diff options
Diffstat (limited to 'src/basic/time-util.c')
| -rw-r--r-- | src/basic/time-util.c | 146 |
1 files changed, 123 insertions, 23 deletions
diff --git a/src/basic/time-util.c b/src/basic/time-util.c index 24e681bf85..0ef1f6393e 100644 --- a/src/basic/time-util.c +++ b/src/basic/time-util.c @@ -254,32 +254,95 @@ struct timeval *timeval_store(struct timeval *tv, usec_t u) { return tv; } -static char *format_timestamp_internal(char *buf, size_t l, usec_t t, - bool utc, bool us) { +static char *format_timestamp_internal( + char *buf, + size_t l, + usec_t t, + bool utc, + bool us) { + + /* The weekdays in non-localized (English) form. We use this instead of the localized form, so that our + * generated timestamps may be parsed with parse_timestamp(), and always read the same. */ + static const char * const weekdays[] = { + [0] = "Sun", + [1] = "Mon", + [2] = "Tue", + [3] = "Wed", + [4] = "Thu", + [5] = "Fri", + [6] = "Sat", + }; + struct tm tm; time_t sec; - int k; + size_t n; assert(buf); - assert(l > 0); + if (l < + 3 + /* week day */ + 1 + 10 + /* space and date */ + 1 + 8 + /* space and time */ + (us ? 1 + 6 : 0) + /* "." and microsecond part */ + 1 + 1 + /* space and shortest possible zone */ + 1) + return NULL; /* Not enough space even for the shortest form. */ if (t <= 0 || t == USEC_INFINITY) + return NULL; /* Timestamp is unset */ + + sec = (time_t) (t / USEC_PER_SEC); /* Round down */ + if ((usec_t) sec != (t / USEC_PER_SEC)) + return NULL; /* overflow? */ + + if (!localtime_or_gmtime_r(&sec, &tm, utc)) return NULL; - sec = (time_t) (t / USEC_PER_SEC); - localtime_or_gmtime_r(&sec, &tm, utc); + /* Start with the week day */ + assert((size_t) tm.tm_wday < ELEMENTSOF(weekdays)); + memcpy(buf, weekdays[tm.tm_wday], 4); - if (us) - k = strftime(buf, l, "%a %Y-%m-%d %H:%M:%S", &tm); - else - k = strftime(buf, l, "%a %Y-%m-%d %H:%M:%S %Z", &tm); + /* Add the main components */ + if (strftime(buf + 3, l - 3, " %Y-%m-%d %H:%M:%S", &tm) <= 0) + return NULL; /* Doesn't fit */ - if (k <= 0) - return NULL; + /* Append the microseconds part, if that's requested */ if (us) { - snprintf(buf + strlen(buf), l - strlen(buf), ".%06llu", (unsigned long long) (t % USEC_PER_SEC)); - if (strftime(buf + strlen(buf), l - strlen(buf), " %Z", &tm) <= 0) - return NULL; + n = strlen(buf); + if (n + 8 > l) + return NULL; /* Microseconds part doesn't fit. */ + + sprintf(buf + n, ".%06llu", (unsigned long long) (t % USEC_PER_SEC)); + } + + /* Append the timezone */ + n = strlen(buf); + if (utc) { + /* If this is UTC then let's explicitly use the "UTC" string here, because gmtime_r() normally uses the + * obsolete "GMT" instead. */ + if (n + 5 > l) + return NULL; /* "UTC" doesn't fit. */ + + strcpy(buf + n, " UTC"); + + } else if (!isempty(tm.tm_zone)) { + size_t tn; + + /* An explicit timezone is specified, let's use it, if it fits */ + tn = strlen(tm.tm_zone); + if (n + 1 + tn + 1 > l) { + /* The full time zone does not fit in. Yuck. */ + + if (n + 1 + _POSIX_TZNAME_MAX + 1 > l) + return NULL; /* Not even enough space for the POSIX minimum (of 6)? In that case, complain that it doesn't fit */ + + /* So the time zone doesn't fit in fully, but the caller passed enough space for the POSIX + * minimum time zone length. In this case suppress the timezone entirely, in order not to dump + * an overly long, hard to read string on the user. This should be safe, because the user will + * assume the local timezone anyway if none is shown. And so does parse_timestamp(). */ + } else { + buf[n++] = ' '; + strcpy(buf + n, tm.tm_zone); + } } return buf; @@ -539,12 +602,11 @@ int parse_timestamp(const char *t, usec_t *usec) { { "Sat", 6 }, }; - const char *k; - const char *utc; + const char *k, *utc, *tzn = NULL; struct tm tm, copy; time_t x; usec_t x_usec, plus = 0, minus = 0, ret; - int r, weekday = -1; + int r, weekday = -1, dst = -1; unsigned i; /* @@ -609,15 +671,55 @@ int parse_timestamp(const char *t, usec_t *usec) { goto finish; } + /* See if the timestamp is suffixed with UTC */ utc = endswith_no_case(t, " UTC"); if (utc) t = strndupa(t, utc - t); + else { + const char *e = NULL; + int j; + + tzset(); + + /* See if the timestamp is suffixed by either the DST or non-DST local timezone. Note that we only + * support the local timezones here, nothing else. Not because we wouldn't want to, but simply because + * there are no nice APIs available to cover this. By accepting the local time zone strings, we make + * sure that all timestamps written by format_timestamp() can be parsed correctly, even though we don't + * support arbitrary timezone specifications. */ + + for (j = 0; j <= 1; j++) { + + if (isempty(tzname[j])) + continue; + + e = endswith_no_case(t, tzname[j]); + if (!e) + continue; + if (e == t) + continue; + if (e[-1] != ' ') + continue; + + break; + } - x = ret / USEC_PER_SEC; + if (IN_SET(j, 0, 1)) { + /* Found one of the two timezones specified. */ + t = strndupa(t, e - t - 1); + dst = j; + tzn = tzname[j]; + } + } + + x = (time_t) (ret / USEC_PER_SEC); x_usec = 0; - assert_se(localtime_or_gmtime_r(&x, &tm, utc)); - tm.tm_isdst = -1; + if (!localtime_or_gmtime_r(&x, &tm, utc)) + return -EINVAL; + + tm.tm_isdst = dst; + if (tzn) + tm.tm_zone = tzn; if (streq(t, "today")) { tm.tm_sec = tm.tm_min = tm.tm_hour = 0; @@ -634,7 +736,6 @@ int parse_timestamp(const char *t, usec_t *usec) { goto from_tm; } - for (i = 0; i < ELEMENTSOF(day_nr); i++) { size_t skip; @@ -727,7 +828,6 @@ parse_usec: return -EINVAL; x_usec = add; - } from_tm: |