Commit Graph

173 Commits

Author SHA1 Message Date
Junio C Hamano
d2617eb984 Merge branch 'jt/fetch-pack-error-reporting'
"git fetch-pack" was not prepared to accept ERR packet that the
upload-pack can send with a human-readable error message.  It
showed the packet contents with ERR prefix, so there was no data
loss, but it was redundant to say "ERR" in an error message.

* jt/fetch-pack-error-reporting:
  fetch-pack: show clearer error message upon ERR
2017-04-23 22:07:53 -07:00
Jonathan Tan
8e2c7bef03 fetch-pack: show clearer error message upon ERR
Currently, fetch-pack prints a confusing error message ("expected
ACK/NAK") when the server it's communicating with sends a pkt-line
starting with "ERR".  Replace it with a less confusing error message.

Also update the documentation describing the fetch-pack/upload-pack
protocol (pack-protocol.txt) to indicate that "ERR" can be sent in the
place of "ACK" or "NAK". In practice, this has been done for quite some
time by other Git implementations (e.g. JGit sends "want $id not valid")
and by Git itself (since commit bdb31ea: "upload-pack: report "not our
ref" to client", 2017-02-23) whenever a "want" line references an object
that it does not have. (This is uncommon, but can happen if a repository
is garbage-collected during a negotiation.)

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-17 18:51:28 -07:00
brian m. carlson
910650d2f8 Rename sha1_array to oid_array
Since this structure handles an array of object IDs, rename it to struct
oid_array.  Also rename the accessor functions and the initialization
constant.

This commit was produced mechanically by providing non-Documentation
files to the following Perl one-liners:

    perl -pi -E 's/struct sha1_array/struct oid_array/g'
    perl -pi -E 's/\bsha1_array_/oid_array_/g'
    perl -pi -E 's/SHA1_ARRAY_INIT/OID_ARRAY_INIT/g'

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-31 08:33:56 -07:00
brian m. carlson
98a72ddc12 Make sha1_array_append take a struct object_id *
Convert the callers to pass struct object_id by changing the function
declaration and definition and applying the following semantic patch:

@@
expression E1, E2;
@@
- sha1_array_append(E1, E2.hash)
+ sha1_array_append(E1, &E2)

@@
expression E1, E2;
@@
- sha1_array_append(E1, E2->hash)
+ sha1_array_append(E1, E2)

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-31 08:33:55 -07:00
brian m. carlson
ee3051bd23 sha1-array: convert internal storage for struct sha1_array to object_id
Make the internal storage for struct sha1_array use an array of struct
object_id internally.  Update the users of this struct which inspect its
internals.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-28 09:59:34 -07:00
Junio C Hamano
07198afbd1 Merge branch 'mm/fetch-show-error-message-on-unadvertised-object'
"git fetch" that requests a commit by object name, when the other
side does not allow such an request, failed without much
explanation.

* mm/fetch-show-error-message-on-unadvertised-object:
  fetch-pack: add specific error for fetching an unadvertised object
  fetch_refs_via_pack: call report_unmatched_refs
  fetch-pack: move code to report unmatched refs to a function
2017-03-14 15:23:18 -07:00
Matt McCutchen
d56583ded6 fetch-pack: add specific error for fetching an unadvertised object
Enhance filter_refs (which decides whether a request for an unadvertised
object should be sent to the server) to record a new match status on the
"struct ref" when a request is not allowed, and have
report_unmatched_refs check for this status and print a special error
message, "Server does not allow request for unadvertised object".

Signed-off-by: Matt McCutchen <matt@mattmccutchen.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-02 11:12:53 -08:00
Matt McCutchen
e860d96bf8 fetch-pack: move code to report unmatched refs to a function
Prepare to reuse this code in transport.c for "git fetch".

While we're here, internationalize the existing error message.

