src/common/time.cpp

   1 /*
   2  * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #include <common/compat/errno.hpp>
   9 #include <common/error.hpp>
  10 #include <common/exception.hpp>
  11 #include <common/macros.hpp>
  12 #include <common/time.hpp>
  13
  14 #include <algorithm>
  15 #include <limits.h>
  16 #include <locale.h>
  17 #include <pthread.h>
  18 #include <stddef.h>
  19 #include <stdint.h>
  20 #include <string.h>
  21
  22 static bool utf8_output_supported;
  23
  24 bool locale_supports_utf8()
  25 {
  26         return utf8_output_supported;
  27 }
  28
  29 int timespec_to_ms(struct timespec ts, unsigned long *ms)
  30 {
  31         unsigned long res, remain_ms;
  32
  33         if (ts.tv_sec > ULONG_MAX / MSEC_PER_SEC) {
  34                 errno = EOVERFLOW;
  35                 return -1; /* multiplication overflow */
  36         }
  37         res = ts.tv_sec * MSEC_PER_SEC;
  38         remain_ms = ULONG_MAX - res;
  39         if (ts.tv_nsec / NSEC_PER_MSEC > remain_ms) {
  40                 errno = EOVERFLOW;
  41                 return -1; /* addition overflow */
  42         }
  43         res += ts.tv_nsec / NSEC_PER_MSEC;
  44         *ms = res;
  45         return 0;
  46 }
  47
  48 struct timespec timespec_abs_diff(struct timespec t1, struct timespec t2)
  49 {
  50         uint64_t ts1 = (uint64_t) t1.tv_sec * (uint64_t) NSEC_PER_SEC + (uint64_t) t1.tv_nsec;
  51         uint64_t ts2 = (uint64_t) t2.tv_sec * (uint64_t) NSEC_PER_SEC + (uint64_t) t2.tv_nsec;
  52         uint64_t diff = std::max(ts1, ts2) - std::min(ts1, ts2);
  53         struct timespec res;
  54
  55         res.tv_sec = diff / (uint64_t) NSEC_PER_SEC;
  56         res.tv_nsec = diff % (uint64_t) NSEC_PER_SEC;
  57         return res;
  58 }
  59
  60 static void __attribute__((constructor)) init_locale_utf8_support()
  61 {
  62         const char *program_locale = setlocale(LC_ALL, nullptr);
  63         const char *lang = getenv("LANG");
  64
  65         if (program_locale && strstr(program_locale, "utf8")) {
  66                 utf8_output_supported = true;
  67         } else if (lang && strstr(lang, "utf8")) {
  68                 utf8_output_supported = true;
  69         }
  70 }
  71
  72 int time_to_iso8601_str(time_t time, char *str, size_t len)
  73 {
  74         int ret = 0;
  75         struct tm *tm_result;
  76         struct tm tm_storage;
  77         size_t strf_ret;
  78
  79         if (len < ISO8601_STR_LEN) {
  80                 ERR("Buffer too short to format ISO 8601 timestamp: %zu bytes provided when at least %zu are needed",
  81                     len,
  82                     ISO8601_STR_LEN);
  83                 ret = -1;
  84                 goto end;
  85         }
  86
  87         tm_result = localtime_r(&time, &tm_storage);
  88         if (!tm_result) {
  89                 ret = -1;
  90                 PERROR("Failed to break down timestamp to tm structure");
  91                 goto end;
  92         }
  93
  94         strf_ret = strftime(str, len, "%Y%m%dT%H%M%S%z", tm_result);
  95         if (strf_ret == 0) {
  96                 ret = -1;
  97                 ERR("Failed to format timestamp as local time");
  98                 goto end;
  99         }
 100 end:
 101         return ret;
 102 }
 103
 104 int time_to_datetime_str(time_t time, char *str, size_t len)
 105 {
 106         int ret = 0;
 107         struct tm *tm_result;
 108         struct tm tm_storage;
 109         size_t strf_ret;
 110
 111         if (len < DATETIME_STR_LEN) {
 112                 ERR("Buffer too short to format to datetime: %zu bytes provided when at least %zu are needed",
 113                     len,
 114                     DATETIME_STR_LEN);
 115                 ret = -1;
 116                 goto end;
 117         }
 118
 119         tm_result = localtime_r(&time, &tm_storage);
 120         if (!tm_result) {
 121                 ret = -1;
 122                 PERROR("Failed to break down timestamp to tm structure");
 123                 goto end;
 124         }
 125
 126         strf_ret = strftime(str, len, "%Y%m%d-%H%M%S", tm_result);
 127         if (strf_ret == 0) {
 128                 ret = -1;
 129                 ERR("Failed to format timestamp as local time");
 130                 goto end;
 131         }
 132 end:
 133         return ret;
 134 }
 135
 136 std::string lttng::utils::time_to_iso8601_str(std::time_t time)
 137 {
 138         std::string iso8601_str(ISO8601_STR_LEN, '\0');
 139         const auto ret = ::time_to_iso8601_str(time, &iso8601_str[0], iso8601_str.capacity());
 140
 141         if (ret) {
 142                 LTTNG_THROW_ERROR("Failed to format time to iso8601 format");
 143         }
 144
 145         /* Don't include '\0' in the C++ string. */
 146         iso8601_str.resize(iso8601_str.size() - 1);
 147
 148         return iso8601_str;
 149 }