As with the previous two commits, UBSan with clang-11 complains about
computing offsets from a NULL pointer. The failures in t4013 (and
elsewhere) look like this:
kwset.c:102:23: runtime error: applying non-zero offset 107820859019600 to null pointer
...
not ok 79 - git log -SF master # magic is (not used)
That line is not enlightening:
... = obstack_alloc(&kwset->obstack, sizeof (struct trie));
because obstack is implemented almost entirely in macros, and the actual
problem is five macros deep (I temporarily converted them to inline
functions to get better compiler errors, which was tedious but worked
reasonably well).
The actual problem is in these pointer-alignment macros:
/* If B is the base of an object addressed by P, return the result of
aligning P to the next multiple of A + 1. B and P must be of type
char *. A + 1 must be a power of 2. */
#define __BPTR_ALIGN(B, P, A) ((B) + (((P) - (B) + (A)) & ~(A)))
/* Similar to _BPTR_ALIGN (B, P, A), except optimize the common case
where pointers can be converted to integers, aligned as integers,
and converted back again. If PTR_INT_TYPE is narrower than a
pointer (e.g., the AS/400), play it safe and compute the alignment
relative to B. Otherwise, use the faster strategy of computing the
alignment relative to 0. */
#define __PTR_ALIGN(B, P, A) \
__BPTR_ALIGN (sizeof (PTR_INT_TYPE) < sizeof (void *) ? (B) : (char *) 0, \
P, A)
If we have a sufficiently-large integer pointer type, then we do the
computation using a NULL pointer constant. That turns __BPTR_ALIGN()
into something like:
NULL + (P - NULL + A) & ~A
and UBSan is complaining about adding the full value of P to that
initial NULL. We can fix this by doing our math as an integer type, and
then casting the result back to a pointer. The problem case only happens
when we know that the integer type is large enough, so there should be
no issue with truncation.
Another option would be just simplify out all the 0's from
__BPTR_ALIGN() for the NULL-pointer case. That probably wouldn't work
for a platform where the NULL pointer isn't all-zeroes, but Git already
wouldn't work on such a platform (due to our use of memset to set
pointers in structs to NULL). But I tried here to keep as close to the
original as possible.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As with the previous commit, clang-11's UBSan complains about computing
offsets from a NULL pointer, causing some tests to fail. In this case,
though, we're actually computing a non-zero offset, which is even more
dubious. From t7810:
xdiff-interface.c:268:14: runtime error: applying non-zero offset 1 to null pointer
...
not ok 131 - grep -p with userdiff
The problem is our parsing of the funcname config. We count the number
of lines in the string, allocate an array, and then loop over our
allocated entries, parsing each line and moving our cursor to one past
the trailing newline for the next iteration.
But the final line will not generally have a trailing newline (since
it's a config value), and hence we go to one past NULL. In practice this
is OK, since our loop should terminate before we look at the value. But
even computing such an invalid pointer technically violates the
standard.
We can fix it by leaving the pointer at NULL if we're at the end, rather
than one-past. And while we're thinking about it, we can also document
the variant by asserting that our initial line-count matches the
second-pass of parsing.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The Undefined Behavior Sanitizer in clang-11 seems to have learned a new
trick: it complains about computing offsets from a NULL pointer, even if
that offset is 0. This causes numerous test failures. For example, from
t1090:
unpack-trees.c:1355:41: runtime error: applying zero offset to null pointer
...
not ok 6 - in partial clone, sparse checkout only fetches needed blobs
The code in question looks like this:
struct cache_entry **cache_end = cache + nr;
...
while (cache != cache_end)
and we sometimes pass in a NULL and 0 for "cache" and "nr". This is
conceptually fine, as "cache_end" would be equal to "cache" in this
case, and we wouldn't enter the loop at all. But computing even a zero
offset violates the C standard. And given the fact that UBSan is
noticing this behavior, this might be a potential problem spot if the
compiler starts making unexpected assumptions based on undefined
behavior.
So let's just avoid it, which is pretty easy. In some cases we can just
switch to iterating with a numeric index (as we do in sequencer.c here).
In other cases (like the cache_end one) the use of an end pointer is
more natural; we can keep that by just explicitly checking for the
NULL/0 case when assigning the end pointer.
Note that there are two ways you can write this latter case, checking
for the pointer:
cache_end = cache ? cache + nr : cache;
or the size:
cache_end = nr ? cache + nr : cache;
For the case of a NULL/0 ptr/len combo, they are equivalent. But writing
it the second way (as this patch does) has the property that if somebody
were to incorrectly pass a NULL pointer with a non-zero length, we'd
continue to notice and segfault, rather than silently pretending the
length was zero.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The flip_stage() helper uses a bit-flipping xor to switch between "2"
and "3". While clever, this relies on a property of those two numbers
that is mostly coincidence. Let's write it as a subtraction; that's more
clear and would extend to other numbers if somebody copies the logic.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The merge-recursive code uses stage number constants like this:
add = &ci->ren1->dst_entry->stages[2 ^ 1];
...
add = &ci->ren2->dst_entry->stages[3 ^ 1];
The xor has the effect of flipping the "1" bit, so that "2 ^ 1" becomes
"3" and "3 ^ 1" becomes "2", which correspond to the "ours" and "theirs"
stages respectively.
