summaryrefslogtreecommitdiffstats
path: root/lib/stat-time.h
diff options
context:
space:
mode:
Diffstat (limited to 'lib/stat-time.h')
-rw-r--r--lib/stat-time.h252
1 files changed, 252 insertions, 0 deletions
diff --git a/lib/stat-time.h b/lib/stat-time.h
new file mode 100644
index 0000000..884ffd8
--- /dev/null
+++ b/lib/stat-time.h
@@ -0,0 +1,252 @@
+/* stat-related time functions.
+
+ Copyright (C) 2005, 2007, 2009-2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Paul Eggert. */
+
+#ifndef STAT_TIME_H
+#define STAT_TIME_H 1
+
+#include "intprops.h"
+
+#include <errno.h>
+#include <stddef.h>
+#include <sys/stat.h>
+#include <time.h>
+
+#ifndef _GL_INLINE_HEADER_BEGIN
+ #error "Please include config.h first."
+#endif
+_GL_INLINE_HEADER_BEGIN
+#ifndef _GL_STAT_TIME_INLINE
+# define _GL_STAT_TIME_INLINE _GL_INLINE
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* STAT_TIMESPEC (ST, ST_XTIM) is the ST_XTIM member for *ST of type
+ struct timespec, if available. If not, then STAT_TIMESPEC_NS (ST,
+ ST_XTIM) is the nanosecond component of the ST_XTIM member for *ST,
+ if available. ST_XTIM can be st_atim, st_ctim, st_mtim, or st_birthtim
+ for access, status change, data modification, or birth (creation)
+ time respectively.
+
+ These macros are private to stat-time.h. */
+#if _GL_WINDOWS_STAT_TIMESPEC || defined HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
+# if _GL_WINDOWS_STAT_TIMESPEC || defined TYPEOF_STRUCT_STAT_ST_ATIM_IS_STRUCT_TIMESPEC
+# define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim)
+# else
+# define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.tv_nsec)
+# endif
+#elif defined HAVE_STRUCT_STAT_ST_ATIMESPEC_TV_NSEC
+# define STAT_TIMESPEC(st, st_xtim) ((st)->st_xtim##espec)
+#elif defined HAVE_STRUCT_STAT_ST_ATIMENSEC
+# define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim##ensec)
+#elif defined HAVE_STRUCT_STAT_ST_ATIM_ST__TIM_TV_NSEC
+# define STAT_TIMESPEC_NS(st, st_xtim) ((st)->st_xtim.st__tim.tv_nsec)
+#endif
+
+/* Return the nanosecond component of *ST's access time. */
+_GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
+get_stat_atime_ns (struct stat const *st)
+{
+# if defined STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_atim).tv_nsec;
+# elif defined STAT_TIMESPEC_NS
+ return STAT_TIMESPEC_NS (st, st_atim);
+# else
+ return 0;
+# endif
+}
+
+/* Return the nanosecond component of *ST's status change time. */
+_GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
+get_stat_ctime_ns (struct stat const *st)
+{
+# if defined STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_ctim).tv_nsec;
+# elif defined STAT_TIMESPEC_NS
+ return STAT_TIMESPEC_NS (st, st_ctim);
+# else
+ return 0;
+# endif
+}
+
+/* Return the nanosecond component of *ST's data modification time. */
+_GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
+get_stat_mtime_ns (struct stat const *st)
+{
+# if defined STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_mtim).tv_nsec;
+# elif defined STAT_TIMESPEC_NS
+ return STAT_TIMESPEC_NS (st, st_mtim);
+# else
+ return 0;
+# endif
+}
+
+/* Return the nanosecond component of *ST's birth time. */
+_GL_STAT_TIME_INLINE long int _GL_ATTRIBUTE_PURE
+get_stat_birthtime_ns (struct stat const *st _GL_UNUSED)
+{
+# if defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC
+ return STAT_TIMESPEC (st, st_birthtim).tv_nsec;
+# elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
+ return STAT_TIMESPEC_NS (st, st_birthtim);
+# else
+ return 0;
+# endif
+}
+
+/* Return *ST's access time. */
+_GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
+get_stat_atime (struct stat const *st)
+{
+#ifdef STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_atim);
