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madsmtmmadsmtm
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Change the syntax of the internal weak! macro
Change the syntax to include parameter names and a trailing semicolon. Motivation: - Mirror the `syscall!` macro. - Allow rustfmt to format it (when wrapped in parentheses). - For better documentation (having the parameter names available in the source code is a bit nicer). - Allow future improvements to this macro where we can sometimes use the symbol directly when it's statically known to be available.
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9 files changed

+144
-80
lines changed

9 files changed

+144
-80
lines changed

‎std/src/sys/fs/unix.rs‎

Lines changed: 10 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -155,15 +155,15 @@ cfg_has_statx! {{
155155
enum STATX_STATE{ Unknown = 0, Present, Unavailable }
156156
static STATX_SAVED_STATE: AtomicU8 = AtomicU8::new(STATX_STATE::Unknown as u8);
157157

158-
syscall! {
158+
syscall!(
159159
fn statx(
160160
fd: c_int,
161161
pathname: *const c_char,
162162
flags: c_int,
163163
mask: libc::c_uint,
164-
statxbuf: *mut libc::statx
165-
) -> c_int
166-
}
164+
statxbuf: *mut libc::statx,
165+
) -> c_int;
166+
);
167167

168168
let statx_availability = STATX_SAVED_STATE.load(Ordering::Relaxed);
169169
if statx_availability == STATX_STATE::Unavailable as u8 {
@@ -1540,7 +1540,9 @@ impl File {
15401540
let times = [to_timespec(times.accessed)?, to_timespec(times.modified)?];
15411541
// futimens requires Android API level 19
15421542
cvt(unsafe {
1543-
weak!(fn futimens(c_int, *const libc::timespec) -> c_int);
1543+
weak!(
1544+
fn futimens(fd: c_int, times: *const libc::timespec) -> c_int;
1545+
);
15441546
match futimens.get() {
15451547
Some(futimens) => futimens(self.as_raw_fd(), times.as_ptr()),
15461548
None => return Err(io::const_error!(
@@ -1556,7 +1558,9 @@ impl File {
15561558
use crate::sys::{time::__timespec64, weak::weak};
15571559

15581560
// Added in glibc 2.34
1559-
weak!(fn __futimens64(libc::c_int, *const __timespec64) -> libc::c_int);
1561+
weak!(
1562+
fn __futimens64(fd: c_int, times: *const __timespec64) -> c_int;
1563+
);
15601564

15611565
if let Some(futimens64) = __futimens64.get() {
15621566
let to_timespec = |time: Option<SystemTime>| time.map(|time| time.t.to_timespec64())

‎std/src/sys/pal/unix/fd.rs‎

Lines changed: 40 additions & 12 deletions
Original file line numberDiff line numberDiff line change
@@ -232,14 +232,14 @@ impl FileDesc {
232232
// implementation if `preadv` is not available.
233233
#[cfg(all(target_os = "android", target_pointer_width = "64"))]
234234
pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
235-
super::weak::syscall! {
235+
super::weak::syscall!(
236236
fn preadv(
237237
fd: libc::c_int,
238238
iovec: *const libc::iovec,
239239
n_iovec: libc::c_int,
240-
offset: off64_t
241-
) -> isize
242-
}
240+
offset: off64_t,
241+
) -> isize;
242+
);
243243

244244
let ret = cvt(unsafe {
245245
preadv(
@@ -257,7 +257,14 @@ impl FileDesc {
257257
// and its metadata from LLVM IR.
258258
#[no_sanitize(cfi)]
259259
pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
260-
super::weak::weak!(fn preadv64(libc::c_int, *const libc::iovec, libc::c_int, off64_t) -> isize);
260+
super::weak::weak!(
261+
fn preadv64(
262+
fd: libc::c_int,
263+
iovec: *const libc::iovec,
264+
n_iovec: libc::c_int,
265+
offset: off64_t,
266+
) -> isize;
267+
);
261268

