From: Joel Rosdahl <joel@rosdahl.net>
Date: Wed, 8 Jun 2022 12:04:55 +0000 (+0200)
Subject: enhance: Add util::set_timestamps function for setting mtime/atime
X-Git-Tag: v4.6.2~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cd717a165bc8d05fa8c18ba641be878fcdc6fbf2;p=thirdparty%2Fccache.git

enhance: Add util::set_timestamps function for setting mtime/atime

(cherry picked from commit 176bdc0016b9f0bdbf23b111f135e3ff1931fdf7)
---

diff --git a/cmake/GenerateConfigurationFile.cmake b/cmake/GenerateConfigurationFile.cmake
index df909337f..f80258b0f 100644
--- a/cmake/GenerateConfigurationFile.cmake
+++ b/cmake/GenerateConfigurationFile.cmake
@@ -36,7 +36,8 @@ set(functions
     strndup
     syslog
     unsetenv
-    utimes)
+    utimensat
+)
 foreach(func IN ITEMS ${functions})
   string(TOUPPER ${func} func_var)
   set(func_var HAVE_${func_var})
diff --git a/cmake/config.h.in b/cmake/config.h.in
index 729a1d4af..bbc1397f5 100644
--- a/cmake/config.h.in
+++ b/cmake/config.h.in
@@ -172,8 +172,8 @@
 // Define if you have the "unsetenv" function.
 #cmakedefine HAVE_UNSETENV
 
-// Define if you have the "utimes" function.
-#cmakedefine HAVE_UTIMES
+// Define if you have the "utimensat" function.
+#cmakedefine HAVE_UTIMENSAT
 
 // Define if you have the "PTHREAD_MUTEX_ROBUST" constant.
 #cmakedefine HAVE_PTHREAD_MUTEX_ROBUST
diff --git a/src/ResultRetriever.cpp b/src/ResultRetriever.cpp
index fc2323be3..28a043c49 100644
--- a/src/ResultRetriever.cpp
+++ b/src/ResultRetriever.cpp
@@ -24,6 +24,7 @@
 
 #include <core/exceptions.hpp>
 #include <core/wincompat.hpp>
+#include <util/file.hpp>
 
 #include <fcntl.h>
 #include <sys/stat.h>
@@ -121,7 +122,7 @@ ResultRetriever::on_entry_start(uint8_t entry_number,
 
     // Update modification timestamp to save the file from LRU cleanup (and, if
     // hard-linked, to make the object file newer than the source file).
-    Util::update_mtime(*raw_file);
+    util::set_timestamps(*raw_file);
   } else {
     LOG("Writing to {}", dest_path);
     m_dest_fd = Fd(
diff --git a/src/Util.cpp b/src/Util.cpp
index 8898337f1..6bbab611d 100644
--- a/src/Util.cpp
+++ b/src/Util.cpp
@@ -64,12 +64,6 @@ extern "C" {
 #  include <sys/time.h>
 #endif
 
-#ifdef HAVE_UTIME_H
-#  include <utime.h>
-#elif defined(HAVE_SYS_UTIME_H)
-#  include <sys/utime.h>
-#endif
-
 #ifdef HAVE_LINUX_FS_H
 #  include <linux/magic.h>
 #  include <sys/statfs.h>
@@ -1500,16 +1494,6 @@ unsetenv(const std::string& name)
 #endif
 }
 
-void
-update_mtime(const std::string& path)
-{
-#ifdef HAVE_UTIMES
-  utimes(path.c_str(), nullptr);
-#else
-  utime(path.c_str(), nullptr);
-#endif
-}
-
 void
 wipe_path(const std::string& path)
 {
diff --git a/src/Util.hpp b/src/Util.hpp
index d0c58b869..092f9aaaf 100644
--- a/src/Util.hpp
+++ b/src/Util.hpp
@@ -405,9 +405,6 @@ bool unlink_tmp(const std::string& path,
 // Unset environment variable `name`.
 void unsetenv(const std::string& name);
 
-// Set mtime of `path` to the current timestamp.
-void update_mtime(const std::string& path);
-
 // Remove `path` (and its contents if it's a directory). A nonexistent path is
 // not considered an error.
 //
diff --git a/src/storage/primary/PrimaryStorage.cpp b/src/storage/primary/PrimaryStorage.cpp
index a4280b345..7ba213763 100644
--- a/src/storage/primary/PrimaryStorage.cpp
+++ b/src/storage/primary/PrimaryStorage.cpp
@@ -197,7 +197,7 @@ PrimaryStorage::get(const Digest& key, const core::CacheEntryType type) const
     "Retrieved {} from primary storage ({})", key.to_string(), cache_file.path);
 
