-use rustc_middle::ty::{TyKind, TypeAndMut};
+use rustc_middle::ty::{layout::TyAndLayout, TyKind, TypeAndMut};
use rustc_target::abi::{LayoutOf, Size};
use crate::stacked_borrows::Tag;
+use crate::thread::BlockSetId;
use crate::*;
+fn assert_ptr_target_min_size<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ operand: OpTy<'tcx, Tag>,
+ min_size: u64,
+) -> InterpResult<'tcx, ()> {
+ let target_ty = match operand.layout.ty.kind {
+ TyKind::RawPtr(TypeAndMut { ty, mutbl: _ }) => ty,
+ _ => panic!("Argument to pthread function was not a raw pointer"),
+ };
+ let target_layout = ecx.layout_of(target_ty)?;
+ assert!(target_layout.size.bytes() >= min_size);
+ Ok(())
+}
+
+fn get_at_offset<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ op: OpTy<'tcx, Tag>,
+ offset: u64,
+ layout: TyAndLayout<'tcx>,
+ min_size: u64,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ // Ensure that the following read at an offset to the attr pointer is within bounds
+ assert_ptr_target_min_size(ecx, op, min_size)?;
+ let op_place = ecx.deref_operand(op)?;
+ let value_place = op_place.offset(Size::from_bytes(offset), MemPlaceMeta::None, layout, ecx)?;
+ ecx.read_scalar(value_place.into())
+}
+
+fn set_at_offset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ op: OpTy<'tcx, Tag>,
+ offset: u64,
+ value: impl Into<ScalarMaybeUndef<Tag>>,
+ layout: TyAndLayout<'tcx>,
+ min_size: u64,
+) -> InterpResult<'tcx, ()> {
+ // Ensure that the following write at an offset to the attr pointer is within bounds
+ assert_ptr_target_min_size(ecx, op, min_size)?;
+ let op_place = ecx.deref_operand(op)?;
+ let value_place = op_place.offset(Size::from_bytes(offset), MemPlaceMeta::None, layout, ecx)?;
+ ecx.write_scalar(value.into(), value_place.into())
+}
+
+// pthread_mutexattr_t is either 4 or 8 bytes, depending on the platform.
+
+// Our chosen memory layout for emulation (does not have to match the platform layout!):
+// store an i32 in the first four bytes equal to the corresponding libc mutex kind constant
+// (e.g. PTHREAD_MUTEX_NORMAL).
+
+const PTHREAD_MUTEXATTR_T_MIN_SIZE: u64 = 4;
+
+fn mutexattr_get_kind<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ attr_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, attr_op, 0, ecx.machine.layouts.i32, PTHREAD_MUTEXATTR_T_MIN_SIZE)
+}
+
+fn mutexattr_set_kind<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ attr_op: OpTy<'tcx, Tag>,
+ kind: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, attr_op, 0, kind, ecx.machine.layouts.i32, PTHREAD_MUTEXATTR_T_MIN_SIZE)
+}
+
+// pthread_mutex_t is between 24 and 48 bytes, depending on the platform.
+
+// Our chosen memory layout for the emulated mutex (does not have to match the platform layout!):
+// bytes 0-3: reserved for signature on macOS
+// (need to avoid this because it is set by static initializer macros)
+// bytes 4-7: count of how many times this mutex has been locked, as a u32
+// bytes 8-11: when count > 0, id of the owner thread as a u32
+// bytes 12-15 or 16-19 (depending on platform): mutex kind, as an i32
+// (the kind has to be at its offset for compatibility with static initializer macros)
+// bytes 20-23: when count > 0, id of the blockset in which the blocked threads are waiting.
