Commit Graph

469 Commits

Author SHA1 Message Date
Junio C Hamano
68f95b26e4 Sync with Git 2.16.4
* maint-2.16:
  Git 2.16.4
  Git 2.15.2
  Git 2.14.4
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:25:26 +09:00
Junio C Hamano
023020401d Sync with Git 2.15.2
* maint-2.15:
  Git 2.15.2
  Git 2.14.4
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:18:06 +09:00
Junio C Hamano
9e0f06d55d Sync with Git 2.14.4
* maint-2.14:
  Git 2.14.4
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:15:14 +09:00
Junio C Hamano
7b01c71b64 Sync with Git 2.13.7
* maint-2.13:
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:10:49 +09:00
Jeff King
41a80924ae skip_prefix: add case-insensitive variant
We have the convenient skip_prefix() helper, but if you want
to do case-insensitive matching, you're stuck doing it by
hand. We could add an extra parameter to the function to
let callers ask for this, but the function is small and
somewhat performance-critical. Let's just re-implement it
for the case-insensitive version.

Signed-off-by: Jeff King <peff@peff.net>
2018-05-21 23:50:11 -04:00
Brandon Williams
eb78e23f22 wrapper: rename 'template' variables
Rename C++ keyword in order to bring the codebase closer to being able
to be compiled with a C++ compiler.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-02-22 10:08:05 -08:00
Christian Couder
afaef55e23 git-compat-util: introduce skip_to_optional_arg()
We often accept both a "--key" option and a "--key=<val>" option.

These options currently are parsed using something like:

if (!strcmp(arg, "--key")) {
	/* do something */
} else if (skip_prefix(arg, "--key=", &arg)) {
	/* do something with arg */
}

which is a bit cumbersome compared to just:

if (skip_to_optional_arg(arg, "--key", &arg)) {
	/* do something with arg */
}

This also introduces skip_to_optional_arg_default() for the few
cases where something different should be done when the first
argument is exactly "--key" than when it is exactly "--key=".

In general it is better for UI consistency and simplicity if
"--key" and "--key=" do the same thing though, so that using
skip_to_optional_arg() should be encouraged compared to
skip_to_optional_arg_default().

Note that these functions can be used to parse any "key=value"
string where "key" is also considered as valid, not just
command line options.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-11 16:10:12 -08:00
Junio C Hamano
14a8168e2f Merge branch 'rj/no-sign-compare'
Many codepaths have been updated to squelch -Wsign-compare
warnings.

* rj/no-sign-compare:
  ALLOC_GROW: avoid -Wsign-compare warnings
  cache.h: hex2chr() - avoid -Wsign-compare warnings
  commit-slab.h: avoid -Wsign-compare warnings
  git-compat-util.h: xsize_t() - avoid -Wsign-compare warnings
2017-09-29 11:23:42 +09:00
Ramsay Jones
73560c793a git-compat-util.h: xsize_t() - avoid -Wsign-compare warnings
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-22 13:00:33 +09:00
Jonathan Tan
5de3de329a git-compat-util: make UNLEAK less error-prone
Commit 0e5bba5 ("add UNLEAK annotation for reducing leak false
positives", 2017-09-08) introduced an UNLEAK macro to be used as
"UNLEAK(var);", but its existing definitions leave semicolons that act
as empty statements, which will lead to syntax errors, e.g.

	if (condition)
		UNLEAK(var);
	else
		something_else(var);

would be broken with two statements between if (condition) and else.
Lose the excess semicolon from the end of the macro replacement text.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-20 15:00:41 +09:00
Jeff King
0e5bba53af add UNLEAK annotation for reducing leak false positives
It's a common pattern in git commands to allocate some
memory that should last for the lifetime of the program and
then not bother to free it, relying on the OS to throw it
away.