   // Update modification timestamp to save file from LRU cleanup.
-  Util::update_mtime(cache_file.path);
+  util::set_timestamps(cache_file.path);
   return cache_file.path;
 }
 
@@ -311,7 +311,7 @@ PrimaryStorage::clean_internal_tempdir()
     return;
   }
 
-  Util::update_mtime(m_config.cache_dir());
+  util::set_timestamps(m_config.cache_dir());
 
   const std::string& temp_dir = m_config.temporary_dir();
   if (!Stat::lstat(temp_dir)) {
diff --git a/src/storage/secondary/FileStorage.cpp b/src/storage/secondary/FileStorage.cpp
index c824604cb..004084dc0 100644
--- a/src/storage/secondary/FileStorage.cpp
+++ b/src/storage/secondary/FileStorage.cpp
@@ -110,7 +110,7 @@ FileStorageBackend::get(const Digest& key)
   if (m_update_mtime) {
     // Update modification timestamp for potential LRU cleanup by some external
     // mechanism.
-    Util::update_mtime(path);
+    util::set_timestamps(path);
   }
 
   try {
diff --git a/src/util/file.cpp b/src/util/file.cpp
index 85c62c16a..722e2b28b 100644
--- a/src/util/file.cpp
+++ b/src/util/file.cpp
@@ -1,4 +1,4 @@
-// Copyright (C) 2021 Joel Rosdahl and other contributors
+// Copyright (C) 2021-2022 Joel Rosdahl and other contributors
 //
 // See doc/AUTHORS.adoc for a complete list of contributors.
 //
@@ -23,6 +23,18 @@
 #include <core/exceptions.hpp>
 #include <fmtmacros.hpp>
 
+#ifdef HAVE_UTIMENSAT
+#  include <fcntl.h>
+#  include <sys/stat.h>
+#else
+#  include <sys/types.h>
+#  ifdef HAVE_UTIME_H
+#    include <utime.h>
+#  elif defined(HAVE_SYS_UTIME_H)
+#    include <sys/utime.h>
+#  endif
+#endif
+
 namespace util {
 
 void
@@ -46,4 +58,27 @@ create_cachedir_tag(const std::string& dir)
   }
 }
 
+void
+set_timestamps(const std::string& path,
+               nonstd::optional<timespec> mtime,
+               nonstd::optional<timespec> atime)
+{
+#ifdef HAVE_UTIMENSAT
+  timespec atime_mtime[2];
+  if (mtime) {
+    atime_mtime[0] = atime ? *atime : *mtime;
+    atime_mtime[1] = *mtime;
+  }
+  const timespec* const timespecs = mtime ? atime_mtime : nullptr;
+  utimensat(AT_FDCWD, path.c_str(), timespecs, 0);
+#else
+  utimbuf atime_mtime;
+  if (mtime) {
+    atime_mtime.actime = atime ? atime->tv_sec : mtime->tv_sec;
+    atime_mtime.modtime = mtime->tv_sec;
+  }
+  utime(path.c_str(), &atime_mtime);
+#endif
+}
+
 } // namespace util
diff --git a/src/util/file.hpp b/src/util/file.hpp
index e0af9dd58..c1109f392 100644
--- a/src/util/file.hpp
+++ b/src/util/file.hpp
@@ -1,4 +1,4 @@
-// Copyright (C) 2021 Joel Rosdahl and other contributors
+// Copyright (C) 2021-2022 Joel Rosdahl and other contributors
 //
 // See doc/AUTHORS.adoc for a complete list of contributors.
 //
@@ -18,6 +18,8 @@
 
 #pragma once
 
+#include <third_party/nonstd/optional.hpp>
+
 #include <string>
 
 namespace util {
@@ -26,4 +28,10 @@ namespace util {
 
 void create_cachedir_tag(const std::string& dir);
 
+// Set atime/mtime of `path`. If `mtime` is nonstd::nullopt, set to the current
+// time. If `atime` is nonstd::nullopt, set to what `mtime` specifies.
+void set_timestamps(const std::string& path,
+                    nonstd::optional<timespec> mtime = nonstd::nullopt,
+                    nonstd::optional<timespec> atime = nonstd::nullopt);
+
 } // namespace util