Implement fd_filestat_get for all platforms

CraneStation · Jul 24, 2019 · 6610d03 · 6610d03
1 parent 86ae6e3
commit 6610d03
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Showing 5 changed files with 163 additions and 12 deletions.
diff --git a/build.rs b/build.rs
@@ -136,6 +136,7 @@ cfg_if::cfg_if! {
                     "file_pread_pwrite" => false,
                     "renumber" => false,
                     "file_seek_tell" => false,
+                    "file_allocate" => false,
                     _ => true,
                 }
             } else {

diff --git a/src/hostcalls_impl/fs.rs b/src/hostcalls_impl/fs.rs
@@ -4,7 +4,7 @@ use crate::fdentry::{Descriptor, FdEntry};
 use crate::memory::*;
 use crate::sys::{errno_from_host, host_impl, hostcalls_impl};
 use crate::{host, wasm32, Result};
-use log::trace;
+use log::{debug, trace};
 use std::io::{self, Read, Seek, SeekFrom, Write};
 
 pub(crate) fn fd_close(wasi_ctx: &mut WasiCtx, fd: wasm32::__wasi_fd_t) -> Result<()> {
@@ -730,13 +730,46 @@ pub(crate) fn fd_filestat_get(
         .get_fd_entry(fd, 0, 0)
         .and_then(|fe| fe.fd_object.descriptor.as_file())?;
 
-    let host_filestat = hostcalls_impl::fd_filestat_get(fd)?;
+    let host_filestat = fd_filestat_get_impl(fd).map_err(|e| {
+        debug!("fd_filestat_get: error: {}", e);
+        e.raw_os_error().map_or(host::__WASI_EIO, errno_from_host)
+    })?;
 
     trace!("     | *filestat_ptr={:?}", host_filestat);
 
     enc_filestat_byref(memory, filestat_ptr, host_filestat)
 }
 
+fn fd_filestat_get_impl(file: &std::fs::File) -> io::Result<host::__wasi_filestat_t> {
+    use std::convert::TryInto;
+    use std::time::{SystemTime, UNIX_EPOCH};
+    fn timestamp(st: SystemTime) -> io::Result<u64> {
+        st.duration_since(UNIX_EPOCH)
+            .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?
+            .as_nanos()
+            .try_into()
+            .map_err(|e: std::num::TryFromIntError| {
+                io::Error::new(io::ErrorKind::Other, e.to_string())
+            })
+    }
+    let metadata = file.metadata()?;
+    // On Windows all the information needed is either in libstd or provided by
+    // GetFileInformationByHandle winapi call. All of it is much easier to implement
+    // in libstd
+    Ok(host::__wasi_filestat_t {
+        st_dev: hostcalls_impl::device_id(file)?,
+        st_ino: hostcalls_impl::file_serial_no(file)?,
+        st_nlink: hostcalls_impl::num_hardlinks(file)?
+            .try_into()
+            .expect("overflow"),
+        st_size: metadata.len(),
+        st_atim: metadata.accessed().and_then(timestamp)?,
+        st_ctim: hostcalls_impl::change_time(file)?,
+        st_mtim: metadata.modified().and_then(timestamp)?,
+        st_filetype: hostcalls_impl::filetype(file)?,
+    })
+}
+
 pub(crate) fn fd_filestat_set_times(
     wasi_ctx: &WasiCtx,
     fd: wasm32::__wasi_fd_t,

diff --git a/src/sys/unix/hostcalls_impl/fs.rs b/src/sys/unix/hostcalls_impl/fs.rs
@@ -12,6 +12,7 @@ use std::ffi::CString;
 use std::fs::File;
 use std::os::unix::fs::FileExt;
 use std::os::unix::prelude::{AsRawFd, FromRawFd};
+use std::io;
 
 pub(crate) fn fd_pread(
     file: &File,
@@ -356,11 +357,49 @@ pub(crate) fn path_rename(
     }
 }
 
-pub(crate) fn fd_filestat_get(fd: &File) -> Result<host::__wasi_filestat_t> {
-    use nix::sys::stat::fstat;
-    let filestat =
-        fstat(fd.as_raw_fd()).map_err(|err| host_impl::errno_from_nix(err.as_errno().unwrap()))?;
-    host_impl::filestat_from_nix(filestat)
+pub(crate) fn num_hardlinks(file: &File) -> io::Result<u64> {
+    use std::os::unix::fs::MetadataExt;
+    Ok(file.metadata()?.nlink())
+}
+
+pub(crate) fn device_id(file: &File) -> io::Result<u64> {
+    use std::os::unix::fs::MetadataExt;
+    Ok(file.metadata()?.dev())
+}
+
+pub(crate) fn file_serial_no(file: &File) -> io::Result<u64> {
+    use std::os::unix::fs::MetadataExt;
+    Ok(file.metadata()?.ino())
+}
+
+pub(crate) fn filetype(file: &File) -> io::Result<host::__wasi_filetype_t> {
+    use std::os::unix::fs::FileTypeExt;
+    let ftype = file.metadata()?.file_type();
+    let ret = if ftype.is_file() {
+        host::__WASI_FILETYPE_REGULAR_FILE
+    } else if ftype.is_dir() {
+        host::__WASI_FILETYPE_DIRECTORY
+    } else if ftype.is_symlink() {
+        host::__WASI_FILETYPE_SYMBOLIC_LINK
+    } else if ftype.is_char_device() {
+        host::__WASI_FILETYPE_CHARACTER_DEVICE
+    } else if ftype.is_block_device() {
+        host::__WASI_FILETYPE_BLOCK_DEVICE
+    } else if ftype.is_socket() || ftype.is_fifo() {
+        // TODO we should use getsockopt to find out if it's
+        // SOCKET_STREAM or SOCKET_DGRAM
+        host::__WASI_FILETYPE_SOCKET_STREAM
+    } else {
+        host::__WASI_FILETYPE_UNKNOWN
+    };
+
+    Ok(ret)
+}
+
+pub(crate) fn change_time(file: &File) -> io::Result<u64> {
+    use std::os::unix::fs::MetadataExt;
+    use std::convert::TryInto;
+    Ok(file.metadata()?.ctime().try_into().unwrap())
 }
 
