[vlc-devel] [PATCH v3 3/4] compat: add clock_getres for darwin

[Marvin Scholz]

---
 compat/clock_getres.c | 54 +++++++++++++++++++++++++++++++++++++++++++
 configure.ac          |  2 +-
 include/vlc_fixups.h  |  3 +++
 3 files changed, 58 insertions(+), 1 deletion(-)
 create mode 100644 compat/clock_getres.c

diff --git a/compat/clock_getres.c b/compat/clock_getres.c
new file mode 100644
index 0000000000..b30bcdc96b
--- /dev/null
+++ b/compat/clock_getres.c
@@ -0,0 +1,54 @@
+/*****************************************************************************
+ * clock_getres.c: POSIX clock_getres() replacement
+ *****************************************************************************
+ * Copyright © 2020 VLC authors and VideoLAN
+ *
+ * Author: Marvin Scholz <epirat07 at gmail dot com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#ifdef __APPLE__
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <sys/errno.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <mach/clock_types.h>
+
+int clock_getres(clockid_t clock_id, struct timespec *tp)
+{
+    switch (clock_id) {
+        case CLOCK_MONOTONIC:
+        case CLOCK_REALTIME:
+            // For realtime, it is using gettimeofday and for
+            // the monotonic time it is relative to the system
+            // boot time. Both of these use timeval, which has
+            // at best microsecond precision.
+            tp->tv_sec = 0;
+            tp->tv_nsec = NSEC_PER_USEC;
+            break;
+        default:
+            errno = EINVAL;
+            return -1;
+    }
+
+    return 0;
+}
+
+#endif
diff --git a/configure.ac b/configure.ac
index 59b221b7bb..77520fd1c1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -650,7 +650,7 @@ need_libc=false
 dnl Check for usual libc functions
 AC_CHECK_FUNCS([accept4 daemon fcntl flock fstatat fstatvfs fork getmntent_r getenv getpwuid_r isatty memalign mkostemp mmap open_memstream newlocale pipe2 pread posix_fadvise posix_madvise setlocale stricmp strnicmp strptime uselocale])
 AC_REPLACE_FUNCS([aligned_alloc atof atoll dirfd fdopendir flockfile fsync getdelim getpid lfind lldiv memrchr nrand48 poll posix_memalign recvmsg rewind sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen strnstr strsep strtof strtok_r strtoll swab tdestroy tfind timegm timespec_get strverscmp pathconf])
-AC_REPLACE_FUNCS([gettimeofday clock_gettime clock_nanosleep])
+AC_REPLACE_FUNCS([gettimeofday clock_gettime clock_nanosleep clock_getres])
 AC_CHECK_FUNC(fdatasync,,
   [AC_DEFINE(fdatasync, fsync, [Alias fdatasync() to fsync() if missing.])
 ])
diff --git a/include/vlc_fixups.h b/include/vlc_fixups.h
index a296db0c32..25c7de473e 100644
--- a/include/vlc_fixups.h
+++ b/include/vlc_fixups.h
@@ -672,6 +672,9 @@ FILE *vlc_win32_tmpfile(void);
 # ifndef HAVE_CLOCK_GETTIME
 int clock_gettime(clockid_t clock_id, struct timespec *tp);
 # endif
+# ifndef HAVE_CLOCK_GETRES
+int clock_getres(clockid_t clock_id, struct timespec *tp);
+# endif
 # ifndef HAVE_CLOCK_NANOSLEEP
 int clock_nanosleep(clockid_t clock_id, int flags,
         const struct timespec *rqtp, struct timespec *rmtp);
-- 
2.21.1 (Apple Git-122.3)