projects / lttngtop.git / blame
| Commit | Line | Data |
|---|---|---|
| b1acd2b3 JD |
1 | #ifndef _BABELTRACE_UTC_H |
| 2 | #define _BABELTRACE_UTC_H | |
| 3 | ||
| 4 | /* | |
| 5 | * Copyright (C) 2011-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 6 | * | |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
| 8 | * of this software and associated documentation files (the "Software"), to deal | |
| 9 | * in the Software without restriction, including without limitation the rights | |
| 10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
| 11 | * copies of the Software, and to permit persons to whom the Software is | |
| 12 | * furnished to do so, subject to the following conditions: | |
| 13 | * | |
| 14 | * The above copyright notice and this permission notice shall be included in | |
| 15 | * all copies or substantial portions of the Software. | |
| 16 | * | |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
| 20 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
| 21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
| 22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | |
| 23 | * SOFTWARE. | |
| 24 | */ | |
| 25 | ||
| 26 | #include <time.h> | |
| 27 | ||
| 28 | /* If set, use GNU or BSD timegm(3) */ | |
| 29 | #if defined(_BSD_SOURCE) || defined(_SVID_SOURCE) | |
| 30 | ||
| 31 | static inline | |
| 32 | time_t babeltrace_timegm(struct tm *tm) | |
| 33 | { | |
| 34 | return timegm(tm); | |
| 35 | } | |
| 36 | ||
| 37 | #else | |
| 38 | ||
| 39 | #include <string.h> | |
| 40 | #include <stdlib.h> | |
| 41 | ||
| 42 | /* | |
| 43 | * Note: Below implementation of timegm() is not thread safe | |
| 44 | * as it changes the environment | |
| 45 | * variable TZ. It is OK as long as it is kept in self-contained program, | |
| 46 | * but should not be used within thread-safe library code. | |
| 47 | */ | |
| 48 | ||
| 49 | static inline | |
| 50 | time_t babeltrace_timegm(struct tm *tm) | |
| 51 | { | |
| 52 | time_t ret; | |
| 53 | char *tz; | |
| 54 | ||
| 55 | tz = getenv("TZ"); | |
| 56 | /* | |
| 57 | * Make a temporary copy, as the environment variable will be | |
| 58 | * modified. | |
| 59 | */ | |
| 60 | if (tz) { | |
| 61 | tz = strdup(tz); | |
| 62 | if (!tz) { | |
| 63 | /* | |
| 64 | * Memory allocation error. | |
| 65 | */ | |
| 66 | return (time_t) -1; | |
| 67 | } | |
| 68 | } | |
| 69 | ||
| 70 | /* Temporarily setting TZ to 1 for UTC */ | |
| 71 | setenv("TZ", "", 1); | |
| 72 | tzset(); | |
| 73 | ret = mktime(tm); | |
| 74 | if (tz) { | |
| 75 | setenv("TZ", tz, 1); | |
| 76 | free(tz); | |
| 77 | } else { | |
| 78 | unsetenv("TZ"); | |
| 79 | } | |
| 80 | tzset(); | |
| 81 | return ret; | |
| 82 | } | |
| 83 | ||
| 84 | #endif | |
| 85 | ||
| 86 | #endif /* _BABELTRACE_UTC_H */ |