Signed-off-by: Matt McCutchen <matt@mattmccutchen.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-02 11:12:53 -08:00
Jeff King
41a078c60b fetch-pack: cache results of for_each_alternate_ref
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 <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-08 15:39:55 -08:00
Jeff King
2429d63a46 for_each_alternate_ref: pass name/oid instead of ref struct
Breaking down the fields in the interface makes it easier to
change the backend of for_each_alternate_ref to something
that doesn't use "struct ref" internally.

The only field that callers actually look at is the oid,
anyway. The refname is kept in the interface as a plausible
thing for future code to want.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-08 15:39:55 -08:00
Ralf Thielow
dfbfb9f377 fetch-pack.c: correct command at the beginning of an error message
One error message in fetch-pack.c uses 'git fetch_pack' at the beginning
which is not a git command.  Use 'git fetch-pack' instead.

Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-11-11 13:28:39 -08:00
Junio C Hamano
a460ea4a3c Merge branch 'nd/shallow-deepen'
The existing "git fetch --depth=<n>" option was hard to use
correctly when making the history of an existing shallow clone
deeper.  A new option, "--deepen=<n>", has been added to make this
easier to use.  "git clone" also learned "--shallow-since=<date>"
and "--shallow-exclude=<tag>" options to make it easier to specify
"I am interested only in the recent N months worth of history" and
"Give me only the history since that version".

* nd/shallow-deepen: (27 commits)
  fetch, upload-pack: --deepen=N extends shallow boundary by N commits
  upload-pack: add get_reachable_list()
  upload-pack: split check_unreachable() in two, prep for get_reachable_list()
  t5500, t5539: tests for shallow depth excluding a ref
  clone: define shallow clone boundary with --shallow-exclude
  fetch: define shallow boundary with --shallow-exclude
  upload-pack: support define shallow boundary by excluding revisions
  refs: add expand_ref()
  t5500, t5539: tests for shallow depth since a specific date
  clone: define shallow clone boundary based on time with --shallow-since
  fetch: define shallow boundary with --shallow-since
  upload-pack: add deepen-since to cut shallow repos based on time
  shallow.c: implement a generic shallow boundary finder based on rev-list
  fetch-pack: use a separate flag for fetch in deepening mode
  fetch-pack.c: mark strings for translating
  fetch-pack: use a common function for verbose printing
  fetch-pack: use skip_prefix() instead of starts_with()
  upload-pack: move rev-list code out of check_non_tip()
  upload-pack: make check_non_tip() clean things up on error
  upload-pack: tighten number parsing at "deepen" lines
  ...
2016-10-10 14:03:50 -07:00
Junio C Hamano
b8688adb12 Merge branch 'rs/qsort'
We call "qsort(array, nelem, sizeof(array[0]), fn)", and most of
the time third parameter is redundant.  A new QSORT() macro lets us
omit it.

* rs/qsort:
  show-branch: use QSORT
  use QSORT, part 2
  coccicheck: use --all-includes by default
  remove unnecessary check before QSORT
  use QSORT
  add QSORT
2016-10-10 14:03:46 -07:00
René Scharfe
9ed0d8d6e6 use QSORT
Apply the semantic patch contrib/coccinelle/qsort.cocci to the code
base, replacing calls of qsort(3) with QSORT.  The resulting code is
shorter and supports empty arrays with NULL pointers.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-29 15:42:18 -07:00
Jonathan Tan
06b3d386e0 fetch-pack: do not reset in_vain on non-novel acks
The MAX_IN_VAIN mechanism was introduced in commit f061e5f ("fetch-pack:
give up after getting too many "ack continue"", 2006-05-24) to stop ref
negotiation if a number of consecutive "have"s have been sent with no
corresponding new acks. This is to stop the client from digging too deep
in an irrelevant side branch in vain without ever finding a common
ancestor. A use case (as described in that commit) is the scenario in
which the local repository has more roots than the remote repository.

However, during a negotiation in which stateless RPCs are used,
MAX_IN_VAIN will (almost) never trigger (in the more-roots scenario
above and others) because in each new request, the client has to inform
the server of objects it already has and knows the server has (to remind
the server of the state), which the server then acks.

