1 use std::ffi::{OsString, OsStr};
3 use std::convert::TryFrom;
5 use crate::stacked_borrows::Tag;
6 use crate::rustc_target::abi::LayoutOf;
9 use rustc_data_structures::fx::FxHashMap;
10 use rustc::ty::layout::Size;
11 use rustc_mir::interpret::Pointer;
14 pub struct EnvVars<'tcx> {
15 /// Stores pointers to the environment variables. These variables must be stored as
16 /// null-terminated target strings (c_str or wide_str) with the `"{name}={value}"` format.
17 map: FxHashMap<OsString, Pointer<Tag>>,
19 /// Place where the `environ` static is stored. Lazily initialized, but then never changes.
20 pub(crate) environ: Option<MPlaceTy<'tcx, Tag>>,
23 impl<'tcx> EnvVars<'tcx> {
24 pub(crate) fn init<'mir>(
25 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
26 mut excluded_env_vars: Vec<String>,
27 ) -> InterpResult<'tcx> {
28 let target_os = ecx.tcx.sess.target.target.target_os.as_str();
29 if target_os == "windows" {
30 // Temporary hack: Exclude `TERM` var to avoid terminfo trying to open the termcap file.
31 // Can be removed once https://github.com/rust-lang/miri/issues/1013 is resolved.
32 excluded_env_vars.push("TERM".to_owned());
35 if ecx.machine.communicate {
36 for (name, value) in env::vars() {
37 if !excluded_env_vars.contains(&name) {
38 let var_ptr = match target_os {
39 "linux" | "macos" => alloc_env_var_as_c_str(name.as_ref(), value.as_ref(), ecx)?,
40 "windows" => alloc_env_var_as_wide_str(name.as_ref(), value.as_ref(), ecx)?,
41 unsupported => throw_unsup_format!("environment support for target OS `{}` not yet available", unsupported),
43 ecx.machine.env_vars.map.insert(OsString::from(name), var_ptr);
50 pub(crate) fn cleanup<'mir>(
51 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
52 ) -> InterpResult<'tcx> {
53 // Deallocate individual env vars.
54 for (_name, ptr) in ecx.machine.env_vars.map.drain() {
55 ecx.memory.deallocate(ptr, None, MiriMemoryKind::Env.into())?;
57 // Deallocate environ var list.
58 let environ = ecx.machine.env_vars.environ.take().unwrap();
59 let old_vars_ptr = ecx.read_scalar(environ.into())?.not_undef()?;
60 ecx.memory.deallocate(ecx.force_ptr(old_vars_ptr)?, None, MiriMemoryKind::Env.into())?;
65 fn alloc_env_var_as_c_str<'mir, 'tcx>(
68 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
69 ) -> InterpResult<'tcx, Pointer<Tag>> {
70 let mut name_osstring = name.to_os_string();
71 name_osstring.push("=");
72 name_osstring.push(value);
73 Ok(ecx.alloc_os_str_as_c_str(name_osstring.as_os_str(), MiriMemoryKind::Env.into()))
76 fn alloc_env_var_as_wide_str<'mir, 'tcx>(
79 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
80 ) -> InterpResult<'tcx, Pointer<Tag>> {
81 let mut name_osstring = name.to_os_string();
82 name_osstring.push("=");
83 name_osstring.push(value);
84 Ok(ecx.alloc_os_str_as_wide_str(name_osstring.as_os_str(), MiriMemoryKind::Env.into()))
87 impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
88 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
89 fn getenv(&mut self, name_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, Scalar<Tag>> {
90 let this = self.eval_context_mut();
91 let target_os = &this.tcx.sess.target.target.target_os;
92 assert!(target_os == "linux" || target_os == "macos", "`getenv` is only available for the UNIX target family");
94 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
95 let name = this.read_os_str_from_c_str(name_ptr)?;
96 Ok(match this.machine.env_vars.map.get(name) {
98 // The offset is used to strip the "{name}=" part of the string.
99 Scalar::from(var_ptr.offset(Size::from_bytes(u64::try_from(name.len()).unwrap().checked_add(1).unwrap()), this)?)
101 None => Scalar::ptr_null(&*this.tcx),
105 #[allow(non_snake_case)]
106 fn GetEnvironmentVariableW(
108 name_op: OpTy<'tcx, Tag>, // LPCWSTR
109 buf_op: OpTy<'tcx, Tag>, // LPWSTR
110 size_op: OpTy<'tcx, Tag>, // DWORD
111 ) -> InterpResult<'tcx, u64> {
112 let this = self.eval_context_mut();
113 this.assert_target_os("windows", "GetEnvironmentVariableW");
115 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
116 let name = this.read_os_str_from_wide_str(name_ptr)?;
117 Ok(match this.machine.env_vars.map.get(&name) {
119 // The offset is used to strip the "{name}=" part of the string.
