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_middle::ty::layout::Size;
11 use rustc_mir::interpret::Pointer;
13 /// Check whether an operation that writes to a target buffer was successful.
14 /// Accordingly select return value.
15 /// Local helper function to be used in Windows shims.
16 fn windows_check_buffer_size((success, len): (bool, u64)) -> u32 {
18 // If the function succeeds, the return value is the number of characters stored in the target buffer,
19 // not including the terminating null character.
20 u32::try_from(len).unwrap()
22 // If the target buffer was not large enough to hold the data, the return value is the buffer size, in characters,
23 // required to hold the string and its terminating null character.
24 u32::try_from(len.checked_add(1).unwrap()).unwrap()
29 pub struct EnvVars<'tcx> {
30 /// Stores pointers to the environment variables. These variables must be stored as
31 /// null-terminated target strings (c_str or wide_str) with the `"{name}={value}"` format.
32 map: FxHashMap<OsString, Pointer<Tag>>,
34 /// Place where the `environ` static is stored. Lazily initialized, but then never changes.
35 pub(crate) environ: Option<MPlaceTy<'tcx, Tag>>,
38 impl<'tcx> EnvVars<'tcx> {
39 pub(crate) fn init<'mir>(
40 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
41 mut excluded_env_vars: Vec<String>,
42 ) -> InterpResult<'tcx> {
43 let target_os = ecx.tcx.sess.target.target.target_os.as_str();
44 if target_os == "windows" {
45 // Temporary hack: Exclude `TERM` var to avoid terminfo trying to open the termcap file.
46 // Can be removed once https://github.com/rust-lang/miri/issues/1013 is resolved.
47 excluded_env_vars.push("TERM".to_owned());
50 if ecx.machine.communicate {
51 for (name, value) in env::vars() {
52 if !excluded_env_vars.contains(&name) {
53 let var_ptr = match target_os {
54 "linux" | "macos" => alloc_env_var_as_c_str(name.as_ref(), value.as_ref(), ecx)?,
55 "windows" => alloc_env_var_as_wide_str(name.as_ref(), value.as_ref(), ecx)?,
56 unsupported => throw_unsup_format!("environment support for target OS `{}` not yet available", unsupported),
58 ecx.machine.env_vars.map.insert(OsString::from(name), var_ptr);
65 pub(crate) fn cleanup<'mir>(
66 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
67 ) -> InterpResult<'tcx> {
68 // Deallocate individual env vars.
69 for (_name, ptr) in ecx.machine.env_vars.map.drain() {
70 ecx.memory.deallocate(ptr, None, MiriMemoryKind::Env.into())?;
72 // Deallocate environ var list.
73 let environ = ecx.machine.env_vars.environ.unwrap();
74 let old_vars_ptr = ecx.read_scalar(environ.into())?.not_undef()?;
75 ecx.memory.deallocate(ecx.force_ptr(old_vars_ptr)?, None, MiriMemoryKind::Env.into())?;
80 fn alloc_env_var_as_c_str<'mir, 'tcx>(
83 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
84 ) -> InterpResult<'tcx, Pointer<Tag>> {
85 let mut name_osstring = name.to_os_string();
86 name_osstring.push("=");
87 name_osstring.push(value);
88 Ok(ecx.alloc_os_str_as_c_str(name_osstring.as_os_str(), MiriMemoryKind::Env.into()))
91 fn alloc_env_var_as_wide_str<'mir, 'tcx>(
94 ecx: &mut InterpCx<'mir, 'tcx, Evaluator<'tcx>>,
95 ) -> InterpResult<'tcx, Pointer<Tag>> {
96 let mut name_osstring = name.to_os_string();
97 name_osstring.push("=");
98 name_osstring.push(value);
99 Ok(ecx.alloc_os_str_as_wide_str(name_osstring.as_os_str(), MiriMemoryKind::Env.into()))
102 impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
103 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
104 fn getenv(&mut self, name_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, Scalar<Tag>> {
105 let this = self.eval_context_mut();
106 let target_os = &this.tcx.sess.target.target.target_os;
107 assert!(target_os == "linux" || target_os == "macos", "`getenv` is only available for the UNIX target family");
109 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
110 let name = this.read_os_str_from_c_str(name_ptr)?;
111 Ok(match this.machine.env_vars.map.get(name) {
113 // The offset is used to strip the "{name}=" part of the string.
