src/shims/windows/foreign_items.rs

   1 use std::iter;
   2
   3 use rustc_middle::mir;
   4 use rustc_target::abi::Size;
   5
   6 use crate::*;
   7 use helpers::check_arg_count;
   8
   9 impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
  10 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
  11     fn emulate_foreign_item_by_name(
  12         &mut self,
  13         link_name: &str,
  14         args: &[OpTy<'tcx, Tag>],
  15         dest: PlaceTy<'tcx, Tag>,
  16         _ret: mir::BasicBlock,
  17     ) -> InterpResult<'tcx, bool> {
  18         let this = self.eval_context_mut();
  19
  20         // Windows API stubs.
  21         // HANDLE = isize
  22         // DWORD = ULONG = u32
  23         // BOOL = i32
  24         // BOOLEAN = u8
  25         match link_name {
  26             // Environment related shims
  27             "GetEnvironmentVariableW" => {
  28                 let &[name, buf, size] = check_arg_count(args)?;
  29                 let result = this.GetEnvironmentVariableW(name, buf, size)?;
  30                 this.write_scalar(Scalar::from_u32(result), dest)?;
  31             }
  32             "SetEnvironmentVariableW" => {
  33                 let &[name, value] = check_arg_count(args)?;
  34                 let result = this.SetEnvironmentVariableW(name, value)?;
  35                 this.write_scalar(Scalar::from_i32(result), dest)?;
  36             }
  37             "GetEnvironmentStringsW" => {
  38                 let &[] = check_arg_count(args)?;
  39                 let result = this.GetEnvironmentStringsW()?;
  40                 this.write_scalar(result, dest)?;
  41             }
  42             "FreeEnvironmentStringsW" => {
  43                 let &[env_block] = check_arg_count(args)?;
  44                 let result = this.FreeEnvironmentStringsW(env_block)?;
  45                 this.write_scalar(Scalar::from_i32(result), dest)?;
  46             }
  47             "GetCurrentDirectoryW" => {
  48                 let &[size, buf] = check_arg_count(args)?;
  49                 let result = this.GetCurrentDirectoryW(size, buf)?;
  50                 this.write_scalar(Scalar::from_u32(result), dest)?;
  51             }
  52             "SetCurrentDirectoryW" => {
  53                 let &[path] = check_arg_count(args)?;
  54                 let result = this.SetCurrentDirectoryW(path)?;
  55                 this.write_scalar(Scalar::from_i32(result), dest)?;
  56             }
  57
  58             // File related shims
  59             "GetStdHandle" => {
  60                 let &[which] = check_arg_count(args)?;
  61                 let which = this.read_scalar(which)?.to_i32()?;
  62                 // We just make this the identity function, so we know later in `WriteFile`
  63                 // which one it is.
  64                 this.write_scalar(Scalar::from_machine_isize(which.into(), this), dest)?;
  65             }
  66             "WriteFile" => {
  67                 let &[handle, buf, n, written_ptr, overlapped] = check_arg_count(args)?;
  68                 this.read_scalar(overlapped)?.to_machine_usize(this)?; // this is a poiner, that we ignore
  69                 let handle = this.read_scalar(handle)?.to_machine_isize(this)?;
  70                 let buf = this.read_scalar(buf)?.check_init()?;
  71                 let n = this.read_scalar(n)?.to_u32()?;
  72                 let written_place = this.deref_operand(written_ptr)?;
  73                 // Spec says to always write `0` first.
  74                 this.write_null(written_place.into())?;
  75                 let written = if handle == -11 || handle == -12 {
  76                     // stdout/stderr
  77                     use std::io::{self, Write};
  78
  79                     let buf_cont = this.memory.read_bytes(buf, Size::from_bytes(u64::from(n)))?;
  80                     let res = if handle == -11 {
  81                         io::stdout().write(buf_cont)
  82                     } else {
  83                         io::stderr().write(buf_cont)
  84                     };
  85                     res.ok().map(|n| n as u32)
  86                 } else {
  87                     throw_unsup_format!("on Windows, writing to anything except stdout/stderr is not supported")
  88                 };
  89                 // If there was no error, write back how much was written.
