library/std/src/sys/solid/os.rs

   1 use super::unsupported;
   2 use crate::error::Error as StdError;
   3 use crate::ffi::{CStr, CString, OsStr, OsString};
   4 use crate::fmt;
   5 use crate::io;
   6 use crate::os::{
   7     raw::{c_char, c_int},
   8     solid::ffi::{OsStrExt, OsStringExt},
   9 };
  10 use crate::path::{self, PathBuf};
  11 use crate::sys_common::rwlock::StaticRWLock;
  12 use crate::vec;
  13
  14 use super::{abi, error, itron, memchr};
  15
  16 // `solid` directly maps `errno`s to μITRON error codes.
  17 impl itron::error::ItronError {
  18     #[inline]
  19     pub(crate) fn as_io_error(self) -> crate::io::Error {
  20         crate::io::Error::from_raw_os_error(self.as_raw())
  21     }
  22 }
  23
  24 pub fn errno() -> i32 {
  25     0
  26 }
  27
  28 pub fn error_string(errno: i32) -> String {
  29     if let Some(name) = error::error_name(errno) { name.to_owned() } else { format!("{errno}") }
  30 }
  31
  32 pub fn getcwd() -> io::Result<PathBuf> {
  33     unsupported()
  34 }
  35
  36 pub fn chdir(_: &path::Path) -> io::Result<()> {
  37     unsupported()
  38 }
  39
  40 pub struct SplitPaths<'a>(&'a !);
  41
  42 pub fn split_paths(_unparsed: &OsStr) -> SplitPaths<'_> {
  43     panic!("unsupported")
  44 }
  45
  46 impl<'a> Iterator for SplitPaths<'a> {
  47     type Item = PathBuf;
  48     fn next(&mut self) -> Option<PathBuf> {
  49         *self.0
  50     }
  51 }
  52
  53 #[derive(Debug)]
  54 pub struct JoinPathsError;
  55
  56 pub fn join_paths<I, T>(_paths: I) -> Result<OsString, JoinPathsError>
  57 where
  58     I: Iterator<Item = T>,
  59     T: AsRef<OsStr>,
  60 {
  61     Err(JoinPathsError)
  62 }
  63
  64 impl fmt::Display for JoinPathsError {
  65     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
  66         "not supported on this platform yet".fmt(f)
  67     }
  68 }
  69
  70 impl StdError for JoinPathsError {
  71     #[allow(deprecated)]
  72     fn description(&self) -> &str {
  73         "not supported on this platform yet"
  74     }
  75 }
  76
  77 pub fn current_exe() -> io::Result<PathBuf> {
  78     unsupported()
  79 }
  80
  81 static ENV_LOCK: StaticRWLock = StaticRWLock::new();
  82
  83 pub struct Env {
  84     iter: vec::IntoIter<(OsString, OsString)>,
  85 }
  86
  87 impl !Send for Env {}
  88 impl !Sync for Env {}
  89
  90 impl Iterator for Env {
  91     type Item = (OsString, OsString);
  92     fn next(&mut self) -> Option<(OsString, OsString)> {
  93         self.iter.next()
  94     }
  95     fn size_hint(&self) -> (usize, Option<usize>) {
  96         self.iter.size_hint()
  97     }
  98 }
  99
 100 /// Returns a vector of (variable, value) byte-vector pairs for all the
 101 /// environment variables of the current process.
 102 pub fn env() -> Env {
 103     extern "C" {
 104         static mut environ: *const *const c_char;
 105     }
 106
 107     unsafe {
 108         let _guard = ENV_LOCK.read();
 109         let mut result = Vec::new();
 110         if !environ.is_null() {
 111             while !(*environ).is_null() {
 112                 if let Some(key_value) = parse(CStr::from_ptr(*environ).to_bytes()) {
 113                     result.push(key_value);
 114                 }
 115                 environ = environ.add(1);
 116             }
 117         }
 118         return Env { iter: result.into_iter() };
 119     }
 120
 121     fn parse(input: &[u8]) -> Option<(OsString, OsString)> {
 122         // Strategy (copied from glibc): Variable name and value are separated
 123         // by an ASCII equals sign '='. Since a variable name must not be
 124         // empty, allow variable names starting with an equals sign. Skip all
 125         // malformed lines.
 126         if input.is_empty() {
 127             return None;
 128         }
 129         let pos = memchr::memchr(b'=', &input[1..]).map(|p| p + 1);
 130         pos.map(|p| {
 131             (
 132                 OsStringExt::from_vec(input[..p].to_vec()),
 133                 OsStringExt::from_vec(input[p + 1..].to_vec()),
 134             )
 135         })
 136     }
 137 }
 138
 139 pub fn getenv(k: &OsStr) -> Option<OsString> {
 140     // environment variables with a nul byte can't be set, so their value is
 141     // always None as well
 142     let k = CString::new(k.as_bytes()).ok()?;
 143     unsafe {
 144         let _guard = ENV_LOCK.read();
 145         let s = libc::getenv(k.as_ptr()) as *const libc::c_char;
 146         if s.is_null() {
 147             None
 148         } else {
 149             Some(OsStringExt::from_vec(CStr::from_ptr(s).to_bytes().to_vec()))
 150         }
 151     }
 152 }
 153
 154 pub fn setenv(k: &OsStr, v: &OsStr) -> io::Result<()> {
 155     let k = CString::new(k.as_bytes())?;
 156     let v = CString::new(v.as_bytes())?;
 157
 158     unsafe {
 159         let _guard = ENV_LOCK.write();
 160         cvt_env(libc::setenv(k.as_ptr(), v.as_ptr(), 1)).map(drop)
 161     }
 162 }
 163
 164 pub fn unsetenv(n: &OsStr) -> io::Result<()> {
 165     let nbuf = CString::new(n.as_bytes())?;
 166
 167     unsafe {
 168         let _guard = ENV_LOCK.write();
 169         cvt_env(libc::unsetenv(nbuf.as_ptr())).map(drop)
 170     }
 171 }
 172
 173 /// In kmclib, `setenv` and `unsetenv` don't always set `errno`, so this
 174 /// function just returns a generic error.
 175 fn cvt_env(t: c_int) -> io::Result<c_int> {
 176     if t == -1 { Err(io::const_io_error!(io::ErrorKind::Uncategorized, "failure")) } else { Ok(t) }
 177 }
 178
 179 pub fn temp_dir() -> PathBuf {
 180     panic!("no standard temporary directory on this platform")
 181 }
 182
 183 pub fn home_dir() -> Option<PathBuf> {
 184     None
 185 }
 186
 187 pub fn exit(_code: i32) -> ! {
 188     let tid = itron::task::try_current_task_id().unwrap_or(0);
 189     loop {
 190         abi::breakpoint_program_exited(tid as usize);
 191     }
 192 }
 193
 194 pub fn getpid() -> u32 {
 195     panic!("no pids on this platform")
 196 }