Jeff King [Wed, 5 Jun 2024 08:35:26 +0000 (04:35 -0400)]
imap-send: free all_msgs strbuf in "out" label
We read stdin into a strbuf, but most code paths never release it,
causing a leak (albeit a minor one, as we leak only when exiting from
the main function of the program).
Commit 56f4f4a29d (imap-send: minimum leakfix, 2024-06-04) did the
minimum to plug the one instance we see in the test suite, when we read
an empty input. But it was sufficient only because aside from this noop
invocation, we don't test imap-send at all!
The right spot to free is in the "out" label, which is hit by all code
paths before leaving the function. We couldn't do that in 56f4f4a29d
because there was no unified exit path. That came separately in 3aca5f7fb0 (imap-send: fix leaking memory in `imap_server_conf`,
2024-06-04), which cleaned up many other leaks (but not this one).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Fri, 7 Jun 2024 17:32:02 +0000 (10:32 -0700)]
Merge branch 'ps/no-writable-strings' into jk/imap-send-plug-all-msgs-leak
* ps/no-writable-strings: (46 commits)
config.mak.dev: enable `-Wwrite-strings` warning
builtin/merge: always store allocated strings in `pull_twohead`
builtin/rebase: always store allocated string in `options.strategy`
builtin/rebase: do not assign default backend to non-constant field
imap-send: fix leaking memory in `imap_server_conf`
imap-send: drop global `imap_server_conf` variable
mailmap: always store allocated strings in mailmap blob
revision: always store allocated strings in output encoding
remote-curl: avoid assigning string constant to non-const variable
send-pack: always allocate receive status
parse-options: cast long name for OPTION_ALIAS
http: do not assign string constant to non-const field
compat/win32: fix const-correctness with string constants
pretty: add casts for decoration option pointers
object-file: make `buf` parameter of `index_mem()` a constant
object-file: mark cached object buffers as const
ident: add casts for fallback name and GECOS
entry: refactor how we remove items for delayed checkouts
line-log: always allocate the output prefix
line-log: stop assigning string constant to file parent buffer
...
Writing to string constants is undefined behaviour and must be avoided
in C. Even so, the compiler does not help us with this by default
because those constants are not in fact marked as `const`. This makes it
rather easy to accidentally assign a constant to a non-const variable or
field and then later on try to either free it or write to it.
Enable `-Wwrite-strings` to catch such mistakes. With this warning
enabled, the type of string constants is changed to `const char[]` and
will thus cause compiler warnings when being assigned to non-const
fields and variables.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/merge: always store allocated strings in `pull_twohead`
The `pull_twohead` configuration may sometimes contain an allocated
string, and sometimes it may contain a string constant. Refactor this to
instead always store an allocated string such that we can release its
resources without risk.
While at it, manage the lifetime of other config strings, as well. Note
that we explicitly don't free `cleanup_arg` here. This is because the
variable may be assigned a string constant via command line options.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/rebase: always store allocated string in `options.strategy`
The `struct rebase_options::strategy` field is a `char *`, but we do end
up assigning string constants to it in two cases:
- When being passed a `--strategy=` option via the command line.
- When being passed a strategy option via `--strategy-option=`, but
not a strategy.
This will cause warnings once we enable `-Wwrite-strings`.
Ideally, we'd just convert the field to be a `const char *`. But we also
assign to this field via the GIT_TEST_MERGE_ALGORITHM envvar, which we
have to strdup(3P) into it.
Instead, refactor the code to make sure that we only ever assign
allocated strings to this field.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/rebase: do not assign default backend to non-constant field
The `struct rebase_options::default_backend` field is a non-constant
string, but is being assigned a constant via `REBASE_OPTIONS_INIT`.
Fix this by using `xstrdup()` to assign the variable and introduce a new
function `rebase_options_release()` that releases memory held by the
structure, including the newly-allocated variable.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
imap-send: fix leaking memory in `imap_server_conf`
We never free any of the config strings that we populate into the
`struct imap_server_conf`. Fix this by creating a common exit path where
we can free resources.
While at it, drop the unused member `imap_server_conf::name`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
imap-send: drop global `imap_server_conf` variable
In "imap-send.c", we have a global `sturct imap_server_conf` variable
that keeps track of the configuration of the IMAP server. This variable
is being populated mostly via the Git configuration.
Refactor the code to allocate the structure on the stack instead of
having it globally. This change allows us to track its lifetime more
closely.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
mailmap: always store allocated strings in mailmap blob
Same as with the preceding commit, the `git_mailmap_blob` may sometimes
contain an allocated string and sometimes it may contain a string
constant. This is risky and can easily lead to bugs in case the variable
is getting re-assigned, where the code may then try to free the previous
value to avoid memory leaks.