262269
match preadv64.get() {
263270
Some(preadv) => {
@@ -286,7 +293,14 @@ impl FileDesc {
286293
// use "weak" linking.
287294
#[cfg(target_vendor = "apple")]
288295
pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
289-
super::weak::weak!(fn preadv(libc::c_int, *const libc::iovec, libc::c_int, off64_t) -> isize);
296+
super::weak::weak!(
297+
fn preadv(
298+
fd: libc::c_int,
299+
iovec: *const libc::iovec,
300+
n_iovec: libc::c_int,
301+
offset: off64_t,
302+
) -> isize;
303+
);
290304

291305
match preadv.get() {
292306
Some(preadv) => {
@@ -428,14 +442,14 @@ impl FileDesc {
428442
// implementation if `pwritev` is not available.
429443
#[cfg(all(target_os = "android", target_pointer_width = "64"))]
430444
pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
431-
super::weak::syscall! {
445+
super::weak::syscall!(
432446
fn pwritev(
433447
fd: libc::c_int,
434448
iovec: *const libc::iovec,
435449
n_iovec: libc::c_int,
436-
offset: off64_t
437-
) -> isize
438-
}
450+
offset: off64_t,
451+
) -> isize;
452+
);
439453

440454
let ret = cvt(unsafe {
441455
pwritev(
@@ -450,7 +464,14 @@ impl FileDesc {
450464

451465
#[cfg(all(target_os = "android", target_pointer_width = "32"))]
452466
pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
453-
super::weak::weak!(fn pwritev64(libc::c_int, *const libc::iovec, libc::c_int, off64_t) -> isize);
467+
super::weak::weak!(
468+
fn pwritev64(
469+
fd: libc::c_int,
470+
iovec: *const libc::iovec,
471+
n_iovec: libc::c_int,
472+
offset: off64_t,
473+
) -> isize;
474+
);
454475

455476
match pwritev64.get() {
456477
Some(pwritev) => {
@@ -479,7 +500,14 @@ impl FileDesc {
479500
// use "weak" linking.
480501
#[cfg(target_vendor = "apple")]
481502
pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
482-
super::weak::weak!(fn pwritev(libc::c_int, *const libc::iovec, libc::c_int, off64_t) -> isize);
503+
super::weak::weak!(
504+
fn pwritev(
505+
fd: libc::c_int,
506+
iovec: *const libc::iovec,
507+
n_iovec: libc::c_int,
508+
offset: off64_t,
509+
) -> isize;
510+
);
483511

484512
match pwritev.get() {
485513
Some(pwritev) => {

‎std/src/sys/pal/unix/kernel_copy.rs‎

Lines changed: 8 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -604,16 +604,16 @@ pub(super) fn copy_regular_files(reader: RawFd, writer: RawFd, max_len: u64) ->
604604
_ => true,
605605
};
606606

607-
syscall! {
607+
syscall!(
608608
fn copy_file_range(
609609
fd_in: libc::c_int,
610610
off_in: *mut libc::loff_t,
611611
fd_out: libc::c_int,
612612
off_out: *mut libc::loff_t,
613613
len: libc::size_t,
614-
flags: libc::c_uint
615-
) -> libc::ssize_t
616-
}
614+
flags: libc::c_uint,
615+
) -> libc::ssize_t;
616+
);
617617

618618
fn probe_copy_file_range_support() -> u8 {
619619
// In some cases, we cannot determine availability from the first
@@ -727,16 +727,16 @@ fn sendfile_splice(mode: SpliceMode, reader: RawFd, writer: RawFd, len: u64) ->
727727
// Android builds use feature level 14, but the libc wrapper for splice is
728728
// gated on feature level 21+, so we have to invoke the syscall directly.
729729
#[cfg(target_os = "android")]
730-
syscall! {
730+
syscall!(
731731
fn splice(
732732
srcfd: libc::c_int,
733733
src_offset: *const i64,
734734
dstfd: libc::c_int,
735735
dst_offset: *const i64,
736736
len: libc::size_t,
737-
flags: libc::c_int
738-
) -> libc::ssize_t
739-
}
737+
flags: libc::c_int,
738+
) -> libc::ssize_t;
739+
);
740740

741741
#[cfg(target_os = "linux")]
742742
use libc::splice;

‎std/src/sys/pal/unix/stack_overflow.rs‎

Lines changed: 22 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -424,18 +424,32 @@ mod imp {
424424

