move remaining shims

Author: pvdrz

src/shims/foreign_items.rs

@@ -193,6 +193,8 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
+        // Here we dispatch all the shims for foreign functions. If you have a platform specific
+        // shim, add it to the corresponding submodule.
         match link_name {
             "malloc" => {
                 let size = this.read_scalar(args[0])?.to_machine_usize(this)?;
@@ -439,67 +441,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
                 this.write_scalar(Scalar::from_f64(res), dest)?;
             }
 
-            // Some things needed for `sys::thread` initialization to go through.
-            | "signal"
-            | "sigaction"
-            | "sigaltstack"
-            => {
-                this.write_scalar(Scalar::from_int(0, dest.layout.size), dest)?;
-            }
-
-            "sysconf" => {
-                let name = this.read_scalar(args[0])?.to_i32()?;
-
-                trace!("sysconf() called with name {}", name);
-                // TODO: Cache the sysconf integers via Miri's global cache.
-                let paths = &[
-                    (&["libc", "_SC_PAGESIZE"], Scalar::from_int(PAGE_SIZE, dest.layout.size)),
-                    (&["libc", "_SC_GETPW_R_SIZE_MAX"], Scalar::from_int(-1, dest.layout.size)),
-                    (
-                        &["libc", "_SC_NPROCESSORS_ONLN"],
-                        Scalar::from_int(NUM_CPUS, dest.layout.size),
-                    ),
-                ];
-                let mut result = None;
-                for &(path, path_value) in paths {
-                    if let Some(val) = this.eval_path_scalar(path)? {
-                        let val = val.to_i32()?;
-                        if val == name {
-                            result = Some(path_value);
-                            break;
-                        }
-                    }
-                }
-                if let Some(result) = result {
-                    this.write_scalar(result, dest)?;
-                } else {
-                    throw_unsup_format!("Unimplemented sysconf name: {}", name)
-                }
-            }
-
-            "sched_getaffinity" => {
-                // Return an error; `num_cpus` then falls back to `sysconf`.
-                this.write_scalar(Scalar::from_int(-1, dest.layout.size), dest)?;
-            }
-
-            "isatty" => {
-                this.write_null(dest)?;
-            }
-
-            "posix_fadvise" => {
-                // fadvise is only informational, we can ignore it.
-                this.write_null(dest)?;
-            }
-
-            "mmap" => {
-                // This is a horrible hack, but since the guard page mechanism calls mmap and expects a particular return value, we just give it that value.
-                let addr = this.read_scalar(args[0])?.not_undef()?;
-                this.write_scalar(addr, dest)?;
-            }
-            "mprotect" => {
-                this.write_null(dest)?;
-            }
-
             _ => match this.tcx.sess.target.target.target_os.to_lowercase().as_str() {
                 "linux" | "macos" => posix::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest)?,
                 "windows" => windows::EvalContextExt::emulate_foreign_item_by_name(this, link_name, args, dest)?,

src/shims/foreign_items/posix.rs

@@ -266,6 +266,62 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
                 this.write_null(dest)?;
             }
 
+            // Some things needed for `sys::thread` initialization to go through.
+            | "signal"
+            | "sigaction"
+            | "sigaltstack"
+            => {
+                this.write_scalar(Scalar::from_int(0, dest.layout.size), dest)?;
+            }
+
+            "sysconf" => {
+                let name = this.read_scalar(args[0])?.to_i32()?;
+
+                trace!("sysconf() called with name {}", name);
+                // TODO: Cache the sysconf integers via Miri's global cache.
+                let paths = &[
+                    (&["libc", "_SC_PAGESIZE"], Scalar::from_int(PAGE_SIZE, dest.layout.size)),
+                    (&["libc", "_SC_GETPW_R_SIZE_MAX"], Scalar::from_int(-1, dest.layout.size)),
+                    (
+                        &["libc", "_SC_NPROCESSORS_ONLN"],
+                        Scalar::from_int(NUM_CPUS, dest.layout.size),
+                    ),
+                ];
+                let mut result = None;
+                for &(path, path_value) in paths {
+                    if let Some(val) = this.eval_path_scalar(path)? {
+                        let val = val.to_i32()?;
+                        if val == name {
+                            result = Some(path_value);
+                            break;
+                        }
+                    }
+                }
+                if let Some(result) = result {
+                    this.write_scalar(result, dest)?;
+                } else {
+                    throw_unsup_format!("Unimplemented sysconf name: {}", name)
+                }
+            }
+
+            "isatty" => {
+                this.write_null(dest)?;
+            }
+
+            "posix_fadvise" => {
+                // fadvise is only informational, we can ignore it.
+                this.write_null(dest)?;
+            }
+
+            "mmap" => {
+                // This is a horrible hack, but since the guard page mechanism calls mmap and expects a particular return value, we just give it that value.
+                let addr = this.read_scalar(args[0])?.not_undef()?;
+                this.write_scalar(addr, dest)?;
+            }
+
+            "mprotect" => {
+                this.write_null(dest)?;
+            }
 
             _ => {
                 match this.tcx.sess.target.target.target_os.to_lowercase().as_str() {

src/shims/foreign_items/posix/linux.rs

@@ -75,6 +75,11 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
                 super::getrandom(this, args, dest)?;
             }
 
+            "sched_getaffinity" => {
+                // Return an error; `num_cpus` then falls back to `sysconf`.
+                this.write_scalar(Scalar::from_int(-1, dest.layout.size), dest)?;
+            }
+
             _ => throw_unsup_format!("can't call foreign function: {}", link_name),
         };