From 1e6719abe9f90a71dc0a58537b93bc38fc89c5de Mon Sep 17 00:00:00 2001
From: Andrei Tatar <andrei@unikraft.io>
Date: Wed, 27 Mar 2024 15:37:31 +0100
Subject: [PATCH] lib/posix-fdio: Add internal futime(n)s syscalls

This change adds internal API variants of futimes and futimens.

Checkpatch-Ignore: MACRO_ARG_REUSE
Signed-off-by: Andrei Tatar <andrei@unikraft.io>
Approved-by: Sergiu Moga <sergiu@unikraft.io>
Reviewed-by: Sergiu Moga <sergiu@unikraft.io>
GitHub-Closes: #1575
---
 lib/posix-fdio/Config.uk               |  2 +
 lib/posix-fdio/fdstat.c                | 67 ++++++++++++++++++++++++++
 lib/posix-fdio/include/uk/posix-fdio.h |  5 ++
 3 files changed, 74 insertions(+)

diff --git a/lib/posix-fdio/Config.uk b/lib/posix-fdio/Config.uk
index e11a933ac..47264a8a5 100644
--- a/lib/posix-fdio/Config.uk
+++ b/lib/posix-fdio/Config.uk
@@ -2,5 +2,7 @@ config LIBPOSIX_FDIO
 	bool "posix-fdio: File I/O and control"
 	select LIBUKATOMIC
 	select LIBUKFILE
+	select LIBPOSIX_TIME
+	select LIBUKTIMECONV
 	select LIBPOSIX_FDTAB
 	select LIBPOSIX_FDTAB_LEGACY_SHIM
diff --git a/lib/posix-fdio/fdstat.c b/lib/posix-fdio/fdstat.c
index 80d653043..8638c3416 100644
--- a/lib/posix-fdio/fdstat.c
+++ b/lib/posix-fdio/fdstat.c
@@ -9,9 +9,16 @@
 #include <string.h>
 
 #include <uk/posix-fdio.h>
+#include <uk/posix-time.h>
+#include <uk/timeutil.h>
 
 #include "fdio-impl.h"
 
+#define statx_time(ts) ((struct uk_statx_timestamp){ \
+	.tv_sec = (ts).tv_sec, \
+	.tv_nsec = (ts).tv_nsec \
+})
+
 static inline
 dev_t nums2dev(__u32 major, __u32 minor)
 {
@@ -117,3 +124,63 @@ int uk_sys_fchown(struct uk_ofile *of, uid_t owner, gid_t group)
 		uk_file_wunlock(of->file);
 	return r;
 }
+
+int uk_sys_futimens(struct uk_ofile *of, const struct timespec *times)
+{
+	int r;
+	unsigned int mask;
+	struct uk_statx sx;
+	struct timespec t;
+	const int iolock = _SHOULD_LOCK(of->mode);
+
+	/* TODO: check if uid is root or file owner for custom times */
+
+	if (!times ||
+	    times[0].tv_nsec == UTIME_NOW || times[1].tv_nsec == UTIME_NOW) {
+		r = uk_sys_clock_gettime(CLOCK_REALTIME, &t);
+		if (unlikely(r)) {
+			UK_ASSERT(r < 0);
+			/* The futime(n)s manpages do not specify an error case
+			 * for failing to get the current time, and failure of
+			 * the above call may indicate a misconfigured kernel.
+			 * Print a warning before erroring out.
+			 */
+			uk_pr_warn("Failed to get current time: %d\n", r);
+			return r;
+		}
+	}
+
+	if (!times) {
+		mask = UK_STATX_ATIME | UK_STATX_MTIME;
+		sx.stx_atime = statx_time(t);
+		sx.stx_mtime = statx_time(t);
+	} else {
+		mask = 0;
+		if (times[0].tv_nsec != UTIME_OMIT) {
+			mask |= UK_STATX_ATIME;
+			if (times[0].tv_nsec == UTIME_NOW)
+				sx.stx_atime = statx_time(t);
+			else
+				sx.stx_atime = statx_time(times[0]);
+		}
+		if (times[1].tv_nsec != UTIME_OMIT) {
+			mask |= UK_STATX_MTIME;
+			if (times[1].tv_nsec == UTIME_NOW)
+				sx.stx_mtime = statx_time(t);
+			else
+				sx.stx_mtime = statx_time(times[1]);
+		}
+	}
+
+	if (iolock)
+		uk_file_wlock(of->file);
+	r = uk_file_setstat(of->file, mask, &sx);
+	if (iolock)
+		uk_file_wunlock(of->file);
+	return r;
+}
+
+int uk_sys_futimes(struct uk_ofile *of, const struct timeval *tv)
+{
+	return uk_sys_futimens(of, tv ? &uk_time_spec_from_val(tv) : NULL);
+}
diff --git a/lib/posix-fdio/include/uk/posix-fdio.h b/lib/posix-fdio/include/uk/posix-fdio.h
index e05182458..4ee445ece 100644
--- a/lib/posix-fdio/include/uk/posix-fdio.h
+++ b/lib/posix-fdio/include/uk/posix-fdio.h
@@ -10,6 +10,7 @@
 #define __UK_POSIX_FDIO_H__
 
 #include <sys/stat.h>
+#include <sys/time.h>
 
 #include <uk/posix-fd.h>
 
@@ -67,6 +68,10 @@ int uk_sys_fchmod(struct uk_ofile *of, mode_t mode);
 
 int uk_sys_fchown(struct uk_ofile *of, uid_t owner, gid_t group);
 
+int uk_sys_futimes(struct uk_ofile *of, const struct timeval *tv);
+
+int uk_sys_futimens(struct uk_ofile *of, const struct timespec *times);
+
 /* Control */
 
 int uk_sys_ioctl(struct uk_ofile *of, int cmd, void *arg);
-- 
2.39.5