This keeps the code simple, and it's fast (we don't waste
time traversing structures or calling free at the end of the
program). But it also triggers warnings from memory-leak
checkers like valgrind or LSAN. They know that the memory
was still allocated at program exit, but they don't know
_when_ the leaked memory stopped being useful. If it was
early in the program, then it's probably a real and
important leak. But if it was used right up until program
exit, it's not an interesting leak and we'd like to suppress
it so that we can see the real leaks.

This patch introduces an UNLEAK() macro that lets us do so.
To understand its design, let's first look at some of the
alternatives.

Unfortunately the suppression systems offered by
leak-checking tools don't quite do what we want. A
leak-checker basically knows two things:

  1. Which blocks were allocated via malloc, and the
     callstack during the allocation.

  2. Which blocks were left un-freed at the end of the
     program (and which are unreachable, but more on that
     later).

Their suppressions work by mentioning the function or
callstack of a particular allocation, and marking it as OK
to leak.  So imagine you have code like this:

  int cmd_foo(...)
  {
	/* this allocates some memory */
	char *p = some_function();
	printf("%s", p);
	return 0;
  }

You can say "ignore allocations from some_function(),
they're not leaks". But that's not right. That function may
be called elsewhere, too, and we would potentially want to
know about those leaks.

So you can say "ignore the callstack when main calls
some_function".  That works, but your annotations are
brittle. In this case it's only two functions, but you can
imagine that the actual allocation is much deeper. If any of
the intermediate code changes, you have to update the
suppression.

What we _really_ want to say is that "the value assigned to
p at the end of the function is not a real leak". But
leak-checkers can't understand that; they don't know about
"p" in the first place.

However, we can do something a little bit tricky if we make
some assumptions about how leak-checkers work. They
generally don't just report all un-freed blocks. That would
report even globals which are still accessible when the
leak-check is run.  Instead they take some set of memory
(like BSS) as a root and mark it as "reachable". Then they
scan the reachable blocks for anything that looks like a
pointer to a malloc'd block, and consider that block
reachable. And then they scan those blocks, and so on,
transitively marking anything reachable from a global as
"not leaked" (or at least leaked in a different category).

So we can mark the value of "p" as reachable by putting it
into a variable with program lifetime. One way to do that is
to just mark "p" as static. But that actually affects the
run-time behavior if the function is called twice (you
aren't likely to call main() twice, but some of our cmd_*()
functions are called from other commands).

Instead, we can trick the leak-checker by putting the value
into _any_ reachable bytes. This patch keeps a global
linked-list of bytes copied from "unleaked" variables. That
list is reachable even at program exit, which confers
recursive reachability on whatever values we unleak.

In other words, you can do:

  int cmd_foo(...)
  {
	char *p = some_function();
	printf("%s", p);
	UNLEAK(p);
	return 0;
  }

to annotate "p" and suppress the leak report.

But wait, couldn't we just say "free(p)"? In this toy
example, yes. But UNLEAK()'s byte-copying strategy has
several advantages over actually freeing the memory:

  1. It's recursive across structures. In many cases our "p"
     is not just a pointer, but a complex struct whose
     fields may have been allocated by a sub-function. And
     in some cases (e.g., dir_struct) we don't even have a
     function which knows how to free all of the struct
     members.

     By marking the struct itself as reachable, that confers
     reachability on any pointers it contains (including those
     found in embedded structs, or reachable by walking
     heap blocks recursively.

  2. It works on cases where we're not sure if the value is
     allocated or not. For example:

       char *p = argc > 1 ? argv[1] : some_function();

     It's safe to use UNLEAK(p) here, because it's not
     freeing any memory. In the case that we're pointing to
     argv here, the reachability checker will just ignore
     our bytes.

  3. Likewise, it works even if the variable has _already_
     been freed. We're just copying the pointer bytes. If
     the block has been freed, the leak-checker will skip
     over those bytes as uninteresting.