  90                 if let Some(n) = written {
  91                     this.write_scalar(Scalar::from_u32(n), written_place.into())?;
  92                 }
  93                 // Return whether this was a success.
  94                 this.write_scalar(
  95                     Scalar::from_i32(if written.is_some() { 1 } else { 0 }),
  96                     dest,
  97                 )?;
  98             }
  99
 100             // Allocation
 101             "HeapAlloc" => {
 102                 let &[handle, flags, size] = check_arg_count(args)?;
 103                 this.read_scalar(handle)?.to_machine_isize(this)?;
 104                 let flags = this.read_scalar(flags)?.to_u32()?;
 105                 let size = this.read_scalar(size)?.to_machine_usize(this)?;
 106                 let zero_init = (flags & 0x00000008) != 0; // HEAP_ZERO_MEMORY
 107                 let res = this.malloc(size, zero_init, MiriMemoryKind::WinHeap);
 108                 this.write_scalar(res, dest)?;
 109             }
 110             "HeapFree" => {
 111                 let &[handle, flags, ptr] = check_arg_count(args)?;
 112                 this.read_scalar(handle)?.to_machine_isize(this)?;
 113                 this.read_scalar(flags)?.to_u32()?;
 114                 let ptr = this.read_scalar(ptr)?.check_init()?;
 115                 this.free(ptr, MiriMemoryKind::WinHeap)?;
 116                 this.write_scalar(Scalar::from_i32(1), dest)?;
 117             }
 118             "HeapReAlloc" => {
 119                 let &[handle, flags, ptr, size] = check_arg_count(args)?;
 120                 this.read_scalar(handle)?.to_machine_isize(this)?;
 121                 this.read_scalar(flags)?.to_u32()?;
 122                 let ptr = this.read_scalar(ptr)?.check_init()?;
 123                 let size = this.read_scalar(size)?.to_machine_usize(this)?;
 124                 let res = this.realloc(ptr, size, MiriMemoryKind::WinHeap)?;
 125                 this.write_scalar(res, dest)?;
 126             }
 127
 128             // errno
 129             "SetLastError" => {
 130                 let &[error] = check_arg_count(args)?;
 131                 let error = this.read_scalar(error)?.check_init()?;
 132                 this.set_last_error(error)?;
 133             }
 134             "GetLastError" => {
 135                 let &[] = check_arg_count(args)?;
 136                 let last_error = this.get_last_error()?;
 137                 this.write_scalar(last_error, dest)?;
 138             }
 139
 140             // Querying system information
 141             "GetSystemInfo" => {
 142                 let &[system_info] = check_arg_count(args)?;
 143                 let system_info = this.deref_operand(system_info)?;
 144                 // Initialize with `0`.
 145                 this.memory.write_bytes(
 146                     system_info.ptr,
 147                     iter::repeat(0u8).take(system_info.layout.size.bytes() as usize),
 148                 )?;
 149                 // Set number of processors.
 150                 let dword_size = Size::from_bytes(4);
 151                 let num_cpus = this.mplace_field(system_info, 6)?;
 152                 this.write_scalar(Scalar::from_int(NUM_CPUS, dword_size), num_cpus.into())?;
 153             }
 154
 155             // Thread-local storage
 156             "TlsAlloc" => {
 157                 // This just creates a key; Windows does not natively support TLS destructors.
 158
 159                 // Create key and return it.