 pub(crate) fn fd_filestat_set_times(

diff --git a/src/sys/windows/hostcalls_impl/fs.rs b/src/sys/windows/hostcalls_impl/fs.rs
@@ -173,8 +173,39 @@ pub(crate) fn path_rename(
     unimplemented!("path_rename")
 }
 
-pub(crate) fn fd_filestat_get(fd: &File) -> Result<host::__wasi_filestat_t> {
-    unimplemented!("fd_filestat_get")
+pub(crate) fn num_hardlinks(file: &File) -> io::Result<u64> {
+    Ok(winx::file::get_fileinfo(file)?.nNumberOfLinks.into())
+}
+
+pub(crate) fn device_id(file: &File) -> io::Result<u64> {
+    Ok(winx::file::get_fileinfo(file)?.dwVolumeSerialNumber.into())
+}
+
+pub(crate) fn file_serial_no(file: &File) -> io::Result<u64> {
+    let info = winx::file::get_fileinfo(file)?;
+    let high = info.nFileIndexHigh;
+    let low = info.nFileIndexLow;
+    let no = ((high as u64) << 32) | (low as u64);
+    Ok(no)
+}
+
+pub(crate) fn change_time(file: &File) -> io::Result<u64> {
+    winx::file::change_time(file)
+}
+
+pub(crate) fn filetype(file: &File) -> io::Result<host::__wasi_filetype_t> {
+    let ftype = file.metadata()?.file_type();
+    let ret = if ftype.is_file() {
+        host::__WASI_FILETYPE_REGULAR_FILE
+    } else if ftype.is_dir() {
+        host::__WASI_FILETYPE_DIRECTORY
+    } else if ftype.is_symlink() {
+        host::__WASI_FILETYPE_SYMBOLIC_LINK
+    } else {
+        host::__WASI_FILETYPE_UNKNOWN
+    };
+
+    Ok(ret)
 }
 
 pub(crate) fn fd_filestat_set_times(

diff --git a/winx/src/file.rs b/winx/src/file.rs
@@ -1,9 +1,11 @@
 #![allow(non_camel_case_types)]
 use crate::{winerror, Result};
-use std::ffi::{OsStr, OsString};
-use std::os::windows::prelude::{OsStrExt, OsStringExt, RawHandle};
+use std::ffi::{c_void, OsStr, OsString};
+use std::fs::File;
+use std::io;
+use std::os::windows::prelude::{AsRawHandle, OsStrExt, OsStringExt, RawHandle};
 use winapi::shared::minwindef::{self, DWORD};
-use winapi::um::{fileapi, fileapi::GetFileType, winbase, winnt};
+use winapi::um::{fileapi, fileapi::GetFileType, minwinbase, winbase, winnt};
 
 /// Maximum total path length for Unicode in Windows.
 /// [Maximum path length limitation]: https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file#maximum-path-length-limitation
@@ -457,3 +459,48 @@ pub fn openat<S: AsRef<OsStr>>(
         Ok(handle)
     }
 }
+
+fn cvt(i: winapi::shared::minwindef::BOOL) -> io::Result<()> {
+    if i == 0 {
+        Err(io::Error::last_os_error())
+    } else {
+        Ok(())
+    }
+}
+
+pub fn get_fileinfo(file: &File) -> io::Result<fileapi::BY_HANDLE_FILE_INFORMATION> {
+    use fileapi::{GetFileInformationByHandle, BY_HANDLE_FILE_INFORMATION};
+    use std::mem;
+
+    let handle = file.as_raw_handle();
+    let info = unsafe {
+        let mut info: BY_HANDLE_FILE_INFORMATION = mem::zeroed();
+        cvt(GetFileInformationByHandle(handle, &mut info))?;
+        info
+    };
+
+    Ok(info)
+}
+
+pub fn change_time(file: &File) -> io::Result<u64> {
+    use fileapi::FILE_BASIC_INFO;
+    use minwinbase::FileBasicInfo;
+    use std::convert::TryInto;
+    use std::mem;
+    use winbase::GetFileInformationByHandleEx;
+
+    let handle = file.as_raw_handle();
+    let tm = unsafe {
+        let mut info: FILE_BASIC_INFO = mem::zeroed();
+        let infosize = mem::size_of_val(&info);
+        cvt(GetFileInformationByHandleEx(
+            handle,
+            FileBasicInfo,
+            &mut info as *mut FILE_BASIC_INFO as *mut c_void,
+            infosize as u32,
+        ))?;
+        *info.ChangeTime.QuadPart()
+    };
+
+    Ok(tm.try_into().unwrap())
+}