Safeguard the code by always storing allocated strings in the variable.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
revision: always store allocated strings in output encoding
The `git_log_output_encoding` variable can be set via the `--encoding=`
option. When doing so, we conditionally either assign it to the passed
value, or if the value is "none" we assign it the empty string.
Depending on which of the both code paths we pick though, the variable
may end up being assigned either an allocated string or a string
constant.
This is somewhat risky and may easily lead to bugs when a different code
path may want to reassign a new value to it, freeing the previous value.
We already to this when parsing the "i18n.logoutputencoding" config in
`git_default_i18n_config()`. But because the config is typically parsed
before we parse command line options this has been fine so far.
Regardless of that, safeguard the code such that the variable always
contains an allocated string. While at it, also free the old value in
case there was any to plug a potential memory leak.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-curl: avoid assigning string constant to non-const variable
When processing remote options, we split the option line into two by
searching for a space. If there is one, we replace the space with '\0',
otherwise we implicitly assume that the value is "true" and thus assign
a string constant.
As the return value of strchr(3P) weirdly enough is a `char *` even
though it gets a `const char *` as input, the assigned-to variable also
is a non-constant. This is fine though because the argument is in fact
an allocated string, and thus we are allowed to modify it. But this will
break once we enable `-Wwrite-strings`.
Refactor the code stop splitting the fields with '\0' altogether.
Instead, we can pass the length of the option name to `set_option()` and
then use strncmp(3P) instead of strcmp(3P).
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In `receive_status()`, we record the reason why ref updates have been
rejected by the remote via the `remote_status`. But while we allocate
the assigned string when a reason was given, we assign a string constant
when no reason was given.
This has been working fine so far due to two reasons:
- We don't ever free the refs in git-send-pack(1)'
- Remotes always give a reason, at least as implemented by Git proper.
Adapt the code to always allocate the receive status string and free the
refs.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We assign the long name for OPTION_ALIAS options to a non-constant value
field. We know that the variable will never be written to, but this will
cause warnings once we enable `-Wwrite-strings`.
Cast away the constness to be prepared for this change.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
http: do not assign string constant to non-const field
In `write_accept_language()`, we put all acceptable languages into an
array. While all entries in that array are allocated strings, the final
entry in that array is a string constant. This is fine because we
explicitly skip over the last entry when freeing the array, but will
cause warnings once we enable `-Wwrite-strings`.
Adapt the code to also allocate the final entry.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `struct decoration_options` have a prefix and suffix field which are
both non-constant, but we assign a constant pointer to them. This is
safe to do because we pass them to `format_decorations()`, which never
modifies these pointers, and then immediately discard the structure. Add
explicit casts to avoid compilation warnings with `-Wwrite-strings`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file: make `buf` parameter of `index_mem()` a constant
The `buf` parameter of `index_mem()` is a non-constant string. This will
break once we enable `-Wwrite-strings` because we also pass constants
from at least one callsite.
Adapt the parameter to be a constant. As we cannot free the buffer
without casting now, this also requires us to move the lifetime of the
nested buffer around.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The buffers of cached objects are never modified, but are still stored
as a non-constant pointer. This will cause a compiler warning once we
enable the `-Wwrite-strings` compiler warning as we assign an empty
constant string when initializing the static `empty_tree` cached object.
Convert the field to be constant. This requires us to shuffle around
the code a bit because we memcpy(3P) into the allocated buffer in
`pretend_object_file()`. This is easily fixed though by allocating the
buffer into a temporary variable first.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In `xgetpwuid_self()`, we return a fallback identity when it was not
possible to look up the current identity. This fallback identity needs
to be internal and must never be written to by the calles as specified
by getpwuid(3P). As both the `pw_name` and `pw_gecos` fields are marked
as non-constant though, it will cause a warning to assign constant
strings to them once compiling with `-Wwrite-strings`.
Add explicit casts to avoid the warning.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
entry: refactor how we remove items for delayed checkouts
When finalizing a delayed checkout, we sort out several strings from the
passed-in string list by first assigning the empty string to those
filters and then calling `string_list_remove_empty_items()`. Assigning
the empty string will cause compiler warnings though as the string is
a `char *` once we enable `-Wwrite-strings`.
Refactor the code to use a `NULL` pointer with `filter_string_list()`
instead to avoid this warning.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The returned string by `output_prefix()` is sometimes a string constant
and sometimes an allocated string. This has been fine until now because
we always leak the allocated strings, and thus we never tried to free
the string constant.
