darwin: replace custom syscall package with Go native syscall package

This required a few compiler and runtime tricks to work, but I ran a
bunch of tests and it seems fine. (CI will of course do more exhaustive
testing).

The main benefit here is that we don't need to maintain the darwin
version of the syscall package, and reduce extra risks for bugs (because
we reuse the well-tested syscall package). For example, Go 1.23 needed a
bunch of new constants in the syscall package. That would have been
avoided if we had used the native syscall package on MacOS.

7 files changed, 4 insertions, 516 deletions

diff --git a/src/syscall/env_libc.go b/src/syscall/env_libc.go
index f558901cf..4ad078dc5 100644
--- a/src/syscall/env_libc.go
+++ b/src/syscall/env_libc.go
@@ -1,4 +1,4 @@
-//go:build darwin || nintendoswitch || wasip1
+//go:build nintendoswitch || wasip1
 
 package syscall
 
diff --git a/src/syscall/errno_other.go b/src/syscall/errno_other.go
index b988fbc1e..3a06ac018 100644
--- a/src/syscall/errno_other.go
+++ b/src/syscall/errno_other.go
@@ -1,4 +1,4 @@
-//go:build !wasip1 && !wasip2 && !darwin
+//go:build !wasip1 && !wasip2
 
 package syscall
 
diff --git a/src/syscall/mmap_unix_test.go b/src/syscall/mmap_unix_test.go
index 1946265d8..62748a939 100644
--- a/src/syscall/mmap_unix_test.go
+++ b/src/syscall/mmap_unix_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build darwin || linux
+//go:build linux
 
 package syscall_test
 
diff --git a/src/syscall/syscall_libc.go b/src/syscall/syscall_libc.go
index 2321292d9..67cf6681f 100644
--- a/src/syscall/syscall_libc.go
+++ b/src/syscall/syscall_libc.go
@@ -1,4 +1,4 @@
-//go:build darwin || nintendoswitch || wasip1 || wasip2
+//go:build nintendoswitch || wasip1 || wasip2
 