Unfortunately, clang-10 and up issue a warning for this code:
merge-recursive.c:1759:40: error: result of '2 ^ 1' is 3; did you mean '1 << 1' (2)? [-Werror,-Wxor-used-as-pow]
add = &ci->ren1->dst_entry->stages[2 ^ 1];
~~^~~
1 << 1
merge-recursive.c:1759:40: note: replace expression with '0x2 ^ 1' to silence this warning
We could silence it by using 0x2, as the compiler mentions. Or by just
using the constants "2" and "3" directly. But after digging into it, I
do think this bit-flip is telling us something. If we just wrote:
add = &ci->ren2->dst_entry->stages[2];
for the second one, you might think that "ren2" and "2" correspond. But
they don't. The logic is: ren2 is theirs, which is stage 3, but we
are interested in the opposite side's stage, so flip it to 2.
So let's keep the bit-flipping, but let's also put it behind a named
function, which will make its purpose a bit clearer. This also has the
side effect of suppressing the warning (and an optimizing compiler
should be able to easily turn it into a constant as before).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 49e268e23e (mingw: safeguard better against backslashes in file
names, 2020-01-09), the commit author is listed as
"Johannes Schindelin via GitGitGadget <gitgitgadget@gmail.com>", which
is erroneous. Fix the authorship by mapping the erroneous authorship to
his canonical authorship information.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With the upgrade, the library names changed from libeay32/ssleay32 to
libcrypto/libssl.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit 5d9324e0f4, reversing
changes made to c58ae96fc4.
The topic turns out to be too buggy for real use.
cf. <f2fe7437-8a48-3315-4d3f-8d51fe4bb8f1@gmail.com>
Further tweak to a "no backslash in indexed paths" for Windows port
we applied earlier.
* js/mingw-loosen-overstrict-tree-entry-checks:
mingw: safeguard better against backslashes in file names
In 224c7d70fa (mingw: only test index entries for backslashes, not tree
entries, 2019-12-31), we relaxed the check for backslashes in tree
entries to check only index entries.
However, the code change was incorrect: it was added to
`add_index_entry_with_check()`, not to `add_index_entry()`, so under
certain circumstances it was possible to side-step the protection.
Besides, the description of that commit purported that all index entries
would be checked when in fact they were only checked when being added to
the index (there are code paths that do not do that, constructing
"transient" index entries).
In any case, it was pointed out in one insightful review at
https://github.com/git-for-windows/git/pull/2437#issuecomment-566771835
that it would be a much better idea to teach `verify_path()` to perform
the check for a backslash. This is safer, even if it comes with two
notable drawbacks:
- `verify_path()` cannot say _what_ is wrong with the path, therefore
the user will no longer be told that there was a backslash in the
path, only that the path was invalid.
- The `git apply` command also calls the `verify_path()` function, and
might have been able to handle Windows-style paths (i.e. with
backslashes instead of forward slashes). This will no longer be
possible unless the user (temporarily) sets `core.protectNTFS=false`.
Note that `git add <windows-path>` will _still_ work because
`normalize_path_copy_len()` will convert the backslashes to forward
slashes before hitting the code path that creates an index entry.
The clear advantage is that `verify_path()`'s purpose is to check the
validity of the file name, therefore we naturally tap into all the code
paths that need safeguarding, also implicitly into future code paths.
The benefits of that approach outweigh the downsides, so let's move the
check from `add_index_entry_with_check()` to `verify_path()`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The english term generation is here not used in the sense of "to
generate" but in the sense of "generations of beings".
This corrects the initial translation from cf4c0c25 (l10n: update German
translation, 2018-12-06).
Fixed-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
The whole submoduleAlternateErrorStrategyDie item is interpreted as
being part of the supporting content of the preceding item. This is
because we don't give a double-colon "::" for the separator, but just a
single colon, ":". Let's fix that.
There are a few other matches for [^:]:\s*$ in Documentation/config, but
I didn't spot any similar bugs among them.
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since recent updates to the log graph rendering code, drawing
certain merges started triggering an assert on a condition that
would no longer hold true, which has been corrected.
