git/date.c, branch v2.20.2

approxidate: fix NULL dereference in date_time()

2018-11-07T02:04:06Z

When we see a time like "noon", we pass "12" to our date_time() helper, which sets the hour to 12pm. If the current time is before noon, then we wrap around to yesterday using date_yesterday(). But unlike the normal calls to date_yesterday() from approxidate_alpha(), we pass a NULL "num" parameter. Since c27cc94fad (approxidate: handle pending number for "specials", 2018-11-02), that causes a segfault. One way to fix this is by checking for NULL. But arguably date_time() is abusing our helper by passing NULL in the first place (and this is the only case where one of these "special" parsers is used this way). So instead, let's have it just do the 1-day subtraction itself. It's still just a one-liner due to our update_tm() helper. Note that the test added here is a little funny, as we say "10am noon", which makes the "10am" seem pointless. But this bug can only be triggered when it the currently-parsed hour is before the special time. The latest special time is "tea" at 1700, but t0006 uses a hard-coded TEST_DATE_NOW of 1900. We could reset TEST_DATE_NOW, but that may lead to confusion in other tests. Just saying "10am noon" makes this test self-contained. Reported-by: Carlo Arenas Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

approxidate: handle pending number for "specials"

2018-11-02T11:49:53Z

The approxidate parser has a table of special keywords like "yesterday", "noon", "pm", etc. Some of these, like "pm", do the right thing if we've recently seen a number: "3pm" is what you'd think. However, most of them do not look at or modify the pending-number flag at all, which means a number may "jump" across a significant keyword and be used unexpectedly. For example, when parsing: January 5th noon pm we'd connect the "5" to "pm", and ignore it as a day-of-month. This is obviously a bit silly, as "noon" already implies "pm". And other mis-parsed things are generally as silly ("January 5th noon, years ago" would connect the 5 to "years", but probably nobody would type that). However, the fix is simple: when we see a keyword like "noon", we should flush the pending number (as we would if we hit another number, or the end of the string). In a few of the specials that actually modify the day, we can simply throw away the number (saying "Jan 5 yesterday" should not respect the number at all). Note that we have to either move or forward-declare the static pending_number() to make it accessible to these functions; this patch moves it. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Replace all die("BUG: ...") calls by BUG() ones

2018-05-06T10:06:13Z

In d8193743e08 (usage.c: add BUG() function, 2017-05-12), a new macro was introduced to use for reporting bugs instead of die(). It was then subsequently used to convert one single caller in 588a538ae55 (setup_git_env: convert die("BUG") to BUG(), 2017-05-12). The cover letter of the patch series containing this patch (cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not terribly clear why only one call site was converted, or what the plan is for other, similar calls to die() to report bugs. Let's just convert all remaining ones in one fell swoop. This trick was performed by this invocation: sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c) Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

Merge branch 'ab/strbuf-addftime-tzname-boolify'

2017-07-07T01:14:47Z

strbuf_addftime() is further getting tweaked. * ab/strbuf-addftime-tzname-boolify: strbuf: change an always NULL/"" strbuf_addftime() param to bool strbuf.h comment: discuss strbuf_addftime() arguments in order

strbuf: change an always NULL/"" strbuf_addftime() param to bool

2017-07-01T17:47:05Z

strbuf_addftime() allows callers to pass a time zone name for expanding %Z. The only current caller either passes the empty string or NULL, in which case %Z is handed over verbatim to strftime(3). Replace that string parameter with a flag controlling whether to remove %Z from the format specification. This simplifies the code. Commit-message-by: René Scharfe Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

Merge branch 'rs/strbuf-addftime-zZ'

2017-06-22T21:15:25Z

As there is no portable way to pass timezone information to strftime, some output format from "git log" and friends are impossible to produce. Teach our own strbuf_addftime to replace %z and %Z with caller-supplied values to help working around this. * rs/strbuf-addftime-zZ: date: use localtime() for "-local" time formats t0006: check --date=format zone offsets strbuf: let strbuf_addftime handle %z and %Z itself

date: use localtime() for "-local" time formats

2017-06-15T21:39:15Z

When we convert seconds-since-epochs timestamps into a broken-down "struct tm", we do so by adjusting the timestamp according to the known offset and then using gmtime() to break down the result. This means that the resulting struct "knows" that it's in GMT, even though the time it represents is adjusted for a different zone. The fields where it stores this data are not portably accessible, so we have no way to override them to tell them the real zone info. For the most part, this works. Our date-formatting routines don't pay attention to these inaccessible fields, and use the same tz info we provided for adjustment. The one exception is when we call strftime(), whose %Z format reveals this hidden timezone data. We solved that by always showing the empty string for %Z. This is allowed by POSIX, but not very helpful to the user. We can't make this work in the general case, as there's no portable function for setting an arbitrary timezone (and anyway, we don't have the zone name for the author zones, only their offsets). But for the special case of the "-local" formats, we can just skip the adjustment and use localtime() instead of gmtime(). This makes --date=format-local:%Z work correctly, showing the local timezone instead of an empty string. The new test checks the result for "UTC", our default test-lib value for $TZ. Using something like EST5 might be more interesting, but the actual zone string is system-dependent (for instance, on my system it expands to just EST). Hopefully "UTC" is vanilla enough that every system treats it the same. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

strbuf: let strbuf_addftime handle %z and %Z itself

2017-06-15T21:34:37Z

There is no portable way to pass timezone information to strftime. Add parameters for timezone offset and name to strbuf_addftime and let it handle the timezone-related format specifiers %z and %Z internally. Callers can opt out for %Z by passing NULL as timezone name. %z is always handled internally -- this helps on Windows, where strftime would expand it to a timezone name (same as %Z), in violation of POSIX. Modifiers are not handled, e.g. %Ez is still passed to strftime. Use an empty string as timezone name in show_date (the only current caller) for now because we only have the timezone offset in non-local mode. POSIX allows %Z to resolve to an empty string in case of missing information. Helped-by: Ulrich Mueller Helped-by: Jeff King Signed-off-by: Rene Scharfe Signed-off-by: Junio C Hamano

date.c: abort if the system time cannot handle one of our timestamps

2017-04-27T04:07:40Z

We are about to switch to a new data type for time stamps that is definitely not smaller or equal, but larger or equal to time_t. So before using the system functions to process or format timestamps, let's make extra certain that they can handle what we feed them. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

timestamp_t: a new data type for timestamps

2017-04-27T04:07:39Z

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 Signed-off-by: Junio C Hamano