Fix the code to always return an allocated string and free the returned
value at all callsites.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
line-log: stop assigning string constant to file parent buffer
Stop assigning a string constant to the file parent buffer and instead
assign an allocated string. While the code is fine in practice, it will
break once we compile with `-Wwrite-strings`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `fill_textconv()` function is responsible for converting an input
file with a textconv driver, which is then passed to the caller. Weirdly
though, the function also handles the case where there is no textconv
driver at all. In that case, it will return either the contents of the
populated filespec, or an empty string if the filespec is invalid.
These two cases have differing memory ownership semantics. When there is
a textconv driver, then the result is an allocated string. Otherwise,
the result is either a string constant or owned by the filespec struct.
All callers are in fact aware of this weirdness and only end up freeing
the output buffer when they had a textconv driver.
Ideally, we'd split up this interface to only perform the conversion via
the textconv driver, and BUG in case the caller didn't provide one. This
would make memory ownership semantics much more straight forward. For
now though, let's simply cast the empty string constant to `char *` to
avoid a warning with `-Wwrite-strings`. This is equivalent to the same
cast that we already have in `fill_mmfile()`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/remote: cast away constness in `get_head_names()`
In `get_head_names()`, we assign the "refs/heads/*" string constant to
`struct refspec_item::{src,dst}`, which are both non-constant pointers.
Ideally, we'd refactor the code such that both of these fields were
constant. But `struct refspec_item` is used for two different usecases
with conflicting requirements:
- To query for a source or destination based on the given refspec. The
caller either sets `src` or `dst` as the branch that we want to
search for, and the respective other field gets populated. The
fields should be constant when being used as a query parameter,
which is owned by the caller, and non-constant when being used as an
out parameter, which is owned by the refspec item. This is is
contradictory in itself already.
- To store refspec items with their respective source and destination
branches, in which case both fields should be owned by the struct.
Ideally, we'd split up this interface to clearly separate between
querying and storing, which would enable us to clarify lifetimes of the
strings. This would be a much bigger undertaking though.
Instead, accept the status quo for now and cast away the constness of
the source and destination patterns. We know that those are not being
written to or freed, so while this is ugly it certainly is fine for now.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have a global tag refspec structure that is used by both git-clone(1)
and git-fetch(1). Initialization of the structure will break once we
enable `-Wwrite-strings`, even though the breakage is harmless. While we
could just add casts, the structure isn't really required in the first
place as we can simply initialize the structures at the respective
callsites.
Refactor the code accordingly.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
reftable: cast away constness when assigning constants to records
The reftable records are used in multiple ways throughout the reftable
library. In many of those cases they merely act as input to a function
without getting modified by it at all. Most importantly, this happens
when writing records and when querying for records.
We rely on this in our tests and thus assign string constants to those
fields, which is about to generate warnings as those fields are of type
`char *`. While we could go through the process and instead allocate
those strings in all of our tests, this feels quite unnecessary.
Instead, add casts to `char *` for all of those strings. As this is part
of our tests, this also nicely serves as a demonstration that nothing
writes or frees those string constants, which would otherwise lead to
segfaults.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/reftable: stop micro-optimizing refname allocations on copy
When copying refs, we execute `write_copy_table()` to write the new
table. As the names are given to us via `arg->newname` and
`arg->oldname`, respectively, we optimize away some allocations by
assigning those fields to the reftable records we are about to write
directly, without duplicating them. This requires us to cast the input
to `char *` pointers as they are in fact constant strings. Later on, we
then unset the refname for all of the records before calling
`reftable_log_record_release()` on them.
We also do this when assigning the "HEAD" constant, but here we do not
cast because its type is `char[]` by default. It's about to be turned
into `const char *` though once we enable `-Wwrite-strings` and will
thus cause another warning.
It's quite dubious whether this micro-optimization really helps. We're
about to write to disk anyway, which is going to be way slower than a
small handful of allocations. Let's drop the optimization altogther and
instead copy arguments to simplify the code and avoid the future warning
with `-Wwrite-strings`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
global: convert intentionally-leaking config strings to consts
There are multiple cases where we intentionally leak config strings:
- `struct gpg_format` is used to track programs that can be used for
signing commits, either via gpg(1), gpgsm(1) or ssh-keygen(1). The
user can override the commands via several config variables. As the
array is populated once, only, and the struct memers are never
written to or free'd.
- `struct ll_merge_driver` is used to track merge drivers. Same as
with the GPG format, these drivers are populated once and then
reused. Its data is never written to or free'd, either.
- `struct userdiff_funcname` and `struct userdiff_driver` can be
configured via `diff.<driver>.*` to add additional drivers. Again,
these have a global lifetime and are never written to or free'd.
All of these are intentionally kept alive and are never written to.
