core: route view_image through a sandbox-backed fs helper

codex-rs/fs-ops/src/error.rs

@@ -0,0 +1,70 @@
+use serde::Deserialize;
+use serde::Serialize;
+use std::io::ErrorKind;
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum FsErrorKind {
+    NotFound,
+    PermissionDenied,
+    IsADirectory,
+    InvalidData,
+    Other,
+}
+
+impl From<ErrorKind> for FsErrorKind {
+    fn from(value: ErrorKind) -> Self {
+        match value {
+            ErrorKind::NotFound => Self::NotFound,
+            ErrorKind::PermissionDenied => Self::PermissionDenied,
+            ErrorKind::IsADirectory => Self::IsADirectory,
+            ErrorKind::InvalidData => Self::InvalidData,
+            _ => Self::Other,
+        }
+    }
+}
+
+impl FsErrorKind {
+    pub fn to_io_error_kind(&self) -> ErrorKind {
+        match self {
+            Self::NotFound => ErrorKind::NotFound,
+            Self::PermissionDenied => ErrorKind::PermissionDenied,
+            Self::IsADirectory => ErrorKind::IsADirectory,
+            Self::InvalidData => ErrorKind::InvalidData,
+            Self::Other => ErrorKind::Other,
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct FsError {
+    pub kind: FsErrorKind,
+    pub message: String,
+    pub raw_os_error: Option<i32>,
+}
+
+impl std::fmt::Display for FsError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str(&self.message)
+    }
+}
+
+impl FsError {
+    pub fn to_io_error(&self) -> std::io::Error {
+        if let Some(raw_os_error) = self.raw_os_error {
+            std::io::Error::from_raw_os_error(raw_os_error)
+        } else {
+            std::io::Error::new(self.kind.to_io_error_kind(), self.message.clone())
+        }
+    }
+}
+
+impl From<std::io::Error> for FsError {
+    fn from(error: std::io::Error) -> Self {
+        Self {
+            kind: error.kind().into(),
+            message: error.to_string(),
+            raw_os_error: error.raw_os_error(),
+        }
+    }
+}