blob: 3a4801905356331defe5574ea7073c957ed6169a [file] [log] [blame]
use std::ffi::OsStr;
use log::trace;
use rustc_middle::ty::layout::LayoutOf;
use rustc_span::Symbol;
use rustc_target::abi::{Align, Size};
use rustc_target::spec::abi::Abi;
use crate::*;
use shims::foreign_items::EmulateByNameResult;
use shims::unix::fs::EvalContextExt as _;
use shims::unix::mem::EvalContextExt as _;
use shims::unix::sync::EvalContextExt as _;
use shims::unix::thread::EvalContextExt as _;
impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
fn emulate_foreign_item_by_name(
&mut self,
link_name: Symbol,
abi: Abi,
args: &[OpTy<'tcx, Provenance>],
dest: &PlaceTy<'tcx, Provenance>,
) -> InterpResult<'tcx, EmulateByNameResult<'mir, 'tcx>> {
let this = self.eval_context_mut();
// See `fn emulate_foreign_item_by_name` in `shims/foreign_items.rs` for the general pattern.
#[rustfmt::skip]
match link_name.as_str() {
// Environment related shims
"getenv" => {
let [name] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.getenv(name)?;
this.write_pointer(result, dest)?;
}
"unsetenv" => {
let [name] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.unsetenv(name)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"setenv" => {
let [name, value, overwrite] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.read_scalar(overwrite)?.to_i32()?;
let result = this.setenv(name, value)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"getcwd" => {
let [buf, size] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.getcwd(buf, size)?;
this.write_pointer(result, dest)?;
}
"chdir" => {
let [path] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.chdir(path)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
// File related shims
"open" | "open64" => {
// `open` is variadic, the third argument is only present when the second argument has O_CREAT (or on linux O_TMPFILE, but miri doesn't support that) set
this.check_abi_and_shim_symbol_clash(abi, Abi::C { unwind: false }, link_name)?;
let result = this.open(args)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"close" => {
let [fd] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.close(fd)?;
this.write_scalar(result, dest)?;
}
"fcntl" => {
// `fcntl` is variadic. The argument count is checked based on the first argument
// in `this.fcntl()`, so we do not use `check_shim` here.
this.check_abi_and_shim_symbol_clash(abi, Abi::C { unwind: false }, link_name)?;
let result = this.fcntl(args)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"read" => {
let [fd, buf, count] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let fd = this.read_scalar(fd)?.to_i32()?;
let buf = this.read_pointer(buf)?;
let count = this.read_target_usize(count)?;
let result = this.read(fd, buf, count)?;
this.write_scalar(Scalar::from_target_isize(result, this), dest)?;
}
"write" => {
let [fd, buf, n] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let fd = this.read_scalar(fd)?.to_i32()?;
let buf = this.read_pointer(buf)?;
let count = this.read_target_usize(n)?;
trace!("Called write({:?}, {:?}, {:?})", fd, buf, count);
let result = this.write(fd, buf, count)?;
// Now, `result` is the value we return back to the program.
this.write_scalar(Scalar::from_target_isize(result, this), dest)?;
}
"unlink" => {
let [path] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.unlink(path)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"symlink" => {
let [target, linkpath] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.symlink(target, linkpath)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"rename" => {
let [oldpath, newpath] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.rename(oldpath, newpath)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"mkdir" => {
let [path, mode] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.mkdir(path, mode)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"rmdir" => {
let [path] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.rmdir(path)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"opendir" => {
let [name] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.opendir(name)?;
this.write_scalar(result, dest)?;
}
"closedir" => {
let [dirp] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.closedir(dirp)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"lseek64" => {
let [fd, offset, whence] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.lseek64(fd, offset, whence)?;
this.write_scalar(result, dest)?;
}
"ftruncate64" => {
let [fd, length] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.ftruncate64(fd, length)?;
this.write_scalar(result, dest)?;
}
"fsync" => {
let [fd] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.fsync(fd)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"fdatasync" => {
let [fd] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.fdatasync(fd)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"readlink" => {
let [pathname, buf, bufsize] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.readlink(pathname, buf, bufsize)?;
this.write_scalar(Scalar::from_target_isize(result, this), dest)?;
}
"posix_fadvise" => {
let [fd, offset, len, advice] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.read_scalar(fd)?.to_i32()?;
this.read_target_isize(offset)?;
this.read_target_isize(len)?;
this.read_scalar(advice)?.to_i32()?;
// fadvise is only informational, we can ignore it.