  4. Because it's not actually freeing memory, you can
     UNLEAK() before we are finished accessing the variable.
     This is helpful in cases like this:

       char *p = some_function();
       return another_function(p);

     Writing this with free() requires:

       int ret;
       char *p = some_function();
       ret = another_function(p);
       free(p);
       return ret;

     But with unleak we can just write:

       char *p = some_function();
       UNLEAK(p);
       return another_function(p);

This patch adds the UNLEAK() macro and enables it
automatically when Git is compiled with SANITIZE=leak.  In
normal builds it's a noop, so we pay no runtime cost.

It also adds some UNLEAK() annotations to show off how the
feature works. On top of other recent leak fixes, these are
enough to get t0000 and t0001 to pass when compiled with
LSAN.

Note the case in commit.c which actually converts a
strbuf_release() into an UNLEAK. This code was already
non-leaky, but the free didn't do anything useful, since
we're exiting. Converting it to an annotation means that
non-leak-checking builds pay no runtime cost. The cost is
minimal enough that it's probably not worth going on a
crusade to convert these kinds of frees to UNLEAKS. I did it
here for consistency with the "sb" leak (though it would
have been equally correct to go the other way, and turn them
both into strbuf_release() calls).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-08 15:43:17 +09:00
Jonathan Tan
f0e17e86e1 pack: move release_pack_memory()
The function unuse_one_window() needs to be temporarily made global. Its
scope will be restored to static in a subsequent commit.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-23 15:12:06 -07:00
Junio C Hamano
d3b7ee087e Merge branch 'rs/move-array' into maint
Code clean-up.

* rs/move-array:
  ls-files: don't try to prune an empty index
  apply: use COPY_ARRAY and MOVE_ARRAY in update_image()
  use MOVE_ARRAY
  add MOVE_ARRAY
2017-08-23 14:33:46 -07:00
Junio C Hamano
32f90258bd Merge branch 'rs/move-array'
Code clean-up.

* rs/move-array:
  ls-files: don't try to prune an empty index
  apply: use COPY_ARRAY and MOVE_ARRAY in update_image()
  use MOVE_ARRAY
  add MOVE_ARRAY
2017-08-11 13:26:57 -07:00
Junio C Hamano
33400c0e96 Merge branch 'tb/push-to-cygwin-unc-path'
On Cygwin, similar to Windows, "git push //server/share/repository"
ought to mean a repository on a network share that can be accessed
locally, but this did not work correctly due to stripping the double
slashes at the beginning.

This may need to be heavily tested before it gets unleashed to the
wild, as the change is at a fairly low-level code and would affect
not just the code to decide if the push destination is local.  There
may be unexpected fallouts in the path normalization.

* tb/push-to-cygwin-unc-path:
  cygwin: allow pushing to UNC paths
2017-07-18 12:48:09 -07:00
René Scharfe
578398071e add MOVE_ARRAY
Similar to COPY_ARRAY (introduced in 60566cbb58), add a safe and
convenient helper for moving potentially overlapping ranges of array
entries.  It infers the element size, multiplies automatically and
safely to get the size in bytes, does a basic type safety check by
comparing element sizes and unlike memmove(3) it supports NULL
pointers iff 0 elements are to be moved.

Also add a semantic patch to demonstrate the helper's intended usage.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-17 14:54:53 -07:00
Torsten Bögershausen
496f256989 cygwin: allow pushing to UNC paths
cygwin can use an UNC path like //server/share/repo

 $ cd //server/share/dir
 $ mkdir test
 $ cd test
 $ git init --bare

 However, when we try to push from a local Git repository to this repo,
 there is a problem: Git converts the leading "//" into a single "/".

 As cygwin handles an UNC path so well, Git can support them better:

 - Introduce cygwin_offset_1st_component() which keeps the leading "//",
   similar to what Git for Windows does.

 - Move CYGWIN out of the POSIX in the tests for path normalization in t0060

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-05 14:01:03 -07:00
Ævar Arnfjörð Bjarmason
481df65f4f git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL
Add a FREE_AND_NULL() wrapper marco for the common pattern of freeing
a pointer and assigning NULL to it right afterwards.