Make fetch-pack only consider, as new acks for the purpose of
MAX_IN_VAIN, acks for objects for which the client has never received an
ack before in this session.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-23 12:37:45 -07:00
Jonathan Tan
da470981de fetch-pack: grow stateless RPC windows exponentially
When updating large repositories, the LARGE_FLUSH limit (that is, the
limit at which the window growth strategy switches from exponential to
linear) is reached quite quickly. Use a conservative exponential growth
strategy when that limit is reached instead (and increase LARGE_FLUSH so
that there is no regression in window size).

This optimization is only applied during stateless RPCs to avoid the
issue raised and fixed in commit 44d8dc54 (Fix potential local
deadlock during fetch-pack, 2011-03-29).

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-19 13:27:22 -07:00
Nguyễn Thái Ngọc Duy
cccf74e2da fetch, upload-pack: --deepen=N extends shallow boundary by N commits
In git-fetch, --depth argument is always relative with the latest
remote refs. This makes it a bit difficult to cover this use case,
where the user wants to make the shallow history, say 3 levels
deeper. It would work if remote refs have not moved yet, but nobody
can guarantee that, especially when that use case is performed a
couple months after the last clone or "git fetch --depth". Also,
modifying shallow boundary using --depth does not work well with
clones created by --since or --not.

This patch fixes that. A new argument --deepen=<N> will add <N> more (*)
parent commits to the current history regardless of where remote refs
are.

Have/Want negotiation is still respected. So if remote refs move, the
server will send two chunks: one between "have" and "want" and another
to extend shallow history. In theory, the client could send no "want"s
in order to get the second chunk only. But the protocol does not allow
that. Either you send no want lines, which means ls-remote; or you
have to send at least one want line that carries deep-relative to the
server..

The main work was done by Dongcan Jiang. I fixed it up here and there.
And of course all the bugs belong to me.

(*) We could even support --deepen=<N> where <N> is negative. In that
case we can cut some history from the shallow clone. This operation
(and --depth=<shorter depth>) does not require interaction with remote
side (and more complicated to implement as a result).

Helped-by: Duy Nguyen <pclouds@gmail.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Dongcan Jiang <dongcan.jiang@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
Nguyễn Thái Ngọc Duy
a45a260086 fetch: define shallow boundary with --shallow-exclude
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
Nguyễn Thái Ngọc Duy
508ea88226 fetch: define shallow boundary with --shallow-since
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
Nguyễn Thái Ngọc Duy
79891cb90a fetch-pack: use a separate flag for fetch in deepening mode
The shallow repo could be deepened or shortened when then user gives
--depth. But in future that won't be the only way to deepen/shorten a
repo. Stop relying on args->depth in this mode. Future deepening
methods can simply set this flag on instead of updating all these if
expressions.

The new name "deepen" was chosen after the command to define shallow
boundary in pack protocol. New commands also follow this tradition.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
Nguyễn Thái Ngọc Duy
1dd73e20d7 fetch-pack.c: mark strings for translating
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
Nguyễn Thái Ngọc Duy
0d789a5bc1 fetch-pack: use a common function for verbose printing
This reduces the number of "if (verbose)" which makes it a bit easier
to read imo. It also makes it easier to redirect all these printouts,
to a file for example.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
Jeff King
df85757244 fetch-pack: isolate sigpipe in demuxer thread
In commit 9ff18fa (fetch-pack: ignore SIGPIPE in sideband
demuxer, 2016-02-24), we started using sigchain_push() to
ignore SIGPIPE in the async demuxer thread. However, this is
rather clumsy, as it ignores SIGPIPE for the entire process,
including the main thread. At the time we didn't have any
per-thread signal support, but we now we do. Let's use it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-20 13:33:56 -07:00
Jeff King
9ff18faf2f fetch-pack: ignore SIGPIPE in sideband demuxer
If the other side feeds us a bogus pack, index-pack (or
unpack-objects) may die early, before consuming all of its
input. As a result, the sideband demuxer may get SIGPIPE
(racily, depending on whether our data made it into the pipe
buffer or not). If this happens and we are compiled with
pthread support, it will take down the main thread, too.