this.write_null(dest)?;
}
"realpath" => {
let [path, resolved_path] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.realpath(path, resolved_path)?;
this.write_scalar(result, dest)?;
}
"mkstemp" => {
let [template] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.mkstemp(template)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
// Time related shims
"gettimeofday" => {
let [tv, tz] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.gettimeofday(tv, tz)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"clock_gettime" => {
let [clk_id, tp] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.clock_gettime(clk_id, tp)?;
this.write_scalar(result, dest)?;
}
// Allocation
"posix_memalign" => {
let [ret, align, size] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let ret = this.deref_pointer(ret)?;
let align = this.read_target_usize(align)?;
let size = this.read_target_usize(size)?;
// Align must be power of 2, and also at least ptr-sized (POSIX rules).
// But failure to adhere to this is not UB, it's an error condition.
if !align.is_power_of_two() || align < this.pointer_size().bytes() {
let einval = this.eval_libc_i32("EINVAL");
this.write_int(einval, dest)?;
} else {
if size == 0 {
this.write_null(&ret)?;
} else {
let ptr = this.allocate_ptr(
Size::from_bytes(size),
Align::from_bytes(align).unwrap(),
MiriMemoryKind::C.into(),
)?;
this.write_pointer(ptr, &ret)?;
}
this.write_null(dest)?;
}
}
"mmap" => {
let [addr, length, prot, flags, fd, offset] = this.check_shim(abi, Abi::C {unwind: false}, link_name, args)?;
let ptr = this.mmap(addr, length, prot, flags, fd, offset)?;
this.write_scalar(ptr, dest)?;
}
"munmap" => {
let [addr, length] = this.check_shim(abi, Abi::C {unwind: false}, link_name, args)?;
let result = this.munmap(addr, length)?;
this.write_scalar(result, dest)?;
}
// Dynamic symbol loading
"dlsym" => {
let [handle, symbol] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.read_target_usize(handle)?;
let symbol = this.read_pointer(symbol)?;
let symbol_name = this.read_c_str(symbol)?;
if let Some(dlsym) = Dlsym::from_str(symbol_name, &this.tcx.sess.target.os)? {
let ptr = this.create_fn_alloc_ptr(FnVal::Other(dlsym));
this.write_pointer(ptr, dest)?;
} else {
this.write_null(dest)?;
}
}
// Querying system information
"sysconf" => {
let [name] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let name = this.read_scalar(name)?.to_i32()?;
// FIXME: Which of these are POSIX, and which are GNU/Linux?
// At least the names seem to all also exist on macOS.
let sysconfs: &[(&str, fn(&MiriInterpCx<'_, '_>) -> Scalar<Provenance>)] = &[
("_SC_PAGESIZE", |this| Scalar::from_int(this.machine.page_size, this.pointer_size())),
("_SC_NPROCESSORS_CONF", |this| Scalar::from_int(this.machine.num_cpus, this.pointer_size())),
("_SC_NPROCESSORS_ONLN", |this| Scalar::from_int(this.machine.num_cpus, this.pointer_size())),
// 512 seems to be a reasonable default. The value is not critical, in
// the sense that getpwuid_r takes and checks the buffer length.
("_SC_GETPW_R_SIZE_MAX", |this| Scalar::from_int(512, this.pointer_size()))
];
let mut result = None;
for &(sysconf_name, value) in sysconfs {
let sysconf_name = this.eval_libc_i32(sysconf_name);
if sysconf_name == name {
result = Some(value(this));
break;
}
}
if let Some(result) = result {
this.write_scalar(result, dest)?;
} else {
throw_unsup_format!("unimplemented sysconf name: {}", name)
}
}
// Thread-local storage
"pthread_key_create" => {
let [key, dtor] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let key_place = this.deref_pointer_as(key, this.libc_ty_layout("pthread_key_t"))?;
let dtor = this.read_pointer(dtor)?;
// Extract the function type out of the signature (that seems easier than constructing it ourselves).
let dtor = if !this.ptr_is_null(dtor)? {
Some(this.get_ptr_fn(dtor)?.as_instance()?)
} else {
None
};
// Figure out how large a pthread TLS key actually is.
// To this end, deref the argument type. This is `libc::pthread_key_t`.
let key_type = key.layout.ty
.builtin_deref(true)
.ok_or_else(|| err_ub_format!(
"wrong signature used for `pthread_key_create`: first argument must be a raw pointer."
