"git am -3" calls "git merge-recursive" when it needs to fall back
to a three-way merge; this call has been turned into an internal
subroutine call instead of spawning a separate subprocess.
* js/am-3-merge-recursive-direct:
merge-recursive: flush output buffer even when erroring out
merge_trees(): ensure that the callers release output buffer
merge-recursive: offer an option to retain the output in 'obuf'
merge-recursive: write the commit title in one go
merge-recursive: flush output buffer before printing error messages
am -3: use merge_recursive() directly again
merge-recursive: switch to returning errors instead of dying
merge-recursive: handle return values indicating errors
merge-recursive: allow write_tree_from_memory() to error out
merge-recursive: avoid returning a wholesale struct
merge_recursive: abort properly upon errors
prepare the builtins for a libified merge_recursive()
merge-recursive: clarify code in was_tracked()
die(_("BUG")): avoid translating bug messages
die("bug"): report bugs consistently
t5520: verify that `pull --rebase` shows the helpful advice when failing
Call strbuf_addstr() for adding a simple string to a strbuf instead of
using the heavier strbuf_addf(). This is shorter and documents the
intent more clearly.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The recursive merge machinery accumulates its output in an output
buffer, to be flushed at the end of merge_recursive(). At this point,
we forgot to release the output buffer.
When calling merge_trees() (i.e. the non-recursive part of the recursive
merge) directly, the output buffer is never flushed because the caller
may be merge_recursive() which wants to flush the output itself.
For the same reason, merge_trees() cannot release the output buffer: it
may still be needed.
Forgetting to release the output buffer did not matter much when running
git-checkout, or git-merge-recursive, because we exited after the
operation anyway. Ever since cherry-pick learned to pick a commit range,
however, this memory leak had the potential of becoming a problem.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A helper function that takes the contents of a commit object and
finds its subject line did not ignore leading blank lines, as is
commonly done by other codepaths. Make it ignore leading blank
lines to match.
* js/find-commit-subject-ignore-leading-blanks:
reset --hard: skip blank lines when reporting the commit subject
sequencer: use skip_blank_lines() to find the commit subject
commit -C: skip blank lines at the beginning of the message
commit.c: make find_commit_subject() more robust
pretty: make the skip_blank_lines() function public
Previously, callers of merge_trees() or merge_recursive() expected that
code to die() with an error message. This used to be okay because we
called those commands from scripts, and had a chance to print out a
message in case the command failed fatally (read: with exit code 128).
As scripting incurs its own set of problems (portability, speed,
idiosyncrasies of different shells, limited data structures leading to
inefficient code), we are converting more and more of these scripts into
builtins, using library functions directly.
We already tried to use merge_recursive() directly in the builtin
git-am, for example. Unfortunately, we had to roll it back temporarily
because some of the code in merge-recursive.c still deemed it okay to
call die(), when the builtin am code really wanted to print out a useful
advice after the merge failed fatally. In the next commits, we want to
fix that.
The code touched by this commit expected merge_trees() to die() with
some useful message when there is an error condition, but merge_trees()
is going to be improved by converting all die() calls to return error()
instead (i.e. return value -1 after printing out the message as before),
so that the caller can react more flexibly.
This is a step to prepare for the version of merge_trees() that no
longer dies, even if we just imitate the previous behavior by calling
exit(128): this is what callers of e.g. `git merge` have come to expect.
Note that the callers of the sequencer (revert and cherry-pick) already
fail fast even for the return value -1; The only difference is that they
now get a chance to say "<command> failed".
A caller of merge_trees() might want handle error messages themselves
(or even suppress them). As this patch is already complex enough, we
leave that change for a later patch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More markings of messages for i18n, with updates to various tests
to pass GETTEXT_POISON tests.
One patch from the original submission dropped due to conflicts
with jk/upload-pack-hook, which is still in flux.
