Add more from the std

crates/std/src/sys/fs/common.rs

@@ -0,0 +1,81 @@
+#![allow(dead_code)] // not used on all platforms
+
+use crate::io::{self, Error, ErrorKind};
+use crate::path::{Path, PathBuf};
+use crate::sys::fs::{File, OpenOptions};
+use crate::sys::helpers::ignore_notfound;
+use crate::{fmt, fs};
+
+pub(crate) const NOT_FILE_ERROR: Error = io::const_error!(
+    ErrorKind::InvalidInput,
+    "the source path is neither a regular file nor a symlink to a regular file",
+);
+
+pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
+    let mut reader = fs::File::open(from)?;
+    let metadata = reader.metadata()?;
+
+    if !metadata.is_file() {
+        return Err(NOT_FILE_ERROR);
+    }
+
+    let mut writer = fs::File::create(to)?;
+    let perm = metadata.permissions();
+
+    let ret = io::copy(&mut reader, &mut writer)?;
+    writer.set_permissions(perm)?;
+    Ok(ret)
+}
+
+pub fn remove_dir_all(path: &Path) -> io::Result<()> {
+    let filetype = fs::symlink_metadata(path)?.file_type();
+    if filetype.is_symlink() { fs::remove_file(path) } else { remove_dir_all_recursive(path) }
+}
+
+fn remove_dir_all_recursive(path: &Path) -> io::Result<()> {
+    for child in fs::read_dir(path)? {
+        let result: io::Result<()> = try {
+            let child = child?;
+            if child.file_type()?.is_dir() {
+                remove_dir_all_recursive(&child.path())?;
+            } else {
+                fs::remove_file(&child.path())?;
+            }
+        };
+        // ignore internal NotFound errors to prevent race conditions
+        if let Err(err) = &result
+            && err.kind() != io::ErrorKind::NotFound
+        {
+            return result;
+        }
+    }
+    ignore_notfound(fs::remove_dir(path))
+}
+
+pub fn exists(path: &Path) -> io::Result<bool> {
+    match fs::metadata(path) {
+        Ok(_) => Ok(true),
+        Err(error) if error.kind() == io::ErrorKind::NotFound => Ok(false),
+        Err(error) => Err(error),
+    }
+}
+
+pub struct Dir {
+    path: PathBuf,
+}
+
+impl Dir {
+    pub fn open(path: &Path, _opts: &OpenOptions) -> io::Result<Self> {
+        path.canonicalize().map(|path| Self { path })
+    }
+
+    pub fn open_file(&self, path: &Path, opts: &OpenOptions) -> io::Result<File> {
+        File::open(&self.path.join(path), &opts)
+    }
+}
+
+impl fmt::Debug for Dir {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("Dir").field("path", &self.path).finish()
+    }
+}