This isn't the end of the world, as the main process will
just die() anyway when it sees index-pack failed. But it
does mean we don't get a chance to say "fatal: index-pack
failed" or similar. And it also means that we racily fail
t5504, as we sometimes die() and sometimes are killed by
SIGPIPE.

So let's ignore SIGPIPE while demuxing the sideband. We are
already careful to check the return value of write(), so we
won't waste time writing to a broken pipe. The caller will
notice the error return from the async thread, though in
practice we don't even get that far, as we die() as soon as
we see that index-pack failed.

The non-sideband case is already fine; we let index-pack
read straight from the socket, so there is no SIGPIPE at
all. Technically the non-threaded async case is also OK
without this (the forked async process gets SIGPIPE), but
it's not worth distinguishing from the threaded case here.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 13:51:47 -08:00
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
brian m. carlson
f4e54d02b8 Convert struct ref to use object_id.
Use struct object_id in three fields in struct ref and convert all the
necessary places that use it.

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
Jeff King
984a43b902 fetch-pack: use argv_array for index-pack / unpack-objects
This cleans up a magic number that must be kept in sync with
the rest of the code (the number of argv slots). It also
lets us drop some fixed buffers and an sprintf (since we
can now use argv_array_pushf).

We do still have to keep one fixed buffer for calling
gethostname, but at least now the size computations for it
are much simpler.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:08:05 -07:00
Jeff King
f932729cc7 memoize common git-path "constant" files
One of the most common uses of git_path() is to pass a
constant, like git_path("MERGE_MSG"). This has two
drawbacks:

  1. The return value is a static buffer, and the lifetime
     is dependent on other calls to git_path, etc.

  2. There's no compile-time checking of the pathname. This
     is OK for a one-off (after all, we have to spell it
     correctly at least once), but many of these constant
     strings appear throughout the code.

This patch introduces a series of functions to "memoize"
these strings, which are essentially globals for the
lifetime of the program. We compute the value once, take
ownership of the buffer, and return the cached value for
subsequent calls.  cache.h provides a helper macro for
defining these functions as one-liners, and defines a few
common ones for global use.

Using a macro is a little bit gross, but it does nicely
document the purpose of the functions. If we need to touch
them all later (e.g., because we learned how to change the
git_dir variable at runtime, and need to invalidate all of
the stored values), it will be much easier to have the
complete list.

Note that the shared-global functions have separate, manual
declarations. We could do something clever with the macros
(e.g., expand it to a declaration in some places, and a
declaration _and_ a definition in path.c). But there aren't
that many, and it's probably better to stay away from
too-magical macros.

Likewise, if we abandon the C preprocessor in favor of
generating these with a script, we could get much fancier.
E.g., normalizing "FOO/BAR-BAZ" into "git_path_foo_bar_baz".
But the small amount of saved typing is probably not worth
the resulting confusion to readers who want to grep for the
function's definition.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:37:14 -07:00
Junio C Hamano
58eb0122f3 Merge branch 'me/fetch-into-shallow-safety'
"git fetch --depth=<depth>" and "git clone --depth=<depth>" issued
a shallow transfer request even to an upload-pack that does not
support the capability.

* me/fetch-into-shallow-safety:
  fetch-pack: check for shallow if depth given
2015-07-01 14:02:33 -07:00
Mike Edgar
eb86a507a1 fetch-pack: check for shallow if depth given
When a repository is first fetched as a shallow clone, either by
git-clone or by fetching into an empty repo, the server's capabilities
are not currently consulted. The client will send shallow requests even
if the server does not understand them, and the resulting error may be
unhelpful to the user. This change pre-emptively checks so we can exit
with a helpful error if necessary.