425425
let pages = PAGES.get_or_init(|| {
426426
use crate::sys::weak::dlsym;
427-
dlsym!(fn sysctlbyname(*const libc::c_char, *mut libc::c_void, *mut libc::size_t, *const libc::c_void, libc::size_t) -> libc::c_int);
427+
dlsym!(
428+
fn sysctlbyname(
429+
name: *const libc::c_char,
430+
oldp: *mut libc::c_void,
431+
oldlenp: *mut libc::size_t,
432+
newp: *const libc::c_void,
433+
newlen: libc::size_t,
434+
) -> libc::c_int;
435+
);
428436
let mut guard: usize = 0;
429437
let mut size = size_of_val(&guard);
430438
let oid = c"security.bsd.stack_guard_page";
431439
match sysctlbyname.get() {
432-
Some(fcn) if unsafe {
433-
fcn(oid.as_ptr(),
434-
(&raw mut guard).cast(),
435-
&raw mut size,
436-
ptr::null_mut(),
437-
0) == 0
438-
} => guard,
440+
Some(fcn)
441+
if unsafe {
442+
fcn(
443+
oid.as_ptr(),
444+
(&raw mut guard).cast(),
445+
&raw mut size,
446+
ptr::null_mut(),
447+
0,
448+
) == 0
449+
} =>
450+
{
451+
guard
452+
}
439453
_ => 1,
440454
}
441455
});

‎std/src/sys/pal/unix/thread.rs‎

Lines changed: 8 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -193,11 +193,12 @@ impl Thread {
193193
// and its metadata from LLVM IR.
194194
#[no_sanitize(cfi)]
195195
pub fn set_name(name: &CStr) {
196-
weak! {
196+
weak!(
197197
fn pthread_setname_np(
198-
libc::pthread_t, *const libc::c_char
199-
) -> libc::c_int
200-
}
198+
thread: libc::pthread_t,
199+
name: *const libc::c_char,
200+
) -> libc::c_int;
201+
);
201202

202203
if let Some(f) = pthread_setname_np.get() {
203204
#[cfg(target_os = "nto")]
@@ -762,7 +763,9 @@ unsafe fn min_stack_size(attr: *const libc::pthread_attr_t) -> usize {
762763
// We use dlsym to avoid an ELF version dependency on GLIBC_PRIVATE. (#23628)
763764
// We shouldn't really be using such an internal symbol, but there's currently
764765
// no other way to account for the TLS size.
765-
dlsym!(fn __pthread_get_minstack(*const libc::pthread_attr_t) -> libc::size_t);
766+
dlsym!(
767+
fn __pthread_get_minstack(attr: *const libc::pthread_attr_t) -> libc::size_t;
768+
);
766769

767770
match __pthread_get_minstack.get() {
768771
None => libc::PTHREAD_STACK_MIN,

‎std/src/sys/pal/unix/time.rs‎

Lines changed: 6 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -123,7 +123,12 @@ impl Timespec {
123123

124124
// __clock_gettime64 was added to 32-bit arches in glibc 2.34,
125125
// and it handles both vDSO calls and ENOSYS fallbacks itself.
126-
weak!(fn __clock_gettime64(libc::clockid_t, *mut __timespec64) -> libc::c_int);
126+
weak!(
127+
fn __clock_gettime64(
128+
clockid: libc::clockid_t,
129+
tp: *mut __timespec64,
130+
) -> libc::c_int;
131+
);
127132

128133
if let Some(clock_gettime64) = __clock_gettime64.get() {
129134
let mut t = MaybeUninit::uninit();

‎std/src/sys/pal/unix/weak.rs‎

Lines changed: 24 additions & 16 deletions
Original file line numberDiff line numberDiff line change
@@ -29,7 +29,7 @@ use crate::{mem, ptr};
2929
// We can use true weak linkage on ELF targets.
3030
#[cfg(all(unix, not(target_vendor = "apple")))]
3131
pub(crate) macro weak {
32-
(fn $name:ident($($t:ty),*) -> $ret:ty) => (
32+
(fn $name:ident($($param:ident : $t:ty),* $(,)?) -> $ret:ty;) => (
3333
let ref $name: ExternWeak<unsafe extern "C" fn($($t),*) -> $ret> = {
3434
unsafe extern "C" {
3535
#[linkage = "extern_weak"]
@@ -62,10 +62,16 @@ impl<F: Copy> ExternWeak<F> {
6262
}
6363

