| 1 | /* Provide gettimeofday for systems that don't have it or for which it's broken. |
| 2 | |
| 3 | Copyright (C) 2001-2003, 2005-2007, 2009-2014 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 Lesser General Public License as published by |
| 7 | the Free Software Foundation; either version 2, 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 Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public License |
| 16 | along with this program; if not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | /* written by Jim Meyering */ |
| 19 | |
| 20 | #include <config.h> |
| 21 | |
| 22 | /* Specification. */ |
| 23 | #include <sys/time.h> |
| 24 | |
| 25 | #include <time.h> |
| 26 | |
| 27 | #if HAVE_SYS_TIMEB_H |
| 28 | # include <sys/timeb.h> |
| 29 | #endif |
| 30 | |
| 31 | #if GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME |
| 32 | |
| 33 | /* Work around the bug in some systems whereby gettimeofday clobbers |
| 34 | the static buffer that localtime uses for its return value. The |
| 35 | gettimeofday function from Mac OS X 10.0.4 (i.e., Darwin 1.3.7) has |
| 36 | this problem. The tzset replacement is necessary for at least |
| 37 | Solaris 2.5, 2.5.1, and 2.6. */ |
| 38 | |
| 39 | static struct tm tm_zero_buffer; |
| 40 | static struct tm *localtime_buffer_addr = &tm_zero_buffer; |
| 41 | |
| 42 | # undef localtime |
| 43 | extern struct tm *localtime (time_t const *); |
| 44 | |
| 45 | # undef gmtime |
| 46 | extern struct tm *gmtime (time_t const *); |
| 47 | |
| 48 | /* This is a wrapper for localtime. It is used only on systems for which |
| 49 | gettimeofday clobbers the static buffer used for localtime's result. |
| 50 | |
| 51 | On the first call, record the address of the static buffer that |
| 52 | localtime uses for its result. */ |
| 53 | |
| 54 | struct tm * |
| 55 | rpl_localtime (time_t const *timep) |
| 56 | { |
| 57 | struct tm *tm = localtime (timep); |
| 58 | |
| 59 | if (localtime_buffer_addr == &tm_zero_buffer) |
| 60 | localtime_buffer_addr = tm; |
| 61 | |
| 62 | return tm; |
| 63 | } |
| 64 | |
| 65 | /* Same as above, since gmtime and localtime use the same buffer. */ |
| 66 | struct tm * |
| 67 | rpl_gmtime (time_t const *timep) |
| 68 | { |
| 69 | struct tm *tm = gmtime (timep); |
| 70 | |
| 71 | if (localtime_buffer_addr == &tm_zero_buffer) |
| 72 | localtime_buffer_addr = tm; |
| 73 | |
| 74 | return tm; |
| 75 | } |
| 76 | |
| 77 | #endif /* GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME */ |
| 78 | |
| 79 | #if TZSET_CLOBBERS_LOCALTIME |
| 80 | |
| 81 | # undef tzset |
| 82 | extern void tzset (void); |
| 83 | |
| 84 | /* This is a wrapper for tzset, for systems on which tzset may clobber |
| 85 | the static buffer used for localtime's result. */ |
| 86 | void |
| 87 | rpl_tzset (void) |
| 88 | { |
| 89 | /* Save and restore the contents of the buffer used for localtime's |
| 90 | result around the call to tzset. */ |
| 91 | struct tm save = *localtime_buffer_addr; |
| 92 | tzset (); |
| 93 | *localtime_buffer_addr = save; |
| 94 | } |
| 95 | #endif |
| 96 | |
| 97 | /* This is a wrapper for gettimeofday. It is used only on systems |
| 98 | that lack this function, or whose implementation of this function |
| 99 | causes problems. */ |
| 100 | |
| 101 | int |
| 102 | gettimeofday (struct timeval *restrict tv, void *restrict tz) |
| 103 | { |
| 104 | #undef gettimeofday |
| 105 | #if HAVE_GETTIMEOFDAY |
| 106 | # if GETTIMEOFDAY_CLOBBERS_LOCALTIME |
| 107 | /* Save and restore the contents of the buffer used for localtime's |
| 108 | result around the call to gettimeofday. */ |
| 109 | struct tm save = *localtime_buffer_addr; |
| 110 | # endif |
| 111 | |
| 112 | # if defined timeval /* 'struct timeval' overridden by gnulib? */ |
| 113 | # undef timeval |
| 114 | struct timeval otv; |
| 115 | int result = gettimeofday (&otv, (struct timezone *) tz); |
| 116 | if (result == 0) |
| 117 | { |
| 118 | tv->tv_sec = otv.tv_sec; |
| 119 | tv->tv_usec = otv.tv_usec; |
| 120 | } |
| 121 | # else |
| 122 | int result = gettimeofday (tv, (struct timezone *) tz); |
| 123 | # endif |
| 124 | |
| 125 | # if GETTIMEOFDAY_CLOBBERS_LOCALTIME |
| 126 | *localtime_buffer_addr = save; |
| 127 | # endif |
| 128 | |
| 129 | return result; |
| 130 | |
| 131 | #else |
| 132 | |
| 133 | # if HAVE__FTIME |
| 134 | |
| 135 | struct _timeb timebuf; |
| 136 | _ftime (&timebuf); |
| 137 | tv->tv_sec = timebuf.time; |
| 138 | tv->tv_usec = timebuf.millitm * 1000; |
| 139 | |
| 140 | # else |
| 141 | |
| 142 | # if !defined OK_TO_USE_1S_CLOCK |
| 143 | # error "Only 1-second nominal clock resolution found. Is that intended?" \ |
| 144 | "If so, compile with the -DOK_TO_USE_1S_CLOCK option." |
| 145 | # endif |
| 146 | tv->tv_sec = time (NULL); |
| 147 | tv->tv_usec = 0; |
| 148 | |
| 149 | # endif |
| 150 | |
| 151 | return 0; |
| 152 | |
| 153 | #endif |
| 154 | } |