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.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::null_ptr(&*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, u32> { // Returns DWORD (u32 in Windows)
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::from(this.read_scalar(size_op)?.to_u32()?);
128 windows_check_buffer_size(this.write_os_str_to_wide_str(&var, buf_ptr, buf_size)?)
131 let envvar_not_found = this.eval_windows("ERROR_ENVVAR_NOT_FOUND")?;
132 this.set_last_error(envvar_not_found)?;
133 0 // return zero upon failure
138 #[allow(non_snake_case)]
139 fn GetEnvironmentStringsW(&mut self) -> InterpResult<'tcx, Scalar<Tag>> {
140 let this = self.eval_context_mut();
141 this.assert_target_os("windows", "GetEnvironmentStringsW");
143 // Info on layout of environment blocks in Windows:
144 // https://docs.microsoft.com/en-us/windows/win32/procthread/environment-variables
145 let mut env_vars = std::ffi::OsString::new();
146 for &item in this.machine.env_vars.map.values() {
147 let env_var = this.read_os_str_from_wide_str(Scalar::from(item))?;
148 env_vars.push(env_var);
151 // Allocate environment block & Store environment variables to environment block.
152 // Final null terminator(block terminator) is added by `alloc_os_str_to_wide_str`.
153 // FIXME: MemoryKind should be `Env`, blocked on https://github.com/rust-lang/rust/pull/70479.
154 let envblock_ptr = this.alloc_os_str_as_wide_str(&env_vars, MiriMemoryKind::WinHeap.into());
155 // If the function succeeds, the return value is a pointer to the environment block of the current process.
156 Ok(envblock_ptr.into())
159 #[allow(non_snake_case)]
160 fn FreeEnvironmentStringsW(&mut self, env_block_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
161 let this = self.eval_context_mut();
162 this.assert_target_os("windows", "FreeEnvironmentStringsW");
164 let env_block_ptr = this.read_scalar(env_block_op)?.not_undef()?;
165 // FIXME: MemoryKind should be `Env`, blocked on https://github.com/rust-lang/rust/pull/70479.
166 let result = this.memory.deallocate(this.force_ptr(env_block_ptr)?, None, MiriMemoryKind::WinHeap.into());
167 // If the function succeeds, the return value is nonzero.
168 Ok(result.is_ok() as i32)
173 name_op: OpTy<'tcx, Tag>,
174 value_op: OpTy<'tcx, Tag>,
175 ) -> InterpResult<'tcx, i32> {
176 let mut this = self.eval_context_mut();
177 let target_os = &this.tcx.sess.target.target.target_os;
178 assert!(target_os == "linux" || target_os == "macos", "`setenv` is only available for the UNIX target family");
180 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
181 let value_ptr = this.read_scalar(value_op)?.not_undef()?;
184 if !this.is_null(name_ptr)? {
185 let name = this.read_os_str_from_c_str(name_ptr)?;
186 if !name.is_empty() && !name.to_string_lossy().contains('=') {
187 let value = this.read_os_str_from_c_str(value_ptr)?;
188 new = Some((name.to_owned(), value.to_owned()));
191 if let Some((name, value)) = new {
192 let var_ptr = alloc_env_var_as_c_str(&name, &value, &mut this)?;
193 if let Some(var) = this.machine.env_vars.map.insert(name, var_ptr) {
195 .deallocate(var, None, MiriMemoryKind::Env.into())?;
197 this.update_environ()?;
198 Ok(0) // return zero on success
200 // name argument is a null pointer, points to an empty string, or points to a string containing an '=' character.
201 let einval = this.eval_libc("EINVAL")?;
202 this.set_last_error(einval)?;
207 #[allow(non_snake_case)]
208 fn SetEnvironmentVariableW(
210 name_op: OpTy<'tcx, Tag>, // LPCWSTR
211 value_op: OpTy<'tcx, Tag>, // LPCWSTR
212 ) -> InterpResult<'tcx, i32> {
213 let mut this = self.eval_context_mut();
214 this.assert_target_os("windows", "SetEnvironmentVariableW");
216 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
217 let value_ptr = this.read_scalar(value_op)?.not_undef()?;
219 if this.is_null(name_ptr)? {
220 // ERROR CODE is not clearly explained in docs.. For now, throw UB instead.
221 throw_ub_format!("pointer to environment variable name is NULL");
224 let name = this.read_os_str_from_wide_str(name_ptr)?;
226 throw_unsup_format!("environment variable name is an empty string");
227 } else if name.to_string_lossy().contains('=') {
228 throw_unsup_format!("environment variable name contains '='");
229 } else if this.is_null(value_ptr)? {
230 // Delete environment variable `{name}`
231 if let Some(var) = this.machine.env_vars.map.remove(&name) {
232 this.memory.deallocate(var, None, MiriMemoryKind::Env.into())?;
233 this.update_environ()?;
235 Ok(1) // return non-zero on success
237 let value = this.read_os_str_from_wide_str(value_ptr)?;
238 let var_ptr = alloc_env_var_as_wide_str(&name, &value, &mut this)?;
239 if let Some(var) = this.machine.env_vars.map.insert(name, var_ptr) {
241 .deallocate(var, None, MiriMemoryKind::Env.into())?;
243 this.update_environ()?;
244 Ok(1) // return non-zero on success
248 fn unsetenv(&mut self, name_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
249 let this = self.eval_context_mut();
250 let target_os = &this.tcx.sess.target.target.target_os;
251 assert!(target_os == "linux" || target_os == "macos", "`unsetenv` is only available for the UNIX target family");
253 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
254 let mut success = None;
255 if !this.is_null(name_ptr)? {
256 let name = this.read_os_str_from_c_str(name_ptr)?.to_owned();
257 if !name.is_empty() && !name.to_string_lossy().contains('=') {
258 success = Some(this.machine.env_vars.map.remove(&name));
261 if let Some(old) = success {
262 if let Some(var) = old {
264 .deallocate(var, None, MiriMemoryKind::Env.into())?;
266 this.update_environ()?;
269 // name argument is a null pointer, points to an empty string, or points to a string containing an '=' character.
