From c3fbf81a8534cf88ff948d12004eb94929ec1174 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ren=C3=A9=20Scharfe?= Date: Thu, 15 Jun 2017 14:29:53 +0200 Subject: [PATCH] strbuf: let strbuf_addftime handle %z and %Z itself 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 --- Documentation/rev-list-options.txt | 3 ++- date.c | 2 +- strbuf.c | 41 +++++++++++++++++++++++++++--- strbuf.h | 10 ++++++-- t/t0006-date.sh | 6 +++++ 5 files changed, 54 insertions(+), 8 deletions(-) diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index a02f7324c0..3921066b7f 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -764,7 +764,8 @@ timezone value. 1970). As with `--raw`, this is always in UTC and therefore `-local` has no effect. + -`--date=format:...` feeds the format `...` to your system `strftime`. +`--date=format:...` feeds the format `...` to your system `strftime`, +except for %z and %Z, which are handled internally. Use `--date=format:%c` to show the date in your system locale's preferred format. See the `strftime` manual for a complete list of format placeholders. When using `-local`, the correct syntax is diff --git a/date.c b/date.c index a996331f5b..6eccbd8546 100644 --- a/date.c +++ b/date.c @@ -233,7 +233,7 @@ const char *show_date(unsigned long time, int tz, const struct date_mode *mode) month_names[tm->tm_mon], tm->tm_year + 1900, tm->tm_hour, tm->tm_min, tm->tm_sec, tz); else if (mode->type == DATE_STRFTIME) - strbuf_addftime(&timebuf, mode->strftime_fmt, tm); + strbuf_addftime(&timebuf, mode->strftime_fmt, tm, tz, ""); else strbuf_addf(&timebuf, "%.3s %.3s %d %02d:%02d:%02d %d%c%+05d", weekday_names[tm->tm_wday], diff --git a/strbuf.c b/strbuf.c index 00457940cf..be3b9e37b1 100644 --- a/strbuf.c +++ b/strbuf.c @@ -785,14 +785,48 @@ char *xstrfmt(const char *fmt, ...) return ret; } -void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm) +void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm, + int tz_offset, const char *tz_name) { + struct strbuf munged_fmt = STRBUF_INIT; size_t hint = 128; size_t len; if (!*fmt) return; + /* + * There is no portable way to pass timezone information to + * strftime, so we handle %z and %Z here. + */ + for (;;) { + const char *percent = strchrnul(fmt, '%'); + strbuf_add(&munged_fmt, fmt, percent - fmt); + if (!*percent) + break; + fmt = percent + 1; + switch (*fmt) { + case '%': + strbuf_addstr(&munged_fmt, "%%"); + fmt++; + break; + case 'z': + strbuf_addf(&munged_fmt, "%+05d", tz_offset); + fmt++; + break; + case 'Z': + if (tz_name) { + strbuf_addstr(&munged_fmt, tz_name); + fmt++; + break; + } + /* FALLTHROUGH */ + default: + strbuf_addch(&munged_fmt, '%'); + } + } + fmt = munged_fmt.buf; + strbuf_grow(sb, hint); len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm); @@ -804,17 +838,16 @@ void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm) * output contains at least one character, and then drop the extra * character before returning. */ - struct strbuf munged_fmt = STRBUF_INIT; - strbuf_addf(&munged_fmt, "%s ", fmt); + strbuf_addch(&munged_fmt, ' '); while (!len) { hint *= 2; strbuf_grow(sb, hint); len = strftime(sb->buf + sb->len, sb->alloc - sb->len, munged_fmt.buf, tm); } - strbuf_release(&munged_fmt); len--; /* drop munged space */ } + strbuf_release(&munged_fmt); strbuf_setlen(sb, sb->len + len); } diff --git a/strbuf.h b/strbuf.h index 80047b1bb7..4559035c47 100644 --- a/strbuf.h +++ b/strbuf.h @@ -340,8 +340,14 @@ extern void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap); /** * Add the time specified by `tm`, as formatted by `strftime`. - */ -extern void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm); + * `tz_name` is used to expand %Z internally unless it's NULL. + * `tz_offset` is in decimal hhmm format, e.g. -600 means six hours west + * of Greenwich, and it's used to expand %z internally. However, tokens + * with modifiers (e.g. %Ez) are passed to `strftime`. + */ +extern void strbuf_addftime(struct strbuf *sb, const char *fmt, + const struct tm *tm, int tz_offset, + const char *tz_name); /** * Read a given size of data from a FILE* pointer to the buffer. diff --git a/t/t0006-date.sh b/t/t0006-date.sh index c0c910867d..fded9dbd68 100755 --- a/t/t0006-date.sh +++ b/t/t0006-date.sh @@ -51,6 +51,12 @@ check_show iso-local "$TIME" '2016-06-15 14:13:20 +0000' check_show raw-local "$TIME" '1466000000 +0000' check_show unix-local "$TIME" '1466000000' +check_show 'format:%z' "$TIME" '+0200' +check_show 'format-local:%z' "$TIME" '+0000' +check_show 'format:%Z' "$TIME" '' +check_show 'format:%%z' "$TIME" '%z' +check_show 'format-local:%%z' "$TIME" '%z' + # arbitrary time absurdly far in the future FUTURE="5758122296 -0400" check_show iso "$FUTURE" "2152-06-19 18:24:56 -0400" LONG_IS_64BIT -- 2.39.2