Signed-off-by: Mike Edgar <adgar@google.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-17 12:03:58 -07:00
Junio C Hamano
5455ee0573 Merge branch 'bc/object-id'
for_each_ref() callback functions were taught to name the objects
not with "unsigned char sha1[20]" but with "struct object_id".

* bc/object-id: (56 commits)
  struct ref_lock: convert old_sha1 member to object_id
  warn_if_dangling_symref(): convert local variable "junk" to object_id
  each_ref_fn_adapter(): remove adapter
  rev_list_insert_ref(): remove unneeded arguments
  rev_list_insert_ref_oid(): new function, taking an object_oid
  mark_complete(): remove unneeded arguments
  mark_complete_oid(): new function, taking an object_oid
  clear_marks(): rewrite to take an object_id argument
  mark_complete(): rewrite to take an object_id argument
  send_ref(): convert local variable "peeled" to object_id
  upload-pack: rewrite functions to take object_id arguments
  find_symref(): convert local variable "unused" to object_id
  find_symref(): rewrite to take an object_id argument
  write_one_ref(): rewrite to take an object_id argument
  write_refs_to_temp_dir(): convert local variable sha1 to object_id
  submodule: rewrite to take an object_id argument
  shallow: rewrite functions to take object_id arguments
  handle_one_ref(): rewrite to take an object_id argument
  add_info_ref(): rewrite to take an object_id argument
  handle_one_reflog(): rewrite to take an object_id argument
  ...
2015-06-05 12:17:37 -07:00
Michael Haggerty
c38cd1c89d rev_list_insert_ref(): remove unneeded arguments
Now that the function is not being used as an each_ref_sha1_fn, we can
delete the unused arguments in its signature.

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 12:19:39 -07:00
Michael Haggerty
b1b49c6eb6 rev_list_insert_ref_oid(): new function, taking an object_oid
This function can be used with for_each_ref() without having to be
wrapped.

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 12:19:39 -07:00
Michael Haggerty
6e20a51a80 mark_complete(): remove unneeded arguments
Now that the function is not being used as an each_ref_sha1_fn, we can
delete the unused arguments in its signature.

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 12:19:38 -07:00
Michael Haggerty
f8ee4d8522 mark_complete_oid(): new function, taking an object_oid
This function can be used with for_each_ref() without having to be
wrapped.

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 12:19:38 -07:00
Michael Haggerty
c50fb6cee6 clear_marks(): rewrite to take an object_id argument
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 12:19:38 -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
Fredrik Medley
68ee628932 upload-pack: optionally allow fetching reachable sha1
With uploadpack.allowReachableSHA1InWant configuration option set on the
server side, "git fetch" can make a request with a "want" line that names
an object that has not been advertised (likely to have been obtained out
of band or from a submodule pointer). Only objects reachable from the
branch tips, i.e. the union of advertised branches and branches hidden by
transfer.hideRefs, will be processed. Note that there is an associated
cost of having to walk back the history to check the reachability.

This feature can be used when obtaining the content of a certain commit,
for which the sha1 is known, without the need of cloning the whole
repository, especially if a shallow fetch is used. Useful cases are e.g.
repositories containing large files in the history, fetching only the
needed data for a submodule checkout, when sharing a sha1 without telling
which exact branch it belongs to and in Gerrit, if you think in terms of
commits instead of change numbers. (The Gerrit case has already been
solved through allowTipSHA1InWant as every Gerrit change has a ref.)

Signed-off-by: Fredrik Medley <fredrik.medley@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-22 18:25:36 -07:00
Fredrik Medley
7199c093ad upload-pack: prepare to extend allow-tip-sha1-in-want
To allow future extensions, e.g. allowing non-tip sha1, replace the
boolean allow_tip_sha1_in_want variable with the flag-style
allow_request_with_bare_object_name variable.