+
+const PTHREAD_MUTEX_T_MIN_SIZE: u64 = 24;
+
+fn mutex_get_locked_count<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, mutex_op, 4, ecx.machine.layouts.u32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_set_locked_count<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+ locked_count: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, mutex_op, 4, locked_count, ecx.machine.layouts.u32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_get_owner<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, mutex_op, 8, ecx.machine.layouts.u32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_set_owner<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+ owner: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, mutex_op, 8, owner, ecx.machine.layouts.u32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_get_kind<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ let offset = if ecx.pointer_size().bytes() == 8 { 16 } else { 12 };
+ get_at_offset(ecx, mutex_op, offset, ecx.machine.layouts.i32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_set_kind<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+ kind: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ let offset = if ecx.pointer_size().bytes() == 8 { 16 } else { 12 };
+ set_at_offset(ecx, mutex_op, offset, kind, ecx.machine.layouts.i32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_get_blockset<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, mutex_op, 20, ecx.machine.layouts.u32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_set_blockset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+ blockset: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, mutex_op, 20, blockset, ecx.machine.layouts.u32, PTHREAD_MUTEX_T_MIN_SIZE)
+}
+
+fn mutex_get_or_create_blockset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ mutex_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, BlockSetId> {
+ let blockset = mutex_get_blockset(ecx, mutex_op)?.to_u32()?;
+ if blockset == 0 {
+ // 0 is a default value and also not a valid blockset id. Need to
+ // allocate a new blockset.
+ let blockset = ecx.create_blockset()?;
+ mutex_set_blockset(ecx, mutex_op, blockset.to_u32_scalar())?;
+ Ok(blockset)
+ } else {
+ Ok(BlockSetId::new(blockset))
+ }
+}
+
+// pthread_rwlock_t is between 32 and 56 bytes, depending on the platform.
+
+// Our chosen memory layout for the emulated rwlock (does not have to match the platform layout!):
+// bytes 0-3: reserved for signature on macOS
+// (need to avoid this because it is set by static initializer macros)
+// bytes 4-7: reader count, as a u32
+// bytes 8-11: writer count, as a u32
+// bytes 12-15: when writer or reader count > 0, id of the blockset in which the
+// blocked writers are waiting.
+// bytes 16-20: when writer count > 0, id of the blockset in which the blocked
+// readers are waiting.
+
+const PTHREAD_RWLOCK_T_MIN_SIZE: u64 = 20;
+
+fn rwlock_get_readers<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, rwlock_op, 4, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_set_readers<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+ readers: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, rwlock_op, 4, readers, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_get_writers<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, rwlock_op, 8, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_set_writers<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+ writers: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, rwlock_op, 8, writers, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_get_writer_blockset<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, rwlock_op, 12, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_set_writer_blockset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+ blockset: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, rwlock_op, 12, blockset, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_get_or_create_writer_blockset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, BlockSetId> {
+ let blockset = rwlock_get_writer_blockset(ecx, rwlock_op)?.to_u32()?;
+ if blockset == 0 {
+ // 0 is a default value and also not a valid blockset id. Need to
+ // allocate a new blockset.
+ let blockset = ecx.create_blockset()?;
+ rwlock_set_writer_blockset(ecx, rwlock_op, blockset.to_u32_scalar())?;
+ Ok(blockset)
+ } else {
+ Ok(BlockSetId::new(blockset))
+ }
+}
+
+fn rwlock_get_reader_blockset<'mir, 'tcx: 'mir>(
+ ecx: &MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
+ get_at_offset(ecx, rwlock_op, 16, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_set_reader_blockset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+ blockset: impl Into<ScalarMaybeUndef<Tag>>,
+) -> InterpResult<'tcx, ()> {
+ set_at_offset(ecx, rwlock_op, 16, blockset, ecx.machine.layouts.u32, PTHREAD_RWLOCK_T_MIN_SIZE)
+}
+
+fn rwlock_get_or_create_reader_blockset<'mir, 'tcx: 'mir>(
+ ecx: &mut MiriEvalContext<'mir, 'tcx>,
+ rwlock_op: OpTy<'tcx, Tag>,
+) -> InterpResult<'tcx, BlockSetId> {
+ let blockset = rwlock_get_reader_blockset(ecx, rwlock_op)?.to_u32()?;
+ if blockset == 0 {
+ // 0 is a default value and also not a valid blockset id. Need to
+ // allocate a new blockset.
