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>
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>
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>
Git's source code refers to timestamps as unsigned long, which is
ill-defined, as there is no guarantee about the number of bits that
data type has.
In preparation of switching to another data type that is large enough
to hold "far in the future" dates, we need to prepare the t0006-date.sh
script for the case where we *still* cannot format those dates if the
system library uses 32-bit time_t.
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git's source code refers to timestamps as unsigned longs. On 32-bit
platforms, as well as on Windows, unsigned long is not large enough to
capture dates that are "absurdly far in the future".
It is perfectly valid by the C standard, of course, for the `long` data
type to refer to 32-bit integers. That is why the `time_t` data type
exists: so that it can be 64-bit even if `long` is 32-bit. Git's source
code simply uses an incorrect data type for timestamps, is all.
The earlier quick fix 6b9c38e14c (t0006: skip "far in the future" test
when unsigned long is not long enough, 2016-07-11) papered over this
issue simply by skipping the respective test cases on platforms where
they would fail due to the data type in use.
This quick fix, however, tests for *long* to be 64-bit or not. What we
need, though, is a test that says whether *whatever data type we use for
timestamps* is 64-bit or not.
The same quick fix was used to handle the similar problem where Git's
source code uses `unsigned long` to represent size, instead of `size_t`,
conflating the two issues.
So let's just add another prerequisite to test specifically whether
timestamps are represented by a 64-bit data type or not. Later, after we
switch to a larger data type, we can flip that prerequisite to test
`time_t` instead of `long`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are certain house-keeping tasks that need to be performed at
the very beginning of any Git program, and programs that are not
built-in commands had to do them exactly the same way as "git"
potty does. It was easy to make mistakes in one-off standalone
programs (like test helpers). A common "main()" function that
calls cmd_main() of individual program has been introduced to
make it harder to make mistakes.
* jk/common-main:
mingw: declare main()'s argv as const
common-main: call git_setup_gettext()
common-main: call restore_sigpipe_to_default()
common-main: call sanitize_stdfds()
common-main: call git_extract_argv0_path()
add an extra level of indirection to main()
The internal code used to show local timezone offset is not
prepared to handle timestamps beyond year 2100, and gave a
bogus offset value to the caller. Use a more benign looking
+0000 instead and let "git log" going in such a case, instead
of aborting.
* jk/tzoffset-fix:
local_tzoffset: detect errors from tm_to_time_t
t0006: test various date formats
t0006: rename test-date's "show" to "relative"
This keeps top dir a bit less crowded. And because these programs are
for testing purposes, it makes sense that they stay somewhere in t/
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
