From 327d9d482fd4480ca16e993fe2699c8bbc166251 Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Wed, 24 Jul 2024 17:21:12 +0200 Subject: log, util: Fix sub-second part in relative log time calculation For some reason, in commit 01efc71ddd25 ("log, conf: Add support for logging to file"), I added calculations for relative logging timestamps using the difference for the seconds part only, not for accounting for the fractional part. Fix that by storing the initial timestamp, log_start, as a timespec struct, and by calculating the difference from the starting time. Do this in a macro as we need the same format in a few places. To calculate the difference, turn the existing timespec_diff_ms() to microseconds, timespec_diff_us(), and rewrite timespec_diff_ms() to use that. Signed-off-by: Stefano Brivio Reviewed-by: David Gibson --- log.c | 42 ++++++++++++++++++++++-------------------- 1 file changed, 22 insertions(+), 20 deletions(-) (limited to 'log.c') diff --git a/log.c b/log.c index 54483e7..32157a8 100644 --- a/log.c +++ b/log.c @@ -40,12 +40,21 @@ static size_t log_written; /* Currently used bytes in log file */ static size_t log_cut_size; /* Bytes to cut at start on rotation */ static char log_header[BUFSIZ]; /* File header, written back on cuts */ -static time_t log_start; /* Start timestamp */ +static struct timespec log_start; /* Start timestamp */ int log_trace; /* --trace mode enabled */ bool log_conf_parsed; /* Logging options already parsed */ bool log_runtime; /* Daemonised, or ready in foreground */ +/** + * logtime_fmt_and_arg() - Build format and arguments to print relative log time + * @x: Current timestamp + */ +#define logtime_fmt_and_arg(x) \ + "%lli.%04lli", \ + (timespec_diff_us((x), &log_start) / 1000000LL), \ + (timespec_diff_us((x), &log_start) / 100LL) + /** * vlogmsg() - Print or send messages to log or output files as configured * @newline: Append newline at the end of the message, if missing @@ -60,9 +69,8 @@ void vlogmsg(bool newline, int pri, const char *format, va_list ap) if (debug_print) { clock_gettime(CLOCK_REALTIME, &tp); - fprintf(stderr, "%lli.%04lli: ", - (long long int)tp.tv_sec - log_start, - (long long int)tp.tv_nsec / (100L * 1000)); + fprintf(stderr, logtime_fmt_and_arg(&tp)); + fprintf(stderr, ": "); } if ((log_mask & LOG_MASK(LOG_PRI(pri))) || !log_conf_parsed) { @@ -144,12 +152,9 @@ void trace_init(int enable) */ void __openlog(const char *ident, int option, int facility) { - struct timespec tp; - (void)option; - clock_gettime(CLOCK_REALTIME, &tp); - log_start = tp.tv_sec; + clock_gettime(CLOCK_REALTIME, &log_start); if (log_sock < 0) { struct sockaddr_un a = { .sun_family = AF_UNIX, }; @@ -255,10 +260,8 @@ static void logfile_rotate_fallocate(int fd, const struct timespec *now) if (read(fd, buf, BUFSIZ) == -1) return; - n = snprintf(buf, BUFSIZ, - "%s - log truncated at %lli.%04lli", log_header, - (long long int)(now->tv_sec - log_start), - (long long int)(now->tv_nsec / (100L * 1000))); + n = snprintf(buf, BUFSIZ, "%s - log truncated at ", log_header); + n += snprintf(buf + n, BUFSIZ - n, logtime_fmt_and_arg(now)); /* Avoid partial lines by padding the header with spaces */ nl = memchr(buf + n + 1, '\n', BUFSIZ - n - 1); @@ -288,10 +291,11 @@ static void logfile_rotate_move(int fd, const struct timespec *now) char buf[BUFSIZ]; const char *nl; - header_len = snprintf(buf, BUFSIZ, - "%s - log truncated at %lli.%04lli\n", log_header, - (long long int)(now->tv_sec - log_start), - (long long int)(now->tv_nsec / (100L * 1000))); + header_len = snprintf(buf, BUFSIZ, "%s - log truncated at ", + log_header); + header_len += snprintf(buf + header_len, BUFSIZ - header_len, + logtime_fmt_and_arg(now)); + if (lseek(fd, 0, SEEK_SET) == -1) return; if (write(fd, buf, header_len) == -1) @@ -383,10 +387,8 @@ void logfile_write(bool newline, int pri, const char *format, va_list ap) if (clock_gettime(CLOCK_REALTIME, &now)) return; - n = snprintf(buf, BUFSIZ, "%lli.%04lli: %s", - (long long int)(now.tv_sec - log_start), - (long long int)(now.tv_nsec / (100L * 1000)), - logfile_prefix[pri]); + n = snprintf(buf, BUFSIZ, logtime_fmt_and_arg(&now)); + n += snprintf(buf + n, BUFSIZ - n, ": %s", logfile_prefix[pri]); n += vsnprintf(buf + n, BUFSIZ - n, format, ap); -- cgit v1.2.3