+ let blockset = ecx.create_blockset()?;
+ rwlock_set_reader_blockset(ecx, rwlock_op, blockset.to_u32_scalar())?;
+ Ok(blockset)
+ } else {
+ Ok(BlockSetId::new(blockset))
+ }
+}
+
impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
fn pthread_mutexattr_init(&mut self, attr_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let attr = this.read_scalar(attr_op)?.not_undef()?;
- if this.is_null(attr)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let default_kind = this.eval_libc("PTHREAD_MUTEX_DEFAULT")?;
mutexattr_set_kind(this, attr_op, default_kind)?;
) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let attr = this.read_scalar(attr_op)?.not_undef()?;
- if this.is_null(attr)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let kind = this.read_scalar(kind_op)?.not_undef()?;
if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")?
|| kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")?
fn pthread_mutexattr_destroy(&mut self, attr_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let attr = this.read_scalar(attr_op)?.not_undef()?;
- if this.is_null(attr)? {
- return this.eval_libc_i32("EINVAL");
- }
-
mutexattr_set_kind(this, attr_op, ScalarMaybeUndef::Undef)?;
Ok(0)
) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let mutex = this.read_scalar(mutex_op)?.not_undef()?;
- if this.is_null(mutex)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let attr = this.read_scalar(attr_op)?.not_undef()?;
let kind = if this.is_null(attr)? {
this.eval_libc("PTHREAD_MUTEX_DEFAULT")?
fn pthread_mutex_lock(&mut self, mutex_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let mutex = this.read_scalar(mutex_op)?.not_undef()?;
- if this.is_null(mutex)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let kind = mutex_get_kind(this, mutex_op)?.not_undef()?;
let locked_count = mutex_get_locked_count(this, mutex_op)?.to_u32()?;
+ let active_thread = this.get_active_thread()?;
- if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")? {
- if locked_count == 0 {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(1))?;
- Ok(0)
- } else {
- throw_unsup_format!("Deadlock due to locking a PTHREAD_MUTEX_NORMAL mutex twice");
- }
- } else if kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")? {
- if locked_count == 0 {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(1))?;
+ if locked_count == 0 {
+ // The mutex is unlocked. Let's lock it.
+ mutex_set_locked_count(this, mutex_op, Scalar::from_u32(1))?;
+ mutex_set_owner(this, mutex_op, active_thread.to_u32_scalar())?;
+ Ok(0)
+ } else {
+ // The mutex is locked. Let's check by whom.
+ let owner_thread: ThreadId =
+ mutex_get_owner(this, mutex_op)?.not_undef()?.to_u32()?.into();
+ if owner_thread != active_thread {
+ // Block the active thread.
+ let blockset = mutex_get_or_create_blockset(this, mutex_op)?;
+ this.block_active_thread(blockset)?;
Ok(0)
} else {
- this.eval_libc_i32("EDEADLK")
- }
- } else if kind == this.eval_libc("PTHREAD_MUTEX_RECURSIVE")? {
- match locked_count.checked_add(1) {
- Some(new_count) => {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(new_count))?;
- Ok(0)
+ // Trying to acquire the same mutex again.
+ if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")? {
+ throw_machine_stop!(TerminationInfo::Deadlock);
+ } else if kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")? {
+ this.eval_libc_i32("EDEADLK")
+ } else if kind == this.eval_libc("PTHREAD_MUTEX_RECURSIVE")? {
+ match locked_count.checked_add(1) {
+ Some(new_count) => {
+ mutex_set_locked_count(this, mutex_op, Scalar::from_u32(new_count))?;
+ Ok(0)
+ }
+ None => this.eval_libc_i32("EAGAIN"),
+ }
+ } else {
+ throw_ub_format!("called pthread_mutex_lock on an unsupported type of mutex");
}
- None => this.eval_libc_i32("EAGAIN"),
}
- } else {
- this.eval_libc_i32("EINVAL")
}
}
fn pthread_mutex_trylock(&mut self, mutex_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let mutex = this.read_scalar(mutex_op)?.not_undef()?;
- if this.is_null(mutex)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let kind = mutex_get_kind(this, mutex_op)?.not_undef()?;
let locked_count = mutex_get_locked_count(this, mutex_op)?.to_u32()?;
+ let active_thread = this.get_active_thread()?;
- if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")?
- || kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")?
- {
- if locked_count == 0 {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(1))?;
- Ok(0)
- } else {
+ if locked_count == 0 {
+ // The mutex is unlocked. Let's lock it.
+ mutex_set_locked_count(this, mutex_op, Scalar::from_u32(1))?;
+ mutex_set_owner(this, mutex_op, active_thread.to_u32_scalar())?;
+ Ok(0)
+ } else {
+ let owner_thread: ThreadId = mutex_get_owner(this, mutex_op)?.to_u32()?.into();
+ if owner_thread != active_thread {
this.eval_libc_i32("EBUSY")
- }
- } else if kind == this.eval_libc("PTHREAD_MUTEX_RECURSIVE")? {
- match locked_count.checked_add(1) {
- Some(new_count) => {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(new_count))?;
- Ok(0)
+ } else {
+ if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")?
+ || kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")?
+ {
+ this.eval_libc_i32("EBUSY")
+ } else if kind == this.eval_libc("PTHREAD_MUTEX_RECURSIVE")? {
+ match locked_count.checked_add(1) {
+ Some(new_count) => {
+ mutex_set_locked_count(this, mutex_op, Scalar::from_u32(new_count))?;
+ Ok(0)
+ }
+ None => this.eval_libc_i32("EAGAIN"),
+ }
+ } else {
+ throw_ub_format!(
+ "called pthread_mutex_trylock on an unsupported type of mutex"
+ );
}
- None => this.eval_libc_i32("EAGAIN"),
}
- } else {
- this.eval_libc_i32("EINVAL")
}
}
fn pthread_mutex_unlock(&mut self, mutex_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let mutex = this.read_scalar(mutex_op)?.not_undef()?;
- if this.is_null(mutex)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let kind = mutex_get_kind(this, mutex_op)?.not_undef()?;
let locked_count = mutex_get_locked_count(this, mutex_op)?.to_u32()?;
-
- if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")? {
- if locked_count != 0 {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(0))?;
- Ok(0)
+ let owner_thread: ThreadId = mutex_get_owner(this, mutex_op)?.to_u32()?.into();
+
+ if owner_thread != this.get_active_thread()? {
+ throw_ub_format!("called pthread_mutex_unlock on a mutex owned by another thread");
+ } else if locked_count == 1 {
+ let blockset = mutex_get_or_create_blockset(this, mutex_op)?;
+ if let Some(new_owner) = this.unblock_some_thread(blockset)? {
+ // We have at least one thread waiting on this mutex. Transfer
+ // ownership to it.
+ mutex_set_owner(this, mutex_op, new_owner.to_u32_scalar())?;
} else {
- throw_ub_format!(
- "Attempted to unlock a PTHREAD_MUTEX_NORMAL mutex that was not locked"
- );
- }
- } else if kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")? {
- if locked_count != 0 {
+ // No thread is waiting on this mutex.