Signed-off-by: Fredrik Medley <fredrik.medley@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-22 18:25:35 -07:00
Jeff King
32d0462f8d fetch-pack: remove dead assignment to ref->new_sha1
In everything_local(), we used to assign the current ref's value
found in ref->old_sha1 to ref->new_sha1 when we already have all the
necessary objects to complete the history leading to that
commit.  This copying was broken at 49bb805e (Do not ask for
objects known to be complete., 2005-10-19) and ever since we
instead stuffed a random bytes in ref->new_sha1 here.  No
code complained or failed due to this breakage.

It turns out that no code path that comes after this
assignment even looks at ref->new_sha1 at all.

 - The only caller of everything_local(), do_fetch_pack(),
   returns this list of refs, whose element has bogus
   new_sha1 values, to its caller.  It does not look at the
   elements itself, but does pass them to find_common, which
   looks only at the name and old_sha1 fields.

 - The only caller of do_fetch_pack(), fetch_pack(), returns this
   list to its caller.  It does not look at the elements nor act on
   them.

 - One of the two callers of fetch_pack() is cmd_fetch_pack(), the
   top-level that implements "git fetch-pack".  The only thing it
   looks at in the elements of the returned ref list is the old_sha1
   and name fields.

 - The other caller of fetch_pack() is fetch_refs_via_pack() in the
   transport layer, which is a helper that implements "git fetch".
   It only cares about whether the returned list is empty (i.e.
   failed to fetch anything).

Just drop the bogus assignment, that is not even necessary.  The
remote-tracking refs are updated based on a different list and not
using the ref list being manipulated by this code path; the caller
do_fetch_pack() created a copy of that real ref list and passed the
copy down to this function, and modifying the elements here does not
affect anything.

Noticed-by: Kyle J. McKay <mackyle@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-19 14:11:52 -07:00
Jeff King
c3c17bf107 filter_ref: make a copy of extra "sought" entries
If the server supports allow_tip_sha1_in_want, we add any
unmatched raw-sha1 entries in our "sought" list of refs to
the list of refs we will ask the other side for. We do so by
inserting the original "struct ref" directly into our list,
rather than making a copy. This has several problems.

The most minor problem is that one cannot ever free the
resulting list; it contains structs that are copies of the
remote refs (made earlier by fetch_pack) along with sought
refs that are referenced elsewhere.

But more importantly that we set the ref->next pointer to
NULL, chopping off the remainder of any existing list that
the ref was a part of. We get the set of "sought" refs in
an array rather than a linked list, but that array is often
in turn generated from a list.  The test modification in
t5516 demonstrates this. Rather than fetching just an exact
sha1, we fetch that sha1 plus another ref:

  - we build a linked list of refs to fetch when do_fetch
    calls get_ref_map; the exact sha1 is first, followed by
    the named ref ("refs/heads/extra" in this case).

  - we pass that linked list to transport_fetch_ref, which
    squashes it into an array of pointers

  - that array goes to fetch_pack, which calls filter_ref.
    There we generate the want list from a mix of what the
    remote side has advertised, and the "sought" entry for
    the exact sha1. We set the sought entry's "next" pointer
    to NULL.

  - after we return from transport_fetch_refs, we then try
    to update the refs by following the linked list. But our
    list is now truncated, and we do not update
    refs/heads/extra at all.

We can fix this by making a copy of the ref. There's nothing
that fetch_pack does to it that must be reflected in the
original "sought" list (and indeed, if that were the case we
would have a serious bug, because it is only exact-sha1
entries which are treated this way).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-19 14:11:11 -07:00
Jeff King
b7916422c7 filter_ref: avoid overwriting ref->old_sha1 with garbage
If the server supports allow_tip_sha1_in_want, then
fetch-pack's filter_refs function tries to check whether a
ref is a request for a straight sha1 by running:

  if (get_sha1_hex(ref->name, ref->old_sha1))
	  ...