120 let name_offset_bytes =
121 u64::try_from(name.len()).unwrap().checked_add(1).unwrap().checked_mul(2).unwrap();
122 let var_ptr = Scalar::from(var_ptr.offset(Size::from_bytes(name_offset_bytes), this)?);
123 let var = this.read_os_str_from_wide_str(var_ptr)?;
125 let buf_ptr = this.read_scalar(buf_op)?.not_undef()?;
126 // `buf_size` represents the size in characters.
127 let buf_size = u64::try_from(this.read_scalar(size_op)?.to_u32()?).unwrap();
128 let (success, len) = this.write_os_str_to_wide_str(&var, buf_ptr, buf_size)?;
131 // If the function succeeds, the return value is the number of characters stored in the buffer pointed to by lpBuffer,
132 // not including the terminating null character.
135 // If lpBuffer is not large enough to hold the data, the return value is the buffer size, in characters,
136 // required to hold the string and its terminating null character and the contents of lpBuffer are undefined.
141 let envvar_not_found = this.eval_path_scalar(&["std", "sys", "windows", "c", "ERROR_ENVVAR_NOT_FOUND"])?;
142 this.set_last_error(envvar_not_found.not_undef()?)?;
143 0 // return zero upon failure
148 #[allow(non_snake_case)]
149 fn GetEnvironmentStringsW(&mut self) -> InterpResult<'tcx, Scalar<Tag>> {
150 let this = self.eval_context_mut();
151 this.assert_target_os("windows", "GetEnvironmentStringsW");
153 // Info on layout of environment blocks in Windows:
154 // https://docs.microsoft.com/en-us/windows/win32/procthread/environment-variables
155 let mut env_vars = std::ffi::OsString::new();
156 for &item in this.machine.env_vars.map.values() {
157 let env_var = this.read_os_str_from_wide_str(Scalar::from(item))?;
158 env_vars.push(env_var);
161 // Allocate environment block & Store environment variables to environment block.
162 // Final null terminator(block terminator) is added by `alloc_os_str_to_wide_str`.
163 // FIXME: MemoryKind should be `Env`, blocked on https://github.com/rust-lang/rust/pull/70479.
164 let envblock_ptr = this.alloc_os_str_as_wide_str(&env_vars, MiriMemoryKind::WinHeap.into());
165 // If the function succeeds, the return value is a pointer to the environment block of the current process.
166 Ok(envblock_ptr.into())
169 #[allow(non_snake_case)]
170 fn FreeEnvironmentStringsW(&mut self, env_block_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
171 let this = self.eval_context_mut();
172 this.assert_target_os("windows", "FreeEnvironmentStringsW");
174 let env_block_ptr = this.read_scalar(env_block_op)?.not_undef()?;
175 // FIXME: MemoryKind should be `Env`, blocked on https://github.com/rust-lang/rust/pull/70479.
176 let result = this.memory.deallocate(this.force_ptr(env_block_ptr)?, None, MiriMemoryKind::WinHeap.into());
177 // If the function succeeds, the return value is nonzero.
178 Ok(result.is_ok() as i32)
183 name_op: OpTy<'tcx, Tag>,
184 value_op: OpTy<'tcx, Tag>,
185 ) -> InterpResult<'tcx, i32> {
186 let mut this = self.eval_context_mut();
187 let target_os = &this.tcx.sess.target.target.target_os;
188 assert!(target_os == "linux" || target_os == "macos", "`setenv` is only available for the UNIX target family");
190 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
191 let value_ptr = this.read_scalar(value_op)?.not_undef()?;
194 if !this.is_null(name_ptr)? {
195 let name = this.read_os_str_from_c_str(name_ptr)?;
196 if !name.is_empty() && !name.to_string_lossy().contains('=') {
197 let value = this.read_os_str_from_c_str(value_ptr)?;
198 new = Some((name.to_owned(), value.to_owned()));
201 if let Some((name, value)) = new {
202 let var_ptr = alloc_env_var_as_c_str(&name, &value, &mut this)?;
203 if let Some(var) = this.machine.env_vars.map.insert(name, var_ptr) {
205 .deallocate(var, None, MiriMemoryKind::Env.into())?;
207 this.update_environ()?;
208 Ok(0) // return zero on success
210 // name argument is a null pointer, points to an empty string, or points to a string containing an '=' character.
211 let einval = this.eval_libc("EINVAL")?;
212 this.set_last_error(einval)?;
217 #[allow(non_snake_case)]
218 fn SetEnvironmentVariableW(
220 name_op: OpTy<'tcx, Tag>, // LPCWSTR
221 value_op: OpTy<'tcx, Tag>, // LPCWSTR
222 ) -> InterpResult<'tcx, i32> {
223 let mut this = self.eval_context_mut();
224 this.assert_target_os("windows", "SetEnvironmentVariableW");
226 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
227 let value_ptr = this.read_scalar(value_op)?.not_undef()?;
229 if this.is_null(name_ptr)? {
230 // ERROR CODE is not clearly explained in docs.. For now, throw UB instead.