 package syscall
 
diff --git a/src/syscall/syscall_libc_darwin.go b/src/syscall/syscall_libc_darwin.go
deleted file mode 100644
index 3b0341880..000000000
--- a/src/syscall/syscall_libc_darwin.go
+++ /dev/null
@@ -1,432 +0,0 @@
-//go:build darwin
-
-package syscall
-
-import (
-	"internal/itoa"
-	"unsafe"
-)
-
-// This file defines errno and constants to match the darwin libsystem ABI.
-// Values have been copied from src/syscall/zerrors_darwin_amd64.go.
-
-// This function returns the error location in the darwin ABI.
-// Discovered by compiling the following code using Clang:
-//
-//	#include <errno.h>
-//	int getErrno() {
-//	    return errno;
-//	}
-//
-//export __error
-func libc___error() *int32
-
-// getErrno returns the current C errno. It may not have been caused by the last
-// call, so it should only be relied upon when the last call indicates an error
-// (for example, by returning -1).
-func getErrno() Errno {
-	errptr := libc___error()
-	return Errno(uintptr(*errptr))
-}
-
-func (e Errno) Is(target error) bool {
-	switch target.Error() {
-	case "permission denied":
-		return e == EACCES || e == EPERM
-	case "file already exists":
-		return e == EEXIST
-	case "file does not exist":
-		return e == ENOENT
-	}
-	return false
-}
-
-// Source: upstream zerrors_darwin_amd64.go
-const (
-	DT_BLK     = 0x6
-	DT_CHR     = 0x2
-	DT_DIR     = 0x4
-	DT_FIFO    = 0x1
-	DT_LNK     = 0xa
-	DT_REG     = 0x8
-	DT_SOCK    = 0xc
-	DT_UNKNOWN = 0x0
-	DT_WHT     = 0xe
-	F_GETFL    = 0x3
-	F_SETFL    = 0x4
-	O_NONBLOCK = 0x4
-	TIOCSPGRP  = 0x80047476
-)
-
-// Source: https://opensource.apple.com/source/xnu/xnu-7195.141.2/bsd/sys/errno.h.auto.html
-const (
-	EPERM           Errno = 1
-	ENOENT          Errno = 2
-	ESRCH           Errno = 3
-	EINTR           Errno = 4
-	EIO             Errno = 5
-	ENXIO           Errno = 6
-	E2BIG           Errno = 7
-	ENOEXEC         Errno = 8
-	EBADF           Errno = 9
-	ECHILD          Errno = 10
-	EDEADLK         Errno = 11
-	ENOMEM          Errno = 12
-	EACCES          Errno = 13
-	EFAULT          Errno = 14
-	ENOTBLK         Errno = 15
-	EBUSY           Errno = 16
-	EEXIST          Errno = 17
-	EXDEV           Errno = 18
-	ENODEV          Errno = 19
-	ENOTDIR         Errno = 20
-	EISDIR          Errno = 21
-	EINVAL          Errno = 22
-	ENFILE          Errno = 23
-	EMFILE          Errno = 24
-	ENOTTY          Errno = 25
-	ETXTBSY         Errno = 26
-	EFBIG           Errno = 27
-	ENOSPC          Errno = 28
-	ESPIPE          Errno = 29
-	EROFS           Errno = 30
-	EMLINK          Errno = 31
-	EPIPE           Errno = 32
-	EDOM            Errno = 33
-	ERANGE          Errno = 34
-	EAGAIN          Errno = 35
-	EWOULDBLOCK     Errno = EAGAIN
-	EINPROGRESS     Errno = 36
-	EALREADY        Errno = 37
-	ENOTSOCK        Errno = 38
-	EDESTADDRREQ    Errno = 39
-	EMSGSIZE        Errno = 40
-	EPROTOTYPE      Errno = 41
-	ENOPROTOOPT     Errno = 42
-	EPROTONOSUPPORT Errno = 43
-	ESOCKTNOSUPPORT Errno = 44
-	ENOTSUP         Errno = 45
-	EPFNOSUPPORT    Errno = 46
-	EAFNOSUPPORT    Errno = 47
-	EADDRINUSE      Errno = 48
-	EADDRNOTAVAIL   Errno = 49
-	ENETDOWN        Errno = 50
-	ENETUNREACH     Errno = 51
-	ENETRESET       Errno = 52