The implementation is similar to the (currently unused) XDL_PTRFREE
macro in xdiff/xmacros.h added in commit 3443546f6e ("Use a *real*
built-in diff generator", 2006-03-24). The only difference is that
free() is called unconditionally, see [1].

See [2] for a suggested alternative which does this via a function
instead of a macro. As covered in replies to that message, while it's
a viable approach, it would introduce caveats which this approach
doesn't have, so that potential change is left to a future follow-up
change.

This merely allows us to translate exactly what we're doing now to a
less verbose & idiomatic form using a macro, while guaranteeing that
we don't introduce any functional changes.

1. <alpine.DEB.2.20.1608301948310.129229@virtualbox>
   (http://public-inbox.org/git/alpine.DEB.2.20.1608301948310.129229@virtualbox/)

2. <20170610032143.GA7880@starla>
   (https://public-inbox.org/git/20170610032143.GA7880@starla/)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15 14:56:39 -07:00
Junio C Hamano
b9a7d55d93 Merge branch 'nd/fopen-errors'
We often try to open a file for reading whose existence is
optional, and silently ignore errors from open/fopen; report such
errors if they are not due to missing files.

* nd/fopen-errors:
  mingw_fopen: report ENOENT for invalid file names
  mingw: verify that paths are not mistaken for remote nicknames
  log: fix memory leak in open_next_file()
  rerere.c: move error_errno() closer to the source system call
  print errno when reporting a system call error
  wrapper.c: make warn_on_inaccessible() static
  wrapper.c: add and use fopen_or_warn()
  wrapper.c: add and use warn_on_fopen_errors()
  config.mak.uname: set FREAD_READS_DIRECTORIES for Darwin, too
  config.mak.uname: set FREAD_READS_DIRECTORIES for Linux and FreeBSD
  clone: use xfopen() instead of fopen()
  use xfopen() in more places
  git_fopen: fix a sparse 'not declared' warning
2017-06-13 13:47:09 -07:00
Junio C Hamano
93dd544f54 Merge branch 'jc/noent-notdir'
Our code often opens a path to an optional file, to work on its
contents when we can successfully open it.  We can ignore a failure
to open if such an optional file does not exist, but we do want to
report a failure in opening for other reasons (e.g. we got an I/O
error, or the file is there, but we lack the permission to open).

The exact errors we need to ignore are ENOENT (obviously) and
ENOTDIR (less obvious).  Instead of repeating comparison of errno
with these two constants, introduce a helper function to do so.

* jc/noent-notdir:
  treewide: use is_missing_file_error() where ENOENT and ENOTDIR are checked
  compat-util: is_missing_file_error()
2017-06-13 13:47:07 -07:00
Junio C Hamano
e350625b68 Merge branch 'bw/forking-and-threading' into maint
The "run-command" API implementation has been made more robust
against dead-locking in a threaded environment.

* bw/forking-and-threading:
  usage.c: drop set_error_handle()
  run-command: restrict PATH search to executable files
  run-command: expose is_executable function
  run-command: block signals between fork and execve
  run-command: add note about forking and threading
  run-command: handle dup2 and close errors in child
  run-command: eliminate calls to error handling functions in child
  run-command: don't die in child when duping /dev/null
  run-command: prepare child environment before forking
  string-list: add string_list_remove function
  run-command: use the async-signal-safe execv instead of execvp
  run-command: prepare command before forking
  t0061: run_command executes scripts without a #! line
  t5550: use write_script to generate post-update hook
2017-06-13 13:27:00 -07:00
Junio C Hamano
7d5e13f652 Merge branch 'bw/forking-and-threading'
The "run-command" API implementation has been made more robust
against dead-locking in a threaded environment.