))?
.ty;
let key_layout = this.layout_of(key_type)?;
// Create key and write it into the memory where `key_ptr` wants it.
let key = this.machine.tls.create_tls_key(dtor, key_layout.size)?;
this.write_scalar(Scalar::from_uint(key, key_layout.size), &key_place)?;
// Return success (`0`).
this.write_null(dest)?;
}
"pthread_key_delete" => {
let [key] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let key = this.read_scalar(key)?.to_bits(key.layout.size)?;
this.machine.tls.delete_tls_key(key)?;
// Return success (0)
this.write_null(dest)?;
}
"pthread_getspecific" => {
let [key] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let key = this.read_scalar(key)?.to_bits(key.layout.size)?;
let active_thread = this.get_active_thread();
let ptr = this.machine.tls.load_tls(key, active_thread, this)?;
this.write_scalar(ptr, dest)?;
}
"pthread_setspecific" => {
let [key, new_ptr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let key = this.read_scalar(key)?.to_bits(key.layout.size)?;
let active_thread = this.get_active_thread();
let new_data = this.read_scalar(new_ptr)?;
this.machine.tls.store_tls(key, active_thread, new_data, &*this.tcx)?;
// Return success (`0`).
this.write_null(dest)?;
}
// Synchronization primitives
"pthread_mutexattr_init" => {
let [attr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutexattr_init(attr)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutexattr_settype" => {
let [attr, kind] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutexattr_settype(attr, kind)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutexattr_destroy" => {
let [attr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutexattr_destroy(attr)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutex_init" => {
let [mutex, attr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutex_init(mutex, attr)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutex_lock" => {
let [mutex] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutex_lock(mutex)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutex_trylock" => {
let [mutex] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutex_trylock(mutex)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutex_unlock" => {
let [mutex] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutex_unlock(mutex)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_mutex_destroy" => {
let [mutex] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_mutex_destroy(mutex)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_rwlock_rdlock" => {
let [rwlock] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_rwlock_rdlock(rwlock)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_rwlock_tryrdlock" => {
let [rwlock] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_rwlock_tryrdlock(rwlock)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_rwlock_wrlock" => {
let [rwlock] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_rwlock_wrlock(rwlock)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_rwlock_trywrlock" => {
let [rwlock] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_rwlock_trywrlock(rwlock)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_rwlock_unlock" => {
let [rwlock] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_rwlock_unlock(rwlock)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_rwlock_destroy" => {
let [rwlock] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_rwlock_destroy(rwlock)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_condattr_init" => {
let [attr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_condattr_init(attr)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_condattr_destroy" => {
let [attr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_condattr_destroy(attr)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_cond_init" => {
let [cond, attr] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_cond_init(cond, attr)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_cond_signal" => {
let [cond] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_cond_signal(cond)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_cond_broadcast" => {
let [cond] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_cond_broadcast(cond)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_cond_wait" => {
let [cond, mutex] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_cond_wait(cond, mutex)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_cond_timedwait" => {
let [cond, mutex, abstime] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.pthread_cond_timedwait(cond, mutex, abstime, dest)?;
}
"pthread_cond_destroy" => {
let [cond] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_cond_destroy(cond)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
// Threading
"pthread_create" => {
let [thread, attr, start, arg] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_create(thread, attr, start, arg)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_join" => {
let [thread, retval] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_join(thread, retval)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_detach" => {
let [thread] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.pthread_detach(thread)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"pthread_self" => {
let [] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let res = this.pthread_self()?;
this.write_scalar(res, dest)?;
}
"sched_yield" => {
let [] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.sched_yield()?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
"nanosleep" => {
let [req, rem] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.nanosleep(req, rem)?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
// Miscellaneous
"isatty" => {
let [fd] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let result = this.isatty(fd)?;
this.write_scalar(result, dest)?;
}
"pthread_atfork" => {
let [prepare, parent, child] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.read_pointer(prepare)?;
this.read_pointer(parent)?;
this.read_pointer(child)?;
// We do not support forking, so there is nothing to do here.
this.write_null(dest)?;
}
"strerror_r" | "__xpg_strerror_r" => {
let [errnum, buf, buflen] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let errnum = this.read_scalar(errnum)?;
let buf = this.read_pointer(buf)?;
let buflen = this.read_target_usize(buflen)?;
let error = this.try_errnum_to_io_error(errnum)?;
let formatted = match error {
Some(err) => format!("{err}"),
None => format!("<unknown errnum in strerror_r: {errnum}>"),
};
let (complete, _) = this.write_os_str_to_c_str(OsStr::new(&formatted), buf, buflen)?;
let ret = if complete { 0 } else { this.eval_libc_i32("ERANGE") };
this.write_int(ret, dest)?;
}
"getpid" => {
let [] = this.check_shim(abi, Abi::C { unwind: false}, link_name, args)?;
let result = this.getpid()?;
this.write_scalar(Scalar::from_i32(result), dest)?;
}
// Incomplete shims that we "stub out" just to get pre-main initialization code to work.