* va/i18n-even-more: (38 commits)
t5541: become resilient to GETTEXT_POISON
i18n: branch: mark comment when editing branch description for translation
i18n: unmark die messages for translation
i18n: submodule: escape shell variables inside eval_gettext
i18n: submodule: join strings marked for translation
i18n: init-db: join message pieces
i18n: remote: allow translations to reorder message
i18n: remote: mark URL fallback text for translation
i18n: standardise messages
i18n: sequencer: add period to error message
i18n: merge: change command option help to lowercase
i18n: merge: mark messages for translation
i18n: notes: mark options for translation
i18n: notes: mark strings for translation
i18n: transport-helper.c: change N_() call to _()
i18n: bisect: mark strings for translation
t5523: use test_i18ngrep for negation
t4153: fix negated test_i18ngrep call
t9003: become resilient to GETTEXT_POISON
tests: unpack-trees: update to use test_i18n* functions
...
A helper function that takes the contents of a commit object and
finds its subject line did not ignore leading blank lines, as is
commonly done by other codepaths. Make it ignore leading blank
lines to match.
* js/find-commit-subject-ignore-leading-blanks:
reset --hard: skip blank lines when reporting the commit subject
sequencer: use skip_blank_lines() to find the commit subject
commit -C: skip blank lines at the beginning of the message
commit.c: make find_commit_subject() more robust
pretty: make the skip_blank_lines() function public
"git cherry-pick A" worked on an unborn branch, but "git
cherry-pick A..B" didn't.
* mg/cherry-pick-multi-on-unborn:
cherry-pick: allow to pick to unborn branches
Just like we already taught the find_commit_subject() function (to make
it consistent with the code in pretty.c), we now simply skip leading
blank lines of the commit message.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git cherry-pick A" worked on an unborn branch, but "git
cherry-pick A..B" didn't.
* mg/cherry-pick-multi-on-unborn:
cherry-pick: allow to pick to unborn branches
Add a period to error message so it matches others instances in
sequencer.c. Now translator would have to translate such message only
once.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mark informative string "<action_name>: fast-forward" for translation.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mark entire sentences of error message rather than assembling one using
placeholders (e.g. "Cannot %s during a %s").
That would facilitate translation work because it is easier to translate
a entire sentence than translating pieces. We would have better
translations at the expense of source code verbosity.
Moreover, translators can now 1) translate the terms "revert" and
"cherry-pick" if they please 2) have more leeway to adapt their
translations.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
cherry-pick allows to pick single commits to an empty HEAD, but not
multiple commits.
Allow the multiple commit case, too.
Reported-by: Fabrizio Cucci <fabrizio.cucci@gmail.com>
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update various codepaths to avoid manually-counted malloc().
* jk/tighten-alloc: (22 commits)
ewah: convert to REALLOC_ARRAY, etc
convert ewah/bitmap code to use xmalloc
diff_populate_gitlink: use a strbuf
transport_anonymize_url: use xstrfmt
git-compat-util: drop mempcpy compat code
sequencer: simplify memory allocation of get_message
test-path-utils: fix normalize_path_copy output buffer size
fetch-pack: simplify add_sought_entry
fast-import: simplify allocation in start_packfile
write_untracked_extension: use FLEX_ALLOC helper
prepare_{git,shell}_cmd: use argv_array
use st_add and st_mult for allocation size computation
convert trivial cases to FLEX_ARRAY macros
use xmallocz to avoid size arithmetic
convert trivial cases to ALLOC_ARRAY
convert manual allocations to argv_array
argv-array: add detach function
add helpers for allocating flex-array structs
harden REALLOC_ARRAY and xcalloc against size_t overflow
tree-diff: catch integer overflow in combine_diff_path allocation
...
For a commit with sha1 "1234abcd" and subject "foo", this
function produces a struct with three strings:
1. "foo"
2. "1234abcd... foo"
3. "parent of 1234abcd... foo"
It takes advantage of the fact that these strings are
subsets of each other, and allocates only _one_ string, with
pointers into the various parts. Unfortunately, this makes
the string allocation complicated and hard to follow.