Furthermore, all of these are being assigned both string constants in
some places, and allocated strings in other places. This will cause
warnings once we enable `-Wwrite-strings`, so let's mark the respective
fields as `const char *` and cast away the constness when assigning
those values.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
global: improve const correctness when assigning string constants
We're about to enable `-Wwrite-strings`, which changes the type of
string constants to `const char[]`. Fix various sites where we assign
such constants to non-const variables.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Tue, 4 Jun 2024 18:46:10 +0000 (11:46 -0700)]
imap-send: minimum leakfix
EVen with the minimum "no-op" invocation t1517 makes, "git imap-send"
leaks an empty strbuf it used to read a 0-byte string into.
There are a few other topics cooking in 'next' that plugs many
other leaks in this program, so let's minimally fix this one, barely
enough to make CI pass, leaving the rest for the other topic.
Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Fri, 31 May 2024 08:43:27 +0000 (01:43 -0700)]
t1517: more coverage for commands that work without repository
While most of the commands in Git suite are designed to do useful
things in Git repositories, some commands are also usable outside
any repository. Building on top of an earlier work abece6e9 (t1517:
test commands that are designed to be run outside repository,
2024-05-20) that adds tests for such commands, let's give coverage
to some more commands.
This patch covers commands whose code has hits for
$ git grep setup_git_directory_gently
and passes a pointer to nongit_ok variable it uses to allow it to
run outside a Git repository, but mostly they are tested only to see
that they start up (as opposed to dying with "not in a git
repository" complaint). We may want to update them to actually do
something useful later, but this would at least help us catch
regressions by mistake.
The base topic started to make it an error for a command to leave
the hash algorithm unspecified, which revealed a few commands that
were not ready for the change. Give users a knob to revert back to
the "default is sha-1" behaviour as an escape hatch, and start
fixing these breakages.
* jc/undecided-is-not-necessarily-sha1-fix:
apply: fix uninitialized hash function
builtin/hash-object: fix uninitialized hash function
builtin/patch-id: fix uninitialized hash function
t1517: test commands that are designed to be run outside repository
setup: add an escape hatch for "no more default hash algorithm" change
Junio C Hamano [Thu, 30 May 2024 21:15:12 +0000 (14:15 -0700)]
Merge branch 'ps/reftable-reusable-iterator'
Code clean-up to make the reftable iterator closer to be reusable.
* ps/reftable-reusable-iterator:
reftable/merged: adapt interface to allow reuse of iterators
reftable/stack: provide convenience functions to create iterators
reftable/reader: adapt interface to allow reuse of iterators
reftable/generic: adapt interface to allow reuse of iterators
reftable/generic: move seeking of records into the iterator
reftable/merged: simplify indices for subiterators
reftable/merged: split up initialization and seeking of records
reftable/reader: set up the reader when initializing table iterator
reftable/reader: inline `reader_seek_internal()`
reftable/reader: separate concerns of table iter and reftable reader
reftable/reader: unify indexed and linear seeking
reftable/reader: avoid copying index iterator
reftable/block: use `size_t` to track restart point index
Junio C Hamano [Thu, 30 May 2024 21:15:11 +0000 (14:15 -0700)]
Merge branch 'ps/reftable-write-options'
The knobs to tweak how reftable files are written have been made
available as configuration variables.
* ps/reftable-write-options:
refs/reftable: allow configuring geometric factor
reftable: make the compaction factor configurable
refs/reftable: allow disabling writing the object index
refs/reftable: allow configuring restart interval
reftable: use `uint16_t` to track restart interval
refs/reftable: allow configuring block size
reftable/dump: support dumping a table's block structure
reftable/writer: improve error when passed an invalid block size
reftable/writer: drop static variable used to initialize strbuf
reftable: pass opts as constant pointer
reftable: consistently refer to `reftable_write_options` as `opts`
Before discovering the repository details, We used to assume SHA-1
as the "default" hash function, which has been corrected. Hopefully
this will smoke out codepaths that rely on such an unwarranted
assumptions.