 160                 let &[] = check_arg_count(args)?;
 161                 let key = this.machine.tls.create_tls_key(None, dest.layout.size)?;
 162                 this.write_scalar(Scalar::from_uint(key, dest.layout.size), dest)?;
 163             }
 164             "TlsGetValue" => {
 165                 let &[key] = check_arg_count(args)?;
 166                 let key = u128::from(this.read_scalar(key)?.to_u32()?);
 167                 let active_thread = this.get_active_thread();
 168                 let ptr = this.machine.tls.load_tls(key, active_thread, this)?;
 169                 this.write_scalar(ptr, dest)?;
 170             }
 171             "TlsSetValue" => {
 172                 let &[key, new_ptr] = check_arg_count(args)?;
 173                 let key = u128::from(this.read_scalar(key)?.to_u32()?);
 174                 let active_thread = this.get_active_thread();
 175                 let new_ptr = this.read_scalar(new_ptr)?.check_init()?;
 176                 this.machine.tls.store_tls(key, active_thread, this.test_null(new_ptr)?)?;
 177
 178                 // Return success (`1`).
 179                 this.write_scalar(Scalar::from_i32(1), dest)?;
 180             }
 181
 182             // Access to command-line arguments
 183             "GetCommandLineW" => {
 184                 let &[] = check_arg_count(args)?;
 185                 this.write_scalar(
 186                     this.machine.cmd_line.expect("machine must be initialized"),
 187                     dest,
 188                 )?;
 189             }
 190
 191             // Time related shims
 192             "GetSystemTimeAsFileTime" => {
 193                 #[allow(non_snake_case)]
 194                 let &[LPFILETIME] = check_arg_count(args)?;
 195                 this.GetSystemTimeAsFileTime(LPFILETIME)?;
 196             }
 197             "QueryPerformanceCounter" => {
 198                 #[allow(non_snake_case)]
 199                 let &[lpPerformanceCount] = check_arg_count(args)?;
 200                 let result = this.QueryPerformanceCounter(lpPerformanceCount)?;
 201                 this.write_scalar(Scalar::from_i32(result), dest)?;
 202             }
 203             "QueryPerformanceFrequency" => {
 204                 #[allow(non_snake_case)]
 205                 let &[lpFrequency] = check_arg_count(args)?;
 206                 let result = this.QueryPerformanceFrequency(lpFrequency)?;
 207                 this.write_scalar(Scalar::from_i32(result), dest)?;
 208             }
 209
 210             // Dynamic symbol loading
 211             "GetProcAddress" => {
 212                 #[allow(non_snake_case)]
 213                 let &[hModule, lpProcName] = check_arg_count(args)?;
 214                 this.read_scalar(hModule)?.to_machine_isize(this)?;
 215                 let name = this.memory.read_c_str(this.read_scalar(lpProcName)?.check_init()?)?;
 216                 if let Some(dlsym) = Dlsym::from_str(name, &this.tcx.sess.target.target.target_os)? {
 217                     let ptr = this.memory.create_fn_alloc(FnVal::Other(dlsym));
 218                     this.write_scalar(Scalar::from(ptr), dest)?;
 219                 } else {
 220                     this.write_null(dest)?;
 221                 }
 222             }
 223
 224             // Miscellaneous
 225             "SystemFunction036" => {
 226                 // The actual name of 'RtlGenRandom'
 227                 let &[ptr, len] = check_arg_count(args)?;
 228                 let ptr = this.read_scalar(ptr)?.check_init()?;
 229                 let len = this.read_scalar(len)?.to_u32()?;
 230                 this.gen_random(ptr, len.into())?;
 231                 this.write_scalar(Scalar::from_bool(true), dest)?;
 232             }
 233             "GetConsoleScreenBufferInfo" => {
 234                 // `term` needs this, so we fake it.
 235                 let &[console, buffer_info] = check_arg_count(args)?;
 236                 this.read_scalar(console)?.to_machine_isize(this)?;
 237                 this.deref_operand(buffer_info)?;
 238                 // Indicate an error.
 239                 // FIXME: we should set last_error, but to what?
