zig/lib/std/os/linux/x86_64.zig
Alex Rønne Petersen 36dbe66cf4
std: stop exposing anything having to do with ucontext_t
This type is useful for two things:

* Doing non-local control flow with ucontext.h functions.
* Inspecting machine state in a signal handler.

The first use case is not one we support; we no longer expose bindings to those
functions in the standard library. They're also deprecated in POSIX and, as a
result, not available in musl.

The second use case is valid, but is very poorly served by the standard library.
As evidenced by my changes to std.debug.cpu_context.signal_context_t, users will
be better served rolling their own ucontext_t and especially mcontext_t types
which fit their specific situation. Further, these types tend to evolve
frequently as architectures evolve, and the standard library has not done a good
job keeping up, or even providing them for all supported targets.
2025-10-10 04:43:18 +02:00

249 lines
6.2 KiB
Zig

const builtin = @import("builtin");
const std = @import("../../std.zig");
const maxInt = std.math.maxInt;
const linux = std.os.linux;
const SYS = linux.SYS;
const iovec = std.posix.iovec;
const iovec_const = std.posix.iovec_const;
const pid_t = linux.pid_t;
const uid_t = linux.uid_t;
const gid_t = linux.gid_t;
const clock_t = linux.clock_t;
const stack_t = linux.stack_t;
const sigset_t = linux.sigset_t;
const sockaddr = linux.sockaddr;
const socklen_t = linux.socklen_t;
const timespec = linux.timespec;
pub fn syscall0(number: SYS) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn syscall1(number: SYS, arg1: usize) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
[arg1] "{rdi}" (arg1),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn syscall2(number: SYS, arg1: usize, arg2: usize) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
[arg1] "{rdi}" (arg1),
[arg2] "{rsi}" (arg2),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn syscall3(number: SYS, arg1: usize, arg2: usize, arg3: usize) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
[arg1] "{rdi}" (arg1),
[arg2] "{rsi}" (arg2),
[arg3] "{rdx}" (arg3),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn syscall4(number: SYS, arg1: usize, arg2: usize, arg3: usize, arg4: usize) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
[arg1] "{rdi}" (arg1),
[arg2] "{rsi}" (arg2),
[arg3] "{rdx}" (arg3),
[arg4] "{r10}" (arg4),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn syscall5(number: SYS, arg1: usize, arg2: usize, arg3: usize, arg4: usize, arg5: usize) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
[arg1] "{rdi}" (arg1),
[arg2] "{rsi}" (arg2),
[arg3] "{rdx}" (arg3),
[arg4] "{r10}" (arg4),
[arg5] "{r8}" (arg5),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn syscall6(
number: SYS,
arg1: usize,
arg2: usize,
arg3: usize,
arg4: usize,
arg5: usize,
arg6: usize,
) usize {
return asm volatile ("syscall"
: [ret] "={rax}" (-> usize),
: [number] "{rax}" (@intFromEnum(number)),
[arg1] "{rdi}" (arg1),
[arg2] "{rsi}" (arg2),
[arg3] "{rdx}" (arg3),
[arg4] "{r10}" (arg4),
[arg5] "{r8}" (arg5),
[arg6] "{r9}" (arg6),
: .{ .rcx = true, .r11 = true, .memory = true });
}
pub fn clone() callconv(.naked) usize {
asm volatile (
\\ movl $56,%%eax // SYS_clone
\\ movq %%rdi,%%r11
\\ movq %%rdx,%%rdi
\\ movq %%r8,%%rdx
\\ movq %%r9,%%r8
\\ movq 8(%%rsp),%%r10
\\ movq %%r11,%%r9
\\ andq $-16,%%rsi
\\ subq $8,%%rsi
\\ movq %%rcx,(%%rsi)
\\ syscall
\\ testq %%rax,%%rax
\\ jz 1f
\\ retq
\\
\\1:
);
if (builtin.unwind_tables != .none or !builtin.strip_debug_info) asm volatile (
\\ .cfi_undefined %%rip
);
asm volatile (
\\ xorl %%ebp,%%ebp
\\
\\ popq %%rdi
\\ callq *%%r9
\\ movl %%eax,%%edi
\\ movl $60,%%eax // SYS_exit
\\ syscall
\\
);
}
pub const restore = restore_rt;
pub fn restore_rt() callconv(.naked) noreturn {
switch (@import("builtin").zig_backend) {
.stage2_c => asm volatile (
\\ movl %[number], %%eax
\\ syscall
:
: [number] "i" (@intFromEnum(SYS.rt_sigreturn)),
),
else => asm volatile (
\\ syscall
:
: [number] "{rax}" (@intFromEnum(SYS.rt_sigreturn)),
),
}
}
pub const mode_t = usize;
pub const time_t = isize;
pub const nlink_t = usize;
pub const blksize_t = isize;
pub const blkcnt_t = isize;
pub const F = struct {
pub const DUPFD = 0;
pub const GETFD = 1;
pub const SETFD = 2;
pub const GETFL = 3;
pub const SETFL = 4;
pub const GETLK = 5;
pub const SETLK = 6;
pub const SETLKW = 7;
pub const SETOWN = 8;
pub const GETOWN = 9;
pub const SETSIG = 10;
pub const GETSIG = 11;
pub const SETOWN_EX = 15;
pub const GETOWN_EX = 16;
pub const GETOWNER_UIDS = 17;
pub const RDLCK = 0;
pub const WRLCK = 1;
pub const UNLCK = 2;
};
pub const VDSO = struct {
pub const CGT_SYM = "__vdso_clock_gettime";
pub const CGT_VER = "LINUX_2.6";
pub const GETCPU_SYM = "__vdso_getcpu";
pub const GETCPU_VER = "LINUX_2.6";
};
pub const ARCH = struct {
pub const SET_GS = 0x1001;
pub const SET_FS = 0x1002;
pub const GET_FS = 0x1003;
pub const GET_GS = 0x1004;
};
pub const Flock = extern struct {
type: i16,
whence: i16,
start: off_t,
len: off_t,
pid: pid_t,
};
pub const off_t = i64;
pub const ino_t = u64;
pub const dev_t = u64;
// The `stat` definition used by the Linux kernel.
pub const Stat = extern struct {
dev: dev_t,
ino: ino_t,
nlink: usize,
mode: u32,
uid: uid_t,
gid: gid_t,
__pad0: u32,
rdev: dev_t,
size: off_t,
blksize: isize,
blocks: i64,
atim: timespec,
mtim: timespec,
ctim: timespec,
__unused: [3]isize,
pub fn atime(self: @This()) timespec {
return self.atim;
}
pub fn mtime(self: @This()) timespec {
return self.mtim;
}
pub fn ctime(self: @This()) timespec {
return self.ctim;
}
};
pub const timeval = extern struct {
sec: isize,
usec: isize,
};
pub const timezone = extern struct {
minuteswest: i32,
dsttime: i32,
};
pub const Elf_Symndx = u32;