lib/stat-time.h

   1 /* stat-related time functions.
   2
   3    Copyright (C) 2005, 2007, 2009-2016 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 #ifndef _GL_INLINE_HEADER_BEGIN
  27  #error "Please include config.h first."
  28 #endif
  29 _GL_INLINE_HEADER_BEGIN
  30 #ifndef _GL_STAT_TIME_INLINE
  31 # define _GL_STAT_TIME_INLINE _GL_INLINE
  32 #endif
  33
  34 /* STAT_TIMESPEC (ST, ST_XTIM) is the ST_XTIM member for *ST of type
  35    struct timespec, if available.  If not, then STAT_TIMESPEC_NS (ST,
  36    ST_XTIM) is the nanosecond component of the ST_XTIM member for *ST,
  37    if available.  ST_XTIM can be st_atim, st_ctim, st_mtim, or st_birthtim
  38    for access, status change, data modification, or birth (creation)
  39    time respectively.
  40
  41    These macros are private to stat-time.h.  */
  42 #if defined HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
  43 # ifdef TYPEOF_STRUCT_STAT_ST_ATIM_IS_STRUCT_TIMESPEC
  44 #  define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim)
  45 # else
  46 #  define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.tv_nsec)
  47 # endif
  48 #elif defined HAVE_STRUCT_STAT_ST_ATIMESPEC_TV_NSEC
  49 # define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim##espec)
  50 #elif defined HAVE_STRUCT_STAT_ST_ATIMENSEC
  51 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim##ensec)
  52 #elif defined HAVE_STRUCT_STAT_ST_ATIM_ST__TIM_TV_NSEC
  53 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.st__tim.tv_nsec)
  54 #endif
  55
  56 /* Return the nanosecond component of *ST's access time.  */
  57 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  58 get_stat_atime_ns (struct stat const *st)
  59 {
  60 # if defined STAT_TIMESPEC
  61   return STAT_TIMESPEC (st, st_atim).tv_nsec;
  62 # elif defined STAT_TIMESPEC_NS
  63   return STAT_TIMESPEC_NS (st, st_atim);
  64 # else
  65   return 0;
  66 # endif
  67 }
  68
  69 /* Return the nanosecond component of *ST's status change time.  */
  70 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  71 get_stat_ctime_ns (struct stat const *st)
  72 {
  73 # if defined STAT_TIMESPEC
  74   return STAT_TIMESPEC (st, st_ctim).tv_nsec;
  75 # elif defined STAT_TIMESPEC_NS
  76   return STAT_TIMESPEC_NS (st, st_ctim);
  77 # else
  78   return 0;
  79 # endif
  80 }
  81
  82 /* Return the nanosecond component of *ST's data modification time.  */
  83 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  84 get_stat_mtime_ns (struct stat const *st)
  85 {
  86 # if defined STAT_TIMESPEC
  87   return STAT_TIMESPEC (st, st_mtim).tv_nsec;
  88 # elif defined STAT_TIMESPEC_NS
  89   return STAT_TIMESPEC_NS (st, st_mtim);
  90 # else
  91   return 0;
  92 # endif
  93 }
  94
  95 /* Return the nanosecond component of *ST's birth time.  */
  96 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  97 get_stat_birthtime_ns (struct stat const *st)
  98 {
  99 # if defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC
 100   return STAT_TIMESPEC (st, st_birthtim).tv_nsec;
 101 # elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
 102   return STAT_TIMESPEC_NS (st, st_birthtim);
 103 # else
 104   /* Avoid a "parameter unused" warning.  */
 105   (void) st;
 106   return 0;
 107 # endif
 108 }
 109
 110 /* Return *ST's access time.  */
 111 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 112 get_stat_atime (struct stat const *st)
 113 {
 114 #ifdef STAT_TIMESPEC
 115   return STAT_TIMESPEC (st, st_atim);
 116 #else
 117   struct timespec t;
 118   t.tv_sec = st->st_atime;
 119   t.tv_nsec = get_stat_atime_ns (st);
 120   return t;
 121 #endif
 122 }
 123
 124 /* Return *ST's status change time.  */
 125 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 126 get_stat_ctime (struct stat const *st)
 127 {
 128 #ifdef STAT_TIMESPEC
 129   return STAT_TIMESPEC (st, st_ctim);
 130 #else
 131   struct timespec t;
 132   t.tv_sec = st->st_ctime;
 133   t.tv_nsec = get_stat_ctime_ns (st);
 134   return t;
 135 #endif
 136 }
 137
 138 /* Return *ST's data modification time.  */
 139 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 140 get_stat_mtime (struct stat const *st)
 141 {
 142 #ifdef STAT_TIMESPEC
 143   return STAT_TIMESPEC (st, st_mtim);
 144 #else
 145   struct timespec t;
 146   t.tv_sec = st->st_mtime;
 147   t.tv_nsec = get_stat_mtime_ns (st);
 148   return t;
 149 #endif
 150 }
 151
 152 /* Return *ST's birth time, if available; otherwise return a value
 153    with tv_sec and tv_nsec both equal to -1.  */
 154 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 155 get_stat_birthtime (struct stat const *st)
 156 {
 157   struct timespec t;
 158
 159 #if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
 160      || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC)
 161   t = STAT_TIMESPEC (st, st_birthtim);
 162 #elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
 163   t.tv_sec = st->st_birthtime;
 164   t.tv_nsec = st->st_birthtimensec;
 165 #elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 166   /* Native Windows platforms (but not Cygwin) put the "file creation
 167      time" in st_ctime (!).  See
 168      <http://msdn2.microsoft.com/de-de/library/14h5k7ff(VS.80).aspx>.  */
 169   t.tv_sec = st->st_ctime;
 170   t.tv_nsec = 0;
 171 #else
 172   /* Birth time is not supported.  */
 173   t.tv_sec = -1;
 174   t.tv_nsec = -1;
 175   /* Avoid a "parameter unused" warning.  */
 176   (void) st;
 177 #endif
 178
 179 #if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
 180      || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC \
 181      || defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC)
 182   /* FreeBSD and NetBSD sometimes signal the absence of knowledge by
 183      using zero.  Attempt to work around this problem.  Alas, this can
 184      report failure even for valid time stamps.  Also, NetBSD
 185      sometimes returns junk in the birth time fields; work around this
 186      bug if it is detected.  */
 187   if (! (t.tv_sec && 0 <= t.tv_nsec && t.tv_nsec < 1000000000))
 188     {
 189       t.tv_sec = -1;
 190       t.tv_nsec = -1;
 191     }
 192 #endif
 193
 194   return t;
 195 }
 196
 197 _GL_INLINE_HEADER_END
 198
 199 #endif