* ps/undecided-is-not-necessarily-sha1:
repository: stop setting SHA1 as the default object hash
oss-fuzz/commit-graph: set up hash algorithm
builtin/shortlog: don't set up revisions without repo
builtin/diff: explicitly set hash algo when there is no repo
builtin/bundle: abort "verify" early when there is no repository
builtin/blame: don't access potentially unitialized `the_hash_algo`
builtin/rev-parse: allow shortening to more than 40 hex characters
remote-curl: fix parsing of detached SHA256 heads
attr: fix BUG() when parsing attrs outside of repo
attr: don't recompute default attribute source
parse-options-cb: only abbreviate hashes when hash algo is known
path: move `validate_headref()` to its only user
path: harden validation of HEAD with non-standard hashes
Junio C Hamano [Wed, 29 May 2024 16:32:24 +0000 (09:32 -0700)]
Merge branch 'ps/leakfixes' into ps/no-writable-strings
* ps/leakfixes:
builtin/mv: fix leaks for submodule gitfile paths
builtin/mv: refactor to use `struct strvec`
builtin/mv duplicate string list memory
builtin/mv: refactor `add_slash()` to always return allocated strings
strvec: add functions to replace and remove strings
submodule: fix leaking memory for submodule entries
commit-reach: fix memory leak in `ahead_behind()`
builtin/credential: clear credential before exit
config: plug various memory leaks
config: clarify memory ownership in `git_config_string()`
builtin/log: stop using globals for format config
builtin/log: stop using globals for log config
convert: refactor code to clarify ownership of check_roundtrip_encoding
diff: refactor code to clarify memory ownership of prefixes
config: clarify memory ownership in `git_config_pathname()`
http: refactor code to clarify memory ownership
checkout: clarify memory ownership in `unique_tracking_name()`
strbuf: fix leak when `appendwholeline()` fails with EOF
transport-helper: fix leaking helper name
The credential helper that talks with osx keychain learned to avoid
storing back the authentication material it just got received from
the keychain.
* kn/osxkeychain-skip-idempotent-store:
osxkeychain: state to skip unnecessary store operations
osxkeychain: exclusive lock to serialize execution of operations
Junio C Hamano [Tue, 28 May 2024 18:17:07 +0000 (11:17 -0700)]
Merge branch 'ps/builtin-config-cleanup'
Code clean-up to reduce inter-function communication inside
builtin/config.c done via the use of global variables.
* ps/builtin-config-cleanup: (21 commits)
builtin/config: pass data between callbacks via local variables
builtin/config: convert flags to a local variable
builtin/config: track "fixed value" option via flags only
builtin/config: convert `key` to a local variable
builtin/config: convert `key_regexp` to a local variable
builtin/config: convert `regexp` to a local variable
builtin/config: convert `value_pattern` to a local variable
builtin/config: convert `do_not_match` to a local variable
builtin/config: move `respect_includes_opt` into location options
builtin/config: move default value into display options
builtin/config: move type options into display options
builtin/config: move display options into local variables
builtin/config: move location options into local variables
builtin/config: refactor functions to have common exit paths
config: make the config source const
builtin/config: check for writeability after source is set up
builtin/config: move actions into `cmd_config_actions()`
builtin/config: move legacy options into `cmd_config()`
builtin/config: move subcommand options into `cmd_config()`
builtin/config: move legacy mode into its own function
...
Junio C Hamano [Tue, 28 May 2024 18:17:06 +0000 (11:17 -0700)]
Merge branch 'ps/pseudo-ref-terminology'
Terminology to call various ref-like things are getting
straightened out.
* ps/pseudo-ref-terminology:
refs: refuse to write pseudorefs
ref-filter: properly distinuish pseudo and root refs
refs: pseudorefs are no refs
refs: classify HEAD as a root ref
refs: do not check ref existence in `is_root_ref()`
refs: rename `is_special_ref()` to `is_pseudo_ref()`
refs: rename `is_pseudoref()` to `is_root_ref()`
Documentation/glossary: define root refs as refs
Documentation/glossary: clarify limitations of pseudorefs
Documentation/glossary: redefine pseudorefs as special refs
Similar to the preceding commit, we have effectively given tracking
memory ownership of submodule gitfile paths. Refactor the code to start
tracking allocated strings in a separate `struct strvec` such that we
can easily plug those leaks. Mark now-passing tests as leak free.
Note that ideally, we wouldn't require two separate data structures to
track those paths. But we do need to store `NULL` pointers for the
gitfile paths such that we can indicate that its corresponding entries
in the other arrays do not have such a path at all. And given that
`struct strvec`s cannot store `NULL` pointers we cannot use them to
store this information.
There is another small gotcha that is easy to miss: you may be wondering
why we don't want to store `SUBMODULE_WITH_GITDIR` in the strvec. This
is because this is a mere sentinel value and not actually a string at
all.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Memory allocation patterns in git-mv(1) are extremely hard to follow:
We copy around string pointers into manually-managed arrays, some of
which alias each other, but only sometimes, while we also drop some of
those strings at other times without ever daring to free them.
While this may be my own subjective feeling, it seems like others have
given up as the code has multiple calls to `UNLEAK()`. These are not
sufficient though, and git-mv(1) is still leaking all over the place
even with them.
Refactor the code to instead track strings in `struct strvec`. While
this has the effect of effectively duplicating some of the strings
without an actual need, it is way easier to reason about and fixes all
of the aliasing of memory that has been going on. It allows us to get
rid of the `UNLEAK()` calls and also fixes leaks that those calls did
not paper over.