// These shims are enabled only when the caller is in the standard library.
"pthread_attr_getguardsize"
if this.frame_in_std() => {
let [_attr, guard_size] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let guard_size = this.deref_pointer(guard_size)?;
let guard_size_layout = this.libc_ty_layout("size_t");
this.write_scalar(Scalar::from_uint(this.machine.page_size, guard_size_layout.size), &guard_size)?;
// Return success (`0`).
this.write_null(dest)?;
}
| "pthread_attr_init"
| "pthread_attr_destroy"
if this.frame_in_std() => {
let [_] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.write_null(dest)?;
}
| "pthread_attr_setstacksize"
if this.frame_in_std() => {
let [_, _] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.write_null(dest)?;
}
"pthread_attr_getstack"
if this.frame_in_std() => {
// We don't support "pthread_attr_setstack", so we just pretend all stacks have the same values here.
// Hence we can mostly ignore the input `attr_place`.
let [attr_place, addr_place, size_place] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let _attr_place = this.deref_pointer_as(attr_place, this.libc_ty_layout("pthread_attr_t"))?;
let addr_place = this.deref_pointer(addr_place)?;
let size_place = this.deref_pointer(size_place)?;
this.write_scalar(
Scalar::from_uint(this.machine.stack_addr, this.pointer_size()),
&addr_place,
)?;
this.write_scalar(
Scalar::from_uint(this.machine.stack_size, this.pointer_size()),
&size_place,
)?;
// Return success (`0`).
this.write_null(dest)?;
}
| "signal"
| "sigaltstack"
if this.frame_in_std() => {
let [_, _] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.write_null(dest)?;
}
| "sigaction"
| "mprotect"
if this.frame_in_std() => {
let [_, _, _] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.write_null(dest)?;
}
"getuid"
if this.frame_in_std() => {
let [] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
// FOr now, just pretend we always have this fixed UID.
this.write_int(super::UID, dest)?;
}
"getpwuid_r" if this.frame_in_std() => {
let [uid, pwd, buf, buflen, result] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.check_no_isolation("`getpwuid_r`")?;
let uid = this.read_scalar(uid)?.to_u32()?;
let pwd = this.deref_pointer_as(pwd, this.libc_ty_layout("passwd"))?;
let buf = this.read_pointer(buf)?;
let buflen = this.read_target_usize(buflen)?;
let result = this.deref_pointer(result)?;
// Must be for "us".
if uid != crate::shims::unix::UID {
throw_unsup_format!("`getpwuid_r` on other users is not supported");
}
// Reset all fields to `uninit` to make sure nobody reads them.
// (This is a std-only shim so we are okay with such hacks.)
this.write_uninit(&pwd)?;
// We only set the home_dir field.
#[allow(deprecated)]
let home_dir = std::env::home_dir().unwrap();
let (written, _) = this.write_path_to_c_str(&home_dir, buf, buflen)?;
let pw_dir = this.project_field_named(&pwd, "pw_dir")?;
this.write_pointer(buf, &pw_dir)?;
if written {
this.write_pointer(pwd.ptr, &result)?;
this.write_null(dest)?;
} else {
this.write_null(&result)?;
this.write_scalar(this.eval_libc("ERANGE"), dest)?;
}
}
// Platform-specific shims
_ => {
let target_os = &*this.tcx.sess.target.os;
return match target_os {
"android" => shims::unix::android::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, abi, args, dest),
"freebsd" => shims::unix::freebsd::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, abi, args, dest),
"linux" => shims::unix::linux::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, abi, args, dest),
"macos" => shims::unix::macos::foreign_items::EvalContextExt::emulate_foreign_item_by_name(this, link_name, abi, args, dest),
_ => Ok(EmulateByNameResult::NotSupported),
};
}
};
Ok(EmulateByNameResult::NeedsJumping)
}
}