6464
pub(crate) macro dlsym {
65-
(fn $name:ident($($t:ty),*) -> $ret:ty) => (
66-
dlsym!(fn $name($($t),*) -> $ret, stringify!($name));
65+
(fn $name:ident($($param:ident : $t:ty),* $(,)?) -> $ret:ty;) => (
66+
dlsym!(
67+
#[link_name = stringify!($name)]
68+
fn $name($($param : $t),*) -> $ret;
69+
);
6770
),
68-
(fn $name:ident($($t:ty),*) -> $ret:ty, $sym:expr) => (
71+
(
72+
#[link_name = $sym:expr]
73+
fn $name:ident($($param:ident : $t:ty),* $(,)?) -> $ret:ty;
74+
) => (
6975
static DLSYM: DlsymWeak<unsafe extern "C" fn($($t),*) -> $ret> =
7076
DlsymWeak::new(concat!($sym, '\0'));
7177
let $name = &DLSYM;
@@ -143,15 +149,15 @@ unsafe fn fetch(name: &str) -> *mut libc::c_void {
143149

144150
#[cfg(not(any(target_os = "linux", target_os = "android")))]
145151
pub(crate) macro syscall {
146-
(fn $name:ident($($arg_name:ident: $t:ty),*) -> $ret:ty) => (
152+
(fn $name:ident($($param:ident : $t:ty),* $(,)?) -> $ret:ty;) => (
147153
// FIXME(#115199): Rust currently omits weak function definitions
148154
// and its metadata from LLVM IR.
149155
#[no_sanitize(cfi)]
150-
unsafe fn $name($($arg_name: $t),*) -> $ret {
151-
weak! { fn $name($($t),*) -> $ret }
156+
unsafe fn $name($($param: $t),*) -> $ret {
157+
weak!(fn $name($($param: $t),*) -> $ret;);
152158

153159
if let Some(fun) = $name.get() {
154-
fun($($arg_name),*)
160+
fun($($param),*)
155161
} else {
156162
super::os::set_errno(libc::ENOSYS);
157163
-1
@@ -162,26 +168,28 @@ pub(crate) macro syscall {
162168

163169
#[cfg(any(target_os = "linux", target_os = "android"))]
164170
pub(crate) macro syscall {
165-
(fn $name:ident($($arg_name:ident: $t:ty),*) -> $ret:ty) => (
166-
unsafe fn $name($($arg_name:$t),*) -> $ret {
167-
weak! { fn $name($($t),*) -> $ret }
171+
(
172+
fn $name:ident($($param:ident : $t:ty),* $(,)?) -> $ret:ty;
173+
) => (
174+
unsafe fn $name($($param: $t),*) -> $ret {
175+
weak!(fn $name($($param: $t),*) -> $ret;);
168176

169177
// Use a weak symbol from libc when possible, allowing `LD_PRELOAD`
170178
// interposition, but if it's not found just use a raw syscall.
171179
if let Some(fun) = $name.get() {
172-
fun($($arg_name),*)
180+
fun($($param),*)
173181
} else {
174-
libc::syscall(libc::${concat(SYS_, $name)}, $($arg_name),*) as $ret
182+
libc::syscall(libc::${concat(SYS_, $name)}, $($param),*) as $ret
175183
}
176184
}
177185
)
178186
}
179187

180188
#[cfg(any(target_os = "linux", target_os = "android"))]
181189
pub(crate) macro raw_syscall {
182-
(fn $name:ident($($arg_name:ident: $t:ty),*) -> $ret:ty) => (
183-
unsafe fn $name($($arg_name:$t),*) -> $ret {
184-
libc::syscall(libc::${concat(SYS_, $name)}, $($arg_name),*) as $ret
190+
(fn $name:ident($($param:ident : $t:ty),* $(,)?) -> $ret:ty;) => (
191+
unsafe fn $name($($param: $t),*) -> $ret {
192+
libc::syscall(libc::${concat(SYS_, $name)}, $($param),*) as $ret
185193
}
186194
)
187195
}

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