1// Copyright 2009,2010 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// Darwin system calls.
6// This file is compiled as ordinary Go code,
7// but it is also input to mksyscall,
8// which parses the //sys lines and generates system call stubs.
9// Note that sometimes we use a lowercase //sys name and wrap
10// it in our own nicer implementation, either here or in
11// syscall_bsd.go or syscall_unix.go.
12
13package syscall
14
15import (
16	"internal/abi"
17	"unsafe"
18)
19
20func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
21func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
22func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
23func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
24
25var dupTrampoline = abi.FuncPCABI0(libc_dup2_trampoline)
26
27type SockaddrDatalink struct {
28	Len    uint8
29	Family uint8
30	Index  uint16
31	Type   uint8
32	Nlen   uint8
33	Alen   uint8
34	Slen   uint8
35	Data   [12]int8
36	raw    RawSockaddrDatalink
37}
38
39// Translate "kern.hostname" to []_C_int{0,1,2,3}.
40func nametomib(name string) (mib []_C_int, err error) {
41	const siz = unsafe.Sizeof(mib[0])
42
43	// NOTE(rsc): It seems strange to set the buffer to have
44	// size CTL_MAXNAME+2 but use only CTL_MAXNAME
45	// as the size. I don't know why the +2 is here, but the
46	// kernel uses +2 for its own implementation of this function.
47	// I am scared that if we don't include the +2 here, the kernel
48	// will silently write 2 words farther than we specify
49	// and we'll get memory corruption.
50	var buf [CTL_MAXNAME + 2]_C_int
51	n := uintptr(CTL_MAXNAME) * siz
52
53	p := (*byte)(unsafe.Pointer(&buf[0]))
54	bytes, err := ByteSliceFromString(name)
55	if err != nil {
56		return nil, err
57	}
58
59	// Magic sysctl: "setting" 0.3 to a string name
60	// lets you read back the array of integers form.
61	if err = sysctl([]_C_int{0, 3}, p, &n, &bytes[0], uintptr(len(name))); err != nil {
62		return nil, err
63	}
64	return buf[0 : n/siz], nil
65}
66
67func direntIno(buf []byte) (uint64, bool) {
68	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
69}
70
71func direntReclen(buf []byte) (uint64, bool) {
72	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
73}
74
75func direntNamlen(buf []byte) (uint64, bool) {
76	return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
77}
78
79func PtraceAttach(pid int) (err error) { return ptrace(PT_ATTACH, pid, 0, 0) }
80func PtraceDetach(pid int) (err error) { return ptrace(PT_DETACH, pid, 0, 0) }
81
82//sysnb pipe(p *[2]int32) (err error)
83
84func Pipe(p []int) (err error) {
85	if len(p) != 2 {
86		return EINVAL
87	}
88	var q [2]int32
89	err = pipe(&q)
90	if err == nil {
91		p[0] = int(q[0])
92		p[1] = int(q[1])
93	}
94	return
95}
96
97func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
98	var _p0 unsafe.Pointer
99	var bufsize uintptr
100	if len(buf) > 0 {
101		_p0 = unsafe.Pointer(&buf[0])
102		bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))
103	}
104	r0, _, e1 := syscall(abi.FuncPCABI0(libc_getfsstat_trampoline), uintptr(_p0), bufsize, uintptr(flags))
105	n = int(r0)
106	if e1 != 0 {
107		err = e1
108	}
109	return
110}
111
112func libc_getfsstat_trampoline()
113
114//go:cgo_import_dynamic libc_getfsstat getfsstat "/usr/lib/libSystem.B.dylib"
115
116// utimensat should be an internal detail,
117// but widely used packages access it using linkname.
118// Notable members of the hall of shame include:
119//   - github.com/tetratelabs/wazero
120//
121// See go.dev/issue/67401.
