Change commit.c to use ref transactions for all ref updates.
Make sure we pass a NULL pointer to ref_transaction_update if have_old
is false.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Update replace.c to use ref transactions for updates.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Change tag.c to use ref transactions for all ref updates.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Track the state of a transaction in a new state field. Check the field for
sanity, i.e. that state must be OPEN when _commit/_create/_delete or
_update is called or else die(BUG:...)
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Add an err argument to _begin so that on non-fatal failures in future ref
backends we can report a nice error back to the caller.
While _begin can currently never fail for other reasons than OOM, in which
case we die() anyway, we may add other types of backends in the future.
For example, a hypothetical MySQL backend could fail in _begin with
"Can not connect to MySQL server. No route to host".
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Change ref_transaction_delete() to do basic error checking and return
non-zero on error. Update all callers to check the return for
ref_transaction_delete(). There are currently no conditions in _delete that
will return error but there will be in the future. Add an err argument that
will be updated on failure.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Do basic error checking in ref_transaction_create() and make it return
non-zero on error. Update all callers to check the result of
ref_transaction_create(). There are currently no conditions in _create that
will return error but there will be in the future. Add an err argument that
will be updated on failure.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Reviewed-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Update ref_transaction_update() do some basic error checking and return
non-zero on error. Update all callers to check ref_transaction_update() for
error. There are currently no conditions in _update that will return error but
there will be in the future. Add an err argument that will be updated on
failure. In future patches we will start doing both locking and checking
for name conflicts in _update instead of _commit at which time this function
will start returning errors for these conditions.

Also check for BUGs during update and die(BUG:...) if we are calling
_update with have_old but the old_sha1 pointer is NULL.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Since all callers now use QUIET_ON_ERR we no longer need to provide an onerr
argument any more. Remove the onerr argument from the ref_transaction_commit
signature.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Call ref_transaction_commit with QUIET_ON_ERR and use the strbuf that is
returned to print a log message if/after the transaction fails.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Change update_ref_write to also update an error strbuf on failure.
This makes the error available to ref_transaction_commit callers if the
transaction failed due to update_ref_sha1/write_ref_sha1 failures.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Make ref_update_reject_duplicates return any error that occurs through a
new strbuf argument. This means that when a transaction commit fails in
this function we will now be able to pass a helpful error message back to the
caller.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno from write_ref_sha1() meaningful, which should fix

* a bug in "git checkout -b" where it prints strerror(errno)
  despite errno possibly being zero or clobbered

* a bug in "git fetch"'s s_update_ref, which trusts the result of an
  errno == ENOTDIR check to detect D/F conflicts
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno when returning from resolve_ref_unsafe() meaningful,
which should fix

 * a bug in lock_ref_sha1_basic, where it assumes EISDIR
   means it failed due to a directory being in the way
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno when returning from commit_packed_refs() meaningful,
which should fix

 * a bug in "git clone" where it prints strerror(errno) based on
   errno, despite errno possibly being zero and potentially having
   been clobbered by that point
 * the same kind of bug in "git pack-refs"

and prepares for repack_without_refs() to get a meaningful
error message when commit_packed_refs() fails without falling into
the same bug.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno when returning from remove_empty_directories() more
obviously meaningful, which should provide some peace of mind for
people auditing lock_ref_sha1_basic.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno when returning from verify_lock() meaningful, which
should almost but not completely fix

 * a bug in "git fetch"'s s_update_ref, which trusts the result of an
   errno == ENOTDIR check to detect D/F conflicts

ENOTDIR makes sense as a sign that a file was in the way of a
directory we wanted to create.  Should "git fetch" also look for
ENOTEMPTY or EEXIST to catch cases where a directory was in the way
of a file to be created?
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno when returning from log_ref_setup() meaningful,
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Update repack_without_refs to take an err argument and update it if there
is a failure. Pass the err variable from ref_transaction_commit to this
function so that callers can print a meaningful error message if _commit
fails due to this function.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Making errno when returning from lock_file() meaningful, which should
fix

 * an existing almost-bug in lock_ref_sha1_basic where it assumes
   errno==ENOENT is meaningful and could waste some work on retries

 * an existing bug in repack_without_refs where it prints
   strerror(errno) and picks advice based on errno, despite errno
   potentially being zero and potentially having been clobbered by
   that point
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Introducing a new unable_to_lock_message helper, which has nicer
semantics than unable_to_lock_error and cleans up lockfile.c a little.
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Add a strbuf argument to _commit so that we can pass an error string back to
the caller. So that we can do error logging from the caller instead of from
_commit.

Longer term plan is to first convert all callers to use onerr==QUIET_ON_ERR
and craft any log messages from the callers themselves and finally remove the
onerr argument completely.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Allow ref_transaction_free(NULL) as a no-op. This makes ref_transaction_free
easier to use and more similar to plain 'free'.

In particular, it lets us rollback unconditionally as part of cleanup code
after setting 'transaction = NULL' if a transaction has been committed or
rolled back already.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

ref_transaction_create|delete|update has no need to modify the sha1
arguments passed to it so it should use const unsigned char* instead
of unsigned char*.

Some functions, such as fast_forward_to(), already have its old/new
sha1 arguments as consts. This function will at some point need to
use ref_transaction_update() in which case this change is required.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

We do not yet need both a rollback and a free function for transactions.
Remove ref_transaction_rollback and use ref_transaction_free instead.

At a later stage we may reintroduce a rollback function if we want to start
adding reusable transactions and similar.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>
Acked-by: NMichael Haggerty <mhagger@alum.mit.edu>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Allow specifying only certain individual test pieces to be run
using a range notation (e.g. "t1234-test.sh --run='1-4 6 8 9-'").

* ib/test-selectively-run:
  t0000-*.sh: fix the GIT_SKIP_TESTS sub-tests
  test-lib: '--run' to run only specific tests
  test-lib: tests skipped by GIT_SKIP_TESTS say so
  test-lib: document short options in t/README

* ta/string-list-init:
  string-list: spell all values out that are given to a string_list initializer

* jm/dedup-test-config:
  t/t7810-grep.sh: remove duplicate test_config()

* dt/refs-check-refname-component-optim:
  refs.c: optimize check_refname_component()

* sk/test-cmp-bin:
  t5000, t5003: do not use test_cmp to compare binary files

* sh/enable-preloadindex:
  environment.c: enable core.preloadindex by default

* rs/read-ref-at:
  refs.c: change read_ref_at to use the reflog iterators

* jk/error-resolve-conflict-advice:
  error_resolve_conflict: drop quotations around operation
  error_resolve_conflict: rewrap advice message

Avoid unnecessary copy of previous contents when extending the
hashtable used in pack-objects.

* rs/pack-objects-no-unnecessary-realloc:
  pack-objects: use free()+xcalloc() instead of xrealloc()+memset()

* lt/log-auto-decorate:
  git log: support "auto" decorations

* jm/doc-wording-tweaks:
  Documentation: wording fixes in the user manual and glossary

* jm/format-patch-mail-sig:
  format-patch: add "--signature-file=<file>" option
  format-patch: make newline after signature conditional

Propagate the error messages from the webserver better to the
client coming over the HTTP transport.

* jk/http-errors:
  http: default text charset to iso-8859-1
  remote-curl: reencode http error messages
  strbuf: add strbuf_reencode helper
  http: optionally extract charset parameter from content-type
  http: extract type/subtype portion of content-type
  t5550: test display of remote http error messages
  t/lib-httpd: use write_script to copy CGI scripts
  test-lib: preserve GIT_CURL_VERBOSE from the environment