mutex_set_locked_count(this, mutex_op, Scalar::from_u32(0))?;
- Ok(0)
- } else {
- this.eval_libc_i32("EPERM")
}
- } else if kind == this.eval_libc("PTHREAD_MUTEX_RECURSIVE")? {
- match locked_count.checked_sub(1) {
- Some(new_count) => {
- mutex_set_locked_count(this, mutex_op, Scalar::from_u32(new_count))?;
- Ok(0)
- }
- None => {
- // locked_count was already zero
- this.eval_libc_i32("EPERM")
+ Ok(0)
+ } else {
+ if kind == this.eval_libc("PTHREAD_MUTEX_NORMAL")? {
+ throw_ub_format!("unlocked a PTHREAD_MUTEX_NORMAL mutex that was not locked");
+ } else if kind == this.eval_libc("PTHREAD_MUTEX_ERRORCHECK")? {
+ this.eval_libc_i32("EPERM")
+ } else if kind == this.eval_libc("PTHREAD_MUTEX_RECURSIVE")? {
+ match locked_count.checked_sub(1) {
+ Some(new_count) => {
+ mutex_set_locked_count(this, mutex_op, Scalar::from_u32(new_count))?;
+ Ok(0)
+ }
+ None => {
+ // locked_count was already zero
+ this.eval_libc_i32("EPERM")
+ }
}
+ } else {
+ throw_ub_format!("called pthread_mutex_unlock on an unsupported type of mutex");
}
- } else {
- this.eval_libc_i32("EINVAL")
}
}
fn pthread_mutex_destroy(&mut self, mutex_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let mutex = this.read_scalar(mutex_op)?.not_undef()?;
- if this.is_null(mutex)? {
- return this.eval_libc_i32("EINVAL");
- }
-
if mutex_get_locked_count(this, mutex_op)?.to_u32()? != 0 {
- return this.eval_libc_i32("EBUSY");
+ throw_ub_format!("destroyed a locked mutex");
}
mutex_set_kind(this, mutex_op, ScalarMaybeUndef::Undef)?;
mutex_set_locked_count(this, mutex_op, ScalarMaybeUndef::Undef)?;
+ mutex_set_blockset(this, mutex_op, ScalarMaybeUndef::Undef)?;
Ok(0)
}
fn pthread_rwlock_rdlock(&mut self, rwlock_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let rwlock = this.read_scalar(rwlock_op)?.not_undef()?;
- if this.is_null(rwlock)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let readers = rwlock_get_readers(this, rwlock_op)?.to_u32()?;
let writers = rwlock_get_writers(this, rwlock_op)?.to_u32()?;
+
if writers != 0 {
- throw_unsup_format!(
- "Deadlock due to read-locking a pthreads read-write lock while it is already write-locked"
- );
+ // The lock is locked by a writer.
+ assert_eq!(writers, 1);
+ let reader_blockset = rwlock_get_or_create_reader_blockset(this, rwlock_op)?;
+ this.block_active_thread(reader_blockset)?;
+ Ok(0)
} else {
match readers.checked_add(1) {
Some(new_readers) => {
fn pthread_rwlock_tryrdlock(&mut self, rwlock_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let rwlock = this.read_scalar(rwlock_op)?.not_undef()?;
- if this.is_null(rwlock)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let readers = rwlock_get_readers(this, rwlock_op)?.to_u32()?;
let writers = rwlock_get_writers(this, rwlock_op)?.to_u32()?;
if writers != 0 {
fn pthread_rwlock_wrlock(&mut self, rwlock_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let rwlock = this.read_scalar(rwlock_op)?.not_undef()?;
- if this.is_null(rwlock)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let readers = rwlock_get_readers(this, rwlock_op)?.to_u32()?;
let writers = rwlock_get_writers(this, rwlock_op)?.to_u32()?;
- if readers != 0 {
- throw_unsup_format!(
- "Deadlock due to write-locking a pthreads read-write lock while it is already read-locked"
- );
- } else if writers != 0 {
- throw_unsup_format!(
- "Deadlock due to write-locking a pthreads read-write lock while it is already write-locked"
- );
+ let writer_blockset = rwlock_get_or_create_writer_blockset(this, rwlock_op)?;
+ if readers != 0 || writers != 0 {
+ this.block_active_thread(writer_blockset)?;
} else {
rwlock_set_writers(this, rwlock_op, Scalar::from_u32(1))?;
- Ok(0)
}
+ Ok(0)
}
fn pthread_rwlock_trywrlock(&mut self, rwlock_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let rwlock = this.read_scalar(rwlock_op)?.not_undef()?;
- if this.is_null(rwlock)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let readers = rwlock_get_readers(this, rwlock_op)?.to_u32()?;
let writers = rwlock_get_writers(this, rwlock_op)?.to_u32()?;
if readers != 0 || writers != 0 {
}
}
+ // FIXME: We should check that this lock was locked by the active thread.