* bw/forking-and-threading:
  usage.c: drop set_error_handle()
  run-command: restrict PATH search to executable files
  run-command: expose is_executable function
  run-command: block signals between fork and execve
  run-command: add note about forking and threading
  run-command: handle dup2 and close errors in child
  run-command: eliminate calls to error handling functions in child
  run-command: don't die in child when duping /dev/null
  run-command: prepare child environment before forking
  string-list: add string_list_remove function
  run-command: use the async-signal-safe execv instead of execvp
  run-command: prepare command before forking
  t0061: run_command executes scripts without a #! line
  t5550: use write_script to generate post-update hook
2017-05-30 11:16:41 +09:00
Junio C Hamano
dc5a18b364 compat-util: is_missing_file_error()
Our code often opens a path to an optional file, to work on its
contents when we can successfully open it.  We can ignore a failure
to open if such an optional file does not exist, but we do want to
report a failure in opening for other reasons (e.g. we got an I/O
error, or the file is there, but we lack the permission to open).

The exact errors we need to ignore are ENOENT (obviously) and
ENOTDIR (less obvious).  Instead of repeating comparison of errno
with these two constants, introduce a helper function to do so.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-30 09:14:39 +09:00
Junio C Hamano
220c6a7080 Merge branch 'jk/bug-to-abort'
Introduce the BUG() macro to improve die("BUG: ...").

* jk/bug-to-abort:
  usage: add NORETURN to BUG() function definitions
  config: complain about --local outside of a git repo
  setup_git_env: convert die("BUG") to BUG()
  usage.c: add BUG() function
2017-05-29 12:34:45 +09:00
Nguyễn Thái Ngọc Duy
382fb07f7b wrapper.c: make warn_on_inaccessible() static
After the last patch, this function is not used outside anymore. Keep it
static.

Noticed-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:56 +09:00
Nguyễn Thái Ngọc Duy
e9d983f116 wrapper.c: add and use fopen_or_warn()
When fopen() returns NULL, it could be because the given path does not
exist, but it could also be some other errors and the caller has to
check. Add a wrapper so we don't have to repeat the same error check
everywhere.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:56 +09:00
Nguyễn Thái Ngọc Duy
11dc1fcb3f wrapper.c: add and use warn_on_fopen_errors()
In many places, Git warns about an inaccessible file after a fopen()
failed. To discern these cases from other cases where we want to warn
about inaccessible files, introduce a new helper specifically to test
whether fopen() failed because the current user lacks the permission to
open file in question.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:55 +09:00
Ramsay Jones
b0a642ac46 git_fopen: fix a sparse 'not declared' warning
If git is built with the FREAD_READS_DIRECTORIES build variable set, this
would cause sparse to issue a 'not declared, should it be static?' warning
on Linux. This is a result of the method employed by 'compat/fopen.c' to
suppress the (possible) redefinition of the (system) fopen macro, which
also removes the extern declaration of the git_fopen function.

In order to suppress the warning, introduce a new macro to suppress the
definition (or possibly the re-definition) of the fopen symbol as a macro
override. This new macro (SUPPRESS_FOPEN_REDEFINITION) is only defined in
'compat/fopen.c', just prior to the inclusion of the 'git-compat-util.h'
header file.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:55 +09:00
Junio C Hamano
b15667bbdc Merge branch 'js/larger-timestamps'
Some platforms have ulong that is smaller than time_t, and our
historical use of ulong for timestamp would mean they cannot
represent some timestamp that the platform allows.  Invent a
separate and dedicated timestamp_t (so that we can distingiuish
timestamps and a vanilla ulongs, which along is already a good
move), and then declare uintmax_t is the type to be used as the
timestamp_t.