122//
123//go:linkname utimensat
124
125//sys	utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)
126
127/*
128 * Wrapped
129 */
130
131//sys	kill(pid int, signum int, posix int) (err error)
132
133func Kill(pid int, signum Signal) (err error) { return kill(pid, int(signum), 1) }
134
135/*
136 * Exposed directly
137 */
138//sys	Access(path string, mode uint32) (err error)
139//sys	Adjtime(delta *Timeval, olddelta *Timeval) (err error)
140//sys	Chdir(path string) (err error)
141//sys	Chflags(path string, flags int) (err error)
142//sys	Chmod(path string, mode uint32) (err error)
143//sys	Chown(path string, uid int, gid int) (err error)
144//sys	Chroot(path string) (err error)
145//sys	Close(fd int) (err error)
146//sys	closedir(dir uintptr) (err error)
147//sys	Dup(fd int) (nfd int, err error)
148//sys	Dup2(from int, to int) (err error)
149//sys	Exchangedata(path1 string, path2 string, options int) (err error)
150//sys	Fchdir(fd int) (err error)
151//sys	Fchflags(fd int, flags int) (err error)
152//sys	Fchmod(fd int, mode uint32) (err error)
153//sys	Fchown(fd int, uid int, gid int) (err error)
154//sys	Flock(fd int, how int) (err error)
155//sys	Fpathconf(fd int, name int) (val int, err error)
156//sys	Fsync(fd int) (err error)
157//  Fsync is not called for os.File.Sync(). Please see internal/poll/fd_fsync_darwin.go
158//sys	Ftruncate(fd int, length int64) (err error)
159//sys	Getdtablesize() (size int)
160//sysnb	Getegid() (egid int)
161//sysnb	Geteuid() (uid int)
162//sysnb	Getgid() (gid int)
163//sysnb	Getpgid(pid int) (pgid int, err error)
164//sysnb	Getpgrp() (pgrp int)
165//sysnb	Getpid() (pid int)
166//sysnb	Getppid() (ppid int)
167//sys	Getpriority(which int, who int) (prio int, err error)
168//sysnb	Getrlimit(which int, lim *Rlimit) (err error)
169//sysnb	Getrusage(who int, rusage *Rusage) (err error)
170//sysnb	Getsid(pid int) (sid int, err error)
171//sysnb	Getuid() (uid int)
172//sysnb	Issetugid() (tainted bool)
173//sys	Kqueue() (fd int, err error)
174//sys	Lchown(path string, uid int, gid int) (err error)
175//sys	Link(path string, link string) (err error)
176//sys	Listen(s int, backlog int) (err error)
177//sys	Mkdir(path string, mode uint32) (err error)
178//sys	Mkfifo(path string, mode uint32) (err error)
179//sys	Mknod(path string, mode uint32, dev int) (err error)
180//sys	Mlock(b []byte) (err error)
181//sys	Mlockall(flags int) (err error)
182//sys	Mprotect(b []byte, prot int) (err error)
183//sys	msync(b []byte, flags int) (err error)
184//sys	Munlock(b []byte) (err error)
185//sys	Munlockall() (err error)
186//sys	Open(path string, mode int, perm uint32) (fd int, err error)
187//sys	Pathconf(path string, name int) (val int, err error)
188//sys	pread(fd int, p []byte, offset int64) (n int, err error)
189//sys	pwrite(fd int, p []byte, offset int64) (n int, err error)
190//sys	read(fd int, p []byte) (n int, err error)
191//sys	readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno)
192//sys	Readlink(path string, buf []byte) (n int, err error)
193//sys	Rename(from string, to string) (err error)
194//sys	Revoke(path string) (err error)
195//sys	Rmdir(path string) (err error)
196//sys	Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_lseek
197//sys	Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
198//sys	Setegid(egid int) (err error)
199//sysnb	Seteuid(euid int) (err error)
200//sysnb	Setgid(gid int) (err error)
201//sys	Setlogin(name string) (err error)
202//sysnb	Setpgid(pid int, pgid int) (err error)
203//sys	Setpriority(which int, who int, prio int) (err error)
204//sys	Setprivexec(flag int) (err error)
205//sysnb	Setregid(rgid int, egid int) (err error)
206//sysnb	Setreuid(ruid int, euid int) (err error)
207//sysnb	setrlimit(which int, lim *Rlimit) (err error)
208//sysnb	Setsid() (pid int, err error)
209//sysnb	Settimeofday(tp *Timeval) (err error)
210//sysnb	Setuid(uid int) (err error)
211//sys	Symlink(path string, link string) (err error)
212//sys	Sync() (err error)
213//sys	Truncate(path string, length int64) (err error)
214//sys	Umask(newmask int) (oldmask int)