fn pthread_rwlock_unlock(&mut self, rwlock_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let rwlock = this.read_scalar(rwlock_op)?.not_undef()?;
- if this.is_null(rwlock)? {
- return this.eval_libc_i32("EINVAL");
- }
-
let readers = rwlock_get_readers(this, rwlock_op)?.to_u32()?;
let writers = rwlock_get_writers(this, rwlock_op)?.to_u32()?;
+ let writer_blockset = rwlock_get_or_create_writer_blockset(this, rwlock_op)?;
if let Some(new_readers) = readers.checked_sub(1) {
+ assert_eq!(writers, 0);
rwlock_set_readers(this, rwlock_op, Scalar::from_u32(new_readers))?;
+ if new_readers == 0 {
+ if let Some(_writer) = this.unblock_some_thread(writer_blockset)? {
+ rwlock_set_writers(this, rwlock_op, Scalar::from_u32(1))?;
+ }
+ }
Ok(0)
} else if writers != 0 {
+ let reader_blockset = rwlock_get_or_create_reader_blockset(this, rwlock_op)?;
rwlock_set_writers(this, rwlock_op, Scalar::from_u32(0))?;
+ if let Some(_writer) = this.unblock_some_thread(writer_blockset)? {
+ rwlock_set_writers(this, rwlock_op, Scalar::from_u32(1))?;
+ } else {
+ let mut readers = 0;
+ while let Some(_reader) = this.unblock_some_thread(reader_blockset)? {
+ readers += 1;
+ }
+ rwlock_set_readers(this, rwlock_op, Scalar::from_u32(readers))?
+ }
Ok(0)
} else {
- this.eval_libc_i32("EPERM")
+ throw_ub_format!("unlocked an rwlock that was not locked");
}
}
fn pthread_rwlock_destroy(&mut self, rwlock_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
let this = self.eval_context_mut();
- let rwlock = this.read_scalar(rwlock_op)?.not_undef()?;
- if this.is_null(rwlock)? {
- return this.eval_libc_i32("EINVAL");
- }
-
- if rwlock_get_readers(this, rwlock_op)?.to_u32()? != 0 {
- return this.eval_libc_i32("EBUSY");
- }
- if rwlock_get_writers(this, rwlock_op)?.to_u32()? != 0 {
- return this.eval_libc_i32("EBUSY");
+ if rwlock_get_readers(this, rwlock_op)?.to_u32()? != 0
+ || rwlock_get_writers(this, rwlock_op)?.to_u32()? != 0
+ {
+ throw_ub_format!("destroyed a locked rwlock");
}
rwlock_set_readers(this, rwlock_op, ScalarMaybeUndef::Undef)?;
rwlock_set_writers(this, rwlock_op, ScalarMaybeUndef::Undef)?;
+ rwlock_set_reader_blockset(this, rwlock_op, ScalarMaybeUndef::Undef)?;
+ rwlock_set_writer_blockset(this, rwlock_op, ScalarMaybeUndef::Undef)?;
Ok(0)
}
}
-
-fn assert_ptr_target_min_size<'mir, 'tcx: 'mir>(
- ecx: &MiriEvalContext<'mir, 'tcx>,
- operand: OpTy<'tcx, Tag>,
- min_size: u64,
-) -> InterpResult<'tcx, ()> {
- let target_ty = match operand.layout.ty.kind {
- TyKind::RawPtr(TypeAndMut { ty, mutbl: _ }) => ty,
- _ => panic!("Argument to pthread function was not a raw pointer"),
- };
- let target_layout = ecx.layout_of(target_ty)?;
- assert!(target_layout.size.bytes() >= min_size);
- Ok(())
-}
-
-// pthread_mutexattr_t is either 4 or 8 bytes, depending on the platform.