+#else
+ struct timespec t;
+ t.tv_sec = st->st_atime;
+ t.tv_nsec = get_stat_atime_ns (st);
+ return t;
+#endif
+}
+
+/* Return *ST's status change time. */
+_GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
+get_stat_ctime (struct stat const *st)
+{
+#ifdef STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_ctim);
+#else
+ struct timespec t;
+ t.tv_sec = st->st_ctime;
+ t.tv_nsec = get_stat_ctime_ns (st);
+ return t;
+#endif
+}
+
+/* Return *ST's data modification time. */
+_GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
+get_stat_mtime (struct stat const *st)
+{
+#ifdef STAT_TIMESPEC
+ return STAT_TIMESPEC (st, st_mtim);
+#else
+ struct timespec t;
+ t.tv_sec = st->st_mtime;
+ t.tv_nsec = get_stat_mtime_ns (st);
+ return t;
+#endif
+}
+
+/* Return *ST's birth time, if available; otherwise return a value
+ with tv_sec and tv_nsec both equal to -1. */
+_GL_STAT_TIME_INLINE struct timespec _GL_ATTRIBUTE_PURE
+get_stat_birthtime (struct stat const *st _GL_UNUSED)
+{
+ struct timespec t;
+
+#if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
+ || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC)
+ t = STAT_TIMESPEC (st, st_birthtim);
+#elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
+ t.tv_sec = st->st_birthtime;
+ t.tv_nsec = st->st_birthtimensec;
+#elif defined _WIN32 && ! defined __CYGWIN__
+ /* Native Windows platforms (but not Cygwin) put the "file creation
+ time" in st_ctime (!). See
+ <https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/stat-functions>. */
+# if _GL_WINDOWS_STAT_TIMESPEC
+ t = st->st_ctim;
+# else
+ t.tv_sec = st->st_ctime;
+ t.tv_nsec = 0;
+# endif
+#else
+ /* Birth time is not supported. */
+ t.tv_sec = -1;
+ t.tv_nsec = -1;
+#endif
+
+#if (defined HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC \
+ || defined HAVE_STRUCT_STAT_ST_BIRTHTIM_TV_NSEC \
+ || defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC)
+ /* FreeBSD and NetBSD sometimes signal the absence of knowledge by
+ using zero. Attempt to work around this problem. Alas, this can
+ report failure even for valid timestamps. Also, NetBSD
+ sometimes returns junk in the birth time fields; work around this
+ bug if it is detected. */
+ if (! (t.tv_sec && 0 <= t.tv_nsec && t.tv_nsec < 1000000000))
+ {
+ t.tv_sec = -1;
+ t.tv_nsec = -1;
+ }
+#endif
+
+ return t;
+}
+
+/* If a stat-like function returned RESULT, normalize the timestamps
+ in *ST, in case this platform suffers from the Solaris 11 bug where
+ tv_nsec might be negative. Return the adjusted RESULT, setting
+ errno to EOVERFLOW if normalization overflowed. This function
+ is intended to be private to this .h file. */
+_GL_STAT_TIME_INLINE int
+stat_time_normalize (int result, struct stat *st _GL_UNUSED)
+{
+#if defined __sun && defined STAT_TIMESPEC
+ if (result == 0)
+ {
+ long int timespec_hz = 1000000000;
+ short int const ts_off[] = { offsetof (struct stat, st_atim),
+ offsetof (struct stat, st_mtim),
+ offsetof (struct stat, st_ctim) };
+ int i;
+ for (i = 0; i < sizeof ts_off / sizeof *ts_off; i++)
+ {
+ struct timespec *ts = (struct timespec *) ((char *) st + ts_off[i]);
+ long int q = ts->tv_nsec / timespec_hz;
+ long int r = ts->tv_nsec % timespec_hz;
+ if (r < 0)
+ {
+ r += timespec_hz;
+ q--;
+ }
+ ts->tv_nsec = r;
+ /* Overflow is possible, as Solaris 11 stat can yield
+ tv_sec == TYPE_MINIMUM (time_t) && tv_nsec == -1000000000.
+ INT_ADD_WRAPV is OK, since time_t is signed on Solaris. */
+ if (INT_ADD_WRAPV (q, ts->tv_sec, &ts->tv_sec))
+ {
+ errno = EOVERFLOW;
+ return -1;
+ }
+ }
+ }
+#endif
+ return result;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+_GL_INLINE_HEADER_END
+
+#endif