Mark tests which are now leak-free accordingly.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
makes the next patch easier, where we will migrate to the paths being
owned by a strvec. given that we are talking about command line
parameters here it's also not like we have tons of allocations that this
would save
while at it, fix a memory leak
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/mv: refactor `add_slash()` to always return allocated strings
The `add_slash()` function will only conditionally return an allocated
string when the passed-in string did not yet have a trailing slash. This
makes the memory ownership harder to track than really necessary.
It's dubious whether this optimization really buys us all that much. The
number of times we execute this function is bounded by the number of
arguments to git-mv(1), so in the typical case we may end up saving an
allocation or two.
Simplify the code to unconditionally return allocated strings.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule: fix leaking memory for submodule entries
In `free_one_config()` we never end up freeing the `url` and `ignore`
fields and thus leak memory. Fix those leaks and mark now-passing tests
as leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use a priority queue in `ahead_behind()` to compute the ahead/behind
count for commits. We may not iterate through all commits part of that
queue though in case all of its entries are stale. Consequently, as we
never make the effort to release the remaining commits, we end up
leaking bit arrays that we have allocated for each of the contained
commits.
Plug this leak and mark the corresponding test as leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that memory ownership rules around `git_config_string()` and
`git_config_pathname()` are clearer, it also got easier to spot that
the returned memory needs to be free'd. Plug a subset of those cases and
mark now-passing tests as leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: clarify memory ownership in `git_config_string()`
The out parameter of `git_config_string()` is a `const char **` even
though we transfer ownership of memory to the caller. This is quite
misleading and has led to many memory leaks all over the place. Adapt
the parameter to instead be `char **`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We're using global variables to store the log configuration. Many of
these can be set both via the command line and via the config, and
depending on how they are being set, they may contain allocated strings.
This leads to hard-to-track memory ownership and memory leaks.
Refactor the code to instead use a `struct log_config` that is being
allocated on the stack. This allows us to more clearly scope the
variables, track memory ownership and ultimately release the memory.
This also prepares us for a change to `git_config_string()`, which will
be adapted to have a `char **` out parameter instead of `const char **`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
convert: refactor code to clarify ownership of check_roundtrip_encoding
The `check_roundtrip_encoding` variable is tracked in a `const char *`
even though it may contain allocated strings at times. The result is
that those strings may be leaking because we never free them.
Refactor the code to always store allocated strings in this variable.
The default value is handled in `check_roundtrip()` now, which is the
only user of the variable.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff: refactor code to clarify memory ownership of prefixes
The source and destination prefixes are tracked in a `const char *`
array, but may at times contain allocated strings. The result is that
those strings may be leaking because we never free them.
Refactor the code to always store allocated strings in those variables,
freeing them as required. This requires us to handle the default values
a bit different compared to before. But given that there is only a
single callsite where we use the variables to `struct diff_options` it's
easy to handle the defaults there.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: clarify memory ownership in `git_config_pathname()`
The out parameter of `git_config_pathname()` is a `const char **` even
though we transfer ownership of memory to the caller. This is quite
misleading and has led to many memory leaks all over the place. Adapt
the parameter to instead be `char **`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are various variables assigned via `git_config_string()` and
`git_config_pathname()` which are never free'd. This bug is relatable
because the out parameter of those functions are a `const char **`, even
though memory ownership is transferred to the caller.
We're about to adapt the functions to instead use `char **`. Prepare the
code accordingly. Note that the `(const char **)` casts will go away
once we have adapted the functions.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout: clarify memory ownership in `unique_tracking_name()`
The function `unique_tracking_name()` returns an allocated string, but
does not clearly indicate this because its return type is `const char *`
instead of `char *`. This has led to various callsites where we never
free its returned memory at all, which causes memory leaks.
Plug those leaks and mark now-passing tests as leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
strbuf: fix leak when `appendwholeline()` fails with EOF
In `strbuf_appendwholeline()` we call `strbuf_getwholeline()` with a
temporary buffer. In case the call returns an error we indicate this by
returning EOF, but never release the temporary buffer. This can cause a
leak though because `strbuf_getwholeline()` calls getline(3). Quoting
its documentation:
If *lineptr was set to NULL before the call, then the buffer
should be freed by the user program even on failure.
Consequently, the temporary buffer may hold allocated memory even when
the call to `strbuf_getwholeline()` fails.
Fix this by releasing the temporary buffer on error.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
- t7423: Introduced via b20c10fd9b (t7423: add tests for symlinked
submodule directories, 2024-01-28), passes since e8d0608944
(submodule: require the submodule path to contain directories only,
2024-03-26). The fix is not obviously related, but probably works
because we now die early in many code paths.