I.e., we are using get_sha1_hex to ask "is this ref name a
sha1?". If it is true, then the contents of ref->old_sha1
will end up unchanged. But if it is false, then get_sha1_hex
makes no guarantees about what it has written. With a ref
name like "abcdefoo", we would overwrite 3 bytes of
ref->old_sha1 before realizing that it was not a sha1.

This is likely not a problem in practice, as anything in
refs->name (besides a sha1) will start with "refs/", meaning
that we would notice on the first character that there is a
problem. Still, we are making assumptions about the state
left in the output when get_sha1_hex returns an error (e.g.,
it could start from the end of the string, or error check
the values only once they were placed in the output). It's
better to be defensive.

We could just check that we have exactly 40 characters of
sha1. But let's be even more careful and make sure that we
have a 40-char hex refname that matches what is in old_sha1.
This is perhaps overly defensive, but spells out our
assumptions clearly.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-19 13:52:54 -07:00
Michael Haggerty
697cc8efd9 lockfile.h: extract new header file for the functions in lockfile.c
Move the interface declaration for the functions in lockfile.c from
cache.h to a new file, lockfile.h. Add #includes where necessary (and
remove some redundant includes of cache.h by files that already
include builtin.h).

Move the documentation of the lock_file state diagram from lockfile.c
to the new header file.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:56:14 -07:00
Junio C Hamano
825fd93767 Merge branch 'rs/child-process-init'
Code clean-up.

* rs/child-process-init:
  run-command: inline prepare_run_command_v_opt()
  run-command: call run_command_v_opt_cd_env() instead of duplicating it
  run-command: introduce child_process_init()
  run-command: introduce CHILD_PROCESS_INIT
2014-09-11 10:33:27 -07:00
René Scharfe
d318027932 run-command: introduce CHILD_PROCESS_INIT
Most struct child_process variables are cleared using memset first after
declaration.  Provide a macro, CHILD_PROCESS_INIT, that can be used to
initialize them statically instead.  That's shorter, doesn't require a
function call and is slightly more readable (especially given that we
already have STRBUF_INIT, ARGV_ARRAY_INIT etc.).

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-20 09:53:37 -07:00
Tanay Abhra
f44af51d13 fetchpack.c: replace git_config() with git_config_get_*() family
Use `git_config_get_*()` family instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-07 13:33:27 -07:00
Junio C Hamano
e91ae32a01 Merge branch 'jk/skip-prefix'
* jk/skip-prefix:
  http-push: refactor parsing of remote object names
  imap-send: use skip_prefix instead of using magic numbers
  use skip_prefix to avoid repeated calculations
  git: avoid magic number with skip_prefix
  fetch-pack: refactor parsing in get_ack
  fast-import: refactor parsing of spaces
  stat_opt: check extra strlen call
  daemon: use skip_prefix to avoid magic numbers
  fast-import: use skip_prefix for parsing input
  use skip_prefix to avoid repeating strings
  use skip_prefix to avoid magic numbers
  transport-helper: avoid reading past end-of-string
  fast-import: fix read of uninitialized argv memory
  apply: use skip_prefix instead of raw addition
  refactor skip_prefix to return a boolean
  avoid using skip_prefix as a boolean
  daemon: mark some strings as const
  parse_diff_color_slot: drop ofs parameter
2014-07-09 11:33:28 -07:00
Jeff King
82e56767aa fetch-pack: refactor parsing in get_ack
There are several uses of the magic number "line+45" when
parsing ACK lines from the server, and it's rather unclear
why 45 is the correct number. We can make this more clear by
keeping a running pointer as we parse, using skip_prefix to
jump past the first "ACK ", then adding 40 to jump past
get_sha1_hex (which is still magical, but hopefully 40 is
less magical to readers of git code).

Note that this actually puts us at line+44. The original
required some character between the sha1 and further ACK
flags (it is supposed to be a space, but we never enforced
that). We start our search for flags at line+44, which
meanas we are slightly more liberal than the old code.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:45:19 -07:00