X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Fhelpers.rs;h=f7be3de8e481227ba2d0077d757ec4d146bf9822;hb=cf9340113efcf5c7bea4a143f42c8ea47da4550e;hp=e3f818414da3d9a79fdf64b8193b5b08a57b8508;hpb=78311a713218b9923cd5ab73b62a9fe2485c7d22;p=rust.git

diff --git a/src/helpers.rs b/src/helpers.rs
index e3f818414da..f7be3de8e48 100644
--- a/src/helpers.rs
+++ b/src/helpers.rs
@@ -1,10 +1,11 @@
-use std::mem;
+use std::{mem, iter};
+use std::ffi::{OsStr, OsString};
 
 use rustc::hir::def_id::{DefId, CRATE_DEF_INDEX};
 use rustc::mir;
 use rustc::ty::{
     self,
-    layout::{self, Align, LayoutOf, Size, TyLayout},
+    layout::{self, LayoutOf, Size, TyLayout},
 };
 
 use rand::RngCore;
@@ -57,7 +58,7 @@ fn write_null(&mut self, dest: PlaceTy<'tcx, Tag>) -> InterpResult<'tcx> {
     /// Test if this immediate equals 0.
     fn is_null(&self, val: Scalar<Tag>) -> InterpResult<'tcx, bool> {
         let this = self.eval_context_ref();
-        let null = Scalar::from_int(0, this.memory().pointer_size());
+        let null = Scalar::from_int(0, this.memory.pointer_size());
         this.ptr_eq(val, null)
     }
 
@@ -94,12 +95,6 @@ fn gen_random(
         }
         let this = self.eval_context_mut();
 
-        let ptr = this.memory().check_ptr_access(
-            ptr,
-            Size::from_bytes(len as u64),
-            Align::from_bytes(1).unwrap()
-        )?.expect("we already checked for size 0");
-
         let mut data = vec![0; len];
 
         if this.machine.communicate {
@@ -108,12 +103,11 @@ fn gen_random(
                 .map_err(|err| err_unsup_format!("getrandom failed: {}", err))?;
         }
         else {
-            let rng = this.memory_mut().extra.rng.get_mut();
+            let rng = this.memory.extra.rng.get_mut();
             rng.fill_bytes(&mut data);
         }
 
-        let tcx = &{this.tcx.tcx};
-        this.memory_mut().get_mut(ptr.alloc_id)?.write_bytes(tcx, ptr, &data)
+        this.memory.write_bytes(ptr, data.iter().copied())
     }
 
     /// Visits the memory covered by `place`, sensitive to freezing: the 3rd parameter
@@ -311,8 +305,7 @@ fn eval_libc_i32(&mut self, name: &str) -> InterpResult<'tcx, i32> {
     /// Helper function to get the `TyLayout` of a `libc` type
     fn libc_ty_layout(&mut self, name: &str) -> InterpResult<'tcx, TyLayout<'tcx>> {
         let this = self.eval_context_mut();
-        let tcx = &{ this.tcx.tcx };
-        let ty = this.resolve_path(&["libc", name])?.ty(*tcx);
+        let ty = this.resolve_path(&["libc", name])?.ty(*this.tcx);
         this.layout_of(ty)
     }
 
@@ -325,14 +318,12 @@ fn write_packed_immediates(
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
-        let tcx = &{ this.tcx.tcx };
-
         let mut offset = Size::from_bytes(0);
 