 240                 this.write_null(dest)?;
 241             }
 242             "GetConsoleMode" => {
 243                 // Windows "isatty" (in libtest) needs this, so we fake it.
 244                 let &[console, mode] = check_arg_count(args)?;
 245                 this.read_scalar(console)?.to_machine_isize(this)?;
 246                 this.deref_operand(mode)?;
 247                 // Indicate an error.
 248                 // FIXME: we should set last_error, but to what?
 249                 this.write_null(dest)?;
 250             }
 251             "SwitchToThread" => {
 252                 let &[] = check_arg_count(args)?;
 253                 // Note that once Miri supports concurrency, this will need to return a nonzero
 254                 // value if this call does result in switching to another thread.
 255                 this.write_null(dest)?;
 256             }
 257
 258             // Better error for attempts to create a thread
 259             "CreateThread" => {
 260                 throw_unsup_format!("Miri does not support concurrency on Windows");
 261             }
 262
 263             // Incomplete shims that we "stub out" just to get pre-main initialization code to work.
 264             // These shims are enabled only when the caller is in the standard library.
 265             "GetProcessHeap" if this.frame().instance.to_string().starts_with("std::sys::windows::") => {
 266                 let &[] = check_arg_count(args)?;
 267                 // Just fake a HANDLE
 268                 this.write_scalar(Scalar::from_machine_isize(1, this), dest)?;
 269             }
 270             "GetModuleHandleW" if this.frame().instance.to_string().starts_with("std::sys::windows::") => {
 271                 #[allow(non_snake_case)]
 272                 let &[_lpModuleName] = check_arg_count(args)?;
 273                 // Pretend this does not exist / nothing happened, by returning zero.
 274                 this.write_null(dest)?;
 275             }
 276             "SetConsoleTextAttribute" if this.frame().instance.to_string().starts_with("std::sys::windows::") => {
 277                 #[allow(non_snake_case)]
 278                 let &[_hConsoleOutput, _wAttribute] = check_arg_count(args)?;
 279                 // Pretend these does not exist / nothing happened, by returning zero.
 280                 this.write_null(dest)?;
 281             }
 282             "AddVectoredExceptionHandler" if this.frame().instance.to_string().starts_with("std::sys::windows::") => {
 283                 #[allow(non_snake_case)]
 284                 let &[_First, _Handler] = check_arg_count(args)?;
 285                 // Any non zero value works for the stdlib. This is just used for stack overflows anyway.
 286                 this.write_scalar(Scalar::from_machine_usize(1, this), dest)?;
 287             }
 288             | "InitializeCriticalSection"
 289             | "EnterCriticalSection"
 290             | "LeaveCriticalSection"
 291             | "DeleteCriticalSection"
 292             if this.frame().instance.to_string().starts_with("std::sys::windows::") => {
 293                 #[allow(non_snake_case)]
 294                 let &[_lpCriticalSection] = check_arg_count(args)?;
 295                 assert_eq!(this.get_total_thread_count(), 1, "concurrency on Windows is not supported");
 296                 // Nothing to do, not even a return value.
 297                 // (Windows locks are reentrant, and we have only 1 thread,
 298                 // so not doing any futher checks here is at least not incorrect.)
 299             }
 300             "TryEnterCriticalSection"
 301             if this.frame().instance.to_string().starts_with("std::sys::windows::") => {
 302                 #[allow(non_snake_case)]
 303                 let &[_lpCriticalSection] = check_arg_count(args)?;
 304                 assert_eq!(this.get_total_thread_count(), 1, "concurrency on Windows is not supported");
 305                 // There is only one thread, so this always succeeds and returns TRUE.
 306                 this.write_scalar(Scalar::from_i32(1), dest)?;
 307             }
 308
 309             _ => throw_unsup_format!("can't call foreign function: {}", link_name),
 310         }
 311
 312         Ok(true)
 313     }
 314 }
 315