Implement sys::fs::copy_file using the macOS copyfile(3) API
to support APFS clones.
This patch adds a Darwin-specific implementation of
llvm::sys::fs::copy_file() that uses the macOS copyfile(3) API to
support APFS copy-on-write clones, which should be faster and much
more space efficient.
https://developer.apple.com/library/archive/documentation/FileManagement/Conceptual/APFS_Guide/ToolsandAPIs/ToolsandAPIs.html
Differential Revision: https://reviews.llvm.org/D60802
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358628 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Path.cpp b/lib/Support/Path.cpp
index 902df74..9466591 100644
--- a/lib/Support/Path.cpp
+++ b/lib/Support/Path.cpp
@@ -935,6 +935,7 @@
return create_directory(P, IgnoreExisting, Perms);
}
+#ifndef __APPLE__
static std::error_code copy_file_internal(int ReadFD, int WriteFD) {
const size_t BufSize = 4096;
char *Buf = new char[BufSize];
@@ -988,6 +989,7 @@
return EC;
}
+#endif
ErrorOr<MD5::MD5Result> md5_contents(int FD) {
MD5 Hash;
diff --git a/lib/Support/Unix/Path.inc b/lib/Support/Unix/Path.inc
index 05ccc6c..27db41a 100644
--- a/lib/Support/Unix/Path.inc
+++ b/lib/Support/Unix/Path.inc
@@ -37,6 +37,7 @@
#ifdef __APPLE__
#include <mach-o/dyld.h>
#include <sys/attr.h>
+#include <copyfile.h>
#elif defined(__DragonFly__)
#include <sys/mount.h>
#endif
@@ -1113,5 +1114,55 @@
} // end namespace path
+namespace fs {
+
+#ifdef __APPLE__
+/// This implementation tries to perform an APFS CoW clone of the file,
+/// which can be much faster and uses less space.
+std::error_code copy_file(const Twine &From, const Twine &To) {
+ uint32_t Flag = COPYFILE_DATA;
+ bool IsSymlink;
+ if (std::error_code Error = is_symlink_file(From, IsSymlink))
+ return Error;
+
+ if (!IsSymlink)
+ if (__builtin_available(macos 10.12, *))
+ Flag = COPYFILE_CLONE;
+
+ int Status =
+ copyfile(From.str().c_str(), To.str().c_str(), /* State */ NULL, Flag);
+
+ if (Status == 0)
+ return std::error_code();
+ return std::error_code(errno, std::generic_category());
+}
+
+/// This implementation tries to perform an APFS CoW clone of the file,
+/// which can be much faster and uses less space.
+std::error_code copy_file(const Twine &From, int ToFD) {
+ uint32_t Flag = COPYFILE_DATA;
+ bool IsSymlink;
+ if (std::error_code Error = is_symlink_file(From, IsSymlink))
+ return Error;
+
+ int ReadFD;
+ if (std::error_code EC = openFileForRead(From, ReadFD, OF_None))
+ return EC;
+
+ if (!IsSymlink)
+ if (__builtin_available(macos 10.12, *))
+ Flag = COPYFILE_CLONE;
+
+ int Status = fcopyfile(ReadFD, ToFD, /*State*/ NULL, Flag);
+
+ close(ReadFD);
+ if (Status == 0)
+ return std::error_code();
+ return std::error_code(errno, std::generic_category());
+}
+#endif
+
+} // end namespace fs
+
} // end namespace sys
} // end namespace llvm