* js/larger-timestamps:
  archive-tar: fix a sparse 'constant too large' warning
  use uintmax_t for timestamps
  date.c: abort if the system time cannot handle one of our timestamps
  timestamp_t: a new data type for timestamps
  PRItime: introduce a new "printf format" for timestamps
  parse_timestamp(): specify explicitly where we parse timestamps
  t0006 & t5000: skip "far in the future" test when time_t is too limited
  t0006 & t5000: prepare for 64-bit timestamps
  ref-filter: avoid using `unsigned long` for catch-all data type
2017-05-16 11:51:59 +09:00
Junio C Hamano
d97141b0b9 Merge branch 'dt/raise-core-packed-git-limit'
The default packed-git limit value has been raised on larger
platforms to save "git fetch" from a (recoverable) failure while
"gc" is running in parallel.

* dt/raise-core-packed-git-limit:
  Increase core.packedGitLimit
2017-05-16 11:51:49 +09:00
Jeff King
e3f43ce765 usage.c: drop set_error_handle()
The set_error_handle() function was introduced by 3b331e926
(vreportf: report to arbitrary filehandles, 2015-08-11) so
that run-command could send post-fork, pre-exec errors to
the parent's original stderr.

That use went away in 79319b194 (run-command: eliminate
calls to error handling functions in child, 2017-04-19),
which pushes all of the error reporting to the parent.
This leaves no callers of set_error_handle(). As we're not
likely to add any new ones, let's drop it.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-15 13:00:25 +09:00
Jeff King
d8193743e0 usage.c: add BUG() function
There's a convention in Git's code base to write assertions
as:

  if (...some_bad_thing...)
	die("BUG: the terrible thing happened");

with the idea that users should never see a "BUG:" message
(but if they, it at least gives a clue what happened).  We
use die() here because it's convenient, but there are a few
draw-backs:

  1. Without parsing the messages, it's hard for callers to
     distinguish BUG assertions from regular errors.

     For instance, it would be nice if the test suite could
     check that we don't hit any assertions, but
     test_must_fail will pass BUG deaths as OK.

  2. It would be useful to add more debugging features to
     BUG assertions, like file/line numbers or dumping core.

  3. The die() handler can be replaced, and might not
     actually exit the whole program (e.g., it may just
     pthread_exit()). This is convenient for normal errors,
     but for an assertion failure (which is supposed to
     never happen), we're probably better off taking down
     the whole process as quickly and cleanly as possible.

We could address these by checking in die() whether the
error message starts with "BUG", and behaving appropriately.
But there's little advantage at that point to sharing the
die() code, and only downsides (e.g., we can't change the
BUG() interface independently). Moreover, converting all of
the existing BUG calls reveals that the test suite does
indeed trigger a few of them.

Instead, this patch introduces a new BUG() function, which
prints an error before dying via SIGABRT. This gives us test
suite checking and core dumps.  The function is actually a
macro (when supported) so that we can show the file/line
number.

We can convert die("BUG") invocations to BUG() in further
patches, dealing with any test fallouts individually.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-15 11:29:51 +09:00
Johannes Schindelin
28f4aee3fb use uintmax_t for timestamps
Previously, we used `unsigned long` for timestamps. This was only a good
choice on Linux, where we know implicitly that `unsigned long` is what is
used for `time_t`.

However, we want to use a different data type for timestamps for two
reasons:

- there is nothing that says that `unsigned long` should be the same data
  type as `time_t`, and indeed, on 64-bit Windows for example, it is not:
  `unsigned long` is 32-bit but `time_t` is 64-bit.

- even on 32-bit Linux, where `unsigned long` (and thereby `time_t`) is
  32-bit, we *want* to be able to encode timestamps in Git that are
  currently absurdly far in the future, *even if* the system library is
  not able to format those timestamps into date strings.

So let's just switch to the maximal integer type available, which should
be at least 64-bit for all practical purposes these days. It certainly
cannot be worse than `unsigned long`, so...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-27 13:07:40 +09:00
Johannes Schindelin
dddbad728c timestamp_t: a new data type for timestamps
Git's source code assumes that unsigned long is at least as precise as
time_t. Which is incorrect, and causes a lot of problems, in particular
where unsigned long is only 32-bit (notably on Windows, even in 64-bit
versions).