Since we keep only one of these in memory at a time, we can
afford to simply allocate three strings. This lets us build
on tools like xstrfmt and avoid manual computation.
While we're here, we can also drop the ad-hoc
reimplementation of get_git_commit_encoding(), and simply
call that function.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The strbuf_getline() interface allows a byte other than LF or NUL as
the line terminator, but this is only because I wrote these
codepaths anticipating that there might be a value other than NUL
and LF that could be useful when I introduced line_termination long
time ago. No useful caller that uses other value has emerged.
By now, it is clear that the interface is overly broad without a
good reason. Many codepaths have hardcoded preference to read
either LF terminated or NUL terminated records from their input, and
then call strbuf_getline() with LF or NUL as the third parameter.
This step introduces two thin wrappers around strbuf_getline(),
namely, strbuf_getline_lf() and strbuf_getline_nul(), and
mechanically rewrites these call sites to call either one of
them. The changes contained in this patch are:
* introduction of these two functions in strbuf.[ch]
* mechanical conversion of all callers to strbuf_getline() with
either '\n' or '\0' as the third parameter to instead call the
respective thin wrapper.
After this step, output from "git grep 'strbuf_getline('" would
become a lot smaller. An interim goal of this series is to make
this an empty set, so that we can have strbuf_getline_crlf() take
over the shorter name strbuf_getline().
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
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>
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>
To prepare for allowing a different "ref" backend to be plugged in
to the system, update_ref()/delete_ref() have been taught about
ref-like things like MERGE_HEAD that are per-worktree (they will
always be written to the filesystem inside $GIT_DIR).
* dt/refs-pseudo:
pseudoref: check return values from read_ref()
sequencer: replace write_cherry_pick_head with update_ref
bisect: use update_ref
pseudorefs: create and use pseudoref update and delete functions
refs: add ref_type function
refs: introduce pseudoref and per-worktree ref concepts
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>
Now update_ref (via write_pseudoref) does almost exactly what
write_cherry_pick_head did, so we can remove write_cherry_pick_head
and just use update_ref.
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git cherry-pick" used to clean-up the log message even when it is
merely replaying an existing commit. It now replays the message
verbatim unless you are editing the message of resulting commits.
* mg/sequencer-commit-messages-always-verbatim:
sequencer: preserve commit messages
sequencer calls "commit" with default options, which implies
"--cleanup=default" unless the user specified something else in their
config. This leads to cherry-picked commits getting a cleaned up commit
message, which is usually not an intended side-effect.
Make the sequencer use "--cleanup=verbatim" so that it preserves commit
messages independent of the default, unless the user has set config for "commit"
or the message is amended with -s or -x.
Reported-by: Christoph Anton Mitterer <calestyo@scientia.net>
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead, verify the reference's old value if and only if old_sha1 is
non-NULL.
ref_transaction_delete() will get the same treatment in a moment.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git interpret-trailers" learned to properly handle the
"Conflicts:" block at the end.
* cc/interpret-trailers-more:
trailer: add test with an old style conflict block
trailer: reuse ignore_non_trailer() to ignore conflict lines
commit: make ignore_non_trailer() non static
merge & sequencer: turn "Conflicts:" hint into a comment
builtin/commit.c: extract ignore_non_trailer() helper function
merge & sequencer: unify codepaths that write "Conflicts:" hint
builtin/merge.c: drop a parameter that is never used
* jc/conflict-hint:
merge & sequencer: turn "Conflicts:" hint into a comment
builtin/commit.c: extract ignore_non_trailer() helper function
merge & sequencer: unify codepaths that write "Conflicts:" hint
builtin/merge.c: drop a parameter that is never used
git-tag.txt: Add a missing hyphen to `-s`
Just like other hints such as "Changes to be committed" we show in
the editor to remind the committer what paths were involved in the
resulting commit to help improving their log message, this section
is merely a reminder.