-
-// Our chosen memory layout: store an i32 in the first four bytes equal to the
-// corresponding libc mutex kind constant (i.e. PTHREAD_MUTEX_NORMAL)
-
-fn mutexattr_get_kind<'mir, 'tcx: 'mir>(
- ecx: &MiriEvalContext<'mir, 'tcx>,
- attr_op: OpTy<'tcx, Tag>,
-) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
- // Ensure that the following read at an offset to the attr pointer is within bounds
- assert_ptr_target_min_size(ecx, attr_op, 4)?;
- let attr_place = ecx.deref_operand(attr_op)?;
- let i32_layout = ecx.layout_of(ecx.tcx.types.i32)?;
- let kind_place = attr_place.offset(Size::ZERO, MemPlaceMeta::None, i32_layout, ecx)?;
- ecx.read_scalar(kind_place.into())
-}
-
-fn mutexattr_set_kind<'mir, 'tcx: 'mir>(
- ecx: &mut MiriEvalContext<'mir, 'tcx>,
- attr_op: OpTy<'tcx, Tag>,
- kind: impl Into<ScalarMaybeUndef<Tag>>,
-) -> InterpResult<'tcx, ()> {
- // Ensure that the following write at an offset to the attr pointer is within bounds
- assert_ptr_target_min_size(ecx, attr_op, 4)?;
- let attr_place = ecx.deref_operand(attr_op)?;
- let i32_layout = ecx.layout_of(ecx.tcx.types.i32)?;
- let kind_place = attr_place.offset(Size::ZERO, MemPlaceMeta::None, i32_layout, ecx)?;
- ecx.write_scalar(kind.into(), kind_place.into())
-}
-
-// pthread_mutex_t is between 24 and 48 bytes, depending on the platform.
-
-// Our chosen memory layout:
-// bytes 0-3: reserved for signature on macOS
-// (need to avoid this because it is set by static initializer macros)
-// bytes 4-7: count of how many times this mutex has been locked, as a u32
-// bytes 12-15: mutex kind, as an i32
-// (the kind has to be at this offset for compatibility with static initializer macros)
-
-fn mutex_get_locked_count<'mir, 'tcx: 'mir>(
- ecx: &MiriEvalContext<'mir, 'tcx>,
- mutex_op: OpTy<'tcx, Tag>,
-) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
- // Ensure that the following read at an offset to the mutex pointer is within bounds
- assert_ptr_target_min_size(ecx, mutex_op, 16)?;
- let mutex_place = ecx.deref_operand(mutex_op)?;
- let u32_layout = ecx.layout_of(ecx.tcx.types.u32)?;
- let locked_count_place =
- mutex_place.offset(Size::from_bytes(4), MemPlaceMeta::None, u32_layout, ecx)?;
- ecx.read_scalar(locked_count_place.into())
-}
-
-fn mutex_set_locked_count<'mir, 'tcx: 'mir>(
- ecx: &mut MiriEvalContext<'mir, 'tcx>,
- mutex_op: OpTy<'tcx, Tag>,
- locked_count: impl Into<ScalarMaybeUndef<Tag>>,
-) -> InterpResult<'tcx, ()> {
- // Ensure that the following write at an offset to the mutex pointer is within bounds
- assert_ptr_target_min_size(ecx, mutex_op, 16)?;
- let mutex_place = ecx.deref_operand(mutex_op)?;
- let u32_layout = ecx.layout_of(ecx.tcx.types.u32)?;
- let locked_count_place =
- mutex_place.offset(Size::from_bytes(4), MemPlaceMeta::None, u32_layout, ecx)?;
- ecx.write_scalar(locked_count.into(), locked_count_place.into())
-}
-
-fn mutex_get_kind<'mir, 'tcx: 'mir>(
- ecx: &MiriEvalContext<'mir, 'tcx>,
- mutex_op: OpTy<'tcx, Tag>,
-) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
- // Ensure that the following read at an offset to the mutex pointer is within bounds
- assert_ptr_target_min_size(ecx, mutex_op, 16)?;
- let mutex_place = ecx.deref_operand(mutex_op)?;
- let i32_layout = ecx.layout_of(ecx.tcx.types.i32)?;
- let kind_place =
- mutex_place.offset(Size::from_bytes(12), MemPlaceMeta::None, i32_layout, ecx)?;
- ecx.read_scalar(kind_place.into())
-}
-
-fn mutex_set_kind<'mir, 'tcx: 'mir>(
- ecx: &mut MiriEvalContext<'mir, 'tcx>,
- mutex_op: OpTy<'tcx, Tag>,
- kind: impl Into<ScalarMaybeUndef<Tag>>,
-) -> InterpResult<'tcx, ()> {
- // Ensure that the following write at an offset to the mutex pointer is within bounds
- assert_ptr_target_min_size(ecx, mutex_op, 16)?;
- let mutex_place = ecx.deref_operand(mutex_op)?;
- let i32_layout = ecx.layout_of(ecx.tcx.types.i32)?;
- let kind_place =
- mutex_place.offset(Size::from_bytes(12), MemPlaceMeta::None, i32_layout, ecx)?;
- ecx.write_scalar(kind.into(), kind_place.into())
-}
-
-// pthread_rwlock_t is between 32 and 56 bytes, depending on the platform.