So let's just use a more appropriate data type instead. In preparation
for this, we introduce the new `timestamp_t` data type.

By necessity, this is a very, very large patch, as it has to replace all
timestamps' data type in one go.

As we will use a data type that is not necessarily identical to `time_t`,
we need to be very careful to use `time_t` whenever we interact with the
system functions, and `timestamp_t` everywhere else.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-27 13:07:39 +09:00
Junio C Hamano
5938454cbc Merge branch 'dt/xgethostname-nul-termination'
gethostname(2) may not NUL terminate the buffer if hostname does
not fit; unfortunately there is no easy way to see if our buffer
was too small, but at least this will make sure we will not end up
using garbage past the end of the buffer.

* dt/xgethostname-nul-termination:
  xgethostname: handle long hostnames
  use HOST_NAME_MAX to size buffers for gethostname(2)
2017-04-23 22:07:57 -07:00
Johannes Schindelin
cb71f8bdb5 PRItime: introduce a new "printf format" for timestamps
Currently, Git's source code treats all timestamps as if they were
unsigned longs. Therefore, it is okay to write "%lu" when printing them.

There is a substantial problem with that, though: at least on Windows,
time_t is *larger* than unsigned long, and hence we will want to switch
away from the ill-specified `unsigned long` data type.

So let's introduce the pseudo format "PRItime" (currently simply being
defined to "lu") to make it easier to change the data type used for
timestamps.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-23 20:19:15 -07:00
Johannes Schindelin
1aeb7e756c parse_timestamp(): specify explicitly where we parse timestamps
Currently, Git's source code represents all timestamps as `unsigned
long`. In preparation for using a more appropriate data type, let's
introduce a symbol `parse_timestamp` (currently being defined to
`strtoul`) where appropriate, so that we can later easily switch to,
say, use `strtoull()` instead.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-23 20:19:15 -07:00
David Turner
be4ca29057 Increase core.packedGitLimit
When core.packedGitLimit is exceeded, git will close packs.  If there
is a repack operation going on in parallel with a fetch, the fetch
might open a pack, and then be forced to close it due to
packedGitLimit being hit.  The repack could then delete the pack
out from under the fetch, causing the fetch to fail.

Increase core.packedGitLimit's default value to prevent
this.

On current 64-bit x86_64 machines, 48 bits of address space are
available.  It appears that 64-bit ARM machines have no standard
amount of address space (that is, it varies by manufacturer), and IA64
and POWER machines have the full 64 bits.  So 48 bits is the only
limit that we can reasonably care about.  We reserve a few bits of the
48-bit address space for the kernel's use (this is not strictly
necessary, but it's better to be safe), and use up to the remaining
45.  No git repository will be anywhere near this large any time soon,
so this should prevent the failure.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: David Turner <dturner@twosigma.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-20 22:06:00 -07:00
David Turner
5781a9a270 xgethostname: handle long hostnames
If the full hostname doesn't fit in the buffer supplied to
gethostname, POSIX does not specify whether the buffer will be
null-terminated, so to be safe, we should do it ourselves.  Introduce
new function, xgethostname, which ensures that there is always a \0
at the end of the buffer.

Signed-off-by: David Turner <dturner@twosigma.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-18 19:58:04 -07:00
René Scharfe
da25bdb776 use HOST_NAME_MAX to size buffers for gethostname(2)
POSIX limits the length of host names to HOST_NAME_MAX.  Export the
fallback definition from daemon.c and use this constant to make all
buffers used with gethostname(2) big enough for any possible result
and a terminating NUL.

Inspired-by: David Turner <dturner@twosigma.com>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: David Turner <dturner@twosigma.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-18 19:57:41 -07:00
Junio C Hamano
ba5e05ffef Merge branch 'jk/pack-name-cleanups' into maint
Code clean-up.