         for &imm in imms {
             this.write_immediate_to_mplace(
                 *imm,
-                place.offset(offset, None, imm.layout, tcx)?,
+                place.offset(offset, None, imm.layout, &*this.tcx)?,
             )?;
             offset += imm.layout.size;
         }
@@ -348,4 +339,124 @@ fn check_no_isolation(&mut self, name: &str) -> InterpResult<'tcx> {
         }
         Ok(())
     }
+
+    /// Sets the last error variable.
+    fn set_last_error(&mut self, scalar: Scalar<Tag>) -> InterpResult<'tcx> {
+        let this = self.eval_context_mut();
+        let errno_place = this.machine.last_error.unwrap();
+        this.write_scalar(scalar, errno_place.into())
+    }
+
+    /// Gets the last error variable.
+    fn get_last_error(&mut self) -> InterpResult<'tcx, Scalar<Tag>> {
+        let this = self.eval_context_mut();
+        let errno_place = this.machine.last_error.unwrap();
+        this.read_scalar(errno_place.into())?.not_undef()
+    }
+
+    /// Sets the last OS error using a `std::io::Error`. This function tries to produce the most
+    /// similar OS error from the `std::io::ErrorKind` and sets it as the last OS error.
+    fn set_last_error_from_io_error(&mut self, e: std::io::Error) -> InterpResult<'tcx> {
+        use std::io::ErrorKind::*;
+        let this = self.eval_context_mut();
+        let target = &this.tcx.tcx.sess.target.target;
+        let last_error = if target.options.target_family == Some("unix".to_owned()) {
+            this.eval_libc(match e.kind() {
+                ConnectionRefused => "ECONNREFUSED",
+                ConnectionReset => "ECONNRESET",
+                PermissionDenied => "EPERM",
+                BrokenPipe => "EPIPE",
+                NotConnected => "ENOTCONN",
+                ConnectionAborted => "ECONNABORTED",
+                AddrNotAvailable => "EADDRNOTAVAIL",
+                AddrInUse => "EADDRINUSE",
+                NotFound => "ENOENT",
+                Interrupted => "EINTR",
+                InvalidInput => "EINVAL",
+                TimedOut => "ETIMEDOUT",
+                AlreadyExists => "EEXIST",
+                WouldBlock => "EWOULDBLOCK",
+                _ => throw_unsup_format!("The {} error cannot be transformed into a raw os error", e)
+            })?
+        } else {
+            // FIXME: we have to implement the windows' equivalent of this.
+            throw_unsup_format!("Setting the last OS error from an io::Error is unsupported for {}.", target.target_os)
+        };
+        this.set_last_error(last_error)
+    }
+
+    /// Helper function that consumes an `std::io::Result<T>` and returns an
+    /// `InterpResult<'tcx,T>::Ok` instead. In case the result is an error, this function returns
+    /// `Ok(-1)` and sets the last OS error accordingly.
+    ///
+    /// This function uses `T: From<i32>` instead of `i32` directly because some IO related
+    /// functions return different integer types (like `read`, that returns an `i64`)
+    fn try_unwrap_io_result<T: From<i32>>(
+        &mut self,
+        result: std::io::Result<T>,
+    ) -> InterpResult<'tcx, T> {
+        match result {
+            Ok(ok) => Ok(ok),
+            Err(e) => {
+                self.eval_context_mut().set_last_error_from_io_error(e)?;
+                Ok((-1).into())
+            }
+        }
+    }
+
+    /// Helper function to read an OsString from a null-terminated sequence of bytes, which is what
+    /// the Unix APIs usually handle.
+    fn read_os_string_from_c_string(&mut self, scalar: Scalar<Tag>) -> InterpResult<'tcx, OsString> {
+        let bytes = self.eval_context_mut().memory.read_c_str(scalar)?;
+        Ok(bytes_to_os_str(bytes)?.into())
+    }
+
+    /// Helper function to write an OsStr as a null-terminated sequence of bytes, which is what
+    /// the Unix APIs usually handle. This function returns `Ok(false)` without trying to write if
+    /// `size` is not large enough to fit the contents of `os_string` plus a null terminator. It
+    /// returns `Ok(true)` if the writing process was successful.
+    fn write_os_str_to_c_string(
+        &mut self,
+        os_str: &OsStr,
+        scalar: Scalar<Tag>,
+        size: u64
+    ) -> InterpResult<'tcx, bool> {
+        let bytes = os_str_to_bytes(os_str)?;
+        // If `size` is smaller or equal than `bytes.len()`, writing `bytes` plus the required null
+        // terminator to memory using the `ptr` pointer would cause an overflow.
+        if size <= bytes.len() as u64 {
+            return Ok(false);
+        }
+        // FIXME: We should use `Iterator::chain` instead when rust-lang/rust#65704 lands.
+        self.eval_context_mut().memory.write_bytes(scalar, bytes.iter().copied().chain(iter::once(0u8)))?;
+        Ok(true)
+    }
+}
+
+#[cfg(target_os = "unix")]
+fn os_str_to_bytes<'tcx, 'a>(os_str: &'a OsStr) -> InterpResult<'tcx, &'a [u8]> {
+    std::os::unix::ffi::OsStringExt::into_bytes(os_str)
+}
+
+#[cfg(target_os = "unix")]
+fn bytes_to_os_str<'tcx, 'a>(bytes: &'a[u8]) -> InterpResult<'tcx, &'a OsStr> {
+    Ok(std::os::unix::ffi::OsStringExt::from_bytes(bytes))
+}
+
+// On non-unix platforms the best we can do to transform bytes from/to OS strings is to do the
+// intermediate transformation into strings. Which invalidates non-utf8 paths that are actually
+// valid.
+#[cfg(not(target_os = "unix"))]
+fn os_str_to_bytes<'tcx, 'a>(os_str: &'a OsStr) -> InterpResult<'tcx, &'a [u8]> {
+    os_str
+        .to_str()
+        .map(|s| s.as_bytes())
+        .ok_or_else(|| err_unsup_format!("{:?} is not a valid utf-8 string", os_str).into())
+}
+
+#[cfg(not(target_os = "unix"))]
+fn bytes_to_os_str<'tcx, 'a>(bytes: &'a[u8]) -> InterpResult<'tcx, &'a OsStr> {
+    let s = std::str::from_utf8(bytes)
+        .map_err(|_| err_unsup_format!("{:?} is not a valid utf-8 string", bytes))?;
+    Ok(&OsStr::new(s))
 }