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(void)
  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 +
  51                         (uint64_t) t1.tv_nsec;
  52         uint64_t ts2 = (uint64_t) t2.tv_sec * (uint64_t) NSEC_PER_SEC +
  53                         (uint64_t) t2.tv_nsec;
  54         uint64_t diff = std::max(ts1, ts2) - std::min(ts1, ts2);
  55         struct timespec res;
  56
  57         res.tv_sec = diff / (uint64_t) NSEC_PER_SEC;
  58         res.tv_nsec = diff % (uint64_t) NSEC_PER_SEC;
  59         return res;
  60 }
  61
  62 static
  63 void __attribute__((constructor)) init_locale_utf8_support(void)
  64 {
  65         const char *program_locale = setlocale(LC_ALL, NULL);
  66         const char *lang = getenv("LANG");
  67
  68         if (program_locale && strstr(program_locale, "utf8")) {
  69                 utf8_output_supported = true;
  70         } else if (lang && strstr(lang, "utf8")) {
  71                 utf8_output_supported = true;
  72         }
  73 }
  74
  75 int time_to_iso8601_str(time_t time, char *str, size_t len)
  76 {
  77         int ret = 0;
  78         struct tm *tm_result;
  79         struct tm tm_storage;
  80         size_t strf_ret;
  81
  82         if (len < ISO8601_STR_LEN) {
  83                 ERR("Buffer too short to format ISO 8601 timestamp: %zu bytes provided when at least %zu are needed",
  84                                 len, ISO8601_STR_LEN);
  85                 ret = -1;
  86                 goto end;
  87         }
  88
  89         tm_result = localtime_r(&time, &tm_storage);
  90         if (!tm_result) {
  91                 ret = -1;
  92                 PERROR("Failed to break down timestamp to tm structure");
  93                 goto end;
  94         }
  95
  96         strf_ret = strftime(str, len, "%Y%m%dT%H%M%S%z", tm_result);
  97         if (strf_ret == 0) {
  98                 ret = -1;
  99                 ERR("Failed to format timestamp as local time");
 100                 goto end;
 101         }
 102 end:
 103         return ret;
 104 }
 105
 106 int time_to_datetime_str(time_t time, char *str, size_t len)
 107 {
 108         int ret = 0;
 109         struct tm *tm_result;
 110         struct tm tm_storage;
 111         size_t strf_ret;
 112
 113         if (len < DATETIME_STR_LEN) {
 114                 ERR("Buffer too short to format to datetime: %zu bytes provided when at least %zu are needed",
 115                                 len, DATETIME_STR_LEN);
 116                 ret = -1;
 117                 goto end;
 118         }
 119
 120         tm_result = localtime_r(&time, &tm_storage);
 121         if (!tm_result) {
 122                 ret = -1;
 123                 PERROR("Failed to break down timestamp to tm structure");
 124                 goto end;
 125         }
 126
 127         strf_ret = strftime(str, len, "%Y%m%d-%H%M%S", tm_result);
 128         if (strf_ret == 0) {
 129                 ret = -1;
 130                 ERR("Failed to format timestamp as local time");
 131                 goto end;
 132         }
 133 end:
 134         return ret;
 135 }
 136
 137 std::string lttng::utils::time_to_iso8601_str(std::time_t time)
 138 {
 139         std::string iso8601_str(ISO8601_STR_LEN, '\0');
 140         const auto ret = ::time_to_iso8601_str(time, &iso8601_str[0], iso8601_str.capacity());
 141
 142         if (ret) {
 143                 LTTNG_THROW_ERROR("Failed to format time to iso8601 format");
 144         }
 145
 146         /* Don't include '\0' in the C++ string. */
 147         iso8601_str.resize(iso8601_str.size() - 1);
 148
 149         return iso8601_str;
 150 }