common: compile libcommon as C++

[lttng-tools.git] / src / common / time.cpp

diff --git a/src/common/time.cpp b/src/common/time.cpp
new file mode 100644 (file)
index 0000000..a08358f
--- /dev/null
+++ b/src/common/time.cpp
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#include <common/time.h>
+#include <common/error.h>
+#include <common/macros.h>
+#include <common/error.h>
+#include <common/compat/errno.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <limits.h>
+#include <pthread.h>
+#include <locale.h>
+#include <string.h>
+#include <algorithm>
+
+static bool utf8_output_supported;
+
+bool locale_supports_utf8(void)
+{
+       return utf8_output_supported;
+}
+
+int timespec_to_ms(struct timespec ts, unsigned long *ms)
+{
+       unsigned long res, remain_ms;
+
+       if (ts.tv_sec > ULONG_MAX / MSEC_PER_SEC) {
+               errno = EOVERFLOW;
+               return -1;      /* multiplication overflow */
+       }
+       res = ts.tv_sec * MSEC_PER_SEC;
+       remain_ms = ULONG_MAX - res;
+       if (ts.tv_nsec / NSEC_PER_MSEC > remain_ms) {
+               errno = EOVERFLOW;
+               return -1;      /* addition overflow */
+       }
+       res += ts.tv_nsec / NSEC_PER_MSEC;
+       *ms = res;
+       return 0;
+}
+
+struct timespec timespec_abs_diff(struct timespec t1, struct timespec t2)
+{
+       uint64_t ts1 = (uint64_t) t1.tv_sec * (uint64_t) NSEC_PER_SEC +
+                       (uint64_t) t1.tv_nsec;
+       uint64_t ts2 = (uint64_t) t2.tv_sec * (uint64_t) NSEC_PER_SEC +
+                       (uint64_t) t2.tv_nsec;
+       uint64_t diff = std::max(ts1, ts2) - std::min(ts1, ts2);
+       struct timespec res;
+
+       res.tv_sec = diff / (uint64_t) NSEC_PER_SEC;
+       res.tv_nsec = diff % (uint64_t) NSEC_PER_SEC;
+       return res;
+}
+
+static
+void __attribute__((constructor)) init_locale_utf8_support(void)
+{
+       const char *program_locale = setlocale(LC_ALL, NULL);
+       const char *lang = getenv("LANG");
+
+       if (program_locale && strstr(program_locale, "utf8")) {
+               utf8_output_supported = true;
+       } else if (lang && strstr(lang, "utf8")) {
+               utf8_output_supported = true;
+       }
+}
+
+int time_to_iso8601_str(time_t time, char *str, size_t len)
+{
+       int ret = 0;
+       struct tm *tm_result;
+       struct tm tm_storage;
+       size_t strf_ret;
+
+       if (len < ISO8601_STR_LEN) {
+               ERR("Buffer too short to format ISO 8601 timestamp: %zu bytes provided when at least %zu are needed",
+                               len, ISO8601_STR_LEN);
+               ret = -1;
+               goto end;
+       }
+
+       tm_result = localtime_r(&time, &tm_storage);
+       if (!tm_result) {
+               ret = -1;
+               PERROR("Failed to break down timestamp to tm structure");
+               goto end;
+       }
+
+       strf_ret = strftime(str, len, "%Y%m%dT%H%M%S%z", tm_result);
+       if (strf_ret == 0) {
+               ret = -1;
+               ERR("Failed to format timestamp as local time");
+               goto end;
+       }
+end:
+       return ret;
+}
+
+int time_to_datetime_str(time_t time, char *str, size_t len)
+{
+       int ret = 0;
+       struct tm *tm_result;
+       struct tm tm_storage;
+       size_t strf_ret;
+
+       if (len < DATETIME_STR_LEN) {
+               ERR("Buffer too short to format to datetime: %zu bytes provided when at least %zu are needed",
+                               len, DATETIME_STR_LEN);
+               ret = -1;
+               goto end;
+       }
+
+       tm_result = localtime_r(&time, &tm_storage);
+       if (!tm_result) {
+               ret = -1;
+               PERROR("Failed to break down timestamp to tm structure");
+               goto end;
+       }
+
+       strf_ret = strftime(str, len, "%Y%m%d-%H%M%S", tm_result);
+       if (strf_ret == 0) {
+               ret = -1;
+               ERR("Failed to format timestamp as local time");
+               goto end;
+       }
+end:
+       return ret;
+}