc: support prune --worktrees
  gc: factor out gc.pruneexpire parsing code
  gc: style change -- no SP before closing parenthesis
  checkout: clean up half-prepared directories in --to mode
  checkout: reject if the branch is already checked out elsewhere
  prune: strategies for linked checkouts
  checkout: support checking out into a new working directory
  ...
2015-05-11 14:23:39 -07:00
Alex Henrie
9c9b4f2f8b standardize usage info string format
This patch puts the usage info strings that were not already in docopt-
like format into docopt-like format, which will be a litle easier for
end users and a lot easier for translators. Changes include:

- Placing angle brackets around fill-in-the-blank parameters
- Putting dashes in multiword parameter names
- Adding spaces to [-f|--foobar] to make [-f | --foobar]
- Replacing <foobar>* with [<foobar>...]

Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-01-14 09:32:04 -08:00
Nguyễn Thái Ngọc Duy
dcf692625a path.c: make get_pathname() call sites return const char *
Before the previous commit, get_pathname returns an array of PATH_MAX
length. Even if git_path() and similar functions does not use the
whole array, git_path() caller can, in theory.

After the commit, get_pathname() may return a buffer that has just
enough room for the returned string and git_path() caller should never
write beyond that.

Make git_path(), mkpath() and git_path_submodule() return a const
buffer to make sure callers do not write in it at all.

This could have been part of the previous commit, but the "const"
conversion is too much distraction from the core changes in path.c.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:10 -08:00
Ronnie Sahlberg
7695d118e5 refs.c: change resolve_ref_unsafe reading argument to be a flags field
resolve_ref_unsafe takes a boolean argument for reading (a nonexistent ref
resolves successfully for writing but not for reading).  Change this to be
a flags field instead, and pass the new constant RESOLVE_REF_READING when
we want this behaviour.

While at it, swap two of the arguments in the function to put output
arguments at the end.  As a nice side effect, this ensures that we can
catch callers that were unaware of the new API so they can be audited.

Give the wrapper functions resolve_refdup and read_ref_full the same
treatment for consistency.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:24 -07:00
Junio C Hamano
13f4f04692 Merge branch 'js/fsck-tag-validation'
Teach "git fsck" to inspect the contents of annotated tag objects.

* js/fsck-tag-validation:
  Make sure that index-pack --strict checks tag objects
  Add regression tests for stricter tag fsck'ing
  fsck: check tag objects' headers
  Make sure fsck_commit_buffer() does not run out of the buffer
  fsck_object(): allow passing object data separately from the object itself
  Refactor type_from_string() to allow continuing after detecting an error
2014-09-26 14:39:43 -07:00
Junio C Hamano
5d62e59e4c Merge branch 'jk/fsck-exit-code-fix'
"git fsck" failed to report that it found corrupt objects via its
exit status in some cases.

* jk/fsck-exit-code-fix:
  fsck: return non-zero status on missing ref tips
  fsck: exit with non-zero status upon error from fsck_obj()
2014-09-19 11:38:42 -07:00
Jeff King
30d1038d1b fsck: return non-zero status on missing ref tips
Fsck tries hard to detect missing objects, and will complain
(and exit non-zero) about any inter-object links that are
missing. However, it will not exit non-zero for any missing
ref tips, meaning that a severely broken repository may
still pass "git fsck && echo ok".

The problem is that we use for_each_ref to iterate over the
ref tips, which hides broken tips. It does at least print an
error from the refs.c code, but fsck does not ever see the
ref and cannot note the problem in its exit code. We can solve
this by using for_each_rawref and noting the error ourselves.

In addition to adding tests for this case, we add tests for
all types of missing-object links (all of which worked, but
which we were not testing).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-12 10:45:49 -07:00
Johannes Schindelin
90a398bbd7 fsck_object(): allow passing object data separately from the object itself
When fsck'ing an incoming pack, we need to fsck objects that cannot be
read via read_sha1_file() because they are not local yet (and might even
be rejected if transfer.fsckobjects is set to 'true').

For commits, there is a hack in place: we basically cache commit
objects' buffers anyway, but the same is not true, say, for tag objects.

By refactoring fsck_object() to take the object buffer and size as
optional arguments -- optional, because we still fall back to the
previous method to look at the cached commit objects if the caller
passes NULL -- we prepare the machinery for the upcoming handling of tag
objects.

The assumption that such buffers are inherently NUL terminated is now
wrong, of course, hence we pass the size of the buffer so that we can
add a sanity check later, to prevent running past the end of the buffer.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-10 13:54:21 -07:00