| 1 | /* Provide access to the last buffer returned by localtime() or gmtime(). |
| 2 | |
| 3 | Copyright (C) 2001-2003, 2005-2007, 2009-2020 Free Software Foundation, Inc. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3, or (at your option) |
| 8 | any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program; if not, see <https://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | /* written by Jim Meyering */ |
| 19 | |
| 20 | #include <config.h> |
| 21 | |
| 22 | /* Specification. */ |
| 23 | #include "localtime-buffer.h" |
| 24 | |
| 25 | #if GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME |
| 26 | |
| 27 | static struct tm tm_zero_buffer; |
| 28 | struct tm *localtime_buffer_addr = &tm_zero_buffer; |
| 29 | |
| 30 | /* This is a wrapper for localtime. |
| 31 | |
| 32 | On the first call, record the address of the static buffer that |
| 33 | localtime uses for its result. */ |
| 34 | |
| 35 | struct tm * |
| 36 | rpl_localtime (time_t const *timep) |
| 37 | #undef localtime |
| 38 | { |
| 39 | struct tm *tm = localtime (timep); |
| 40 | |
| 41 | if (localtime_buffer_addr == &tm_zero_buffer) |
| 42 | localtime_buffer_addr = tm; |
| 43 | |
| 44 | return tm; |
| 45 | } |
| 46 | |
| 47 | /* Same as above, since gmtime and localtime use the same buffer. */ |
| 48 | struct tm * |
| 49 | rpl_gmtime (time_t const *timep) |
| 50 | #undef gmtime |
| 51 | { |
| 52 | struct tm *tm = gmtime (timep); |
| 53 | |
| 54 | if (localtime_buffer_addr == &tm_zero_buffer) |
| 55 | localtime_buffer_addr = tm; |
| 56 | |
| 57 | return tm; |
| 58 | } |
| 59 | |
| 60 | #endif |