From 5a56810603ff9608c98d71cbfb8a6454da4c2261 Mon Sep 17 00:00:00 2001 From: Sebastian Lackner Date: Tue, 28 Nov 2017 00:54:38 +0100 Subject: fusefrontend: Use the Symlinkat syscall for longname handling --- internal/syscallcompat/sys_darwin.go | 17 +++++++++++++++++ internal/syscallcompat/sys_linux.go | 21 +++++++++++++++++++++ 2 files changed, 38 insertions(+) (limited to 'internal/syscallcompat') diff --git a/internal/syscallcompat/sys_darwin.go b/internal/syscallcompat/sys_darwin.go index 5504860..4068e1a 100644 --- a/internal/syscallcompat/sys_darwin.go +++ b/internal/syscallcompat/sys_darwin.go @@ -148,3 +148,20 @@ func Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error) { defer syscall.Fchdir(cwd) return syscall.Lchown(path, uid, gid) } + +// Poor man's Symlinkat. +func Symlinkat(oldpath string, newdirfd int, newpath string) (err error) { + chdirMutex.Lock() + defer chdirMutex.Unlock() + cwd, err := syscall.Open(".", syscall.O_RDONLY, 0) + if err != nil { + return err + } + defer syscall.Close(cwd) + err = syscall.Fchdir(newdirfd) + if err != nil { + return err + } + defer syscall.Fchdir(cwd) + return syscall.Symlink(oldpath, newpath) +} diff --git a/internal/syscallcompat/sys_linux.go b/internal/syscallcompat/sys_linux.go index 8a64a81..277015e 100644 --- a/internal/syscallcompat/sys_linux.go +++ b/internal/syscallcompat/sys_linux.go @@ -4,6 +4,7 @@ package syscallcompat import ( "sync" "syscall" + "unsafe" "github.com/rfjakob/gocryptfs/internal/tlog" ) @@ -73,3 +74,23 @@ func Dup3(oldfd int, newfd int, flags int) (err error) { func Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error) { return syscall.Fchownat(dirfd, path, uid, gid, flags) } + +// Symlinkat syscall. Unfortunately this function is not exported directly, so +// manually call it by using the corresponding syscall number. +func Symlinkat(oldpath string, newdirfd int, newpath string) (err error) { + var _p0 *byte + _p0, err = syscall.BytePtrFromString(oldpath) + if err != nil { + return + } + var _p1 *byte + _p1, err = syscall.BytePtrFromString(newpath) + if err != nil { + return + } + _, _, e1 := syscall.Syscall(syscall.SYS_SYMLINKAT, uintptr(unsafe.Pointer(_p0)), uintptr(newdirfd), uintptr(unsafe.Pointer(_p1))) + if e1 != 0 { + err = e1 + } + return +} -- cgit v1.2.3