231 throw_ub_format!("pointer to environment variable name is NULL");
234 let name = this.read_os_str_from_wide_str(name_ptr)?;
236 throw_unsup_format!("environment variable name is an empty string");
237 } else if name.to_string_lossy().contains('=') {
238 throw_unsup_format!("environment variable name contains '='");
239 } else if this.is_null(value_ptr)? {
240 // Delete environment variable `{name}`
241 if let Some(var) = this.machine.env_vars.map.remove(&name) {
242 this.memory.deallocate(var, None, MiriMemoryKind::Env.into())?;
243 this.update_environ()?;
245 Ok(1) // return non-zero on success
247 let value = this.read_os_str_from_wide_str(value_ptr)?;
248 let var_ptr = alloc_env_var_as_wide_str(&name, &value, &mut this)?;
249 if let Some(var) = this.machine.env_vars.map.insert(name, var_ptr) {
251 .deallocate(var, None, MiriMemoryKind::Env.into())?;
253 this.update_environ()?;
254 Ok(1) // return non-zero on success
258 fn unsetenv(&mut self, name_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
259 let this = self.eval_context_mut();
260 let target_os = &this.tcx.sess.target.target.target_os;
261 assert!(target_os == "linux" || target_os == "macos", "`unsetenv` is only available for the UNIX target family");
263 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
264 let mut success = None;
265 if !this.is_null(name_ptr)? {
266 let name = this.read_os_str_from_c_str(name_ptr)?.to_owned();
267 if !name.is_empty() && !name.to_string_lossy().contains('=') {
268 success = Some(this.machine.env_vars.map.remove(&name));
271 if let Some(old) = success {
272 if let Some(var) = old {
274 .deallocate(var, None, MiriMemoryKind::Env.into())?;
276 this.update_environ()?;
279 // name argument is a null pointer, points to an empty string, or points to a string containing an '=' character.
280 let einval = this.eval_libc("EINVAL")?;
281 this.set_last_error(einval)?;
288 buf_op: OpTy<'tcx, Tag>,
289 size_op: OpTy<'tcx, Tag>,
290 ) -> InterpResult<'tcx, Scalar<Tag>> {
291 let this = self.eval_context_mut();
293 this.check_no_isolation("getcwd")?;
295 let buf = this.read_scalar(buf_op)?.not_undef()?;
296 let size = this.read_scalar(size_op)?.to_machine_usize(&*this.tcx)?;
297 // If we cannot get the current directory, we return null
298 match env::current_dir() {
300 if this.write_path_to_c_str(&cwd, buf, size)?.0 {
303 let erange = this.eval_libc("ERANGE")?;
304 this.set_last_error(erange)?;
306 Err(e) => this.set_last_error_from_io_error(e)?,
308 Ok(Scalar::ptr_null(&*this.tcx))
311 fn chdir(&mut self, path_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
312 let this = self.eval_context_mut();
314 this.check_no_isolation("chdir")?;
316 let path = this.read_path_from_c_str(this.read_scalar(path_op)?.not_undef()?)?;
318 match env::set_current_dir(path) {
321 this.set_last_error_from_io_error(e)?;
327 /// Updates the `environ` static.
328 /// The first time it gets called, also initializes `extra.environ`.
329 fn update_environ(&mut self) -> InterpResult<'tcx> {
330 let this = self.eval_context_mut();
331 // Deallocate the old environ list, if any.
332 if let Some(environ) = this.machine.env_vars.environ {
333 let old_vars_ptr = this.read_scalar(environ.into())?.not_undef()?;
334 this.memory.deallocate(this.force_ptr(old_vars_ptr)?, None, MiriMemoryKind::Env.into())?;
336 // No `environ` allocated yet, let's do that.
337 // This is memory backing an extern static, hence `Machine`, not `Env`.
338 let layout = this.layout_of(this.tcx.types.usize)?;
339 let place = this.allocate(layout, MiriMemoryKind::Machine.into());
340 this.write_scalar(Scalar::from_machine_usize(0, &*this.tcx), place.into())?;
341 this.machine.env_vars.environ = Some(place);
344 // Collect all the pointers to each variable in a vector.
345 let mut vars: Vec<Scalar<Tag>> = this.machine.env_vars.map.values().map(|&ptr| ptr.into()).collect();
346 // Add the trailing null pointer.
347 vars.push(Scalar::from_int(0, this.pointer_size()));
348 // Make an array with all these pointers inside Miri.
351 this.layout_of(tcx.mk_array(tcx.types.usize, u64::try_from(vars.len()).unwrap()))?;
352 let vars_place = this.allocate(vars_layout, MiriMemoryKind::Env.into());
353 for (idx, var) in vars.into_iter().enumerate() {
354 let place = this.mplace_field(vars_place, idx)?;
355 this.write_scalar(var, place.into())?;
359 this.machine.env_vars.environ.unwrap().into(),