time-util: fix using wrong timezone when parsing timestamp #38876
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Previously, an input string ends with short timezone spec e.g. WET, was parsed by setting $TZ environment variable to the timezone. But the timezone might be different from the original local timezone, thus the result might not follow the timezone change in the original local timezone. This makes the check of the short timezone spec with tzname[] earlier, then it is not necessary to load another timezone file for e.g. WET, and provides expected time. This also make it use SAVE_TIMEZONE macro and drop use of forking process. This makes greatly improve performance when parsing string that contains timezone different from the current local timezone. Unfortunately, there is still one corner case that our test fails. When tzdata is built with rearguard enabled, then at least Africa/Windhoek timezone does not provide correct time, but time shifted 1 hour from the original.
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@YHNdnzj Thank you for the review. Addressed comments. PTAL. |
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| if (tmp.return_value == 0 && ret) | ||
| *ret = tmp.usec; | ||
| if (setenv("TZ", strjoina(":", tz), /* overwrite = */ true) < 0) |
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not your fault, but the latest man pages for tzset states:
A nonempty value of TZ can be one of two formats, either of which can be preceded by a colon which is ignored.
hence the prefix should be dropped across the codebase
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Yeah, but I will do that later.
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glibc (and also musl, though we do not officially support it yet) silently ignores colon prefix in $TZ. Let's always not prefix the timezone. tzset(3) states: > A nonempty value of TZ can be one of two formats, either of which can > be preceded by a colon which is ignored. Addresses systemd#38876 (comment).
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glibc (and also musl, though we do not officially support it yet) silently ignores colon prefix in $TZ. Let's always not prefix the timezone. tzset(3) states: > A nonempty value of TZ can be one of two formats, either of which can > be preceded by a colon which is ignored. Addresses systemd#38876 (comment).
yuwata
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Sep 28, 2025
glibc (and also musl, though we do not officially support it yet) silently ignores colon prefix in $TZ. Let's always not prefix the timezone. tzset(3) states: > A nonempty value of TZ can be one of two formats, either of which can > be preceded by a colon which is ignored. Addresses systemd#38876 (comment).
yuwata
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Sep 29, 2025
glibc (and also musl, though we do not officially support it yet) silently ignores colon prefix in $TZ. Let's always not prefix the timezone. tzset(3) states: > A nonempty value of TZ can be one of two formats, either of which can > be preceded by a colon which is ignored. Addresses systemd#38876 (comment).
yuwata
added a commit
to yuwata/systemd
that referenced
this pull request
Sep 29, 2025
glibc (and also musl, though we do not officially support it yet) silently ignores colon prefix in $TZ. Let's always not prefix the timezone. tzset(3) states: > A nonempty value of TZ can be one of two formats, either of which can > be preceded by a colon which is ignored. Addresses systemd#38876 (comment).
yuwata
added a commit
to yuwata/systemd
that referenced
this pull request
Sep 29, 2025
glibc (and also musl, though we do not officially support it yet) silently ignores colon prefix in $TZ. Let's always not prefix the timezone. tzset(3) states: > A nonempty value of TZ can be one of two formats, either of which can > be preceded by a colon which is ignored. Addresses systemd#38876 (comment).
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This mostly fixes issues workarounded several times, e.g. #28472 and #35471.