114 Scalar::from(var_ptr.offset(Size::from_bytes(u64::try_from(name.len()).unwrap().checked_add(1).unwrap()), this)?)
116 None => Scalar::null_ptr(&*this.tcx),
120 #[allow(non_snake_case)]
121 fn GetEnvironmentVariableW(
123 name_op: OpTy<'tcx, Tag>, // LPCWSTR
124 buf_op: OpTy<'tcx, Tag>, // LPWSTR
125 size_op: OpTy<'tcx, Tag>, // DWORD
126 ) -> InterpResult<'tcx, u32> { // Returns DWORD (u32 in Windows)
127 let this = self.eval_context_mut();
128 this.assert_target_os("windows", "GetEnvironmentVariableW");
130 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
131 let name = this.read_os_str_from_wide_str(name_ptr)?;
132 Ok(match this.machine.env_vars.map.get(&name) {
134 // The offset is used to strip the "{name}=" part of the string.
135 let name_offset_bytes =
136 u64::try_from(name.len()).unwrap().checked_add(1).unwrap().checked_mul(2).unwrap();
137 let var_ptr = Scalar::from(var_ptr.offset(Size::from_bytes(name_offset_bytes), this)?);
138 let var = this.read_os_str_from_wide_str(var_ptr)?;
140 let buf_ptr = this.read_scalar(buf_op)?.not_undef()?;
141 // `buf_size` represents the size in characters.
142 let buf_size = u64::from(this.read_scalar(size_op)?.to_u32()?);
143 windows_check_buffer_size(this.write_os_str_to_wide_str(&var, buf_ptr, buf_size)?)
146 let envvar_not_found = this.eval_windows("ERROR_ENVVAR_NOT_FOUND")?;
147 this.set_last_error(envvar_not_found)?;
148 0 // return zero upon failure
153 #[allow(non_snake_case)]
154 fn GetEnvironmentStringsW(&mut self) -> InterpResult<'tcx, Scalar<Tag>> {
155 let this = self.eval_context_mut();
156 this.assert_target_os("windows", "GetEnvironmentStringsW");
158 // Info on layout of environment blocks in Windows:
159 // https://docs.microsoft.com/en-us/windows/win32/procthread/environment-variables
160 let mut env_vars = std::ffi::OsString::new();
161 for &item in this.machine.env_vars.map.values() {
162 let env_var = this.read_os_str_from_wide_str(Scalar::from(item))?;
163 env_vars.push(env_var);
166 // Allocate environment block & Store environment variables to environment block.
167 // Final null terminator(block terminator) is added by `alloc_os_str_to_wide_str`.
168 // FIXME: MemoryKind should be `Env`, blocked on https://github.com/rust-lang/rust/pull/70479.
169 let envblock_ptr = this.alloc_os_str_as_wide_str(&env_vars, MiriMemoryKind::WinHeap.into());
170 // If the function succeeds, the return value is a pointer to the environment block of the current process.
171 Ok(envblock_ptr.into())
174 #[allow(non_snake_case)]
175 fn FreeEnvironmentStringsW(&mut self, env_block_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
176 let this = self.eval_context_mut();
177 this.assert_target_os("windows", "FreeEnvironmentStringsW");
179 let env_block_ptr = this.read_scalar(env_block_op)?.not_undef()?;
180 // FIXME: MemoryKind should be `Env`, blocked on https://github.com/rust-lang/rust/pull/70479.
181 let result = this.memory.deallocate(this.force_ptr(env_block_ptr)?, None, MiriMemoryKind::WinHeap.into());
182 // If the function succeeds, the return value is nonzero.