-	ECONNABORTED    Errno = 53
-	ECONNRESET      Errno = 54
-	ENOBUFS         Errno = 55
-	EISCONN         Errno = 56
-	ENOTCONN        Errno = 57
-	ESHUTDOWN       Errno = 58
-	ETOOMANYREFS    Errno = 59
-	ETIMEDOUT       Errno = 60
-	ECONNREFUSED    Errno = 61
-	ELOOP           Errno = 62
-	ENAMETOOLONG    Errno = 63
-	EHOSTDOWN       Errno = 64
-	EHOSTUNREACH    Errno = 65
-	ENOTEMPTY       Errno = 66
-	EPROCLIM        Errno = 67
-	EUSERS          Errno = 68
-	EDQUOT          Errno = 69
-	ESTALE          Errno = 70
-	EREMOTE         Errno = 71
-	EBADRPC         Errno = 72
-	ERPCMISMATCH    Errno = 73
-	EPROGUNAVAIL    Errno = 74
-	EPROGMISMATCH   Errno = 75
-	EPROCUNAVAIL    Errno = 76
-	ENOLCK          Errno = 77
-	ENOSYS          Errno = 78
-	EFTYPE          Errno = 79
-	EAUTH           Errno = 80
-	ENEEDAUTH       Errno = 81
-	EPWROFF         Errno = 82
-	EDEVERR         Errno = 83
-	EOVERFLOW       Errno = 84
-	EBADEXEC        Errno = 85
-	EBADARCH        Errno = 86
-	ESHLIBVERS      Errno = 87
-	EBADMACHO       Errno = 88
-	ECANCELED       Errno = 89
-	EIDRM           Errno = 90
-	ENOMSG          Errno = 91
-	EILSEQ          Errno = 92
-	ENOATTR         Errno = 93
-	EBADMSG         Errno = 94
-	EMULTIHOP       Errno = 95
-	ENODATA         Errno = 96
-	ENOLINK         Errno = 97
-	ENOSR           Errno = 98
-	ENOSTR          Errno = 99
-	EPROTO          Errno = 100
-	ETIME           Errno = 101
-	EOPNOTSUPP      Errno = 102
-	ENOPOLICY       Errno = 103
-	ENOTRECOVERABLE Errno = 104
-	EOWNERDEAD      Errno = 105
-	EQFULL          Errno = 106
-	ELAST           Errno = 106
-)
-
-type Signal int
-
-// Source: https://opensource.apple.com/source/xnu/xnu-7195.81.3/bsd/sys/signal.h
-const (
-	SIGINT  Signal = 2  /* interrupt */
-	SIGQUIT Signal = 3  /* quit */
-	SIGILL  Signal = 4  /* illegal instruction (not reset when caught) */
-	SIGTRAP Signal = 5  /* trace trap (not reset when caught) */
-	SIGABRT Signal = 6  /* abort() */
-	SIGFPE  Signal = 8  /* floating point exception */
-	SIGKILL Signal = 9  /* kill (cannot be caught or ignored) */
-	SIGBUS  Signal = 10 /* bus error */
-	SIGSEGV Signal = 11 /* segmentation violation */
-	SIGPIPE Signal = 13 /* write on a pipe with no one to read it */
-	SIGTERM Signal = 15 /* software termination signal from kill */
-	SIGCHLD Signal = 20 /* to parent on child stop or exit */
-)
-
-func (s Signal) Signal() {}
-
-func (s Signal) String() string {
-	if 0 <= s && int(s) < len(signals) {
-		str := signals[s]
-		if str != "" {
-			return str
-		}
-	}
-	return "signal " + itoa.Itoa(int(s))
-}
-
-var signals = [...]string{}
-
-const (
-	Stdin  = 0
-	Stdout = 1
-	Stderr = 2
-)
-
-const (
-	O_RDONLY = 0x0
-	O_WRONLY = 0x1
-	O_RDWR   = 0x2
-	O_APPEND = 0x8
-	O_SYNC   = 0x80
-	O_CREAT  = 0x200
-	O_TRUNC  = 0x400
-	O_EXCL   = 0x800
-
-	O_CLOEXEC = 0x01000000
-)
-
-// Source: https://opensource.apple.com/source/xnu/xnu-7195.81.3/bsd/sys/mman.h.auto.html
-const (
-	PROT_NONE  = 0x00 // no permissions
-	PROT_READ  = 0x01 // pages can be read
-	PROT_WRITE = 0x02 // pages can be written
-	PROT_EXEC  = 0x04 // pages can be executed
-
-	MAP_SHARED  = 0x0001 // share changes
-	MAP_PRIVATE = 0x0002 // changes are private
-