* ds/graph-assert-fix:
graph: fix lack of color in horizontal lines
graph: drop assert() for merge with two collapsing parents
* https://github.com/prati0100/git-gui:
git-gui: allow opening currently selected file in default app
git-gui: allow closing console window with Escape
git gui: fix branch name encoding error
git-gui: revert untracked files by deleting them
git-gui: update status bar to track operations
git-gui: consolidate naming conventions
In some cases, horizontal lines in rendered graphs can lose their
coloring. This is due to a use of graph_line_addch() instead of
graph_line_write_column(). Using a ternary operator to pick the
character is nice for compact code, but we actually need a column to
provide the color.
Add a test to t4215-log-skewed-merges.sh to prevent regression.
Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When "git log --graph" shows a merge commit that has two collapsing
lines, like:
| | | | *
| |_|_|/|
|/| | |/
| | |/|
| |/| |
| * | |
* | | |
we trigger an assert():
graph.c:1228: graph_output_collapsing_line: Assertion
`graph->mapping[i - 3] == target' failed.
The assert was introduced by eaf158f8 ("graph API: Use horizontal
lines for more compact graphs", 2009-04-21), which is quite old.
This assert is trying to say that when we complete a horizontal
line with a single slash, it is because we have reached our target.
It is actually the _second_ collapsing line that hits this assert.
The reason we are in this code path is because we are collapsing
the first line, and in that case we are hitting our target now
that the horizontal line is complete. However, the second line
cannot be a horizontal line, so it will collapse without horizontal
lines. In this case, it is inappropriate to assert that we have
reached our target, as we need to continue for another column
before reaching the target. Dropping the assert is safe here.
The new behavior in 0f0f389f12 (graph: tidy up display of
left-skewed merges, 2019-10-15) caused the behavior change that
made this assertion failure possible. In addition to making the
assert possible, it also changed how multiple edges collapse.
In a larger example, the current code will output a collapse
as follows:
| | | | | | *
| |_|_|_|_|/|\
|/| | | | |/ /
| | | | |/| /
| | | |/| |/
| | |/| |/|
| |/| |/| |
| | |/| | |
| | * | | |
However, the intended collapse should allow multiple horizontal lines
as follows:
| | | | | | *
| |_|_|_|_|/|\
|/| | | | |/ /
| | |_|_|/| /
| |/| | | |/
| | | |_|/|
| | |/| | |
| | * | | |
This behavior is not corrected by this change, but is noted for a later
update.
Helped-by: Jeff King <peff@peff.net>
Reported-by: Bradley Smith <brad@brad-smith.co.uk>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to write split commit-graph file(s) upon fetching computed
bogus value for the parameter used in splitting the resulting
files, which has been corrected.
* ds/commit-graph-set-size-mult:
commit-graph: prefer default size_mult when given zero
"git sparse-checkout list" subcommand learned to give its output in
a more concise form when the "cone" mode is in effect.
* ds/sparse-list-in-cone-mode:
sparse-checkout: document interactions with submodules
sparse-checkout: list directories in cone mode
An earlier update to Git for Windows declared that a tree object is
invalid if it has a path component with backslash in it, which was
overly strict, which has been corrected. The only protection the
Windows users need is to prevent such path (or any path that their
filesystem cannot check out) from entering the index.
* js/mingw-loosen-overstrict-tree-entry-checks:
mingw: only test index entries for backslashes, not tree entries
The sentence wants to talk about the superproject's possesive, not plural form.
Signed-off-by: Thomas Menzel <dev@tomsit.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar to "From:" and "Subject:" already mentioned in the
documentation, "Date:" can also appear as an in-body header
to override the value in the e-mail headers. Document it.
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's core.multiPackIndex, not pack.multiIndex.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This typo was introduced in 94c0956b60 (sparse-checkout: create builtin
with 'list' subcommand, 2019-11-21).
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Allow opening the currently selected file in its default app by clicking
on its name.
* zs/open-current-file:
git-gui: allow opening currently selected file in default app
In 50f26bd ("fetch: add fetch.writeCommitGraph config setting",
2019-09-02), the fetch builtin added the capability to write a
commit-graph using the "--split" feature. This feature creates
multiple commit-graph files, and those can merge based on a set
of "split options" including a size multiple. The default size
multiple is 2, which intends to provide a log_2 N depth of the
commit-graph chain where N is the number of commits.
However, I noticed during dogfooding that my commit-graph chains
were becoming quite large when left only to builds by 'git fetch'.
It turns out that in split_graph_merge_strategy(), we default the
size_mult variable to 2 except we override it with the context's
split_opts if they exist. In builtin/fetch.c, we create such a
split_opts, but do not populate it with values.
This problem is due to two failures:
1. It is unclear that we can add the flag COMMIT_GRAPH_WRITE_SPLIT
with a NULL split_opts.
2. If we have a non-NULL split_opts, then we override the default
values even if a zero value is given.
Correct both of these issues. First, do not override size_mult when
the options provide a zero value. Second, stop creating a split_opts
in the fetch builtin.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
