lib/stat-time.h

   1 /* stat-related time functions.
   2
   3    Copyright (C) 2005, 2007, 2009-2012 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 of the License, or
   8    (at your option) 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 <http://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Paul Eggert.  */
  19
  20 #ifndef STAT_TIME_H
  21 #define STAT_TIME_H 1
  22
  23 #include <sys/stat.h>
  24 #include <time.h>
  25
  26 _GL_INLINE_HEADER_BEGIN
  27 #ifndef _GL_STAT_TIME_INLINE
  28 # define _GL_STAT_TIME_INLINE _GL_INLINE
  29 #endif
  30
  31 /* STAT_TIMESPEC (ST, ST_XTIM) is the ST_XTIM member for *ST of type
  32    struct timespec, if available.  If not, then STAT_TIMESPEC_NS (ST,
  33    ST_XTIM) is the nanosecond component of the ST_XTIM member for *ST,
  34    if available.  ST_XTIM can be st_atim, st_ctim, st_mtim, or st_birthtim
  35    for access, status change, data modification, or birth (creation)
  36    time respectively.
  37
  38    These macros are private to stat-time.h.  */
  39 #if defined HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
  40 # ifdef TYPEOF_STRUCT_STAT_ST_ATIM_IS_STRUCT_TIMESPEC
  41 #  define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim)
  42 # else
  43 #  define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.tv_nsec)
  44 # endif
  45 #elif defined HAVE_STRUCT_STAT_ST_ATIMESPEC_TV_NSEC
  46 # define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim##espec)
  47 #elif defined HAVE_STRUCT_STAT_ST_ATIMENSEC
  48 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim##ensec)
  49 #elif defined HAVE_STRUCT_STAT_ST_ATIM_ST__TIM_TV_NSEC
  50 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.st__tim.tv_nsec)
  51 #endif
  52
  53 /* Return the nanosecond component of *ST's access time.  */
  54 _GL_STAT_TIME_INLINE long int
  55 get_stat_atime_ns (struct stat const *st)
  56 {
  57 # if defined STAT_TIMESPEC
  58   return STAT_TIMESPEC (st, st_atim).tv_nsec;
  59 # elif defined STAT_TIMESPEC_NS
  60   return STAT_TIMESPEC_NS (st, st_atim);
  61 # else
  62   return 0;
  63 # endif
  64 }
  65
  66 /* Return the nanosecond component of *ST's status change time.  */
  67 _GL_STAT_TIME_INLINE long int
  68 get_stat_ctime_ns (struct stat const *st)
  69 {
  70 # if defined STAT_TIMESPEC
  71   return STAT_TIMESPEC (st, st_ctim).tv_nsec;
  72 # elif defined STAT_TIMESPEC_NS
  73   return STAT_TIMESPEC_NS (st, st_ctim);
  74 # else
  75   return 0;
  76 # endif
  77 }
  78
  79 /* Return the nanosecond component of *ST's data modification time.  */
  80 _GL_STAT_TIME_INLINE long int
  81 get_stat_mtime_ns (struct stat const *st)
  82 {
  83 # if defined STAT_TIMESPEC
  84   return STAT_TIMESPEC (st, st_mtim).tv_nsec;
  85 # elif defined STAT_TIMESPEC_NS
  86   return STAT_TIMESPEC_NS (st, st_mtim);
  87 # else
  88   return 0;
  89 # endif
  90 }
  91
  92 /* Return the nanosecond component of *ST's birth time.  */
  93 _GL_STAT_TIME_INLINE long int
  94 get_stat_birthtime_ns (struct stat const *st)
  95 {
  96 # if defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC
  97   return STAT_TIMESPEC (st, st_birthtim).tv_nsec;
  98 # elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
  99   return STAT_TIMESPEC_NS (st, st_birthtim);
 100 # else
 101   /* Avoid a "parameter unused" warning.  */
 102   (void) st;
 103   return 0;
 104 # endif
 105 }
 106
 107 /* Return *ST's access time.  */
 108 _GL_STAT_TIME_INLINE struct timespec
 109 get_stat_atime (struct stat const *st)
 110 {
 111 #ifdef STAT_TIMESPEC
 112   return STAT_TIMESPEC (st, st_atim);
 113 #else
 114   struct timespec t;
 115   t.tv_sec = st->st_atime;
 116   t.tv_nsec = get_stat_atime_ns (st);
 117   return t;
 118 #endif
 119 }
 120
 121 /* Return *ST's status change time.  */
 122 _GL_STAT_TIME_INLINE struct timespec
 123 get_stat_ctime (struct stat const *st)
 124 {
 125 #ifdef STAT_TIMESPEC
 126   return STAT_TIMESPEC (st, st_ctim);
 127 #else
 128   struct timespec t;
 129   t.tv_sec = st->st_ctime;
 130   t.tv_nsec = get_stat_ctime_ns (st);
 131   return t;
 132 #endif
 133 }
 134
 135 /* Return *ST's data modification time.  */
 136 _GL_STAT_TIME_INLINE struct timespec
 137 get_stat_mtime (struct stat const *st)
 138 {
 139 #ifdef STAT_TIMESPEC
 140   return STAT_TIMESPEC (st, st_mtim);
 141 #else
 142   struct timespec t;
 143   t.tv_sec = st->st_mtime;
 144   t.tv_nsec = get_stat_mtime_ns (st);
 145   return t;
 146 #endif
 147 }
 148
 149 /* Return *ST's birth time, if available; otherwise return a value
 150    with tv_sec and tv_nsec both equal to -1.  */
 151 _GL_STAT_TIME_INLINE struct timespec
 152 get_stat_birthtime (struct stat const *st)
 153 {
 154   struct timespec t;
 155
 156 #if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
 157      || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC)
 158   t = STAT_TIMESPEC (st, st_birthtim);
 159 #elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
 160   t.tv_sec = st->st_birthtime;
 161   t.tv_nsec = st->st_birthtimensec;
 162 #elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 163   /* Native Windows platforms (but not Cygwin) put the "file creation
 164      time" in st_ctime (!).  See
 165      <http://msdn2.microsoft.com/de-de/library/14h5k7ff(VS.80).aspx>.  */
 166   t.tv_sec = st->st_ctime;
 167   t.tv_nsec = 0;
 168 #else
 169   /* Birth time is not supported.  */
 170   t.tv_sec = -1;
 171   t.tv_nsec = -1;
 172   /* Avoid a "parameter unused" warning.  */
 173   (void) st;
 174 #endif
 175
 176 #if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
 177      || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC \
 178      || defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC)
 179   /* FreeBSD and NetBSD sometimes signal the absence of knowledge by
 180      using zero.  Attempt to work around this problem.  Alas, this can
 181      report failure even for valid time stamps.  Also, NetBSD
 182      sometimes returns junk in the birth time fields; work around this
 183      bug if it is detected.  */
 184   if (! (t.tv_sec && 0 <= t.tv_nsec && t.tv_nsec < 1000000000))
 185     {
 186       t.tv_sec = -1;
 187       t.tv_nsec = -1;
 188     }
 189 #endif
 190
 191   return t;
 192 }
 193
 194 _GL_INLINE_HEADER_END
 195
 196 #endif