-	MAP_FILE      = 0x0000 // map from file (default)
-	MAP_ANON      = 0x1000 // allocated from memory, swap space
-	MAP_ANONYMOUS = MAP_ANON
-)
-
-type Timespec struct {
-	Sec  int64
-	Nsec int64
-}
-
-// Unix returns the time stored in ts as seconds plus nanoseconds.
-func (ts *Timespec) Unix() (sec int64, nsec int64) {
-	return int64(ts.Sec), int64(ts.Nsec)
-}
-
-// Source: upstream ztypes_darwin_amd64.go
-type Dirent struct {
-	Ino       uint64
-	Seekoff   uint64
-	Reclen    uint16
-	Namlen    uint16
-	Type      uint8
-	Name      [1024]int8
-	Pad_cgo_0 [3]byte
-}
-
-type Stat_t struct {
-	Dev       int32
-	Mode      uint16
-	Nlink     uint16
-	Ino       uint64
-	Uid       uint32
-	Gid       uint32
-	Rdev      int32
-	Pad_cgo_0 [4]byte
-	Atimespec Timespec
-	Mtimespec Timespec
-	Ctimespec Timespec
-	Btimespec Timespec
-	Size      int64
-	Blocks    int64
-	Blksize   int32
-	Flags     uint32
-	Gen       uint32
-	Lspare    int32
-	Qspare    [2]int64
-}
-
-// Source: https://github.com/apple/darwin-xnu/blob/main/bsd/sys/_types/_s_ifmt.h
-const (
-	S_IEXEC  = 0x40
-	S_IFBLK  = 0x6000
-	S_IFCHR  = 0x2000
-	S_IFDIR  = 0x4000
-	S_IFIFO  = 0x1000
-	S_IFLNK  = 0xa000
-	S_IFMT   = 0xf000
-	S_IFREG  = 0x8000
-	S_IFSOCK = 0xc000
-	S_IFWHT  = 0xe000
-	S_IREAD  = 0x100
-	S_IRGRP  = 0x20
-	S_IROTH  = 0x4
-	S_IRUSR  = 0x100
-	S_IRWXG  = 0x38
-	S_IRWXO  = 0x7
-	S_IRWXU  = 0x1c0
-	S_ISGID  = 0x400
-	S_ISTXT  = 0x200
-	S_ISUID  = 0x800
-	S_ISVTX  = 0x200
-	S_IWGRP  = 0x10
-	S_IWOTH  = 0x2
-	S_IWRITE = 0x80
-	S_IWUSR  = 0x80
-	S_IXGRP  = 0x8
-	S_IXOTH  = 0x1
-	S_IXUSR  = 0x40
-)
-
-func Stat(path string, p *Stat_t) (err error) {
-	data := cstring(path)
-	n := libc_stat(&data[0], unsafe.Pointer(p))
-
-	if n < 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func Fstat(fd int, p *Stat_t) (err error) {
-	n := libc_fstat(int32(fd), unsafe.Pointer(p))
-
-	if n < 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func Lstat(path string, p *Stat_t) (err error) {
-	data := cstring(path)
-	n := libc_lstat(&data[0], unsafe.Pointer(p))
-	if n < 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func Fdopendir(fd int) (dir uintptr, err error) {
-	r0 := libc_fdopendir(int32(fd))
-	dir = uintptr(r0)
-	if dir == 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func Pipe2(fds []int, flags int) (err error) {
-	// Mac only has Pipe, which ignores the flags argument
-	buf := make([]int32, 2)
-	fail := int(libc_pipe(&buf[0]))
-	if fail < 0 {
-		err = getErrno()
-	} else {
-		fds[0] = int(buf[0])
-		fds[1] = int(buf[1])
-	}
-	return
-}
-
-func Chmod(path string, mode uint32) (err error) {
-	data := cstring(path)
-	fail := int(libc_chmod(&data[0], mode))
-	if fail < 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func closedir(dir uintptr) (err error) {
-	e := libc_closedir(unsafe.Pointer(dir))
-	if e != 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (err error) {
-	e1 := libc_readdir_r(unsafe.Pointer(dir), unsafe.Pointer(entry), unsafe.Pointer(result))
-	if e1 != 0 {
-		err = getErrno()
-	}
-	return
-}
-
-func Getpagesize() int {
-	return int(libc_getpagesize())
-}
-
-// The following RawSockAddr* types have been copied from the Go source tree and
-// are here purely to fix build errors.