Traditionally, it was not made into comments primarily because it
has to be generated outside the wt-status infrastructure, and also
because it was meant as a bit stronger reminder than the others
(i.e. explaining how you resolved conflicts is much more important
than mentioning what you did to every paths involved in the commit).
But that still does not make this hint a part of the log message
proper, and not showing it as a comment is inviting mistakes.
Note that we still notice "Conflicts:" followed by list of indented
pathnames as an old-style cruft and insert a new Signed-off-by:
before it. This is so that "commit --amend -s" adds the new S-o-b
at the right place when used on an older commit.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Two identical loops in suggest_conflicts() in merge, and
do_recursive_merge() in sequencer, can use a single helper function
extracted from the latter that prepares the "Conflicts:" hint that
is meant to remind the user the paths for which merge conflicts had
to be resolved to write a better commit log message.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
Change the ref transaction API so that we pass the reflog message to the
create/delete/update functions instead of to ref_transaction_commit.
This allows different reflog messages for each ref update in a multi-ref
transaction.
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>
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>
The second batch of the transactional ref update series.
* rs/ref-transaction-1: (22 commits)
update-ref --stdin: pass transaction around explicitly
update-ref --stdin: narrow scope of err strbuf
refs.c: make delete_ref use a transaction
refs.c: make prune_ref use a transaction to delete the ref
refs.c: remove lock_ref_sha1
refs.c: remove the update_ref_write function
refs.c: remove the update_ref_lock function
refs.c: make lock_ref_sha1 static
walker.c: use ref transaction for ref updates
fast-import.c: use a ref transaction when dumping tags
receive-pack.c: use a reference transaction for updating the refs
refs.c: change update_ref to use a transaction
branch.c: use ref transaction for all ref updates
fast-import.c: change update_branch to use ref transactions
sequencer.c: use ref transactions for all ref updates
commit.c: use ref transactions for updates
replace.c: use the ref transaction functions for updates
tag.c: use ref transactions when doing updates
refs.c: add transaction.status and track OPEN/CLOSED
refs.c: make ref_transaction_begin take an err argument
...
Change to use ref transactions for all updates to refs.
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An experiment to use two files (the base file and incremental
changes relative to it) to represent the index to reduce I/O cost
of rewriting a large index when only small part of the working tree
changes.
* nd/split-index: (32 commits)
t1700: new tests for split-index mode
t2104: make sure split index mode is off for the version test
read-cache: force split index mode with GIT_TEST_SPLIT_INDEX
read-tree: note about dropping split-index mode or index version
read-tree: force split-index mode off on --index-output
rev-parse: add --shared-index-path to get shared index path
update-index --split-index: do not split if $GIT_DIR is read only
update-index: new options to enable/disable split index mode
split-index: strip pathname of on-disk replaced entries
split-index: do not invalidate cache-tree at read time
split-index: the reading part
split-index: the writing part
read-cache: mark updated entries for split index
read-cache: save deleted entries in split index
read-cache: mark new entries for split index
read-cache: split-index mode
read-cache: save index SHA-1 after reading
entry.c: update cache_changed if refresh_cache is set in checkout_entry()
cache-tree: mark istate->cache_changed on prime_cache_tree()
cache-tree: mark istate->cache_changed on cache tree update
...
* jk/xstrfmt:
setup_git_env(): introduce git_path_from_env() helper
unique_path: fix unlikely heap overflow
walker_fetch: fix minor memory leak
merge: use argv_array when spawning merge strategy
sequencer: use argv_array_pushf
setup_git_env: use git_pathdup instead of xmalloc + sprintf
use xstrfmt to replace xmalloc + strcpy/strcat
use xstrfmt to replace xmalloc + sprintf
use xstrdup instead of xmalloc + strcpy
use xstrfmt in favor of manual size calculations
strbuf: add xstrfmt helper
Move "commit->buffer" out of the in-core commit object and keep
track of their lengths. Use this to optimize the code paths to
validate GPG signatures in commit objects.