- t9xxx: All of these are exercising CVS-related tooling and pass
since at least Git v2.40. It's likely that these pass for a long
time already, but nobody ever noticed because Git developers do not
tend to have CVS on their machines.
Mark all of these tests as passing.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When initializing the transport helper in `transport_get()`, we
allocate the name of the helper. We neither end up transferring
ownership of the name, nor do we free it. The associated memory thus
leaks.
Fix this memory leak by freeing the string at the calling side in
`transport_get()`. `transport_helper_init()` now creates its own copy of
the string and thus can free it as required.
An alterantive way to fix this would be to transfer ownership of the
string passed into `transport_helper_init()`, which would avoid the call
to xstrdup(1). But it does make for a more surprising calling convention
as we do not typically transfer ownership of strings like this.
Mark now-passing tests as leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In "t/lib-terminal.sh", we declare a lazy prerequisite for tests that
require a TTY. The prerequisite uses a Perl script to figure out whether
we do have a usable TTY or not and thus implicitly depends on the PERL
prerequisite, as well. Furthermore though, the script requires another
dependency that is easy to miss, namely on the IO::Pty module. If that
module is not installed, then the script will exit early due to an
reason unrelated to missing TTYs.
This easily leads to missing test coverage. But most importantly, our CI
systems are missing this dependency and thus don't execute those tests
at all. Fix this.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Thu, 23 May 2024 18:04:29 +0000 (11:04 -0700)]
Merge branch 'mt/openindiana-portability'
Portability updates to various uses of grep and sed.
* mt/openindiana-portability:
t/t9001-send-email.sh: sed - remove the i flag for s
t/t9118-git-svn-funky-branch-names.sh: sed needs semicolon
t/t1700-split-index.sh: mv -v is not portable
t/t4202-log.sh: fix misspelled variable
t/t0600-reffiles-backend.sh: rm -v is not portable
t/t9902-completion.sh: backslashes in echo
Switch grep from non-portable BRE to portable ERE
Junio C Hamano [Thu, 23 May 2024 18:04:26 +0000 (11:04 -0700)]
Merge branch 'la/hide-trailer-info'
The trailer API has been reshuffled a bit.
* la/hide-trailer-info:
trailer unit tests: inspect iterator contents
trailer: document parse_trailers() usage
trailer: retire trailer_info_get() from API
trailer: make trailer_info struct private
trailer: make parse_trailers() return trailer_info pointer
interpret-trailers: access trailer_info with new helpers
sequencer: use the trailer iterator
trailer: teach iterator about non-trailer lines
trailer: add unit tests for trailer iterator
Makefile: sort UNIT_TEST_PROGRAMS
Junio C Hamano [Mon, 20 May 2024 23:14:34 +0000 (16:14 -0700)]
apply: fix uninitialized hash function
"git apply" can work outside a repository as a better "GNU patch",
but when it does so, it still assumed that it can access
the_hash_algo, which is no longer true in the new world order.
Make sure we explicitly fall back to SHA-1 algorithm for backward
compatibility.
It is of dubious value to make this configurable to other hash
algorithms, as the code does not use the_hash_algo for hashing
purposes when working outside a repository (which is how
the_hash_algo is left to NULL)---it is only used to learn the max
length of the hash when parsing the object names on the "index"
line, but failing to parse the "index" line is not a hard failure,
and the program does not support operations like applying binary
patches and --3way fallback that requires object access outside a
repository.
builtin/hash-object: fix uninitialized hash function
The git-hash-object(1) command allows users to hash an object even
without a repository. Starting with c8aed5e8da (repository: stop setting
SHA1 as the default object hash, 2024-05-07), this will make us hit an
uninitialized hash function, which subsequently leads to a segfault.
Fix this by falling back to SHA-1 explicitly when running outside of
a Git repository. Users can use GIT_DEFAULT_HASH environment to
specify what hash algorithm they want, so arguably this code should
not be needed.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In c8aed5e8da (repository: stop setting SHA1 as the default object hash,
2024-05-07), we have adapted `initialize_repository()` to no longer set
up a default hash function. As this function is also used to set up
`the_repository`, the consequence is that `the_hash_algo` will now by
default be a `NULL` pointer unless the hash algorithm was configured
properly. This is done as a mechanism to detect cases where we may be
using the wrong hash function by accident.
This change now causes git-patch-id(1) to segfault when it's run outside
of a repository. As this command can read diffs from stdin, it does not
necessarily need a repository, but then relies on `the_hash_algo` to
compute the patch ID itself.