183 Ok(result.is_ok() as i32)
188 name_op: OpTy<'tcx, Tag>,
189 value_op: OpTy<'tcx, Tag>,
190 ) -> InterpResult<'tcx, i32> {
191 let mut this = self.eval_context_mut();
192 let target_os = &this.tcx.sess.target.target.target_os;
193 assert!(target_os == "linux" || target_os == "macos", "`setenv` is only available for the UNIX target family");
195 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
196 let value_ptr = this.read_scalar(value_op)?.not_undef()?;
199 if !this.is_null(name_ptr)? {
200 let name = this.read_os_str_from_c_str(name_ptr)?;
201 if !name.is_empty() && !name.to_string_lossy().contains('=') {
202 let value = this.read_os_str_from_c_str(value_ptr)?;
203 new = Some((name.to_owned(), value.to_owned()));
206 if let Some((name, value)) = new {
207 let var_ptr = alloc_env_var_as_c_str(&name, &value, &mut this)?;
208 if let Some(var) = this.machine.env_vars.map.insert(name, var_ptr) {
210 .deallocate(var, None, MiriMemoryKind::Env.into())?;
212 this.update_environ()?;
213 Ok(0) // return zero on success
215 // name argument is a null pointer, points to an empty string, or points to a string containing an '=' character.
216 let einval = this.eval_libc("EINVAL")?;
217 this.set_last_error(einval)?;
222 #[allow(non_snake_case)]
223 fn SetEnvironmentVariableW(
225 name_op: OpTy<'tcx, Tag>, // LPCWSTR
226 value_op: OpTy<'tcx, Tag>, // LPCWSTR
227 ) -> InterpResult<'tcx, i32> {
228 let mut this = self.eval_context_mut();
229 this.assert_target_os("windows", "SetEnvironmentVariableW");
231 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
232 let value_ptr = this.read_scalar(value_op)?.not_undef()?;
234 if this.is_null(name_ptr)? {
235 // ERROR CODE is not clearly explained in docs.. For now, throw UB instead.
236 throw_ub_format!("pointer to environment variable name is NULL");
239 let name = this.read_os_str_from_wide_str(name_ptr)?;
241 throw_unsup_format!("environment variable name is an empty string");
242 } else if name.to_string_lossy().contains('=') {
243 throw_unsup_format!("environment variable name contains '='");
244 } else if this.is_null(value_ptr)? {
245 // Delete environment variable `{name}`
246 if let Some(var) = this.machine.env_vars.map.remove(&name) {
247 this.memory.deallocate(var, None, MiriMemoryKind::Env.into())?;
248 this.update_environ()?;
250 Ok(1) // return non-zero on success
252 let value = this.read_os_str_from_wide_str(value_ptr)?;
253 let var_ptr = alloc_env_var_as_wide_str(&name, &value, &mut this)?;
254 if let Some(var) = this.machine.env_vars.map.insert(name, var_ptr) {
256 .deallocate(var, None, MiriMemoryKind::Env.into())?;
258 this.update_environ()?;
259 Ok(1) // return non-zero on success
263 fn unsetenv(&mut self, name_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
264 let this = self.eval_context_mut();
265 let target_os = &this.tcx.sess.target.target.target_os;
266 assert!(target_os == "linux" || target_os == "macos", "`unsetenv` is only available for the UNIX target family");
268 let name_ptr = this.read_scalar(name_op)?.not_undef()?;
269 let mut success = None;
270 if !this.is_null(name_ptr)? {
271 let name = this.read_os_str_from_c_str(name_ptr)?.to_owned();
272 if !name.is_empty() && !name.to_string_lossy().contains('=') {
273 success = Some(this.machine.env_vars.map.remove(&name));
276 if let Some(old) = success {
277 if let Some(var) = old {
279 .deallocate(var, None, MiriMemoryKind::Env.into())?;
281 this.update_environ()?;
284 // name argument is a null pointer, points to an empty string, or points to a string containing an '=' character.
