From 6fadf3311a2450d4dcb0f6f2346b56aafff92df1 Mon Sep 17 00:00:00 2001
From: ksss <co000ri@gmail.com>
Date: Fri, 18 Dec 2020 16:50:11 +0900
Subject: [PATCH] Implement File.birthtime

On linux could not use File::Stat#birthtime.
But it can call if use `statx(2)`
---
 Rakefile          | 12 ++++++++++++
 config.h.in       |  3 +++
 configure         | 11 +++++++++++
 configure.ac      |  1 +
 src/file-stat.c   | 38 ++++++++++++++++++++++++++++++++++++++
 test/file-stat.rb |  8 ++++++++
 6 files changed, 73 insertions(+)

diff --git a/Rakefile b/Rakefile
index b3ce7cd..0112ec4 100644
--- a/Rakefile
+++ b/Rakefile
@@ -16,3 +16,15 @@ task :test => "#{mruby_dir}/ci_build_config.rb" do
     sh "rake -E 'STDOUT.sync=true' test all MRUBY_CONFIG=ci_build_config.rb"
   end
 end
+
+file 'configure' => 'configure.ac' do
+  sh 'autoconf'
+end
+
+file 'config.h.in' => 'configure.ac' do
+  sh 'autoheader'
+  sh 'rm -f config.h.in~'
+end
+
+desc "update"
+task :update => ['configure', 'config.h.in']
diff --git a/config.h.in b/config.h.in
index 5a6c4ea..ab3b419 100644
--- a/config.h.in
+++ b/config.h.in
@@ -12,6 +12,9 @@
 /* Define to 1 if you have the <memory.h> header file. */
 #undef HAVE_MEMORY_H
 
+/* Define to 1 if you have the `statx' function. */
+#undef HAVE_STATX
+
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
diff --git a/configure b/configure
index 6fc5869..817479d 100755
--- a/configure
+++ b/configure
@@ -3478,6 +3478,17 @@ _ACEOF
 fi
 done
 
+for ac_func in statx
+do :
+  ac_fn_c_check_func "$LINENO" "statx" "ac_cv_func_statx"
+if test "x$ac_cv_func_statx" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_STATX 1
+_ACEOF
+
+fi
+done
+
 
 for ac_header in sys/sysmacros.h
 do :
diff --git a/configure.ac b/configure.ac
index 2883e8b..43dcda6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,6 +26,7 @@ AC_CHECK_MEMBERS([struct stat.st_birthtimespec])
 
 AC_CHECK_FUNCS(getgroups)
 AC_CHECK_FUNCS(lstat)
+AC_CHECK_FUNCS(statx)
 
 AC_CHECK_HEADERS(sys/sysmacros.h)
 
diff --git a/src/file-stat.c b/src/file-stat.c
index fa2e000..47d17f5 100644
--- a/src/file-stat.c
+++ b/src/file-stat.c
@@ -465,6 +465,43 @@ stat_ctime(mrb_state *mrb, mrb_value self)
   return time_at_with_sec_nsec(mrb, ts.tv_sec, ts.tv_nsec);
 }
 
+#if defined(HAVE_STATX)
+static mrb_value
+file_s_birthtime(mrb_state *mrb, mrb_value klass)
+{
+  struct statx *stx;
+  char *locale_path;
+  char *path = NULL;
+  int statx_result;
+
+  mrb_get_args(mrb, "z", &path);
+
+  locale_path = mrb_locale_from_utf8(path, -1);
+  statx_result = statx(AT_FDCWD, locale_path, 0, STATX_BTIME, &stx);
+  mrb_locale_free(locale_path);
+  if (statx_result == -1) {
+    mrb_sys_fail(mrb, path);
+  }
+  if (!(stx->stx_mask & STATX_BTIME)) {
+    /* birthtime is not supported on the filesystem */
+    errno = ENOSYS;
+    mrb_sys_fail(mrb, path);
+  }
+  return time_at_with_src_nsec(mrb, stx->stx_btime.tv_sec, stx->stx_btime.tv_nsec);
+}
+#else
+static mrb_value
+file_s_birthtime(mrb_state *mrb, mrb_value klass)
+{
+  mrb_value path;
+  mrb_value stat;
+
+  mrb_get_args(mrb, "S", &path);
+  stat = mrb_funcall(mrb, klass, "stat", 1, path);
+  return mrb_funcall(mrb, stat, "birthtime", 0);
+}
+#endif
+
 #if defined(HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC)
 static mrb_value
 stat_birthtime(mrb_state *mrb, mrb_value self)
@@ -898,6 +935,7 @@ mrb_mruby_file_stat_gem_init(mrb_state* mrb)
   mrb_define_method(mrb, io, "stat", io_stat, MRB_ARGS_NONE());
 
   mrb_define_class_method(mrb, file, "lstat", file_s_lstat, MRB_ARGS_REQ(1));
+  mrb_define_class_method(mrb, file, "birthtime", file_s_birthtime, MRB_ARGS_REQ(1));
 
   mrb_define_method(mrb, stat, "initialize", stat_initialize, MRB_ARGS_REQ(1));
   mrb_define_method(mrb, stat, "initialize_copy", stat_initialize_copy, MRB_ARGS_REQ(1));
diff --git a/test/file-stat.rb b/test/file-stat.rb
index 28d871e..c7e94a1 100644
--- a/test/file-stat.rb
+++ b/test/file-stat.rb
@@ -22,6 +22,14 @@ def chmod(mode, path)
   assert_kind_of File::Stat, File.lstat('README.md')
 end
 
+assert 'File.birthtime' do
+  begin
+    assert_kind_of Time, File.birthtime('README.md')
+  rescue NotImplementedError
+    skip 'This system not supported `birthtime`'
+  end
+end
+
 assert 'File::Stat#initialize_copy' do
   orig = File::Stat.new('README.md')
   copy = orig.dup