-
-type RawSockaddr struct {
-	Len    uint8
-	Family uint8
-	Data   [14]int8
-}
-
-type RawSockaddrInet4 struct {
-	Len    uint8
-	Family uint8
-	Port   uint16
-	Addr   [4]byte /* in_addr */
-	Zero   [8]int8
-}
-
-type RawSockaddrInet6 struct {
-	Len      uint8
-	Family   uint8
-	Port     uint16
-	Flowinfo uint32
-	Addr     [16]byte /* in6_addr */
-	Scope_id uint32
-}
-
-// int pipe(int32 *fds);
-//
-//export pipe
-func libc_pipe(fds *int32) int32
-
-// int getpagesize();
-//
-//export getpagesize
-func libc_getpagesize() int32
-
-// int open(const char *pathname, int flags, mode_t mode);
-//
-//export syscall_libc_open
-func libc_open(pathname *byte, flags int32, mode uint32) int32
diff --git a/src/syscall/syscall_libc_darwin_amd64.go b/src/syscall/syscall_libc_darwin_amd64.go
deleted file mode 100644
index 1f5528ec5..000000000
--- a/src/syscall/syscall_libc_darwin_amd64.go
+++ /dev/null
@@ -1,43 +0,0 @@
-//go:build darwin
-
-package syscall
-
-import (
-	"unsafe"
-)
-
-// The odd $INODE64 suffix is an Apple compatibility feature, see
-// __DARWIN_INODE64 in /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/sys/cdefs.h
-// and https://assert.cc/posts/darwin_use_64_bit_inode_vs_ctypes/
-// Without it, you get the old, smaller struct stat from mac os 10.2 or so.
-// It not needed on arm64.
-
-// struct DIR * buf fdopendir(int fd);
-//
-//export fdopendir$INODE64
-func libc_fdopendir(fd int32) unsafe.Pointer
-
-// int closedir(struct DIR * buf);
-//
-//export closedir
-func libc_closedir(unsafe.Pointer) int32
-
-// int readdir_r(struct DIR * buf, struct dirent *entry, struct dirent **result);
-//
-//export readdir_r$INODE64
-func libc_readdir_r(unsafe.Pointer, unsafe.Pointer, unsafe.Pointer) int32
-
-// int stat(const char *path, struct stat * buf);
-//
-//export stat$INODE64
-func libc_stat(pathname *byte, ptr unsafe.Pointer) int32
-
-// int fstat(int fd, struct stat * buf);
-//
-//export fstat$INODE64
-func libc_fstat(fd int32, ptr unsafe.Pointer) int32
-
-// int lstat(const char *path, struct stat * buf);
-//
-//export lstat$INODE64
-func libc_lstat(pathname *byte, ptr unsafe.Pointer) int32
diff --git a/src/syscall/syscall_libc_darwin_arm64.go b/src/syscall/syscall_libc_darwin_arm64.go
deleted file mode 100644
index f9ce3c4e3..000000000
--- a/src/syscall/syscall_libc_darwin_arm64.go
+++ /dev/null
@@ -1,37 +0,0 @@
-//go:build darwin
-
-package syscall
-
-import (
-	"unsafe"
-)
-
-// struct DIR * buf fdopendir(int fd);
-//
-//export fdopendir
-func libc_fdopendir(fd int32) unsafe.Pointer
-
-// int closedir(struct DIR * buf);
-//
-//export closedir
-func libc_closedir(unsafe.Pointer) int32
-
-// int readdir_r(struct DIR * buf, struct dirent *entry, struct dirent **result);
-//
-//export readdir_r
-func libc_readdir_r(unsafe.Pointer, unsafe.Pointer, unsafe.Pointer) int32
-
-// int stat(const char *path, struct stat * buf);
-//
-//export stat
-func libc_stat(pathname *byte, ptr unsafe.Pointer) int32
-
-// int fstat(int fd, struct stat * buf);
-//
-//export fstat
-func libc_fstat(fd int32, ptr unsafe.Pointer) int32
-
-// int lstat(const char *path, struct stat * buf);
-//
-//export lstat
-func libc_lstat(pathname *byte, ptr unsafe.Pointer) int32