285 let einval = this.eval_libc("EINVAL")?;
286 this.set_last_error(einval)?;
293 buf_op: OpTy<'tcx, Tag>,
294 size_op: OpTy<'tcx, Tag>,
295 ) -> InterpResult<'tcx, Scalar<Tag>> {
296 let this = self.eval_context_mut();
297 let target_os = &this.tcx.sess.target.target.target_os;
298 assert!(target_os == "linux" || target_os == "macos", "`getcwd` is only available for the UNIX target family");
300 this.check_no_isolation("getcwd")?;
302 let buf = this.read_scalar(buf_op)?.not_undef()?;
303 let size = this.read_scalar(size_op)?.to_machine_usize(&*this.tcx)?;
304 // If we cannot get the current directory, we return null
305 match env::current_dir() {
307 if this.write_path_to_c_str(&cwd, buf, size)?.0 {
310 let erange = this.eval_libc("ERANGE")?;
311 this.set_last_error(erange)?;
313 Err(e) => this.set_last_error_from_io_error(e)?,
315 Ok(Scalar::null_ptr(&*this.tcx))
318 #[allow(non_snake_case)]
319 fn GetCurrentDirectoryW(
321 size_op: OpTy<'tcx, Tag>, // DWORD
322 buf_op: OpTy<'tcx, Tag>, // LPTSTR
323 ) -> InterpResult<'tcx, u32> {
324 let this = self.eval_context_mut();
325 this.assert_target_os("windows", "GetCurrentDirectoryW");
327 this.check_no_isolation("GetCurrentDirectoryW")?;
329 let size = u64::from(this.read_scalar(size_op)?.to_u32()?);
330 let buf = this.read_scalar(buf_op)?.not_undef()?;
332 // If we cannot get the current directory, we return 0
333 match env::current_dir() {
335 return Ok(windows_check_buffer_size(this.write_path_to_wide_str(&cwd, buf, size)?)),
336 Err(e) => this.set_last_error_from_io_error(e)?,
341 fn chdir(&mut self, path_op: OpTy<'tcx, Tag>) -> InterpResult<'tcx, i32> {
342 let this = self.eval_context_mut();
343 let target_os = &this.tcx.sess.target.target.target_os;
344 assert!(target_os == "linux" || target_os == "macos", "`getcwd` is only available for the UNIX target family");
346 this.check_no_isolation("chdir")?;
348 let path = this.read_path_from_c_str(this.read_scalar(path_op)?.not_undef()?)?;
350 match env::set_current_dir(path) {
353 this.set_last_error_from_io_error(e)?;
359 #[allow(non_snake_case)]
360 fn SetCurrentDirectoryW (
362 path_op: OpTy<'tcx, Tag> // LPCTSTR
363 ) -> InterpResult<'tcx, i32> { // Returns BOOL (i32 in Windows)
364 let this = self.eval_context_mut();
365 this.assert_target_os("windows", "SetCurrentDirectoryW");
367 this.check_no_isolation("SetCurrentDirectoryW")?;
369 let path = this.read_path_from_wide_str(this.read_scalar(path_op)?.not_undef()?)?;
371 match env::set_current_dir(path) {
374 this.set_last_error_from_io_error(e)?;
380 /// Updates the `environ` static.
381 /// The first time it gets called, also initializes `extra.environ`.
382 fn update_environ(&mut self) -> InterpResult<'tcx> {
383 let this = self.eval_context_mut();
384 // Deallocate the old environ list, if any.
385 if let Some(environ) = this.machine.env_vars.environ {
386 let old_vars_ptr = this.read_scalar(environ.into())?.not_undef()?;
387 this.memory.deallocate(this.force_ptr(old_vars_ptr)?, None, MiriMemoryKind::Env.into())?;
389 // No `environ` allocated yet, let's do that.
390 // This is memory backing an extern static, hence `Machine`, not `Env`.
391 let layout = this.layout_of(this.tcx.types.usize)?;
392 let place = this.allocate(layout, MiriMemoryKind::Machine.into());
393 this.machine.env_vars.environ = Some(place);
396 // Collect all the pointers to each variable in a vector.
397 let mut vars: Vec<Scalar<Tag>> = this.machine.env_vars.map.values().map(|&ptr| ptr.into()).collect();
398 // Add the trailing null pointer.
399 vars.push(Scalar::null_ptr(this));
400 // Make an array with all these pointers inside Miri.
403 this.layout_of(tcx.mk_array(tcx.types.usize, u64::try_from(vars.len()).unwrap()))?;
404 let vars_place = this.allocate(vars_layout, MiriMemoryKind::Env.into());
405 for (idx, var) in vars.into_iter().enumerate() {
406 let place = this.mplace_field(vars_place, idx)?;
407 this.write_scalar(var, place.into())?;
411 this.machine.env_vars.environ.unwrap().into(),