* jk/commit-buffer-length:
reuse cached commit buffer when parsing signatures
commit: record buffer length in cache
commit: convert commit->buffer to a slab
commit-slab: provide a static initializer
use get_commit_buffer everywhere
convert logmsg_reencode to get_commit_buffer
use get_commit_buffer to avoid duplicate code
use get_cached_commit_buffer where appropriate
provide helpers to access the commit buffer
provide a helper to set the commit buffer
provide a helper to free commit buffer
sequencer: use logmsg_reencode in get_message
logmsg_reencode: return const buffer
do not create "struct commit" with xcalloc
commit: push commit_index update into alloc_commit_node
alloc: include any-object allocations in alloc_report
replace dangerous uses of strbuf_attach
commit_tree: take a pointer/len pair rather than a const strbuf
This avoids a manual allocation calculation, and is shorter
to boot.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Most callsites which use the commit buffer try to use the
cached version attached to the commit, rather than
re-reading from disk. Unfortunately, that interface provides
only a pointer to the NUL-terminated buffer, with no
indication of the original length.
For the most part, this doesn't matter. People do not put
NULs in their commit messages, and the log code is happy to
treat it all as a NUL-terminated string. However, some code
paths do care. For example, when checking signatures, we
want to be very careful that we verify all the bytes to
avoid malicious trickery.
This patch just adds an optional "size" out-pointer to
get_commit_buffer and friends. The existing callers all pass
NULL (there did not seem to be any obvious sites where we
could avoid an immediate strlen() call, though perhaps with
some further refactoring we could).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Each of these sites assumes that commit->buffer is valid.
Since they would segfault if this was not the case, they are
likely to be correct in practice. However, we can
future-proof them by using get_commit_buffer.
And as a side effect, we abstract away the final bare uses
of commit->buffer.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Like the callsites in the previous commit, logmsg_reencode
already falls back to read_sha1_file when necessary.
However, I split its conversion out into its own commit
because it's a bit more complex.
We return either:
1. The original commit->buffer
2. A newly allocated buffer from read_sha1_file
3. A reencoded buffer (based on either 1 or 2 above).
while trying to do as few extra reads/allocations as
possible. Callers currently free the result with
logmsg_free, but we can simplify this by pointing them
straight to unuse_commit_buffer. This is a slight layering
violation, in that we may be passing a buffer from (3).
However, since the end result is to free() anything except
(1), which is unlikely to change, and because this makes the
interface much simpler, it's a reasonable bending of the
rules.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This simplifies the code, as logmsg_reencode handles the
reencoding for us in a single call. It also means we learn
logmsg_reencode's trick of pulling the buffer from disk when
commit->buffer is NULL (we currently just silently return!).
It is doubtful this matters in practice, though, as
sequencer operations would not generally turn off
save_commit_buffer.
Note that we may be fixing a bug here. The existing code
does:
if (same_encoding(to, from))
reencode_string(buf, to, from);
That probably should have been "!same_encoding".
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`do_pick_commit` handles three situations if it is not fast-forwarding.
In order for `do_pick_commit` to identify the situation, it examines the
return value of the selected merge command.
1. return value 0 stands for a clean merge
2. 1 is passed in case of a failed merge due to conflict
3. any other return value means that the merge did not even start
So far, the sequencer returns 1 in case of a failed fast-forward, which
would mean "failed merge due to conflict". However, a fast-forward
either starts and succeeds or does not start at all. In particular, it
cannot fail in between like a merge with a dirty index due to conflicts.
In order to signal the three possible situations (not only success and
failure to complete) after a pick through porcelain commands such as
`cherry-pick`, exit with a return value that is neither 0 nor 1. 128 was
chosen in line with the other situations in which the sequencer
encounters an error. In such situations, the sequencer returns a
negative value and `cherry-pick` translates this into a call to `die`.
`die` then terminates the process with exit status 128.
Signed-off-by: Fabian Ruch <bafain@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>