270 let einval = this.eval_libc("EINVAL")?;
271 this.set_last_error(einval)?;
278 buf_op: OpTy<'tcx, Tag>,
279 size_op: OpTy<'tcx, Tag>,
280 ) -> InterpResult<'tcx, Scalar<Tag>> {
281 let this = self.eval_context_mut();
282 let target_os = &this.tcx.sess.target.target.target_os;
283 assert!(target_os == "linux" || target_os == "macos", "`getcwd` is only available for the UNIX target family");
285 this.check_no_isolation("getcwd")?;
287 let buf = this.read_scalar(buf_op)?.not_undef()?;
288 let size = this.read_scalar(size_op)?.to_machine_usize(&*this.tcx)?;
289 // If we cannot get the current directory, we return null
290 match env::current_dir() {
292 if this.write_path_to_c_str(&cwd, buf, size)?.0 {
295 let erange = this.eval_libc("ERANGE")?;
296 this.set_last_error(erange)?;
298 Err(e) => this.set_last_error_from_io_error(e)?,
300 Ok(Scalar::null_ptr(&*this.tcx))
303 #[allow(non_snake_case)]
304 fn GetCurrentDirectoryW(
306 size_op: OpTy<'tcx, Tag>, // DWORD
307 buf_op: OpTy<'tcx, Tag>, // LPTSTR
308 ) -> InterpResult<'tcx, u32> {
309 let this = self.eval_context_mut();
310 this.assert_target_os("windows", "GetCurrentDirectoryW");
312 this.check_no_isolation("GetCurrentDirectoryW")?;
314 let size = u64::from(this.read_scalar(size_op)?.to_u32()?);
315 let buf = this.read_scalar(buf_op)?.not_undef()?;
317 // If we cannot get the current directory, we return 0
318 match env::current_dir() {
320 return Ok(windows_check_buffer_size(this.write_path_to_wide_str(&cwd, buf, size)?)),
321 Err(e) => this.set_last_error_from_io_error(e)?,
326 fn chdir(&mut self, path_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
327 let this = self.eval_context_mut();
328 let target_os = &this.tcx.sess.target.target.target_os;
329 assert!(target_os == "linux" || target_os == "macos", "`getcwd` is only available for the UNIX target family");
331 this.check_no_isolation("chdir")?;
333 let path = this.read_path_from_c_str(this.read_scalar(path_op)?.not_undef()?)?;
335 match env::set_current_dir(path) {
338 this.set_last_error_from_io_error(e)?;
344 #[allow(non_snake_case)]
345 fn SetCurrentDirectoryW (
347 path_op: OpTy<'tcx, Tag> // LPCTSTR
348 ) -> InterpResult<'tcx, i32> { // Returns BOOL (i32 in Windows)
349 let this = self.eval_context_mut();
350 this.assert_target_os("windows", "SetCurrentDirectoryW");
352 this.check_no_isolation("SetCurrentDirectoryW")?;
354 let path = this.read_path_from_wide_str(this.read_scalar(path_op)?.not_undef()?)?;
356 match env::set_current_dir(path) {
359 this.set_last_error_from_io_error(e)?;
365 /// Updates the `environ` static.
366 /// The first time it gets called, also initializes `extra.environ`.
367 fn update_environ(&mut self) -> InterpResult<'tcx> {
368 let this = self.eval_context_mut();
369 // Deallocate the old environ list, if any.
370 if let Some(environ) = this.machine.env_vars.environ {
371 let old_vars_ptr = this.read_scalar(environ.into())?.not_undef()?;
372 this.memory.deallocate(this.force_ptr(old_vars_ptr)?, None, MiriMemoryKind::Env.into())?;
374 // No `environ` allocated yet, let's do that.
375 // This is memory backing an extern static, hence `Machine`, not `Env`.
376 let layout = this.layout_of(this.tcx.types.usize)?;
377 let place = this.allocate(layout, MiriMemoryKind::Machine.into());
378 this.machine.env_vars.environ = Some(place);
381 // Collect all the pointers to each variable in a vector.
382 let mut vars: Vec<Scalar<Tag>> = this.machine.env_vars.map.values().map(|&ptr| ptr.into()).collect();
383 // Add the trailing null pointer.
384 vars.push(Scalar::null_ptr(this));
385 // Make an array with all these pointers inside Miri.
388 this.layout_of(tcx.mk_array(tcx.types.usize, u64::try_from(vars.len()).unwrap()))?;
389 let vars_place = this.allocate(vars_layout, MiriMemoryKind::Env.into());
390 for (idx, var) in vars.into_iter().enumerate() {
391 let place = this.mplace_field(vars_place, idx)?;
392 this.write_scalar(var, place.into())?;
396 this.machine.env_vars.environ.unwrap().into(),
403 /// Check whether an operation that writes to a target buffer was successful.
404 /// Accordingly select return value.
405 /// Local helper function to be used in Windows shims.
406 fn windows_check_buffer_size((success, len): (bool, u64)) -> u32 {
408 // If the function succeeds, the return value is the number of characters stored in the target buffer,
409 // not including the terminating null character.
410 u32::try_from(len).unwrap()
412 // If the target buffer was not large enough to hold the data, the return value is the buffer size, in characters,
413 // required to hold the string and its terminating null character.
414 u32::try_from(len.checked_add(1).unwrap()).unwrap()