redox/kernel/syscall/fs.rs
2016-09-23 17:54:39 -06:00

248 lines
7.4 KiB
Rust

//! Filesystem syscalls
use context;
use scheme;
use syscall::data::Stat;
use syscall::error::*;
/// Change the current working directory
pub fn chdir(path: &[u8]) -> Result<usize> {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let canonical = context.canonicalize(path);
*context.cwd.lock() = canonical;
Ok(0)
}
/// Get the current working directory
pub fn getcwd(buf: &mut [u8]) -> Result<usize> {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let cwd = context.cwd.lock();
let mut i = 0;
while i < buf.len() && i < cwd.len() {
buf[i] = cwd[i];
i += 1;
}
Ok(i)
}
/// Open syscall
pub fn open(path: &[u8], flags: usize) -> Result<usize> {
let path_canon = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
context.canonicalize(path)
};
let mut parts = path_canon.splitn(2, |&b| b == b':');
let namespace_opt = parts.next();
let reference_opt = parts.next();
let (scheme_id, file_id) = {
let namespace = namespace_opt.ok_or(Error::new(ENOENT))?;
let (scheme_id, scheme) = {
let schemes = scheme::schemes();
let (scheme_id, scheme) = schemes.get_name(namespace).ok_or(Error::new(ENOENT))?;
(scheme_id, scheme.clone())
};
let file_id = scheme.open(reference_opt.unwrap_or(b""), flags)?;
(scheme_id, file_id)
};
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
context.add_file(::context::file::File {
scheme: scheme_id,
number: file_id
}).ok_or(Error::new(EMFILE))
}
/// Close syscall
pub fn close(fd: usize) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.remove_file(fd).ok_or(Error::new(EBADF))?;
file
};
context::event::unregister(fd, file.scheme, file.number);
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.close(file.number)
}
/// Duplicate file descriptor
pub fn dup(fd: usize) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.dup(file.number)
}
/// Register events for file
pub fn fevent(fd: usize, flags: usize) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.fevent(file.number, flags)?;
context::event::register(fd, file.scheme, file.number);
Ok(0)
}
/// Get the canonical path of the file
pub fn fpath(fd: usize, buf: &mut [u8]) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.fpath(file.number, buf)
}
/// Get information about the file
pub fn fstat(fd: usize, stat: &mut Stat) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.fstat(file.number, stat)
}
/// Sync the file descriptor
pub fn fsync(fd: usize) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.fsync(file.number)
}
/// Truncate the file descriptor
pub fn ftruncate(fd: usize, len: usize) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.ftruncate(file.number, len)
}
/// Seek to an offset
pub fn lseek(fd: usize, pos: usize, whence: usize) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.seek(file.number, pos, whence)
}
/// Read syscall
pub fn read(fd: usize, buf: &mut [u8]) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.read(file.number, buf)
}
/// Write syscall
pub fn write(fd: usize, buf: &[u8]) -> Result<usize> {
let file = {
let contexts = context::contexts();
let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
let context = context_lock.read();
let file = context.get_file(fd).ok_or(Error::new(EBADF))?;
file
};
let scheme = {
let schemes = scheme::schemes();
let scheme = schemes.get(file.scheme).ok_or(Error::new(EBADF))?;
scheme.clone()
};
scheme.write(file.number, buf)
}