It is somewhat dubious that git-patch-id(1) relies on `the_hash_algo` in
the first place. Quoting its manpage:
A "patch ID" is nothing but a sum of SHA-1 of the file diffs
associated with a patch, with line numbers ignored. As such, it’s
"reasonably stable", but at the same time also reasonably unique,
i.e., two patches that have the same "patch ID" are almost
guaranteed to be the same thing.
We explicitly document patch IDs to be using SHA-1. Furthermore, patch
IDs are supposed to be stable for most of the part. But even with the
same input, the patch IDs will now be different depending on the repo's
configured object hash.
Work around the issue by setting up SHA-1 when there was no startup
repository for now. This is arguably not the correct fix, but for now we
rather want to focus on getting the segfault fixed.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Mon, 20 May 2024 23:14:31 +0000 (16:14 -0700)]
t1517: test commands that are designed to be run outside repository
A few commands, like "git apply" and "git patch-id", have been
broken with a recent change to stop setting the default hash
algorithm to SHA-1. Test them and fix them in later commits.
Junio C Hamano [Mon, 20 May 2024 23:14:30 +0000 (16:14 -0700)]
setup: add an escape hatch for "no more default hash algorithm" change
Partially revert c8aed5e8 (repository: stop setting SHA1 as the
default object hash, 2024-05-07), to keep end-user systems still
broken when we have gap in our test coverage but yet give them an
escape hatch to set the GIT_TEST_DEFAULT_HASH_ALGO environment
variable to "sha1" in order to revert to the previous behaviour, in
case we haven't done a thorough job in fixing the fallout from c8aed5e8. After we build confidence, we should remove the escape
hatch support, but we are not there yet after only fixing three
commands (hash-object, apply, and patch-id) in this series.
Due to the way the end-user facing GIT_DEFAULT_HASH environment
variable is used in our test suite, we unfortunately cannot reuse it
for this purpose.
Junio C Hamano [Mon, 20 May 2024 18:20:04 +0000 (11:20 -0700)]
Merge branch 'jc/compat-regex-calloc-fix'
Windows CI running in GitHub Actions started complaining about the
order of arguments given to calloc(); the imported regex code uses
the wrong order almost consistently, which has been corrected.
* jc/compat-regex-calloc-fix:
compat/regex: fix argument order to calloc(3)
Junio C Hamano [Mon, 20 May 2024 18:20:04 +0000 (11:20 -0700)]
Merge branch 'kn/ref-transaction-symref'
Updates to symbolic refs can now be made as a part of ref
transaction.
* kn/ref-transaction-symref:
refs: remove `create_symref` and associated dead code
refs: rename `refs_create_symref()` to `refs_update_symref()`
refs: use transaction in `refs_create_symref()`
refs: add support for transactional symref updates
refs: move `original_update_refname` to 'refs.c'
refs: support symrefs in 'reference-transaction' hook
files-backend: extract out `create_symref_lock()`
refs: accept symref values in `ref_transaction_update()`
Marcel Telka [Fri, 17 May 2024 15:27:41 +0000 (17:27 +0200)]
t/t1700-split-index.sh: mv -v is not portable
The -v option for mv is not specified by POSIX. The illumos
implementation of mv does not support -v. Since we do not need the
verbose mv output we just drop -v for mv.
Signed-off-by: Marcel Telka <marcel@telka.sk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Marcel Telka [Fri, 17 May 2024 13:19:00 +0000 (15:19 +0200)]
t/t0600-reffiles-backend.sh: rm -v is not portable
The -v option for rm is not specified by POSIX. The illumos
implementation of rm does not support -v. Since we do not need the
verbose rm output we just drop -v for rm.
Signed-off-by: Marcel Telka <marcel@telka.sk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Marcel Telka [Fri, 17 May 2024 14:08:45 +0000 (16:08 +0200)]
t/t9902-completion.sh: backslashes in echo
The usage of backslashes in echo is not portable. Since some tests
tries to output strings containing '\b' it is safer to use printf
here. The usage of printf instead of echo is also preferred by POSIX.
Signed-off-by: Marcel Telka <marcel@telka.sk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Fri, 17 May 2024 17:14:46 +0000 (10:14 -0700)]
diff: document what --name-only shows
The "--name-only" option is about showing the name of each file in
the post-image tree that got changed and nothing else (like "was it
created?"). Unlike the "--name-status" option that tells how the
change happened (e.g., renamed with similarity), it does not give
anything else, like the name of the corresponding file in the old
tree.
For example, if you start from a clean checkout that has a file
whose name is COPYING, here is what you would see:
Lack of the description of this fact has confused readers in the
past. Even back when dda2d79a ([PATCH] Clean up diff option
descriptions., 2005-07-13) documented "--name-only", "git diff"
already supported the renames, so in a sense, from day one, this
should have been documented more clearly but it wasn't.