lib/stat-time.h

   1 /* stat-related time functions.
   2
   3    Copyright (C) 2005, 2007, 2009-2017 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 #ifdef __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 /* STAT_TIMESPEC (ST, ST_XTIM) is the ST_XTIM member for *ST of type
  39    struct timespec, if available.  If not, then STAT_TIMESPEC_NS (ST,
  40    ST_XTIM) is the nanosecond component of the ST_XTIM member for *ST,
  41    if available.  ST_XTIM can be st_atim, st_ctim, st_mtim, or st_birthtim
  42    for access, status change, data modification, or birth (creation)
  43    time respectively.
  44
  45    These macros are private to stat-time.h.  */
  46 #if _GL_WINDOWS_STAT_TIMESPEC || defined HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
  47 # if _GL_WINDOWS_STAT_TIMESPEC || defined TYPEOF_STRUCT_STAT_ST_ATIM_IS_STRUCT_TIMESPEC
  48 #  define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim)
  49 # else
  50 #  define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.tv_nsec)
  51 # endif
  52 #elif defined HAVE_STRUCT_STAT_ST_ATIMESPEC_TV_NSEC
  53 # define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim##espec)
  54 #elif defined HAVE_STRUCT_STAT_ST_ATIMENSEC
  55 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim##ensec)
  56 #elif defined HAVE_STRUCT_STAT_ST_ATIM_ST__TIM_TV_NSEC
  57 # define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.st__tim.tv_nsec)
  58 #endif
  59
  60 /* Return the nanosecond component of *ST's access time.  */
  61 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  62 get_stat_atime_ns (struct stat const *st)
  63 {
  64 # if defined STAT_TIMESPEC
  65   return STAT_TIMESPEC (st, st_atim).tv_nsec;
  66 # elif defined STAT_TIMESPEC_NS
  67   return STAT_TIMESPEC_NS (st, st_atim);
  68 # else
  69   return 0;
  70 # endif
  71 }
  72
  73 /* Return the nanosecond component of *ST's status change time.  */
  74 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  75 get_stat_ctime_ns (struct stat const *st)
  76 {
  77 # if defined STAT_TIMESPEC
  78   return STAT_TIMESPEC (st, st_ctim).tv_nsec;
  79 # elif defined STAT_TIMESPEC_NS
  80   return STAT_TIMESPEC_NS (st, st_ctim);
  81 # else
  82   return 0;
  83 # endif
  84 }
  85
  86 /* Return the nanosecond component of *ST's data modification time.  */
  87 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
  88 get_stat_mtime_ns (struct stat const *st)
  89 {
  90 # if defined STAT_TIMESPEC
  91   return STAT_TIMESPEC (st, st_mtim).tv_nsec;
  92 # elif defined STAT_TIMESPEC_NS
  93   return STAT_TIMESPEC_NS (st, st_mtim);
  94 # else
  95   return 0;
  96 # endif
  97 }
  98
  99 /* Return the nanosecond component of *ST's birth time.  */
 100 _GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
 101 get_stat_birthtime_ns (struct stat const *st)
 102 {
 103 # if defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC
 104   return STAT_TIMESPEC (st, st_birthtim).tv_nsec;
 105 # elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
 106   return STAT_TIMESPEC_NS (st, st_birthtim);
 107 # else
 108   /* Avoid a "parameter unused" warning.  */
 109   (void) st;
 110   return 0;
 111 # endif
 112 }
 113
 114 /* Return *ST's access time.  */
 115 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 116 get_stat_atime (struct stat const *st)
 117 {
 118 #ifdef STAT_TIMESPEC
 119   return STAT_TIMESPEC (st, st_atim);
 120 #else
 121   struct timespec t;
 122   t.tv_sec = st->st_atime;
 123   t.tv_nsec = get_stat_atime_ns (st);
 124   return t;
 125 #endif
 126 }
 127
 128 /* Return *ST's status change time.  */
 129 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 130 get_stat_ctime (struct stat const *st)
 131 {
 132 #ifdef STAT_TIMESPEC
 133   return STAT_TIMESPEC (st, st_ctim);
 134 #else
 135   struct timespec t;
 136   t.tv_sec = st->st_ctime;
 137   t.tv_nsec = get_stat_ctime_ns (st);
 138   return t;
 139 #endif
 140 }
 141
 142 /* Return *ST's data modification time.  */
 143 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 144 get_stat_mtime (struct stat const *st)
 145 {
 146 #ifdef STAT_TIMESPEC
 147   return STAT_TIMESPEC (st, st_mtim);
 148 #else
 149   struct timespec t;
 150   t.tv_sec = st->st_mtime;
 151   t.tv_nsec = get_stat_mtime_ns (st);
 152   return t;
 153 #endif
 154 }
 155
 156 /* Return *ST's birth time, if available; otherwise return a value
 157    with tv_sec and tv_nsec both equal to -1.  */
 158 _GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
 159 get_stat_birthtime (struct stat const *st)
 160 {
 161   struct timespec t;
 162
 163 #if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
 164      || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC)
 165   t = STAT_TIMESPEC (st, st_birthtim);
 166 #elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
 167   t.tv_sec = st->st_birthtime;
 168   t.tv_nsec = st->st_birthtimensec;
 169 #elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 170   /* Native Windows platforms (but not Cygwin) put the "file creation
 171      time" in st_ctime (!).  See
 172      <https://msdn.microsoft.com/en-us/library/14h5k7ff(VS.80).aspx>.  */
 173 # if _GL_WINDOWS_STAT_TIMESPEC
 174   t = st->st_ctim;
 175 # else
 176   t.tv_sec = st->st_ctime;
 177   t.tv_nsec = 0;
 178 # endif
 179 #else
 180   /* Birth time is not supported.  */
 181   t.tv_sec = -1;
 182   t.tv_nsec = -1;
 183   /* Avoid a "parameter unused" warning.  */
 184   (void) st;
 185 #endif
 186
 187 #if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
 188      || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC \
 189      || defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC)
 190   /* FreeBSD and NetBSD sometimes signal the absence of knowledge by
 191      using zero.  Attempt to work around this problem.  Alas, this can
 192      report failure even for valid timestamps.  Also, NetBSD
 193      sometimes returns junk in the birth time fields; work around this
 194      bug if it is detected.  */
 195   if (! (t.tv_sec && 0 <= t.tv_nsec && t.tv_nsec < 1000000000))
 196     {
 197       t.tv_sec = -1;
 198       t.tv_nsec = -1;
 199     }
 200 #endif
 201
 202   return t;
 203 }
 204
 205 #ifdef __cplusplus
 206 }
 207 #endif
 208
 209 _GL_INLINE_HEADER_END
 210
 211 #endif