-
-// Our chosen memory layout:
-// bytes 0-3: reserved for signature on macOS
-// (need to avoid this because it is set by static initializer macros)
-// bytes 4-7: reader count, as a u32
-// bytes 8-11: writer count, as a u32
-
-fn rwlock_get_readers<'mir, 'tcx: 'mir>(
- ecx: &MiriEvalContext<'mir, 'tcx>,
- rwlock_op: OpTy<'tcx, Tag>,
-) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
- // Ensure that the following read at an offset to the rwlock pointer is within bounds
- assert_ptr_target_min_size(ecx, rwlock_op, 12)?;
- let rwlock_place = ecx.deref_operand(rwlock_op)?;
- let u32_layout = ecx.layout_of(ecx.tcx.types.u32)?;
- let readers_place =
- rwlock_place.offset(Size::from_bytes(4), MemPlaceMeta::None, u32_layout, ecx)?;
- ecx.read_scalar(readers_place.into())
-}
-
-fn rwlock_set_readers<'mir, 'tcx: 'mir>(
- ecx: &mut MiriEvalContext<'mir, 'tcx>,
- rwlock_op: OpTy<'tcx, Tag>,
- readers: impl Into<ScalarMaybeUndef<Tag>>,
-) -> InterpResult<'tcx, ()> {
- // Ensure that the following write at an offset to the rwlock pointer is within bounds
- assert_ptr_target_min_size(ecx, rwlock_op, 12)?;
- let rwlock_place = ecx.deref_operand(rwlock_op)?;
- let u32_layout = ecx.layout_of(ecx.tcx.types.u32)?;
- let readers_place =
- rwlock_place.offset(Size::from_bytes(4), MemPlaceMeta::None, u32_layout, ecx)?;
- ecx.write_scalar(readers.into(), readers_place.into())
-}
-
-fn rwlock_get_writers<'mir, 'tcx: 'mir>(
- ecx: &MiriEvalContext<'mir, 'tcx>,
- rwlock_op: OpTy<'tcx, Tag>,
-) -> InterpResult<'tcx, ScalarMaybeUndef<Tag>> {
- // Ensure that the following read at an offset to the rwlock pointer is within bounds
- assert_ptr_target_min_size(ecx, rwlock_op, 12)?;
- let rwlock_place = ecx.deref_operand(rwlock_op)?;
- let u32_layout = ecx.layout_of(ecx.tcx.types.u32)?;
- let writers_place =
- rwlock_place.offset(Size::from_bytes(8), MemPlaceMeta::None, u32_layout, ecx)?;
- ecx.read_scalar(writers_place.into())
-}
-
-fn rwlock_set_writers<'mir, 'tcx: 'mir>(
- ecx: &mut MiriEvalContext<'mir, 'tcx>,
- rwlock_op: OpTy<'tcx, Tag>,
- writers: impl Into<ScalarMaybeUndef<Tag>>,
-) -> InterpResult<'tcx, ()> {
- // Ensure that the following write at an offset to the rwlock pointer is within bounds
- assert_ptr_target_min_size(ecx, rwlock_op, 12)?;
- let rwlock_place = ecx.deref_operand(rwlock_op)?;
- let u32_layout = ecx.layout_of(ecx.tcx.types.u32)?;
- let writers_place =
- rwlock_place.offset(Size::from_bytes(8), MemPlaceMeta::None, u32_layout, ecx)?;
- ecx.write_scalar(writers.into(), writers_place.into())
-}
projects / rust.git / blobdiff