215//sys	Undelete(path string) (err error)
216//sys	Unlink(path string) (err error)
217//sys	Unmount(path string, flags int) (err error)
218//sys	write(fd int, p []byte) (n int, err error)
219//sys	writev(fd int, iovecs []Iovec) (cnt uintptr, err error)
220//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
221//sys   munmap(addr uintptr, length uintptr) (err error)
222//sysnb fork() (pid int, err error)
223//sysnb execve(path *byte, argv **byte, envp **byte) (err error)
224//sysnb exit(res int) (err error)
225//sys	sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error)
226//sys   unlinkat(fd int, path string, flags int) (err error)
227//sys   openat(fd int, path string, flags int, perm uint32) (fdret int, err error)
228//sys	getcwd(buf []byte) (n int, err error)
229
230func init() {
231	execveDarwin = execve
232}
233
234func fdopendir(fd int) (dir uintptr, err error) {
235	r0, _, e1 := syscallPtr(abi.FuncPCABI0(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
236	dir = r0
237	if e1 != 0 {
238		err = errnoErr(e1)
239	}
240	return
241}
242
243func libc_fdopendir_trampoline()
244
245//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
246
247func readlen(fd int, buf *byte, nbuf int) (n int, err error) {
248	r0, _, e1 := syscall(abi.FuncPCABI0(libc_read_trampoline), uintptr(fd), uintptr(unsafe.Pointer(buf)), uintptr(nbuf))
249	n = int(r0)
250	if e1 != 0 {
251		err = errnoErr(e1)
252	}
253	return
254}
255
256func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
257	// Simulate Getdirentries using fdopendir/readdir_r/closedir.
258	// We store the number of entries to skip in the seek
259	// offset of fd. See issue #31368.
260	// It's not the full required semantics, but should handle the case
261	// of calling Getdirentries or ReadDirent repeatedly.
262	// It won't handle assigning the results of lseek to *basep, or handle
263	// the directory being edited underfoot.
264	skip, err := Seek(fd, 0, 1 /* SEEK_CUR */)
265	if err != nil {
266		return 0, err
267	}
268
269	// We need to duplicate the incoming file descriptor
270	// because the caller expects to retain control of it, but
271	// fdopendir expects to take control of its argument.
272	// Just Dup'ing the file descriptor is not enough, as the
273	// result shares underlying state. Use openat to make a really
274	// new file descriptor referring to the same directory.
275	fd2, err := openat(fd, ".", O_RDONLY, 0)
276	if err != nil {
277		return 0, err
278	}
279	d, err := fdopendir(fd2)
280	if err != nil {
281		Close(fd2)
282		return 0, err
283	}
284	defer closedir(d)
285
286	var cnt int64
287	for {
288		var entry Dirent
289		var entryp *Dirent
290		e := readdir_r(d, &entry, &entryp)
291		if e != 0 {
292			return n, errnoErr(e)
293		}
294		if entryp == nil {
295			break
296		}
297		if skip > 0 {
298			skip--
299			cnt++
300			continue
301		}
302		reclen := int(entry.Reclen)
303		if reclen > len(buf) {
304			// Not enough room. Return for now.
305			// The counter will let us know where we should start up again.
306			// Note: this strategy for suspending in the middle and
307			// restarting is O(n^2) in the length of the directory. Oh well.
308			break
309		}
310		// Copy entry into return buffer.
311		copy(buf, unsafe.Slice((*byte)(unsafe.Pointer(&entry)), reclen))
312		buf = buf[reclen:]
313		n += reclen
314		cnt++
315	}
316	// Set the seek offset of the input fd to record
317	// how many files we've already returned.
318	_, err = Seek(fd, cnt, 0 /* SEEK_SET */)
319	if err != nil {
320		return n, err
321	}
322
323	return n, nil
324}
325
326// Implemented in the runtime package (runtime/sys_darwin.go)
327func syscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
328func syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
329func syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
330func rawSyscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
331func rawSyscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
332func syscallPtr(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
333