From 8f98de10ba6170e4e127f06f02f07c2d754da6d0 Mon Sep 17 00:00:00 2001
From: Theodore Dubois <tblodt@icloud.com>
Date: Tue, 2 May 2023 21:00:51 -0700
Subject: [PATCH] Export and import file timestamps

---
 tools/fakefs.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/tools/fakefs.c b/tools/fakefs.c
index 118ec8d78d..f24694cc3d 100644
--- a/tools/fakefs.c
+++ b/tools/fakefs.c
@@ -188,6 +188,20 @@ bool fakefs_import(const char *archive_path, const char *fs, struct fakefsify_er
         if (fd != -1)
             close(fd);
 
+        struct timespec times[2] = {
+            // for utimes, atime is first, mtime is second
+            {.tv_sec = archive_entry_atime(entry), .tv_nsec = archive_entry_atime_nsec(entry)},
+            {.tv_sec = archive_entry_mtime(entry), .tv_nsec = archive_entry_mtime_nsec(entry)},
+            // utimes cannot set ctime
+        };
+        if (!archive_entry_atime_is_set(entry))
+            times[0].tv_nsec = UTIME_OMIT;
+        if (!archive_entry_mtime_is_set(entry))
+            times[1].tv_nsec = UTIME_OMIT;
+        err = utimensat(root_fd, fix_path(entry_path), times, 0);
+        if (err < 0)
+            POSIX_ERR();
+
         struct ish_stat stat = {
             .mode = (uint32_t) archive_entry_mode(entry),
             .uid = (uint32_t) archive_entry_uid(entry),
@@ -231,7 +245,7 @@ bool fakefs_export(const char *fs, const char *archive_path, struct fakefsify_er
     if (archive == NULL)
         ARCHIVE_ERR(archive);
     archive_write_add_filter_gzip(archive);
-    archive_write_set_format_pax_restricted(archive);
+    archive_write_set_format_pax(archive);
     if (archive_write_open_filename(archive, archive_path) != ARCHIVE_OK)
         ARCHIVE_ERR(archive);
 
@@ -256,7 +270,7 @@ bool fakefs_export(const char *fs, const char *archive_path, struct fakefsify_er
     int64_t paths_done = 0;
 
     struct archive_entry_linkresolver *linkresolver = archive_entry_linkresolver_new();
-    archive_entry_linkresolver_set_strategy(linkresolver, ARCHIVE_FORMAT_TAR_PAX_RESTRICTED);
+    archive_entry_linkresolver_set_strategy(linkresolver, ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE);
 
     sqlite3_stmt *query = PREPARE("select path, inode, stat from paths, stats using (inode)");
     while (STEP(query)) {
@@ -289,6 +303,14 @@ bool fakefs_export(const char *fs, const char *archive_path, struct fakefsify_er
             POSIX_ERR();
         }
         archive_entry_set_size(entry, real_stat.st_size);
+#if __APPLE__
+#define TIMESPEC(x) st_##x##timespec
+#elif __linux__
+#define TIMESPEC(x) st_##x##tim
+#endif
+        archive_entry_set_atime(entry, real_stat.st_atime, real_stat.TIMESPEC(a).tv_nsec);
+        archive_entry_set_mtime(entry, real_stat.st_mtime, real_stat.TIMESPEC(m).tv_nsec);
+        archive_entry_set_ctime(entry, real_stat.st_ctime, real_stat.TIMESPEC(c).tv_nsec);
 
         int fd = -1;
         S_IFMT;