* jk/pack-name-cleanups:
  index-pack: make pointer-alias fallbacks safer
  replace snprintf with odb_pack_name()
  odb_pack_keep(): stop generating keepfile name
  sha1_file.c: make pack-name helper globally accessible
  move odb_* declarations out of git-compat-util.h
2017-03-28 13:52:25 -07:00
Junio C Hamano
45cbc37c5f Merge branch 'jk/pack-name-cleanups'
Code clean-up.

* jk/pack-name-cleanups:
  index-pack: make pointer-alias fallbacks safer
  replace snprintf with odb_pack_name()
  odb_pack_keep(): stop generating keepfile name
  sha1_file.c: make pack-name helper globally accessible
  move odb_* declarations out of git-compat-util.h
2017-03-21 15:07:17 -07:00
Jeff King
82c9d6614b move odb_* declarations out of git-compat-util.h
These functions were originally conceived as wrapper
functions similar to xmkstemp(). They were later moved by
463db9b10 (wrapper: move odb_* to environment.c,
2010-11-06). The more appropriate place for a declaration is
in cache.h.

While we're at it, let's add some basic docstrings.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-16 11:04:34 -07:00
Ramsay Jones
b2d593a779 wrapper.c: remove unused gitmkstemps() function
The last call to the mkstemps() function was removed in commit 659488326
("wrapper.c: delete dead function git_mkstemps()", 22-04-2016). In order
to support platforms without mkstemps(), this functionality was provided,
along with a Makefile build variable (NO_MKSTEMPS), by the gitmkstemps()
function. Remove the dead code, along with the defunct build machinery.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-28 11:54:21 -08:00
Junio C Hamano
cbf1860d73 Merge branch 'rs/swap'
Code clean-up.

* rs/swap:
  graph: use SWAP macro
  diff: use SWAP macro
  use SWAP macro
  apply: use SWAP macro
  add SWAP macro
2017-02-15 12:54:19 -08:00
René Scharfe
568edcb95a add SWAP macro
Add a macro for exchanging the values of variables.  It allows users
to avoid repetition and takes care of the temporary variable for them.
It also makes sure that the storage sizes of its two parameters are the
same.  Its memcpy(1) calls are optimized away by current compilers.

Also add a conservative semantic patch for transforming only swaps of
variables of the same type.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-30 14:07:45 -08:00
René Scharfe
3ca8699409 add QSORT_S
Add the macro QSORT_S, a convenient wrapper for qsort_s() that infers
the size of the array elements and dies on error.

Basically all possible errors are programming mistakes (passing NULL as
base of a non-empty array, passing NULL as comparison function,
out-of-bounds accesses), so terminating the program should be acceptable
for most callers.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-23 11:02:36 -08:00
René Scharfe
04ee8b875b compat: add qsort_s()
The function qsort_s() was introduced with C11 Annex K; it provides the
ability to pass a context pointer to the comparison function, supports
the convention of using a NULL pointer for an empty array and performs a
few safety checks.

Add an implementation based on compat/qsort.c for platforms that lack a
native standards-compliant qsort_s() (i.e. basically everyone).  It
doesn't perform the full range of possible checks: It uses size_t
instead of rsize_t and doesn't check nmemb and size against RSIZE_MAX
because we probably don't have the restricted size type defined.  For
the same reason it returns int instead of errno_t.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-23 11:02:34 -08:00
Junio C Hamano
cd1c2e7301 Merge branch 'jk/common-main' into maint-2.10
* jk/common-main:
  common-main: stop munging argv[0] path
  git-compat-util: move content inside ifdef/endif guards
2016-12-05 11:24:28 -08:00
Junio C Hamano
b8171981fd Merge branch 'jk/common-main'
A trivial clean-up to a recently graduated topic.

* jk/common-main:
  git-compat-util: move content inside ifdef/endif guards
2016-10-31 13:15:23 -07:00